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SpaceX Vehicles and Missions => SpaceX Reusability => Topic started by: dcporter on 06/01/2015 08:41 pm

Title: Fairing reuse
Post by: dcporter on 06/01/2015 08:41 pm
An interesting hint at fairing reusability in a tweetback from Elon:

https://twitter.com/elonmusk/status/605460768516014080
Title: Re: Fairing reuse
Post by: meekGee on 06/01/2015 08:56 pm
I didn't believe this when the first hints showed up, but I guess it's for real...

Well, if anyone can pull this off right now, it's SpaceX.
Title: Re: Fairing reuse
Post by: ClayJar on 06/01/2015 09:17 pm
Apparently three of them found the fairing piece:

Kevin (twitter (https://twitter.com/kpe)) posted a full set of high-res original images on his dropbox (https://www.dropbox.com/sh/vzvobzwhwdz6mdd/AADl7VIEFMrPaGMS2r3rR-XAa).
Grier (twitter (https://twitter.com/grierallen)) said they were sending GoPro/card back to SpaceX.
Nate (twitter (https://twitter.com/natedapore)) posted another high-res shot on ow.ly (http://ow.ly/i/b3Bcl/original).

(Should someone attach the photos for posterity?)
Title: Re: Fairing reuse
Post by: Comga on 06/01/2015 09:30 pm
Can anyone explain the details seen in the images?
That's a GoPro camera in an aerospace grade housing?
Whatt about the access port, the hose, those wavy metal straps, the ball tipped long arm, and the short rounded arm?
I am not sure this is really OT for reuseable farings.  This one is definitely not reuseable, although the camera might be.
Title: Re: Fairing reuse
Post by: Elmar Moelzer on 06/01/2015 09:35 pm
I am not sure this is really OT for reuseable farings.  This one is definitely not reuseable, although the camera might be.
IMHO it is on topic, because Musk wants to use the information gathered from it for their future reusable fairings.
Title: Re: Fairing reuse
Post by: ClayJar on 06/01/2015 09:53 pm
Can anyone explain the details seen in the images?
That's a GoPro camera in an aerospace grade housing?
Whatt about the access port, the hose, those wavy metal straps, the ball tipped long arm, and the short rounded arm?
I am not sure this is really OT for reuseable farings.  This one is definitely not reuseable, although the camera might be.
The big hoses must be for environmental control (air conditioning the insides of the fairing before launch), as I can't think of anything else that would make sense.  The wavy metal straps are brackets for the large hoses, which were attached with zip ties.  (The remaining longer hose piece is still attached to some of them with the same zip ties that are present in some of the now empty brackets.)

The long arm with a ball joint at one end has a hinge at the remaining attachment, and the short round heavy-duty eye appears to contain a bearing.  Obviously related to moving parts (for fairing sep?).

And it's two GoPro camera/data logger housings, actually.  One is clearly visible, and the second is by the two big hoses near the side (the ball-tipped arm nearly hits it).  We've only seen occasional glimpses inside the fairing during launch video, but they apparently are kitted out for more than we see (which is, of course, a gross understatement).  I can only imagine that if the GoPro cameras continued rolling after fairing sep, having them back with full-resolution imagery and so on could provide some quite handy information.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 06/01/2015 10:09 pm
(Should someone attach the photos for posterity?)

I inadvertently created a duplicate thread. Here are the initial photo's I uploaded.

Still can't get my head around that it's worth the effort to re-use fairings!
Title: Re: Fairing reuse
Post by: Arcas on 06/01/2015 10:28 pm
Why not just attach the fairings to hinges, and snap them shut after releasing payload instead of blowing them off.
Title: Re: Fairing reuse
Post by: DMeader on 06/01/2015 10:33 pm
Why not just attach the fairings to hinges, and snap them shut after releasing payload instead of blowing them off.

They separate to reduce weight. At that point in the ascent they are no longer needed to protect the payload. However, the vehicle is still under power, significantly before the payload is released.
Title: Re: Fairing reuse
Post by: meekGee on 06/01/2015 10:37 pm
Still can't get my head around that it's worth the effort to re-use fairings!

This is circumstantial evidence that cost/launch is headed way down.

I know they're expending the second stage which is more expensive than a fairing, but still somehow they decided this is important enough to bother.  odd.
Title: Re: Fairing reuse
Post by: Robotbeat on 06/01/2015 11:34 pm
Why not just attach the fairings to hinges, and snap them shut after releasing payload instead of blowing them off.
Because fairings are attached to the upper stage and so you'd have to bring it all away up to orbit. You could attach the fairing to the first stage like an atlas V (an idea I like and toyed with once when designing an RLV) but then the fairing would have to be at least twice as big.
Title: Re: Fairing reuse
Post by: sojourner on 06/02/2015 01:29 am
Maybe the "reuse" part of the tweet was just Elon being Flippant?
Title: Re: Fairing reuse
Post by: Jim on 06/02/2015 01:47 am

1.  What about the access port,
2.  the hose, those wavy metal straps,
3.  the ball tipped long arm,
4.   and the short rounded arm?


1.  For spacecraft access
2.  AC ducts
3.  Push rod for fairing sep
4.  fairing sep system
Title: Re: Fairing reuse
Post by: Elmar Moelzer on 06/02/2015 01:48 am
I have always wondered why they wait a full minute after the separation of the second stage for the separation of the fairing. Is there anything preventing them from doing that event earlier? If not, how early could it theoretically happen? Given the heavy SpaceX fairing, an earlier fairing separation could IMHO mean a bit of extra performance (and for reuse getting it down closer to the launch site might be beneficial too).
Title: Re: Fairing reuse
Post by: Jim on 06/02/2015 01:53 am
I have always wondered why they wait a full minute after the separation of the second stage for the separation of the fairing. Is there anything preventing them from doing that event earlier? If not, how early could it theoretically happen? Given the heavy SpaceX fairing, an earlier fairing separation could IMHO mean a bit of extra performance (and for reuse getting it down closer to the launch site might be beneficial too).

Yes there is something.  There is a requirement for the free molecular heating to be below a certain level. The level is determined by spacecraft requirements.
Title: Re: Fairing reuse
Post by: bstrong on 06/02/2015 03:29 am
Still can't get my head around that it's worth the effort to re-use fairings!

This is circumstantial evidence that cost/launch is headed way down.

I know they're expending the second stage which is more expensive than a fairing, but still somehow they decided this is important enough to bother.  odd.

I wonder if they've come to the conclusion that maintaining hazard zones like they do today is going to prevent them from achieving super-high launch rates

Assuming they can someday convince the FAA/USAF that the risk of dropping first stages on unsuspecting boaters is comparable to the risk of planes falling out of the sky on them, uncontrolled fairing descent could be the only reason for keeping the hazard zones around.
Title: Re: Fairing reuse
Post by: Elmar Moelzer on 06/02/2015 04:23 am
Yes there is something.  There is a requirement for the free molecular heating to be below a certain level. The level is determined by spacecraft requirements.
You mean heating from the air (as minimal as it may be at that altitude)?
Is there an ballpark altitude for that? Just curious.
Title: Re: Fairing reuse
Post by: Galactic Penguin SST on 06/02/2015 05:16 am
Yes there is something.  There is a requirement for the free molecular heating to be below a certain level. The level is determined by spacecraft requirements.
You mean heating from the air (as minimal as it may be at that altitude)?
Is there an ballpark altitude for that? Just curious.

More than 100 km high in most cases - usually closer to 110-130 km.
Title: Re: Fairing reuse
Post by: Jim on 06/02/2015 10:54 am

You mean heating from the air (as minimal as it may be at that altitude)?
Is there an ballpark altitude for that? Just curious.

It is a function of vehicle velocity also well as air density.  So, there isn't a specific altitude.
Title: Re: Fairing reuse
Post by: MattMason on 06/02/2015 12:42 pm
Why not just attach the fairings to hinges, and snap them shut after releasing payload instead of blowing them off.

Looks like, historically, full separation of fairings is the safer plan, too. Apollo 7's S-IVB adapter panels simply opened like flower petals. But they opened asymmetrically and concerned mission planners that future LM extractions or the CSM would be jeopardized. So fairing jettison was the way to go to avoid collisions or obstructions.

I don't think a recloseable fairing system would work. First, how would it safely move off the vehicle? That would require it to open up like a clamshell to provide payload clearance and then be propelled upward like a launch escape system tower, and then commanded to close again.

Even if the fairing was jettisoned whole, like the pulling the cover to the tip of a pen, it would need to be larger in diameter to add a little extra space to avoid brushing the payload as it exits. In either case, the fairing is heavier with the jettison jets and separation must be perfect or the payload or LV is in jeopardy.

None of my fanciful speculations will stop a company from figuring out an idea to make that work, however.
Title: Re: Fairing reuse
Post by: deruch on 06/02/2015 01:47 pm
Full res posted to dropbox:  https://www.dropbox.com/sh/vzvobzwhwdz6mdd/AADl7VIEFMrPaGMS2r3rR-XAa

Images rehosted at:
https://imgur.com/a/SyfRN

Galleries from previous finds of SpaceX fairing pieces-
Found in Hawaii:  https://imgur.com/a/g06A2

Found in Cape Hatteras, NC: https://imgur.com/a/0bo6s


edit: updated original gallery to include the full set of pictures from the dropbox posting and added the previous galleries for comparison.
Title: Re: Fairing reuse
Post by: Comga on 06/02/2015 02:05 pm

1.  What about the access port,
2.  the hose, those wavy metal straps,
3.  the ball tipped long arm,
4.   and the short rounded arm?

1.  For spacecraft access
2.  AC ducts
3.  Push rod for fairing sep
4.  fairing sep system

Thanks. Can you be more descriptive or point to a reference?
The "push rod" is clear
Is the "fairing step system" something that was held to a matching piece on the other half with an explosive bolt?
Do AC ducts attach to payloads or just direct the purge flow at specific points?  My assumption was that clean dry gas just flowed into the fairing and out some small port.
Any description of how the access port is opened or held closed in those images?
Title: Re: Fairing reuse
Post by: Jim on 06/02/2015 02:15 pm

1.  Is the "fairing step system" something that was held to a matching piece on the other half with an explosive bolt?
2.  Do AC ducts attach to payloads or just direct the purge flow at specific points?  My assumption was that clean dry gas just flowed into the fairing and out some small port.
3.  Any description of how the access port is opened or held closed in those images?


1.  Yes, but the release mechanism is not explosive.  (Spacex has an aversion to them)
2.  The ducts lead to the top of the fairing where the air "showers" over the payload.
3.  Just standard fasteners (screws)
Title: Re: Fairing reuse
Post by: Donosauro on 06/02/2015 04:05 pm
I don't know how conventional China Great Wall's payload fairings are, but this chapter of one of their user manuals shows both the input port for conditioned air and a number of exhaust ports:

http://www.cgwic.com/LaunchServices/Download/manual/Chapter%204%20Payload%20Fairing.pdf
Title: Re: Fairing reuse
Post by: Kabloona on 06/02/2015 04:35 pm
Info from the GoPro camera/data logger housing photos:

For the top level assembly:

P/N 00195412-501 Rev A
"Assy, GoPro Housing, Data Logger, Fair" (ie fairing)
Serial numbers 1 and 15 on the two housings shown in the photos

Quick Response code on the label for inventory control/build logs: SPXGUY4

For the cover plate:

P/N 00195412-002 Rev A
PO 387118 (probably a purchase order number, indicating outsourced, not made in-house)

Assembled with NAS6703 bolts, standard aerospace grade made of A286 CRES.

Nothing surprising, but a few interesting tidbits, like the use of GoPro cameras.
Title: Re: Fairing reuse
Post by: starsilk on 06/02/2015 04:38 pm
Still can't get my head around that it's worth the effort to re-use fairings!

This is circumstantial evidence that cost/launch is headed way down.

I know they're expending the second stage which is more expensive than a fairing, but still somehow they decided this is important enough to bother.  odd.

we need to think of the long game. it may not be terribly economic to reuse them on the F9 (or perhaps even a loss), but they are learning how to do it for the MCT when the fairing is going to be MUCH bigger and more valuable.

MCT is presumably going to be big enough and expensive enough that it simply has to be fully reused, otherwise it's not economic - except for a rare government launch perhaps where they can afford to throw away hundreds of millions of dollars of hardware.
Title: Re: Fairing reuse
Post by: speedevil on 06/02/2015 07:59 pm
<snip of why fairing is jetisoned after staging, not at>
Yes there is something.  There is a requirement for the free molecular heating to be below a certain level. The level is determined by spacecraft requirements.

In principle, a very, very light structure - perhaps even inflated could be added inside for a shield in the minute or so afterwards.
A quick calculation indicates Q at this point is well under 1Pa.
(I uses ~M6 and 100km as ballpark staging point).

That doesn't of course answer the awkward point of how you'd get the fairing down to the first stage, and attach it. (swelling dramatically the fairing doesn't seem sane)

If there was an easy way to join the fairing halves again, they'd be a lot more structurally robust, and in principle would have quite a low terminal velocity and weight allowing catch by copter.
Title: Re: Fairing reuse
Post by: Elmar Moelzer on 06/02/2015 08:30 pm

You mean heating from the air (as minimal as it may be at that altitude)?
Is there an ballpark altitude for that? Just curious.

It is a function of vehicle velocity also well as air density.  So, there isn't a specific altitude.
Thanks, makes sense! So how does that fit in with the suggestion by some to make the fairing part of the first stage (I think someone said that Atlas does that) which would mean fairing separation about a minute earlier?
Does Atlas do the staging later in the flight envelope?
Title: Re: Fairing reuse
Post by: RanulfC on 06/02/2015 09:37 pm
Check me on this,

It looks like the thing broke up on impact with the ocean so it would seem "reuse" would be on the order of making that event survivable. That however does nothing for the range restrictions issues.

Probably a "bad" idea but what about having the fairing separate along one side and then eject side-ways so that it could close up for reentry?

(And what's this about a "fairing" for the MCT?)

Randy
Title: Re: Fairing reuse
Post by: dcporter on 06/03/2015 05:23 am
Check me on this,

It looks like the thing broke up on impact with the ocean so it would seem "reuse" would be on the order of making that event survivable. That however does nothing for the range restrictions issues.

Probably a "bad" idea but what about having the fairing separate along one side and then eject side-ways so that it could close up for reentry?

(And what's this about a "fairing" for the MCT?)

Randy

If the problem is landing rather than falling, how would clamming back up help? I'd think that would reduce drag, increasing the speed left at impact.
Title: Re: Fairing reuse
Post by: Jim on 06/03/2015 01:44 pm

Thanks, makes sense! So how does that fit in with the suggestion by some to make the fairing part of the first stage (I think someone said that Atlas does that) which would mean fairing separation about a minute earlier?
Does Atlas do the staging later in the flight envelope?

For the 5m, the fairing comes off before 2nd stage sep.
For the 4m, it comes off after 2nd stage start.
Most fairings on other vehicles come off after 2nd stage start.
Title: Re: Fairing reuse
Post by: Jim on 06/03/2015 01:45 pm

In principle, a very, very light structure - perhaps even inflated could be added inside for a shield in the minute or so afterwards.


Why?  That is the main purpose of the fairing, so why duplicate it and make the system more complex?
Title: Re: Fairing reuse
Post by: Elmar Moelzer on 06/03/2015 02:50 pm
For the 5m, the fairing comes off before 2nd stage sep.
For the 4m, it comes off after 2nd stage start.
Most fairings on other vehicles come off after 2nd stage start.
Thanks, Jim!
So what speaks against an F9 fairing that always comes off at or shortly before second stage separation? It is obviously possible to do it, since Atlas is doing it with the 5m fairing.
Title: Re: Fairing reuse
Post by: RanulfC on 06/03/2015 03:08 pm
If the problem is landing rather than falling, how would clamming back up help? I'd think that would reduce drag, increasing the speed left at impact.

Drag should be about the same with both halves being rejoined you have only a single "piece" rather than two to track/control to landing. The halves should also be more supporting together than when separated.
I'm just throwing an idea out but frankly I don't see "fairing-reuse" as being serious.

Randy
Title: Re: Fairing reuse
Post by: Jim on 06/03/2015 04:30 pm

So what speaks against an F9 fairing that always comes off at or shortly before second stage separation? It is obviously possible to do it, since Atlas is doing it with the 5m fairing.

Spacecraft requirements for the environment. 

There is a "blackout" period around stage separation that fairing separation is usually not performed.  The vehicle goes into attitude hold in preparation for booster shutdown.  After shutdown, the vehicle is not accelerating and so fairing sep can't really be done.  There are transients and attitude excursions associated with second stage coast and ignition, so fairing sep is set off few seconds (5 or so after the engine is steady state)

Atlas V first stage burn out is around 240 seconds. 
Fairing come off at 270 seconds for 4 meter (during 2nd stage burn)
Fairing come off at 200 seconds for 5 meter (during 1st stage burn)

Velocity has a role in determining environments, a 5m mission is going to be slower for a given movement is the timeline vs a 4m.

F9 first stage burn out is around 150 seconds.
Falcon 9 fairing comes off at 210 seconds

So, the fairing on F9 isn't going to come off earlier. 
Title: Re: Fairing reuse
Post by: guckyfan on 06/03/2015 04:34 pm
So what speaks against an F9 fairing that always comes off at or shortly before second stage separation? It is obviously possible to do it, since Atlas is doing it with the 5m fairing.

Falcon 9R stages very early. So the payload still needs some protection, I would assume.
Title: Re: Fairing reuse
Post by: meekGee on 06/03/2015 09:40 pm
So what speaks against an F9 fairing that always comes off at or shortly before second stage separation? It is obviously possible to do it, since Atlas is doing it with the 5m fairing.

Falcon 9R stages very early. So the payload still needs some protection, I would assume.

I think F9R also flies a more lofted trajectory, which should in principle help to drop the fairing earlier.
Title: Re: Fairing reuse
Post by: douglas100 on 06/03/2015 10:01 pm
I think a re-usable fairing only makes economic and technical sense as part of a re-usable upper stage, maybe like  the Kistler K-1. Bottom line, a re-usable fairing is a non-starter for current vehicles. The extra complexity for little economic return makes it not worth it IMHO.

Since a fairing carried to orbit is going to cause a large payload hit, it only makes sense for a much larger re-usable vehicle.

Title: Re: Fairing reuse
Post by: nadreck on 06/03/2015 10:04 pm
I think a re-usable fairing only makes economic and technical sense as part of a re-usable upper stage, maybe like  the Kistler K-1. Bottom line, a re-usable fairing is a non-starter for current vehicles. The extra complexity for little economic return makes it not worth it IMHO.

Since a fairing carried to orbit is going to cause a large payload hit, it only makes sense for a much larger re-usable vehicle.

And if the initial investment in each fairing is $1M and the cost to recover and recommission is $500,000 you wouldn't do it?
Title: Re: Fairing reuse
Post by: douglas100 on 06/03/2015 10:11 pm
I think a re-usable fairing only makes economic and technical sense as part of a re-usable upper stage, maybe like  the Kistler K-1. Bottom line, a re-usable fairing is a non-starter for current vehicles. The extra complexity for little economic return makes it not worth it IMHO.

Since a fairing carried to orbit is going to cause a large payload hit, it only makes sense for a much larger re-usable vehicle.

And if the initial investment in each fairing is $1M and the cost to recover and recommission is $500,000 you wouldn't do it?

Not unless you could demonstrate these numbers are real.
Title: Re: Fairing reuse
Post by: nadreck on 06/03/2015 10:17 pm
I think a re-usable fairing only makes economic and technical sense as part of a re-usable upper stage, maybe like  the Kistler K-1. Bottom line, a re-usable fairing is a non-starter for current vehicles. The extra complexity for little economic return makes it not worth it IMHO.

Since a fairing carried to orbit is going to cause a large payload hit, it only makes sense for a much larger re-usable vehicle.

And if the initial investment in each fairing is $1M and the cost to recover and recommission is $500,000 you wouldn't do it?

Not unless you could demonstrate these numbers are real.

I obviously was not succinct. Please perform the thought experiment: imagine that each fairing costs $1M to produce and the amortized cost of the equipment to make them reusable, the use of the craft to do the recovery, and the recommissioning expense adds up to $500,000.  Now having considered that, would you go ahead with the project to recover them?
Title: Re: Fairing reuse
Post by: deruch on 06/04/2015 02:57 am
The issue for SpaceX is their ability to make enough fairings.  They are currently ramping up their flight rate very quickly.  Even with a decent number of future launches being Dragons (i.e. no fairing), they are still going to need a whole lot more of them per year in the near future.  What is their manufacturing capability?  How expandable is that capability?  What is the cost comparison between having to open additional production lines vs. investment to make them reusable?  etc. 
Title: Re: Fairing reuse
Post by: meekGee on 06/04/2015 04:19 am
The issue for SpaceX is their ability to make enough fairings.  They are currently ramping up their flight rate very quickly.  Even with a decent number of future launches being Dragons (i.e. no fairing), they are still going to need a whole lot more of them per year in the near future.  What is their manufacturing capability?  How expandable is that capability?  What is the cost comparison between having to open additional production lines vs. investment to make them reusable?  etc.

The constellation might require as much as one launch per week.

I'm surprised though that fairing manufacturing is not dwarfed by second stage manufacturing.  I guess it isn't...
Title: Re: Fairing reuse
Post by: douglas100 on 06/04/2015 08:16 am

I obviously was not succinct. Please perform the thought experiment: imagine that each fairing costs $1M to produce and the amortized cost of the equipment to make them reusable, the use of the craft to do the recovery, and the recommissioning expense adds up to $500,000.  Now having considered that, would you go ahead with the project to recover them?

All you're saying is, if it saves money, wouldn't you go ahead and do it? In my original post I gave the opinion that recovering the fairing from current vehicles (specifically F9)  wouldn't save money and therefore I wouldn't do it.

By all means argue the point, but please back it up with facts or a technical argument rather than pulling numbers out of the air and calling them a "thought experiment."
Title: Re: Fairing reuse
Post by: CJ on 06/04/2015 08:46 am
I think a re-usable fairing only makes economic and technical sense as part of a re-usable upper stage, maybe like  the Kistler K-1. Bottom line, a re-usable fairing is a non-starter for current vehicles. The extra complexity for little economic return makes it not worth it IMHO.

Since a fairing carried to orbit is going to cause a large payload hit, it only makes sense for a much larger re-usable vehicle.

My take; SpaceX wouldn't be working on fairing recovery for the F9 and FH unless they could see an economic reason to do so.

Going by what they've said, they have a limit on how many fairings they can produce per year. I assume that they could increase their capacity, but doing so would cost a significant amount of money. That $, plus the per unit cost, must be high enough to make reuse attractive to them. The fact that they are considering it makes it near certain that it's economically attractive - assuming it works like they think.   

If (and it's a big if) the fairing halves survive up until impact in a reusable state, my guess is that recovery isn;t all that hard, theoretically, nor would it be much of a mass penalty. For example, add a GPS beacon and a small drogue on a long line, and use a helicopter to grab it. Hrmmm... fly the helicopters off an ASDS?

 
Title: Re: Fairing reuse
Post by: Robotbeat on 06/04/2015 12:18 pm
If you're flying, say, 40 or 50 times per year, it may indeed make sense to reuse the fairing.
Title: Re: Fairing reuse
Post by: LouScheffer on 06/04/2015 02:06 pm

All you're saying is, if it saves money, wouldn't you go ahead and do it? In my original post I gave the opinion that recovering the fairing from current vehicles (specifically F9)  wouldn't save money and therefore I wouldn't do it.

By all means argue the point, but please back it up with facts or a technical argument rather than pulling numbers out of the air and calling them a "thought experiment."

Here's a rough guess I made when fairing recovery was only in L2, which I've fixed since I had the wrong launch rate for Ariane 5:

From "RUAG Space wins major Ariane 5 payload fairing contract " http://www.ruag.com/space/media/media-releases/news/ruag-space-wins-major-ariane-5-payload-fairing-contract/c1d44492a47610accba20f7849f17843/ , the contract is for $100M (one swiss franc is about a dollar), signed in 2014, and runs through 2019.  Assuming they did not wait until the last minute to sign this, I'm guessing through 2016 was in the prior contract.  Then this would be roughly 18 fairings (6 per year for 2017, 2018, 2019), or about $5-6M each.

SpaceX makes them in-house, so they might already have a cost advantage.  But if they can recover and refurbish a fairing for $1M, then they've got a $5M per flight advantage over Ariane and Atlas V  (which use the RUAG fairings).  When you are trying to drive the cost down to a few 10s of millions, that helps considerably.   To be competitive on cost, Atlas VI and Ariane VI will now need to be cheaper than SpaceX, not just equivalent.
Title: Re: Fairing reuse
Post by: nadreck on 06/04/2015 02:09 pm

I obviously was not succinct. Please perform the thought experiment: imagine that each fairing costs $1M to produce and the amortized cost of the equipment to make them reusable, the use of the craft to do the recovery, and the recommissioning expense adds up to $500,000.  Now having considered that, would you go ahead with the project to recover them?

All you're saying is, if it saves money, wouldn't you go ahead and do it? In my original post I gave the opinion that recovering the fairing from current vehicles (specifically F9)  wouldn't save money and therefore I wouldn't do it.

By all means argue the point, but please back it up with facts or a technical argument rather than pulling numbers out of the air and calling them a "thought experiment."

Actually the post I was responding to suggested it saved only a little money and was not worth it.  I work in an industry where it is worth effort of some participants to organize their schedule of activity of several different $5M capital projects just to save about $100,000 on each.  Other participants don't fine tune this way. Yet cutting the capital cost is worth it as long as it doesn't increase risk significantly.

Given that your opinion as most recently expressed is that it will cost more to recover a fairing than to manufacture a new one then my question was irrelevant.
Title: Re: Fairing reuse
Post by: JasonAW3 on 06/04/2015 02:23 pm
     I might be a bit off base here, but it occures to me that the Fairing reuse may not be just for launches from Earth.

     On Mars, fairings are dumped for each lander.  This is material that has cost quite a bit of money to launch to Mars.  As larger landers will likely require larger heat shields and fairings, recovery of these could be QUITE useful as building materials.  As heatshields have a curved surface, epoxying a number of them together to create a geodesic dome, would not be all that difficult and could provide fairly decent surface storage facilities after a few landings.  Any uppe fairings could also be made somewhat curved or simply used as is, if the fairing is large enough.
Title: Re: Fairing reuse
Post by: douglas100 on 06/04/2015 02:23 pm

....Given that your opinion as most recently expressed is that it will cost more to recover a fairing than to manufacture a new one then my question was irrelevant.

That's right, that was my opinion, but LouScheffer's numbers give me pause.
Title: Re: Fairing reuse
Post by: douglas100 on 06/04/2015 02:38 pm

....If (and it's a big if) the fairing halves survive up until impact in a reusable state, my guess is that recovery isn't all that hard, theoretically, nor would it be much of a mass penalty. For example, add a GPS beacon and a small drogue on a long line, and use a helicopter to grab it. Hrmmm... fly the helicopters off an ASDS?

You've put your finger on one difficulty in your first sentence (my bold). Another would be the uncontrolled flight of the fairing halves before recovery. Details and trades, as ever...

However, assuming the helicopters can get to them in time, then mid air recovery makes sense. Suggest the ULA approach and use parafoils rather than drogues to avoid a high vertical velocity before capture.
Title: Re: Fairing reuse
Post by: Comga on 06/04/2015 03:49 pm
(snip).
Hmmm... fly the helicopters off an ASDS?

This was mentioned before, and makes a lot of sense.  You don't want to send helicopters out to sea to hover, burning fuel during any hold.  Better to cruise out onboard a ship, and wait to fire up until terminal coundown.  After capture, instead of a long trip to shore with the giant sail-like fairing half, it gets deposited on the deck. 
Not obvious whether it would be better to land the helos on the barge or fly back unburdened.  Is there enough room on one of these barges to launch two helicopters, or to land two helicopters AND the fairing halves.

The main rotors on the CH-47D are listed (http://147thhillclimbers.org/hill_site/pdf_file/Chinook%20Legacy-January%202014.pdf) as ~98' in length and ~61' in width.
Is the 175' wide by ~250' long deck big enough for landing (dockside or at sea) and take-off, even without hanging fairing halves?
Title: Re: Fairing reuse
Post by: baldusi on 06/04/2015 04:17 pm
     I might be a bit off base here, but it occures to me that the Fairing reuse may not be just for launches from Earth.

     On Mars, fairings are dumped for each lander.  This is material that has cost quite a bit of money to launch to Mars.  As larger landers will likely require larger heat shields and fairings, recovery of these could be QUITE useful as building materials.  As heatshields have a curved surface, epoxying a number of them together to create a geodesic dome, would not be all that difficult and could provide fairly decent surface storage facilities after a few landings.  Any uppe fairings could also be made somewhat curved or simply used as is, if the fairing is large enough.
First, that's too far into the future. And second, it would sem that the MCT would land and launch as a whole to/from Mars. This is for Earth only, and if the L2 con ops are realized, it would only work on Earth.
Title: Re: Fairing reuse
Post by: The Amazing Catstronaut on 06/04/2015 04:52 pm

Is the 175' wide by ~250' long deck big enough for landing (dockside or at sea) and take-off, even without hanging fairing halves?

Sure should be. Helicopters can manage to land (and take back off) on very small floating pads on objects less stable than the ASDS.

Edit: I wonder if SpaceX will rent their skycranes or purchase them? I'd be heading for the latter.
Title: Re: Fairing reuse
Post by: RanulfC on 06/04/2015 07:15 pm

All you're saying is, if it saves money, wouldn't you go ahead and do it? In my original post I gave the opinion that recovering the fairing from current vehicles (specifically F9)  wouldn't save money and therefore I wouldn't do it.

By all means argue the point, but please back it up with facts or a technical argument rather than pulling numbers out of the air and calling them a "thought experiment."

Here's a rough guess I made when fairing recovery was only in L2, which I've fixed since I had the wrong launch rate for Ariane 5:

From "RUAG Space wins major Ariane 5 payload fairing contract " http://www.ruag.com/space/media/media-releases/news/ruag-space-wins-major-ariane-5-payload-fairing-contract/c1d44492a47610accba20f7849f17843/ , the contract is for $100M (one swiss franc is about a dollar), signed in 2014, and runs through 2019.  Assuming they did not wait until the last minute to sign this, I'm guessing through 2016 was in the prior contract.  Then this would be roughly 18 fairings (6 per year for 2017, 2018, 2019), or about $5-6M each.

SpaceX makes them in-house, so they might already have a cost advantage.  But if they can recover and refurbish a fairing for $1M, then they've got a $5M per flight advantage over Ariane and Atlas V  (which use the RUAG fairings).  When you are trying to drive the cost down to a few 10s of millions, that helps considerably.   To be competitive on cost, Atlas VI and Ariane VI will now need to be cheaper than SpaceX, not just equivalent.

Uhm, the cost savings isn't as clear as that because recovery and refurbishment doesn't factor in having to make them (apparently) more robust in the first place as well as adding a recovery system. The fairings are going to fall well away from the first stage recovery vehicles so that requires another set of recovery vehicles and personnel which adds costs. (Assuming that Elon wasn't being flippant in the first place :) )

The uncontrolled nature of the falling fairings also adds up costs as you have to make the assumption that you will need a helicopter for each fairing half. "Fixing" that issue means added mass and complexity which increases construction costs and impacts payload and reduces the case for reusability in the first place. And you have to include the possibility that one or both fairing halves on any flight will end up being outside your recovery area and you "lose" them anyway with added (due to stationing the recovery vehicles and crews) instead of saved costs.

I'd see saving's range starting out lower around @$4million initially at best from the given information.

With a high enough flight rate the numbers might point towards reusability but it wouldn't seem so at present.
(Second stage efficiency and reusability would to me seem a higher priority)

Randy
Title: Re: Fairing reuse
Post by: jimbowman on 06/05/2015 09:48 pm
 https://www.youtube.com/watch?v=4_sLTe6-7SE
Title: Re: Fairing reuse
Post by: ClayJar on 06/05/2015 10:10 pm
Beautiful footage.  I suppose this means they got the GoPro cameras and cards from the guys who found the piece in the Bahamas.

Too bad we didn't get the special Extended Edition that goes all the way down.  I wonder what we'll get to see when they actually start active fairing recovery tests. :)
Title: Re: Fairing reuse
Post by: meekGee on 06/05/2015 10:58 pm
Finally, footage worthy of the background music...  :)
Title: Re: Fairing reuse
Post by: matthewkantar on 06/05/2015 11:20 pm
Video is really breath taking. What are the objects that keep showing up? Sun obviously. Moon? Second stage firing? other fairing half? Planets? Stars?

Matthew
Title: Re: Fairing reuse
Post by: Lars-J on 06/06/2015 03:09 am
Video is really breath taking. What are the objects that keep showing up? Sun obviously. Moon? Second stage firing? other fairing half? Planets? Stars?

Matthew

Likely the second stage, and the other fairing half.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 06/06/2015 03:56 am
Yes, very cool video. It has it's own thread at http://forum.nasaspaceflight.com/index.php?action=profile;u=18754 (http://forum.nasaspaceflight.com/index.php?action=profile;u=18754).
Title: Re: Fairing reuse
Post by: Mariusuiram on 06/08/2015 08:09 am
Not getting into "economics" here with Marginal Costs, etc, but keep in mind that cost comparisons should account for variable & fixed production costs (cost to build a fairing), CAPEX to expand or add a new factory as they grow, operational expenses of reuse / refurbishment operation, and R&D investment in figuring this out (adding GoPros to existing fairings, staff time, possibly adding RCS or foils or something to existing fairings)

Lets say Ariane pays $5 million per fairing and SpaceX does it for $2 million in blended cost at their current max run rate in their factory.

While its easy to ask, does the cost to produce outweigh the refurbishment cost, there is a a better hurdle to view.

SpaceX likely has a good deal on their current factory space and from photos appears to use it all in their production efforts. Additional expansion opportunities may be limited or may require new development that will be more expensive.

So ignoring the operational costs for a moment. If SpaceX needs to expand its fairing production into a neighboring facility that could involve a $10-15 million CAPEX for space and equipment. And moreso that might be space that could go to Stage II production expansion or Dragon expansion etc. So there could be a higher opportunity cost there.

That may be the decision driver right there. Even if operational and refurbishment costs eat up savings, avoiding growing their fixed asset and production base may justify the investment.

Assuming SpaceX achieves economies of scale, that investment in expansion should reduce cost per unit, so maybe fairing costs would drop to 1.5 million. But a recovery and refurbishment operation should likely achieve more savings, although that is dependent on assumptions (this would exclude R&D cost)

Overall analysis gets much more complicated but could be simplified as:
Option 1: Production Expansion
+ XX CAPEX for new facilities & equipment / - Small X in cost per unit via economies of scale / No change in operational costs of launch

Options 2: Reuse
+YY (possibly equal or likely less than XX) for R&D of reuse / - Large Y in cost per unit via reuse (making it a depreciating asset across # of uses) / + small/medium Z in operational launch costs for recovery / refurbish


Its all trades, but basically you are aiming to invest in R&D instead of facilities and get lower cost per launch overall for the fairing's activities. Of interest based on SpaceX's aspirations. If they hope to exponentially increase launch rate (ie 24 a year soon, 50 a year soonish and daily eventually), every step up would require another new investment in fairing production facilities. So a new facility gets them to 25 a year, but need another big CAPEX to go to 50-100 etc. Whereas if they figure out how to reuse, they can minimize new CAPEX and have a more stable R&D budget to continually improve fairing recovery / refurbishment. So a company only ever hoping to go to 25 launches a year, may see a bigger factory as suitable, but a company that wants to get into the hundreds should start figuring out reuse.

Similar argument for why they have to achieve reuse of the first stage.
Title: Re: Fairing reuse
Post by: Zed_Noir on 06/08/2015 10:32 am
@Mariusuiram

SpaceX already expanded into some of the surrounding lots & buildings adjacent to their original Hawthorne facility. They are in need of of more floor space & parking space IMO. Especially if they stockpile bulky items like fairing & Falcon legs indoors.
Title: Re: Fairing reuse
Post by: iamlucky13 on 06/10/2015 02:13 am
I'm surprised though that fairing manufacturing is not dwarfed by second stage manufacturing.  I guess it isn't...

Fairings probably are dwarfed by second stage. That doesn't meant that fairings can't become a supply choke point.

With aircraft, you'd think bolts would be dwarfed by engines, or landing gear, or some other large, expensive system. Yet, several months of the delays of the Boeing 787 were created simply by the inability of suppliers to ramp up production of certain types of fasteners they needed. Deliveries of the same plane are currently being screwed up waiting on seats.

Uhm, the cost savings isn't as clear as that because recovery and refurbishment doesn't factor in having to make them (apparently) more robust in the first place as well as adding a recovery system.

How much more robust? The pictures show fairly good overall condition, aside from being broken up. The extra hardware might be as simple as a light coating of TPS, a cold gas system to orient it for entry (assuming it can't passively orient before peak heating and/or pressure) and a way to protect it from hitting the water too hard (parachute or parachute + helicopter).

Quote
The fairings are going to fall well away from the first stage recovery vehicles so that requires another set of recovery vehicles and personnel which adds costs.

Agreed on that point. You wouldn't want them staging close to the 1st stage ground track anyways, for safety.

Quote
(Second stage efficiency and reusability would to me seem a higher priority)

I would assume SpaceX is working on both 2nd stage recovery and fairing recovery concurrently. 2nd stage almost certainly has the higher potential value, but fairing is potentially a lower hanging fruit.

I don't see any wires coming out of that GoPro mount that could have carried the data to an antenna for downlink, so I'm pretty well convinced SpaceX was hoping their camera (or cameras, over multiple launches) would be recovered, presumably so they could study how the fairing behaves during entry and when it breaks up.
Title: Re: Fairing reuse
Post by: Doesitfloat on 10/14/2015 03:50 pm
Just got notification of sale of 20 Italian HH-3F-Pelican aircraft.
from Wikipedia:

In 1965, U.S. Coast Guard ordered a version designated, HH-3F Sea King (more commonly known by its nickname "Pelican") for all-weather air-sea rescue.[2] The Pelican featured a search radar with a nose antenna radome offset to port,[1][4] and water landing capability.[2]

Italian Agusta built a S-61R variant, named AS-61R under license. Agusta produced 22 helicopters for the Italian Air Force.[2] The company claimed it could re-open the production line in 36 months to build additional AS-61 helicopters.[5]

So, it's a big amphibious helicopter.  Isn't this what you would want to catch fairings and or have crew close to ASDS.

edit: The notification is that Italy is selling the aircraft; not that they are sold.
Title: Re: Fairing reuse
Post by: Moe Grills on 12/22/2015 02:53 am
Let me destroy a myth that has been passed off as a fact in recent years.

There is a persistent myth among many people, who should know better, that assume aircraft today and yesterday are and were nearly 100% reusable, when they are and were not.
First: a World War Two example: P51 Mustang fighters in that conflict flew off on long-range missions with COMPLETELY DISPOSABLE  fuel drop-tanks.
I won't even mention that all piston-engine aircraft after so many hours of flight, had to have their engines overhauled (many parts, pistons, etc., were disposed and replaced).
Today's passenger jets also need engine overhauls from time to time; not to mention that tires, brake pads, hydraulic components, etc. all get frequently replaced.
So why are some of you believing or dreaming of completely reusable spacecraft , when it will never happen? And doesn't need to happen to make space travel affordable?
Title: Re: Fairing reuse
Post by: JamesH on 12/22/2015 08:34 am
Let me destroy a myth that has been passed off as a fact in recent years.

There is a persistent myth among many people, who should know better, that assume aircraft today and yesterday are and were nearly 100% reusable, when they are and were not.
First: a World War Two example: P51 Mustang fighters in that conflict flew off on long-range missions with COMPLETELY DISPOSABLE  fuel drop-tanks.
I won't even mention that all piston-engine aircraft after so many hours of flight, had to have their engines overhauled (many parts, pistons, etc., were disposed and replaced).
Today's passenger jets also need engine overhauls from time to time; not to mention that tires, brake pads, hydraulic components, etc. all get frequently replaced.
So why are some of you believing or dreaming of completely reusable spacecraft , when it will never happen? And doesn't need to happen to make space travel affordable?

Well, by your definition, even a car is not reusable....

It all comes down to the cost of 'reusability', whatever the definition. It's cheaper to refurb the engine on an airliner than build a new airliner.
Title: Re: Fairing reuse
Post by: Comga on 12/23/2015 03:41 am
And I thought you people would be discussing whether there was a boat in the area where the fairings should have fallen, possibly looking for them, this being the Fairing Reuse thread.
Foolish me
Title: Re: Fairing reuse
Post by: mme on 12/23/2015 01:00 pm
Let me destroy a myth that has been passed off as a fact in recent years.

There is a persistent myth among many people, who should know better, that assume aircraft today and yesterday are and were nearly 100% reusable, when they are and were not.
First: a World War Two example: P51 Mustang fighters in that conflict flew off on long-range missions with COMPLETELY DISPOSABLE  fuel drop-tanks.
I won't even mention that all piston-engine aircraft after so many hours of flight, had to have their engines overhauled (many parts, pistons, etc., were disposed and replaced).
Today's passenger jets also need engine overhauls from time to time; not to mention that tires, brake pads, hydraulic components, etc. all get frequently replaced.
So why are some of you believing or dreaming of completely reusable spacecraft , when it will never happen? And doesn't need to happen to make space travel affordable?
I don't really understand the point of your post nor the myth you are "destroying."

SpaceX is actively looking into ways to recover and reuse the fairings.  This thread exists because of that effort.  SpaceX is concerned about being able to produce fairings fast enough if they achieve the sort of launch cadence that is their goal.  Also, the fairings cost a couple million dollars and SpaceX hopes to eventually get launch prices down to a point that a couple million dollars is noticeable.  The fact that there are some parts that are disposable, some will require replacement, and some will need repair is completely orthogonal to this thread.
Title: Re: Fairing reuse
Post by: cscott on 12/23/2015 02:11 pm
And I thought you people would be discussing whether there was a boat in the area where the fairings should have fallen, possibly looking for them, this being the Fairing Reuse thread.
Foolish me
That discussion is happening in the ASDS thread, where all the boat trackers hang out. Go Quest is believed to be on the hunt.

http://forum.nasaspaceflight.com/index.php?topic=36326.msg1463732.msg#1463732
Title: Re: Fairing reuse
Post by: CJ on 12/24/2015 05:30 am
This might be far fetched, but I can't help but wonder if a path to fairing reuse might be a change in outer layer (to resist seawater damage), a small drogue chute, and a water-activated radio pinger to enable finding them. 

My guess is the hardest part would be coming up with a way to make the fairing structure (a composite honeycomb) resist seawater damage, without increasing mass.

As for Go Quest, it definitely appears that it was out there looking for something. It appears to be inbound for Canaveral now.
Title: Re: Fairing reuse
Post by: Kabloona on 12/24/2015 09:43 am
Go Quest docked last night at Port Canaveral. Unfortunately timing was bad...she came in at night, and today is Christmas Eve, so few people will want to go over and take a look and see if she has any fairing halves on board...
Title: Re: Fairing reuse
Post by: Jim on 12/24/2015 04:22 pm
Fairings break up and don't come down in one piece.
Title: Re: Fairing reuse
Post by: Kabloona on 12/24/2015 05:04 pm
Fairings break up and don't come down in one piece.

With the GoPro cams and Elon's tweet in the first post of this thread, they're clearly looking at the possibility of recovering/reusing fairings at some point. This mission would have been a good one to try some recovery experiments on, though I don't know what method they might have in mind to keep the fairing intact.

If they didn't find an intact fairing half, at least they may have found a large piece with the GoPro cam on it.
Title: Re: Fairing reuse
Post by: OxCartMark on 12/24/2015 05:24 pm
Fairings break up and don't come down in one piece.

So do rockets if they're not designed to be reusable.
Title: Re: Fairing reuse
Post by: OxCartMark on 12/24/2015 05:26 pm
Fairings break up and don't come down in one piece.

Well, I'll give you this - I know you're right on one level because I saw it break into two pieces during the webcast.
Title: Re: Fairing reuse
Post by: kch on 12/24/2015 05:48 pm
Go Quest docked last night at Port Canaveral. Unfortunately timing was bad...she came in at night, and today is Christmas Eve, so few people will want to go over and take a look and see if she has any fairing halves on board...

Seems like it'd be pretty quiet there today ... might be a good time to go halve a look.  ;)
Title: Re: Fairing reuse
Post by: Comga on 12/26/2015 05:55 pm
Fairings break up and don't come down in one piece.

Well, I'll give you this - I know you're right on one level because I saw it break into two pieces during the webcast.

I wrote a long reply before realizing that your post is a lame joke missing the smiley face.
It did give me an unneeded excuse to rewatch the launch video.
As for Jim's comment, fairings did break up and come down in pieces.  First stages also fell in the ocean.
Unless that was Jim's idea of a bone-dry joke, too.
How could we tell?
Title: Re: Fairing reuse
Post by: cscott on 12/26/2015 07:10 pm
I'm pretty sure no one expects that Go Quest recovered a complete, intact, and reusable fairing from this mission.  But fairing fragments have washed up before, and Go Quest might have managed to locate some---or at least the piece which has the radio beacon and instrument package on it (if indeed some experiment of that sort was flown).
Title: Re: Fairing reuse
Post by: oiorionsbelt on 12/26/2015 07:49 pm
I'm pretty sure no one expects that Go Quest recovered a complete, intact, and reusable fairing from this mission.  But fairing fragments have washed up before, and Go Quest might have managed to locate some---or at least the piece which has the radio beacon and instrument package on it (if indeed some experiment of that sort was flown).
Go Quest would not be out looking for the fairing if they didn't intend to learn something from the pieces. The have found quite a few pieces already. What could have changed from the last mission to make them them want to go look for it?
 I'm not convinced GQ was looking for the fairing but if it was there must be something 'new' about this fairing.
Title: Re: Fairing reuse
Post by: Avron on 12/26/2015 08:04 pm
I'm pretty sure no one expects that Go Quest recovered a complete, intact, and reusable fairing from this mission.  But fairing fragments have washed up before, and Go Quest might have managed to locate some---or at least the piece which has the radio beacon and instrument package on it (if indeed some experiment of that sort was flown).
Go Quest would not be out looking for the fairing if they didn't intend to learn something from the pieces. The have found quite a few pieces already. What could have changed from the last mission to make them them want to go look for it?
 I'm not convinced GQ was looking for the fairing but if it was there must be something 'new' about this fairing.

might be looking for that GoPro https://www.youtube.com/watch?v=4_sLTe6-7SE
Title: Re: Fairing reuse
Post by: ugordan on 12/26/2015 08:07 pm
might be looking for that GoPro

For those awesome shots of pitch-black darkness?
Title: Re: Fairing reuse
Post by: Jakusb on 12/26/2015 08:22 pm

Fairings break up and don't come down in one piece.

You mean: they used to, until some all daring new entrant challenged all status quo, carefully build up in the last 40 years.... ;)
Title: Re: Fairing reuse
Post by: Avron on 12/26/2015 08:24 pm
might be looking for that GoPro

For those awesome shots of pitch-black darkness?

we don't know that, I would suspect some data gathering of the fairing behaviour with this new  vehicle.
Title: Re: Fairing reuse
Post by: Ixian77 on 12/26/2015 09:13 pm
Fairings could retract back down along side second stage skin, in six segments. Deploy payload.
Then, after nose mounted superdracos fire to reorient second stage, fairing redeploy to act as TPS for reentry. As superdracos fire to land second stage, fairing partial retractment to act as landing legs.

You're welcome.
Title: Re: Fairing reuse
Post by: cscott on 12/26/2015 10:06 pm
That ignores the rocket equation: the fairing is a substantial mass thus wants to separate from the payload at the earliest possible opportunity.
Title: Re: Fairing reuse
Post by: Comga on 12/26/2015 10:23 pm
Fairings could retract back down along side second stage skin, in six .....(snip)

You're welcome.
for nothing
Are you missing your winking emoticon?
If not, please stop with the Fireball XL5 / James Bond space prop descriptions.
Some of us are trying to be serious here.
Title: Re: Fairing reuse
Post by: AJW on 12/27/2015 06:04 am
I'm pretty sure no one expects that Go Quest recovered a complete, intact, and reusable fairing from this mission.  But fairing fragments have washed up before, and Go Quest might have managed to locate some---or at least the piece which has the radio beacon and instrument package on it (if indeed some experiment of that sort was flown).
Go Quest would not be out looking for the fairing if they didn't intend to learn something from the pieces. The have found quite a few pieces already. What could have changed from the last mission to make them them want to go look for it?
 I'm not convinced GQ was looking for the fairing but if it was there must be something 'new' about this fairing.

One significant change is that GQ didn't have a specific role in an RTLS flight, so if the resource is available, retask it.   If you want to study fairing reuse, start by recovering a fairing from a flight and see what you can learn from it.  And yes, pieces of fairings have been recovered, but typically months, or even a year later when they have been subjected to other kinds of damage.
Title: Re: Fairing reuse
Post by: OxCartMark on 12/29/2015 04:05 am
Have we touched on how fairings get transported from Hawthorne to the distant launch sites?  They are 5M in diameter and if shipped in two halves you are going to have a load that's either 5M high (too high for bridges even without a trailer underneath) or 5M wide (obnoxiously wide but maybe possible with permits and convoy) or some awkward diagonal compromise.  Are they really shipped in halves or perhaps they might be in quarter circle slivers that are joined at the launch site.  If this is as big of a transportation problem as I'm thinking that would be another contributor (besides cost) to the desire to achieve fairing reusability.

And its been mentioned that fairing fabrication takes up a lot of space in Hawthorne and that SpaceX is beginning to run out of factory floorspace in Hawthorne (its landlocked).  It seems to me that fairing fabrication (whether in a disposable or reusable scenario) is decoupled from other manufacturing processes in Hawthorne enough that it would be a good candidate for being moved to another or multiple other facilities (perhaps closer to launch sites).
Title: Re: Fairing reuse
Post by: oiorionsbelt on 12/29/2015 04:27 am
Have we touched on how fairings get transported from Hawthorne to the distant launch sites?  They are 5M in diameter and if shipped in two halves you are going to have a load that's either 5M high (too high for bridges even without a trailer underneath) or 5M wide (obnoxiously wide but maybe possible with permits and convoy) or some awkward diagonal compromise. .
This was just posted somewhere here but here it is again.
Title: Re: Fairing reuse
Post by: QuantumG on 12/29/2015 05:26 am
Ya know, it does basically look like a boat..
Title: Re: Fairing reuse
Post by: kch on 12/29/2015 05:55 am
Ya know, it does basically look like a boat..

That it does.  I wonder if it might be able to generate lift (and perhaps be controllable), if properly oriented?
Title: Re: Fairing reuse
Post by: Zed_Noir on 12/29/2015 06:29 am
Ya know, it does basically look like a boat..

That it does.  I wonder if it might be able to generate lift (and perhaps be controllable), if properly oriented?

If someone add some pop out cold gas attitude thrusters to a PLF segment for some test drops.
Title: Re: Fairing reuse
Post by: rds100 on 12/29/2015 07:16 am

So is the fairing that expensive, to be worth the extra effort needed for reusing? I thought it's a fairly simple shell which can be machine fabricated, so shouldn't be very expensive.
Title: Re: Fairing reuse
Post by: Darkseraph on 12/29/2015 07:22 am
I expect a propellant reuse thread any day soon... ;D


In all seriousness I don't think an off hand tweet is proof SpaceX are pouring very much effort into fairing reuse. They have already given up on second stage reuse for the Falcon 9 because it is more hassle than it is worth on this generation of vehicles. Fairings are bound to be a lot cheaper to construct than engines so making disposable fairings cheaper and/or lighter is probably a better use of time in the near term.

Some future vehicle with a reusable second stage could have a payload bay like the X37b/Shuttle. That won't be happening anytime soon though.  :/
Title: Re: Fairing reuse
Post by: QuantumG on 12/29/2015 09:35 am
Last I heard they weren't even making them anymore. The kilns are not even at Hawthorn anymore are they?
Title: Re: Fairing reuse
Post by: MarekCyzio on 12/29/2015 11:45 am
In all seriousness I don't think an off hand tweet is proof SpaceX are pouring very much effort into fairing reuse.

It is always a question of economics. Fairing may be relatively cheap, but also relatively easy to recover. It gets dropped at relatively low speeds, short exposures to saltwater do not cause significant damage, It only needs some simple systems to stabilize its descent (cold gas thrusters?, small aero fins or grids?), cushion water impact (drogue shute?) and keep it afloat for some time (baloons?). I am pretty sure SpaceX engineers are actively looking into this.
Title: Re: Fairing reuse
Post by: Johnnyhinbos on 12/29/2015 11:55 am
I know fairings are relatively simple structures, but I would venture to say they are deceptively simple structures. They are, after all, the sharp end of the sward - they take the bulk of the air pressure (I believe) during launch and if think a failure in the fairing would really ruin someone's day. Large composites are difficult to manufacture as well as labor intensive and slow production rates. All that, to me, spells a compelling reason to strive for reuse.
Title: Re: Fairing reuse
Post by: sublimemarsupial on 12/29/2015 02:53 pm
Last I heard they weren't even making them anymore. The kilns are not even at Hawthorn anymore are they?

They are very much still making them, the tooling and ovens are quite a prominent sight on tours, and there's always a couple halves in work.
Title: Re: Fairing reuse
Post by: LouScheffer on 12/29/2015 04:12 pm

So is the fairing that expensive, to be worth the extra effort needed for reusing? I thought it's a fairly simple shell which can be machine fabricated, so shouldn't be very expensive.

ULA and Ariane buy fairings from RUAG, a European company.  Although the contracts are not super specific, they seem to indicate 5-6 million per fairing..  The post that discusses this is here:   http://forum.nasaspaceflight.com/index.php?topic=37727.msg1384676#msg1384676   This is not a huge fraction at current prices, but could become so if re-use works as hoped.
Title: Re: Fairing reuse
Post by: Robotbeat on 12/30/2015 12:04 am
Way back in the day when Falcon 9 was supposed to have half the current performance, the cost of the big 5m fairing was a significant portion of the launch cost:

http://www.space.com/1533-spacex-tackle-fully-reusable-heavy-lift-launch-vehicle.html
Quote
In the medium configuration, Falcon 9 would be priced at $27 million per flight with a 12 ft (3.6 m) fairing and $35 million with a 17 ft fairing.

...a difference of $8 million(!), which is more than the projected per-launch costs of a fully reusable Falcon 9 back when a reusable 2nd stage for Falcon 9 was still seriously on the table. And keep in mind that's the DIFFERENCE in price between the smaller (aluminum, I think) fairing and the larger fairing.

Some of that no doubt is market segmentation and differences in handling difficulty, but it seems safe to say that a large composite fairing could correspond to several million dollars in fabrication costs.

So yeah, once SpaceX is launching like 40+ flights per year as SpaceX intends to do over the next 5+ years, you're talking hundreds of millions of dollars in fairings just thrown away. It may indeed make sense to start recovering them if it's not too difficult.
Title: Re: Fairing reuse
Post by: QuantumG on 12/30/2015 12:10 am
They are very much still making them, the tooling and ovens are quite a prominent sight on tours, and there's always a couple halves in work.

Thanks. Is it still next to the coffee cart?
Title: Re: Fairing reuse
Post by: Comga on 12/30/2015 05:52 am

So is the fairing that expensive, to be worth the extra effort needed for reusing? I thought it's a fairly simple shell which can be machine fabricated, so shouldn't be very expensive.

ULA and Ariane buy fairings from RUAG, a European company.  Although the contracts are not super specific, they seem to indicate 5-6 million per fairing..  The post that discusses this is here:   http://forum.nasaspaceflight.com/index.php?topic=37727.msg1384676#msg1384676 (http://forum.nasaspaceflight.com/index.php?topic=37727.msg1384676#msg1384676)   This is not a huge fraction at current prices, but could become so if re-use works as hoped.

Ms Shotwell once said (don't have the reference handy) $6-7M for an RTLS Falcon 9.
That surely does not include disposing of a $5-6M fairing, even if SpaceX makes it for half that cost
Title: Re: Fairing reuse
Post by: OxCartMark on 03/07/2016 03:34 am
I'm hoping to move the recent discussion of the fairings to this dormant thread.  During the launch of SES-9 it there was a 2nd support ship, Go Searcher out which some speculated was for fairing recovery.  Then some commented that they saw puffs of thrust coming from the fairing halves.  I hope that its true but in the two great videos I've seen that show the fairing halves I'm not seeing it.  Thoughts / comments / observations?  Below are some posts I'm copying here for background.  There are other posts on this subject elsewhere as well.

So with the RCS visible from the fairings in launch video does it reinforce that GO Searcher is out supporting fairing recovery experiments?

That would be nice.  I've heard rumor of jets from the fairing halves in three places now but not seen it.  Can someone link the video?

edit: suggest we move any fairing discussion if it erupts into the fairing recovery thread that has been dormant for a while.  http://forum.nasaspaceflight.com/index.php?topic=37727.0

This video has a good view of the jets:  https://www.youtube.com/watch?v=3yuq8nUSdtY

edit: OK, we have the times to look for -
Puffs from the upper fairing half at 5:20 and 5:27.  Discuss, you know you want to.

edit2: Yes, I'm buying it, it appears that way.  Fairing seperated around 4:40 youtube time so at 5:20 the fairing had been off for 40 seconds and by the next puff 47 seconds.  By then the 2nd stage should have moved well ahead and we shouldn't be seeing exhaust impingement.
Title: Re: Fairing reuse
Post by: Robotbeat on 03/07/2016 04:10 am
I could not see the puffs in question. Can you take a screenshot or series of stills to highlight what you believe is puffs from the fairing?? Even better would be a zoomed-in and stabilized GIF or video...
Title: Re: Fairing reuse
Post by: Ilikeboosterrockets on 03/07/2016 04:27 am
At 5:00 you can see 4 bright objects on the frame. The top object (in the frame) is a fairing, the one below that is the second stage, the one below that is the other fairing half, and the object near the bottom is the first stage. At 5:03 you can see a puff from the first stage, which is a GN2 ACS thruster firing to reorient the stage for reentry.

At 5:20, you can kinda see a small puff from the top fairing directed downwards. At 5:27, just as the camera is focussing back you can see a big puff from the top fairing (which has by now fallen below the second stage) directed towards the left of the screen.
Title: Re: Fairing reuse
Post by: CJ on 03/07/2016 04:36 am
I spotted one puff (there may have been others) from a fairing half. It looked just like the N2 puffs we see (and have seen before) from the first stage when it's maneuvering post-MECO, only weaker.

Seeing as how there aren't any known gas bottles on the fairings (?) IMHO, this is evidence of something new on the fairings, and probably to do with recovery.     

I can't get it to show well in a screengrab, and I can't edit video or make GIFs from one. If you watch the vid, make sure to set it to HD or you won't see it. The puff occurs at 5:27 and emanates from the upper fairing half, and moves right to left.

 
Title: Re: Fairing reuse
Post by: dorkmo on 03/07/2016 04:47 am
I could not see the puffs in question. Can you take a screenshot or series of stills to highlight what you believe is puffs from the fairing?? Even better would be a zoomed-in and stabilized GIF or video...

around 5:20 youtube time, there appears to be one main puff then maybe a short one immediately following, then a third right as the camera pans down.

at 5:28 there is a single puff.

i think there might be two small puffs simultaniously at 5:08 on the upper fairing.
Title: Re: Fairing reuse
Post by: dorkmo on 03/07/2016 05:06 am
ill mention that it seems like only one of the fairing halves is puffing. if this is indeed manuvering perhaps they are only testing one half to save weight.

personally i dont think there is enough evidence to say go searcher was for fairing recovery. though it could be possible.
Title: Re: Fairing reuse
Post by: OnWithTheShow on 03/07/2016 05:12 am
Here is a gif
Title: Re: Fairing reuse
Post by: Jdeshetler on 03/07/2016 06:43 am
Stabilized and close up...
Title: Re: Fairing reuse
Post by: thor1872 on 03/07/2016 06:54 am
may be this can help

Fairing Jason-3
https://imgur.com/a/anZ4r
Source:
https://www.flickr.com/photos/nasakennedy/sets/72157651824508130

edit: I just saw that if you zoom in, you can see some black round, they hide something.
Title: Re: Fairing reuse
Post by: WBY1984 on 03/07/2016 07:22 am
Can't quite understand what you're getting at: If you zoom in *where*, we see a black round *what*?
Title: Re: Fairing reuse
Post by: thor1872 on 03/07/2016 08:26 am
Can't quite understand what you're getting at: If you zoom in *where*, we see a black round *what*?
https://imgur.com/lUPlvL9  ;)
Title: Re: Fairing reuse
Post by: ugordan on 03/07/2016 08:29 am
Those would be separation joints/pushers. It's just your regular eyetar censorship.
Title: Re: Fairing reuse
Post by: woods170 on 03/07/2016 10:50 am
Those would be separation joints/pushers. It's just your regular eyetar censorship.
No, not even that. Proprietary censorship. Blanking out the details in those images was done by SpaceX itself. They are the source for those images.
Title: Re: Fairing reuse
Post by: ugordan on 03/07/2016 10:52 am
Those would be separation joints/pushers. It's just your regular eyetar censorship.
No, not even that. Proprietary censorship.

Perhaps, but eyetar sure comes in handy as an excuse.
Title: Re: Fairing reuse
Post by: WBY1984 on 03/07/2016 11:58 am
So we've seen what might be RCS pulses coming from a fairing. My question is how does attitude control help recovery? I have no expertise, but why wouldn't you just stick a parachute on the thing and maybe a floatation device?
Title: Re: Fairing reuse
Post by: Robotbeat on 03/07/2016 12:19 pm
Stabilized and close up...
Wow, you all sure delivered!

There can be no question. Those look precisely like thruster firings.

They need thrusters to orient the fairings to come in at the correct orientation.

This is all fascinating. SpaceX continues to make surprising steps forward in reuse even when almost everyone else wouldn't bother. Bravo!
Title: Re: Fairing reuse
Post by: Chris Bergin on 03/07/2016 12:35 pm
I'm pulling this face:

(http://i.kinja-img.com/gawker-media/image/upload/s--D8CQa-Ot--/18gscgz2z6pnrjpg.jpg)

Didn't get any pre-note about this element (unlike the ballsy first stage landing attempt under three engines). I'm asking around, however!
Title: Re: Fairing reuse
Post by: WBY1984 on 03/07/2016 12:39 pm


They need thrusters to orient the fairings to come in at the correct orientation.



I guess what I'm asking is why do the fairings need to maintain a particular orienation at all? They aren't seperating much higher/faster than stage 1 MECO, and the fairings are both big and light, so I can't imagine they're all that thermally stressed on reentry. Why not let them tumble until parachute altitude?
Title: Re: Fairing reuse
Post by: R7 on 03/07/2016 12:45 pm
I guess what I'm asking is why do the fairings need to maintain a particular orienation at all? They aren't seperating much higher/faster than stage 1 MECO, and the fairings are both big and light, so I can't imagine they're all that thermally stressed on reentry. Why not let them tumble until parachute altitude?

Allowing something big, light and aerodynamically unstable to freely tumble in hypersonic wind is a good recipe for destructive mechanical stresses.
Title: Re: Fairing reuse
Post by: WBY1984 on 03/07/2016 12:48 pm
Thanks :)
Title: Re: Fairing reuse
Post by: OxCartMark on 03/07/2016 12:59 pm
what I'm asking is why do the fairings need to maintain a particular orienation at all?...Why not let them tumble until parachute altitude?

Buncha speculations:
- Because they've modeled the re-entry and found that one orientation is better than others
- Because they want to expose the outside surface which is not very heat tolerant epoxy to the heat rather than the inside surface which has expanded foam which is even less heat tolerant.
- Because they fly a predictable stable path if you get them concave down rather than tumbling and producing a less predictable landing point otherwise
- Because their longer range plan if they can get through re-entry is to add control surfaces to "fly" them through the lower atmosphere to a designated point for collection and you need to get them to a stable orientation to start that process

Separate observation: I find it interesting that the fairings are so far separated considering that their separation speed isn't that great and there is little aerodynamic influence.

What cameras or other resources do we have available in Port Canaveral to see if they were successful?
Title: Re: Fairing reuse
Post by: dorkmo on 03/07/2016 12:59 pm
Can't quite understand what you're getting at: If you zoom in *where*, we see a black round *what*?
https://imgur.com/lUPlvL9  ;)

not sure if its related but it looks like there is the top of a COPV with a pipe coming out right above the right shoulder of the guy on the right in blue jumpsuit.
Title: Re: Fairing reuse
Post by: Jim on 03/07/2016 01:29 pm
seeing as how there aren't any known gas bottles on the fairings

There are and this could be the system breaching from aero affects
Title: Re: Fairing reuse
Post by: WBY1984 on 03/07/2016 01:39 pm
seeing as how there aren't any known gas bottles on the fairings

There are and this could be the system breaching from aero affects

Yeah, seems just as likely as RCS to me. Should be skeptical until we know more.
Title: Re: Fairing reuse
Post by: ugordan on 03/07/2016 01:42 pm
seeing as how there aren't any known gas bottles on the fairings

There are and this could be the system breaching from aero affects

A mere 50 or so seconds after fairing sep? Unlikely. The thing was likely to still be way up above the atmosphere at that time.

Edit: trajectory analysis (https://plot.ly/~iannis/folder/iannis:96) by Reddit user ianniss shows fairing sep at a velocity of around 2.5 km/s, velocity angle around 13 deg above horizontal. The vertical displacement from faring sep altitude is then:

sin(13 deg)*2500m/s*50s - 10m/s /2*50s*50s = 28 km upward - 12.5 km downward. So the fairing halves were, in fact, still coasting up at that point.

The gas might have been autonomously vented, but aeroloads it wasn't.
Title: Re: Fairing reuse
Post by: thor1872 on 03/07/2016 01:44 pm
Can't quite understand what you're getting at: If you zoom in *where*, we see a black round *what*?
https://imgur.com/lUPlvL9  ;)

not sure if its related but it looks like there is the top of a COPV with a pipe coming out right above the right shoulder of the guy on the right in blue jumpsuit.
well seen
https://imgur.com/aRsIuDm
Title: Re: Fairing reuse
Post by: Jim on 03/07/2016 02:09 pm
seeing as how there aren't any known gas bottles on the fairings

There are and this could be the system breaching from aero affects

A mere 50 or so seconds after fairing sep? Unlikely. The thing was likely to still be way up above the atmosphere at that time.

Edit: trajectory analysis (https://plot.ly/~iannis/folder/iannis:96) by Reddit user ianniss shows fairing sep at a velocity of around 2.5 km/s, velocity angle around 13 deg above horizontal. The vertical displacement from faring sep altitude is then:

sin(13 deg)*2500m/s*50s - 10m/s /2*50s*50s = 28 km upward - 12.5 km downward. So the fairing halves were, in fact, still coasting up at that point.

The gas might have been autonomously vented, but aeroloads it wasn't.

Or the actual separation event.

https://www.youtube.com/watch?v=5r5me6mTQb4
Title: Re: Fairing reuse
Post by: obsever on 03/07/2016 02:16 pm
seeing as how there aren't any known gas bottles on the fairings

There are and this could be the system breaching from aero affects

A mere 50 or so seconds after fairing sep? Unlikely. The thing was likely to still be way up above the atmosphere at that time.

Edit: trajectory analysis (https://plot.ly/~iannis/folder/iannis:96) by Reddit user ianniss shows fairing sep at a velocity of around 2.5 km/s, velocity angle around 13 deg above horizontal. The vertical displacement from faring sep altitude is then:

sin(13 deg)*2500m/s*50s - 10m/s /2*50s*50s = 28 km upward - 12.5 km downward. So the fairing halves were, in fact, still coasting up at that point.

The gas might have been autonomously vented, but aeroloads it wasn't.

Or the actual separation event.

...

Wouldn't it be a lot less violent on F9 compared to Atlas, since they are using a non-pyrotechnic method (pushers) on F9 ?

Edit: in the video from the test the separation event looks more smooth than the Atlas one you linked above:

https://www.youtube.com/watch?v=LtI1V624vWM
Title: Re: Fairing reuse
Post by: Flying Beaver on 03/07/2016 02:46 pm
The Helium bottles used for pneumatic fairing sep are pictured here (from Nov 2012):

https://www.flickr.com/photos/jurvetson/8233306859/
Title: Re: Fairing reuse
Post by: Ilikeboosterrockets on 03/07/2016 02:53 pm
I'm wondering if it was those helium bottles leaking instead of thrusters. Is there any difference in the visibility of helium outgassing vs. something like nitrogen?
Title: Re: Fairing reuse
Post by: Flying Beaver on 03/07/2016 03:05 pm
I'm wondering if it was those helium bottles leaking instead of thrusters. Is there any difference in the visibility of helium outgassing vs. something like nitrogen?

I might be mistaken, but in a vacuum Nitrogen freezes and produces ice crystals (hence the name "Cold Gas Thrusters" on the first stage). Where as helium simply disperses invisibly.
Title: Re: Fairing reuse
Post by: Robotbeat on 03/07/2016 03:17 pm
I'm wondering if it was those helium bottles leaking instead of thrusters. Is there any difference in the visibility of helium outgassing vs. something like nitrogen?
Although helium does not condense, I wouldn't expect a visible sign from helium venting, but... That is the best alternative explanation I've heard so far.

But it might not even be contradictory. They may be venting what's left in the bottles out through a nozzle to test some aspect of fairing recovery hardware.

Do we know for a fact the pushers use helium and not nitrogen?
Title: Re: Fairing reuse
Post by: Jim on 03/07/2016 03:25 pm

I might be mistaken, but in a vacuum Nitrogen freezes and produces ice crystals (hence the name "Cold Gas Thrusters" on the first stage). Where as helium simply disperses invisibly.

No, nitrogen does not freeze nor does it contain any water.  Any gas venting in a vacuum would be visible
Title: Re: Fairing reuse
Post by: Saabstory88 on 03/07/2016 03:45 pm
Maybe this is a stupid question, but wouldn't the fairing half passing through the second stage plume also create an effect like this?
Title: Re: Fairing reuse
Post by: ugordan on 03/07/2016 03:48 pm
Maybe this is a stupid question, but wouldn't the fairing half passing through the second stage plume also create an effect like this?

There would be around 10 km distance between the fairing and engine around 50 seconds after fairing sep. Highly unlikely.
Title: Re: Fairing reuse
Post by: AS-503 on 03/07/2016 03:51 pm

I might be mistaken, but in a vacuum Nitrogen freezes and produces ice crystals (hence the name "Cold Gas Thrusters" on the first stage). Where as helium simply disperses invisibly.

No, nitrogen does not freeze nor does it contain any water.  Any gas venting in a vacuum would be visible

Then I am puzzled why most upper stage exhaust plumes are not visible?
Title: Re: Fairing reuse
Post by: Saabstory88 on 03/07/2016 03:57 pm
Maybe this is a stupid question, but wouldn't the fairing half passing through the second stage plume also create an effect like this?

There would be around 10 km distance between the fairing and engine around 50 seconds after fairing sep. Highly unlikely.

I mention this because we only see the "thrusts" from the fairing half which appears to be trailing in the second stage exhaust plumes. I mean, of course, this is SpaceX we are talking about, but I'm just trying to remain skeptical. What's more likely, that only one of the fairings needs to complete maneuvers, or that the fairing caught in the plume redirects some gas as it spins in free fall?
Title: Re: Fairing reuse
Post by: Hauerg on 03/07/2016 03:58 pm
They only test with one half. The other is a point of reference.
Title: Re: Fairing reuse
Post by: pippin on 03/07/2016 04:08 pm
If this is really a reuse experiment, are they trying to land the fairing without a parachute? I mean... Given the shape and lightness it _should_ be possible to use that thing as a wing if they find a way to get enough control authority
Title: Re: Fairing reuse
Post by: Kabloona on 03/07/2016 04:10 pm
They only test with one half. The other is a point of reference.

Yes, logical explanation for why gas jet is visible from only one fairing half.
Title: Re: Fairing reuse
Post by: ugordan on 03/07/2016 04:16 pm
Another thing is that only one half of the fairing contains the gas bottles for the sep pushers. Easier to outfit that one with ACS than introduce gas bottles to the other half as well.
Title: Re: Fairing reuse
Post by: Jim on 03/07/2016 04:26 pm
Another thing is that only one half of the fairing contains the gas bottles for the sep pushers. Easier to outfit that one with ACS than introduce gas bottles to the other half as well.

Or it is the only half that can leak gas, since the other doesn't have bottles.
Title: Re: Fairing reuse
Post by: ugordan on 03/07/2016 04:44 pm
Another thing is that only one half of the fairing contains the gas bottles for the sep pushers. Easier to outfit that one with ACS than introduce gas bottles to the other half as well.

Or it is the only half that can leak gas, since the other doesn't have bottles.

http://forum.nasaspaceflight.com/index.php?topic=34077.msg1500497#msg1500497

Title: Re: Fairing reuse
Post by: dorkmo on 03/07/2016 07:09 pm

I might be mistaken, but in a vacuum Nitrogen freezes and produces ice crystals (hence the name "Cold Gas Thrusters" on the first stage). Where as helium simply disperses invisibly.

No, nitrogen does not freeze nor does it contain any water.  Any gas venting in a vacuum would be visible

Then I am puzzled why most upper stage exhaust plumes are not visible?

im not an expert but i believe it has to do with the short amount of time it takes for the gas to dissipate in the vacuum.
Title: Re: Fairing reuse
Post by: Nomadd on 03/07/2016 07:14 pm
 I don't believe that venting gas is visible. The liquid or ice that it turns into is visible.
Title: Re: Fairing reuse
Post by: matthewkantar on 03/07/2016 08:16 pm
The exhaust plume from the second stage seems huge, maybe what is observed is the vented gas displacing the plume, not the gas itself.

Matthew
Title: Re: Fairing reuse
Post by: llanitedave on 03/07/2016 10:05 pm
I guess what I'm asking is why do the fairings need to maintain a particular orienation at all? They aren't seperating much higher/faster than stage 1 MECO, and the fairings are both big and light, so I can't imagine they're all that thermally stressed on reentry. Why not let them tumble until parachute altitude?

Allowing something big, light and aerodynamically unstable to freely tumble in hypersonic wind is a good recipe for destructive mechanical stresses.


Is it possible that what we're seeing is fragmentation of some of the fairing internals, for instance, the softer insulation materials, under re-entry stresses?  Or is it too early in the sequence for that?


Edit: After reading the posts following the one I quoted I agree this is unlikely.
Title: Re: Fairing reuse
Post by: Kabloona on 03/07/2016 10:22 pm
Support ships GO Quest and GO Searcher have returned to port, with no fairing pieces visible on deck. So I lost my dollar bet...
Title: Re: Fairing reuse
Post by: Jim on 03/08/2016 01:20 am
I don't believe that venting gas is visible. The liquid or ice that it turns into is visible.

http://history.nasa.gov/SP-4206/ch12.htm
Title: Re: Fairing reuse
Post by: dorkmo on 03/08/2016 01:37 am
just some "duh" thoughts...

since the latch mechanism has a pretty heavy duty gas supply, it seems like there would always be some gas left over as margin. adding thrusters could mean tapping into an existing infrastructure. for not much added weight they can play around till the gas is depleted.
Title: Re: Fairing reuse
Post by: Jim on 03/08/2016 01:44 am
just some "duh" thoughts...

since the latch mechanism has a pretty heavy duty gas supply,

it may be high pressure but it would be a small amount of gas
Title: Re: Fairing reuse
Post by: intrepidpursuit on 03/08/2016 04:37 am
If they are doing reentry control testing with the fairings, I highly doubt they would touch the existing fairing separation system. If something goes wrong with that the mission fails. They would put in a separate system for the reuse functions and not mess with the fairing sep that has worked perfectly every time. I also don't see why they would vent helium in this case. Once the fairing separates it is gone, why do they care if there is a half full helium tank on it?

The video looks very, very much like the nitrogen thrusters firing around the same time from the first stage. I doubt they would do this on just one fairing half though, they have plenty of data on the fairings falling. Seems odd too that they would separate in such an orientation that one fairing half is above the other, as opposed to jettisoning them side to side. Then one has to fall back through the plume and the other doesn't. Perhaps the plume is hitting the stage and causing it to tumble, so we see irregular plume interference based on the orientation of the fairing.

I hope it is fairing reuse, and the evidence is somewhat compelling. But I'm not yet convinced.
Title: Re: Fairing reuse
Post by: rst on 03/08/2016 08:30 pm
If they are doing reentry control testing with the fairings, I highly doubt they would touch the existing fairing separation system. If something goes wrong with that the mission fails.

That depends, to some extent, on what modifications we're talking about.  If it involves changing the number or positioning of thrusters, that's risky.  If, on the other hand, it involves just giving the pre-existing thrusters bigger propellant tanks, perhaps less so...
Title: Re: Fairing reuse
Post by: Chris_Pi on 03/08/2016 09:11 pm
That depends, to some extent, on what modifications we're talking about.  If it involves changing the number or positioning of thrusters, that's risky.  If, on the other hand, it involves just giving the pre-existing thrusters bigger propellant tanks, perhaps less so...

Separation is done with pushers - A few pages back there's video of a separation test where they can be seen. Any attitude control stuff would be additional to that. Could be entirely separate, Could be tied in to the gas supply and using whatever leftovers there after separation. That would allow limited tests with very little weight added.
Title: Re: Fairing reuse
Post by: OxCartMark on 03/09/2016 03:50 pm
Separation is done with pushers

I've always known it was done with pushers and I think N gas pushers but I'm surprised by the technology path they've chosen. I always assumed that they used COTS nitrogen gas springs of the type used in automotive lift gates or the type used in stamping dies.  In my scenario the halves would be held together with electrically releasable latches such as on car trunks.  I guess those assumptions show the field that I've been working in.  But also now see that if they'd have chosen the path that I envision there'd be challenges in bringing the fairing halves together evenly against the multiple springs.
Title: Re: Fairing reuse
Post by: sghill on 03/10/2016 03:47 pm
Why not develop a fairing that peels back like a banana peel and locks against the second stage skin? Kind of like the legs, but in reverse.

It could be used as a TPS for the second stage so the stage can be recovered.
Title: Re: Fairing reuse
Post by: Jim on 03/10/2016 03:53 pm
Why not develop a fairing that peels back like a banana peel and locks against the second stage skin? Kind of like the legs, but in reverse.

It could be used as a TPS for the second stage so the stage can be recovered.

No need to peel it back if it is taken to orbit.  It could be opened right before spacecraft deployment.  But the fairing would reduce payload mass.
Title: Re: Fairing reuse
Post by: CyndyC on 03/10/2016 04:28 pm
Why not develop a fairing that peels back like a banana peel and locks against the second stage skin? Kind of like the legs, but in reverse.

It could be used as a TPS for the second stage so the stage can be recovered.

No need to peel it back if it is taken to orbit.  It could be opened right before spacecraft deployment.  But the fairing would reduce payload mass.

Bouncing off these 2 posts and after reading most everything in the L2 thread on the subject, why not just close the thing back up, and recover stage 2 and the fairing together. During the time the fairing is hanging open for payload separation, the aerodynamics would be related to opening a convertible top while driving, which I was told to never do because it would act like a sail and flip the car, but in space, there you have your boostback maneuver.

Edit: Maybe forget the last part since I just remembered there's little to no air that high, but maybe the shifts in mass could be used to assist in boostback.
Title: Re: Fairing reuse
Post by: Robotbeat on 03/10/2016 05:39 pm
 Atlas has its 5 m faring attached to the first stage. Something like that might make sense for a reasonable fairing since you don't have to take the whole thing to orbit. It would also protect the thermal protection system on the upper stage from water ingress  and condensation while it's sitting on the pad .
Title: Re: Fairing reuse
Post by: OxCartMark on 03/10/2016 05:59 pm
Rough numbers but you get the idea;

What's F9's payload capacity to GTO?  10,000 pounds?
What's the weight of the payload fairing?  5,000 pounds?
What's the revised payload capacity if you take the payload fairing along for the whole ride?  ?5000? pounds.

Substitute in actual numbers and you get actually poor numbers.  Weight carried on the first stage is not good.  Weight carried on the second stage is really not good.
Title: Re: Fairing reuse
Post by: mfck on 03/10/2016 06:25 pm
Atlas has its 5 m faring attached to the first stage. Something like that might make sense for a reasonable fairing since you don't have to take the whole thing to orbit. It would also protect the thermal protection system on the upper stage from water ingress  and condensation while it's sitting on the pad .
Am I right to remember that AV booster separates much higher and at a higher speed?
Title: Re: Fairing reuse
Post by: RanulfC on 03/10/2016 08:58 pm
Rough numbers but you get the idea;

What's F9's payload capacity to GTO?  10,000 pounds?
What's the weight of the payload fairing?  5,000 pounds?
What's the revised payload capacity if you take the payload fairing along for the whole ride?  ?5000? pounds.

Substitute in actual numbers and you get actually poor numbers.  Weight carried on the first stage is not good.  Weight carried on the second stage is really not good.

Not actual numbers but IIRC the quoted formula was something like order of the 30% penalty for first stage reusability to payload was closer to one-to-one for the second stage, which would include keeping the fairing. The fairing is jettisoned when it is specifically because the mass is enough to impact the payload mass to orbit.

It's been touched on but not addressed specifically as far as I've seen but adding ANY mass to the fairing would also change the separation dynamics. Enough so you'd have to test the whole system again to ensure clean separation from the payload which is your MAIN (and that includes anything about reusability) metric. If they added piping and a thruster, (and really it would be at least four nozzles for proper control) and control and regulator equipment you've off-balanced the system and voided any previous testing results.

Randy
Title: Re: Fairing reuse
Post by: Chris Bergin on 03/10/2016 09:04 pm
I'll add my "update" on this after asking around. SpaceX has not commented on it, but a few sources (not SpaceXers it's worth adding) note it was an ACS experiment as part of fairing recovery evaluations.

For it to become official, SpaceX needs to say something and that would likely be either Elon tweeting or Gywnne mentioning it at a conference....but there you go from my chair.

For the interim this can be a fun thread where you talented folks can work the imagery, as we saw with this cool gifs:
http://forum.nasaspaceflight.com/index.php?topic=37727.msg1500634#msg1500634
Title: Re: Fairing reuse
Post by: symbios on 03/11/2016 07:23 pm
New image on Facebook.

Anyone recognises the logo in the fairing in the background back right.
Title: Re: Fairing reuse
Post by: ugordan on 03/11/2016 07:35 pm
Eutelsat?

FH booster nosecone as well.
Title: Re: Fairing reuse
Post by: Retired Downrange on 03/11/2016 08:08 pm
Any guesses about what the white curved structure barely visible in the extreme lower right of the photo might be? If it is not part of the building, it certainly is of a much larger diameter that anything else in the photo.
Title: Re: Fairing reuse
Post by: Kabloona on 03/11/2016 09:40 pm
Eutelsat?

Probably for Eutelsat's Satmex 9, which is up next after CRS-8.
Title: Re: Fairing reuse
Post by: pippin on 03/11/2016 09:55 pm

Any guesses about what the white curved structure barely visible in the extreme lower right of the photo might be? If it is not part of the building, it certainly is of a much larger diameter that anything else in the photo.
Oven to bake composite structures?
Title: Re: Fairing reuse
Post by: OxCartMark on 03/11/2016 10:46 pm
Nice pic.  Thanks.  I'm not convinced that the round thing is significantly larger in diameter but maybe it is larger in which case an autoclave makes sense.  Perhaps they chose the interesting route of making their own cylindrical housing with friction stir welding.  Say, what's that robot arm process going on under the unpainted fairing half in the foreground?
Title: Re: Fairing reuse
Post by: Robotbeat on 03/12/2016 12:39 am
Autoclaves definitely don't look like that.
Title: Re: Fairing reuse
Post by: Lee Jay on 03/12/2016 12:45 am
Autoclaves definitely don't look like that.

Yeah...they look a lot like a submarine with one end that opens.
Title: Re: Fairing reuse
Post by: Robotbeat on 03/12/2016 12:47 am
And they're made out of thick steel. That thing looks like it's made out of aerospace materials like aluminum or carbon fiber.
Title: Re: Fairing reuse
Post by: Lee Jay on 03/12/2016 12:53 am
Yeah...like a submarine!

(https://upload.wikimedia.org/wikipedia/en/4/47/Industrial_Autoclaves.jpg)
Title: Re: Fairing reuse
Post by: Lee Jay on 03/12/2016 12:59 am
Do they autoclave their fairings?  That would be a huge autoclave.
Title: Re: Fairing reuse
Post by: virnin on 03/12/2016 01:08 am
Any guesses about what the white curved structure barely visible in the extreme lower right of the photo might be? If it is not part of the building, it certainly is of a much larger diameter that anything else in the photo.

It's too blurry to be sure but it looks like there is a removable port near the base like you would see in a boiler or a storage tank that had to be periodically cleaned.
Title: Re: Fairing reuse
Post by: Burninate on 03/12/2016 01:46 am
Wild-ass guesses corroborated by nothing whatsoever:

The observed thrust is venting of the remaining pressure in an N2 pneumatic tank normally used in separation, associated with some safety procedure they're testing for Falcon Heavy, which will drop fairings (or perhaps interstage?) on a trajectory much closer to the launchsite in order to optimize RTLS.  They want the chance of ballistically dropping pressurized cylinders near population to be closer to zero than it is at present.

The cylinder is either a finished fairing at an angle, or a fairing spray/cure booth.  As mentioned upthread, fairings are delivered from overseas rather than manufactured in-house, but the center of the picture indicates they may not be painted when they get here.  Alternately, it's possible that it's an interstage or a stage that's simply suffering from some flavor of perspective distortion.
Title: Re: Fairing reuse
Post by: Robotbeat on 03/12/2016 01:57 am
Wild-ass guesses corroborated by nothing whatsoever:

The observed thrust is venting of the remaining pressure in an N2 pneumatic tank normally used in separation, associated with some safety procedure they're testing for Falcon Heavy, which will drop fairings (or perhaps interstage?) on a trajectory much closer to the launchsite in order to optimize RTLS.  They want the chance of ballistically dropping pressurized cylinders near population to be closer to zero than it is at present.

The cylinder is either a finished fairing at an angle, or a fairing spray/cure booth.  As mentioned upthread, fairings are delivered from overseas rather than manufactured in-house, but the center of the picture indicates they may not be painted when they get here.  Alternately, it's possible that it's an interstage or a stage that's simply suffering from some flavor of perspective distortion.
They make fairings in-house. Do you have a source for your statement that they aren't?
Title: Re: Fairing reuse
Post by: Burninate on 03/12/2016 02:03 am
Wild-ass guesses corroborated by nothing whatsoever:

The observed thrust is venting of the remaining pressure in an N2 pneumatic tank normally used in separation, associated with some safety procedure they're testing for Falcon Heavy, which will drop fairings (or perhaps interstage?) on a trajectory much closer to the launchsite in order to optimize RTLS.  They want the chance of ballistically dropping pressurized cylinders near population to be closer to zero than it is at present.

The cylinder is either a finished fairing at an angle, or a fairing spray/cure booth.  As mentioned upthread, fairings are delivered from overseas rather than manufactured in-house, but the center of the picture indicates they may not be painted when they get here.  Alternately, it's possible that it's an interstage or a stage that's simply suffering from some flavor of perspective distortion.
They make fairings in-house. Do you have a source for your statement that they aren't?

My mistake, I misread something a few pages back.
Title: Re: Fairing reuse
Post by: sewebster on 03/12/2016 04:28 am
Do they autoclave their fairings?  That would be a huge autoclave.

I assume they do? Aerospace autoclaves are rather large... Dreamliner autoclave is 9 m dia, 30 m long.
Title: Re: Fairing reuse
Post by: kkellogg on 03/13/2016 11:48 pm
Any guesses about what the white curved structure barely visible in the extreme lower right of the photo might be? If it is not part of the building, it certainly is of a much larger diameter that anything else in the photo.

I think it's a tank section for either F9 or FH.
Title: Re: Fairing reuse
Post by: CraigLieb on 03/14/2016 02:49 am
Any guesses about what the white curved structure barely visible in the extreme lower right of the photo might be? If it is not part of the building, it certainly is of a much larger diameter that anything else in the photo.

I think it's a tank section for either F9 or FH.

I looked through as many of the building tour videos and pictures as I could find and didn't
See that in any of them.
Title: Re: Fairing reuse
Post by: dorkmo on 03/14/2016 03:01 am
Any guesses about what the white curved structure barely visible in the extreme lower right of the photo might be? If it is not part of the building, it certainly is of a much larger diameter that anything else in the photo.

I think it's a tank section for either F9 or FH.

I looked through as many of the building tour videos and pictures as I could find and didn't
See that in any of them.

to me it looks like an interstage that has wiring on its exterior. what can be seen at the base looks like the holes for gridfins. not completely painted there. exterior wiring is a bit perplexing but makes me think its for a test flight which might mean heavy demo?
Title: Re: Fairing reuse
Post by: iamlucky13 on 03/14/2016 07:31 pm
Separation is done with pushers

I've always known it was done with pushers and I think N gas pushers but I'm surprised by the technology path they've chosen. I always assumed that they used COTS nitrogen gas springs of the type used in automotive lift gates or the type used in stamping dies.  In my scenario the halves would be held together with electrically releasable latches such as on car trunks.  I guess those assumptions show the field that I've been working in.  But also now see that if they'd have chosen the path that I envision there'd be challenges in bringing the fairing halves together evenly against the multiple springs.

Using a depressurized actuator, separate pressure reservoir, and a control valve can allow you to withdraw the latch pin without the push loads already on the fairing trying to bind up the latches.

The assembly problem of your idea can be avoided, however, by designing room for a retainer to hold the spring compressed in the right position until the latches are closed. Forgetting to do this with high force springs is huge pain the rear. Been there, done that, fortunately did not lose any fingers.
Title: Re: Fairing reuse
Post by: CyndyC on 03/15/2016 01:09 am
(http://public.cyndyclayton.fastmail.us/Flight/Rocket%20Fairing%20Closed%20139w.png)          (http://public.cyndyclayton.fastmail.us/Flight/Rocket%20Fairing%20Open%20200w.png)
Title: Re: Fairing reuse
Post by: meekGee on 03/15/2016 01:56 am
(http://public.cyndyclayton.fastmail.us/Flight/Rocket%20Fairing%20Closed%20200w.png)          (http://public.cyndyclayton.fastmail.us/Flight/Rocket%20Fairing%20Open%20200w.png)

An odd patent... (Low shock separation joint - US 7127994 B2)

Most of the spec is about a separation joint - nothing to do with a retained split fairing design...

Then there are these two figures at the end, seemingly out of the blue, a bit of text, and no claims related to this mechanism.

Sometimes you add text to prove the utility of the patent, but this doesn't look like it at all...

head scratch...

(And I doubt anyone can patent the idea of a retained split fairing anyway...  )
Title: Re: Fairing reuse
Post by: CyndyC on 03/15/2016 02:11 am
An odd patent... (Low shock separation joint - US 7127994 B2)

Most of the spec is about a separation joint - nothing to do with a retained split fairing design...

Then there are these two figures at the end, seemingly out of the blue, a bit of text, and no claims related to this mechanism.

Sometimes you add text to prove the utility of the patent, but this doesn't look like it at all...

head scratch...

(And I doubt anyone can patent the idea of a retained split fairing anyway...  )

Wow, how were you able to find the name and number? I came across it for a Biomimicry class assignment, and it seemed to fit the discussion here in a few & funny ways. Your doubts are not surprising since the patent has lapsed.
Title: Re: Fairing reuse
Post by: meekGee on 03/15/2016 03:13 am
An odd patent... (Low shock separation joint - US 7127994 B2)

Most of the spec is about a separation joint - nothing to do with a retained split fairing design...

Then there are these two figures at the end, seemingly out of the blue, a bit of text, and no claims related to this mechanism.

Sometimes you add text to prove the utility of the patent, but this doesn't look like it at all...

head scratch...

(And I doubt anyone can patent the idea of a retained split fairing anyway...  )

Wow, how were you able to find the name and number? I came across it for a Biomimicry class assignment, and it seemed to fit the discussion here in a few & funny ways. Your doubts are not surprising since the patent has lapsed.

Google Image Search, click the camera, then can search by URL...  If using chrome, there's a direct right-click short cut.

The amount of riddles this has solved for me...
Title: Re: Fairing reuse
Post by: wannamoonbase on 03/18/2016 02:47 pm
Anyone hazard a guess on how well retrieval would work during night launches?
Title: Re: Fairing reuse
Post by: Jarnis on 03/18/2016 03:50 pm
Anyone hazard a guess on how well retrieval would work during night launches?

Night vision goggles are fairly mature tech, as is flying in darkness with them.
Title: Re: Fairing reuse
Post by: Rabidpanda on 03/19/2016 08:59 am

Do they autoclave their fairings?  That would be a huge autoclave.

I assume they do? Aerospace autoclaves are rather large... Dreamliner autoclave is 9 m dia, 30 m long.

The fairings are cured in an oven, not an autoclave.
Title: Re: Fairing reuse
Post by: sewebster on 03/20/2016 05:33 pm

Do they autoclave their fairings?  That would be a huge autoclave.

I assume they do? Aerospace autoclaves are rather large... Dreamliner autoclave is 9 m dia, 30 m long.

The fairings are cured in an oven, not an autoclave.

Thanks. Do you know how they apply pressure to the parts?
Title: Re: Fairing reuse
Post by: Robotbeat on 03/20/2016 06:11 pm

Do they autoclave their fairings?  That would be a huge autoclave.

I assume they do? Aerospace autoclaves are rather large... Dreamliner autoclave is 9 m dia, 30 m long.

The fairings are cured in an oven, not an autoclave.

Thanks. Do you know how they apply pressure to the parts?
Perhaps they vacuum bag them?
Title: Re: Fairing reuse
Post by: sewebster on 03/20/2016 08:39 pm
The fairings are cured in an oven, not an autoclave.

Thanks. Do you know how they apply pressure to the parts?
Perhaps they vacuum bag them?

Yes, seems likely, but autoclaves are used in addition to vacuum to apply more pressure to reduce voids etc. Vacuum can only give you one atmosphere. There are other techniques for applying more pressure that don't involve an autoclave... https://en.wikipedia.org/wiki/Out_of_autoclave_composite_manufacturing
Title: Re: Fairing reuse
Post by: Rabidpanda on 03/21/2016 03:45 am


Do they autoclave their fairings?  That would be a huge autoclave.

I assume they do? Aerospace autoclaves are rather large... Dreamliner autoclave is 9 m dia, 30 m long.

The fairings are cured in an oven, not an autoclave.

Thanks. Do you know how they apply pressure to the parts?
Perhaps they vacuum bag them?

Yes, they are vacuum bagged.
Title: Re: Fairing reuse
Post by: Stan-1967 on 03/21/2016 04:04 am
Rough numbers but you get the idea;

What's F9's payload capacity to GTO?  10,000 pounds?
What's the weight of the payload fairing?  5,000 pounds?
What's the revised payload capacity if you take the payload fairing along for the whole ride?  ?5000? pounds.

Substitute in actual numbers and you get actually poor numbers.  Weight carried on the first stage is not good.  Weight carried on the second stage is really not good.

Very poor numbers indeed.  Recall the Taurus XL vehicle that failed to jettison the fairing on the launch of the "Orbiting Carbon Observatory", and "Glory".  In both cases the vehicle failed to reach orbit.   
Title: Re: Fairing reuse
Post by: Stan-1967 on 03/21/2016 04:47 am
(http://public.cyndyclayton.fastmail.us/Flight/Rocket%20Fairing%20Closed%20139w.png)          (http://public.cyndyclayton.fastmail.us/Flight/Rocket%20Fairing%20Open%20200w.png)

Why not develop a fairing that peels back like a banana peel and locks against the second stage skin? Kind of like the legs, but in reverse.

It could be used as a TPS for the second stage so the stage can be recovered.

No need to peel it back if it is taken to orbit.  It could be opened right before spacecraft deployment.  But the fairing would reduce payload mass.

1.  Is there substantial advantage to recovering a fairing like in the schematic above as a single assembly, vs. trying to recover two individual halves?   The aerodynamics of the fairing re-joined together seem more suited to surviving & conducting a controlled reentry. 

2.  The fact that F9 fairings have been recovered, either in pieces or near complete halves, show that they are strong enough to withstand reentry.  However I don't see that the "halves" are going to be controllable during descent, which makes the condition they survive in questionable.

3.   If the springs in the schematic were mounted on the outside of that "interstage" looking attachment hoop instead of the inside, they could still be used to open up the hinged fairing.   (encasing the springs in an aeroshell/fairing of sorts)   If the mounting hoop that the fairing halves are hinged to has a larger inner diameter than the outer diameter of the second/final stage, you could slide the entire opened up fairing & mounting hoop down the side of the stage and jettison it at the rear of the rocket, into the plume of the accelerating stage.  It would have to have clearance of the payload pedestal & payloads, as well as any exterior plumbing on the side of the rocket.

4.  After the fairing halves & mounting hoop has slid down the length of the accelerating rocket, & is clear of the engine nozzles & associated gas plume,  you could close and lock the halves and have a very aerodynamic shape for controlled reentry and recovery.
Title: Re: Fairing reuse
Post by: Jim on 03/21/2016 02:52 pm


2.  The fact that F9 fairings have been recovered, either in pieces or near complete halves, show that they are strong enough to withstand reentry.

It was pieces, which is standard for all fairings and not just F9.  Most just sink.  It has nothing to with strength or withstanding.
Title: Re: Fairing reuse
Post by: cambrianera on 03/21/2016 07:09 pm

If the mounting hoop that the fairing halves are hinged to has a larger inner diameter than the outer diameter of the second/final stage, you could slide the entire opened up fairing & mounting hoop down the side of the stage and jettison it at the rear of the rocket, into the plume of the accelerating stage.  It would have to have clearance of the payload pedestal & payloads, as well as any exterior plumbing on the side of the rocket.


You don't need a full clamshell opening to slide your fairing back.
And making the cylindrical part of the fairing in a single piece, without joints, you can save a good amount of mass.
"Small" problem: sliding the fairing into the plume of the accelerating stage you are likely going to shred it in pieces smaller than those previously recovered.
I did this animation to look at the concept some month ago, then I realized the "small" problem .
Title: Re: Fairing reuse
Post by: Stan-1967 on 03/21/2016 11:19 pm

If the mounting hoop that the fairing halves are hinged to has a larger inner diameter than the outer diameter of the second/final stage, you could slide the entire opened up fairing & mounting hoop down the side of the stage and jettison it at the rear of the rocket, into the plume of the accelerating stage.  It would have to have clearance of the payload pedestal & payloads, as well as any exterior plumbing on the side of the rocket.


You don't need a full clamshell opening to slide your fairing back.
And making the cylindrical part of the fairing in a single piece, without joints, you can save a good amount of mass.
"Small" problem: sliding the fairing into the plume of the accelerating stage you are likely going to shred it in pieces smaller than those previously recovered.
I did this animation to look at the concept some month ago, then I realized the "small" problem .

Nice animation!  Captures the concept exactly.  I wonder if the "small" problem of the exhaust plume could be avoided if the rocket flew a more highly lofted trajectory and jettison the fairing right after MECO and before second stage ignition, using smaller ullage rockets?  Alternately throttle down the S2 engine as far as possible during jettison.   My first thoughts was that the potential to tear apart the fairing would look like the Saturn V second stage interstage in this clip.  ( it survived a bit scorched apparently )

https://www.youtube.com/watch?v=HTGk3UM-IOU#t=4m23s

Title: Re: Fairing reuse
Post by: Chris_Pi on 03/22/2016 02:00 am
That Saturn interstage started to tumble pretty quick. I think having the engine running at all when the longer Falcon fairing drops down the whole length of the second stage might be a problem. Jettisoning or folding out the rear bevel on the fairing would increase the clearance quite a bit but it still has to come off very straight and preferably fast so the second stage can get started.

More than a few degrees rotation during separation and the fairing starts bumping into important parts. It could probably work but fairing separation would definitely not be boring for a while. :-\ More like a second really long interstage.
Title: Re: Fairing reuse
Post by: dorkmo on 03/22/2016 02:31 am
im not really following, but for an idea, perhaps following seperation using thrusters the two halves could quickly dock with one another to become one again.
Title: Re: Fairing reuse
Post by: hrissan on 03/22/2016 10:12 am
Might the future fairing be attached to the first stage and return together with it?
Title: Re: Fairing reuse
Post by: rpapo on 03/22/2016 10:51 am
Might the future fairing be attached to the first stage and return together with it?
To do that, it would probably have to (1) cover the entire second stage, (2) be able to open very quickly at staging time and (3) survive the starting of the second stage motors.

If it could do all that, and close on its own, then it would probably help the aerodynamics of stage return by pushing the center of drag even higher on the stage.  That said, that would reduce the effectiveness of the grid fins unless they were moved even higher than they already are.
Title: Re: Fairing reuse
Post by: cambrianera on 03/22/2016 10:59 am
@Stan:
Sliding the fairing before MECO you can lock it on the upper part of the interstage, and get a free ride back to earth (what hrissan wrote): I remember Jim said spacecrafts need protection also after MECO, therefore this should be carefully balanced.
Throttling down second stage engine to minimum during sliding may be ok (but not a given).
@Chris:
A sliding fairing should have rails, therefore a straighter path & no lateral jerks on separation.
@dorkmo:
This means add to them complete navigation & RCS....
Title: Re: Fairing reuse
Post by: Stan-1967 on 03/23/2016 02:53 pm
@Stan:
Sliding the fairing before MECO you can lock it on the upper part of the interstage, and get a free ride back to earth (what hrissan wrote): I remember Jim said spacecrafts need protection also after MECO, therefore this should be carefully balanced.
Throttling down second stage engine to minimum during sliding may be ok (but not a given).
@Chris:
A sliding fairing should have rails, therefore a straighter path & no lateral jerks on separation.
@dorkmo:
This means add to them complete navigation & RCS....

I like the idea of sliding the fairing all the way onto S1 for the return ride, but I think this concept would then be limited to rockets with a S1 that delivers S2 & payload at very high altitudes where the exposed payload would not be damaged.  In reading the SpaceX F9 users manual, fairing jettison is predicated on the dyanamic pressure on the fairing falling to a specified amount.   The vehicle does not reach this until well into the burn of S2 and the rocket is only around 50km up at MECO. ( hence the lofted trajectory idea )   

The Atlas V S1 on the other hand, is likely around 100km high at MECO.  I would note that the Atlas V sequence after MECO is to start S2 and immediately jettison the fairing once S2 thrust is nominal.   The Atlas V vehicle has other problems with this concept that make it less interesting to consider.   The concept of the sliding fairing might work on the FH center core, since it will be throttled down and have a longer burn time, plus the side cores will be giving extra push to get it to a high altitude at center core MECO.   

I agree that some type of rail, plus bearings, would be needed to guide the fairing as it slides.   A stuck fairing in the wrong position would be loss of mission for the rocket.
Title: Re: Fairing reuse
Post by: Stan-1967 on 03/23/2016 03:01 pm
im not really following, but for an idea, perhaps following seperation using thrusters the two halves could quickly dock with one another to become one again.

Watch the animation from cambrianera in reply#200.   How would separate halves autonomously dock after jettison?  You will need more than thrusters. You would need to install a separate docking mechanisms, avionics & special software, laser/radar rangefinding gear?  I think it would be a long list of very complicated stuff. 

Title: Re: Fairing reuse
Post by: spacenut on 03/23/2016 03:48 pm
Fairing could also be attached to the second stage to protect the engine during reentry if and when a second stage is reused. 

Title: Re: Fairing reuse
Post by: Comga on 03/23/2016 05:26 pm
[sarcasm]They could just have Scotty beam them back to the HIF.[/sarcasm]

If fairings are not ejected, their mass takes away from the payload, possibly driving it negative.
We have seen payloads launched into "hydrosynchronous orbits" when fairings don't eject.

SpaceX is staging earlier than optimum to recover the first stage.  They are not going to stage later than optimum to be out of the atmosphere and try to include the fairing in the first stage recovery. edit: IMO

Fairing halves will stay separate once separated.  As Stan-1967 said, rejoining would be of overwhelming complexity.

How about we not come up with more Rube Goldberg systems and wait to see what SpaceX actually does?
Title: Re: Fairing reuse
Post by: Lar on 03/23/2016 06:01 pm
We tried the second stage as ship with cargo bay thing... didn't work that well... all of these fairing slides up and down ideas smack of that.

I agree with Comga, rather than doing what-if, why not try to figure out what SpaceX is doing and why and what things they are going to try next.  Some of the best threads on the site are those kind (the barge threads in many cases are like that)
Title: Re: Fairing reuse
Post by: sevenperforce on 03/23/2016 07:59 pm
Last I heard, FH will use FT side boosters but a v1.1 core. So SpaceX isn't averse to retaining multiple versions of the same stage for different purposes.

To that end, might SpaceX consider two versions of the upper stage -- one that is expendable with the current breakaway fairing, and one that is reusable with a clamshell PICA-X-covered fairing that opens around 30 degrees to release the payload, then locks? It's a payload cut, but it might be worthwhile for lower-mass payloads to LEO.

With the fairing locked out at 30 degrees, the upper stage would passively orient into a retrograde attitude, and the PICA-X layer on the locked fairing would absorb the brunt of the compressive heating. It would also result in a significantly lower terminal velocity, which is good for landing. Higher center of gravity, though, which is less good for landing.
Title: Re: Fairing reuse
Post by: Lar on 03/23/2016 08:50 pm
Last I heard, FH will use FT side boosters but a v1.1 core. So SpaceX isn't averse to retaining multiple versions of the same stage for different purposes.

Do you have a cite for that.. I doubt they are building v1.1 cores any more.

As to the rest, I think it much more interesting to try to figure out what SpaceX actually are up to near term. But that's just me.
Title: Re: Fairing reuse
Post by: spacenut on 03/23/2016 08:59 pm
Sorry, when I posted, I was thinking about the interstage between first and second stage, not the nose fairing.  What is wrong with dumping the fairings?  You can't save everything yet. 
Title: Re: Fairing reuse
Post by: sevenperforce on 03/23/2016 09:01 pm
Sorry, when I posted, I was thinking about the interstage between first and second stage, not the nose fairing.  What is wrong with dumping the fairings?  You can't save everything yet.
The fairings are hella expensive.
Title: Re: Fairing reuse
Post by: robert_d on 03/23/2016 09:05 pm
Has anyone considered going the other way with the Faring? By that I mean make it super cheap like the wrapping on a candy bar? I know there are aerodynamic loads and all that but just wondering if a dry nitrogen pressurized gas bag made out of some tough material could be used. After all NASA is investigating inflatables for potential reentry use, so maybe not so crazy? Just wondering.
Title: Re: Fairing reuse
Post by: mme on 03/23/2016 09:32 pm
Sorry, when I posted, I was thinking about the interstage between first and second stage, not the nose fairing.  What is wrong with dumping the fairings?  You can't save everything yet.
The fairings are hella expensive.
My understanding is that they take a long time to make, are big to store and it's hard to ramp up production.
Title: Re: Fairing reuse
Post by: Jim on 03/23/2016 09:38 pm
Has anyone considered going the other way with the Faring? By that I mean make it super cheap like the wrapping on a candy bar? I know there are aerodynamic loads and all that but just wondering if a dry nitrogen pressurized gas bag made out of some tough material could be used. After all NASA is investigating inflatables for potential reentry use, so maybe not so crazy? Just wondering.

there is a thread on this and reasons that it is not feasible.
Title: Re: Fairing reuse
Post by: Stan-1967 on 03/24/2016 03:42 am
Has anyone considered going the other way with the Faring? By that I mean make it super cheap like the wrapping on a candy bar? I know there are aerodynamic loads and all that but just wondering if a dry nitrogen pressurized gas bag made out of some tough material could be used. After all NASA is investigating inflatables for potential reentry use, so maybe not so crazy? Just wondering.

It's not just aero loads.   The fairing shroud also provides an acoustic, thermal, chemical, & EMI environment that keeps the payload safe while waiting for launch as well as during ascent to orbit.  No cheap bag of gas is going to work for all those requirements.


 

Title: Re: Fairing reuse
Post by: HMXHMX on 03/24/2016 03:55 am
Has anyone considered going the other way with the Faring? By that I mean make it super cheap like the wrapping on a candy bar? I know there are aerodynamic loads and all that but just wondering if a dry nitrogen pressurized gas bag made out of some tough material could be used. After all NASA is investigating inflatables for potential reentry use, so maybe not so crazy? Just wondering.

It's not just aero loads.   The fairing shroud also provides an acoustic, thermal, chemical, & EMI environment that keeps the payload safe while waiting for launch as well as during ascent to orbit.  No cheap bag of gas is going to work for all those requirements.



Apropos of that:  http://www.parabolicarc.com/2016/03/21/paragon-wins-nasa-sbir-phase-ii-contract-improved-inspace-transportation/#more-57831
Title: Re: Fairing reuse
Post by: dorkmo on 03/24/2016 04:23 am
Fairing halves will stay separate once separated.  As Stan-1967 said, rejoining would be of overwhelming complexity.

i think you could potentially be trading one complex problem for a slightly less complex problem.

in a hypothetical world where joining the halves makes rentry significantly more survivable, i think youd want to consider it.

edit: and to satisfy the calls for realism. the new thrusters could enable a rejoining operation. plus they make a lot of docking hardware/software for dragon already.
Title: Re: Fairing reuse
Post by: robert_d on 03/24/2016 01:52 pm
Has anyone considered going the other way with the Faring? By that I mean make it super cheap like the wrapping on a candy bar? I know there are aerodynamic loads and all that but just wondering if a dry nitrogen pressurized gas bag made out of some tough material could be used. After all NASA is investigating inflatables for potential reentry use, so maybe not so crazy? Just wondering.

there is a thread on this and reasons that it is not feasible.
OK. Sorry, didn't realize there was another thread. At least the downthread comment by HMXHMX shows people are trying different concepts. Even I know that most of what is proposed here would be unworkable due to weight and complexity.

I would think they would start simple to see what could be done with the current fairing. What could stabilize it in at least one dimension for some period of time? Maybe add a small reel of ribbon to each half near the base and unreel it after separation. Like a kite tail. See if it will stabilize in pitch and maybe a bit in yaw. See how long the ribbon survives. Then if that gets anywhere, add a few deployable tabs that would autonomously adjust for roll. If those don't help, it seems that a far larger (he he he - Falcon 2 core) first stage would be required to have a much more massive system in place. Too complex and expensive.


 
Title: Re: Fairing reuse
Post by: sevenperforce on 03/24/2016 02:35 pm
I think you could potentially be trading one complex problem for a slightly less complex problem.

in a hypothetical world where joining the halves makes rentry significantly more survivable, i think youd want to consider it.

edit: and to satisfy the calls for realism. the new thrusters could enable a rejoining operation. plus they make a lot of docking hardware/software for dragon already.
All the active docking on Dragon V2 depends on the androgynous docking port. Not going to work in free-fall.

For second-stage reuse on lower-velocity missions with bulky payload requiring the fairing, the two fairing halves could be hinged, with struts connecting them to the landing legs. The fairing could be made more lightweight because the same opening mechanism is used for two different things. The landing legs would lock into place, maintaining the fairing halves firmly in a 30-degree open configuration. The two halves would thus feather like the hinged wings on SpaceShipOne, producing tremendous drag and distributing the heat flux very efficiently.

I attached a diagram to show how the overall sequence could work.

There are several major advantages. Rather than making the fairings sturdier to survive independent re-entry, the fairings can actually be made even lighter because they don't leave the vehicle. The heat redistribution is excellent and terminal velocity is much lower, placing less stress on the vehicle and requiring less dV. Recovery is in one piece and doesn't require retrieval of three different objects. Perhaps most importantly, this design means that the entire second stage can do a tiny burn at apogee and complete an entire orbit, then re-enter west of launch for a controlled RTLS landing. Finally, the greater weight of the fairing is a huge advantage with a suicide burn, as the T/W ratio is significantly lower.
Title: Re: Fairing reuse
Post by: Jim on 03/24/2016 02:55 pm
the fairings can actually be made even lighter because they don't leave the vehicle.

Can't say that.   Keeping them open and the landing loads would likely make them heavier than stand alone.
Title: Re: Fairing reuse
Post by: sevenperforce on 03/24/2016 03:26 pm
the fairings can actually be made even lighter because they don't leave the vehicle.

Can't say that.   Keeping them open and the landing loads would likely make them heavier than stand alone.
They aren't support structures.

Easier (from a weight basis) than making them reusable independently.
Title: Re: Fairing reuse
Post by: Jim on 03/24/2016 03:48 pm

They aren't support structures.

Easier (from a weight basis) than making them reusable independently.

Again, you have no data to support your claim.  All that might be needed to support independent reusability (as in standalone) is an attitude control system and parachute. 

Supporting the fairing on the stage partially open for entry and landing will require major reinforcement of the fairing.
Title: Re: Fairing reuse
Post by: sevenperforce on 03/24/2016 04:11 pm

They aren't support structures.

Easier (from a weight basis) than making them reusable independently.

Again, you have no data to support your claim.  All that might be needed to support independent reusability (as in standalone) is an attitude control system and parachute. 

Supporting the fairing on the stage partially open for entry and landing will require major reinforcement of the fairing.
Parachutes are heavy.

The reinforcement would primarily be needed for the landing legs, but they already need to be really strong.

Sure, I'm making educated guesses here, but it would be worth investigation.
Title: Re: Fairing reuse
Post by: RanulfC on 03/24/2016 04:12 pm
You're assuming a very narrow, and highly limited criteria for the concept;
"For second-stage reuse on lower-velocity missions with bulky payload requiring the fairing"

And the fairing would require structural additions to stand the heating and aero-loading of being attached to the seconds stage in a high-drag configuration. "Easier" than being reusable independently will not automatically translate to saving in weight. Your heat loading is going to be greater on the deployed legs AND you will have added aerodynamic problems with that configuration. (There are very good reasons why no one suggests deploying landing legs prior to reentry)

I'd actually question the idea of fairing reuse on an operational and economic basis because it only makes sense in either case if doing so costs (operationally AND financially) as close as possible to nothing beyond current costs. Trying to make everything on the F9 system "reusable" is gong to end up being self-defeating as the LV system is only an interim vehicle anyway. The architecture can only go so far before it runs into engineered in issues that limit it. (You lose the payload/upper-stage, and probably the vehicle in any abort/incident once its off the pad. Dragon/Dragon-2 are the only exceptions because any attempt at a similar LES abort system for unmanned payload will significantly detract from the payload itself)

Once you move to making the entire second stage reusable (and all that implies which includes things like fully INTACT abort modes for payload recovery during ALL aspects of flight, which is tough even when you START with a 'reusable' design and not a expendable one) you move sharply away from an interim vehicle and have to make significant modifications (as we've seen in these discussions) costing time, effort and money that directly subtracts from other programs.

If Elon and SpaceX are as focused on Mars as they seem to be then there is a point very close to where we are now where "good enough" is as far as you want to go with the Falcon-9 family, and instead focus on the next generation vehicle design which will be reusable from the start.

Randy
Title: Re: Fairing reuse
Post by: Jim on 03/24/2016 04:21 pm

Parachutes are heavy.

The reinforcement would primarily be needed for the landing legs, but they already need to be really strong.

More  (and heavy) reinforcements are needed for the fairing to handle to the additional loads that I list.
Title: Re: Fairing reuse
Post by: sevenperforce on 03/24/2016 06:00 pm
If they can allow for an additional SECO event, then what about having the fairing hinged at the nose? They could SECO, unhinge the thing and push it away with RCS, then restart the engine. It could then close on its own (or not, if re-entry characteristics were better).
Title: Re: Fairing reuse
Post by: robert_d on 03/25/2016 02:03 am
Does anyone think it would be worth the cost of a bottom up test program as in dropping fairings with parachutes from airplanes to see if that end of things can be made to work? Seems to again lead to a lot of cost for questionable gains.
Title: Re: Fairing reuse
Post by: cscott on 03/25/2016 02:53 pm
SpaceX is already doing a test program, and its lift to altitude is free.  They get a test opportunity about once a month.  How can you beat that?
Title: Re: Fairing reuse
Post by: sevenperforce on 03/25/2016 03:19 pm
You know, if it would be possible to hinge the damn thing, why not simply hinge it along one long edge? Then it could open along that edge and tumble away still connected.
Title: Re: Fairing reuse
Post by: JasonAW3 on 03/25/2016 03:48 pm
You know, if it would be possible to hinge the damn thing, why not simply hinge it along one long edge? Then it could open along that edge and tumble away still connected.

Aerodynamics, while minimal at the altitudes that fairings are generally dropped from, would likely either bounce the fairing pairs back into the rocket, or simply tear them apart at the hinge.
Title: Re: Fairing reuse
Post by: JasonAW3 on 03/25/2016 03:53 pm

Parachutes are heavy.

The reinforcement would primarily be needed for the landing legs, but they already need to be really strong.

More  (and heavy) reinforcements are needed for the fairing to handle to the additional loads that I list.

What about an RCS system with a Ram-air Ballute?  Less issues with rigging and can be made fairly low mass.

     I'm not certain, but I think it might even be able to be made with a lower overall mass than a conventional parachute.
Title: Re: Fairing reuse
Post by: sevenperforce on 03/25/2016 04:56 pm
You know, if it would be possible to hinge the damn thing, why not simply hinge it along one long edge? Then it could open along that edge and tumble away still connected.

Aerodynamics, while minimal at the altitudes that fairings are generally dropped from, would likely either bounce the fairing pairs back into the rocket, or simply tear them apart at the hinge.
I thought the fairing was only jettisoned once it was far enough into space that there was no risk of harm to the payload from any aerodynamic effects.
Title: Re: Fairing reuse
Post by: cambrianera on 03/25/2016 05:42 pm
You know, if it would be possible to hinge the damn thing, why not simply hinge it along one long edge? Then it could open along that edge and tumble away still connected.
If you push a long edge hinged fairing over the other long edge, you get an inward movement of the hinge.
You can add a reaction beam to keep the hinge clear from the payload, but this would increase the mass of the fairing.
Title: Re: Fairing reuse
Post by: sevenperforce on 03/25/2016 11:41 pm
You know, if it would be possible to hinge the damn thing, why not simply hinge it along one long edge? Then it could open along that edge and tumble away still connected.
If you push a long edge hinged fairing over the other long edge, you get an inward movement of the hinge.
You can add a reaction beam to keep the hinge clear from the payload, but this would increase the mass of the fairing.
This is probably crazy, but what about manufacturing the fairing in three pieces rather than two: one the current size, then two 90-degree ones. Have the larger section hinge to both the other smaller sections so they open up like double doors.
Title: Re: Fairing reuse
Post by: NWade on 03/26/2016 07:16 am
C'mon folks, this is all a bit ridiculous.  ??? You're forgetting a major issue: MASS
 
If you keep the fairing attached to the second stage you are having to accelerate a lot more mass up to your final velocity - plus carry it around for any maneuvering and de-orbit burns. And on top of that, having it hinged open or cantilevered out means your center of thrust may no longer be going through your center of mass - have fun with that! All of these things are tremendously wasteful and makes all of your operations harder. The best thing to do is keep the fairings as light as possible and jettison them as early as possible. The slower the rocket is going when you ditch them, the lower your re-entry energy is going to be (coming in from slower or a lower altitude, or both).
 
The K.I.S.S. principle applies, always.
 
--Noel
 
Title: Re: Fairing reuse
Post by: sevenperforce on 03/26/2016 11:54 am
C'mon folks, this is all a bit ridiculous.  ??? You're forgetting a major issue: MASS
 
If you keep the fairing attached to the second stage you are having to accelerate a lot more mass up to your final velocity - plus carry it around for any maneuvering and de-orbit burns. And on top of that, having it hinged open or cantilevered out means your center of thrust may no longer be going through your center of mass - have fun with that! All of these things are tremendously wasteful and makes all of your operations harder. The best thing to do is keep the fairings as light as possible and jettison them as early as possible. The slower the rocket is going when you ditch them, the lower your re-entry energy is going to be (coming in from slower or a lower altitude, or both).
 
The suggestion of hingeing the fairing was to allow it to be jettisoned in one piece, not with the intent of carrying it to orbit.
Title: Re: Fairing reuse
Post by: Jim on 03/26/2016 01:07 pm
Hingeing would take too long to come off
Title: Re: Fairing reuse
Post by: OxCartMark on 03/27/2016 12:35 am
Before we get too deep into designing this (which I think began a dozen or so pages back) can someone provide some numbers for pitot static pressure at that altitude and speed?  Maybe then with that we can do some slightly more educated guessmongering.
Title: Re: Fairing reuse
Post by: Arb on 03/27/2016 02:03 pm
Before we get too deep into designing this (which I think began a dozen or so pages back) can someone provide some numbers for pitot static pressure at that altitude and speed?  Maybe then with that we can do some slightly more educated guessmongering.

And if this is going to become a design thread it should be so renamed and a separate updates thread created for any news (official or otherwise) about what SpaceX are really doing...

Mods, please.
Title: Re: Fairing reuse
Post by: rickyramjet on 03/27/2016 03:42 pm
Before we get too deep into designing this (which I think began a dozen or so pages back) can someone provide some numbers for pitot static pressure at that altitude and speed?  Maybe then with that we can do some slightly more educated guessmongering.

And if this is going to become a design thread it should be so renamed and a separate updates thread created for any news (official or otherwise) about what SpaceX are really doing...

Mods, please.
How is this thread any different than the hundreds of others where NSFers make design suggestions in the absence of info from SpaceX?  Or, even in the absence of scientific knowledge? I say leave it as is!
Title: Re: Fairing reuse
Post by: cscott on 03/27/2016 05:54 pm
For the same reason many other threads on this site are split into "update" and "discussion" threads---some of us have much less patience for rube goldberg guesswork or (on other threads) concern trolling than others.
Title: Re: Fairing reuse
Post by: iamlucky13 on 04/01/2016 02:01 am
You know, if it would be possible to hinge the damn thing, why not simply hinge it along one long edge? Then it could open along that edge and tumble away still connected.

That radically changes the separation dynamics, and not in a good way. As Orbital Sciences can attest, making a fairing separate reliably under thrust loads is not a trivial problem.

Sorry, when I posted, I was thinking about the interstage between first and second stage, not the nose fairing.  What is wrong with dumping the fairings?  You can't save everything yet.
The fairings are hella expensive.

I don't know if they're "hella" expensive, but they are significantly more expensive than I think most people realize. Apparently Ariane 5 fairings are around $6 million, and that's a similar size composite fairing. SpaceX might be doing theirs for cheaper, but even half that is still no small pile of pennies.
http://spacenews.com/41132ruag-books-order-for-18-ariane-5-fairings/

The fairing is certainly a lot less expensive than a first stage, but I suspect SpaceX is hoping it will prove one of the easiest parts to retrieve, so even if the value of the savings is not in the same ballpark as re-using a 1st stage, it might have a high return relative to the amount they have to invest developing the recovery technique.
Title: Re: Fairing reuse
Post by: JamesH65 on 04/01/2016 10:04 am
 It does beg the questions of WHY they are so expensive. Anyone know?
Title: Re: Fairing reuse
Post by: rpapo on 04/01/2016 10:14 am
It does beg the questions of WHY they are so expensive. Anyone know?
They're big, and they're composite.  The cost of making composite structures goes up rapidly with size, for a variety of reasons (material, tooling, processes required, difficulty in avoiding flaws, etc).
Title: Re: Fairing reuse
Post by: JamesH65 on 04/01/2016 01:24 pm
It does beg the questions of WHY they are so expensive. Anyone know?
They're big, and they're composite.  The cost of making composite structures goes up rapidly with size, for a variety of reasons (material, tooling, processes required, difficulty in avoiding flaws, etc).

Still, $6M seems a lot. Once you have the tooling in place, and have sorted the process and the QA, I would expect the price to drop fairly rapidly.
Title: Re: Fairing reuse
Post by: sevenperforce on 04/01/2016 02:26 pm
You know, if it would be possible to hinge the damn thing, why not simply hinge it along one long edge? Then it could open along that edge and tumble away still connected.

That radically changes the separation dynamics, and not in a good way. As Orbital Sciences can attest, making a fairing separate reliably under thrust loads is not a trivial problem.
What about something like this?

(http://s17.postimg.org/va7ysuhlr/fairing.png)

One seam, two hinges. Each hinge only needs 45 degrees of movement to provide full clearance; the imbalanced thrust loading immediately pulls the entire fairing off to the side opposite the seam. Spring-loading the hinges ought to provide a smooth enough and rapid enough deployment to clear the payload, and would be lighter than using a pneumatic system. You might need a puff of RCS to correct for the millisecond of imbalanced thrust on the rocket but given the mass of the rocket, fuel, and payload in comparison to the mass of the fairing the misalignment would be minuscule.

Assuming that the springs push the hinge into a locked position, the fairing would present a high surface area for re-entry and naturally align itself along an aerodynamic plane which protects the inside.
Title: Re: Fairing reuse
Post by: Jim on 04/01/2016 03:20 pm
1.  Spring-loading the hinges ought to provide a smooth enough and rapid enough deployment to clear the payload,

2. and would be lighter than using a pneumatic system.

3. You might need a puff of RCS to correct for the millisecond of imbalanced thrust on the rocket but given the mass of the rocket, fuel, and payload in comparison to the mass of the fairing the misalignment would be minuscule.


1.  What type of springs?  And how do you know they "ought" to?

2.  Based on what?  If no pneumatics, what pushes the fairing away?

3.  What RCS?

Do you know that the fairing separates while the vehicle is under thrust and still accelerating.

Also, the bottom of the fairing is disconnected at the same time as the seam splits.
Title: Re: Fairing reuse
Post by: Joffan on 04/01/2016 04:29 pm
Question - would it be possible to open the fairing between stage 1 MECO and stage 2 engine start, or is that still too low in the atmosphere for a typical payload? Would there be any issues with shedding the fairing either under no thrust or with the engine start-up thrust?

My expectation is that one of these issues is a deal-breaker for slightly earlier jettison of the fairing, but I don't know for sure...
Title: Re: Fairing reuse
Post by: Senex on 04/01/2016 04:47 pm
I just re-read the thread — leads me to the following points:

The fairing must be jettisoned.  Carrying the mass to orbit kills your payload capacity.  Not debatable.

The fairing has a large surface area and a low mass.  "Fluffy" recovery — less heating.  A whole different recovery mode from the second stage.  A paper airplane "dropped" from orbit will survive.  (See Japanese origami experiment - the problem is finding it!)

The shape of the half-fairings is a good approximation of a lifting body.  If you can organize the fairing's mass to put the centre of gravity in the right place it will "fly."  The trick may be initially stabilizing it in the correct attitude — which may be what SpaceX is working on.

They may be trying to figure out how much damage is from wave action.  Minor flotation bags and a beacon could help in recovering the fairing before it is damaged.

This should be doable — after some trial and error.  And they get a trial for "free" on every launch.
Title: Re: Fairing reuse
Post by: sevenperforce on 04/01/2016 05:35 pm
1.  Spring-loading the hinges ought to provide a smooth enough and rapid enough deployment to clear the payload,

2. and would be lighter than using a pneumatic system.

3. You might need a puff of RCS to correct for the millisecond of imbalanced thrust on the rocket but given the mass of the rocket, fuel, and payload in comparison to the mass of the fairing the misalignment would be minuscule.


1.  What type of springs?  And how do you know they "ought" to?

2.  Based on what?  If no pneumatics, what pushes the fairing away?

3.  What RCS?

Do you know that the fairing separates while the vehicle is under thrust and still accelerating.

Also, the bottom of the fairing is disconnected at the same time as the seam splits.
Outward-opening hinges mounted on the inside. Steel springs, I assume. I'm saying they could be designed to open smoothly and rapidly enough.

The fairing would be pushed away by the continued acceleration of the vehicle; as soon as the springs opened, the center of mass would shift and cause differential force on the fairing. You would need only one pneumatic clip holding the two doors together and fixed to the second stage body; once that clip retracts, the doors swing open and acceleration takes care of the rest.

I was talking about the RCS on the upper stage being used to correct the stage misalignment due to the momentary COM shift.
Title: Re: Fairing reuse
Post by: RDoc on 04/01/2016 05:46 pm
I just re-read the thread — leads me to the following points:

The fairing must be jettisoned.  Carrying the mass to orbit kills your payload capacity.  Not debatable.

The fairing has a large surface area and a low mass.  "Fluffy" recovery — less heating.  A whole different recovery mode from the second stage.  A paper airplane "dropped" from orbit will survive.  (See Japanese origami experiment - the problem is finding it!)

The shape of the half-fairings is a good approximation of a lifting body.  If you can organize the fairing's mass to put the centre of gravity in the right place it will "fly."  The trick may be initially stabilizing it in the correct attitude — which may be what SpaceX is working on.

They may be trying to figure out how much damage is from wave action.  Minor flotation bags and a beacon could help in recovering the fairing before it is damaged.

This should be doable — after some trial and error.  And they get a trial for "free" on every launch.

This is my view as well, but with the addition of some control surfaces and flight computers.
Title: Re: Fairing reuse
Post by: cambrianera on 04/01/2016 05:54 pm
@sevenperforce,
once your “doors“ open, the center of mass of the system follow the movement of the doors.
Moreover the doors are loosing their stand on the second stage.
The result is the fairing collapsing on the payload.
Title: Re: Fairing reuse
Post by: The Amazing Catstronaut on 04/01/2016 06:20 pm
You can reuse a fairing with a normal fairing separation, indeed, you should be. Fairings ain't broke and are a fairly rare failure mode if your quality assurance is indeed assured. It works, it's optimal, we should focus our attention on what the fairing is doing once detached from the structure of the rocket.

I've always been of the opinion giving the fairing a few thrusters to orient itself, a (light) parafoil, a GPS, and then scooting the the fairing out of the air SMART reuse/CORONA style is the right idea. You can do shebang without adding a ridiculous amount of mass, although you are going to have to accept a certain minor amount of performance loss.

I don't know if they're actually doing that. To me the idea seems sensible enough I have the feeling I've heard it somewhere before. Unsure. I didn't read the whole thread nor have I read too deeply into it.

Edit: And after looking back in the thread it seems that idea has been suggested before and I even replied to it. Doh!
Title: Re: Fairing reuse
Post by: sevenperforce on 04/01/2016 07:34 pm
@sevenperforce,
once your “doors“ open, the center of mass of the system follow the movement of the doors.
Moreover the doors are loosing their stand on the second stage.
The result is the fairing collapsing on the payload.
Then add a vertical bearing arm to the inside of the upper stage coupler to hold the fairing in place until the COM shifts far enough out.
Title: Re: Fairing reuse
Post by: Jim on 04/01/2016 09:09 pm

The fairing would be pushed away by the continued acceleration of the vehicle;

Fairings aren't pushed away by the vehicle.  They are detached at the base at the same time as the seams open and are pushed away by a pneumatic system or ordnance.

You would need only one pneumatic clip holding the two doors together and fixed to the second stage body;

Fairings use many bolts or devices (more than 5 and some in the tens) to hold them together.

Outward-opening hinges mounted on the inside. Steel springs, I assume. I'm saying they could be designed to open smoothly and rapidly enough.


To generate the forces and the acceleration required, they would have to huge and hence heavy

This is how fast a fairing comes off

https://www.youtube.com/watch?v=Fvte4KfEWGI
Title: Re: Fairing reuse
Post by: CyndyC on 04/02/2016 04:59 pm
Along with the video Jim posted, this video of a SpaceX fairing separation test might help with the brainstorming:

https://youtu.be/LtI1V624vWM
Title: Re: Fairing reuse
Post by: D_Dom on 04/02/2016 06:54 pm
Thank you Jim and CyndyC! I really enjoy good high speed imagery, it helps me understand the forces involved. The Atlas fairing flex as it separates for example. The SpaceX chamber test demonstrates their fine tuned inertia absorbing system, just amazing.
Title: Re: Fairing reuse
Post by: chalz on 04/04/2016 03:44 am
Suppose you wanted to add a parachute to try to make a fairing more survivable. Where on the fairing would you put it? Could the pushers handle the extra weight and would a change in CG affect the opening motion? I'm thinking they might have to attach a parachute halfway up the outside. Drill some holes in it and bolt it to it, maybe 100kg extra. Also perhaps a buoyancy aid will be necessary for the post splashdown procedure but SpaceX won't find that out until they can get one down in one piece.
Title: Re: Fairing reuse
Post by: Stan-1967 on 04/04/2016 06:24 am
The problem of fairing reuse is really lacking a problem statement(s) to drive potential solutions.

Take for example the problem of precision landing hoverslams:
1.  Pioneer the work to execute hypersonic retropulsion
2.  Slow the stage to "x" meters/sec., +- some value "y", at elevation "A"
3.  perform #2 velocity change with "M1" kg's of fuel and oxidizer.
4.  perform #2 & #3 above with +- 15 meters accuracy to a predetermined latitude/longitude coordinate
5.  Do all the above, but don't land at an angle and tip over and explode, don't break a leg and tip over and explode, don't have horizontal velocity and hit the barge and explode, don't run out of fuel and explode, etc. etc.

My point being is that the hoverslam maneuver first defined the vehicle orientation, stability, velocity change requirements, navigation requirements, and load tolerance requirements before SpaceX added all the systems that adapted mass trade-offs against them. ( i.e grid fins, landing legs, ASDS vs. RTLS, etc. )

So for fairing reuse, what are the problems?   How do they limit ( or eliminate ) the possible solutions?

Here is what I can come up with:
1.  The fairing needs to be slowed to a speed that does not fracture the composite structure no matter the orientation at impact.  ( let imaginations flow if this is to be done with parachutes, active flight control surfaces deployed, sliding the fairing down the side of S1 prior to MECO, rocket retropropulsion aka Soyuz capsule etc.)

2.  Methods proposed in #1 cannot jeopardize the payload, or be less reliable than existing disposable fairings.

3.  Landing accuracy needs to occur in a specified landing ellipse or search grid that is a 100X smaller area than a ballistic reentry with unstable aerodynamics.  Want a bigger margin for area?  How will you search it before winds & currents expand the search area to unmanagable proportion?

4.  The fairings cannot be left in the ocean for extended search times in excess of 24-36 hours.  Again want more time? fine, how will you home in on the fairing when wind, current, weather, and search resources make recovery moot.

5.  Allowable extra mass is 1000kg per half.   This addition penalizes S1 about 9200 kg's of extra fuel that cannot be used for RTLS or DPL, not to mention less mass to orbit.  If you want a bigger mass budget, fine.  It comes at the expense of S1 reuse probability, and could be the difference between RTLS or DPL, not to mention success or failure of S1 reuse.  If you can propose some method using less mass, great! Better chance for S1 re-use.
Title: Re: Fairing reuse
Post by: bioelectromechanic on 04/04/2016 12:58 pm
How much does it weight? dimensions? surface area? how much additional mass would systems require? will it require a change in the F9 flight profile? what is dV cost of the flight profile change?
Title: Re: Fairing reuse
Post by: cambrianera on 04/04/2016 08:06 pm

So for fairing reuse, what are the problems?   How do they limit ( or eliminate ) the possible solutions?


Nice post, I would like to add my comment.

Let me start with #2:
Would we discuss addition/tweaks to existing disposable fairings to avoid too many variables? This also not jeopardizes payload nor worsen reliability.

#1 Orientation is paramount, going convex first you can spread conveniently the shock wave at the atmospheric interface, then going concave first when subsonic you can slow down under 20 m/s of terminal velocity. I see deployable panels for convex first, and midsize drogues/parachutes for concave first.

#3 Radio beacons?

#4 Agree on search time, I think would be enough w radio beacon.

#5 I will start the "guesstimate" phase soon, but let me say 1000 kg is too much. Not more than 300 kg per half to avoid compounding effects on the fairing itself (more mass, more structure and so on)

Title: Re: Fairing reuse
Post by: Lars-J on 04/04/2016 08:20 pm
All this "fairing reuse" talk seems to be misleading. You don't want that. What you actually want - but somehow refuse to call it - is a payload bay with doors that can open and close. (like on Shuttle)

It's a certainly doable and a good idea for a reusable upper stage, but it will weigh significantly more and be a lot more complex. You need a lot of mass margin to pull it off.

(An upper stage with an integrated cargo bay is what I have been advocating for commercial BFR use, where margins would be plentiful)

But don't think of it is a "reused fairing". Think of it as a payload bay - it is a far more realistic approach.
Title: Re: Fairing reuse
Post by: OxCartMark on 04/04/2016 09:25 pm
All this "fairing reuse" talk seems to be misleading. You don't want that. What you actually want - but somehow refuse to call it - is a payload bay with doors that can open and close. (like on Shuttle)

It's a certainly doable and a good idea for a reusable upper stage, but it will weigh significantly more and be a lot more complex. You need a lot of mass margin to pull it off.

(An upper stage with an integrated cargo bay is what I have been advocating for commercial BFR use, where margins would be plentiful)

But don't think of it is a "reused fairing". Think of it as a payload bay - it is a far more realistic approach.

Then you'd be taking it all the way up and as has been hashed and re-hashed above won't work because taking the current fairing along for the whole ride cuts your payload to orbit in half and you're talking about making it weigh more and then taking it to orbit.  And not only do you pay the mass penalty once going up but you've also added more energy to the second stage that needs to be dissipated on the way down with thrust and with heating.  And, since under the scenario you propose it would have to survive re-entry at many times the speed that it currently hits at it would need to be made structurally stouter (heavier) to survive and would need a heat shield (more weight) if it is even possible to make a heat shield work on a piece of plastic.  My seat of the pants feel is that you'd reduce the payload to orbit to 1000 pounds but I may be off by a few thousand pounds and maybe it wouldn't be capable of going that fast.
Title: Re: Fairing reuse
Post by: savuporo on 04/04/2016 09:46 pm
Not sure if this is feasible or buys you anything much, but one could envision a system where separated sides fairing will remain connected via a tether. Definitely would require extra pyrotechnics to make the separation clean - and separation is risky as it is.
Title: Re: Fairing reuse
Post by: Jdeshetler on 04/05/2016 03:22 am
Speed up the slow motion of SpaceX fairing separation test back to "real time".
It moved faster than the test straps that is holding it.

https://youtu.be/k0MziXDlblU

This is how fast a fairing comes off
Title: Re: Fairing reuse
Post by: Stan-1967 on 04/05/2016 04:58 am
Not sure if this is feasible or buys you anything much, but one could envision a system where separated sides fairing will remain connected via a tether. Definitely would require extra pyrotechnics to make the separation clean - and separation is risky as it is.

Why is my brain having images of "Space Clackers"?

https://www.youtube.com/watch?v=7leq3vn8P3A

But seriously, to what effect would the tether do anything useful?  What benefit is derived from this?   What do you want to do with two fairing halves connected with a tether?
Title: Re: Fairing reuse
Post by: Stan-1967 on 04/05/2016 06:01 am

snip...

#1 Orientation is paramount, going convex first you can spread conveniently the shock wave at the atmospheric interface, then going concave first when subsonic you can slow down under 20 m/s of terminal velocity. I see deployable panels for convex first, and midsize drogues/parachutes for concave first.

#3 Radio beacons

 snip...


As to radio beacons, I think that not only could the fairings be instrumented with either radio beacons, but also sono emitters that could be picked up and triangulated with prepositioned sonobouys in the landing zone.  The tough part is still getting to a landing zone.

I get the convex/concave choices for managing shock and drag, but I am not sure a fairing (half) can maintain attitude control during re-entry, or during decent at terminal velocity.   Are you certain of the stability?  I do not know.   

It looks like it would have dynamic instability and tumble, roll, & spin all over the place.  Indeed I think figuring out the existing stability characteristics is a good starting point.  At the simple end of the spectrum, maybe a drogue chute can fix it, if that doesn't do the job, move on to deployable passive control surfaces, then active surfaces. 


I had another idea for stability.   Imagine the inside of each fairing to have a bladder ( thin rubber/plastic/composite?) lightly adhered ( think 3M yellow stick notes type of adhesion) to the inside surface of the composite fairing shell.   All the anechoic foams,insulation, & active sonic devices are layered on top of this bladder, and continue to perform the functions needed for the fairing environment.   The fairing can look and work just as the existing items currently do.

When the fairing is jettisoned, a COPV attached inside the fairing half will inflate the bladder, and the pressure of the gas will peel the bladder away from the inside of the fairing and inflate to a form that mirrors the composite fairing half, and once inflated the fairing will have virtually the same shape as a full fairing.  Most of the anechoic foams/insulation will pop off during this event.

What next?   I might want to try and spin it up for some stability, or I might try to have some passive aero surfaces spin it.   Whatever the method ( passive surfaces or drogue chute ) it takes to impart stability, that is what I want to solve.  The reason is so that it follows a stable ballistic trajectory, no tumbling, surfing, or gliding all over the downrange ocean.    This minimizes the area of the landing zone, and enables location and recovery.   At some point, maybe 2000'-3000' above sea level, it would deploy a chute for a soft landing at some angle on it's side, and preferably with the gas bladder impacting the ocean first. (like an airbag softening the impact)

Title: Re: Fairing reuse
Post by: JamesH65 on 04/05/2016 09:13 am

snip...

#1 Orientation is paramount, going convex first you can spread conveniently the shock wave at the atmospheric interface, then going concave first when subsonic you can slow down under 20 m/s of terminal velocity. I see deployable panels for convex first, and midsize drogues/parachutes for concave first.

#3 Radio beacons

 snip...


As to radio beacons, I think that not only could the fairings be instrumented with either radio beacons, but also sono emitters that could be picked up and triangulated with prepositioned sonobouys in the landing zone.  The tough part is still getting to a landing zone.


Isn't the obvious route for location to simple have a GPS + satellite link on board that transmits its exact location in real time? Cost and weight minimal, accuracy within 1m.
Title: Re: Fairing reuse
Post by: Jim on 04/05/2016 11:33 am

When the fairing is jettisoned, a COPV attached inside the fairing half will inflate the bladder, and the pressure of the gas will peel the bladder away from the inside of the fairing


How are you going to keep it in place and yet make inflation "peel" it off.
Title: Re: Fairing reuse
Post by: Stan-1967 on 04/05/2016 01:54 pm

When the fairing is jettisoned, a COPV attached inside the fairing half will inflate the bladder, and the pressure of the gas will peel the bladder away from the inside of the fairing


How are you going to keep it in place and yet make inflation "peel" it off.

Peeling it off is going to be an important trick.   I think adhesives engineered like this one would be candidates.

http://solutions.3m.com/wps/portal/3M/en_US/Adhesives/Tapes/Products/~/3M-Repositionable-75-Spray-Adhesive-Net-Wt-10-25-oz-12-per-case?N=5396314+4294924311&rt=rud

This class of adhesives have a storied past regarding the 3M Post-it-notes, however the adhesive can be engineered to adjust the strength/holding properties, but more importantly, the peel strength properties.   It needs to be strong enough to hold all the inner linings materials and insulation of the fairing to the bladder.   If you look at the mass of the fairing materials, and the very large surface area of the inside of the composite fairing shell, the holding strength is not very large in terms of Newtons/cm^2.   The peel strength probably the more critical property.   You need to get the inside of the bladder lifted from a small corner or edge, and then "unzip" the entire length of the assembly.
Title: Re: Fairing reuse
Post by: savuporo on 04/05/2016 03:43 pm
But seriously, to what effect would the tether do anything useful?  What benefit is derived from this?   What do you want to do with two fairing halves connected with a tether?
You could have the tether reel in a few seconds after clean separation, pulling the sides together. This might make the reentry tumble more survivable, or worse. No idea - just an idle thought
Title: Re: Fairing reuse
Post by: cambrianera on 04/05/2016 07:00 pm
But seriously, to what effect would the tether do anything useful?  What benefit is derived from this?   What do you want to do with two fairing halves connected with a tether?
You could have the tether reel in a few seconds after clean separation, pulling the sides together. This might make the reentry tumble more survivable, or worse. No idea - just an idle thought
I thought to that. Fishing reels are reliable, small mass, small friction devices that can be modified on purpose.
Still remaining important issues:
-risk of tangling into payload (or between tethers, if more than one);
-rejoining of halves to be completed by other devices (hooks, clamps or similar);
-terminal velocity probably too high to survive sea impact (need some other device).

Assuming the same mass, obviously separate halves have smaller mass/surface ratio.

Title: Re: Fairing reuse
Post by: llanitedave on 04/05/2016 07:02 pm
The fairing is not that heavy, and it's already relatively robust as it is.  I think it might not need anything more than a small drogue chute and a homing device, at least for starters.
Title: Re: Fairing reuse
Post by: cambrianera on 04/05/2016 07:11 pm

I had another idea for stability.   Imagine the inside of each fairing to have a bladder ( thin rubber/plastic/composite?) lightly adhered ( think 3M yellow stick notes type of adhesion) to the inside surface of the composite fairing shell.   All the anechoic foams,insulation, & active sonic devices are layered on top of this bladder, and continue to perform the functions needed for the fairing environment.   The fairing can look and work just as the existing items currently do.

When the fairing is jettisoned, a COPV attached inside the fairing half will inflate the bladder, and the pressure of the gas will peel the bladder away from the inside of the fairing and inflate to a form that mirrors the composite fairing half, and once inflated the fairing will have virtually the same shape as a full fairing.  Most of the anechoic foams/insulation will pop off during this event.


Intriguing idea, but I see a couple of important drawbacks:
-mass. The bladder should have some structural integrity, otherwise should not stand the stresses of peeling, mantaining a pressure enough to stabilize against airflow and finally splashdown; this having the same surface as a fairing half.
-reusability. You basically throw away all the internal parts of the fairing, moreover you have to reapply the bladder to the half fairing (assuming the bladder itself can be reused).
Title: Re: Fairing reuse
Post by: savuporo on 04/05/2016 07:20 pm
-risk of tangling into payload (or between tethers, if more than one);
If you had three sided fairing, tangling potential could be maybe smaller, if there are three tethers connecting the corners. Hard to clear the rocket with two-halve clamshell fairing, would need extra pyro gear or something
Title: Re: Fairing reuse
Post by: cambrianera on 04/05/2016 07:46 pm
-risk of tangling into payload (or between tethers, if more than one);
If you had three sided fairing, tangling potential could be maybe smaller, if there are three tethers connecting the corners. Hard to clear the rocket with two-halve clamshell fairing, would need extra pyro gear or something

True, but three sided fairings should call for more joints, more pushers, more mass overall.
But not a given, maybe interesting.
Tangling of the tethers still remain a possibility, and rejoining three pieces requires more effort.
Title: Re: Fairing reuse
Post by: cambrianera on 04/05/2016 07:49 pm

I get the convex/concave choices for managing shock and drag, but I am not sure a fairing (half) can maintain attitude control during re-entry, or during decent at terminal velocity.   Are you certain of the stability?  I do not know.   


Thinking to something like this, very light.
For first part, reentry, managing the shock
Title: Re: Fairing reuse
Post by: CraigLieb on 04/05/2016 08:21 pm
How about the fairings split into 28.3 degree sections, sprout little wings,  with small jet engines that pop out, and fly themselves independently down to a specially designed run-way like a mini-shuttle?   ::)
Please no serious replies.  This was meant as a joke to point out how little value there is in trying to engineer a solution here.
Title: Re: Fairing reuse
Post by: llanitedave on 04/05/2016 11:37 pm
Perhaps if we built a large, wooden badger...



Title: Re: Fairing reuse
Post by: sewebster on 04/06/2016 02:13 am
Then you'd be taking it all the way up and as has been hashed and re-hashed above won't work because taking the current fairing along for the whole ride cuts your payload to orbit in half and you're talking about making it weigh more and then taking it to orbit.  And not only do you pay the mass penalty once going up but you've also added

Not that I'm advocating for taking the fairing to orbit, but does it really have a mass of half the payload? Do we know the mass? (maybe I just forget from upthread...)
Title: Re: Fairing reuse
Post by: D_Dom on 04/06/2016 02:22 am
The weight of the fairing must be overcome by burning rocket fuel. The mass of the fuel is dictated by the rocket equation. It is not that mass of the fairing is equal to half the payload, it is the tyranny of the rocket equation that cuts the payload mass if you carry the fairing further than absolutely necessary.
Title: Re: Fairing reuse
Post by: sewebster on 04/06/2016 02:41 am
The weight of the fairing must be overcome by burning rocket fuel. The mass of the fuel is dictated by the rocket equation. It is not that mass of the fairing is equal to half the payload, it is the tyranny of the rocket equation that cuts the payload mass if you carry the fairing further than absolutely necessary.

Right, but presumably the worst case scenario is subtracting the fairing mass from the maximum payload mass (if you take the fairing to orbit)? In reality it isn't this bad, because you were already planning on taking the fairing up part of the way?
Title: Re: Fairing reuse
Post by: savuporo on 04/06/2016 02:53 am
Right, but presumably the worst case scenario is subtracting the fairing mass from the maximum payload mass (if you take the fairing to orbit)? In reality it isn't this bad, because you were already planning on taking the fairing up part of the way?
Its this bad, as fairing separates roughly after 1/3rd of the flight time. For the rest of the 2/3rd of flight, you are not trying to accelerate that weight.
Title: Re: Fairing reuse
Post by: OxCartMark on 04/06/2016 02:48 pm
In my opinion the combined productive benefit of the preceding 15 pages is about as useful to human endeavor as a parachute on a well driller.
Title: Re: Fairing reuse
Post by: Lar on 04/06/2016 04:26 pm
Mod here: I've been trying to figure out how to split out the "what they could do" from "what we think... based on evidence, that SpaceX IS doing". I couldn't find a good set of posts to split out, but I'm trying.

Maybe the way to go is to start a new thread that focuses only on the evidence, and stays narrowly focused, and leave this thread for those folks that want to come up with ever wilder schemes.... (not me, so much, I'm more interested in the kremlinology around what SpaceX appears to actually be doing)  I will continue to try to find a way to split but if not, will lock this, and start two threads.
Title: Re: Fairing reuse
Post by: dorkmo on 04/06/2016 10:27 pm
known spacex advances:
thrusters to control orientation
go pros to record fall
possible extra recovery ship
a few statements about recovery intentions
?

i vote for one thread to speculate at will. its not perfect but we dont have much to go on in the first place.
(says the guy that thinks they could dock the two halves together lulz)
Title: Re: Fairing reuse
Post by: llanitedave on 04/06/2016 10:42 pm
Maybe we need a fairing Bingo thread.
Title: Re: Fairing reuse
Post by: wannamoonbase on 04/07/2016 12:28 am
known spacex advances:
thrusters to control orientation
go pros to record fall
possible extra recovery ship
a few statements about recovery intentions
?

i vote for one thread to speculate at will. its not perfect but we dont have much to go on in the first place.
(says the guy that thinks they could dock the two halves together lulz)

This whole development is exciting and interesting.  They'll likely proceed incrementally and slowly and we won't know how far they are until they succeed.  I'd bet they start with recovering one half first.

With all the developments they have going on, if they try hooking one in the next year that would be pretty quick in my opinion.
 
Title: Re: Fairing reuse
Post by: cscott on 04/07/2016 02:45 pm
I like the two thread idea.  It's obvious (to me) that SpaceX is recovering the fairing halves individually, and is experimenting with RCS mechanisms to stabilize them.  The outlandish clamshell and tether ideas here have no evidence supporting them -- putting aside completely the question of their practicality, superiority, etc.  Sign me up for the low-volume thread discussing actual *evidence* and theories grounded in that evidence.  I have no problem with folks continuing to try to "build a better mousetrap"... I'm just not personally interested in following that thread.

Ob. Fairing news: in the ASDS thread we've noticed that Go Searcher, who has gone out for recovery attempts involving fairings, is staying in port for the dragon launch (which doesn't involve a fairing).  We'll see if this pattern holds, but it's beginning to look like evidence for a "fairing recovery" role for Go Searcher.
Title: Re: Fairing reuse
Post by: D_Dom on 04/07/2016 04:09 pm
Huge benefit to people unfamiliar with the statement "space is hard" is that on this site you can ask any questions you like and expect a responsible answer. Agreed that some of the topics on this thread defy all the known laws of physics, so be it. Also thinking of channeling Jim for one word responses if only just to increase the number of replies I have time for. Not at all offended by having to wade through the outlandish ideas to consider the "evidence". My humble opinion is leave it as one thread, cultivate the signal, address the noise (respectfully) and we may all learn something about this most interesting aspect of re-usability.
Title: Re: Fairing reuse
Post by: Space Ghost 1962 on 04/07/2016 04:16 pm
... and do your own reading/searching/research on the substantial body of what has been attempted already.

For example, Kistler K-1 was to be a TSTO 100% reusable vehicle, which had ... a kind of fairing that was reused.

Also, keep in mind that some conceived ideas change as you take a concept and put it into action. For example, Dragon's solar panels were encased inside the trunk and a complex articulation of booms deployed them - never flown - they chose to mount them on the side for a simpler deploy with jettisoned fairings.

Ask yourself "why" these decisions were/are made first. Think of the trades for each.
Title: Re: Fairing reuse
Post by: D_Dom on 04/07/2016 04:27 pm
In my opinion the combined productive benefit of the preceding 15 pages is about as useful to human endeavor as a parachute on a well driller.

Having jumped out of perfectly good airplanes before I can see the advantage of "dropping in" heavy equipment to a remote site. just saying...
Title: Re: Fairing reuse
Post by: manoweb on 04/08/2016 11:15 pm
Today at the press debriefing Mr. E. Musk mentioned they are pursuing fairing reuse, because it costs several million dollars.
Title: Re: Fairing reuse
Post by: Mader Levap on 04/08/2016 11:17 pm
Today at the press debriefing Mr. E. Musk mentioned they are pursuing fairing reuse, because it costs several million dollars.
Wouldn't that be first official mention of fairing reuse?
Title: Re: Fairing reuse
Post by: mlow on 04/08/2016 11:20 pm
The way I heard it, sounded like he was referring to couple mil each.
Title: Re: Fairing reuse
Post by: iamlucky13 on 04/09/2016 02:58 am
Yes, and estimated costs in the $5-6 million range for the similarly sized Ariane 5 fairing, which is also composite, have been documented further up thread. Fairings are more complicated structures than most people realize.

I'm pretty sure this is the first public mention of fairing recovery plans.
Title: Re: Fairing reuse
Post by: leetdan on 04/09/2016 05:34 am
Today at the press debriefing Mr. E. Musk mentioned they are pursuing fairing reuse, because it costs several million dollars.
Wouldn't that be first official mention of fairing reuse?

Fairing reuse has been mentioned in response to people posting images of fairing fragments washing up elsewhere.

My questions is, have we officially heard anything about thrusters on the fairing?  I know people 'saw something' in the SES-9 launch videos, but has SpaceX ever confirmed what we were seeing?
Title: Re: Fairing reuse
Post by: meekGee on 04/09/2016 06:05 am
Today at the press debriefing Mr. E. Musk mentioned they are pursuing fairing reuse, because it costs several million dollars.
Wouldn't that be first official mention of fairing reuse?

Fairing reuse has been mentioned in response to people posting images of fairing fragments washing up elsewhere.

My questions is, have we officially heard anything about thrusters on the fairing?  I know people 'saw something' in the SES-9 launch videos, but has SpaceX ever confirmed what we were seeing?
There was informal but credible info on L2 for a while now.
Title: Re: Fairing reuse
Post by: mikelepage on 04/09/2016 10:25 am
Some "fairing blimp" calculations: feel free to skip.

Coming over from the airship thread, and reading upthread about the potential for having some kind of bladder on the inside of the fairing, I just wanted to do a back of the envelope on the possibility of converting each fairing half into a lighter-than-air craft before it reaches the ground.  Could inform potential Venus airship mission too.

Total fairing weight for the 13.1x5.2m ("bus containing") is supposed to be 1750kg.  Dividing that by 2 gives 875kg per half:
Pre-empting the results below, I'm assuming we're adding 225kg per half to take it to 1100kg per half:

1) Amount of Helium required to provide equivalent buoyancy force:
Each mole of Helium is 4 grams, displaces ~29g of atmosphere, and expands to 22.4 L at STP.
1100000g fairing half/ 25g = 44000 moles of helium (176kg).
At STP that would fill a bladder to ~985.6m3 (call it 1000m3)

2) Assuming the bladder expands to a cylinder 13.1m long capped with hemispheres
V = 4/3πr3 + 26.2πr
r ~ 5.2 m

3) Surface area of inflated bladder
5.2π*13.1+ 4π(5.2)2 = 340m2
Standard blimp envelope material seems to be 80-90g per m2
giving us 30.6kg of envelope material.

Not really sure of the weight/size requirements of the helium gas canister you'd need, but it seems to me this could be within the realms of workability, if you can have some kind of drogue chute that would keep the fairing somewhat oriented to protect the bladder material on the way down.
Title: Re: Fairing reuse
Post by: Radical_Ignorant on 04/09/2016 10:54 am
Many  here like the idea of keeping both pieces connected and closing them before reentering atmosphere. I find it compelling as connected they create shape which seems to be much more stable. And easier to keep afloat.

And how to keep them connected? Well, I see on the video were they test separation mechanism that both parts are connected, so it seems possible. And in old days there were those rockets controlled by cables, so there are things which can survive and do the job.

But then is it required at all? Pieces found are pretty large, so maybe it's enough to reduce impact speed (with water) by small parachute and no need anything more than orienting it on the start to protect the parachute from burning in initial phase.

But still I'm intrigued if connection as on test video could be used with some minor modifications in real mission.
Title: Re: Fairing reuse
Post by: Jim on 04/09/2016 01:49 pm

And how to keep them connected? Well, I see on the video were they test separation mechanism that both parts are connected, so it seems possible. And in old days there were those rockets controlled by cables, so there are things which can survive and do the job.


not true on either point.  The cables would put loads on the fairings and there is no way to bring them together in a controlled matter without them slamming together.

Which rockets were controlled by cables?
Title: Re: Fairing reuse
Post by: tyrred on 04/09/2016 03:25 pm
May be a reference to TOW missiles (Tube-launched Optically tracked Wire-guided)?
Title: Re: Fairing reuse
Post by: Radical_Ignorant on 04/09/2016 04:31 pm

And how to keep them connected? Well, I see on the video were they test separation mechanism that both parts are connected, so it seems possible. And in old days there were those rockets controlled by cables, so there are things which can survive and do the job.


not true on either point.  The cables would put loads on the fairings and there is no way to bring them together in a controlled matter without them slamming together.

Which rockets were controlled by cables?

Of course that they would put loads, and so? This load would be symetric, fairings would be tiny bit heavier.
No way to bring them together? You mean that it's impossible to control  force required to pull the cable? Or you say that using force in only one way it's not possible to gently stop momentum? Like for example on rocket falling from the sky? Or you claim that TOWs (thanks tyrred - I was lazy) weren't working because there is no cable which could easily withstand rocket exhaust?

It's always super easy to claim "no it's impossible". But that's rarely true. That would be too hard, or that would not be cost effective, or that could be dangerous/not reliable because of... that I could believe.
Title: Re: Fairing reuse
Post by: llanitedave on 04/09/2016 04:53 pm

And how to keep them connected? Well, I see on the video were they test separation mechanism that both parts are connected, so it seems possible. And in old days there were those rockets controlled by cables, so there are things which can survive and do the job.


not true on either point.  The cables would put loads on the fairings and there is no way to bring them together in a controlled matter without them slamming together.

Which rockets were controlled by cables?

Of course that they would put loads, and so? This load would be symetric, fairings would be tiny bit heavier.
No way to bring them together? You mean that it's impossible to control  force required to pull the cable? Or you say that using force in only one way it's not possible to gently stop momentum? Like for example on rocket falling from the sky? Or you claim that TOWs (thanks tyrred - I was lazy) weren't working because there is no cable which could easily withstand rocket exhaust?

It's always super easy to claim "no it's impossible". But that's rarely true. That would be too hard, or that would not be cost effective, or that could be dangerous/not reliable because of... that I could believe.


How about "it's simply unnecessary."
Title: Re: Fairing reuse
Post by: Stan-1967 on 04/09/2016 05:42 pm

And how to keep them connected? Well, I see on the video were they test separation mechanism that both parts are connected, so it seems possible. And in old days there were those rockets controlled by cables, so there are things which can survive and do the job.


not true on either point.  The cables would put loads on the fairings and there is no way to bring them together in a controlled matter without them slamming together.

Which rockets were controlled by cables?

Of course that they would put loads, and so? This load would be symetric, fairings would be tiny bit heavier.
No way to bring them together? You mean that it's impossible to control  force required to pull the cable? Or you say that using force in only one way it's not possible to gently stop momentum? Like for example on rocket falling from the sky? Or you claim that TOWs (thanks tyrred - I was lazy) weren't working because there is no cable which could easily withstand rocket exhaust?

It's always super easy to claim "no it's impossible". But that's rarely true. That would be too hard, or that would not be cost effective, or that could be dangerous/not reliable because of... that I could believe.

I'll try offer my criticism, and not just dismissal.  Although I would add that "dismissal", when it comes from many veteran sources pretty clued into real world experience with space hardware, is a good hint that an idea may not be great.   I like that this site because it has threads that allow some speculation.  Maybe this thread should be split, as the MOD has indicted he is considering.  I do think a thread based solely on what we "know", would be about 10 posts long, and boring.   Most of us here are probably of a technical/engineering background, and so we have PI's that either like to ruminate endlessly over such speculation, or we don't suffer fools, and dismiss things with little tact or feeling when we are so inclined.

So back to the topic of cables....

I don't think the cables seen in the SpaceX fairing test video from the Plum Brook facility indicate in any way that cables would work like this in a freefall/zero-g environment.   It's nice to imagine in our gravitationally conditioned minds that the fairings will magically come back together and reattach.  That's because our earth environment conditions our minds with lots of dampening and frictional forces.   

It's too easy to think of this problem like a household vacuum cord automatically winding itself back inside the appliance housing, but it just won't work like that.  Each pull of the cord/cable on attached fairing halves will accelerate the halves in the direction of the pull.   Unless the vector of that acceleration exactly moves the halves to a rendezvous, they will impact obliquely, & spin apart from each other from an in-elastic collision, and not rendezvous.   Furthermore, once they are accelerating towards each other, cables cant slow them down.   Ever try making compression forces with a string?  That means RCS and sensors, and you may as well eliminate the cables entirely.   I see a a big tangled mass of cable and fairing resulting after a few collisions together.
Title: Re: Fairing reuse
Post by: Stan-1967 on 04/09/2016 05:49 pm

And how to keep them connected? Well, I see on the video were they test separation mechanism that both parts are connected, so it seems possible. And in old days there were those rockets controlled by cables, so there are things which can survive and do the job.

It is not the cable that control the rocket, ( i.e TOW's) but electrical signals sent through the cable.  The cable is spooled out behind the rocket in a manner that tries to eliminate or reduce any drag or moments that affect the rockets guided flight path.   
Title: Re: Fairing reuse
Post by: Stan-1967 on 04/09/2016 05:57 pm

Thinking to something like this, very light.
For first part, reentry, managing the shock

http://forum.nasaspaceflight.com/index.php?topic=37727.msg1511754#msg1511754

I'd like it even more if it worked in a passive mode, vs. needing active control.  Something like this seems simple if it can keep the orientation stable.   So assuming this method keeps it stable and gets it into a landing zone, would you still need a parachute for soft landing?
Title: Re: Fairing reuse
Post by: cambrianera on 04/09/2016 06:08 pm

Thinking to something like this, very light.
For first part, reentry, managing the shock

http://forum.nasaspaceflight.com/index.php?topic=37727.msg1511754#msg1511754

I'd like it even more if it worked in a passive mode, vs. needing active control.  Something like this seems simple if it can keep the orientation stable.   So assuming this method keeps it stable and gets it into a landing zone, would you still need a parachute for soft landing?

No active control needed to keep it stable, basically  the shuttlecock principle.

Parachute still needed for softer landing.
Reorienting the half fairings concave first, drag increases two-three fold (plus parachute drag).
Title: Re: Fairing reuse
Post by: Stan-1967 on 04/09/2016 06:14 pm
Some "fairing blimp" calculations: feel free to skip.

Coming over from the airship thread, and reading upthread about the potential for having some kind of bladder on the inside of the fairing, I just wanted to do a back of the envelope on the possibility of converting each fairing half into a lighter-than-air craft before it reaches the ground.  Could inform potential Venus airship mission too.

Snip...

Not really sure of the weight/size requirements of the helium gas canister you'd need, but it seems to me this could be within the realms of workability, if you can have some kind of drogue chute that would keep the fairing somewhat oriented to protect the bladder material on the way down.

Thanks for doing those calcs.  I did some BOE that suggested the mass of the HE gas would be much less than the flexible bladder material.  My point in the bladder idea was not to make it "lighter than air" but to give it a shape that would be stable during a ballistic re-entry, and thereby aid in a smaller recovery zone.  Furthermore, if it could be landed with the bladder impacting the ocean as a type of "airbag", it would aid in preservation.

I think the adhesion of the bladder to the composite shell would be tricky, but doable.   Jim and others pointed out that problem.   It didn't seem overly complex to me, certainly not trivial.    It is very likely more simple methods would be tested long before the wilder ideas tossed around here.

1. nothing..just find it floating in the ocean
2. Some sort of controlled impact achieved with deployable control surfaces
3. Impact with drogue chute orienting the impact
4. Drogue chute plus bigger parachute orienting the impact
5. other ideas.
Title: Re: Fairing reuse
Post by: bstrong on 04/09/2016 06:29 pm
Today at the press debriefing Mr. E. Musk mentioned they are pursuing fairing reuse, because it costs several million dollars.
Wouldn't that be first official mention of fairing reuse?
Elon mentioned it in a tweet last year:

https://twitter.com/elonmusk/status/605460768516014080
Title: Re: Fairing reuse
Post by: Space Ghost 1962 on 04/09/2016 06:44 pm
Before you design a system, you must appreciate the environment of an existing system, what occurs in the life cycle of use, what qualities / requirements you have for the new system that the old one didn't have. E.g. aclear statement of the problem.

If I understand this wandering thread, what is desired is a jettisonable multipart fairing that largely works as the current one has done, but retains the integrity/registration/tensile qualities/compression/other of the fairing so that after its located/recovered, it can be economically remanufactured/reprocessed and qualified for reuse without refabrication?

The environment of this is to undergo payload/launch integration with US/LV, launch, ascent, staging, jettison ... as before. Then, either passively/actively negotiate the dissipation of extreme frictional heating and dynamic aeroloads in increasing atmospheric densities with decreasing velocities, until near terminal velocity and ocean impact.

And like the original system, you don't wish to greatly increase the mass penalty that robs from payload to orbit.

A lesser cost possibly is the drag of the system, so within the trades might be a larger effective diameter design with a hypothetical "fluffier" construction of some kind.

Also within the trades might be a design where the inside is much like the outside which already handles the ascent environment, with all the other requirements handled by stage or payload adapter or jettisonable (structure only reusable).

Next - prior experience. What allows past fairings to survive intact, and not others? When we compare a best case to an unused one, how has it been affected that makes the best case undesireable for reuse. What now do we have to preserve that we didn't before, and how do we instrument/test/prove such through consecutive flight, such that we converge on a useful solution.

All of this discussions would make this thread more focused and useful to address the topic.

Or is this just more jawing about random things that appeal or not?

add:
Approaches:
a) more durable version of the existing two part design (refinement)
b) reduced ballistic coefficient design with more, smaller components that each more easily survive to surface  (divide and conquer)
c) active structure that reconfigures post jettision to adapt to descent environment for better survival of structure (vehicle/glider?)
Title: Re: Fairing reuse
Post by: savuporo on 04/09/2016 06:53 pm
If I understand this wandering thread, what is desired is a jettisonable multipart fairing that largely works as the current one has done, but retains the integrity/registration/tensile qualities/compression/other of the fairing so that after its located/recovered, it can be economically remanufactured/reprocessed and qualified for reuse without refabrication?
Is symmetrical separation a must have ? Or can upper stage RCS deal with asymmetries ?

EDIT: also, what are the reasonable time limits for separation event ? A few seconds ? or tens of seconds ?
Title: Re: Fairing reuse
Post by: Space Ghost 1962 on 04/09/2016 07:13 pm
If I understand this wandering thread, what is desired is a jettisonable multipart fairing that largely works as the current one has done, but retains the integrity/registration/tensile qualities/compression/other of the fairing so that after its located/recovered, it can be economically remanufactured/reprocessed and qualified for reuse without refabrication?
Is symmetrical separation a must have ? Or can upper stage RCS deal with asymmetries ?


Symmetrical stress/loading is a must due to dynamic loads on launch. This dictates design and leads to fewer surprises in separation. Fabrication/test/qualification of symmetric parts simplifies proving such a design.

Titan had a triple gore design. There have been some unusual shrouds on certain payload in the past.

If you have any asymmetry/complexity, you risk recontact with the stage/payload. The more components/differences, the greater the risk.

That said, yes, such a design could possibly be made to work. The hard part would be proving that it always would work.

When you jettision, aeroloads are at a minimum by definition. The lower you jettison, the more mass you don't carry. Too low and the delicate payload is at risk.

add:
Quote

EDIT: also, what are the reasonable time limits for separation event ? A few seconds ? or tens of seconds ?
Sorry. Too quick.

We're talking seconds. Otherwise you are coasting, which for the ascent you are planning may not be feasible. And to be fair, coasts of a hundred seconds can occur, although likely not optimal.

Another item with asymmetry. Your payload and vehicle stack have to have at least a well known center of mass that you thrust through. If you partial jettison or asymmetric part jettison , your center of mass will shift, which you may or may not be able to compensate for in various ways - how do you avoid the cosine loss or attitude change?
Title: Re: Fairing reuse
Post by: savuporo on 04/09/2016 07:30 pm
Symmetrical stress/loading is a must due to dynamic loads on launch. This dictates design and leads to fewer surprises in separation. Fabrication/test/qualification of symmetric parts simplifies proving such a design.

Titan had a triple gore design. There have been some unusual shrouds on certain payload in the past.

If you have any asymmetry/complexity, you risk recontact with the stage/payload. The more components/differences, the greater the risk.

That said, yes, such a design could possibly be made to work. The hard part would be proving that it always would work.

When you jettision, aeroloads are at a minimum by definition. The lower you jettison, the more mass you don't carry. Too low and the delicate payload is at risk.
Well, any gadget you add beyond current system is always an added risk anyway. Question is, is the risk manageable and worth it.

For example, the two current fairing halves could be joined by servoed hinges on one side that fully opens one side before separation push, and then push it to one side. But thats a huuge asymmetry, not sure if this is remotely feasible.

The point would be to close clamshell again after separation to have the same aerodynamic shape reenter that went up. And then do trailing ballute, streamer or parachute or whatnot to survive the splash
Title: Re: Fairing reuse
Post by: Space Ghost 1962 on 04/09/2016 07:45 pm
Symmetrical stress/loading is a must due to dynamic loads on launch. This dictates design and leads to fewer surprises in separation. Fabrication/test/qualification of symmetric parts simplifies proving such a design.

Titan had a triple gore design. There have been some unusual shrouds on certain payload in the past.

If you have any asymmetry/complexity, you risk recontact with the stage/payload. The more components/differences, the greater the risk.

That said, yes, such a design could possibly be made to work. The hard part would be proving that it always would work.

When you jettision, aeroloads are at a minimum by definition. The lower you jettison, the more mass you don't carry. Too low and the delicate payload is at risk.
Well, any gadget you add beyond current system is always an added risk anyway. Question is, is the risk manageable and worth it.

Yes. Likely negligible gain just from the start. Have to have significant advantage. Like forming a reentry vehicle w/o much additional cost.

Quote
For example, the two current fairing halves could be joined by servoed hinges on one side that fully opens one side before separation push, and then push it to one side. But thats a huuge asymmetry, not sure if this is remotely feasible.

The point would be to close clamshell again after separation to have the same aerodynamic shape reenter that went up.

The asymmetries also affect the flight of the payload + US.

Here's a rude thought. You jettison with a hinge that opens, and the halves later "bounce" and relatch ;)

Now for the downsides of any of these. You have three vehicles that have to be axis symmetric/stable for flight - the original launch stack, the payload+US, and the reformed fairing/shroud.

And, to avoid recontact, you'd have to guarantee that the separation planes (two, not one)  could never be coincident - e.g. it "sticks" in one or both and the still combined fairing "tilts" into the payload.

Quote
And then do trailing ballute, streamer or parachute or whatnot to survive the splash

Separate issue entirely. Make it into a hypersonic glider.
Title: Re: Fairing reuse
Post by: cambrianera on 04/09/2016 07:50 pm

The point would be to close clamshell again after separation to have the same aerodynamic shape reenter that went up. And then do trailing ballute, streamer or parachute or whatnot to survive the splash

The shape that went up is not optimal for reentry.
It probably has a stable attitude, but the two half fairing have half mass/surface, therefore more chances to survive reentry (if stabilized).
Title: Re: Fairing reuse
Post by: Space Ghost 1962 on 04/09/2016 07:54 pm

The point would be to close clamshell again after separation to have the same aerodynamic shape reenter that went up. And then do trailing ballute, streamer or parachute or whatnot to survive the splash

The shape that went up is not optimal for reentry.
It probably has a stable attitude, but the two half fairing have half mass/surface, therefore more chances to survive reentry (if stabilized).

Yes, and the mass distribution will be all wrong as well for return/recovery "flight".

What you'd be after is some kind of "nested" (or recursive) design, where the offsets in one are balanced by the others. Not an easy design challenge.

The cost of jettison isn't cheap here. Remember, you could lose a mission in saving a buck.
Title: Re: Fairing reuse
Post by: Joel on 04/09/2016 08:51 pm
Is it out of the question to have the fairing separation event coincide with MECO and let the fairings attach to the first stage? From my understanding, MECO now happens at around 80 km (correct me if I'm wrong) which is not that far from space.

Doesn't the desire to eventually reuse the entire rocket suggest that the first stage needs to stage later in order to give more margin to the second stage?
Title: Re: Fairing reuse
Post by: cambrianera on 04/09/2016 09:05 pm
Is it out of the question to have the fairing separation event coincide with MECO and let the fairings attach to the first stage? From my understanding, MECO now happens at around 80 km (correct me if I'm wrong) which is not that far from space.

Doesn't the desire to eventually reuse the entire rocket suggest that the first stage needs to stage later in order to give more margin to the second stage?

Look at page 11 (all page, but specially this post http://forum.nasaspaceflight.com/index.php?topic=37727.msg1507081#msg1507081 )
Title: Re: Fairing reuse
Post by: savuporo on 04/09/2016 09:11 pm
The cost of jettison isn't cheap here. Remember, you could lose a mission in saving a buck.
Yeah but that somewhat of a weak argument for a rocket that already sprouted legs and grid fins. And yes, these are on first stage, but losing the payload with the first stage pays just as little as screwing up fairings or something else later.
Title: Re: Fairing reuse
Post by: robert_d on 04/10/2016 12:28 am
So Here is a (just notional) picture based on the fact that E. Musk is really trying to find a way to reuse the fairings.
It assumes 1) that no possible set of equipment could be mounted within the fairing that would guarantee reuse. 2) No possible means will be found to rejoin the halves; and 3) the deceleration/reentry must include added energy and not just rely on a passive system. I understand the weight penalty such an idea entails. But in theory that could be offset a bit by firing the outer engines starting just before MECO and until fairing separation. Still to be determined would be final landing method. Dropping it directly into the ocean seems counter to the whole idea of reuse.
Title: Re: Fairing reuse
Post by: meekGee on 04/10/2016 12:33 am
There's another idea that was batted around a long time ago.

Have fairing retract, as a whole cylinder, onto the first stage, and return with it.

What's left around the pilot is a light cover that's sufficient to protect the payload against the residual atmosphere at 100 km.

(I believe that this damage is from the speed of the flow, but that the actual force on the payload is very low)

The clear negative is that you need to separate this secondary cover as well.

The positives are that A) you carry the heavy payload to a lower altitude, and B) that they come back with the first stage and so don't need an additional recovery mechanisms, helicopters, etc.

EDIT:  To clarify - this is just blue sky thinking.   The plan right now is clearly to parachute the two individual halves, and then recover mid-air.
Title: Re: Fairing reuse
Post by: robert_d on 04/10/2016 01:04 am
Just had another thought. Make second stage 5 meters like the original fairing but then mount the payload BEHIND the second stage propellant tanks. Interstage would then be just really long.  Engine bell would swing away on a hing just before the payload deploys behind the tanks. How's THAT for the crazy meter?
Title: Re: Fairing reuse
Post by: CJ on 04/10/2016 01:07 am
I'll take a stab at reading the tea leaves here, based on what's known plus some wild theorizing on my part as to what SpaceX might have in mind.

Okay, what's known? I'm taking it as a given that they want to recover and reuse fairings. I'm also taking it as a given that one of the fairing halfs had a cold gas thruster of some sort on SES9.

So here's my wild guesswork; the eventual plan is to, via very tiny clod gas thrusters, stabilize the fairing halfs so that they are enter outside-first (sort of like a boat floating) relative to the velocity vector. To damp out oscillation and impart a little stability, spin them at a few RPM (with the rotational axis aligned with the velocity vector). Based on what we've seen washed up, that might (I'm guessing) get them past the reentry.

After reentry, deploy a small drogue chute on a strong line. Assuming the fairings can't be immersed in salt water (?) this line and drogue could be snagged by a helicopter with the correct gear.

It would be far easier if the fairings could be immersed in salt water, assuming their terminal velocity (perhaps aided by a small drogue) would make water impact survivable, but I don't know whether that's feasible.

For location and tracking in either case, a small GPS-based transponder could be used. 

 
Title: Re: Fairing reuse
Post by: Radical_Ignorant on 04/10/2016 07:22 am

And how to keep them connected? Well, I see on the video were they test separation mechanism that both parts are connected, so it seems possible. And in old days there were those rockets controlled by cables, so there are things which can survive and do the job.


not true on either point.  The cables would put loads on the fairings and there is no way to bring them together in a controlled matter without them slamming together.

Which rockets were controlled by cables?

Of course that they would put loads, and so? This load would be symetric, fairings would be tiny bit heavier.
No way to bring them together? You mean that it's impossible to control  force required to pull the cable? Or you say that using force in only one way it's not possible to gently stop momentum? Like for example on rocket falling from the sky? Or you claim that TOWs (thanks tyrred - I was lazy) weren't working because there is no cable which could easily withstand rocket exhaust?

It's always super easy to claim "no it's impossible". But that's rarely true. That would be too hard, or that would not be cost effective, or that could be dangerous/not reliable because of... that I could believe.


How about "it's simply unnecessary."

Could you then please explain me what is necessary? I could believe that all is really required it's to reduce speed of impact with water. Pieces found are already quite large, so it would be believable.
Can you then help me and explain what for are those tests with controlling them? What could it help?
Title: Re: Fairing reuse
Post by: Radical_Ignorant on 04/10/2016 07:54 am
{....}

I'll try offer my criticism, and not just dismissal.  Although I would add that "dismissal", when it comes from many veteran sources pretty clued into real world experience with space hardware, is a good hint that an idea may not be great.   
{....}
This is wrong. I'm not disrespecting his opinion, I'm not even saying he is wrong and I'm right. All I was saying is that he provided nothing more than an opinion. And if something is valid because senior engineer said that - that is argument from person, from authority, not from fact. It's no educational value or no value at all. It's more an order than an answer "I'm senior here, be quiet and listen". And there is infinite amount of examples where senior (old, experienced) space guys were wrong :p

Sure I understand that lot of you folks are tired of our ignorance and dumb ideas. But then patience and politeness are things thanks to which we could admire your knowledge and learn from this forum even more.

So back to the topic of cables....

I don't think the cables seen in the SpaceX fairing test video from the Plum Brook facility indicate in any way that cables would work like this in a freefall/zero-g environment.   It's nice to imagine in our gravitationally conditioned minds {....}
It's accelerating, not free falling, so you are wrong here. However force is probably not 1g so it would behave differently, but I don't know why much differently.

It's too easy to think of this problem like a household vacuum cord automatically winding itself back inside the appliance housing, but it just won't work like that.  Each pull of the cord/cable on attached fairing halves will accelerate the halves in the direction of the pull.   Unless the vector of that acceleration exactly moves the halves to a rendezvous, they will impact obliquely, & spin apart from each other from an in-elastic collision, and not rendezvous.   Furthermore, once they are accelerating towards each other, cables cant slow them down.   Ever try making compression forces with a string?  That means RCS and sensors, and you may as well eliminate the cables entirely.   I see a a big tangled mass of cable and fairing resulting after a few collisions together.

1) They won't spin apart because they will be hold together by the very cable we talk about. That's the reason why IMO it could make sense - there I s no docking mechanism.

2) "Each pull will..." Sure it will. So you have 8 points to attach force. Quite a control system. It's not complicated to simulate it in software. Of course much harder to make it working in this simulation. But I believe it's software problem how to bring them back together gently.

3) "Can't slow them down." That's why you do it gently. Like shuttle landing. Once it was over airfield you could not move it up and try again. I don't see it as no go.

Title: Re: Fairing reuse
Post by: Ohsin on 04/10/2016 11:08 am
So at the moment they are looking to recover one half if I am right. But lets say in future after all experience gained they are recovering both halves, if recovery of one half goes wonky would that make other piece useless? Or these halves are designed to be swap-able?
Title: Re: Fairing reuse
Post by: cambrianera on 04/10/2016 12:11 pm
So at the moment they are looking to recover one half if I am right. But lets say in future after all experience gained they are recovering both halves, if recovery of one half goes wonky would that make other piece useless? Or these halves are designed to be swap-able?
Halves are manufactured separately (not single piece fairing cut in half) on computer controlled machinery.
Likely swappable.
Title: Re: Fairing reuse
Post by: Jim on 04/10/2016 12:23 pm
It's always super easy to claim "no it's impossible". But that's rarely true. That would be too hard, or that would not be cost effective, or that could be dangerous/not reliable because of... that I could believe.

"too hard, or that would not be cost effective, or that could be dangerous/not reliable because of." equates to "it's impossible"
Title: Re: Fairing reuse
Post by: Jim on 04/10/2016 12:29 pm

2) "Each pull will..." Sure it will. So you have 8 points to attach force. Quite a control system. It's not complicated to simulate it in software. Of course much harder to make it working in this simulation. But I believe it's software problem how to bring them back together gently.

3) "Can't slow them down." That's why you do it gently. Like shuttle landing. Once it was over airfield you could not move it up and try again. I don't see it as no go.


No, it is not a software problem. Cables are inadequate in that they can not provide 6 DOF control, since the only other anchor is the other fairing..   They will not prevent the fairing from twisting or hitting each other. There still are aero loads at separation.
Title: Re: Fairing reuse
Post by: Jim on 04/10/2016 12:32 pm
 
Or you claim that TOWs (thanks tyrred - I was lazy) weren't working because there is no cable which could easily withstand rocket exhaust?

Not relevant example.  Those cables weren't hundreds of miles long.  Also, the two TOW exhausts are angled way from the center line
Title: Re: Fairing reuse
Post by: Kaputnik on 04/10/2016 12:48 pm
You know, if it would be possible to hinge the damn thing, why not simply hinge it along one long edge? Then it could open along that edge and tumble away still connected.
If you push a long edge hinged fairing over the other long edge, you get an inward movement of the hinge.
You can add a reaction beam to keep the hinge clear from the payload, but this would increase the mass of the fairing.
(http://forum.nasaspaceflight.com/index.php?action=dlattach;topic=37727.0;attach=1106960)


Is it just me or does that looks rather Rogallo-esque? Hmmm...
Title: Re: Fairing reuse
Post by: llanitedave on 04/10/2016 03:23 pm

And how to keep them connected? Well, I see on the video were they test separation mechanism that both parts are connected, so it seems possible. And in old days there were those rockets controlled by cables, so there are things which can survive and do the job.


not true on either point.  The cables would put loads on the fairings and there is no way to bring them together in a controlled matter without them slamming together.

Which rockets were controlled by cables?

Of course that they would put loads, and so? This load would be symetric, fairings would be tiny bit heavier.
No way to bring them together? You mean that it's impossible to control  force required to pull the cable? Or you say that using force in only one way it's not possible to gently stop momentum? Like for example on rocket falling from the sky? Or you claim that TOWs (thanks tyrred - I was lazy) weren't working because there is no cable which could easily withstand rocket exhaust?

It's always super easy to claim "no it's impossible". But that's rarely true. That would be too hard, or that would not be cost effective, or that could be dangerous/not reliable because of... that I could believe.


How about "it's simply unnecessary."

Could you then please explain me what is necessary? I could believe that all is really required it's to reduce speed of impact with water. Pieces found are already quite large, so it would be believable.
Can you then help me and explain what for are those tests with controlling them? What could it help?


I've suggested a small parachute.  That and maybe a couple of small aerodynamic surfaces to add a bit of stability.  Don't see the need for much else.
Title: Re: Fairing reuse
Post by: Radical_Ignorant on 04/10/2016 06:00 pm

2) "Each pull will..." Sure it will. So you have 8 points to attach force. Quite a control system. It's not complicated to simulate it in software. Of course much harder to make it working in this simulation. But I believe it's software problem how to bring them back together gently.

3) "Can't slow them down." That's why you do it gently. Like shuttle landing. Once it was over airfield you could not move it up and try again. I don't see it as no go.


No, it is not a software problem. Cables are inadequate in that they can not provide 6 DOF control, since the only other anchor is the other fairing..   They will not prevent the fairing from twisting or hitting each other. There still are aero loads at separation.

Since there are four points of attachments on each fairing half it's easy to control twisting. You know how long is each cable. As well as it's easy to measure pressure on the cable. If one is longer that means it should be pulled little bit faster than other ones.

No 6DOF control? Why you need that?

I doubt now we talk about the same they thing? Why should they prevent fairing halves from hitting each other? It's all about hitting each other in controlled manner to reconnect and make shape which is safe in atmospheric heat and can be easily make floatable.

Sorry for lacking animation skill.

I see there two problems, which no one mentioned.
1) cables can touch payload or rocket in initial phase
2) it makes no difference really - it's all just about making it hit water little slower, atmospheric part makes no harm for them in current state or half fairing are good and stable enough lifting body and it's just enough to attach small parachutes to them and stabilize their rotation for a moment of launching it?
Title: Re: Fairing reuse
Post by: S.Paulissen on 04/10/2016 08:15 pm
It just seems the simplest solution would be to put a 'light' TPS on the outer surface of the fairing and stabilize the reentry orientation with an inflatable drag augmentation device (al la NASA's low density supersonic decelerator)  and eat the mass penalty by throwing performance at it. 

I seriously doubt they'll go much further down the fairing recovery road until they have enough excess performance to make the more error resistant plan work (i.e. keep sep nearly identical to current practice, then add steps later to reduce risk).
Title: Re: Fairing reuse
Post by: Jim on 04/11/2016 01:58 pm
Since there are four points of attachments on each fairing half it's easy to control twisting. You know how long is each cable. As well as it's easy to measure pressure on the cable. If one is longer that means it should be pulled little bit faster than other ones.

No 6DOF control? Why you need that?

I doubt now we talk about the same they thing? Why should they prevent fairing halves from hitting each other? It's all about hitting each other in controlled manner to reconnect and make shape which is safe in atmospheric heat and can be easily make floatable.



there is no "hitting" of the fairing halves.  they would get damaged.  Fairing mate is a slow and controlled motion.

What four attach points?

6DOF is needed because the cables are going to be tens of feet long and the fairing halves are going to be subject to aero and plume loads which will give them different rotation and translation rates.  They are not going to remain "collinear"  . The cables will be long enough to get twisted or have the fairings halves contact each other in weird attitudes


Title: Re: Fairing reuse
Post by: JamesH65 on 04/11/2016 02:19 pm
I'm still not sure why people want to bring the fairing back together. Why not just attempt to land each half individually. It's going to act more like a leaf when still in halves, rather than a bullet when recombined, which should mean an overall less stressful reentry.
Title: Re: Fairing reuse
Post by: Remes on 04/11/2016 10:46 pm
I found the comment in the after launch press conference from EM interesting (at 33:33): Each of the fairing halfs cost several millions.

Playing around with numbers: if each fairing half is 2mio (lower boundary), then the complete fairing is 4 mio. If I take 4mio per engine as an absolute upper boundary (then 10 engines would be 40mio, fairing 4 million and leaving 16mio for everything else including launch, testing and perhaps profit), then one fairing would equal the cost of one engine. Which seems somehow odd, given the complexity of an engine. And I would rather guess an engine is less then 4mio (because 16mio for everything else is not too much).
Title: Re: Fairing reuse
Post by: envy887 on 04/11/2016 11:18 pm
For a low temperature, low stress re-entry it helps to increase area, reduce mass, and increase drag coefficient.

Orienting halves individually with the concave side forward helps with all those.
Title: Re: Fairing reuse
Post by: georgegassaway on 04/11/2016 11:34 pm

BALLUTE
Title: Re: Fairing reuse
Post by: hrissan on 04/12/2016 04:17 pm
Each half should land independently, that's clear.

Here is how: each half has large parts of each on hinges, so it splits open, obtaining the shape of maple seed, then splashes down into water on autorotation!!! :):):)
Title: Re: Fairing reuse
Post by: Doesitfloat on 04/12/2016 04:48 pm

BALLUTE

Don't be silly that could be lightweight and practical. :)

Then when they are lower... just catch em

https://www.youtube.com/watch?v=XxFZ-VStApo
Title: Re: Fairing reuse
Post by: wannamoonbase on 04/12/2016 05:59 pm
I found the comment in the after launch press conference from EM interesting (at 33:33): Each of the fairing halfs cost several millions.

Playing around with numbers: if each fairing half is 2mio (lower boundary), then the complete fairing is 4 mio. If I take 4mio per engine as an absolute upper boundary (then 10 engines would be 40mio, fairing 4 million and leaving 16mio for everything else including launch, testing and perhaps profit), then one fairing would equal the cost of one engine. Which seems somehow odd, given the complexity of an engine. And I would rather guess an engine is less then 4mio (because 16mio for everything else is not too much).

The engines are a volume production product and could be getting cheaper with each one produced.  Depending on material costs.  SpaceX should be getting smarter and more efficient as they continue to crank out these engines, plus development costs get spread out more with each one made.

Fairings are a large structure, lower volume, hard to make, hard to handle, hard to ship. 

I can see the fairings as being more expensive than a single Merlin 1D.

Re-use will put additional pressure on competitors.
Title: Re: Fairing reuse
Post by: rds100 on 04/12/2016 06:15 pm

They should just learn how to build these cheaper, say some sort of 3D printing. Nowadays even large structures can be 3D printed.

Title: Re: Fairing reuse
Post by: Kaputnik on 04/12/2016 07:18 pm

They should just learn how to build these cheaper, say some sort of 3D printing. Nowadays even large structures can be 3D printed.



Composite materials get their strength from the use of (long) directional fibres.
3D printing isn't the answer to everything...
Title: Re: Fairing reuse
Post by: iamlucky13 on 04/12/2016 08:41 pm
3-D printing is massively over-hyped in the pop-science world. It has a growing, but still small place in the real engineering world, primarily for relatively complex shapes with low tolerances made in low volumes of single materials. 3-D printing as the most people recognize it is not suited for producing rocket fairings.

That said, there is a 3-D printing-like technology for carbon fiber (actually, a couple, but the types that extrude short-fiber+binder mixes like a regular 3-D printer are far from optimal strength or production rate wise): The NASA ISAAC robot definitely can do carbon fiber structure layup on this scale, when combined with rotating tooling. It's a variation of the same technology that produces the 787 fuselage sections. A larger custom gantry machine could do it with static tooling. SpaceX is well aware of this technology.

That only produces the uncured laminate, however. A single step would have been automated. That reduces the labor cost for that step somewhat, but whether it is enough to justify the up-front cost of the robot and more complex tooling is for SpaceX to figure out based on required production rates.

It still requires curing, trimming, stiffener and bracket installation, acoustic panel installation, and systems installation, including the latches and separation pushers, which themselves are relatively expensive parts.

I might as well also point out that SpaceX said a year or two ago that as they transition to higher production rates, they are doing work to streamline production throughout the factory, and part of the result of that should be lower production costs, but the fairings will remain a relatively significant cost that re-use could potentially lessen.
Title: Re: Fairing reuse
Post by: Robotbeat on 04/15/2016 09:28 pm

They should just learn how to build these cheaper, say some sort of 3D printing. Nowadays even large structures can be 3D printed.



Composite materials get their strength from the use of (long) directional fibres.
3D printing isn't the answer to everything...
The relevant tech here would be an automated fiber layup machine like is used for airplanes. It's still technically "Additive Manufacturing," so it's a kind of 3d printing except it uses a mandrel.

Still, SpaceX is better off trying reuse. They need to get good at this sort of thing anyway.

EDIT: Yes, the ISAAC machine. But these kind of machines are actually much better understood and more effectively utilized in industry than at NASA, to be absolutely honest. ISAAC is kind of a "me too!" sort of development, not anything ground-breaking (except in the literal sense since they need to reinforce the floor).
Title: Re: Fairing reuse
Post by: Space Ghost 1962 on 04/15/2016 10:46 pm

They should just learn how to build these cheaper, say some sort of 3D printing. Nowadays even large structures can be 3D printed.



Composite materials get their strength from the use of (long) directional fibres.
3D printing isn't the answer to everything...

6 months ago I was listening to a presentation on 3D printing composite materials for space/LV application, where they were laying down fibers with long range orientation/registration/no kinks/no twist. (They are thinking about forming them like "pre-stressed" concrete beams, with a programmed distribution of fiber characteristics so as to make structural parts that are otherwise impossible to fabricate any other way ...
Title: Re: Fairing reuse
Post by: cambrianera on 04/18/2016 07:47 pm
This is how fairing flaps can behave/deploy.
Obviously really simplified  ;)
Title: Re: Fairing reuse
Post by: sanman on 04/19/2016 06:04 am
This is how the professionals do it - the clamshell way:

https://www.youtube.com/watch?v=4FTB8TgvgUk

(http://www.stopelonmusk.org/tumblr_m90ka7Zr021rby5xwo1_500.jpg)
Title: Re: Fairing reuse
Post by: Blackjax on 04/23/2016 06:36 pm

In this post
https://forum.nasaspaceflight.com/index.php?topic=39181.msg1521556#msg1521556

...an idea gets laid out that the F9 might be relegated to more mid-sized payloads well inside its performance envelope once the FH is flying regularly and that this might leave reserve capacity for RTLS.  If you take this idea and run with it on the fairing front, what you might end up with is an improved mass budget for a redesigned & reusable fairing flying on a sandbagged F9 or a FH (which is otherwise overkill for most payloads that the market might produce in the foreseeable future).  Consider also that a redesigned fairing does not need to be optimized for shipping considerations the same way that an expendable would, because shipping logistics complexity and cost are amortized over many flights and you are shipping much fewer of them.

I have often wondered if the point of the FH isn't to loft big payloads, but to enable a combined F9/FH reusable fleet to shift mass margins across the existing market for payloads to maximize reusability and "aircraft like operations".
Title: Re: Fairing reuse
Post by: rds100 on 04/23/2016 07:19 pm

 Consider also that a redesigned fairing does not need to be optimized for shipping considerations the same way that an expendable would, because shipping logistics complexity and cost are amortized over many flights and you are shipping much fewer of them.


Am imissing something here? A reused fairing would need to be shipped many times, since it wouldn't return to the launch site, it would end somewhere in the ocean. Then it need to be retrieved, brought to land, transported by road, etc.


Title: Re: Fairing reuse
Post by: launchwatcher on 04/23/2016 07:29 pm

 Consider also that a redesigned fairing does not need to be optimized for shipping considerations the same way that an expendable would, because shipping logistics complexity and cost are amortized over many flights and you are shipping much fewer of them.


Am imissing something here? A reused fairing would need to be shipped many times, since it wouldn't return to the launch site, it would end somewhere in the ocean. Then it need to be retrieved, brought to land, transported by road, etc.
Short-distance road transport of oversized items from Port Canaveral to various launch pads at the Cape is clearly a solved problem.   



Title: Re: Fairing reuse
Post by: iamlucky13 on 04/27/2016 07:06 pm
The relevant tech here would be an automated fiber layup machine like is used for airplanes. It's still technically "Additive Manufacturing," so it's a kind of 3d printing except it uses a mandrel.

Still, SpaceX is better off trying reuse. They need to get good at this sort of thing anyway.

EDIT: Yes, the ISAAC machine. But these kind of machines are actually much better understood and more effectively utilized in industry than at NASA, to be absolutely honest. ISAAC is kind of a "me too!" sort of development, not anything ground-breaking (except in the literal sense since they need to reinforce the floor).

There might be a bit of "me-too" involved in the decision making to purchase ISAAC, but the stated intent is to allow NASA to prototype structures more easily.

It's somewhat surprising how much work is still going on within the aerospace industry just characterizing the performance of different layup patterns. I have a friend who recently left his aerospace engineering job in part because he was looking for more variety than continuously iterating small variations in fiber orientation, ply thickness, etc, analyzing their strength in various load cases, then sending along the better patterns to the test engineers to fabricate samples of to test and compare to the analysis. He spent several years doing this.

I presume NASA tends to work with different fibers and resins than the aircraft industry, and certainly different part shapes, so they may well have their own justification for on-site prototyping, such as for subscale or truncated fairing and interstage pieces or stiffeners for SLS. Fairings or interstages have large axial loads, but less significant pressure and bending loads. Aircraft fuselages have large pressure and bending loads, but relatively little axial loading, so what is optimal for aircraft is not what is optimal for rockets. I suppose from NASA's point of view, they'll pay for that optimization one way or another: either their suppliers figure it out and factor the development costs into what they charge, or NASA figures it out and shares the data with suppliers and the whole industry benefits.


6 months ago I was listening to a presentation on 3D printing composite materials for space/LV application, where they were laying down fibers with long range orientation/registration/no kinks/no twist. (They are thinking about forming them like "pre-stressed" concrete beams, with a programmed distribution of fiber characteristics so as to make structural parts that are otherwise impossible to fabricate any other way ...

That's automated fiber placement (AFP), like ISAAC. I believe it, or at least automated tape laying (ATL), started to be used for medium-sized aircraft structures in the 90's. NASA is not the only spaceflight organization starting to look at AFP.

It is possible to fabricate large parts in other ways. Hand layup is still an option, but very tedious. Most hand layup is done with woven or stitched multi-directional fiber cloth. Larger pieces can be put down that way, which helps with production efficiency, but you have less ability to play with the fiber direction since the material you're working with has been woven or stitched with fibers in specific orientations relative to each other. Most machine layup is done with ribbon-like "tows", frequently 1/4 to 1/2 inch wide, or for low curvature parts, sometimes with "tape" 6+ inches wide. Each fiber can have its orientation chosen more or less how the engineer wants within the final structure.

As a result of how each company evaluates those trade offs, I know of different aircraft that have similar parts made in different ways (AFP vs. ATL vs. hand layup of multi-directional fibers). So although SpaceX has the option of investing in fiber placement for their fairings, don't assume that it's necessarily the best choice for what they're doing.
Title: Re: Fairing reuse
Post by: mme on 05/16/2016 04:31 am
https://twitter.com/elonmusk/status/732042627445460992 (https://twitter.com/elonmusk/status/732042627445460992)

Quote
Raket_Mand @bittdk
@elonmusk how did the recovery of the fairings go?

Quote
Elon Musk ‏@elonmusk  1h1 hour ago
@bittdk Better. Not there yet, but a solution is likely.
Title: Re: Fairing reuse
Post by: sevenperforce on 05/16/2016 12:46 pm
https://twitter.com/elonmusk/status/732042627445460992 (https://twitter.com/elonmusk/status/732042627445460992)

Quote
Raket_Mand @bittdk
@elonmusk how did the recovery of the fairings go?

Quote
Elon Musk ‏@elonmusk  1h1 hour ago
@bittdk Better. Not there yet, but a solution is likely.
Good to see an update on this.

With the current ballistic re-entry, what are the estimated damage ratios? Like, 40% re-entry and 60% ocean impact? Or flipped?
Title: Re: Fairing reuse
Post by: cscott on 05/16/2016 04:20 pm
We haven't seen any recovered fairing pieces come back on go searcher yet.  So I'd say 100% re-entry right now.  The re-entry damage is sufficient to destroy any chance of recovering locatable pieces at least.
Title: Re: Fairing reuse
Post by: RDMM2081 on 05/16/2016 04:39 pm
Sorry if this is too elementary of a question or if I missed it being asked or answered previously, but is there any indication if the fairing pieces have any GPS or beacon tracking capabilities yet?  This would assume that the recovery boat could at least check in the right location to find any pieces that did make it to the surface. 

edit: removed GPS, apparently off-the-shelf models "self-destruct" upon nearing anything resembling ICBM speeds/altitudes, also removed completely redundant link to old article after re-reading the thread.

Still seems to me like finding any pieces of currently designed fairing is the most informative path forward to inform any more advanced recovery options in the future after seeing what the pieces look like, just need to find some.
Title: Re: Fairing reuse
Post by: kevin-rf on 05/16/2016 07:53 pm
edit: removed GPS, apparently off-the-shelf models "self-destruct" upon nearing anything resembling ICBM speeds/altitudes, also removed completely redundant link to old article after re-reading the thread.

Self destruct??? More like become civilian off the shelf devices become inaccurate because they can not properly process the timing signals and arrive at the correct result. Once they slow down, like hitting terminal velocity or bobbing in the ocean, accuracy should be restored.
Title: Re: Fairing reuse
Post by: launchwatcher on 05/16/2016 08:44 pm
edit: removed GPS, apparently off-the-shelf models "self-destruct" upon nearing anything resembling ICBM speeds/altitudes, also removed completely redundant link to old article after re-reading the thread.

Self destruct??? More like become civilian off the shelf devices become inaccurate because they can not properly process the timing signals and arrive at the correct result. Once they slow down, like hitting terminal velocity or bobbing in the ocean, accuracy should be restored.
Commodity GPS receivers have hard-coded speed and altitude limits and will shut down if they see they're moving too fast and/or too high.   

See, for instance, http://support.spectracom.com/articles/FAQ/Why-are-there-altitude-and-velocity-limits-for-GPS-equipment

Receivers without the limits are subject to export controls to ensure they don't end up guiding ICBM's.
Title: Re: Fairing reuse
Post by: manoweb on 05/16/2016 09:41 pm
I believe SpaceX might have the permissions in place to use GPS units that are enabled to work in a "rocket" scenario.
Title: Re: Fairing reuse
Post by: RDMM2081 on 05/16/2016 09:54 pm
edit: removed GPS, apparently off-the-shelf models "self-destruct" upon nearing anything resembling ICBM speeds/altitudes, also removed completely redundant link to old article after re-reading the thread.

Self destruct??? More like become civilian off the shelf devices become inaccurate because they can not properly process the timing signals and arrive at the correct result. Once they slow down, like hitting terminal velocity or bobbing in the ocean, accuracy should be restored.
Commodity GPS receivers have hard-coded speed and altitude limits and will shut down if they see they're moving too fast and/or too high.   

See, for instance, http://support.spectracom.com/articles/FAQ/Why-are-there-altitude-and-velocity-limits-for-GPS-equipment

Receivers without the limits are subject to export controls to ensure they don't end up guiding ICBM's.

Yeah, shut down is probably a better way to phrase it than "self-destruct", and that is the "feature" I was referring to, sorry if that was overly dramatic...  Also, SpaceX probably does have access to the "military grade" receivers so GPS might still be an option, but definitely not as easy as gluing a Garmin inside the fairing and seeing what happens.  Some sort of transmitter beacon seems much more likely to me.  Assuming they are doing any tracking at all, but otherwise how would they find any fairing which did make it to the surface, either intact, or in large enough pieces to be found?
Title: Re: Fairing reuse
Post by: kevin-rf on 05/17/2016 01:28 am
Uuuuum... Radar, the range does track these things and they do know where they generally splashed. Add to that for a fairing to survive it's final speed will be slow enough that civilian gps systems will work. Impact will not be at mach 10.

Easiest solution, stick an iridium phone in each half and have it call home as soon as it splashed down. The phone will have gps. I don't know how fancy iridium phones are, but maybe they can write an app. Provide it a Twitter feed. Tweets like whoa, that was intense, and a shark just swam by. They did get a go pro back from one of the fairings.
Title: Re: Fairing reuse
Post by: kevin-rf on 05/17/2016 01:32 am
Also, a spaceX fairing has already washed ashore. It had a go pro in it, and they did post the video.
Title: Re: Fairing reuse
Post by: meekGee on 05/17/2016 08:55 am


Easiest solution, stick an iridium phone in each half and have it call home as soon as it splashed down. The phone will have gps.

Yeah, but who will make the call?

Aha! Trained dolphins!  On both ends of the call of course!  I can see it now!

Title: Re: Fairing reuse
Post by: JamesH65 on 05/17/2016 10:54 am
edit: removed GPS, apparently off-the-shelf models "self-destruct" upon nearing anything resembling ICBM speeds/altitudes, also removed completely redundant link to old article after re-reading the thread.

Self destruct??? More like become civilian off the shelf devices become inaccurate because they can not properly process the timing signals and arrive at the correct result. Once they slow down, like hitting terminal velocity or bobbing in the ocean, accuracy should be restored.
Commodity GPS receivers have hard-coded speed and altitude limits and will shut down if they see they're moving too fast and/or too high.   

See, for instance, http://support.spectracom.com/articles/FAQ/Why-are-there-altitude-and-velocity-limits-for-GPS-equipment

Receivers without the limits are subject to export controls to ensure they don't end up guiding ICBM's.

Yeah, shut down is probably a better way to phrase it than "self-destruct", and that is the "feature" I was referring to, sorry if that was overly dramatic...  Also, SpaceX probably does have access to the "military grade" receivers so GPS might still be an option, but definitely not as easy as gluing a Garmin inside the fairing and seeing what happens.  Some sort of transmitter beacon seems much more likely to me.  Assuming they are doing any tracking at all, but otherwise how would they find any fairing which did make it to the surface, either intact, or in large enough pieces to be found?

Even if they had no access to 'military' GPS (ie usable at all speeds and altitudes) hardware, they could always make their own high accuracy system. Already been done by a guy I used to work with.

http://www.aholme.co.uk/GPS/Main.htm

Title: Re: Fairing reuse
Post by: Jim on 05/17/2016 01:48 pm
but otherwise how would they find any fairing which did make it to the surface, either intact, or in large enough pieces to be found?

They see it floating.  If it sinks they don't care about it.
Title: Re: Fairing reuse
Post by: Nomadd on 05/17/2016 02:47 pm
Uuuuum... Radar, the range does track these things and they do know where they generally splashed. Add to that for a fairing to survive it's final speed will be slow enough that civilian gps systems will work. Impact will not be at mach 10.

Easiest solution, stick an iridium phone in each half and have it call home as soon as it splashed down. The phone will have gps.
No need for even that much. If it's OK with the Coast Guard, they can just stick an off the shelf EPIRB in them with some sort of custom trigger.
Title: Re: Fairing reuse
Post by: kevin-rf on 05/17/2016 03:11 pm
No need for even that much. If it's OK with the Coast Guard, they can just stick an off the shelf EPIRB in them with some sort of custom trigger.
Raised eyebrows. Like I said, several off the shelf tracking solutions exists. Miss using EPIRB is not one of them.

The simplest and most foolproof are devices that communicate with existing LEO networks (Orbcomm, Iridium) and just say here I am, over here... Besides, both Orbcomm and Iridium should have very good relations with SpaceX, maybe they will give them a discount.

Heck, Iridium is about to roll out an aircraft tracking service.

No need to invent anything, and the fairings are already coming down intact enough that people do find them from time to time.
Title: Re: Fairing reuse
Post by: kevin-rf on 05/17/2016 03:17 pm
Off the shelf: https://www.iridium.com/products/details/spidertracks-satellite-tracking

Quote
Spidertracks Satellite Tracking

Spidertracks is more than just a tracking system: as well as knowing exactly where people and valuable assets are at any moment in time, it can also tell you how they are. If something goes wrong, and the website loses contact with the spider device, the system will automatically send text and email alerts to the right people, including rescue services, within minutes of the accident occurring. Because the alert is generated by the system, it doesn’t rely on the device surviving an accident, so it will always be sent, enabling rescue services to locate the site quickly based on the last transmitted position. With Spidertracks, no one needs to be lost at sea, on land, or in the air again.

It combines a portable tracking unit, the Spider, with a web-based client interface, enabling users to access their flight following and tracking details from anywhere at any time via the internet. Powered by a 10 V – 32 V power source, it has no external antenna and can be moved between aircraft or vehicles, so it doesn’t require expensive installation or certification. Partnered with Iridium, it offers global coverage.

Spidertracks also offers simple two-way global communication. Customers can send and receive texts with a compatible phone from anywhere on earth, via Iridium, through the Spidertracks website—ideal for anyone who needs to communicate from a remote region without GSM/cellphone coverage.

The unit is portable, with the tracks accessed from any internet connected device, and it is AFF compliant, offering a cost-effective, simple and reliable tracking-based safety system for anyone working or traveling in remote locations or risky situations.

Problem solved. Though, adding a smoke generator and disco lights would be a nice touch.
Title: Re: Fairing reuse
Post by: RDMM2081 on 05/17/2016 03:44 pm
but otherwise how would they find any fairing which did make it to the surface, either intact, or in large enough pieces to be found?

They see it floating.  If it sinks they don't care about it.
Uuuuum... Radar, the range does track these things and they do know where they generally splashed. Add to that for a fairing to survive it's final speed will be slow enough that civilian gps systems will work. Impact will not be at mach 10.

Easiest solution, stick an iridium phone in each half and have it call home as soon as it splashed down. The phone will have gps. I don't know how fancy iridium phones are, but maybe they can write an app. Provide it a Twitter feed. Tweets like whoa, that was intense, and a shark just swam by. They did get a go pro back from one of the fairings.

If all the following are true, then what has stopped them before?

1)  SpaceX are and have been interested in fairing recovery
2)  The fairing's are trackable via range radar
3)  One landed intact enough to float to shore

Was the Bahamas fairing making it to shore unclaimed a case where they were simply not interested in tracking it down and attempting recovery?  Or is it harder to find a fairing based only off a "last known position" obtained via range radar and then some hours later when they arrive at the spot, it's not there?  Oceans are big.

I think if the fairings/pieces are making it to the water, SpaceX needs a slightly better method for tracking them down and finding them.  GPS seems doable, but a beacon also seems like a good way to zero in on a spot if you have a ballpark area to start looking (range radar tracking will get you there apparently). 

The other opinion of mine I will toss out there is that they are, can, should, and will continue to experiment with RSC thrusters and start adding deployable control surfaces to help the fairings make it to the surface, in order to be tracked and then recovered.  I am not a fan of any of the "clamshell" or "reassembly" methods described upthread.  I do like the direction of the inflatable recovery mods, either ballooning, ballistic spinup, or just a flotation assist to keep the pieces from sinking.
Title: Re: Fairing reuse
Post by: cscott on 05/17/2016 04:25 pm
Go Searcher, which we believe to be the fairing recovery ship, has only gone out on the last few (three?) missions.  The washed-ashore fairings were well before that, likely before the fairing recovery program was begin in earnest.  In fact, it may have been those serendipitous discoveries which encouraged them to accelerate fairing recovery.

The fact that two fairing pieces made it to the surface intact doesn't mean they all are doing so.  There may have been luck involved.  Further, they are now experimenting with active recovery mechanisms; it is possible that failures in the active control are leading to worse outcomes (at this early point) than the passive fairings.  It's also possible that Go Searcher's primary role is to capture telemetry from the fairing, and actual recovery of pieces is not a priority.

Lastly, the ocean is a very big place.  They may well have trackers on board, but if the re-entry disables the trackers or tears them loose, Go Searcher might not be able to easily locate any remaining scraps even if they did make it to the surface.  If they know that the pieces they are interested in tend to sink after X hours, then they might not even attempt to rendezvous with any piece further than X hours travel away, so there could be luck in the prelaunch positioning of Go Searcher as well.

So there are lots of possible reasons (and I'm sure others can contribute more) why Go Searcher is still returning empty-handed despite a few instances of large fragments of fairing washing up on shore.  I don't think SpaceX needs our advice on what style of tracker and/or trained dolphin they should be using.
Title: Re: Fairing reuse
Post by: spacenut on 05/17/2016 04:27 pm
How much would a parachute, beacon, and a flotation bag add to the weight/cost?  Also, how much would a recovery boat operational costs add.  All that subtracted from the cost of the fairing? 
Title: Re: Fairing reuse
Post by: Jim on 05/17/2016 04:29 pm
It's also possible that Go Searcher's primary role is to capture telemetry from the fairing, and actual recovery of pieces is not a priority.


There is no antenna on it.

The issues is knowing how the fairing is breaking up and placing cameras/"beacons" on the pieces. 
Title: Re: Fairing reuse
Post by: RDMM2081 on 05/17/2016 06:17 pm
Go Searcher, which we believe to be the fairing recovery ship, has only gone out on the last few (three?) missions.  The washed-ashore fairings were well before that, likely before the fairing recovery program was begin in earnest.  In fact, it may have been those serendipitous discoveries which encouraged them to accelerate fairing recovery.

The fact that two fairing pieces made it to the surface intact doesn't mean they all are doing so.  There may have been luck involved.  Further, they are now experimenting with active recovery mechanisms; it is possible that failures in the active control are leading to worse outcomes (at this early point) than the passive fairings.  It's also possible that Go Searcher's primary role is to capture telemetry from the fairing, and actual recovery of pieces is not a priority.

Lastly, the ocean is a very big place.  They may well have trackers on board, but if the re-entry disables the trackers or tears them loose, Go Searcher might not be able to easily locate any remaining scraps even if they did make it to the surface.  If they know that the pieces they are interested in tend to sink after X hours, then they might not even attempt to rendezvous with any piece further than X hours travel away, so there could be luck in the prelaunch positioning of Go Searcher as well.

So there are lots of possible reasons (and I'm sure others can contribute more) why Go Searcher is still returning empty-handed despite a few instances of large fragments of fairing washing up on shore.  I don't think SpaceX needs our advice on what style of tracker and/or trained dolphin they should be using.

Interesting theories (fravorite/relevant ideas bolded), thanks for the response.

Here's another idea from left field, is it possible there are any optical telescope resources on the Go Searcher which could resolve the fairings during the end of their flight rather than the shore based systems which obviously cant resolve the fairings with much clarity once they are 300+ miles downrange?
Title: Re: Fairing reuse
Post by: Jim on 05/17/2016 06:29 pm

Here's another idea from left field, is it possible there are any optical telescope resources on the Go Searcher which could resolve the fairings during the end of their flight rather than the shore based systems which obviously cant resolve the fairings with much clarity once they are 300+ miles downrange?

No, there is nothing on the boat, optical or RF.

http://forum.nasaspaceflight.com/index.php?topic=39766.msg1526042#msg1526042
Title: Re: Fairing reuse
Post by: RDMM2081 on 05/17/2016 06:47 pm

Here's another idea from left field, is it possible there are any optical telescope resources on the Go Searcher which could resolve the fairings during the end of their flight rather than the shore based systems which obviously cant resolve the fairings with much clarity once they are 300+ miles downrange?

No, there is nothing on the boat, optical or RF.

http://forum.nasaspaceflight.com/index.php?topic=39766.msg1526042#msg1526042

Thanks for clarifying that for me. 

Can/Should they look into adding that capability, or is it presumed that the shore based optics are sufficient for them to determine what is happening to the fairings after separation well enough to inform changes to their recovery strategies?
Title: Re: Fairing reuse
Post by: kevin-rf on 05/17/2016 09:02 pm
Thanks for clarifying that for me. 

Can/Should they look into adding that capability, or is it presumed that the shore based optics are sufficient for them to determine what is happening to the fairings after separation well enough to inform changes to their recovery strategies?
SpaceX when working on the Falcon recovery problem did at one point use recoverable data pods. If they wanted, they could do the same with the fairing.

They called them Talon Pods.
Title: Re: Fairing reuse
Post by: iamlucky13 on 05/18/2016 03:34 am
How much would a parachute, beacon, and a flotation bag add to the weight/cost?  Also, how much would a recovery boat operational costs add.  All that subtracted from the cost of the fairing? 

I'm guessing this is a bit larger than what each fairing half needs (similar size Ariane V fairing weighs 2675 kg), and it weighs 250 pounds. I'm guessing this model is static line deployed. SpaceX would need one that is mortar deployed, which will add a bit more weight. They may also need a drogue chute or ballute for stability in the upper atmosphere and initial slowing.
http://www.millsmanufacturing.com/products/cargo-parachutes/14-products/44-g-11-cargo-parachute-assembly

I'm not sure it will need a flotation bag. Most of the structure would be honeycomb, so the density should be low. I suppose bags could be used to help keep the fairing stable in the water.

I think it's generally assumed they use a cold gas thruster system to stabilize the fairing during entry. That has a weight penalty, too, but since they're already attempting re-entries, this is presumably already present. There may also be some additional TPS beyond what is normally needed for ascent.

I'm guessing all this plus integration to the fairing runs in the high 5 to low 6-figure range, not counting development costs.

It looks like offshore supply vessels like GO Searcher hire out for rates in the $10-15,000 per day range.
http://www.dnaindia.com/india/report-ongc-takes-charter-route-for-offshore-supply-vessels-1994093

So recovery costs in the 1/4 to 1/2 million dollar range don't seem inconceivable to me. There will be some refurbishment costs, too. I assume any TPS on the outside and acoustic lining on the inside will be likely places for damage. Obviously salt water exposure means a good cleaning and inspection, testing, or replacement of any parts that could corrode or be fouled by salt precipitation. My wild guesstimating leads me to think total recovery and refurbishment costs would be in the 1/2 to 1 million dollar range.

Musk's prior comment was that fairings cost "several" million dollars.
Title: Re: Fairing reuse
Post by: Spidertracks on 05/18/2016 04:54 am
Spidertracks here - We're happy to donate a Spider to see if this might work.

They weigh 160g and can be fed with 10-32vDC drawing 1A every two-mins so a small battery should keep it alive long enough.

We attached one to a weather balloon recently and sent it skywards and it managed to get as high as 104,000ft with the Spider tracking every two-mins. We were able to put the Spider coords into our GPS and go right to the device when back on the ground. Video here - https://www.youtube.com/watch?v=tOOQ47mUfF4 (https://www.youtube.com/watch?v=tOOQ47mUfF4)

But I'm also with Kevin, smoke would be a nice touch too.

Off the shelf: https://www.iridium.com/products/details/spidertracks-satellite-tracking

Quote
Spidertracks Satellite Tracking

Spidertracks is more than just a tracking system: as well as knowing exactly where people and valuable assets are at any moment in time, it can also tell you how they are. If something goes wrong, and the website loses contact with the spider device, the system will automatically send text and email alerts to the right people, including rescue services, within minutes of the accident occurring. Because the alert is generated by the system, it doesn’t rely on the device surviving an accident, so it will always be sent, enabling rescue services to locate the site quickly based on the last transmitted position. With Spidertracks, no one needs to be lost at sea, on land, or in the air again.

It combines a portable tracking unit, the Spider, with a web-based client interface, enabling users to access their flight following and tracking details from anywhere at any time via the internet. Powered by a 10 V – 32 V power source, it has no external antenna and can be moved between aircraft or vehicles, so it doesn’t require expensive installation or certification. Partnered with Iridium, it offers global coverage.

Spidertracks also offers simple two-way global communication. Customers can send and receive texts with a compatible phone from anywhere on earth, via Iridium, through the Spidertracks website—ideal for anyone who needs to communicate from a remote region without GSM/cellphone coverage.

The unit is portable, with the tracks accessed from any internet connected device, and it is AFF compliant, offering a cost-effective, simple and reliable tracking-based safety system for anyone working or traveling in remote locations or risky situations.

Problem solved. Though, adding a smoke generator and disco lights would be a nice touch.
Title: Re: Fairing reuse
Post by: kevin-rf on 05/18/2016 10:49 am
But no disco lights?
Title: Re: Fairing reuse
Post by: Hobbes-22 on 05/18/2016 05:24 pm

If all the following are true, then what has stopped them before?

1)  SpaceX are and have been interested in fairing recovery
2)  The fairing's are trackable via range radar
3)  One landed intact enough to float to shore

Was the Bahamas fairing making it to shore unclaimed a case where they were simply not interested in tracking it down and attempting recovery?

What would be the point in recovering scrap?
Title: Re: Fairing reuse
Post by: RDMM2081 on 05/18/2016 05:36 pm

If all the following are true, then what has stopped them before?

1)  SpaceX are and have been interested in fairing recovery
2)  The fairing's are trackable via range radar
3)  One landed intact enough to float to shore

Was the Bahamas fairing making it to shore unclaimed a case where they were simply not interested in tracking it down and attempting recovery?

What would be the point in recovering scrap?

Identify weak points in the fairing design, either to strengthen those points of failure, or modify their recovery system to avoid creating loads which lead to that type of failure.
Title: Re: Fairing reuse
Post by: Lar on 05/18/2016 05:58 pm
Spidertracks here - We're happy to donate a Spider to see if this might work.

I would think SpaceX doesn't need a donation, they have money... (but maybe you give them one for their use in exchange for featuring them in your adverts?)

Also I think lights are better than smoke, usually smoke from electronics is not a good sign :)

Also, welcome to the forums, what an awesome first post!!!!
Title: Re: Fairing reuse
Post by: Hobbes-22 on 05/18/2016 06:49 pm

If all the following are true, then what has stopped them before?

1)  SpaceX are and have been interested in fairing recovery
2)  The fairing's are trackable via range radar
3)  One landed intact enough to float to shore

Was the Bahamas fairing making it to shore unclaimed a case where they were simply not interested in tracking it down and attempting recovery?

What would be the point in recovering scrap?

Identify weak points in the fairing design, either to strengthen those points of failure, or modify their recovery system to avoid creating loads which lead to that type of failure.

Sure, that has value when they start adding a recovery system to the fairing. I had the impression the Bahamas fairing (and all fairings before that) didn't have any recovery system, so the only thing they'd learn from recovering those would be the amount of damage an unbraked sea impact does. That has limited usefulness in my opinion, so to answer your question, that's what stopped them before.
Title: Re: Fairing reuse
Post by: kevin-rf on 05/18/2016 07:13 pm
Sure, that has value when they start adding a recovery system to the fairing. I had the impression the Bahamas fairing (and all fairings before that) didn't have any recovery system, so the only thing they'd learn from recovering those would be the amount of damage an unbraked sea impact does. That has limited usefulness in my opinion, so to answer your question, that's what stopped them before.

Here is the odd thing about that. They attached a Go-Pro to it. A very odd thing to do if you have zero chance of getting it back. I wonder if they where hoping on an off chance of getting one back someday. And now one has washes ashore they are going, hmmm.....

I do think going from recovering a fairing to reflying it will be a stretch. You are going from a clean room environment to a swim and then have to clean it so it can again be used in a clean room. No saying it's impossible, but...
Title: Re: Fairing reuse
Post by: rickyramjet on 05/19/2016 04:01 am
Sure, that has value when they start adding a recovery system to the fairing. I had the impression the Bahamas fairing (and all fairings before that) didn't have any recovery system, so the only thing they'd learn from recovering those would be the amount of damage an unbraked sea impact does. That has limited usefulness in my opinion, so to answer your question, that's what stopped them before.

Here is the odd thing about that. They attached a Go-Pro to it. A very odd thing to do if you have zero chance of getting it back. I wonder if they where hoping on an off chance of getting one back someday. And now one has washes ashore they are going, hmmm.....

I do think going from recovering a fairing to reflying it will be a stretch. You are going from a clean room environment to a swim and then have to clean it so it can again be used in a clean room. No saying it's impossible, but...
I would have assumed there was live video being transmitted back to SpaceX, that they wouldn't have relied on random chance to provide them a video.  Also, the fairing was built in a non-clean room environment, so I see no problem reusing one after clean up.  Perhaps they hope to snatch the fairings before they reach the ocean with some type of mid-air retrieval, so no salt water contamination.
Title: Re: Fairing reuse
Post by: envy887 on 05/19/2016 02:06 pm
...
Perhaps they hope to snatch the fairings before they reach the ocean with some type of mid-air retrieval, so no salt water contamination.

This seems like the most reusability-friendly solution. Surviving re-entry is hard enough, no point in building it to survive impact with the ocean if they don't have to. A small chute, a long line, and a rather large helicopter should do. But first they have to get it down the lower atmosphere in one piece and track where it's going accurately enough to be there waiting.
Title: Re: Fairing reuse
Post by: LouScheffer on 05/19/2016 07:15 pm
You are going from a clean room environment to a swim and then have to clean it so it can again be used in a clean room. No saying it's impossible, but...
The people who work in a clean room do exactly this every day.  Plus people are harder to pressure-wash or steam clean than fairings.
Title: Re: Fairing reuse
Post by: Kaputnik on 05/19/2016 07:28 pm
...
Perhaps they hope to snatch the fairings before they reach the ocean with some type of mid-air retrieval, so no salt water contamination.

This seems like the most reusability-friendly solution. Surviving re-entry is hard enough, no point in building it to survive impact with the ocean if they don't have to. A small chute, a long line, and a rather large helicopter should do. But first they have to get it down the lower atmosphere in one piece and track where it's going accurately enough to be there waiting.

I don't have the numbers to hand... what is the downrange impact distance of the fairing? A big helicopter has a working radius of aronud 200nm so might not be enough to reach the area. Would this need a ship-based helicopter?
Title: Re: Fairing reuse
Post by: kevin-rf on 05/19/2016 08:23 pm
You are going from a clean room environment to a swim and then have to clean it so it can again be used in a clean room. No saying it's impossible, but...
The people who work in a clean room do exactly this every day.  Plus people are harder to pressure-wash or steam clean than fairings.
Never seen anyone pressure wash sound insulation like what is found inside a fairing... My point is that the fairing will be encasing something that has lived all it's life in a clean room. The inside of a fairing is not a solid hard surface that you can just apply some elbow grease to.
Title: Re: Fairing reuse
Post by: D_Dom on 05/19/2016 08:42 pm
Maybe, if you planned on R&R of the insulation? Nooks and Crannies could be avoided with sufficient detail design.
Title: Re: Fairing reuse
Post by: LouScheffer on 05/20/2016 12:17 am
You are going from a clean room environment to a swim and then have to clean it so it can again be used in a clean room. No saying it's impossible, but...
The people who work in a clean room do exactly this every day.  Plus people are harder to pressure-wash or steam clean than fairings.
Never seen anyone pressure wash sound insulation like what is found inside a fairing... My point is that the fairing will be encasing something that has lived all it's life in a clean room. The inside of a fairing is not a solid hard surface that you can just apply some elbow grease to.
Sound insulation is not very structurally strong, or heat resistant, or wind proof.  I would guess they would strip off the soft stuff, carefully wash and inspect the structural parts, then re-apply the soundproofing.  Most of the cost of the fairing has to be in the large composite pieces, not the sound insulation.
Title: Re: Fairing reuse
Post by: envy887 on 05/20/2016 12:21 am
...
Perhaps they hope to snatch the fairings before they reach the ocean with some type of mid-air retrieval, so no salt water contamination.

This seems like the most reusability-friendly solution. Surviving re-entry is hard enough, no point in building it to survive impact with the ocean if they don't have to. A small chute, a long line, and a rather large helicopter should do. But first they have to get it down the lower atmosphere in one piece and track where it's going accurately enough to be there waiting.

I don't have the numbers to hand... what is the downrange impact distance of the fairing? A big helicopter has a working radius of aronud 200nm so might not be enough to reach the area. Would this need a ship-based helicopter?

Or a barge based helo...
Title: Re: Fairing reuse
Post by: bioelectromechanic on 05/28/2016 09:49 am
Fairing sep earlier on this one?
Title: Re: Fairing reuse
Post by: southshore26 on 05/28/2016 01:23 pm
Didn't seem like it.
Title: Re: Fairing reuse
Post by: Silmfeanor on 06/02/2016 08:54 pm
https://twitter.com/elonmusk/status/738471747540783104 (https://twitter.com/elonmusk/status/738471747540783104)

in response to a question: Are RCS thrusters the sole component for fairing recovery? Are chutes required?

Quote
@mattyteare @karaswisher @waltmossberg @YouTube autosteering chutes will be added soon

So, we'll perhaps see some fairing halves coming back under chutes!
Title: Re: Fairing reuse
Post by: AncientU on 06/02/2016 09:07 pm
Soon!

Wonder how far a self-steering chute could travel from the top of the atmosphere?
Hundreds of miles??? Seems doubtful, but gliders do travel that far from few 10k ft releases.
Title: Re: Fairing reuse
Post by: bstrong on 06/02/2016 09:41 pm
A bit of googling on "autosteering chutes" turns up that there are some available from the folks who make the Dragon chutes that sound pretty close to their needs. I wasn't expecting this to be available off-the-shelf.

Quote
Nov 7/12: JPADS 10k. HDT Global subsidiary Airborne Systems announces that their “Dragonfly external link” JPADS 10K is in full rate production, with the first 243 type classified systems set to be delivered by April 2013.

The renamed JPADS 10K is the 2nd type classified JPADS platform to be fielded by the U.S. military. Unlike the lighter JPADS 2K’s 150m accuracy, the 10,000 pound capacity JPADS 10K is accurate only to within 250 meters. On the other hand, it can be used with Type V airdrop platforms to carry vehicles like Humvees, artillery pieces like an M777, or irregularly shaped items like shelters, generators, etc.

http://www.defenseindustrydaily.com/jpads-making-precision-airdrop-a-reality-0678/
Title: Re: Fairing reuse
Post by: Jim on 06/03/2016 01:26 am
Soon!

Wonder how far a self-steering chute could travel from the top of the atmosphere?
Hundreds of miles??? Seems doubtful, but gliders do travel that far from few 10k ft releases.

The chutes wouldn't come out until much lower in the atmosphere.  The ACS on the fairing is to keep it oriented until it is lower.
Title: Re: Fairing reuse
Post by: envy887 on 06/03/2016 02:05 am
Soon!

Wonder how far a self-steering chute could travel from the top of the atmosphere?
Hundreds of miles??? Seems doubtful, but gliders do travel that far from few 10k ft releases.

The chutes wouldn't come out until much lower in the atmosphere.  The ACS on the fairing is to keep it oriented until it is lower.

Gliders ride thermals to get that distance and have better glide ratios than chutes. Tens of miles is more likely. Think they will try to land it on a ship?
Title: Re: Fairing reuse
Post by: arsenal on 06/03/2016 06:52 am
Soon!

Wonder how far a self-steering chute could travel from the top of the atmosphere?
Hundreds of miles??? Seems doubtful, but gliders do travel that far from few 10k ft releases.

The chutes wouldn't come out until much lower in the atmosphere.  The ACS on the fairing is to keep it oriented until it is lower.

Gliders ride thermals to get that distance and have better glide ratios than chutes. Tens of miles is more likely. Think they will try to land it on a ship?
My guess would be similar to what they did with recovering the first stage. First they will pick a target in the ocean and see how close they can get to it. Additionally, this time they probably will send one of their boats try and recover it since unlike the first stage a fairing will probably stay in tact on impact with water. Then they may potentially try to land it on a ship, but I doubt it would be the same on that the first stage lands on. Pretty high chance that stuff collides.
Title: Re: Fairing reuse
Post by: Kaputnik on 06/03/2016 06:59 am
A mid-air capture by a helicopter would seem feasible, but a fairly expensive exercise- especially as you'd need two. But any other option means either splashing the fairing, or fitting (heavy) equipment to deal with impact. Plus I really doubt a steerable chute could have the accuracy to get it down onto a boat anyway.
Title: Re: Fairing reuse
Post by: savuporo on 06/03/2016 07:28 am
Plus I really doubt a steerable chute could have the accuracy to get it down onto a boat anyway.
Military precision airdrop steerable parafoils ( Atair, MMIST, SPADES, Zodiac etc) had accuracy of about 50-200 meters ~8 years ago. Depending on payload size and drop altitude of course. Not hitting a barge with that, but i guess military never had a land on a dime requirement.
Title: Re: Fairing reuse
Post by: envy887 on 06/03/2016 01:29 pm
Plus I really doubt a steerable chute could have the accuracy to get it down onto a boat anyway.
Military precision airdrop steerable parafoils ( Atair, MMIST, SPADES, Zodiac etc) had accuracy of about 50-200 meters ~8 years ago. Depending on payload size and drop altitude of course. Not hitting a barge with that, but i guess military never had a land on a dime requirement.
Maybe the boat can drive the last 50-100m to get under the fairing. It doesn't have to land on a droneship, since a fairing coming down under a chute isn't all that dangerous... mass in only ~2t, terminal velocity is probably a few m/s, and there's no explosives aboard. Land it on a airbag sitting on the deck.
Title: Re: Fairing reuse
Post by: Kaputnik on 06/03/2016 05:14 pm
Look up the old episode of Top Gear (UK) where they tried to land a stunt parachutist in the back seat of a convertible car. It took a whole day of filming before they got it right.

My bet is
A) splash the stage, write off the foam but reuse the composite structure.
B) Much less likely, snag it out of the air with a pair of helicopters. But replacing the foam might be cheaper.
Title: Re: Fairing reuse
Post by: Lar on 06/03/2016 05:20 pm
Look up the old episode of Top Gear (UK) where they tried to land a stunt parachutist in the back seat of a convertible car. It took a whole day of filming before they got it right.

My bet is
A) splash the stage, write off the foam but reuse the composite structure.
B) Much less likely, snag it out of the air with a pair of helicopters. But replacing the foam might be cheaper.

Er, splash the FAIRING... they tried the "splash the stage" thing already :)

As for the landing in a convertable, you don't really have x and y authority, all you can do is turn... with thrusters an ASDS like catcher could move in any desired direction.

I agree that replacing the foam is probably cheaper than helicopters ... especially because you have to figure out how to base them at sea since they don't have the range/loiter to fly out 500 nm, loiter around through a whole launch cycle and return.
Title: Re: Fairing reuse
Post by: AncientU on 06/03/2016 05:27 pm
Soon!

Wonder how far a self-steering chute could travel from the top of the atmosphere?
Hundreds of miles??? Seems doubtful, but gliders do travel that far from few 10k ft releases.

The chutes wouldn't come out until much lower in the atmosphere.  The ACS on the fairing is to keep it oriented until it is lower.

Understand using ACS to control orientation until it hits the top of the atmosphere, and control that part of the descent where parachutes are useless, but wondering how high the parachute could deploy and how far it could travel back toward land to see if it is possible to get back to within helecopter flight range of the launch site or where ever helos can fly from.
Title: Re: Fairing reuse
Post by: Chris_Pi on 06/03/2016 06:20 pm
Soon!

Wonder how far a self-steering chute could travel from the top of the atmosphere?
Hundreds of miles??? Seems doubtful, but gliders do travel that far from few 10k ft releases.

The chutes wouldn't come out until much lower in the atmosphere.  The ACS on the fairing is to keep it oriented until it is lower.

Understand using ACS to control orientation until it hits the top of the atmosphere, and control that part of the descent where parachutes are useless, but wondering how high the parachute could deploy and how far it could travel back toward land to see if it is possible to get back to within helecopter flight range of the launch site or where ever helos can fly from.

I was was thinking the same about the possibility for the fairing to fly itself back. It's already pretty light for it's size, Adding parachutes might be more for the steering than anything else. Paragliders https://en.wikipedia.org/wiki/Paragliding (https://en.wikipedia.org/wiki/Paragliding) can manage a 9:1-16:1 glide ratio. Get the parachutes open nice and high and a fairing could cover a whole lot of distance back towards land.
Title: Re: Fairing reuse
Post by: manoweb on 06/03/2016 06:24 pm
especially because you have to figure out how to base them at sea since they don't have the range/loiter to fly out 500 nm, loiter around through a whole launch cycle and return.

What was ULA's plan to recover the engines then?

Title: Re: Fairing reuse
Post by: Jim on 06/03/2016 06:44 pm
but wondering how high the parachute could deploy and how far it could travel back toward land to see if it is possible to get back to within helecopter flight range of the launch site or where ever helos can fly from.

It takes different chutes for different altitudes,  Chutes for landing are usually deployed low in the atmosphere, 10kft.  They have issues opening higher.  Drogues open around 50kft.  There isn't going to be a parafoil that will open at high altitudes.
Title: Re: Fairing reuse
Post by: envy887 on 06/03/2016 06:45 pm
especially because you have to figure out how to base them at sea since they don't have the range/loiter to fly out 500 nm, loiter around through a whole launch cycle and return.

What was ULA's plan to recover the engines then?

The Falcon 9 1st stage engines and thrust structure weigh more than 12,000 kg, and Vulcan would probably be heavier. Would need multiple choppers or a heavy airplane to catch that.
Title: Re: Fairing reuse
Post by: cambrianera on 06/03/2016 06:59 pm
especially because you have to figure out how to base them at sea since they don't have the range/loiter to fly out 500 nm, loiter around through a whole launch cycle and return.

What was ULA's plan to recover the engines then?

The Falcon 9 1st stage engines and thrust structure weigh more than 12,000 kg, and Vulcan would probably be heavier. Would need multiple choppers or a heavy airplane to catch that.
Nine M1D engines are about 4000 kg, octaweb and piping should be one ton.
Title: Re: Fairing reuse
Post by: Lar on 06/03/2016 07:01 pm
especially because you have to figure out how to base them at sea since they don't have the range/loiter to fly out 500 nm, loiter around through a whole launch cycle and return.

What was ULA's plan to recover the engines then?

The Falcon 9 1st stage engines and thrust structure weigh more than 12,000 kg, and Vulcan would probably be heavier. Would need multiple choppers or a heavy airplane to catch that.
We do have threads to cover SMART, probably should review those, IIRC some of these questions were answered... To this specific question I don't think the engines return nearly as far down range as a fairing does so it's within reach of a land based helo to get them.

Not sure this is the best thread but it's a start  http://forum.nasaspaceflight.com/index.php?topic=37777
This one also has a lot of good background and links to papers and presentations:  http://forum.nasaspaceflight.com/index.php?topic=38403
Title: Re: Fairing reuse
Post by: sewebster on 06/03/2016 08:20 pm
I agree that replacing the foam is probably cheaper than helicopters ... especially because you have to figure out how to base them at sea since they don't have the range/loiter to fly out 500 nm, loiter around through a whole launch cycle and return.

You can do in-air refueling of helicopters.

Basing them at sea.... whoa... I mean, we just figured out how to land a simple rocket on a ship, now suddenly you're talking about moving directly to something with huge spinning blades!
Title: Re: Fairing reuse
Post by: Robotbeat on 06/03/2016 08:25 pm
Or use an airplane to recover them. Doesn't have to be a helicopter. Corona used airplanes. Seems like it'd be cheaper, faster, maybe safer. Airplanes are lower maintenance, can cover a much longer range, and SpaceX already uses them sometimes just for observing the booster recovery attempts.

Once a fairing halve is caught by the plane, however, I'm not entirely sure how it'd be gently placed on the ground.
Title: Re: Fairing reuse
Post by: Lar on 06/03/2016 08:30 pm
I agree that replacing the foam is probably cheaper than helicopters ... especially because you have to figure out how to base them at sea since they don't have the range/loiter to fly out 500 nm, loiter around through a whole launch cycle and return.

You can do in-air refueling of helicopters.

Basing them at sea.... whoa... I mean, we just figured out how to land a simple rocket on a ship, now suddenly you're talking about moving directly to something with huge spinning blades!
SpaceX optimizes for cost. Are you sure that in-air refueling of not one, but two, helos is going to be the cheapest way? If not, are you sure that basing them on a ship is going to be the cheapest?
Title: Re: Fairing reuse
Post by: sewebster on 06/03/2016 08:43 pm
I agree that replacing the foam is probably cheaper than helicopters ... especially because you have to figure out how to base them at sea since they don't have the range/loiter to fly out 500 nm, loiter around through a whole launch cycle and return.

You can do in-air refueling of helicopters.

Basing them at sea.... whoa... I mean, we just figured out how to land a simple rocket on a ship, now suddenly you're talking about moving directly to something with huge spinning blades!
SpaceX optimizes for cost. Are you sure that in-air refueling of not one, but two, helos is going to be the cheapest way? If not, are you sure that basing them on a ship is going to be the cheapest?

Don't forget the other helicopters with high speed cameras live streaming to the public!

Yeah, sorry, my whole post was basically supposed to be sarcastic. And I realize you were actually advocating against the ship-based concept. Here's the translation of my post:

"Basing helicopters on ships is pretty much a solved problem if they wanted to go that way... but I'm guessing they will try to avoid something like that if at all possible to reduce costs.
Title: Re: Fairing reuse
Post by: arsenal on 06/03/2016 09:15 pm
Another factor is wind. Not sure how well the parachutes will be able to steer in heavy wind. There will probably be some severe restrictions to where you can aim the chutes based on the weather conditions.
Title: Re: Fairing reuse
Post by: Kaputnik on 06/03/2016 10:15 pm
Do we genuinely think that splashing the fairing halves is a no-go? They must be relatively sturdy to withstand aero loads, and are nowhere near the size/scale of a first stage.
Title: Re: Fairing reuse
Post by: manoweb on 06/03/2016 10:29 pm
Kaputnik, I was under the impression that the expensive part of the fairings, the composite, can survive a splash down and not be damaged by saltwater.
Title: Re: Fairing reuse
Post by: georgegassaway on 06/03/2016 10:53 pm
Or use an airplane to recover them. Doesn't have to be a helicopter. Corona used airplanes.
……
Once a fairing halve is caught by the plane, however, I'm not entirely sure how it'd be gently placed on the ground.

Fairings way too big and flimsy (once in separated halves) to use a plane.  Air-snag of satellites, they were around 3 feet diameter and very robust.

And even if they could survive, no way to land them gently as you noted (Discoverer/Coronas were winched inside of the open back section of a C-117 Flying Boxcar).

Another factor is wind. Not sure how well the parachutes will be able to steer in heavy wind. There will probably be some severe restrictions to where you can aim the chutes based on the weather conditions.

An airborne vehicle can “steer” fine once it is off the ground and into the air.  Wind direction and velocity is not a factor for steering.  Severe turbulence can be.

Keep in mind for example that if a hot air balloon is a few hundred feet up flying in 10 mph wind, from the perspective of those on board, the balloon is in calm air, while the ground is moving at 10 mph.

One good thing is that over the ocean there does not tend to be as much turbulence as occurs over land due to trees, buildings, mountains, and thermal activity from uneven heating of the ground.

With a smart enough autonomous steering system for chutes, it could turn into the wind to use a headwind for a slower landing into the water.  Say if a 30 mph glide speed and 15 mph wind, fly into the wind for a net 15 mph horizontal velocity (which of course human parachutists do, usually with some nearby wind direction indicator such as windsock or smoke canister).  There are various means that it could use to determine the wind direction while over the water, such as comparing the  GPS based horizontal velocity and  with the indicated airspeed, while in a wide circle (or flying a rounded-square pattern) to derive the likely wind direction and speed.

I am not saying I think landing by chute into the water is how they’d do it vs say grabbing in midair by helicopter.  Just noting that an airplane type of air-snag seems unfeasible, and that in the most basic sense wind does NOT make it harder to steer (Landing during a very serious storm, that would be a different issue, as that would be a problem for any system.  Any air-snag during a storm, a risk of mid-air collision and loss of crew. ).  If K.I.S.S. rules, then chutes into water would seem the most practical. Unless there's a really big reason why salt-water landing is not good even though they are mostly composite (since they are not 100.00% composite, possibly some critical not-practical-to-replace components might be affected)

However, I just got to thinking about the aerodynamic interaction of  steerable chutes and the relatively lightweight  very large fairings.   I would hope that the suspension lines would put the fairing at a horizontal or near horizontal angle, in such a way that the rear edges of the fairing would act like rudders to keep the fairing pointed into the wind. Otherwise might need a little tail chute at the back of the fairing to keep the nose pointed into the airflow, as often used with long-distance helicopter transport of cargo to keep it from spinning around.
Title: Re: Fairing reuse
Post by: DAZ on 06/03/2016 11:05 pm
You can probably can get between a 4/1 to 8/1 glide ratio off the parachutes.  It really depends on how much weight you want to use for the parachutes.  The other downside to a better glide ratio, other than weight, is the ability to glide into the wind.  If the wind is too high for the glide ratio you might actually be going backwards.  Although it is probably the most desirable to glide all the way back to the ship probably the best reason to have them glide is so they can meet at the same known points for recovery.

So depending on deployment height/winds they could possibly glide for as little as 4 miles with a 4/1 and deployment at 5000 feet.  If deployed at 35,000 to 45,000 feet you could possibly get between 25 and 50 miles.  You could definitely employ them higher than this but it might not gain you as much as you might think.  The glide ratios at let’s say 80,000 feet might be closer to 1/1 and would leave them subjected to high-altitude wind’s.  It might be better to get through these wind’s faster than trying to glide through them.

It has got to be cheaper, not to mention less costly, to try to find and recover 2 mostly submerged/bobbing fairings a quarter-mile from each other (at a predetermined known location) than to try to find those same fairings someplace within 100 square miles separated by something like 50 miles of ocean.

I really don’t see how the fairings can be so damaged by a little immersion in salt water that it could possibly justify the cost of a helicopter recovery.  And really what you’re talking about here is 2 long-range helicopters.  Most of the parts should be safe from a little salt water immersion, they would just get rinsed off once they’re on board the ship.  The few parts that absolutely can’t be made to tolerate the salt water have just got to be cheaper to be replaced than the cost of a helicopter recovery.
Title: Re: Fairing reuse
Post by: friendly3 on 06/04/2016 01:12 am
The few parts that absolutely can’t be made to tolerate the salt water have just got to be cheaper to be replaced than the cost of a helicopter recovery.

No, the few parts that absolutely can’t be made to tolerate the salt water and the cost of a boat recovery have just got to be cheaper to be replaced than the cost of a helicopter recovery.
Title: Re: Fairing reuse
Post by: oiorionsbelt on 06/04/2016 01:18 am
Seems as though ya just need to get them down rather gently and pick em up rather quickly.
Title: Re: Fairing reuse
Post by: tleski on 06/04/2016 03:06 am
Seems as though ya just need to get them down rather gently and pick em up rather quickly.

I think the first photo (the one with the flag) shows a fragment of the interstage, not fairing.
Title: Re: Fairing reuse
Post by: CJ on 06/04/2016 03:28 am
Something to bear in mind regarding helicopters (or planes, for that matter); range does not mean the same thing for military craft as it does for civilian. The military definition is usually out and back, whereas the civilian is one-way.

Another factor with helicopters; is they are carrying their cargo underslung (outside), range will be significantly decreased over carrying it internal.

Here's an article of how NASA tried to do a mid-air retrieval, via helicopter, of the Genisis probe.  (that's the one that crashed due to chute failure). http://www.space.com/281-sky-capture-nasa-bring-genesis-earth.html

So, seeing as how the fairings would tend to come down not too far (50 miles?) from the ASDS on non-boostback-burn missions, I wonder if it's feasible to use the ASDS as a launch point for the helicopters; they ride out on the ASDS, take off a few minutes before launch, snag the fairings, and lower them to either the support ship or ASDS deck. (I strongly suspect the former.) and then fly to shore.  You'd need helicopters with longer than normal range (some have that kind of range, and others can have an extra fuel tank added). I think the timing would be pretty daunting, so perhaps it'd be better (also from a cost perspective, perhaps) to emulate what the Air Force did way back in 1960 and after; use a cargo plane. 
Title: Re: Fairing reuse
Post by: Comga on 06/04/2016 04:20 am
(snip)
So, seeing as how the fairings would tend to come down not too far (50 miles?) from the ASDS on non-boostback-burn missions, I wonder if it's feasible to use the ASDS as a launch point for the helicopters; they ride out on the ASDS, take off a few minutes before launch, snag the fairings, and lower them to either the support ship or ASDS deck. (I strongly suspect the former.) and then fly to shore.  You'd need helicopters with longer than normal range (some have that kind of range, and others can have an extra fuel tank added). I think the timing would be pretty daunting, so perhaps it'd be better (also from a cost perspective, perhaps) to emulate what the Air Force did way back in 1960 and after; use a cargo plane. 

At the risk of going farther down the rabbit hole....
A big problem with staging helicopters from the ASDS is what happens if they fail to take off?  They would have people and a helicopter on the ASDS. That would probably mean calling off the booster recovery.
Title: Re: Fairing reuse
Post by: The Amazing Catstronaut on 06/04/2016 04:55 am
Salt water isn't really good for anything metallic (see STS SRBs), but helicopters cut into the fairing reuse cost. Are we completely sure that helicopter recovery is what they intend to do? Are there any alternative methods for ensuring the fairing doesn't end up in the drink?

Edit: If air recovery truly is the way to go, a fixed winged aircraft does indeed seem preferable. Helicopters are not fun to fly far over water notwithstanding. A pity there isn't a sufficiently large drone.
Title: Re: Fairing reuse
Post by: IntoTheVoid on 06/04/2016 05:29 am
Why not just use JPADS and land the fairings on their own ASDS. The 10,000 lb version is already called DragonFly. Could be confusing, but their heart's in the right place.   ::)

https://en.wikipedia.org/wiki/Joint_Precision_Airdrop_System
http://www.militaryaerospace.com/articles/2014/04/computer-parachute-airdrop.html
Title: Re: Fairing reuse
Post by: CJ on 06/04/2016 05:31 am
(snip)
So, seeing as how the fairings would tend to come down not too far (50 miles?) from the ASDS on non-boostback-burn missions, I wonder if it's feasible to use the ASDS as a launch point for the helicopters; they ride out on the ASDS, take off a few minutes before launch, snag the fairings, and lower them to either the support ship or ASDS deck. (I strongly suspect the former.) and then fly to shore.  You'd need helicopters with longer than normal range (some have that kind of range, and others can have an extra fuel tank added). I think the timing would be pretty daunting, so perhaps it'd be better (also from a cost perspective, perhaps) to emulate what the Air Force did way back in 1960 and after; use a cargo plane. 

At the risk of going farther down the rabbit hole....
A big problem with staging helicopters from the ASDS is what happens if they fail to take off?  They would have people and a helicopter on the ASDS. That would probably mean calling off the booster recovery.

Hrmmm. I think you're right - they'd have to skip the F9 recovery. That, plus other factors (such as the tight margins for them getting back to land) probably make this a bad idea.

A fixed wing old cargo plane, on the other hand, would be easier, cheaper, and not potentially hinder F9 recovery. Water recovery would be even better IMHO, if (and that's a mighty big if) the fairings can tolerate salt water landing and immersion.



Title: Re: Fairing reuse
Post by: OnWithTheShow on 06/04/2016 05:39 am

Quote

Hrmmm. I think you're right - they'd have to skip the F9 recovery. That, plus other factors (such as the tight margins for them getting back to land) probably make this a bad idea.


Plenty of ships with helipads out there to rent.
Title: Re: Fairing reuse
Post by: guckyfan on 06/04/2016 05:46 am
They can use a ship with helipad. But what when they have caught the bus? The helicopter would likely not have the range to get to land from there. How to land the fairing under parachute on a ship? Something with a flat area as large as the big barges may be needed. It would not necessarily need station keeping thrusters.
Title: Re: Fairing reuse
Post by: Kaputnik on 06/04/2016 05:52 am
Are we completely sure that helicopter recovery is what they intend to do?

No, everything is speculation at this point.
Title: Re: Fairing reuse
Post by: DAZ on 06/04/2016 02:28 pm
As with most experiments on recovery that SpaceX does, they start with the simplest/cheapest options they can think of and only add more complexity/cost when they find those solutions are not tenable/optimal.  At the moment the simplest/cheapest option would appeared to let the fairing just splash into the ocean and then tow them back to land or possibly to the barge.  Even if SpaceX ultimately thinks this may not be the final working solution this is probably where they will start until they actually get fairings back and see how they fare their ordeal.  This is how they are doing it with the returning stages. After they have these fairings in hand and can inspect them only then will they determine what additional modifications they might make.  So even if SpaceX is thinking that they might need to ultimately use aircraft retrieval for these fairings the 1st recoveries we observe will still probably be those from the ocean.
Title: Re: Fairing reuse
Post by: georgegassaway on 06/04/2016 07:12 pm
DAZ,  what you say makes a lot of sense.

First they need to get one or two fairings back just to see what shape they are in after enduring re-entry and splashdown in the ocean with whatever type of chute is used (probably simple non-steerable).  Also, likely documentation with several GoPros (they did that with one GoPro years ago, for more serious testing they’d use several plus a likely small “black box” to record all sorts of sensor data including G sensors).  I also would suspect the fairings themselves do not tend to float (unless they have a honeycomb construction or some other fabrication method that adds buoyancy as a side benefit), so they may need to add some buoyancy to them such as foam (K.I.S.S.) or inflatable air bags (If they use a ballute to help with re-entry, that could do double duty as a “bouy” after landing)

If  the fairings are badly damaged by re-entry heating or aerodynamic loads, that would be a key upstream problem to work on , such as perhaps a “Ballute” system to cause enough high drag (and stability) during re-entry to make the heating effects gentler (and the fairings may not be practical to make them aerodynamically stable without some deployable system such as ballute or far more complex means).

So once they get 1-2 back and learn what needs to be done, and what is fine as-is, they can move on with upgrades and determine whether a parachute landing into the ocean is good enough, to refine the chute system, or if they have to try to snag it with a copter (To me the only good reason for copter air-snag would be if the fairings can't get soaked in saltwater).

I am 99%+ sure that an “airplane” based horizontal air-snag recovery is totally impractical.  The aerodynamic and mass forces of a small  Discoverer / Corona satellite being snagged horizontally, and the forces of the relatively HUGE fairing halves are orders of magnitude differences.  Indeed the fairings are also relatively flimsy once separated, they would tend to deform and rip due to the massive loads of the air-snag, as well as spin and wobble like crazy until ripping apart.  To “reel one inside” the fuselage, would require a cargo plane of about the size of a C-5 , and one heck of a method to stabilize the fairing half so it could be reeled inside the rear opening.  Actually I am not even sure a fairing would be small enough to fit thru the rear ramp door of a C-5, and it seems so unlikely that a horizontal air-snag by airplane could be practical that I’m not inclined to go look up the stats on fairing dimensions vs C-5 or other very large cargo aircraft.
Title: Re: Fairing reuse
Post by: Kabloona on 06/05/2016 12:03 am
Quote
  I also would suspect the fairings themselves do not tend to float (unless they have a honeycomb construction or some other fabrication method that adds buoyancy as a side benefit),

The fairings do have a honeycomb core and we've already seen at least one fairing half wash up on shore (the one from which the GoPro video of fairing descent was recovered). Additional flotation wouldn't hurt, of course, but the fairings are likely quite buoyant already.
Title: Re: Fairing reuse
Post by: Bob Shaw on 06/05/2016 12:35 am
'Buoyant' is pretty easy. Using the suckers again is hard.
Title: Re: Fairing reuse
Post by: ppb on 06/05/2016 12:52 am
Plus I really doubt a steerable chute could have the accuracy to get it down onto a boat anyway.
Military precision airdrop steerable parafoils ( Atair, MMIST, SPADES, Zodiac etc) had accuracy of about 50-200 meters ~8 years ago. Depending on payload size and drop altitude of course. Not hitting a barge with that, but i guess military never had a land on a dime requirement.
Maybe the boat can drive the last 50-100m to get under the fairing. It doesn't have to land on a droneship, since a fairing coming down under a chute isn't all that dangerous... mass in only ~2t, terminal velocity is probably a few m/s, and there's no explosives aboard. Land it on a airbag sitting on the deck.
I really like this idea if salt water immersion is an obstacle to reuse. After a few notable learning experiences (see e.g. F1 fuel slosh failure) Spacex has proven themselves to harbor a pretty good stable of controls engineers. I wouldn't be surprised if they could reduce parafoil CEP to the point where the ship catcher wouldn't have to move much at all (Yes, I know analysis without numbers is just an opinion, to quote another poster's byline)

Sent from my LGLS885 using Tapatalk

Title: Re: Fairing reuse
Post by: Bob Shaw on 06/05/2016 01:10 am
Plus I really doubt a steerable chute could have the accuracy to get it down onto a boat anyway.
Military precision airdrop steerable parafoils ( Atair, MMIST, SPADES, Zodiac etc) had accuracy of about 50-200 meters ~8 years ago. Depending on payload size and drop altitude of course. Not hitting a barge with that, but i guess military never had a land on a dime requirement.
Maybe the boat can drive the last 50-100m to get under the fairing. It doesn't have to land on a droneship, since a fairing coming down under a chute isn't all that dangerous... mass in only ~2t, terminal velocity is probably a few m/s, and there's no explosives aboard. Land it on a airbag sitting on the deck.
I really like this idea if salt water immersion is an obstacle to reuse. After a few notable learning experiences (see e.g. F1 fuel slosh failure) Spacex has proven themselves to harbor a pretty good stable of controls engineers. I wouldn't be surprised if they could reduce parafoil CEP to the point where the ship catcher wouldn't have to move much at all (Yes, I know analysis without numbers is just an opinion, to quote another poster's byline)

Sent from my LGLS885 using Tapatalk



Look at the AI in quadcopter drones; give the latest commercially available examples a Lat/Long and they'll go there, or follow a signal. SpaceX doesn't need to re-invent the wheel, just to place a landing pad in the right place. Once the things hit the water they are probably useless anyway...
Title: Re: Fairing reuse
Post by: meekGee on 06/05/2016 03:57 am
Or use an airplane to recover them. Doesn't have to be a helicopter. Corona used airplanes. Seems like it'd be cheaper, faster, maybe safer. Airplanes are lower maintenance, can cover a much longer range, and SpaceX already uses them sometimes just for observing the booster recovery attempts.

Once a fairing halve is caught by the plane, however, I'm not entirely sure how it'd be gently placed on the ground.

There's a trick to that.

If the line is long, and the airplane flies in a tight circle, the bottom of the line remains stationary  (so the line describes a down-vertex cone.

Title: Re: Fairing reuse
Post by: pericynthion on 06/05/2016 05:54 am
There's a trick to that.

If the line is long, and the airplane flies in a tight circle, the bottom of the line remains stationary  (so the line describes a down-vertex cone.

Unfortunately that doesn't work well if there's any wind.  But there are some tricks you can do.
Title: Re: Fairing reuse
Post by: The Amazing Catstronaut on 06/05/2016 06:02 am
Could it pop floatation bags and would it stay in one (well, two) piece(s) under wave action? I'm trying to think of ways a fairing half could reach the surface of the sea without being either totally inundated or lost under anything but the most ideal sea conditions, just as a counterpoint to air recovery. I'm not having very good ideas.
Title: Re: Fairing reuse
Post by: AncientU on 06/05/2016 01:44 pm
When fairings are making a controlled descent, are there any more significant (dangerous) pieces planned to fall immediately downrange of the launch site?  (Second stages obviously deorbit in the Southern Sea or elsewhere.)

Will this either begin to shrink the NOTAM restrictions, or eventually eliminate them?
Can reusable rockets eventually be launched from interior (desert SouthWest, for instance) launch sites?

This could be a driver for fairing recovery, since the cost argument seems to be weak, and production capacity is trivial to scale.  If it is just cost, then someone is planning for really cheap launches.
Title: Re: Fairing reuse
Post by: Lar on 06/05/2016 01:57 pm
This could be a driver for fairing recovery, since the cost argument seems to be weak, and production capacity is trivial to scale.  If it is just cost, then someone is planning for really cheap launches.
Weak cost argument? If fairings really cost 5M a pair and you can recover/refurbish for 30% of that steady state (long term that's a generous number I GUESS (don't know)) it's a strong argument. even if it's only 3M or so you save a time.

As for scaling capacity, there's a step function there somewhere if you're already running parts of the process 24/7, they may want to avoid the cost of duplicating most or all of the line. 

Do we have hard numbers on the production process and timings?
Title: Re: Fairing reuse
Post by: cscott on 06/05/2016 02:59 pm
AIUI the production capacity is *not* trivial to scale.  The equipment is large, a lot of manual labor is involved; you'd need to build a new factory to hold the new equipment and train a new workforce.  And those are then ongoing fixed costs you incur even when you don't happen to need the excess capacity.

SpaceX has run the spreadsheets.
Title: Re: Fairing reuse
Post by: joek on 06/05/2016 03:08 pm
...
This could be a driver for fairing recovery, since the cost argument seems to be weak, and production capacity is trivial to scale.  If it is just cost, then someone is planning for really cheap launches.

If they save $1 in all-up costs, they are ahead.  That they are seriously pursuing fairing recovery-reuse at this time suggests that it is high on the list of potential cost saving measures.
Title: Re: Fairing reuse
Post by: AncientU on 06/05/2016 04:23 pm
...
This could be a driver for fairing recovery, since the cost argument seems to be weak, and production capacity is trivial to scale.  If it is just cost, then someone is planning for really cheap launches.

If they save $1 in all-up costs, they are ahead.  That they are seriously pursuing fairing recovery-reuse at this time suggests that it is high on the list of potential cost saving measures.

I agree that the cost argument is most likely -- though I doubt they'd do all of this capability augmentation for your $1 net per launch (did you mean $1M?).  If fairing pairs are $5M as Lar speculates (my guess would be half or less of that), they would have to save a substantial portion of that to avoid locking in that $5M into the base price.  If they can save a substantial portion, say 75% or more, then baseline cost improvement is relevant.

Going back to the circa $43M price for reused booster, a couple million dollars saved on fairing recovery is less than 5%... never getting to the ultimate price range that way.  But, that said, if they see $2-3M as significant cost factor down the road, then this could actually be a harbinger of something incredible.
Title: Re: Fairing reuse
Post by: guckyfan on 06/05/2016 05:13 pm
Production capacity may not be trivial to scale. It seems they are limited in space at the Hawthorne site. They may have to transfer the whole fairing production to another location to increase capacity. They may not want to do that.

Plus Elon Musks just likes reuse as long as the cost balance is positive.
Title: Re: Fairing reuse
Post by: Lar on 06/05/2016 05:17 pm
I think they'd do it for positive 1.00 USD per fairing. Because it's a way to learn about stuff, and just because it was barely marginal on this ship, it might be hugely positive on the next one.

I don't think it's barely marginal, I think it's a big win but even if it was.... The 5M isn't from me, I read it somewhere but I forget where. I think Musk said it was in the millions...
Title: Re: Fairing reuse
Post by: MP99 on 06/05/2016 07:14 pm
For FH, which obviously stages the centre core later, could the fairing be retained on the core, and recovered as part of the core landing?

It would obviously imply a larger fairing which would also encapsulate the upper stage. Could imagine this causing various issues, including loss of commonality with F9 fairing.

Cheers, Martin
Title: Re: Fairing reuse
Post by: oiorionsbelt on 06/06/2016 12:00 am
It appears as though the fairings end up as flotsam.
Get it in the water gently, pick it up quickly, design for salt water and see if it's any good to use again.
Title: Re: Fairing reuse
Post by: joek on 06/06/2016 03:30 am
I agree that the cost argument is most likely -- though I doubt they'd do all of this capability augmentation for your $1 net per launch (did you mean $1M?).
...

Meant $1.00.  That SpaceX is pursuing fairing reuse at this point suggests that it is potentially low-hanging fruit.  That is, if you put recovery-reuse-cost-benefit on a Pareto chart, it would probably be near the top.  In any case, that savings from any single effort must be large in order to justify pursuit is a disease that SpaceX does not seem to be afflicted with.
Title: Re: Fairing reuse
Post by: wannamoonbase on 06/06/2016 04:58 am
I agree that the cost argument is most likely -- though I doubt they'd do all of this capability augmentation for your $1 net per launch (did you mean $1M?).
...

Meant $1.00.  That SpaceX is pursuing fairing reuse at this point suggests that it is potentially low-hanging fruit.  That is, if you put recovery-reuse-cost-benefit on a Pareto chart, it would probably be near the top.  In any case, that savings from any single effort must be large in order to justify pursuit is a disease that SpaceX does not seem to be afflicted with.

I think it could also mean that upper stage recovery is some distance down the road.   Falcon 9 replacement type stuff.
Title: Re: Fairing reuse
Post by: S.Paulissen on 06/06/2016 05:25 am
It could also mean they need fairings as much as they need reused cores to launch satellites.
Title: Re: Fairing reuse
Post by: Mariusuiram on 06/06/2016 06:33 am
Why not just use JPADS and land the fairings on their own ASDS. The 10,000 lb version is already called DragonFly. Could be confusing, but their heart's in the right place.   ::)

https://en.wikipedia.org/wiki/Joint_Precision_Airdrop_System
http://www.militaryaerospace.com/articles/2014/04/computer-parachute-airdrop.html

From reading their brochures, the 10k version is only accurate to 250 m while the smaller (2k?) version is only accurate to 150 m. Thats reasonably tight, but nowhere near tight enough to land on any vessel at sea.

From what I can tell, the smaller version should be enough as each fairing half will have its own system.
Title: Re: Fairing reuse
Post by: JamesH65 on 06/06/2016 09:41 am
I wonder is small winglets on the fairings (perhaps retractable during launch) would enable them to 'fly', converting some vertical to horizontal velocity, should, give more accuracy to the landing point, and perhaps even ability to 'crash' land in to netting or similar on an ASDS. Would weigh less than a parachute I suspect.

Effectively, make the fairing a steerable lifting body.
Title: Re: Fairing reuse
Post by: Kaputnik on 06/06/2016 01:00 pm
Another slightly out-there idea: the fairing's biggest weakness will be the lack of stiffness once separted into halves.
It would be an interesting little engineering project to design a strut would somehow not get in the way of the payload, but following fairing jettison would deploy to span the width of the fairing half and brace it again.
Title: Re: Fairing reuse
Post by: rpapo on 06/06/2016 01:06 pm
Another slightly out-there idea: the fairing's biggest weakness will be the lack of stiffness once separted into halves.
It would be an interesting little engineering project to design a strut would somehow not get in the way of the payload, but following fairing jettison would deploy to span the width of the fairing half and brace it again.
Even so, we have now multiple examples of the fairing surviving reentry and impact into the ocean.  It seems to be stiff enough as it is.  IMHO, what is needs is some sort of passive or active attitude control, with and without air flowing past.  If it can be kept on an even keel (rounded surface down, nose forward), it should have a relatively low terminal velocity.

A weight around one-third back from the nose should give it passive aerodynamic stability.
Title: Re: Fairing reuse
Post by: cscott on 06/06/2016 01:53 pm


Even so, we have now multiple examples of the fairing surviving reentry and impact into the ocean. 

We have multiple examples of *pieces* of the fairing being discovered after falling in the ocean.  Getting down intact has certainly not been shown.
Title: Re: Fairing reuse
Post by: kevin-rf on 06/06/2016 02:44 pm
Do we know what the bottle necks in fairing production are? If it is the autoclave, then expanding production could be very expensive.
Title: Re: Fairing reuse
Post by: envy887 on 06/06/2016 03:27 pm
Why not just use JPADS and land the fairings on their own ASDS. The 10,000 lb version is already called DragonFly. Could be confusing, but their heart's in the right place.   ::)

https://en.wikipedia.org/wiki/Joint_Precision_Airdrop_System
http://www.militaryaerospace.com/articles/2014/04/computer-parachute-airdrop.html

From reading their brochures, the 10k version is only accurate to 250 m while the smaller (2k?) version is only accurate to 150 m. Thats reasonably tight, but nowhere near tight enough to land on any vessel at sea.

From what I can tell, the smaller version should be enough as each fairing half will have its own system.

That's 150 to 250 FEET, which is 50-75 meters, which is close to the deck size of a ASDS. More barges?
Title: Re: Fairing reuse
Post by: Lar on 06/06/2016 03:29 pm
I thought we separated the "here's how SpaceX COULD do reuse" from "here's concrete information about what they actually are doing" so we had two threads. But maybe I'm imagining that...
Title: Re: Fairing reuse
Post by: Bubbinski on 06/19/2016 02:31 am
Did SpaceX attempt a fairing recovery on the Eutelsat/ABS mission?
Title: Re: Fairing reuse
Post by: cscott on 06/19/2016 02:41 am
No evidence that I could see: no visible RCS from the fairing after separation, no abnormal dallying of Go Searcher at sea.  Both the Go * ships appear to have headed straight back to port.

This isn't to claim there is any evidence that fairing recovery *wasn't* attempted: the fairing halves were only very briefly visible from the S1/S2 rocket cams, and a failed recovery attempt would probably also have resulted in Go Searcher having nothing to do.  I'm just saying there is no public evidence either way, at least that I know of, and I was looking for it.
Title: Re: Fairing reuse
Post by: Adriano on 06/25/2016 06:19 am
I think the fairing can be reassembled as follows. The fairing is divided in three equal sections (process symmetrical and more stable than with two sections). The tree parts are connected with hinges and weak springs. the central section has spacers keeping the necessary distance from the load during the process. The process begins with the un latching of the two side sections and starting moving them apart with a spring released by the latch or similar. When the two side sections have completed a 90 degree rotation, the springs in the hinges begin to slow their motion. The inertia of the moving side sections is transmitted to the center section that will be dragged away from the load. When the three sections are clear from the load, the hinge springs will revert the motion of the side sections that will start closing. When the two side sections fully close, a latch will anchor them and the fairing is fully reassembled!
Title: Re: Fairing reuse
Post by: Jim on 06/25/2016 10:26 am
I think the fairing can be reassembled as follows. The fairing is divided in three equal sections (process symmetrical and more stable than with two sections). The tree parts are connected with hinges and weak springs. the central section has spacers keeping the necessary distance from the load during the process. The process begins with the un latching of the two side sections and starting moving them apart with a spring released by the latch or similar. When the two side sections have completed a 90 degree rotation, the springs in the hinges begin to slow their motion. The inertia of the moving side sections is transmitted to the center section that will be dragged away from the load. When the three sections are clear from the load, the hinge springs will revert the motion of the side sections that will start closing. When the two side sections fully close, a latch will anchor them and the fairing is fully reassembled!

Asymmetrical separation isn't going to work.  There are aeroloads and thrust.   It can't remain attached at the base while parts start rotating
Title: Re: Fairing reuse
Post by: RAN on 08/11/2016 10:37 pm
I was recently at a tour of SpaceX Hawthorne and my guide offered information on fairing recovery.

He cautioned that it was still early, but one method of interest for recovery would be to use a large semi-inflated bag to cushion the landing.  He described it like a larger version of "bounce bags" that you might find at a summer camp.
Title: Re: Fairing reuse
Post by: Robotbeat on 08/12/2016 07:57 pm
I was recently at a tour of SpaceX Hawthorne and my guide offered information on fairing recovery.

He cautioned that it was still early, but one method of interest for recovery would be to use a large semi-inflated bag to cushion the landing.  He described it like a larger version of "bounce bags" that you might find at a summer camp.
They cost about $1000 online for a 3m by 7m one, so you could buy a thousand of them for a million dollars and place them in a 100m by 200m grid. Should be able to hit that with a guided parasail.
Title: Re: Fairing reuse
Post by: meekGee on 08/12/2016 09:19 pm
I was recently at a tour of SpaceX Hawthorne and my guide offered information on fairing recovery.

He cautioned that it was still early, but one method of interest for recovery would be to use a large semi-inflated bag to cushion the landing.  He described it like a larger version of "bounce bags" that you might find at a summer camp.
They cost about $1000 online for a 3m by 7m one, so you could buy a thousand of them for a million dollars and place them in a 100m by 200m grid. Should be able to hit that with a guided parasail.

Air bags not carried by the fairings?  There's a concept...

Like that skydiver that jumped into a net instead of using a parachute...   That'd be funny.

So who knows, giant autonomous station-keeping air bags... ASDB! 

Title: Re: Fairing reuse
Post by: oiorionsbelt on 08/12/2016 09:59 pm
I was recently at a tour of SpaceX Hawthorne and my guide offered information on fairing recovery.

He cautioned that it was still early, but one method of interest for recovery would be to use a large semi-inflated bag to cushion the landing.  He described it like a larger version of "bounce bags" that you might find at a summer camp.
They cost about $1000 online for a 3m by 7m one, so you could buy a thousand of them for a million dollars and place them in a 100m by 200m grid. Should be able to hit that with a guided parasail.
This is not elegant.
Title: Re: Fairing reuse
Post by: envy887 on 08/12/2016 10:01 pm
I mentioned landing on pre-positioned airbags upthread.  A big challenge would be getting a 50m radius deck full of bags out in the middle of the Atlantic.
Title: Re: Fairing reuse
Post by: DAZ on 08/12/2016 10:10 pm
They’ve got 2 tug ships going out there all the time that aren’t towing anything.  Strap the bags together, put some water in the bottom of them so they won’t blow around too easy with something that makes drag at the backend so they can pull straight.  Add a little generator for compressor/lights and there you go.
Title: Re: Fairing reuse
Post by: meekGee on 08/12/2016 10:11 pm
I mentioned landing on pre-positioned airbags upthread.  A big challenge would be getting a 50m radius deck full of bags out in the middle of the Atlantic.

If they do, then you credit for predicting an incredibly unlikely solution that unless I'd heard it from SpaceX, I'd discount really quickly as "it will never happen".

You know, like barges.

My money is still on something that goes up and down with the fairing, weight penalty and all.
Title: Re: Fairing reuse
Post by: envy887 on 08/12/2016 10:31 pm
They’ve got 2 tug ships going out there all the time that aren’t towing anything.  Strap the bags together, put some water in the bottom of them so they won’t blow around too easy with something that makes drag at the backend so they can pull straight.  Add a little generator for compressor/lights and there you go.

A giant inflatable raft, huh? That's brilliant. 8)
Title: Re: Fairing reuse
Post by: Robotbeat on 08/12/2016 11:21 pm
I was recently at a tour of SpaceX Hawthorne and my guide offered information on fairing recovery.

He cautioned that it was still early, but one method of interest for recovery would be to use a large semi-inflated bag to cushion the landing.  He described it like a larger version of "bounce bags" that you might find at a summer camp.
They cost about $1000 online for a 3m by 7m one, so you could buy a thousand of them for a million dollars and place them in a 100m by 200m grid. Should be able to hit that with a guided parasail.
This is not elegant.
I take that as a compliment. :)

http://spacecraft.ssl.umd.edu/akins_laws.html
Akin's Laws of Spacecraft Design:
"36. Any run-of-the-mill engineer can design something which is elegant. A good engineer designs systems to be efficient. A great engineer designs them to be effective."
Title: Re: Fairing reuse
Post by: Nomadd on 08/13/2016 01:57 am
 You need to stop posting these ideas in a public forum before Boeing or BO patents them all.
 (I'm for the giant ball pit landing zone myself)
Title: Re: Fairing reuse
Post by: CuddlyRocket on 08/13/2016 06:13 pm
I was recently at a tour of SpaceX Hawthorne and my guide offered information on fairing recovery.

He cautioned that it was still early, but one method of interest for recovery would be to use a large semi-inflated bag to cushion the landing.  He described it like a larger version of "bounce bags" that you might find at a summer camp.
They cost about $1000 online for a 3m by 7m one, so you could buy a thousand of them for a million dollars and place them in a 100m by 200m grid. Should be able to hit that with a guided parasail.

Air bags not carried by the fairings?  There's a concept...

Like that skydiver that jumped into a net instead of using a parachute...   That'd be funny.

So who knows, giant autonomous station-keeping air bags... ASDB! 

Why not a net? What's the terminal velocity of a fairing compared to a human?
Title: Re: Fairing reuse
Post by: envy887 on 08/13/2016 07:32 pm
Why not a net? What's the terminal velocity of a fairing compared to a human?

Musk said they were planning to try steerable chutes, so terminal velocity is probably only a few m/s. The only question is whether they are willing to splash them, use a built-in inflatables, or land them on something.

Stretching a net between two ships seems a lot harder than floating a bunch of airbags though...
Title: Re: Fairing reuse
Post by: docmordrid on 08/13/2016 09:04 pm
I'm thinking the collapsed air bag(s) will be conformal to the inside of the fairing, expanded by an N2 cylinder or chemical gas generator. Access cutouts or uncovered  positions as needed per fairing design.

Basically, large Turtle-Pacs

Perhaps the parafoil will be externally mounted and conformal under a blister fairing?
Title: Re: Fairing reuse
Post by: meekGee on 08/14/2016 06:44 am
I'm thinking the collapsed air bag(s) will be conformal to the inside of the fairing, expanded by an N2 cylinder or chemical gas generator. Access cutouts or uncovered  positions as needed per fairing design.

Basically, large Turtle-Pacs

Perhaps the parafoil will be externally mounted and conformal under a blister fairing?

Yeah, but bouncing around in the waves, this is a large structure, and it's in two pieces that are much weaker than the whole thing.

I'm honestly baffled by all of this.  Heli recovery sounds odd because the range is so long.   Airplane recovery I can believe, but landing it is tricky. 

Hey, if the fairing is going to see salt water anyway, maybe have it sink, and hang underwater using a buoy. 

Then pick it up with a boat and a crane.
Title: Re: Fairing reuse
Post by: gregpet on 08/15/2016 03:24 am
It would make sense that SpaceX would want the fairings to end up as close to a recovery vessel as possible.  Given the success using GPS and steering/landing 1st stage, why wouldn't SpaceX not bring fairings back to OCISLO (using steerable chutes and GPS to steer).  Maybe even try to land them on the barge somehow (after the first stage lands so timing would obviously have to work).

Given the height of release, do you have enough altitude to cove the ground (water) back to the SpaceX flotilla?   
Title: Re: Fairing reuse
Post by: Comga on 08/15/2016 03:56 am
From over in the Missions section

(snip)


 I happened to watch the launch this morning standing next to some of the crew who work the Go Quest and Go Searcher and among other things they mentioned that they secure the rockets where they land as soon as possible and don't try to move them on deck for fear of toppling. They said the last successful one was a real handful with the bent leg.

They also said they are routinely within 5 miles of the splashdown point of the fairings and they can see them "tumbling like a leaf" before hitting the water, where they then break up. Pieces are recovered.


If they are whole and tumbling within sight one would think some moderate amount of parachute deployed at low altitude might be enough to get them into the water without breaking up.
Title: Re: Fairing reuse
Post by: meekGee on 08/15/2016 05:30 am
It would make sense that SpaceX would want the fairings to end up as close to a recovery vessel as possible.  Given the success using GPS and steering/landing 1st stage, why wouldn't SpaceX not bring fairings back to OCISLO (using steerable chutes and GPS to steer).  Maybe even try to land them on the barge somehow (after the first stage lands so timing would obviously have to work).

Given the height of release, do you have enough altitude to cove the ground (water) back to the SpaceX flotilla?   

I'm surprised at that.  The second stage is burning for a while there before the fairings are jettisoned.  Covering more distance, and increasing velocity...

And without a lot of aerodynamics, and only, what, 10 miles of somewhat useful atmosphere - I can't see them flying back.  I'd think they need to back track 100s of miles.
Title: Re: Fairing reuse
Post by: Robotbeat on 08/15/2016 05:43 am
There's a little more than 10 miles, but yeah. I think you could glide for about 100 miles maybe. More like 50 miles reliably.
Title: Re: Fairing reuse
Post by: envy887 on 08/15/2016 02:00 pm
For JCSAT-16, S1 sep happened at 2265 m/s velocity and ~1000 m/s change in altitude, so ~2050 m/s downrange velocity. Fairing sep happened 59 seconds later at 2500 m/s velocity and ~400 m/s change in altitude, so ~2460 m/s downrange velocity.

It shouldn't be too hard to figure the downrange distance between the fairings and the S1 as they each coast uphill after sep, but things get a lot tougher after that. To start with, the downrange distance between them at fairing sep is the average velocity of the fairing relative to the S1, multiplied by the time that it is accelerating: d_sep = (v_S1 - v_f)/2 * 59 = 12,100 m.

The S1 is coasting up for ~100 seconds to bleed off the 1,000 m/s vertical velocity at MECO. MECO is at ~65 km, so it coasts up to ~116 km at about T+253 sec. Fairing sep is at 113 km altitude with enough velocity up to coast to ~120 km about 40 seconds after sep (T+252 sec). Additional distance between the two while going uphill is 410 m/s for 40 seconds, or 16.5 km.

So the S1 and fairing end up at nearly the same apogee at almost exactly the same time, separated by about 28.5 km, but with the fairing still going downrange somewhat faster. Depending on how much faster aero drag slows the relatively light and large fairing, the S1 might actually land farther downrange than the fairings.
Title: Re: Fairing reuse
Post by: Comga on 08/15/2016 03:59 pm
For JCSAT-16, S1 sep happened at 2265 m/s velocity and ~1000 m/s change in altitude, so ~2050 m/s downrange velocity. Fairing sep happened 59 seconds later at 2500 m/s velocity and ~400 m/s change in altitude, so ~2460 m/s downrange velocity.

It shouldn't be too hard to figure the downrange distance between the fairings and the S1 as they each coast uphill after sep, but things get a lot tougher after that. To start with, the downrange distance between them at fairing sep is the average velocity of the fairing relative to the S1, multiplied by the time that it is accelerating: d_sep = (v_S1 - v_f)/2 * 59 = 12,100 m.

The S1 is coasting up for ~100 seconds to bleed off the 1,000 m/s vertical velocity at MECO. MECO is at ~65 km, so it coasts up to ~116 km at about T+253 sec. Fairing sep is at 113 km altitude with enough velocity up to coast to ~120 km about 40 seconds after sep (T+252 sec). Additional distance between the two while going uphill is 410 m/s for 40 seconds, or 16.5 km.

So the S1 and fairing end up at nearly the same apogee at almost exactly the same time, separated by about 28.5 km, but with the fairing still going downrange somewhat faster. Depending on how much faster aero drag slows the relatively light and large fairing, the S1 might actually land farther downrange than the fairings.

All well and good, but it doesn't matter.
Quote
[The recovery crew] said they are routinely within 5 miles of the splashdown point of the fairings and they can see them "tumbling like a leaf" before hitting the water, where they then break up.

I am as surprised as anyone that the fairings don't come down a hundred kilometers downrange, but they don't.
There is no need for said "50 miles" of fairing glide range, or even any controlled landing (yet). 
It seems to be not a large step to get the fairings into the water without being destroyed, so that they can be fetched whole by the recovery crew just like the "Pieces are recovered".
Title: Re: Fairing reuse
Post by: Kaputnik on 08/15/2016 04:22 pm
Is that quote from the ASDS/Elsbeth etc crew, or from the Go Searcher crew who are/were specifically looking for the fairings?
Title: Re: Fairing reuse
Post by: Hobbes-22 on 08/15/2016 05:13 pm

All well and good, but it doesn't matter.
Quote
[The recovery crew] said they are routinely within 5 miles of the splashdown point of the fairings and they can see them "tumbling like a leaf" before hitting the water, where they then break up.

I am as surprised as anyone that the fairings don't come down a hundred kilometers downrange, but they don't.
There is no need for said "50 miles" of fairing glide range, or even any controlled landing (yet). 
It seems to be not a large step to get the fairings into the water without being destroyed, so that they can be fetched whole by the recovery crew just like the "Pieces are recovered".

The first stage (when in the proper orientation for recovery) has a much higher ratio of mass vs. surface area than the fairings so it experiences much less deceleration due to drag.
Title: Re: Fairing reuse
Post by: Jcc on 08/15/2016 06:03 pm

All well and good, but it doesn't matter.
Quote
[The recovery crew] said they are routinely within 5 miles of the splashdown point of the fairings and they can see them "tumbling like a leaf" before hitting the water, where they then break up.

I am as surprised as anyone that the fairings don't come down a hundred kilometers downrange, but they don't.
There is no need for said "50 miles" of fairing glide range, or even any controlled landing (yet). 
It seems to be not a large step to get the fairings into the water without being destroyed, so that they can be fetched whole by the recovery crew just like the "Pieces are recovered".

The first stage (when in the proper orientation for recovery) has a much higher ratio of mass vs. surface area than the fairings so it experiences much less deceleration due to drag.

It's a pity SpaceX cut off the "falling back" video before it hit the atmosphere, but you can bet they know what happens to it:
https://m.youtube.com/watch?v=4_sLTe6-7SE

Apparently, it remains intact until it hits the water at terminal velocity, so a parachute would allow it to splash down intact, but I would think it much better if it never falls n saltwater.

So, my thought is to put 2 helicopters on a barge or ship with helipads, and take off at launch time, snag the fairings in mid-air, and set them back on the barge and land again on the helipads. Solves the helicopter endurance problem.
Title: Re: Fairing reuse
Post by: rickyramjet on 08/15/2016 08:38 pm

Apparently, it remains intact until it hits the water at terminal velocity, so a parachute would allow it to splash down intact, but I would think it much better if it never falls n saltwater.

So, my thought is to put 2 helicopters on a barge or ship with helipads, and take off at launch time, snag the fairings in mid-air, and set them back on the barge and land again on the helipads. Solves the helicopter endurance problem.
I think the cost of two ships, two helicopters, crew, fuel, and always on call for whenever a launch is planned would soon negate the advantage of fairing recovery.  I would also imagine trying to snag a fairing on a chute at night would be super difficult and dangerous.  Now that S1 recovery kinks are getting ironed out I think we'll soon see fairings with chutes of some kind, and a soft landing in the ocean.  Being composite it may be that salt water is not as terrible as many think. 
Title: Re: Fairing reuse
Post by: abaddon on 08/15/2016 09:09 pm
Is that quote from the ASDS/Elsbeth etc crew, or from the Go Searcher crew who are/were specifically looking for the fairings?
From the original quote up above:
Quote
next to some of the crew who work the Go Quest and Go Searcher
Title: Re: Fairing reuse
Post by: abaddon on 08/15/2016 09:10 pm
I think the cost of two ships, two helicopters, crew, fuel, and always on call for whenever a launch is planned would soon negate the advantage of fairing recovery.
The fairing costs in the "millions", I've seen the estimate of 3-5 million thrown around.  You can do a lot for that, assuming the results are worth it.

Not saying it would be easy or cheap.
Title: Re: Fairing reuse
Post by: Jcc on 08/15/2016 09:44 pm

Apparently, it remains intact until it hits the water at terminal velocity, so a parachute would allow it to splash down intact, but I would think it much better if it never falls n saltwater.

So, my thought is to put 2 helicopters on a barge or ship with helipads, and take off at launch time, snag the fairings in mid-air, and set them back on the barge and land again on the helipads. Solves the helicopter endurance problem.
I think the cost of two ships, two helicopters, crew, fuel, and always on call for whenever a launch is planned would soon negate the advantage of fairing recovery.  I would also imagine trying to snag a fairing on a chute at night would be super difficult and dangerous.  Now that S1 recovery kinks are getting ironed out I think we'll soon see fairings with chutes of some kind, and a soft landing in the ocean.  Being composite it may be that salt water is not as terrible as many think.

You may be right, we will find out. They can have gps and a radio transmitter to report their location in real time, and lights to help see them at night. That would be useful for a splashdown recovery also.
Title: Re: Fairing reuse
Post by: Comga on 08/17/2016 04:18 am
All well and good, but it doesn't matter.
Quote
[The recovery crew] said they are routinely within 5 miles of the splashdown point of the fairings and they can see them "tumbling like a leaf" before hitting the water, where they then break up.

I am as surprised as anyone that the fairings don't come down a hundred kilometers downrange, but they don't.
There is no need for said "50 miles" of fairing glide range, or even any controlled landing (yet). 
It seems to be not a large step to get the fairings into the water without being destroyed, so that they can be fetched whole by the recovery crew just like the "Pieces are recovered".

(snip)
Apparently, it remains intact until it hits the water at terminal velocity, so a parachute would allow it to splash down intact, but I would think it much better if it never falls n saltwater.

So, my thought is to put 2 helicopters on a barge or ship with helipads, and take off at launch time, snag the fairings in mid-air, and set them back on the barge and land again on the helipads. Solves the helicopter endurance problem.

Define "better" and remember that "Better is the enemy of good enough".

We generally agreed to NOT propose mechanical solutions and wait for SpaceX to tell us what they are actually doing.

I didn't say how SpaceX could do that.  Risking violating this agreement, parachutes are a solution SpaceX has tried to use, back on Falcon 1 and the original Falcon 9.  Those boosters didn't survive reentering the atmosphere, so they never got to the point they could deploy their parachutes.  However we have reliable information from participants that this is not the case for fairings.

It still seems that the fairing halves' flight could be changed from "falling leaf" to something stable. With the right angle and reduced velocity, they could land without breaking up.  Then SpaceX can see if salt water immersion is fatal or tolerable, if it is "good enough" or if they need something "better".
Title: Re: Fairing reuse
Post by: guckyfan on 08/17/2016 07:22 am
Then SpaceX can see if salt water immersion is fatal or tolerable, if it is "good enough" or if they need something "better".

That is the one thing I expect them to know already. It is quite easy to dump a piece into the water and get it out after a few hours. They may have a defective fairing half to do that or they produce a sheet using the same production methods.

Title: Re: Fairing reuse
Post by: vaporcobra on 08/18/2016 01:22 am
I think the cost of two ships, two helicopters, crew, fuel, and always on call for whenever a launch is planned would soon negate the advantage of fairing recovery.
The fairing costs in the "millions", I've seen the estimate of 3-5 million thrown around.  You can do a lot for that, assuming the results are worth it.

Not saying it would be easy or cheap.

Good to remember that possibly the main motivator behind fairing recovery is the fact that fairings themselves act as a significant roadblock to even relatively minor increases in cadence, and definitely act as a hard ceiling for any serious increases in cadence. Price is very much secondary, though it is significant :)
Title: Re: Fairing reuse
Post by: vaporcobra on 08/18/2016 01:29 am
Quote
I am as surprised as anyone that the fairings don't come down a hundred kilometers downrange, but they don't.
There is no need for said "50 miles" of fairing glide range, or even any controlled landing (yet). 
It seems to be not a large step to get the fairings into the water without being destroyed, so that they can be fetched whole by the recovery crew just like the "Pieces are recovered".

Worth noting that fairings already almost certainly have a significant level of control over their course, at least to the extent that they almost certainly already have RCS and some serious onboard avionics. They likely have a surprising amount of control over where they end up!
Title: Re: Fairing reuse
Post by: joncz on 08/18/2016 11:17 am
Worth noting that fairings already almost certainly have a significant level of control over their course, at least to the extent that they almost certainly already have RCS and some serious onboard avionics. They likely have a surprising amount of control over where they end up!

Source for this claim?
Title: Re: Fairing reuse
Post by: The_Ronin on 08/18/2016 06:06 pm
There was footage a couple launches ago of one of the fairing halves firing RCS thrusters.
Title: Re: Fairing reuse
Post by: Comga on 08/18/2016 10:31 pm
There was footage a couple launches ago of one of the fairing halves firing RCS thrusters.

While a true statement, that does not say they "have a significant level of control over their course".
At least one fairing had RCS.  Whether that was sufficient to control its attitude and course is not known.

If it was sufficient, they would be stable in the atmosphere.  It's unlikely that SpaceX would have abandoned an effective control system, so the fact that the fairings are seen as falling like leaves means it was probably not sufficient.
Title: Re: Fairing reuse
Post by: Burninate on 08/18/2016 11:50 pm
There was footage a couple launches ago of one of the fairing halves firing RCS thrusters.

IIRC, there was footage of a gas release.  This is distinct from an RCS in goals and degree of control.  Emptying the pneumatic cylinders would just be a safety measure designed to ensure that anything which lands on the ground doesn't explode on impact with greater than kinetic energy.
Title: Re: Fairing reuse
Post by: Chris_Pi on 08/19/2016 12:25 am
There was footage a couple launches ago of one of the fairing halves firing RCS thrusters.

While a true statement, that does not say they "have a significant level of control over their course".
At least one fairing had RCS.  Whether that was sufficient to control its attitude and course is not known.

If it was sufficient, they would be stable in the atmosphere.  It's unlikely that SpaceX would have abandoned an effective control system, so the fact that the fairings are seen as falling like leaves means it was probably not sufficient.

RCS to start, But IMHO it's unlikely to be RCS all the way down* - Earlier in this thread:
https://twitter.com/elonmusk/status/738471747540783104 (https://twitter.com/elonmusk/status/738471747540783104)

in response to a question: Are RCS thrusters the sole component for fairing recovery? Are chutes required?

Quote
@mattyteare @karaswisher @waltmossberg @YouTube autosteering chutes will be added soon

So, we'll perhaps see some fairing halves coming back under chutes!

RCS just has to keep it stable until the air is thick enough to deploy a parachute without tangling it. And probably can't do much more - Increasing forces on the fairing will chew through the gas supply pretty quick. Big enough and it could be made to work, But at some point the parachute is probably lighter than the gas bottles.

Since it sounds like they're coming down pretty close to the support ships the impact point must be pretty predictable even if they can't steer them to where they want. Pretty sure they know the ships won't take a hit from a fairing, So the return location is probably known within a couple miles or less. In one piece until impact at least suggests they don't tumble during re-entry.

I think this problem is being solved form separation on down - Control orientation, keep stable until parachutes can be used (Where things appear to be now), Then add expensive/heavy parachutes and prove they work. Soft-splashdown or midair snag last.

*It's turtles, Of course.**
** I couldn't just leave that one sitting there. Had to.

Title: Re: Fairing reuse
Post by: CraigLieb on 08/19/2016 03:38 pm
Green Goblin Glider?
 Deploy small jet engines from the back curve and steer it down using the curved shape to surf the air.
Title: Re: Fairing reuse
Post by: Comga on 08/20/2016 03:00 am
What Chris-PI said

And it IS turtles all the way down!
Title: Re: Fairing reuse
Post by: Jet Black on 08/22/2016 08:09 am
I think the cost of two ships, two helicopters, crew, fuel, and always on call for whenever a launch is planned would soon negate the advantage of fairing recovery.
The fairing costs in the "millions", I've seen the estimate of 3-5 million thrown around.  You can do a lot for that, assuming the results are worth it.

Not saying it would be easy or cheap.

Good to remember that possibly the main motivator behind fairing recovery is the fact that fairings themselves act as a significant roadblock to even relatively minor increases in cadence, and definitely act as a hard ceiling for any serious increases in cadence. Price is very much secondary, though it is significant :)

Given the investment interest that people have in SpaceX, but the relatively closed shop since they aren't going for IPO, I wonder whether it would be worth them starting up a public supplier company to raise the money just for that job.
Title: Re: Fairing reuse
Post by: Geron on 02/20/2017 06:23 am
Gwynne shot well stated the fairings will be recovered this year mid air as submersion in salt water is not allowable.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 02/20/2017 08:44 am
Gwynne's other key quote from the 39A press conference on Friday was that they'd love to re-use fairings and maybe this year you'll see that.

Must imply some fairing recovery attempts rather sooner?
Title: Re: Fairing reuse
Post by: Jarnis on 02/20/2017 10:45 am
Gwynne's other key quote from the 39A press conference on Friday was that they'd love to re-use fairings and maybe this year you'll see that.

Must imply some fairing recovery attempts rather sooner?

Maybe as soon as... 2 weeks  :)
Title: Re: Fairing reuse
Post by: envy887 on 02/20/2017 01:33 pm
Gwynne shot well stated the fairings will be recovered this year mid air as submersion in salt water is not allowable.

Did she specifically say airborne recovery? There are other methods of recovery that can prevent immersion.
Title: Re: Fairing reuse
Post by: Robotbeat on 02/20/2017 02:23 pm
Always important to get exact phrasing.
Title: Re: Fairing reuse
Post by: rsdavis9 on 02/20/2017 02:36 pm
All she said was "we don't want to get it wet".
Never anything about airborne or whatever(barge?).
Title: Re: Fairing reuse
Post by: dorkmo on 02/20/2017 05:10 pm
I think there was some speculation that they were outfitting one of the GO vessels for fairing recovery? Wonder if thats still on the table. Hard to imagine they could use a ship for recovery while keeping the fairings dry. Maybe they could deploy some big inflatable rafts?
Title: Re: Fairing reuse
Post by: cscott on 02/20/2017 11:36 pm
Or RTLS if they have enough cross-range.  I was listening carefully as well and @rsdavis9 has it right. "Not wet" but not specific on how that was to be done.
Title: Re: Fairing reuse
Post by: Kaputnik on 02/21/2017 01:27 pm
Any merit in a poll? Mid air recovery, support ship deck, RTLS, other?
Title: Re: Fairing reuse
Post by: rsdavis9 on 02/21/2017 01:32 pm
If I remember correctly there was already a calculation of maximum glide ratio with a parasail and the distance from launch site to location of meco occurs at and it wouldn't make it back. How about grand bahama(freeport) or abaco?

EDIT
Title: Re: Fairing reuse
Post by: wannamoonbase on 02/21/2017 02:09 pm
Any merit in a poll? Mid air recovery, support ship deck, RTLS, other?

My vote is Mid air recovery depositing the halves on a ship/barge. 
Title: Re: Fairing reuse
Post by: Lee Jay on 02/21/2017 02:30 pm
What Gwen said was, "we're going to try to bring them back"..."we would eventually love to reuse them so you got to land them not in the water".

https://www.youtube.com/watch?v=xjXYSJF-7Cs?t=13m3s
Title: Re: Fairing reuse
Post by: Daniels30 on 02/21/2017 03:42 pm
Morning/Evening All,

This is regarding the Echostar-23 GTO Mission faring recovery plans.
As this is the first Faring recovery attempt SpaceX has planned i have been thinking on what risks may occur.
Firsty there's weight of the fairing. Presumably this has some kind of heat shield much like stage 1 uses and Dragon to re enter Earth's atmosphere. (obviously not orbital speeds but still a decent amount of velocity just over 9000 Km/H on the SES-9 mission)
There's also a potential for a parachute that would be mounted inside so that's a little more weight to cope with.
What measures would the pneumatically activated fairings clamps have to change in order to achieve sufficient clearance of stage 2? Would a higher pressure charge be adequate in removing the fairings and cleaning F9 safely.
I'd appreciate any responses from folks. 
Title: Re: Fairing reuse
Post by: cscott on 02/21/2017 04:12 pm
"land" makes it sound like mid-air recovery isn't the primary focus right now; they might try to catch it with an ASDS first.  Especially for Echostar, since the ASDS won't need to catch the booster.  We should keep an eye out for the ASDS leaving port.
Title: Re: Fairing reuse
Post by: nacnud on 02/21/2017 04:21 pm
I wonder if they could be recovered in a similar way to scaneagle by flying into a wire or net.

https://www.youtube.com/watch?v=NY1Y9LBATHo
Title: Re: Fairing reuse
Post by: getitdoneinspace on 02/21/2017 08:32 pm
I wonder if they could be recovered in a similar way to scaneagle by flying into a wire or net.

That is a very interesting idea. I wonder how much time would pass between the Falcon 9 landing on the ASDS and the two fairing halves arriving at the ASDS. Keying off the "Autonomous" word, just imagine immediately after the Falcon 9 lands a simple robot autonomously secures the rocket to the deck, while at the same time, two autonomous articulating boom lift type devices move to opposite edges of the ASDS and each position themselves to snag one of the fairing halves. The parafoil (para something ?) for each fairing would need to be very accurate, but I would guess this may be easier than landing the 1st stage.  ;)
Title: Re: Fairing reuse
Post by: Kaputnik on 02/21/2017 09:04 pm
I don't suppose anybody makes a drone that could catch a fairing half?
Title: Re: Fairing reuse
Post by: IanThePineapple on 02/21/2017 09:07 pm
I don't suppose anybody makes a drone that could catch a fairing half?

You'd need a BIG drone
Title: Re: Fairing reuse
Post by: matthewkantar on 02/21/2017 09:45 pm
just imagine immediately after the Falcon 9 lands a simple robot autonomously secures the rocket to the deck, while at the same time, two autonomous articulating boom lift type devices move to opposite edges of the ASDS and each position themselves to snag one of the fairing halves.

I think it would have to be a different ship. You would not want your safely landed ship getting kerblowed by an incoming fairing half.

Matthew
Title: Re: Fairing reuse
Post by: envy887 on 02/21/2017 10:34 pm
I don't suppose anybody makes a drone that could catch a fairing half?

There are some quite large "pilot optional" aircraft.
Title: Re: Fairing reuse
Post by: TrevorMonty on 02/22/2017 01:15 am
Midair recovery would require 2 helicopters or drones.
Title: Re: Fairing reuse
Post by: docmordrid on 02/22/2017 02:36 am
I don't suppose anybody makes a drone that could catch a fairing half?

You'd need a BIG drone

The K-MAX UAV chopper can carry 2.6 tonnes. Used in A'stan.

https://youtu.be/-4OyZZ71RqY

Title: Re: Fairing reuse
Post by: meberbs on 02/22/2017 03:58 am
I don't suppose anybody makes a drone that could catch a fairing half?

You'd need a BIG drone

The K-MAX UAV chopper can carry 2.6 tonnes. Used in A'stan.

https://www.youtube.com/watch?v=-4OyZZ71RqY
I had actually thought about the K-MAX as well. The K-MAX is actually a regular helicopter retrofitted to act as a UAV. It is probably cheaper to by the regular version (or some other manned helicopter) than pay Lockheed to convert one to a UAV. Also, the K-MAX UAV actually is very light itself, so it may not be best at dynamically grabbing a parachuting fairing.

Some other military drones also might have the payload capacity for a fairing, but again, I think it might actually be safer to go with larger aircraft.
Title: Re: Fairing reuse
Post by: Zed_Noir on 02/22/2017 04:05 am
Midair recovery would require 2 helicopters or drones.

Or better yet 2 V-22 Osprey VTOLs. Conventional Helos is relatively slow to transit to a parking orbit at a reasonably high altitude plus a low service ceiling and short range. IMO Helos might only get one shot per sortie to attempt a mid-air recovery of a payload fairing section. If they can be operated from a platform near the recovery site if the helos are not equipped with in-flight refueling.
Title: Re: Fairing reuse
Post by: meekGee on 02/22/2017 05:20 am
Can they fit two helicopters on the barge?  It halves the required range, and gets rid of endurance issues, since they only take off once the clamp release.

The helicopters should probably be unmanned, since if you have people on the barge at launch time, it complicates things...
Title: Re: Fairing reuse
Post by: cscott on 02/22/2017 03:05 pm
We've been over the mid-air recovery options before. It seems you are missing Gwynne's major hint: "land".  What are the possible options that she might call "landing"?
Title: Re: Fairing reuse
Post by: rsdavis9 on 02/22/2017 03:46 pm
I think catching them on the deck of a ship is a good possibility. They shouldn't be a risk to personnel on the ship. The fairings can move and steer and the ship can move and steer.
Title: Re: Fairing reuse
Post by: Semmel on 02/22/2017 05:22 pm
I think you all miss the unspoken 'eventually' here. Why assume a full fledged recovery procedure at the first try? It would be enough to just have glidechutes or parachutes dumping the fairing into the ocean. Maybe even for multiple flight just to make sure they understand the behaviour. Only then go out with a retrieval method.

Also it seems unlikely that the barge would be considered as a landing base since it might have a rocket sitting in the middle and no personal to handle the fairing half's after dump off. Not impossible but I would consider it unlikely.
Title: Re: Fairing reuse
Post by: SDSmith on 02/22/2017 05:31 pm
I think you all miss the unspoken 'eventually' here. Why assume a full fledged recovery procedure at the first try? It would be enough to just have glidechutes or parachutes dumping the fairing into the ocean. Maybe even for multiple flight just to make sure they understand the behaviour. Only then go out with a retrieval method.

Also it seems unlikely that the barge would be considered as a landing base since it might have a rocket sitting in the middle and no personal to handle the fairing half's after dump off. Not impossible but I would consider it unlikely.
Don't forget the fairing is quite large. The height is 43' (13.1m) x 17.1 ft (5.2m). 
Title: Re: Fairing reuse
Post by: envy887 on 02/22/2017 06:05 pm
We've been over the mid-air recovery options before. It seems you are missing Gwynne's major hint: "land".  What are the possible options that she might call "landing"?

The only option I can realistically envision is a large inflatable raft set up at specified GPS coordinates, with guided parachutes dropping the fairing halves on the coordinates and thus on the raft.

The fairings under chute would be moving pretty slowly, so they aren't real dangerous and the raft could be deployed and controlled by the ASDS support ships. The chutes should have enough cross-range to set up the raft ~10 km away from where a ballistic trajectory takes the fairings, so they don't crash into the raft or support ships in the event a chute fails to open or loses control.

IIRC the support ships already stand-off from the ASDS by about 10 km, and I've seen reports that they can see the fairings falling into the ocean. So the stand-off location can't be too far away from where the ballistic trajectory takes the fairings, but far enough to not get hit.
Title: Re: Fairing reuse
Post by: nacnud on 02/22/2017 06:13 pm
Any idea of the timing? I.E. Which lands first, the rocket or the fairing?
Title: Re: Fairing reuse
Post by: envy887 on 02/22/2017 06:51 pm
Any idea of the timing? I.E. Which lands first, the rocket or the fairing?

The fairings separate later and travel a lot slower through the atmosphere, so they will arrive later than the rocket.
Title: Re: Fairing reuse
Post by: nacnud on 02/22/2017 07:31 pm
Thanks, I thought so.
* So the barge is occupied, can't land there.
* The tug has people on, can't land there.
* The fairings are huge so mid air catching would be expensive if not impossible

Depending on the flight accuracy I wonder if you could use something like this to catch them just before they hit the water. Once the fairing is aboard they could also find lunch.
Title: Re: Fairing reuse
Post by: cscott on 02/22/2017 08:13 pm
ASDS isn't occupied for Echostar 23.  So they might well start with the large unmanned barge before trying something smaller.

Someone thought the fairings might have enough cross range to make Bermuda?
Title: Re: Fairing reuse
Post by: Lars-J on 02/22/2017 08:18 pm
ASDS isn't occupied for Echostar 23.  So they might well start with the large unmanned barge before trying something smaller.

Someone thought the fairings might have enough cross range to make Bermuda?

The first attempt will likely just be to parachute them into the ocean, for analysis. Then the next time they can improve the parachute landing accuracy, and the as a final step guide the parachute to a ship or an inflated surface in the water.

Imaging this inflated thing, but larger. ;)
Title: Re: Fairing reuse
Post by: QuantumG on 02/23/2017 12:19 am
The fairings are basically flying wings. I wouldn't be surprised if they were aiming to fly them all the way back to the launch site.
Title: Re: Fairing reuse
Post by: IanThePineapple on 02/23/2017 12:20 am
The fairings are basically flying wings. I wouldn't be surprised if they were aiming to fly them all the way back to the launch site.

Land them on the SLF  :)
Title: Re: Fairing reuse
Post by: Kaputnik on 02/23/2017 01:18 am
How far downrange will they be when they hit the atmosphere?
And does anyone know the airspeed velocity of an unladen payload fairing?
Title: Re: Fairing reuse
Post by: envy887 on 02/23/2017 03:21 am
The fairings separate after the booster does and are going downrange on the same ballistic arc. They splash hundreds of miles downrange and would need insane glide ratios to RTLS.

And no, they aren't doing a powered return.

Terminal velocity will depend a lot on exactly how heavy they are and what orientation they fall in, but 20 to 30 m/s is probably a good place to start. Chutes will cut that by 50-80%, maybe more.
Title: Re: Fairing reuse
Post by: Stan-1967 on 02/23/2017 04:11 am
How far downrange will they be when they hit the atmosphere?
And does anyone know the airspeed velocity of an unladen payload fairing?
Considering the fairings are made by RUAG Space,  we need to use the data tables for unladen European payload fairings. 
Title: Re: Fairing reuse
Post by: Lars-J on 02/23/2017 05:03 am
How far downrange will they be when they hit the atmosphere?
And does anyone know the airspeed velocity of an unladen payload fairing?
Considering the fairings are made by RUAG Space,  we need to use the data tables for unladen European payload fairings.

SpaceX makes their own fairings, but a goog joke nonetheless.  ;D (RUAG makes the Atlas V and Ariane V fairings)
Title: Re: Fairing reuse
Post by: woods170 on 02/23/2017 07:06 am
How far downrange will they be when they hit the atmosphere?
And does anyone know the airspeed velocity of an unladen payload fairing?
Considering the fairings are made by RUAG Space,  we need to use the data tables for unladen European payload fairings.

SpaceX makes their own fairings, but a goog joke nonetheless.  ;D (RUAG makes the Atlas V and Ariane V fairings)
Also, the SpaceX fairings are considerably more heavy than their RUAG counterparts given that the SpaceX fairings are structurally carrying the payload while the Atlas V and Ariane V fairings are not.
Title: Re: Fairing reuse
Post by: fast on 02/23/2017 07:23 am
Also, the SpaceX fairings are considerably more heavy than their RUAG counterparts given that the SpaceX fairings are structurally carrying the payload while the Atlas V and Ariane V fairings are not.

Is it even possible?
In this case I assume payload will have to separate from second stage together with fairing :)
Title: Re: Fairing reuse
Post by: Hobbes-22 on 02/23/2017 08:14 am
as far as I know, SpaceX use an interface ring on top of the second stage as the load-bearing element for the payload, just like everybody else?
Title: Re: Fairing reuse
Post by: cscott on 02/23/2017 12:55 pm
I think woods170 may be referring to loads during horizontal integration.
Title: Re: Fairing reuse
Post by: woods170 on 02/23/2017 01:06 pm
I think woods170 may be referring to loads during horizontal integration.
Correct.

See Jim's explanation of it here: https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561918#msg1561918 (https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561918#msg1561918)

And Joek's drawing of it here: https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561934#msg1561934 (https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561934#msg1561934)

And Jim's endorsement of Joek's drawing here: https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561969#msg1561969 (https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561969#msg1561969)

And this news article shows a rare image of an encapsulated payload going horizontal: https://www.noozhawk.com/noozhawk/print/falcon_9_rocket_moving_toward_nasa_launch_at_vandenberg_afb

You will notice that the payload and fairing are not held via the PAF (Payload Attachment Fitting), but via the fairing halves. Consequently, the load of the payload goes thru the fairing, not the PAF. This requires a strong fairing. Much stronger than those from RUAG et al.
Title: Re: Fairing reuse
Post by: Jim on 02/23/2017 01:06 pm
Also, the SpaceX fairings are considerably more heavy than their RUAG counterparts given that the SpaceX fairings are structurally carrying the payload while the Atlas V and Ariane V fairings are not.

Is it even possible?
In this case I assume payload will have to separate from second stage together with fairing :)

no, the adapter (with payload) stays with the second stage
Title: Re: Fairing reuse
Post by: Jim on 02/23/2017 01:08 pm
as far as I know, SpaceX use an interface ring on top of the second stage as the load-bearing element for the payload, just like everybody else?

no, there is an adapter between payload and stage, which the fairing also mates to
Title: Re: Fairing reuse
Post by: mrkmrsk on 02/23/2017 01:22 pm
And does anyone know the airspeed velocity of an unladen payload fairing?

African, or European?
Title: Re: Fairing reuse
Post by: JasonAW3 on 02/23/2017 01:45 pm
How far downrange will they be when they hit the atmosphere?
And does anyone know the airspeed velocity of an unladen payload fairing?
Considering the fairings are made by RUAG Space,  we need to use the data tables for unladen European payload fairings.

SpaceX makes their own fairings, but a goog joke nonetheless.  ;D (RUAG makes the Atlas V and Ariane V fairings)

So what's your favorite fairing color?
Title: Re: Fairing reuse
Post by: meekGee on 02/23/2017 02:28 pm
I think woods170 may be referring to loads during horizontal integration.
Correct.

See Jim's explanation of it here: https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561918#msg1561918 (https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561918#msg1561918)

And Joek's drawing of it here: https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561934#msg1561934 (https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561934#msg1561934)

And Jim's endorsement of Joek's drawing here: https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561969#msg1561969 (https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561969#msg1561969)

And this news article shows a rare image of an encapsulated payload going horizontal: https://www.noozhawk.com/noozhawk/print/falcon_9_rocket_moving_toward_nasa_launch_at_vandenberg_afb

You will notice that the payload and fairing are not held via the PAF (Payload Attachment Fitting), but via the fairing halves. Consequently, the load of the payload goes thru the fairing, not the PAF. This requires a strong fairing. Much stronger than those from RUAG et al.
The fairing doesn't carry the payload since it doesn't touch it.  At worst, during horizontal integration, the fairing half carries its own weight.

There was never a good explanation of why they are heavy, except perhaps the desire for them to survive reentry.
Title: Re: Fairing reuse
Post by: cscott on 02/23/2017 02:37 pm
[...]
And this news article shows a rare image of an encapsulated payload going horizontal: https://www.noozhawk.com/noozhawk/print/falcon_9_rocket_moving_toward_nasa_launch_at_vandenberg_afb

You will notice that the payload and fairing are not held via the PAF (Payload Attachment Fitting), but via the fairing halves. Consequently, the load of the payload goes thru the fairing, not the PAF. This requires a strong fairing. Much stronger than those from RUAG et al.
The fairing doesn't carry the payload since it doesn't touch it.  At worst, during horizontal integration, the fairing half carries its own weight.

There was never a good explanation of why they are heavy, except perhaps the desire for them to survive reentry.
This photo posted above by @woods170 is pretty definitive. The fairing is carrying the weight of the payload.
Title: Re: Fairing reuse
Post by: woods170 on 02/23/2017 02:43 pm
I think woods170 may be referring to loads during horizontal integration.
Correct.

See Jim's explanation of it here: https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561918#msg1561918 (https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561918#msg1561918)

And Joek's drawing of it here: https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561934#msg1561934 (https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561934#msg1561934)

And Jim's endorsement of Joek's drawing here: https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561969#msg1561969 (https://forum.nasaspaceflight.com/index.php?topic=39181.msg1561969#msg1561969)

And this news article shows a rare image of an encapsulated payload going horizontal: https://www.noozhawk.com/noozhawk/print/falcon_9_rocket_moving_toward_nasa_launch_at_vandenberg_afb (https://www.noozhawk.com/noozhawk/print/falcon_9_rocket_moving_toward_nasa_launch_at_vandenberg_afb)

You will notice that the payload and fairing are not held via the PAF (Payload Attachment Fitting), but via the fairing halves. Consequently, the load of the payload goes thru the fairing, not the PAF. This requires a strong fairing. Much stronger than those from RUAG et al.
The fairing doesn't carry the payload since it doesn't touch it.  At worst, during horizontal integration, the fairing half carries its own weight.

There was never a good explanation of why they are heavy, except perhaps the desire for them to survive reentry.
Did you bother to read the referenced posts from Jim and Joek?
The payload is attached to the PAF and the PAF is attached to the bottom of the fairing halves. However, SpaceX does not handle this entire assembly by grabbing hold of the (bottom of the) PAF, but by grabbing the fairing itself. Thus, the load exerted by the payload goes thru the fairing. This applies for all ground-handling sequences once the payload is encapsulated. Lifting, break-over to horizontal, lifting for mating with the launch vehicle. All those are done by grabbing the fairing, not the PAF.

Only times the PAF carries the payload are while vertical, and the PAF is sitting on either the encapsulation fixture or on top of the erected rocket. But in all break-over and horizontal operations the payload is carried by the fairing, via the PAF.
Title: Re: Fairing reuse
Post by: rsdavis9 on 02/23/2017 02:49 pm
But to be perfectly clear... :)

When the fairing is supported the load of the payload goes through the PAF and then to the fairing.
There is no direct connection between the payload and fairing.

Correct?
Title: Re: Fairing reuse
Post by: woods170 on 02/23/2017 02:52 pm
But to be perfectly clear... :)

When the fairing is supported the load of the payload goes through the PAF and then to the fairing.
There is no direct connection between the payload and fairing.

Correct?
Correct. See drawing from Joek below. It makes this perfectly clear. No direct connection between fairing and payload. Loadpath (indicated as red line in Joek's drawing) is from payload to PAF to fairing. Hoisting points are on the fairing only. Not on the PAF. So, in any hoisting operation of the encapsulated payload, the load of the payload goes thru the fairing, via the PAF.
Title: Re: Fairing reuse
Post by: Lee Jay on 02/23/2017 02:53 pm
There was never a good explanation of why they are heavy, except perhaps the desire for them to survive reentry.

Surviving the transition to supersonic and max-q are the reasons.  The thing is really large (it would easily swallow most people's entire living room), and max-q is a lot of force distributed over a lot of area.
Title: Re: Fairing reuse
Post by: woods170 on 02/23/2017 02:58 pm
There was never a good explanation of why they are heavy, except perhaps the desire for them to survive reentry.

Surviving the transition to supersonic and max-q are the reasons.  The thing is really large (it would easily swallow most people's entire living room), and max-q is a lot of force distributed over a lot of area.
No, not the real reason. Same forces apply to fairings from RUAG and other manufacturers. But those fairings are much lighter (mass-wise). Those fairings do not have to carry the payload mass during ground handling. Atlas 5 (for example) grabs the encapsulated payload via the PAF, not the fairing. Ariane 5 first has the PAF and payload integrated on the rocket, then places the fairing over them. Hence, those fairings only need to be strong enough to carry their own weight, unlike the F9 fairing.
Title: Re: Fairing reuse
Post by: cscott on 02/23/2017 03:54 pm
Granted, we haven't answered meekgee's "why" question yet.  Presumably at some early phase of design, SpaceX could have chosen to have hold the encapsulated payload by the PAF during horizontal processing. There would be a lot of cantilever forces, but I'd sure it would be technically possible.  They must have done some trade-off and determined that beefing up the payload fairing to carry the loads was worth it.  It is *possible* that thoughts about future reuse mechanisms for the fairing played some role in that decision.

IE, the "why" might be, "greatly simplifies handling during horizontal integration and the added structure can do double duty if we succeed in our reuse plans."  Much like with the sizing of the F9 first stage or the use of common fuels for S1 and S2, SpaceX appears not averse to giving up some performance (due extra fairing weight in this case) if it serves their bigger picture goals of streamlined manufacturing, rapid turnaround, and reuse.

But that's just speculation.
Title: Re: Fairing reuse
Post by: Semmel on 02/23/2017 04:06 pm
How do you mate an incapsulated payload fairing assembly with the second stage horizontally when you cannot grab the fairing? The only attachment points for the adapter is at the mating surface. I don't see how that can be done without adding a lot of mass to the adapter assembly. Remember, the heavy fairing gets off the rocket shortly after stage separation while the mass on the adapter goes to orbit. Maybe the reason the second stage including the adapter are so light is because the fairing is so heavy.

Also shines new light on the payload restrictions of about 10 T to the current payload. It was speculated that FH can not bring heavy payloads to LEO because the adapter is not capable to hold heavy loads. Maybe the adapter is not the limitation.. Maybe it's the fairing.
Title: Re: Fairing reuse
Post by: meekGee on 02/23/2017 06:14 pm
There was never a good explanation of why they are heavy, except perhaps the desire for them to survive reentry.

Surviving the transition to supersonic and max-q are the reasons.  The thing is really large (it would easily swallow most people's entire living room), and max-q is a lot of force distributed over a lot of area.

Yup. The diagram above is what I understand too.

My comments were regarding a) the payload not directly contact the fairing, and b) the fairing only holding the payload, while fully assembled, through the payload ring. (as shown).

In that case, the loading seems to me very similar to what a fairing normally experiences, or even more benign.

A closed fairing, while held at the payload ring, experiences (at the ring), torque to counteract:
- Its own mass, times any transverse acceleration during launch  (applied at the cg of the fairing)
- The aerodynamic pressure, sometimes while flying at an angle.  (applied closer to the tip of the fairing)

In the processing configuration, on the cart, it experience (at the ring), torque to counteract:
- The mass of the payload times the payload moment arm.

FWIW, if maxQ is about 30 kPa, and the fairing were to present an area of 15 m2 to the wind, that's 45 tons of force.

If transverse vibrations are, oh, 4 g max, then just the inertia of the fairing would add 16 tons, sideways.

Meanwhile, the whole satellite weighs, what, 4-5 tons?

So clearly the problem can't be at the ring.

What's left is the "eggshell", but if that was a problem, the cart would simply have a larger cradle - much easier than making the whole fairing 2x heavy just so the cradle can remain thin.


Long story short - I don't think it's the payload weight during handling.

I think a much likelier explanation is that the fairing has to take aerodynamic loads, WHILE IN TWO HALVES, during re-entry.  The half-fairing is a very weak physical structure compared to a closed fairing, and I think it the main reason for the extra mass.
Title: Re: Fairing reuse
Post by: Jim on 02/23/2017 06:18 pm
In that case, the loading seems to me very similar to what a fairing normally experiences, or even more benign.


It is nowhere near the same. On most other vehicles, the fairing never sees any loads from the payload. They could not be used in the same

Title: Re: Fairing reuse
Post by: meekGee on 02/23/2017 06:28 pm
In that case, the loading seems to me very similar to what a fairing normally experiences, or even more benign.


It is nowhere near the same. On most other vehicles, the fairing never sees any loads from the payload. They could not be used in the same

Just a matter of distributing the loads.  SpaceX clearly designed for this, but it shouldn't double the mass of the fairing.  Worst case they'd have added a ribbed structure from the support point to the payload ring, which would not weight multiple tons.  (And I don't think they needed to do that either).

What makes the SpaceX fairing twice as heavy as other fairings has to be a fairing-wide issue, and the only thing that fits the bill is either incompetence (they don't know how to build a lightweight fairing) or some unique aerodynamic requirements - and the second option is staring us right in the face, since we know they're trying recovery.


Title: Re: Fairing reuse
Post by: Jim on 02/23/2017 06:37 pm

FWIW, if maxQ is about 30 kPa, and the fairing were to present an area of 15 m2 to the wind, that's 45 tons of force.


That is an axial load and not the same as a side load
Title: Re: Fairing reuse
Post by: meekGee on 02/23/2017 06:40 pm

FWIW, if maxQ is about 30 kPa, and the fairing were to present an area of 15 m2 to the wind, that's 45 tons of force.


That is an axial load and not the same as a side load

True, but the rocket is designed to fly with an angle of attack, so there's a sideways component.  even 10% of 45 tons is comparable to the satellite, and that's on top of the dynamic loads.

Also - the moment arm is longer probably about twice of where the satellite CG is.
Title: Re: Fairing reuse
Post by: meberbs on 02/23/2017 06:43 pm
In that case, the loading seems to me very similar to what a fairing normally experiences, or even more benign.


It is nowhere near the same. On most other vehicles, the fairing never sees any loads from the payload. They could not be used in the same

Just a matter of distributing the loads.  SpaceX clearly designed for this, but it shouldn't double the mass of the fairing.  Worst case they'd have added a ribbed structure from the support point to the payload ring, which would not weight multiple tons.  (And I don't think they needed to do that either).

What makes the SpaceX fairing twice as heavy as other fairings has to be a fairing-wide issue, and the only thing that fits the bill is either incompetence (they don't know how to build a lightweight fairing) or some unique aerodynamic requirements - and the second option is staring us right in the face, since we know they're trying recovery.
Or a structural requirement. The pictures clearly show the fairing with enclosed payload being lifted by the middle of the fairing. From other's comments here, such an operation never happens with fairings for other rockets. SpaceX probably does this for some reason based on their processing flow (maybe not having to have special equipment to deal with the torque on the payload adapter before the adapter gets attached to the rocket.)

Aerodynamic concerns for recovery don't make sense, because information relating to fairing recovery has indicated that the current fairings were not designed for recovery. The current fairings were designed long before they would have been ready to seriously consider fairing recovery.

Also, you are really, really oversimplifying structural analysis in some of your posts.
Title: Re: Fairing reuse
Post by: meekGee on 02/23/2017 06:50 pm
In that case, the loading seems to me very similar to what a fairing normally experiences, or even more benign.


It is nowhere near the same. On most other vehicles, the fairing never sees any loads from the payload. They could not be used in the same

Just a matter of distributing the loads.  SpaceX clearly designed for this, but it shouldn't double the mass of the fairing.  Worst case they'd have added a ribbed structure from the support point to the payload ring, which would not weight multiple tons.  (And I don't think they needed to do that either).

What makes the SpaceX fairing twice as heavy as other fairings has to be a fairing-wide issue, and the only thing that fits the bill is either incompetence (they don't know how to build a lightweight fairing) or some unique aerodynamic requirements - and the second option is staring us right in the face, since we know they're trying recovery.
Or a structural requirement. The pictures clearly show the fairing with enclosed payload being lifted by the middle of the fairing. From other's comments here, such an operation never happens with fairings for other rockets. SpaceX probably does this for some reason based on their processing flow (maybe not having to have special equipment to deal with the torque on the payload adapter before the adapter gets attached to the rocket.)

Aerodynamic concerns for recovery don't make sense, because information relating to fairing recovery has indicated that the current fairings were not designed for recovery. The current fairings were designed long before they would have been ready to seriously consider fairing recovery.

Also, you are really, really oversimplifying structural analysis in some of your posts.

Of course I am...   I also don't have the details of their structure necessary to even start a more complex analysis....   But neither do the other posters...

All I'm saying is that the extra weight of the fairing (twice what a normal fairing would weigh) seems excessive for  the support outlined, since IMO at the worse case it would have been a small penalty, or more likely, none at all.

OTOH, those fairings are doing something else very differently from regular fairings.... trying to perform controlled re-entry...  so that should be the likely suspect.

As for when did SpaceX start thinking about fairing recovery - I don't know, and neither do you.  It's clearly not the final design, but whether they were built more robustly to enable even initial experimentation - we simply can't tell.  But probably earlier than a year ago...
Title: Re: Fairing reuse
Post by: Jim on 02/23/2017 06:53 pm

As for when did SpaceX start thinking about fairing recovery - I don't know, and neither do you.  It's clearly not the final design, but whether they were built more robustly to enable even initial experimentation - we simply can't tell.  But probably earlier than a year ago...


The fairing design predates the first launch
Title: Re: Fairing reuse
Post by: meekGee on 02/23/2017 07:36 pm

As for when did SpaceX start thinking about fairing recovery - I don't know, and neither do you.  It's clearly not the final design, but whether they were built more robustly to enable even initial experimentation - we simply can't tell.  But probably earlier than a year ago...


The fairing design predates the first launch

Why would that support your case?
Title: Re: Fairing reuse
Post by: Zed_Noir on 02/23/2017 08:02 pm
....

Also shines new light on the payload restrictions of about 10 T to the current payload. It was speculated that FH can not bring heavy payloads to LEO because the adapter is not capable to hold heavy loads. Maybe the adapter is not the limitation.. Maybe it's the fairing.

It will be interesting to see what the maximum payload will be for the FH when vertically integrated at LC-39A
Title: Re: Fairing reuse
Post by: Jim on 02/24/2017 02:06 am

As for when did SpaceX start thinking about fairing recovery - I don't know, and neither do you.  It's clearly not the final design, but whether they were built more robustly to enable even initial experimentation - we simply can't tell.  But probably earlier than a year ago...


The fairing design predates the first launch

Why would that support your case?

because nothing supports yours and the fairing supports the payload and that it why it is heavy.  There is no other US fairing that can support a payload in the same manner without major redesign.
Title: Re: Fairing reuse
Post by: meekGee on 02/24/2017 02:08 am

As for when did SpaceX start thinking about fairing recovery - I don't know, and neither do you.  It's clearly not the final design, but whether they were built more robustly to enable even initial experimentation - we simply can't tell.  But probably earlier than a year ago...


The fairing design predates the first launch

Why would that support your case?

because nothing supports yours and the fairing supports the payload and that it why it is heavy.  There is no other US fairing that can support a payload.
What I asked was why would the fact that the fairing design is old support your assertion.  You brought it up, not me.
Title: Re: Fairing reuse
Post by: Jim on 02/24/2017 02:08 am
....

Also shines new light on the payload restrictions of about 10 T to the current payload. It was speculated that FH can not bring heavy payloads to LEO because the adapter is not capable to hold heavy loads. Maybe the adapter is not the limitation.. Maybe it's the fairing.

It will be interesting to see what the maximum payload will be for the FH when vertically integrated at LC-39A

if it happens at all.
Title: Re: Fairing reuse
Post by: Semmel on 02/24/2017 11:50 am
....

Also shines new light on the payload restrictions of about 10 T to the current payload. It was speculated that FH can not bring heavy payloads to LEO because the adapter is not capable to hold heavy loads. Maybe the adapter is not the limitation.. Maybe it's the fairing.

It will be interesting to see what the maximum payload will be for the FH when vertically integrated at LC-39A

if it happens at all.

True. The primary customer for FH would be heavy GTO sats. These are not so heavy to exceed the GTO capacity of FH. So there would be no reason to update to vertical integration or new fairings that support heavier loads. Time will tell if SpaceX wants to launch heavy LEO payloads like bigelow modules and national security payloads.
Title: Re: Fairing reuse
Post by: watermod on 02/24/2017 12:59 pm
If it can be made/machined to size this new material (metal foam) might make a great next-gen faring.
http://www.foxnews.com/tech/2017/02/23/this-foam-stops-bullets-cold-and-pulverizes-them-to-dust.html (http://www.foxnews.com/tech/2017/02/23/this-foam-stops-bullets-cold-and-pulverizes-them-to-dust.html)
Title: Re: Fairing reuse
Post by: Doesitfloat on 02/24/2017 03:04 pm
This theory hasn't been mentioned yet so:
Spacex fairing are heavier because they use a less expensive but lower strength carbon fiber. The high strength aerospace carbon fiber is double to triple the cost of a utility strength fiber. In addition to ensure the higher strength the resin system is also more expensive. ( Resin system + manufacturing system)
Simply to get an equivalent strength out of lower strength fiber  there must be more... hence heavier.
But Cheaper
Title: Re: Fairing reuse
Post by: ennisj on 02/24/2017 07:15 pm
One other thing I haven't seen mentioned is that SpaceX uses a pneumatic system for fairing separation; everyone else (to my knowledge) uses pyrotechnics.

I can't imaging why that would double the weight though. But it is another difference.
Title: Re: Fairing reuse
Post by: AAPSkylab on 02/24/2017 07:34 pm
This theory hasn't been mentioned yet so:
Spacex fairing are heavier because they use a less expensive but lower strength carbon fiber. The high strength aerospace carbon fiber is double to triple the cost of a utility strength fiber. In addition to ensure the higher strength the resin system is also more expensive. ( Resin system + manufacturing system)
Simply to get an equivalent strength out of lower strength fiber  there must be more... hence heavier.
But Cheaper

Is this cheaper construction known as fact or is it speculation?

If this is true, could this mean that their intent is to research and develop fairing recovery and reuse while using this less expensive construction method.  After they succeed (if possible) then they could transfer their recovery tech to a more expensive but lighter construction method.  This way the recovery tech might not be a weight penalty and the ability to recover and reuse would mitigate the increased cost of construction.
Title: Re: Fairing reuse
Post by: Lar on 02/24/2017 08:02 pm
I like the idea that they built a cheap but heavy fairing .... knowing that eventually they would reengineer it with more expensive but lighter materials... more expensive ONCE, yes,  but since now it's recoverable (the mass savings is used for whatever the recovery mechanism is), actually LESS expensive iff they mostly get it back.

they were thinking ahead.

People focus on SpaceX changing plans but they miss that they also have been taking the long view here for a long time.

Also I don't see the need for a lot of heat shielding (said upthread a lot).... These have very low density so terminal velocity is low.
Title: Re: Fairing reuse
Post by: cscott on 02/24/2017 11:28 pm
I don't see any evidence they are using anything other than current state-of-the-art aerospace composites for the fairing.  Let's not pile speculation on speculation.
Title: Re: Fairing reuse
Post by: Lee Jay on 02/25/2017 12:20 am
I like the idea that they built a cheap but heavy fairing ....

What makes you think it's cheap?  Elon said it was "millions of dollars", which is quite a lot for a structure this size.
Title: Re: Fairing reuse
Post by: JamesH65 on 02/25/2017 05:24 pm
I don't see any evidence they are using anything other than current state-of-the-art aerospace composites for the fairing.  Let's not pile speculation on speculation.

Of course, there is no evidence they are using state of the art aerospace composites either...unless you want to assume/speculate that they are....;-)
Title: Re: Fairing reuse
Post by: cscott on 02/25/2017 06:27 pm
We know the original manufacturer of the fairings was doing current aerospace grade work.  You can speculate that SpaceX simplified or complexified things after they brought manufacturing in-house, but until they do a major fairing redesign Occam's razor would state they are still using something close to standard manufacturing practice for composites.

And SpaceX disclaims any craziness:
Quote
. The fairing is 13.1 meters (43 feet) high and 5.2 meters (17 feet) wide. It consists of an aluminum honeycomb core with carbon-fiber face sheets fabricated in two half-shells.
http://www.spacex.com/news/2013/04/12/fairing

Note: when I say "state-of-the-art" I mean, same as any other current manufacturer would use.  I'm not claiming super secret sauce or unicorn novelty.
Title: Re: Fairing reuse
Post by: Robotbeat on 02/25/2017 06:33 pm
Toray makes the best carbon fiber, bar none. They got a monopoly on the best stuff. But it's very, very difficult to get ahold of it if you aren't Boeing. You need an agreement with them, which SpaceX only recently got. Safe to say SpaceX has not been using Toray in the past.
Title: Re: Fairing reuse
Post by: DOCinCT on 02/25/2017 08:47 pm
Even though the fairing is somewhat constrained in terms of usable volume there are spaces available not normally assigned to payload as shown in the hatched area in the picture. If they went the parachute route, the spaces by the PAF seem most useful.
(Note:the heavy PAF can handle payloads up to 24,000 lb, far short of the FH throw wgt.)
Title: Re: Fairing reuse
Post by: Jim on 02/25/2017 11:23 pm
Fairing 2.0 will be a little different and slightly larger
Title: Re: Fairing reuse
Post by: Jcc on 02/25/2017 11:31 pm
Fairing 2.0 will be a little different and slightly larger

Do you have a source (and if so, please tell)?
Title: Re: Fairing reuse
Post by: cscott on 02/26/2017 12:43 am
Jim is a source.
Title: Re: Fairing reuse
Post by: meekGee on 02/26/2017 12:50 am
It'll be interesting to see how much it will weigh...

Though the principle of "performance loss for reusability" still applies.
Title: Re: Fairing reuse
Post by: envy887 on 02/26/2017 01:16 am
Any idea when this will be flying? Only on Heavy or on F9 also?
Title: Re: Fairing reuse
Post by: Jim on 02/26/2017 01:27 am

Though the principle of "performance loss for reusability" still applies.

The current fairing existed before thoughts of such
Title: Re: Fairing reuse
Post by: Jim on 02/26/2017 01:28 am
Any idea when this will be flying? Only on Heavy or on F9 also?

there isn't going to be a different fairing for the heavy
Title: Re: Fairing reuse
Post by: Lar on 02/26/2017 01:31 am
I like the idea that they built a cheap but heavy fairing ....

What makes you think it's cheap?  Elon said it was "millions of dollars", which is quite a lot for a structure this size.

two things....

1) it's an idea which I like but it's not necessarily my idea, I just like it. So ask the originator.
2) cheap is a relative term. If they aren't using buckyballs in it, or unobtanium or whatever, it's cheaper than if they were.

Any idea when this will be flying? Only on Heavy or on F9 also?

there isn't going to be a different fairing for the heavy

Which I guess means that FH will be volume limited in many cases before it is mass limited?
Title: Re: Fairing reuse
Post by: cppetrie on 02/26/2017 02:03 am
In that case, the loading seems to me very similar to what a fairing normally experiences, or even more benign.


It is nowhere near the same. On most other vehicles, the fairing never sees any loads from the payload. They could not be used in the same

Just a matter of distributing the loads.  SpaceX clearly designed for this, but it shouldn't double the mass of the fairing.  Worst case they'd have added a ribbed structure from the support point to the payload ring, which would not weight multiple tons.  (And I don't think they needed to do that either).

What makes the SpaceX fairing twice as heavy as other fairings has to be a fairing-wide issue, and the only thing that fits the bill is either incompetence (they don't know how to build a lightweight fairing) or some unique aerodynamic requirements - and the second option is staring us right in the face, since we know they're trying recovery.
Or a structural requirement. The pictures clearly show the fairing with enclosed payload being lifted by the middle of the fairing. From other's comments here, such an operation never happens with fairings for other rockets. SpaceX probably does this for some reason based on their processing flow (maybe not having to have special equipment to deal with the torque on the payload adapter before the adapter gets attached to the rocket.)

Aerodynamic concerns for recovery don't make sense, because information relating to fairing recovery has indicated that the current fairings were not designed for recovery. The current fairings were designed long before they would have been ready to seriously consider fairing recovery.

Also, you are really, really oversimplifying structural analysis in some of your posts.

Of course I am...   I also don't have the details of their structure necessary to even start a more complex analysis....   But neither do the other posters...

All I'm saying is that the extra weight of the fairing (twice what a normal fairing would weigh) seems excessive for  the support outlined, since IMO at the worse case it would have been a small penalty, or more likely, none at all.

OTOH, those fairings are doing something else very differently from regular fairings.... trying to perform controlled re-entry...  so that should be the likely suspect.

As for when did SpaceX start thinking about fairing recovery - I don't know, and neither do you.  It's clearly not the final design, but whether they were built more robustly to enable even initial experimentation - we simply can't tell.  But probably earlier than a year ago...

First post to NSF so forgive the likely uninformed intrusion on a long-running discussion, but what if the reasoning for the heavier fairing design was as follows: by integrating structural support for the payload during launch and MaxQ into the fairing rather than the payload adapter it allows them to jettison the weight of said support when fairing separation occurs meaning less weight is riding on stage 2 afterwards. If all the support is in the payload adapter, then you haul that and it's extra weight all the way out to your destination. Does the SpaceX fairing design allow a lighter payload adapter that is consequently lighter. I've not seen anything in the discussions I've visited thus far indicating one way or the other. Anyone with some insight that can chime in on the hypothesis I put forward?


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Title: Re: Fairing reuse
Post by: woods170 on 02/26/2017 10:22 am
First post to NSF so forgive the likely uninformed intrusion on a long-running discussion, but what if the reasoning for the heavier fairing design was as follows: by integrating structural support for the payload during launch and MaxQ into the fairing rather than the payload adapter it allows them to jettison the weight of said support when fairing separation occurs meaning less weight is riding on stage 2 afterwards. If all the support is in the payload adapter, then you haul that and it's extra weight all the way out to your destination. Does the SpaceX fairing design allow a lighter payload adapter that is consequently lighter. I've not seen anything in the discussions I've visited thus far indicating one way or the other. Anyone with some insight that can chime in on the hypothesis I put forward?


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Welcome to the forum.
The fairing only supports the payload, via the PAF, during ground handling: rotation from vertical to horizontal, any horizontal handling and horizontal integration onto the rocket. Payload mass throughout launch and MaxQ is supported by the upper stage, via the PAF.
Title: Re: Fairing reuse
Post by: DOCinCT on 02/26/2017 02:59 pm
...Does the SpaceX fairing design allow a lighter payload adapter that is consequently lighter. I've not seen anything in the discussions I've visited thus far indicating one way or the other. Anyone with some insight that can chime in on the hypothesis I put forward?
Sent from my iPhone using Tapatalk
The Payload Adapter Fitting (PAF) comes in two standard versions: the light PAF payloads weighing up to 3,453 kg (7,612 lb), and  the heavy PAF up to 10,886 kg (24,000 lb). 
Title: Re: Fairing reuse
Post by: cppetrie on 02/26/2017 05:09 pm
...Does the SpaceX fairing design allow a lighter payload adapter that is consequently lighter. I've not seen anything in the discussions I've visited thus far indicating one way or the other. Anyone with some insight that can chime in on the hypothesis I put forward?
Sent from my iPhone using Tapatalk
The Payload Adapter Fitting (PAF) comes in two standard versions: the light PAF payloads weighing up to 3,453 kg (7,612 lb), and  the heavy PAF up to 10,886 kg (24,000 lb).

Those are the weight limits for PAFs, but how do the weights of the PAFs themselves compare to PAFs of other launch vehicles with similar weight capacities?


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Title: Re: Fairing reuse
Post by: cppetrie on 02/26/2017 05:14 pm
First post to NSF so forgive the likely uninformed intrusion on a long-running discussion, but what if the reasoning for the heavier fairing design was as follows: by integrating structural support for the payload during launch and MaxQ into the fairing rather than the payload adapter it allows them to jettison the weight of said support when fairing separation occurs meaning less weight is riding on stage 2 afterwards. If all the support is in the payload adapter, then you haul that and it's extra weight all the way out to your destination. Does the SpaceX fairing design allow a lighter payload adapter that is consequently lighter. I've not seen anything in the discussions I've visited thus far indicating one way or the other. Anyone with some insight that can chime in on the hypothesis I put forward?


Sent from my iPhone using Tapatalk
Welcome to the forum.
The fairing only supports the payload, via the PAF, during ground handling: rotation from vertical to horizontal, any horizontal handling and horizontal integration onto the rocket. Payload mass throughout launch and MaxQ is supported by the upper stage, via the PAF.

That would seems to disprove my hypothesis. Are other launch vehicles with lighter fairings only vertically integrated? Could SpaceX have made a compromise on fairing weight in order to permit horizontal integration rather than vertical? Is there an advantage in terms of rocket design or launch prep to be able to integrate horizontally?


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Title: Re: Fairing reuse
Post by: envy887 on 02/26/2017 07:38 pm
Any idea when this will be flying? Only on Heavy or on F9 also?

there isn't going to be a different fairing for the heavy

Is it related to one of the upcoming F9 blocks?
Title: Re: Fairing reuse
Post by: RoboGoofers on 03/15/2017 03:50 pm
[...]
And this news article shows a rare image of an encapsulated payload going horizontal: https://www.noozhawk.com/noozhawk/print/falcon_9_rocket_moving_toward_nasa_launch_at_vandenberg_afb

You will notice that the payload and fairing are not held via the PAF (Payload Attachment Fitting), but via the fairing halves. Consequently, the load of the payload goes thru the fairing, not the PAF. This requires a strong fairing. Much stronger than those from RUAG et al.
The fairing doesn't carry the payload since it doesn't touch it.  At worst, during horizontal integration, the fairing half carries its own weight.

There was never a good explanation of why they are heavy, except perhaps the desire for them to survive reentry.
This photo posted above by @woods170 is pretty definitive. The fairing is carrying the weight of the payload.

Are the payloads designed to be positioned with a specific CG inside the fairing? The picture shows it perfectly balanced, but the lift points don't look repositionable, so it's not clear how they deal with different payload sizes and masses. Maybe they add ballast to 'even out the scales'?
Title: Re: Fairing reuse
Post by: Jim on 03/15/2017 03:54 pm

Are the payloads designed to be positioned with a specific CG inside the fairing? The picture shows it perfectly balanced, but the lift points don't look repositionable, so it's not clear how they deal with different payload sizes and masses. Maybe they add ballast to 'even out the scales'?

There are two cranes in use.  One is attached to the aft of the fairing.
Title: Re: Fairing reuse
Post by: RoboGoofers on 03/15/2017 05:00 pm

Are the payloads designed to be positioned with a specific CG inside the fairing? The picture shows it perfectly balanced, but the lift points don't look repositionable, so it's not clear how they deal with different payload sizes and masses. Maybe they add ballast to 'even out the scales'?

There are two cranes in use.  One is attached to the aft of the fairing.

Ok I see it now. I guess it's those spiderweb-y looking lines, and maybe that blue square.

Regarding mid-air capture; has anything as large as a F9 fairing been caught mid-air before? I'd imagine its shape would make it whip around a lot behind a plane or below a helicopter.
Title: Re: Fairing reuse
Post by: Alastor on 03/15/2017 09:05 pm
Some helicopter pilots on the forum have estimated that it would be a delicate operation, but possible.
Their main concern is actually the range of the helicopters.

As for slowing down the fairing, it's a matter of flying in formation with it, grab it and then slowly enough decelerate it. As for the weight itself, there are some pretty heavy lift helicopters around. That shouldn't be a problem in itself.
Title: Re: Fairing reuse
Post by: IanThePineapple on 03/15/2017 09:12 pm
The fact that CCAFS is an air force base should fare well for helicopters catching fairings
Title: Re: Fairing reuse
Post by: leetdan on 03/15/2017 09:21 pm
The fact that CCAFS is an air force base should fare well for helicopters catching fairings

Specifically, CCAFS and the 920th Rescue Wing (HC-130P, HH-60G) are both headquartered at nearby Patrick AFB.
Title: Re: Fairing reuse
Post by: mme on 03/15/2017 09:41 pm
The fact that CCAFS is an air force base should fare well for helicopters catching fairings

Specifically, CCAFS and the 920th Rescue Wing (HC-130P, HH-60G) are both headquartered at nearby Patrick AFB.
Yeah, but it's not like SpaceX is going to use military assets to recover fairings.
Title: Re: Fairing reuse
Post by: Kaputnik on 03/15/2017 09:58 pm
Range does seem to be the killer for helicopter recovery.
I guess you could snag the fairing halves using a fixed wing, then tow them back home, release and catch with a chopper. A bit Rube Goldberg though...
Title: Re: Fairing reuse
Post by: manoweb on 03/15/2017 10:38 pm
Honestly I would be very surprised if SpaceX wants to recover the fairings, for the sole purpose of saving money, by catching them on the fly with (military) helicopters. In my opinion they will come out with something much less expensive, even if it will take some time to develop the technology to do so
Title: Re: Fairing reuse
Post by: Jim on 03/16/2017 02:15 am
The fact that CCAFS is an air force base should fare well for helicopters catching fairings

It has no bearing on the matter.
Title: Re: Fairing reuse
Post by: Hobbes-22 on 03/16/2017 08:33 am
Honestly I would be very surprised if SpaceX wants to recover the fairings, for the sole purpose of saving money, by catching them on the fly with (military) helicopters. In my opinion they will come out with something much less expensive, even if it will take some time to develop the technology to do so

A helicopter capable of lifting the fairing can be rented for a few thousand/hour. Not cheap, but not prohibitively expensive either if the potential savings is $2M.
Title: Re: Fairing reuse
Post by: D_Dom on 03/16/2017 03:15 pm
Lifting the fairing does not seem to me nearly as challenging as catching one on the fly.
Title: Re: Fairing reuse
Post by: meekGee on 03/16/2017 05:08 pm
Lifting the fairing does not seem to me nearly as challenging as catching one on the fly.

True, but ironically, the same helicopter that can catch a fairing may not be able to take off with one...

Fuel weight is a big deal for helicopters in long range operations. 

Also, the weight you can carry while move forward is higher than what you can carry while hovering, so a helicopter may grab a fairing, and actually not be able to set it down, until later, when it burned off the rest of its fuel.

Ah, but at sea level you get more lift than at whatever altitude they'll be catching them at.  But then Florida air may be warmer.  Helicopters are a pain in the a**.
Title: Re: Fairing reuse
Post by: envy887 on 03/16/2017 06:01 pm
Why would they use precision GPS-guided chutes if they were going after them with a helo? The whole point of guidance is to drop them somewhere specific.
Title: Re: Fairing reuse
Post by: Kaputnik on 03/16/2017 06:29 pm
If helicopters are out of the question, the only feasible alternative that I can think of is parachuting down onto a huge inflatable raft. But it really would need to be impressively large- precision airdrops are only 50m accurate and I'm sure that's with a relatively dense and sturdy crate as cargo, not a big floppy fairing half that catches the wind and probably needs a low impact speed.

You have to wonder how they would then retrieve the fairing from within the raft, which would need to be very soft to act as any kind of a cushion.

It will be fascinating to see how they are going to do this.
Title: Re: Fairing reuse
Post by: Lar on 03/16/2017 06:52 pm
The fact that CCAFS is an air force base should fare well for helicopters catching fairings

Specifically, CCAFS and the 920th Rescue Wing (HC-130P, HH-60G) are both headquartered at nearby Patrick AFB.
Yeah, but it's not like SpaceX is going to use military assets to recover fairings.
Yeah, but that part of FL is pretty nice to live in, and ex Air Force helo drivers[1] that are hot shots might be fairly easy to find around there since they might want to retire there after 20 in the AF and out... So kind of using military SURPLUS assets, as it were. :)

1 - not that I know anyone like that.
Title: Re: Fairing reuse
Post by: Zed_Noir on 03/17/2017 09:50 pm
Lifting the fairing does not seem to me nearly as challenging as catching one on the fly.

True, but ironically, the same helicopter that can catch a fairing may not be able to take off with one...

Fuel weight is a big deal for helicopters in long range operations. 

Also, the weight you can carry while move forward is higher than what you can carry while hovering, so a helicopter may grab a fairing, and actually not be able to set it down, until later, when it burned off the rest of its fuel.

Ah, but at sea level you get more lift than at whatever altitude they'll be catching them at.  But then Florida air may be warmer.  Helicopters are a pain in the a**.

Just fitted an inflight refueling kit on the helicopter. So it isn't carrying a lot of fuel during the recovery, then top up after recovery.
Title: Re: Fairing reuse
Post by: Robotbeat on 03/18/2017 01:24 am
Oh great, inflight refueling...

This is looking more and more like a bad idea.
Title: Re: Fairing reuse
Post by: dorkmo on 03/18/2017 05:00 am
ignoring all the cons, would in-air recovery be the least stressful option on the fairing structure? or does it not even have that going for it?
Title: Re: Fairing reuse
Post by: Kaputnik on 03/18/2017 06:23 am
ignoring all the cons, would in-air recovery be the least stressful option on the fairing structure? or does it not even have that going for it?

It can be pretty gentle. The aircraft matches velocity with the target and then decelerates it gradually.
Title: Re: Fairing reuse
Post by: Hobbes-22 on 03/18/2017 09:56 am
ignoring all the cons, would in-air recovery be the least stressful option on the fairing structure? or does it not even have that going for it?

US armed forces and CIA use the Fulton (https://en.wikipedia.org/wiki/Fulton_surface-to-air_recovery_system) surface-to-air recovery system to pick up people from the ground without landing. An agent behind enemy lines launches a balloon with a line attached to it. A C-130 flies over, snatches the line and then reels in the agent. By using a long line, the acceleration load on the agent was limited, "the person being picked up experienced less of a shock than during a parachute opening."

So even with a fixed-wing aircraft, this recovery method can be made survivable for humans and other fragile loads.
Title: Re: Fairing reuse
Post by: Zed_Noir on 03/18/2017 02:00 pm
Oh great, inflight refueling...

This is looking more and more like a bad idea.

Most of the combat SAR helos of the USAF are already equipped with the inflight refueling kit. They need it for extended operational radius and/or time on station. 
Title: Re: Fairing reuse
Post by: JamesH65 on 03/18/2017 02:50 pm
Oh great, inflight refueling...

This is looking more and more like a bad idea.

Most of the combat SAR helos of the USAF are already equipped with the inflight refueling kit. They need it for extended operational radius and/or time on station.

They have unlimited cash, and own the refueling tankers...and they ain't cheap.
Title: Re: Fairing reuse
Post by: meekGee on 03/18/2017 03:50 pm
Oh great, inflight refueling...

This is looking more and more like a bad idea.

Most of the combat SAR helos of the USAF are already equipped with the inflight refueling kit. They need it for extended operational radius and/or time on station.

They have unlimited cash, and own the refueling tankers...and they ain't cheap.
Heli-on-barge is an option to consider, since it eliminates half the range, and maybe the whole "fly out before launch" thing.

If the fairing ends up close enough to the barge, the helicopter might take off only after launch.

(On RTLS launches, there isn't even a conflict)
Title: Re: Fairing reuse
Post by: chalz on 03/18/2017 10:31 pm
Not to state the obvious too much but since fairings come in halves all these special operations have to be done twice and simultaneously. This makes catching it look daunting. Two barges, two landing pads, two refuelling ops, two specialist pilots. How close could the Heli's get to each other? And what happens if you only catch one, how useful would it be without its partner?
Title: Re: Fairing reuse
Post by: meekGee on 03/19/2017 12:53 am
Not to state the obvious too much but since fairings come in halves all these special operations have to be done twice and simultaneously. This makes catching it look daunting. Two barges, two landing pads, two refuelling ops, two specialist pilots. How close could the Heli's get to each other? And what happens if you only catch one, how useful would it be without its partner?
Yup, from day one, the helicopter side seems very very difficult.

Unless they are unmanned, it pushes every edge of the envelope, and as you point out, including safety.

But clearly SpaceX has some plan in mind.  Hope we find out soon.
Title: Re: Fairing reuse
Post by: Zed_Noir on 03/19/2017 01:48 pm
After some thinking. Maybe SX will just added a parachute with radar transponder and some floatation devices to the PLF. Then fished the 2 PLF halves out of the water with a crane. Might need a couple of spotter aircraft to tracked the PLF descends and maintained visual contact until recovery assets are on the scene.
Title: Re: Fairing reuse
Post by: guckyfan on 03/19/2017 07:01 pm
After some thinking. Maybe SX will just added a parachute with radar transponder and some floatation devices to the PLF. Then fished the 2 PLF halves out of the water with a crane. Might need a couple of spotter aircraft to tracked the PLF descends and maintained visual contact until recovery assets are on the scene.

Sounds reasonable but Gwynne Shotwell said in her LC-39A interview that they don't want the fairing to get wet. Which surprised me somewhat.
Title: Re: Fairing reuse
Post by: Bargemanos on 03/19/2017 09:08 pm
After some thinking. Maybe SX will just added a parachute with radar transponder and some floatation devices to the PLF. Then fished the 2 PLF halves out of the water with a crane. Might need a couple of spotter aircraft to tracked the PLF descends and maintained visual contact until recovery assets are on the scene.
Sounds reasonable but Gwynne Shotwell said in her LC-39A interview that they don't want the fairing to get wet. Which surprised me somewhat.
Encapsulate just before splash down? Somewhat like the mars rovers.

Or is it possible to use the gliding shape of the half fairing to slow down speed enough to splash down real gently. Maby with the use of droge chutes for stability and if needed main chutes to slow down even further
Title: Re: Fairing reuse
Post by: matthewkantar on 03/19/2017 09:36 pm
SpaceX has stated the fairing are not going in the water.

Matthew
Title: Re: Fairing reuse
Post by: Space Ghost 1962 on 03/19/2017 09:42 pm
They aren't intended for immersion. You'll have to get them w/o reaching the water.

Which means either airborne recovery e.g. snag them with a drone, not unlike with Smart recovery, or you fly them back to land, and somehow recover them.
Title: Re: Fairing reuse
Post by: envy887 on 03/19/2017 11:58 pm
They aren't intended for immersion. You'll have to get them w/o reaching the water.

Which means either airborne recovery e.g. snag them with a drone, not unlike with Smart recovery, or you fly them back to land, and somehow recover them.

Or land them on something floating on the water.
Title: Re: Fairing reuse
Post by: meekGee on 03/20/2017 12:43 am
They aren't intended for immersion. You'll have to get them w/o reaching the water.

Which means either airborne recovery e.g. snag them with a drone, not unlike with Smart recovery, or you fly them back to land, and somehow recover them.

Or land them on something floating on the water.

To the extent that they can remain "dry", in wave action, salt spray, etc.

And that bouncing around on the waves doesn't exceed structural limits, or that at least such issues can be identified afterwards.
Title: Re: Fairing reuse
Post by: Lars-J on 03/20/2017 03:39 am
They aren't intended for immersion. You'll have to get them w/o reaching the water.

Which means either airborne recovery e.g. snag them with a drone, not unlike with Smart recovery, or you fly them back to land, and somehow recover them.

Or the third option (most likely IMO), precision land them on a barge or boat.
Title: Re: Fairing reuse
Post by: ChrisWilson68 on 03/20/2017 07:21 am
They aren't intended for immersion. You'll have to get them w/o reaching the water.

Which means either airborne recovery e.g. snag them with a drone, not unlike with Smart recovery, or you fly them back to land, and somehow recover them.

Or the third option (most likely IMO), precision land them on a barge or boat.

Then, just refuel them and let them fly themselves back to the launch site.
Title: Re: Fairing reuse
Post by: Kaputnik on 03/20/2017 09:17 pm
In the absence of better information we are going round and round in circles here. I think that every possibility has been suggested by somebody at some point. By way of recap, I think these are:
- mid air recovery by long range helo
- mid air recovery by short range ship based helo
- unmanned variant of the above
- mid air recovery by fixed wing aircraft with handover to helo for landing
- precision touchdown on ship/barge
- precision touchdown on inflatable raft
- modified PLF with aerodynamic control surfaces for flyback

The fascinating thing is that *all* of these options can be discounted as unworkable for various reasons.
Have I missed any off the list?
Title: Re: Fairing reuse
Post by: Lars-J on 03/20/2017 10:00 pm
In the absence of better information we are going round and round in circles here. I think that every possibility has been suggested by somebody at some point. By way of recap, I think these are:
- mid air recovery by long range helo
- mid air recovery by short range ship based helo
- unmanned variant of the above
- mid air recovery by fixed wing aircraft with handover to helo for landing
- precision touchdown on ship/barge
- precision touchdown on inflatable raft
- modified PLF with aerodynamic control surfaces for flyback

The fascinating thing is that *all* of these options can be discounted as unworkable for various reasons.
Have I missed any off the list?

How in the world is precision touchdown on ship/barge/raft unworkable?
Title: Re: Fairing reuse
Post by: docmordrid on 03/21/2017 12:44 am
In the absence of better information we are going round and round in circles here. I think that every possibility has been suggested by somebody at some point. By way of recap, I think these are:
- mid air recovery by long range helo
- mid air recovery by short range ship based helo
- unmanned variant of the above
- mid air recovery by fixed wing aircraft with handover to helo for landing
- precision touchdown on ship/barge
- precision touchdown on inflatable raft
- modified PLF with aerodynamic control surfaces for flyback

The fascinating thing is that *all* of these options can be discounted as unworkable for various reasons.
Have I missed any off the list?

How in the world is precision touchdown on ship/barge/raft unworkable?

Airborne Systems Dragonfly precision drop system, good for 10,000 lbs, only specs a 250m accuracy.

http://airborne-sys.com/wp-content/uploads/2016/08/ASG-DragonFly-20170206-English.pdf
Title: Re: Fairing reuse
Post by: ChrisC on 03/21/2017 02:19 am
In the absence of better information we are going round and round in circles here. I think that every possibility has been suggested by somebody at some point.

And we will again in about two weeks.  Wash, rinse, repeat until more facts come in.  See you in April.
Title: Re: Fairing reuse
Post by: meekGee on 03/21/2017 05:23 am
In the absence of better information we are going round and round in circles here. I think that every possibility has been suggested by somebody at some point. By way of recap, I think these are:
- mid air recovery by long range helo
- mid air recovery by short range ship based helo
- unmanned variant of the above
- mid air recovery by fixed wing aircraft with handover to helo for landing
- precision touchdown on ship/barge
- precision touchdown on inflatable raft
- modified PLF with aerodynamic control surfaces for flyback

The fascinating thing is that *all* of these options can be discounted as unworkable for various reasons.
Have I missed any off the list?
You can add long line dropoff from fixed wing aircraft. I don't think it was ever tried with something this big tho
Title: Re: Fairing reuse
Post by: JamesH65 on 03/21/2017 09:24 am
Anyone have any guesses on what the glide angle of a fairing is? Perhaps with fins/winglets? And how far downrange are they released, and how fast are they going at release?
Title: Re: Fairing reuse
Post by: Kaputnik on 03/21/2017 11:22 am
In the absence of better information we are going round and round in circles here. I think that every possibility has been suggested by somebody at some point. By way of recap, I think these are:
- mid air recovery by long range helo
- mid air recovery by short range ship based helo
- unmanned variant of the above
- mid air recovery by fixed wing aircraft with handover to helo for landing
- precision touchdown on ship/barge
- precision touchdown on inflatable raft
- modified PLF with aerodynamic control surfaces for flyback

The fascinating thing is that *all* of these options can be discounted as unworkable for various reasons.
Have I missed any off the list?
You can add long line dropoff from fixed wing aircraft. I don't think it was ever tried with something this big tho

How does that work? Do you reel it out realky fast, to negate airspeed, or do you fly a circle with a long tow?
Title: Re: Fairing reuse
Post by: Kaputnik on 03/21/2017 11:28 am
Anyone have any guesses on what the glide angle of a fairing is? Perhaps with fins/winglets? And how far downrange are they released, and how fast are they going at release?

I can't put any number to this right now (making it opinion rather than analysis) but I think the terminal velocity of a fairing half will be pretty low, making for a slow glide and a short range. Also, they are released ahortly after staging and will continue up on a ballistic trajectory alongside the first stage, making entry at a similar distance downrange (they are too high in the atmosphere, I think, to be able to make any aerodynamic manoeuvres).
So, if y are wondering whether the fairing halves would be able to glide back towards to the landing site for easier helo recovery, the answer is probably no.
Title: Re: Fairing reuse
Post by: meekGee on 03/21/2017 01:51 pm
In the absence of better information we are going round and round in circles here. I think that every possibility has been suggested by somebody at some point. By way of recap, I think these are:
- mid air recovery by long range helo
- mid air recovery by short range ship based helo
- unmanned variant of the above
- mid air recovery by fixed wing aircraft with handover to helo for landing
- precision touchdown on ship/barge
- precision touchdown on inflatable raft
- modified PLF with aerodynamic control surfaces for flyback

The fascinating thing is that *all* of these options can be discounted as unworkable for various reasons.
Have I missed any off the list?
You can add long line dropoff from fixed wing aircraft. I don't think it was ever tried with something this big tho

How does that work? Do you reel it out realky fast, to negate airspeed, or do you fly a circle with a long tow?
The latter.

Long line, draggy device, fly in a circle.

Legend has it that you can hand pick mail that way, but legends are famously exaggerated....

And it's a hypothetical, I don't think that's really in the plan.
Title: Re: Fairing reuse
Post by: LouScheffer on 03/21/2017 02:48 pm
In the absence of better information we are going round and round in circles here. I think that every possibility has been suggested by somebody at some point. By way of recap, I think these are:
- mid air recovery by long range helo
- mid air recovery by short range ship based helo
- unmanned variant of the above
- mid air recovery by fixed wing aircraft with handover to helo for landing
- precision touchdown on ship/barge
- precision touchdown on inflatable raft
- modified PLF with aerodynamic control surfaces for flyback

The fascinating thing is that *all* of these options can be discounted as unworkable for various reasons.
Have I missed any off the list?
How in the world is precision touchdown on ship/barge/raft unworkable?
Airborne Systems Dragonfly precision drop system, good for 10,000 lbs, only specs a 250m accuracy.
http://airborne-sys.com/wp-content/uploads/2016/08/ASG-DragonFly-20170206-English.pdf
But parachutes can be much more accurate.  Parachute landing competitions (http://www.fai.org/ipc-our-sport/accuracy-landing-freefall-style) have accuracies in the low cm range (they don't even record above 16cm, which is considered a complete miss).  So I would not rule this one out, if SpaceX cares to put some work into landing accuracy.
Title: Re: Fairing reuse
Post by: Swoopert on 03/21/2017 04:19 pm
But parachutes can be much more accurate.  Parachute landing competitions (http://www.fai.org/ipc-our-sport/accuracy-landing-freefall-style) have accuracies in the low cm range (they don't even record above 16cm, which is considered a complete miss).  So I would not rule this one out, if SpaceX cares to put some work into landing accuracy.

The types of parachute used for accuracy landing competitions are distinctly unsuited to these purposes. They are designed to open at very low speed, come in at an extremely steep glide angle, and require a very small range of wind conditions (usually less than 10-15kts and steady) to achieve that level of accuracy, which you're unlikely to see in the middle of the ocean where the fairings will end up due to the poor glide angle.

Swoopert.

2-time British Collegiate Parachute Accuracy champion
Title: Re: Fairing reuse
Post by: Kaputnik on 03/21/2017 04:55 pm
Another one to suggest and instantly dismiss:
Steerable foil landing on a moving platform (the idea being that the moving platform, e.g. a ship with a cushion on its aft deck, or towing an inflatable raft) can compensate somewhat for the inaccuracy of the incoming fairing.
Having seen an episode of Top Gear where they tried landing a parachutist in the back of a moving car, it seems that moving the landing target only makes things much harder...
Title: Re: Fairing reuse
Post by: LouScheffer on 03/21/2017 04:59 pm
But parachutes can be much more accurate.  Parachute landing competitions (http://www.fai.org/ipc-our-sport/accuracy-landing-freefall-style) have accuracies in the low cm range (they don't even record above 16cm, which is considered a complete miss).  So I would not rule this one out, if SpaceX cares to put some work into landing accuracy.

The types of parachute used for accuracy landing competitions are distinctly unsuited to these purposes. They are designed to open at very low speed, come in at an extremely steep glide angle, and require a very small range of wind conditions (usually less than 10-15kts and steady) to achieve that level of accuracy, which you're unlikely to see in the middle of the ocean where the fairings will end up due to the poor glide angle.

Swoopert.

2-time British Collegiate Parachute Accuracy champion
I certainly agree you could not use the type of parachute used in accuracy contests, but you don't need cm class accuracy either.  If you could do only two orders of magnitude worse than humans with special parachutes, you'd have meter class accuracy, which would be plenty good enough to hit a ship/barge/raft.

In 1958, using parachutes certainly not optimized for accuracy,  parachutists were achieving 4 meter accuracy (http://www.parachutehistory.com/men/sanbornl.html).  Surely with modern parachute technology, we can do at least as well...
Title: Re: Fairing reuse
Post by: dwheeler on 03/21/2017 06:06 pm
Another one to suggest and instantly dismiss:
Steerable foil landing on a moving platform (the idea being that the moving platform, e.g. a ship with a cushion on its aft deck, or towing an inflatable raft) can compensate somewhat for the inaccuracy of the incoming fairing.
Having seen an episode of Top Gear where they tried landing a parachutist in the back of a moving car, it seems that moving the landing target only makes things much harder...

Yeah, if the blokes at Top Gear found it difficult I'm sure the hardware/software/aero engineers at SpaceX wouldn't stand a chance...  ::) :P
Title: Re: Fairing reuse
Post by: RoboGoofers on 03/21/2017 06:57 pm
The catch idea seems a bit crazy to me because if you could catch a fairing, why not a second stage?
Title: Re: Fairing reuse
Post by: Comga on 03/21/2017 07:09 pm
The catch idea seems a bit crazy to me because if you could catch a fairing, why not a second stage?
If you have to ask, you need to do more research
The fairings don't re-enter from orbital speed, come in not too far from the launch site, have low ballistic coefficients and terminal velocity, have much lower mass, and detract from payload at well below the 1:1 ratio of the second stage.
Title: Re: Fairing reuse
Post by: Kaputnik on 03/21/2017 07:24 pm
I don't think we can extrapolate directly from a human parachutist to a fairing descending under a foil.

The human has three distinct advantages: great control authority (big control actuators, aka arms), extremely good undercarriage with long travel (aka legs), and much higher density (this varies from human to human, of course).

So a human can come in at a relatively higher speed, without being blown around by the wind, and make a fairly forceful impact whilst remaining intact.

Gut feeling is that a fairing half is not the sturdiest of things, when it comes to sudden impact loads. But anybody with insight into this please chip in.
Title: Re: Fairing reuse
Post by: RoboGoofers on 03/21/2017 07:53 pm
The catch idea seems a bit crazy to me because if you could catch a fairing, why not a second stage?
If you have to ask, you need to do more research
The fairings don't re-enter from orbital speed, come in not too far from the launch site, have low ballistic coefficients and terminal velocity, have much lower mass, and detract from payload at well below the 1:1 ratio of the second stage.

yeah I'm just hand-waving away all of that. I'm only talking about the difficulty of the catch and the effects on the aircraft. After all, catching something as large as a fairing hasn't been done before, either.

Then again ULA plans to air-catch their Vulcan engines. ::)

(Edited for clarity)

another edit:
At the end of this video they say "it's conceivable that this technique can be scaled up to payloads up to 22,000 lbs" so maybe catching the fairing isn't that crazy, though the logistics are still hard.
https://www.youtube.com/watch?v=3cnr3pX4tyw
Title: Re: Fairing reuse
Post by: Comga on 03/21/2017 08:03 pm
The catch idea seems a bit crazy to me because if you could catch a fairing, why not a second stage?
If you have to ask, you need to do more research
The fairings don't re-enter from orbital speed, come in not too far from the launch site, have low ballistic coefficients and terminal velocity, have much lower mass, and detract from payload at well below the 1:1 ratio of the second stage.

yeah just hand-waving away all of that. After all, catching something as large as a fairing hasn't been done before, either.
Then again ULA plans to air-catch their Vulcan engines. ::)

It is not clear who you are accusing of "hand waving".
Vulcan engine recovery will also be from speeds well below orbital, plan on using a massive heat shield, and are again part of the first stage, not the second.  (Fairings come off around staging, so their trajectories and mass impacts are very much like first stage elements.)  And it's still a decade out on ULA's plan.
Title: Re: Fairing reuse
Post by: manoweb on 03/21/2017 08:32 pm
Do you think ULA was serious when they said they will catch the engines? Was it not only because at the time, SpaceX announced something crazy about landing a stage, and they felt compelled to say something as crazy? Sorry I do not follow the ULA forum so maybe I do not have new info on the subject.
Title: Re: Fairing reuse
Post by: Comga on 03/21/2017 09:57 pm
Do you think ULA was serious when they said they will catch the engines? Was it not only because at the time, SpaceX announced something crazy about landing a stage, and they felt compelled to say something as crazy? Sorry I do not follow the ULA forum so maybe I do not have new info on the subject.

Many years ago, before SpaceX landed any rockets, "our own" Jonathan Goff posted about recovering the RD-180 engines of an Atlas-V using helicopter caught parafoils.  ULA has studied this.  It's not impossible.  If they need to address the issue that they are developing a new expendable rocket while a competitor is perfecting reusability, they throw up that slide.  How serious they are is hard to know.
Title: Re: Fairing reuse
Post by: TrevorMonty on 03/21/2017 10:11 pm
The catch idea seems a bit crazy to me because if you could catch a fairing, why not a second stage?
If you have to ask, you need to do more research
The fairings don't re-enter from orbital speed, come in not too far from the launch site, have low ballistic coefficients and terminal velocity, have much lower mass, and detract from payload at well below the 1:1 ratio of the second stage.

yeah just hand-waving away all of that. After all, catching something as large as a fairing hasn't been done before, either.
Then again ULA plans to air-catch their Vulcan engines. ::)

It is not clear who you are accusing of "hand waving".
Vulcan engine recovery will also be from speeds well below orbital, plan on using a massive heat shield, and are again part of the first stage, not the second.  (Fairings come off around staging, so their trajectories and mass impacts are very much like first stage elements.)  And it's still a decade out on ULA's plan.
The SMART system could be applied to 2nd stage or its engines, as HIAD is design for orbital reentry speeds.
At one stage NASA considered testing HIAD using Cygnus.
Title: Re: Fairing reuse
Post by: meekGee on 03/22/2017 01:13 am
We're *drifting* off topic.

Sorry, had to say it.

But yeah, the difficult part in second stage recovery is not snagging it, since it actually can occur closer to home base than the fairings can.  The problem is whether the weight penalty of the heat shield and maybe structural reinforcement is worth it.

Title: Re: Fairing reuse
Post by: darkenfast on 03/22/2017 02:52 am
Okay, I KNOW they said they don't want to get it wet, but I can't help but notice that the fairing halves are most of the way to being a boat.  Seal up any openings and perhaps an inflatable "bulkhead" at the back (bottom, when on the rocket) and a parachute.  The insides of the fairing are probably what they don't want to get a lot of salt-water on.  If the paint (or SPAM, or whatever coats the outside) is tolerant, the halves will just float until pick-up.  I wouldn't tow them, I would crane them into a cradle.

But...they said they wouldn't want to get them wet.  I imagine they have something else planned.  Oh, well.
Title: Re: Fairing reuse
Post by: manoweb on 03/22/2017 04:58 am
darkenfast, yes I was also surprised by that declaration. What I mean is: composites should have a pretty good resistance to saltwater, the fairing is not made out of mild steel; we are also talking about few hours max, not years floating in the sea. If recoveries become the norm they can always invest in better paint, sealing etc.
Title: Re: Fairing reuse
Post by: meekGee on 03/22/2017 07:03 am
darkenfast, yes I was also surprised by that declaration. What I mean is: composites should have a pretty good resistance to saltwater, the fairing is not made out of mild steel; we are also talking about few hours max, not years floating in the sea. If recoveries become the norm they can always invest in better paint, sealing etc.
Maybe the problem is bouncing around unpredictably on the waves?
Title: Re: Fairing reuse
Post by: darkenfast on 03/22/2017 08:09 am
darkenfast, yes I was also surprised by that declaration. What I mean is: composites should have a pretty good resistance to saltwater, the fairing is not made out of mild steel; we are also talking about few hours max, not years floating in the sea. If recoveries become the norm they can always invest in better paint, sealing etc.
Maybe the problem is bouncing around unpredictably on the waves?
Obviously, in rough weather, some water is going to get in.  As hulls go, this is a very buoyant potential boat.  In the kind of waves and swells that you get out in deep water, I believe it would just ride over everything, responding very quickly.  It would probably roll a lot because of its circular cross section.  Something called a "flopper-stopper" might help (it hangs over the side, like a sea anchor, but straight down - the drag slows the roll).  The chute(s) would make something of a sea-anchor, unfortunately if it didn't collapse, it would be like chasing a light dinghy flying a spinnaker!  Jettison capability might be good. 

Having said all that, it will be interesting to see what they REALLY have planned.
Title: Re: Fairing reuse
Post by: AncientU on 03/22/2017 10:27 pm
darkenfast, yes I was also surprised by that declaration. What I mean is: composites should have a pretty good resistance to saltwater, the fairing is not made out of mild steel; we are also talking about few hours max, not years floating in the sea. If recoveries become the norm they can always invest in better paint, sealing etc.

The fairing uses honeycomb aluminum and carbon composites as I recall.
Question: Are the void areas in the honeycomb filled and/or vented*? 

Doesn't seem like a good idea to have them air-filled and working to de-laminate the structure when under vacuum (zero pressure) externally.  But if vented, they could fill with sea water if landed in the pond which would destroy the fairing or at least make it unfit for reuse.

*All of the vacuum components we build are provided a means to vent each of the void areas to ensure no gas is trapped after vacuum is drawn.
Title: Re: Fairing reuse
Post by: iamlucky13 on 03/23/2017 09:24 pm
Oh great, inflight refueling...

This is looking more and more like a bad idea.

Most of the combat SAR helos of the USAF are already equipped with the inflight refueling kit. They need it for extended operational radius and/or time on station.

They have unlimited cash, and own the refueling tankers...and they ain't cheap.

And they're able to keep up with a C-130 because they're not towing a giant air brake.


How in the world is precision touchdown on ship/barge/raft unworkable?

Airborne Systems Dragonfly precision drop system, good for 10,000 lbs, only specs a 250m accuracy.

http://airborne-sys.com/wp-content/uploads/2016/08/ASG-DragonFly-20170206-English.pdf

Is that because 250m is the best theoretically achievable with current technology, or because there has been minimal incentive so far to improve the system to better than 250m accuracy?

It has not been demonstrated as workable, but that is different from being known to be unworkable.

darkenfast, yes I was also surprised by that declaration. What I mean is: composites should have a pretty good resistance to saltwater, the fairing is not made out of mild steel; we are also talking about few hours max, not years floating in the sea. If recoveries become the norm they can always invest in better paint, sealing etc.

The composites are probably not their concern. The fairing is more than just a shell. There are mechanical systems inside it like pushers and latch actuators that are potentially susceptible to both corrosion and salt fouling.
Title: Re: Fairing reuse
Post by: Robotbeat on 03/23/2017 10:29 pm
You can get GPS-guided parafoil payload systems that, with tweaking, can reliably hit the barge deck of an ASDS (50m x 90m). So maybe put a huge net on 4 poles (one on each corner of an ASDS) 15m high.
Title: Re: Fairing reuse
Post by: virnin on 03/23/2017 10:36 pm
You can get GPS-guided parafoil payload systems that, with tweaking, can reliably hit the barge deck of an ASDS (50m x 90m). So maybe put a huge net on 4 poles (one on each corner of an ASDS) 15m high.

That leads to the, unanswerable by us, question of how many fairings would they have to recover to pay for at least two, but more likely four, additional ASDS?
Title: Re: Fairing reuse
Post by: Robotbeat on 03/23/2017 10:38 pm
Could be a smaller and simpler vessel than an ASDS, but here's a shot:
Title: Re: Fairing reuse
Post by: nacnud on 03/23/2017 10:39 pm
I still like the scaneagle method of capture. Rather that thinking of landing these think of flying them through a volume of space within which they can be captured.
Title: Re: Fairing reuse
Post by: LouScheffer on 03/23/2017 10:58 pm

Is that because 250m is the best theoretically achievable with current technology, or because there has been minimal incentive so far to improve the system to better than 250m accuracy?

250m is definitely not a theoretical limit.    Human in the loop systems  (https://arc.aiaa.org/doi/abs/10.2514/6.2015-0075) have hit 17m (50% of the time), 42m 90% of the time.   Automated systems (http://www.staratechnologies.com/mosquito.html) have hit 30 m (50%).
Title: Re: Fairing reuse
Post by: Jet Black on 03/24/2017 08:13 am
You can get GPS-guided parafoil payload systems that, with tweaking, can reliably hit the barge deck of an ASDS (50m x 90m). So maybe put a huge net on 4 poles (one on each corner of an ASDS) 15m high.

That leads to the, unanswerable by us, question of how many fairings would they have to recover to pay for at least two, but more likely four, additional ASDS?

It's not the cost of the farings themselves, but whether they provide a bottleneck in launches. Even if they only cost $100 each, if they can't make them fast enough to keep up with their launch cadence, it would still be worth investing $100,000 per launch to catch them, because it would mean that they would be able to launch more rockets, earning millions of dollars each time.
Title: Re: Fairing reuse
Post by: guckyfan on 03/24/2017 08:38 am
You can get GPS-guided parafoil payload systems that, with tweaking, can reliably hit the barge deck of an ASDS (50m x 90m). So maybe put a huge net on 4 poles (one on each corner of an ASDS) 15m high.

That leads to the, unanswerable by us, question of how many fairings would they have to recover to pay for at least two, but more likely four, additional ASDS?

They would be a lot simpler than the Falcon ASDS. Also unlike a Falcon core it is perfectly feasible to transfer fairing halves to a ship for transport and leave the ASDS at position for a while. So just 2.
Title: Re: Fairing reuse
Post by: Basto on 03/24/2017 01:38 pm
Could be a smaller and simpler vessel than an ASDS, but here's a shot:

Another thought... aren't there two support ships that tow the barge out?  What I you had a net suspended between these two ships...
Title: Re: Fairing reuse
Post by: rsdavis9 on 03/24/2017 01:41 pm
Barges with inflatable bouncy houses.  :)
Basically like the inflatable domes that are currently available for sports events.
Inflate before landing. Allow quick deflation when fairing lands.

EDIT:
So how cheap can the barges be?
Do they need the four hydraulic props?
Could they just be actively towed? In other words 1 mph headway. Should be little or no risk to towing ship.

Title: Re: Fairing reuse
Post by: bstrong on 03/24/2017 01:56 pm
Could be a smaller and simpler vessel than an ASDS, but here's a shot:

I like this a lot. Angle the support poles outwards, and you can make do with a much smaller barge (or have a much larger net). Add the ability to quickly roll out a second net a couple of meters above the first and you can make do with one barge instead of two.
Title: Re: Fairing reuse
Post by: cscott on 03/24/2017 02:37 pm
Elon tweeted something interesting, maybe a hint at a fairing recovery experiment?
https://twitter.com/elonmusk/status/845290713776451584
Title: Re: Fairing reuse
Post by: Toast on 03/24/2017 03:15 pm
Elon tweeted something interesting, maybe a hint at a fairing recovery experiment?
https://twitter.com/elonmusk/status/845290713776451584

I don't think that has anything to do with fairing recovery, he's referring to it being the first reuse of a Falcon 9 first stage.
Title: Re: Fairing reuse
Post by: intrepidpursuit on 03/24/2017 07:10 pm
Elon tweeted something interesting, maybe a hint at a fairing recovery experiment?
https://twitter.com/elonmusk/status/845290713776451584

I don't think that has anything to do with fairing recovery, he's referring to it being the first reuse of a Falcon 9 first stage.

Referring to fate seems to indicate something experimental. He wouldn't refer to a successful launch as requiring fate, and landings have become pretty routine as well. He could just be trying to avoid over confidence, but to me that indicates something more. I think only nerds would care about the roomba, but seeing parafoils pop out of a fairing would be pretty exciting.
Title: Re: Fairing reuse
Post by: virnin on 03/24/2017 07:31 pm
You can get GPS-guided parafoil payload systems that, with tweaking, can reliably hit the barge deck of an ASDS (50m x 90m). So maybe put a huge net on 4 poles (one on each corner of an ASDS) 15m high.

That leads to the, unanswerable by us, question of how many fairings would they have to recover to pay for at least two, but more likely four, additional ASDS?

They would be a lot simpler than the Falcon ASDS. Also unlike a Falcon core it is perfectly feasible to transfer fairing halves to a ship for transport and leave the ASDS at position for a while. So just 2.

Two on each coast, so four.  Maybe 6 after Boca Chica comes online.

Agreed simpler than ASDS.  Just has to be big enough to hold the net stable during off-center catches.
Could even be manned, with crew under protective cover during catch ops.  Like a retired container ship.
Title: Re: Fairing reuse
Post by: Toast on 03/24/2017 07:39 pm
Referring to fate seems to indicate something experimental.

Relaunch of a first stage is experimental.


Title: Re: Fairing reuse
Post by: iamlucky13 on 03/24/2017 07:45 pm

Referring to fate seems to indicate something experimental. He wouldn't refer to a successful launch as requiring fate, and landings have become pretty routine as well. He could just be trying to avoid over confidence, but to me that indicates something more. I think only nerds would care about the roomba, but seeing parafoils pop out of a fairing would be pretty exciting.

Reflying a booster is experimental, and it's a significant part of SpaceX's business plan. I see nothing inconsistent with talking about fate for such a significant milestone.

Fate has bitten him twice in as many years on brand new hardware on missions thought to be routine. Although he has talked up his confidence in the past about reflight, even going as far as talking about "flight proven" hardware and booking a paying customer for the launch, I don't for one second believe he is completely free from doubts.
Title: Re: Fairing reuse
Post by: Robotbeat on 03/25/2017 12:14 am
Referring to fate seems to indicate something experimental.

Relaunch of a first stage is experimental.
It's almost like you and iamlucky13 have no idea of who Musk is. When Musk is given an opportunity to double down, he does. No way he's just a referring to reflying a stage.
Title: Re: Fairing reuse
Post by: meekGee on 03/25/2017 12:18 am
My vote is for the fact it's a re-launch.

Confident as he may be, you gotta get butterflies before this launch.  Are you kidding?

Title: Re: Fairing reuse
Post by: Toast on 03/25/2017 12:26 am
Referring to fate seems to indicate something experimental.

Relaunch of a first stage is experimental.
It's almost like you and iamlucky13 have no idea of who Musk is. When Musk is given an opportunity to double down, he does. No way he's just a referring to reflying a stage.

I won't go so far as to rule out SpaceX trying something else new on this flight (after all, they're almost always trying something new, even if we don't see it), I just think Elon referring to first stage reuse is a much more likely interpretation of this tweet. Every time Elon tweets, people bend over backwards trying to interpret his tweets (and almost always trying to make them fit their personal desires), and I think people lose sight of the fact that he probably only spends less than a minute on each tweet and most likely isn't really deliberating on his word choice. In fact, I know he spent less than a minute on this tweet, because he sent out another tweet about the Model 3 less than a minute before sending out this one (plus ~50 more in the same hour).
Title: Re: Fairing reuse
Post by: Robotbeat on 03/25/2017 01:30 am
Referring to fate seems to indicate something experimental.

Relaunch of a first stage is experimental.
It's almost like you and iamlucky13 have no idea of who Musk is. When Musk is given an opportunity to double down, he does. No way he's just a referring to reflying a stage.

I won't go so far as to rule out SpaceX trying something else new on this flight (after all, they're almost always trying something new, even if we don't see it), I just think Elon referring to first stage reuse is a much more likely interpretation of this tweet. Every time Elon tweets, people bend over backwards trying to interpret his tweets (and almost always trying to make them fit their personal desires), and I think people lose sight of the fact that he probably only spends less than a minute on each tweet and most likely isn't really deliberating on his word choice. In fact, I know he spent less than a minute on this tweet, because he sent out another tweet about the Model 3 less than a minute before sending out this one (plus ~50 more in the same hour).

You've got a good point in people over-interpreting Musk tweets. But, since we're doing it anyway: Musk often writes up drafts of tweets before he sends them. And just because it doesn't take long to say something doesn't mean he wasn't thinking about such things for a long time.

Look, everyone already knows about the fact that SES10 is a recovered booster. There's zero surprise, there, and while the reusability-can't-work goal-post-movers might have at one point said "but they just /recovered/ a rocket, they haven't actually launched it again," I really don't think this is terribly amazing (it is expected), at least not worth Musk noting what is already obvious (that SES10 will be a reused core) as if it's something unexpected.

For context, this is the actual exchange:
Quote
BlueBowles:
@elonmusk how excited are you about the SES launch next week?! I don't know how you're focused on model 3 with that ahead! #makinghistory
Quote
Elon Musk‏:
@BlueBowles If fate is on our side, it will be amazing. Will talk about that in detail next week.

What is there to discuss in detail?
Title: Re: Fairing reuse
Post by: dglow on 03/25/2017 01:39 am
What is there to discuss in detail?

The Roomba. It'll be a 'cool new surprise' for the public and nice embodiment of their efficiency and reuse ambitions.
Title: Re: Fairing reuse
Post by: Robotbeat on 03/25/2017 01:44 am
What is there to discuss in detail?

The Roomba. It'll be a 'cool new surprise' for the public and nice embodiment of their efficiency and reuse ambitions.
That's my point. It's something extra like Optimus Prime, fairing recovery, or something else like that. If Musk is discussing such stuff in detail, I doubt he'd ignore Optimus Prime, even if it weren't (for whatever reason) ready for this flight.

(But I think they're trying very hard to get it to work for this flight. That's why there are work lights around it. People are working late on this.
Title: Re: Fairing reuse
Post by: georgegassaway on 03/25/2017 06:00 am
BTW - what is the estimated mass of each  fairing half?

Given the potential changes in wind velocity at sea, I'm not so sure that a big net over a station-keeping barge (thrusters in four corners) would allow for enough of a margin for error. Also very hard to justify the cost of outfitting two barges for that, even at less cost than an ASDS landing barge.

A BIG net between two ships? They can't station keep, they'd have to be moving thru the water at some minimal speed to try to be parallel, as Navy ships have to do in refueling or taking on other supplies side-by-side from a resupply ship. That is an idea that certainly has simplicity (?) going for it (Well, relative to some other ideas), but does not seem very practical. Indeed with the mass of the fairings laid into such a big net, then the net would want to sag and pull the ships towards each other. So one ship would have to steer away from parallel to keep net taut, and may need to do so in very rough seas. That seems like a lot of precise steering to expect of a sea vessel not designed for precise maneuvering. Plus how to get the fairings out of the big big net onto the deck of a ship without a swell allowing the net to go slack and let the fairings dip into the sea water even once, negating the whole reason for a dry landing.

They would be a lot simpler than the Falcon ASDS. Also unlike a Falcon core it is perfectly feasible to transfer fairing halves to a ship for transport and leave the ASDS at position for a while. So just 2.

My thoughts, ONE barge, with aviation fuel storage onboard.  Two helicopters, each to air-snag one fairing coming down on gliding parafoil as shown in a previous post. The helicopter lowers the fairing half onto the deck and lands at one end. The other copter lowers the other fairing half and lands at the other end. Copters get refueled (if necessary, especially if they flew directly from on shore shortly before launch) and then fly back to shore alone, the fairings stay on the barge which is towed back to port.

It may not end up that way, but that seems feasible given that SpaceX does not want them to land in the ocean.

I just do not think it is very practical to air-snag the fairings then fly them back to shore under the copter. The fairings would have a lot of air drag and relatively light for their area, and would need to be flown back at a relatively low speed such as perhaps 30 knots (or perhaps less). That is a long time to be flying back from 200 or more miles out without any practical way to refuel (the idea of doing air to air refueling behind a C-130 while towing one of those ..... no way in Hades.  And AFAIK there are no civilian/commercial refueling capabilities. Only the military has such assets, which would be extremely unlikely to be used for a commercial venture such as this).

However, a lot of the mission-to-mission expense of using typical helicopters could be greatly reduced, if SpaceX developed something almost revolutionary. Because they don't have to truly design anything new, mostly scale up and build to their needs. There are big electric powered multicopters that can carry people. Scale that up a bit more, to develop a multicopter capable of carrying the mass of a payload fairing, and the automation (perhaps with remote human assist) to track down, approach, and air-snag the parachute. Then the rest could be totally automated like a hobby-type multicopter doing an automatic return to home.

I'm not counting on that actually happening. Not likely, but possible.

 Probably sounds too far-fetched right now. But then so did the idea of them doing a "Roomba" 6 months ago, or a rocket powered landing of a Falcon-9 on a barge 7 years ago. Certainly it would cost more to develop and build these than it would cost to use manned helicopters for the first few missions. But if they worked, over time they'd be far more cost effective and earn their keep. And in case of disaster, no risk to human pilots and the more expensive helicopters they fly.

The plus side of it is that making a full sized prototype of such a multicopter  would not require a long time.  Electric motor characteristics , LiPo batteries, and propellers are a known quantity so that choosing the right combo for a scaling up, for the desired payload capability, would not be too hard.  The level of automation would be the bigger issue to work out and that could be tested out and perfected in smaller scale. 

I wonder where in  the Musk-Verse that they might find anyone who knows about how to make a vehicle know exactly where it is and how to self-navigate? As well as to visually recognize certain shapes (like a parafoil canopy), and exactly how close it is to such a "target shape" in 3 dimensions, and guide itself along the correct path to intercept from behind?  :)   And at that, real-time remote human assistance might also be worth including in case the automation might be too difficult to handle every aspect of it reliably enough.

Whatever they do, or may have already tested on a flight, if they do get it to work, it'll be really great to see whatever method and techniques they use for safely landing fairings without getting wet.

Of course they may have something else up their sleeves that's not been considered much in this thread......   :)

(Yeah, I went shopping for this unreal photo, and not seriously suggesting it)
Title: Re: Fairing reuse
Post by: Kaputnik on 03/25/2017 10:56 am
Each fairing half is estimated at about a tonne (see further back in this thread).

An in house developed drone would hbe a very Musky way of tackling this. But it would be a pretty big project in its own right. Would an upsized quad opter have the speed and manoeuvrability for the task?
Title: Re: Fairing reuse
Post by: rsdavis9 on 03/25/2017 11:38 am
barge landing on air bag.
https://www.youtube.com/watch?v=3KwyftaLT-k
Title: Re: Fairing reuse
Post by: meekGee on 03/25/2017 02:49 pm
Each fairing half is estimated at about a tonne (see further back in this thread).

An in house developed drone would hbe a very Musky way of tackling this. But it would be a pretty big project in its own right. Would an upsized quad opter have the speed and manoeuvrability for the task?
Quadcopters as a form factor are much less efficient than helicopters when it comes to flying range, and automated helicopters exist.

But yes - the idea of a drone is very Musky.
Title: Re: Fairing reuse
Post by: douglas100 on 03/25/2017 04:38 pm
If you've got a vessel downrange, then the range of the helicopters or drones is less of an issue. They would be fueled or recharged on the ship or barge. They would only take off only after the rocket had left the pad. Essentially you'd be doing SMART twice, in short order. The cost of operating a second downrange vessel is an important consideration, of course.
Title: Re: Fairing reuse
Post by: Robotbeat on 03/25/2017 05:16 pm
A Megawatt peak should be more than sufficient to carry a fairing halve with a multicopter video. A battery similar to what's in a Tesla.

Scales better electrically with more motors than simply bigger motors. So 60 motors, maybe?

Anyway, I doubt they'll pursue a custom flying fairing catcher, but it's fun to speculate.
Title: Re: Fairing reuse
Post by: georgegassaway on 03/25/2017 06:40 pm
Multicopters can fly pretty fast, and are very maneuverable (check out video of “Drone racing”.  I do not know what the record speed is, but some can fly over 100 mph).  And while they can be very maneuverable, they can also do very precise smooth maneuvering as well.

If there were some big custom multicopters used for air-snagging the parachute of a descending fairing half, I would expect that the single recovery barge (or ship with a very big deck) would be located at the sweet spot of where the fairings would likely splash down from their ballistic descent if they didn’t have chutes (not accounting for local wind variation). So, the multicopters would not have to travel too far horizontally, mainly climb to altitude, and then begin to home in on its assigned fairing/parachute.  Also, being designed to have the thrust to fly back with 1 ton underneath, it would be able to ascend crazy-fast without a payload (as well as fly very fast horizontally to catch-up to rendezvous for the air-snag maneuver).  After the snag,  not needing to fly very fast horizontally (mostly the issue of the drag and wobbling of fairing underneath while traveling horizontally). And ideally the whole thing would happen mostly directly above the barge (also thanks in part to the steerable parachute), so if the air-snag was say a mile up, it may have less than a mile to fly horizontally. 

This video (link below) by Casey Neistat gives info on the multicopter that was used for the Christmas video that he made.  16 motors, 16 props…..  a “HexaDecaCopter” (Hmm, with 8 x 2 layout I'd say more like a OctoCopter 2X, though I do get that hex + deca implies the number 16. An 8-armed multicopter  is called an OctoCopter).   By itself, it weighs 165 pounds. With Neistat, all the rigging, snowboard, total flying weight of about 365 pounds.  Max thrust of 1050 pounds. That info comes from this video he made about it:

https://www.youtube.com/watch?v=DyUrqZBs2XA&t=2s

It was made by three people, (two of whom are husband and wife) over a period of about a year. It is not known if they did this full-time as their one and only project, or a side project.  It is described as “home made”. So I suspect it was done as a side project. I suspect that if they were a small “mom and pop and friend” company that had the $ and time to do nothing else but this, they could have done it in far less time. Just as a hobbyist I may have a project that takes me 6 months to get done…. but that does not mean I put in 40 hours a week on it for 6 months, it’s a side project.  I do wish I knew more about them. Whoever they are, he trusted his life to them. For anyone who does not watch the whole thing, for the flying scenes he wore a harness with a cable running up one arm, hooked to the copter,  not just holding on by one hand.

One company that has made a “sit inside” passenger Multicopter prototype is Volocopter:

http://volocopter.com/index.php/en/

No CGI  and no photoshop stuff here,  their prototype really does exist and flies (youtube videos). I’m not suggesting that SpaceX would buy two of these and modify them, as for one they are probably not big enough to have enough thrust to handle a fairing half. But as an example of a yet larger configuration that actually does exist. It has 18 motors & props (thrust could be nearly doubled if it also had a lower set of motors/props  under the upper ones as the one Niestat used has, at a cost of about half the duration for the same battery. Still probably not quite enough thrust). So this generic multicopter scale-up of a scale-up could be….. scaled-up.  And we know SpaceX ain’t afraid of flying vehicles that have dozens of clustered motors…… :)

So, I do not expect they will do this. But it has potential. I do think that such a  one ton cargo carrying multicopter will exist someday.  Just a matter of how soon some company (or military branch) can justify doing it and make it happen.
Title: Re: Fairing reuse
Post by: bstrong on 03/25/2017 06:47 pm
And don't forget that Elon's buddy Larry Page has not one, but two separate VTOL electric aircraft companies.

https://electrek.co/2016/10/25/first-picture-of-what-is-believed-to-be-larry-pages-electric-vtol-aircraft/
Title: Re: Fairing reuse
Post by: Lar on 03/26/2017 11:05 am
Referring to fate seems to indicate something experimental.

Relaunch of a first stage is experimental.
It's almost like you and iamlucky13 have no idea of who Musk is. When Musk is given an opportunity to double down, he does. No way he's just a referring to reflying a stage.

His ENTIRE CAREER has been one big giant parlay. So far he's been winning (and we all benefit).  That's off topic but I wanted to throw it out there. Because, ya, to Elon, this reuse is already routine, IMHO.

I don't think the "fate" comment applies to fairing reuse, unless we fanspies really blew it, as there isn't any gear on the "fairing" ship to speak of yet. I think it's the Xoomba, but we'll find out soon enough.
Title: Re: Fairing reuse
Post by: intrepidpursuit on 03/26/2017 02:22 pm
My original post implied that stage reuse was not experimental. They can't consider it very experimental since they have a paying customer's payload on top. No, Elon has something else planned, and I don't think the roomba is exciting enough to be it.
Title: Re: Fairing reuse
Post by: Robotbeat on 03/26/2017 02:35 pm
My original post implied that stage reuse was not experimental. They can't consider it very experimental since they have a paying customer's payload on top. No, Elon has something else planned, and I don't think the roomba is exciting enough to be it.
The Roomba is pretty dang exciting, because Musk probably wants to use it or things like it to do more crazy things. And they need to do similar crazy things on Mars.

Smart money is on the Roomba. Optimus Prime.
Title: Re: Fairing reuse
Post by: LouScheffer on 03/26/2017 02:56 pm
Considering the technical problem only, and not cost, it seems like this is entirely feasible with existing technology.

(a) Fairing deploys a parachute.  There are many that can handle such loads (2 tonnes for a fairing half?)

(b) Two helicopters, taking off from a ship, catch the parachutes.  There are plenty of helicopters (not even the largest ones) that can handle this load (say Mi-8/Mi-17).  Range is not a problem since the ship is close to where the fairing comes down.

(c) The helicopters lower the fairings onto large airbags on the deck of a ship.  An internet search shows 15x15m airbags are stock items.  This should be gentle enough to not damage the fairing, and it never gets wet.

So now we have a working scheme, so the problem is to reduce the cost.  Perhaps they could put the airbags on the ASDS, and bring the fairings back with the booster.   Perhaps the helicopters can go out on the ASDS, take off before the booster lands, catch the fairings, then return to land unladen (the ferry range would indicate this might be possible.  Bahamas are about 400 km from landing zone.  Ferry range is close to 1000 km.   So the helicopter could use half its fuel making the catch, and still have enough to get to shore.).

Anyway, at an estimated cost of $3M per fairing, costs could be quite high and still worthwhile.

EDIT:  Added range to Bahamas, and ferry range.
Title: Re: Fairing reuse
Post by: Lar on 03/26/2017 09:41 pm
Sorry for being diversionary but let's stick to fairing reuse here, not what the big surprise is. Mea culpa.
Title: Re: Fairing reuse
Post by: Johnnyhinbos on 03/26/2017 09:54 pm
Humm - I'm going to be on a research vessel off Bimini, departing Miami April 3. I'll have to keep an eye out...
Title: Re: Fairing reuse
Post by: Robotbeat on 03/27/2017 12:21 am
A K-max helicopter should be capable of capturing the fairing half. It's $5m, plus operations. But they're relatively affordable to operate. If based from an ASDS, they wouldn't need to fly much.

But I think SpaceX could build their own, short-range electric drone capable of capturing a fairing half for about $1 million.
Title: Re: Fairing reuse
Post by: Jet Black on 03/27/2017 11:28 am
Referring to fate seems to indicate something experimental.

iirc this next launch is pretty far out on the edge of the envelope for a successful landing - where I include the rocket still being useable in successful.
Title: Re: Fairing reuse
Post by: CraigLieb on 03/27/2017 03:10 pm
We are beginning to see the designs of Elon, the evil genius...  (pinkie firmly planted in corner of mouth)

The fairing will deploy cold-gas thrusters and small pop-out grid fins to stabilize into a flyable aeroshell, navigating to a selected capture zone. At which point, the very large airship will open up it's large under slung cargo hold and the fairings will fly in and be caught in nets. The airship will then make its way to Elon's secret volcano lair ... which opens up it's hidden landing pad area, etc. Submarines or fast boats will return the shells to shore for additional processing.

 8)

 
Title: Re: Fairing reuse
Post by: oiorionsbelt on 03/27/2017 07:39 pm
A K-max helicopter should be capable of capturing the fairing half. It's $5m, plus operations. But they're relatively affordable to operate. If based from an ASDS, they wouldn't need to fly much.

But I think SpaceX could build their own, short-range electric drone capable of capturing a fairing half for about $1 million.
Or the fairing half is the drone.
Title: Re: Fairing reuse
Post by: georgegassaway on 03/27/2017 10:03 pm
Or the fairing half is the drone.

I actually considered that idea.  But the added mass of the motors, props, various other hardware (including deployment mechanisms), and especially the batteries, would likely be so much that it would impact either the payload mass to orbit or reduce the orbit for the same payload mass. That presumes not short-changing the core's fuel to land itself, by burning a bit longer to make up for the performance hit of heavier shrouds.

Of course, adding a steerable chute also adds SOME mass too. Gut feeling is that it would be way less extra mass than a "Transformer" Shroud-Drone, but must admit I don't have a good mass estimate for what it would take.
Title: Re: Fairing reuse
Post by: RobLynn on 03/27/2017 10:48 pm
A K-max helicopter should be capable of capturing the fairing half. It's $5m, plus operations. But they're relatively affordable to operate. If based from an ASDS, they wouldn't need to fly much.

But I think SpaceX could build their own, short-range electric drone capable of capturing a fairing half for about $1 million.
Or buy 6x robinson R22s or R44s for abut $2-3 million (less than a single k-max), implement autonomous control on them, and adapt the software these guys made to catch the falling fairing halves:
https://youtu.be/oDyfGM35ekc?t=67

The helicopters can use long ropes to be 100's of meters away from the falling fairings, the nets can be pretty big so less precision is required, the net impacts can be very gentle, and apart from whatever modifications are needed to successfully re-enter almost no other add-ons or controls are needed on the fairings.
Title: Re: Fairing reuse
Post by: Robotbeat on 03/28/2017 03:56 am
More complicated, tho. I think they'd prefer to roll their own drone or use autonomous (or piloted, I suppose) K-Maxes.
Title: Re: Fairing reuse
Post by: Kaputnik on 03/28/2017 06:56 am
Zero evidence for this, but splitting the fairing into four would simplify things a fair bit.
Title: Re: Fairing reuse
Post by: matthewkantar on 03/28/2017 07:24 am
Zero evidence for this, but splitting the fairing into four would simplify things a fair bit.

The washering, flanging, and hardware for the joint adds a lot of weight.
Title: Re: Fairing reuse
Post by: Kaputnik on 03/28/2017 12:07 pm
Zero evidence for this, but splitting the fairing into four would simplify things a fair bit.

The washering, flanging, and hardware for the joint adds a lot of weight.

Fair point. I can't t think of any LVs that use anything other than a two part clamshell.
Title: Re: Fairing reuse
Post by: cscott on 03/28/2017 12:11 pm
Zero evidence for this, but splitting the fairing into four would simplify things a fair bit.
What's your reasoning?

It seems to me it would just multiply the complexity: four avionics packages, four parafoils, four joints, four ASDSes, four helicopters, four airbags, etc.

In fact, some folks spent a lot of time upthread trying to figure out how to reattach the fairing halves after separation to create *one* flyback item.  That also adds a lot of complexity.

Seems like two halves is the sweet spot.  But I'm interested to hear why you think four is better.
Title: Re: Fairing reuse
Post by: Robotbeat on 03/28/2017 12:14 pm
Two halves connected by a huge hinge? 😂
Title: Re: Fairing reuse
Post by: Confusador on 03/28/2017 12:16 pm
Two halves connected by a huge hinge? 😂

That was the idea, yes, from the very first page of this thread.  I think it's been done to death at this point.

Edit for clarity: I suspect Robotbeat remembers that, and is joking. But I don't want that to accidentally encourage anyone...
Title: Re: Fairing reuse
Post by: rsdavis9 on 03/28/2017 12:44 pm
Zero evidence for this, but splitting the fairing into four would simplify things a fair bit.
What's your reasoning?

It seems to me it would just multiply the complexity: four avionics packages, four parafoils, four joints, four ASDSes, four helicopters, four airbags, etc.

In fact, some folks spent a lot of time upthread trying to figure out how to reattach the fairing halves after separation to create *one* flyback item.  That also adds a lot of complexity.

Seems like two halves is the sweet spot.  But I'm interested to hear why you think four is better.

Each piece is lighter and easier to "catch"?

I personally like barge with "fall bag" or basically large inflatable dome material.
Title: Re: Fairing reuse
Post by: Welsh Dragon on 03/28/2017 01:01 pm
Zero evidence for this, but splitting the fairing into four would simplify things a fair bit.

The washering, flanging, and hardware for the joint adds a lot of weight.

Fair point. I can't t think of any LVs that use anything other than a two part clamshell.
Pretty sure some Titans used three part fairings.
Title: Re: Fairing reuse
Post by: MP99 on 03/28/2017 06:53 pm
Two halves connected by a huge hinge? 😂

Make them flap, and you'd have an ornithopter!!  BFG.

Cheers, Martin

Title: Re: Fairing reuse
Post by: Jim on 03/28/2017 08:23 pm
Zero evidence for this, but splitting the fairing into four would simplify things a fair bit.

The washering, flanging, and hardware for the joint adds a lot of weight.

Fair point. I can't t think of any LVs that use anything other than a two part clamshell.

Titan IV, Titan III, Delta II 10 metal, Skylab
Title: Re: Fairing reuse
Post by: cscott on 03/28/2017 08:42 pm
Didn't Apollo also have a four-part fairing around the LEM?
Title: Re: Fairing reuse
Post by: nacnud on 03/28/2017 08:46 pm
Yep
Title: Re: Fairing reuse
Post by: iamlucky13 on 03/28/2017 11:28 pm
Referring to fate seems to indicate something experimental.

Relaunch of a first stage is experimental.
It's almost like you and iamlucky13 have no idea of who Musk is. When Musk is given an opportunity to double down, he does. No way he's just a referring to reflying a stage.

When has he doubled down as you suggest?

Maybe I'm confused about who Musk is, but I'm fairly certain he's proud of his businesses and can't resist talking about them. When he's got something up his sleeve, he's generally dropped clear hints he's got something up his sleeve. He wants you paying attention for the punchline, not turning off the stream once the rocket touches down, so you miss the fairing landing.

Two make two more specific comments: using a fancy peace of ground support equipment to assist with recovery after the hard part is over is not fateful.

Successfully recovering a fairing is arguably fateful, but not nearly to the same degree as proving he really can refly rocket stages. Reflying a rocket stage is significant enough there's no reason to ascribe comments about fate to anything else unless Musk acts like Musk usually does and gives you a clear reason.

I have other reasons for expecting they will probably not be recovering a fairing this launch, but I'm not able to discuss them at this time.
Title: Re: Fairing reuse
Post by: cscott on 03/29/2017 01:12 am
This will be a very hot landing, but if it comes back, SES gets "bits" for their boardroom.

The hot landing probably explains Elon's "fate" tweet from last week, then.  Maybe a three-engine landing burn again, and they've never yet only once been successful with that.

EDIT: from the launch log (http://forum.nasaspaceflight.com/index.php?topic=40544.msg1550541#msg1550541), only 4 attempts at multi-engine burns:
SES-9: 3-engine burn, unsuccessful.
JCSAT-14: 3-engine burn, successful.
Thaicom-8: 1-3-1 burn, successful. (Not a 3-engine *landing* burn AIUI.)
Eutelsat 117W: 3-engine burn, unsuccessful.

This landing is apparently "hot".  SES-9 was a 3-engine landing burn that took out OCISLY from space.  "Fate" could be simply referring to the narrow-margin landing attempt on this launch.

I hope OCISLY's clover is working!
Title: Re: Fairing reuse
Post by: Robotbeat on 03/29/2017 01:12 am
It's not fairing recovery I think he'll be talking about, but our roomba friend. My main point has always been that the thing he's referring to in the tweet is not just reuse of the first stage.
Title: Re: Fairing reuse
Post by: Semmel on 03/29/2017 06:29 am
My main point has always been that the thing he's referring to in the tweet is not just reuse of the first stage.

I am pretty sure it is first stage reuse. It's the one thing that is disruptive of the launch industry. It's the one thing the success of SpaceX will hinge on. I mean not this flight particularly but reuse in general. This flight is the first occasion where proving reuse is possible and maybe even economic. Any other technical challenge like fairing reuse will not determine SpaceXs future. But reuse must work or SpaceX has failed. That's why (in my opinion) musk is talking about fate.
Title: Re: Fairing reuse
Post by: john smith 19 on 03/29/2017 06:38 am
I associate a "hot" landing with a stage that has pushed the rest of the stack to higher velocity or altitude than usual missions.

It will therefor be coming in at a faster velocity. OTOH it had to burn harder on launch suggests it will also have tighter restrictions on how much landing propellant it can carry.

So propellant margins are tight and the terminal landing process is shorter than usual. That means this time round engines really need to start at the first attempt and burn at full planned thrust for the full duration. It's unlikely the landing legs can soak up much of the KE left if the engines do their part fully.

All of which will make for very exciting video.
Title: Re: Fairing reuse
Post by: john smith 19 on 03/29/2017 06:41 am
TBH I've never really understood need for the very rigid, heavy fairings that LV's use.

I've often wondered if you could get by with an inflatable design, soft of like those emergency half circular shelters, but with two edge to edge and both on end.
Title: Re: Fairing reuse
Post by: Kaputnik on 03/29/2017 11:36 am
TBH I've never really understood need for the very rigid, heavy fairings that LV's use.

I've often wondered if you could get by with an inflatable design, soft of like those emergency half circular shelters, but with two edge to edge and both on end.

 Seriously? For max Q, we're talking around mach 1 and airliner cruising altitude. That's a pretty tough gig. I don't see too many inflatable supersonic aircraft going about.
Title: Re: Fairing reuse
Post by: john smith 19 on 03/29/2017 01:05 pm
TBH I've never really understood need for the very rigid, heavy fairings that LV's use.

I've often wondered if you could get by with an inflatable design, soft of like those emergency half circular shelters, but with two edge to edge and both on end.

 Seriously? For max Q, we're talking around mach 1 and airliner cruising altitude. That's a pretty tough gig. I don't see too many inflatable supersonic aircraft going about.
The difference between launch and cruise.  During launch dynamic pressure is quoted in pounds per sq foot because the rise in terms of psi (IE 1/144 smaller) is pretty small. I could see the need for a rigid fairing if there is a real fear of impact damage to the outside of the payload or if the fairing has inside ties to the payload to keep in place. 

The former is a real threat but the latter is not done AFAIK, even for payloads that require "vertical launch" due to the fragility of some of their components.

A lot of common practice in this industry seems to have evolved during the development of ICBMs.

I'd also point out that Joseph Kittinger and Felix Baumgarntner have gone supersonic in free fall inside nothing but a flexible sack (or "pressure suit" as I like to call it   :)  ).

Rigid nose cones assured the aerodynamics and their weight was acceptable. But LV's don't sit in silos for decades with staff walking around them periodically for inspection that might damage their payloads by dropping tools on them. The best way to protect a payload is inside a vehicle assembly building, followed by a transfer to the pad and a launch ASAP.

The two issues I can see are the very high noise levels and maintaining a controlled environment, which means making it pressure tight to slightly above atmospheric pressure.

Very little in this industry is original so I'd love to find some NASA report from the 1960's that looked at this and explains why it's unrealistic but so far all I've found is a brief discussion from 2015.

Title: Re: Fairing reuse
Post by: Kaputnik on 03/29/2017 05:21 pm
The notion that we only see PLFs because that's what works for an ICBM seems a bit unrealistic. I'm sure the question of payload fairing mass, and how to reduce it, has been given at least *some* consideration by aerospace engineers over the last five decades.

But let's consider an inflatable fairing. It would be a pressure-stabilised structure, which we know works well on tankage. However propellant is incompressible so you can fairly pump up the tank pressure. A payload designed to operate in a vacuum would need to also be rated for the pressure of the inflated fairing (assuming a single skin structure). This pressure would be whatever max-Q is plus whatever is needed to make the PLF completely rigid and aerodynamically stable. That's got to be a fair bit of pressure...
Title: Re: Fairing reuse
Post by: Jim on 03/29/2017 05:37 pm
A lot of common practice in this industry seems to have evolved during the development of ICBMs.


Wrong, single warhead ICBM's have no need for fairings
Title: Re: Fairing reuse
Post by: Jim on 03/29/2017 05:40 pm
I could see the need for a rigid fairing if there is a real fear of impact damage to the outside of the payload or if the fairing has inside ties to the payload to keep in place. 


Neither are applicable.
Title: Re: Fairing reuse
Post by: matthewkantar on 03/29/2017 05:45 pm
Having to be rated for pressure would seem less consequential than having to be rated for rapid decompression. Fairings let the pressure drop as the rocket climbs. With an inflatable fairing, you would need to maintain the correct pressure differential until the faring is unneeded, then figure out how to get rid of it in a reliable way, not by popping it like a balloon. The valving problem seems doable if problematic. The disposal part less so.

I suppose an inflatable fairing could be an envelope that is inflated, leaving the resulting cavity at ambient pressure. It could have two halves that meet at rigid frames and separate as normal, but any weight savings start to disappear with rigid structure, hardware, and two layers of material.

Matthew

edit, fixed typo, 3.29.17 1:49 edt
Title: Re: Fairing reuse
Post by: Jim on 03/29/2017 05:46 pm

I've often wondered if you could get by with an inflatable design,

Not viable.  See elsewhere in the forum as to why.
Title: Re: Fairing reuse
Post by: whitelancer64 on 03/29/2017 06:00 pm
TBH I've never really understood need for the very rigid, heavy fairings that LV's use.

I've often wondered if you could get by with an inflatable design, soft of like those emergency half circular shelters, but with two edge to edge and both on end.

 Seriously? For max Q, we're talking around mach 1 and airliner cruising altitude. That's a pretty tough gig. I don't see too many inflatable supersonic aircraft going about.
The difference between launch and cruise.  During launch dynamic pressure is quoted in pounds per sq foot because the rise in terms of psi (IE 1/144 smaller) is pretty small. I could see the need for a rigid fairing if there is a real fear of impact damage to the outside of the payload or if the fairing has inside ties to the payload to keep in place. 

The former is a real threat but the latter is not done AFAIK, even for payloads that require "vertical launch" due to the fragility of some of their components.

A lot of common practice in this industry seems to have evolved during the development of ICBMs.

I'd also point out that Joseph Kittinger and Felix Baumgarntner have gone supersonic in free fall inside nothing but a flexible sack (or "pressure suit" as I like to call it   :)  ).

Rigid nose cones assured the aerodynamics and their weight was acceptable. But LV's don't sit in silos for decades with staff walking around them periodically for inspection that might damage their payloads by dropping tools on them. The best way to protect a payload is inside a vehicle assembly building, followed by a transfer to the pad and a launch ASAP.

The two issues I can see are the very high noise levels and maintaining a controlled environment, which means making it pressure tight to slightly above atmospheric pressure.

Very little in this industry is original so I'd love to find some NASA report from the 1960's that looked at this and explains why it's unrealistic but so far all I've found is a brief discussion from 2015.

Fairings do several things to protect the payload. They protect against environmental hazards, as well as thermal, aerodynamic, noise, and EM stresses. Environmental and thermal is very important during the sit on the pad, which could be for several days in varying weather conditions, but could also be helpful during launch, if there's flight through a cloud, or a bird strike. Aerodynamic and noise during launch - as noted, Max Q is almost always supersonic and still well within the stratosphere. If there's an airplane with inflatable leading wing edges that can go supersonic, I'd love to know about it. EM conditions can vary during launch and on the pad, but the most extreme would be a lightning strike - the EM forces must be diverted so the payload isn't harmed.

Inflatable is just not going to cut it for any of these functions.
Title: Re: Fairing reuse
Post by: SLC on 03/29/2017 11:21 pm
TBH I've never really understood need for the very rigid, heavy fairings that LV's use.

I've often wondered if you could get by with an inflatable design, soft of like those emergency half circular shelters, but with two edge to edge and both on end.

 Seriously? For max Q, we're talking around mach 1 and airliner cruising altitude. That's a pretty tough gig. I don't see too many inflatable supersonic aircraft going about.
The difference between launch and cruise.  During launch dynamic pressure is quoted in pounds per sq foot because the rise in terms of psi (IE 1/144 smaller) is pretty small. I could see the need for a rigid fairing if there is a real fear of impact damage to the outside of the payload or if the fairing has inside ties to the payload to keep in place. 

The former is a real threat but the latter is not done AFAIK, even for payloads that require "vertical launch" due to the fragility of some of their components.

A lot of common practice in this industry seems to have evolved during the development of ICBMs.

I'd also point out that Joseph Kittinger and Felix Baumgarntner have gone supersonic in free fall inside nothing but a flexible sack (or "pressure suit" as I like to call it   :)  ).

Rigid nose cones assured the aerodynamics and their weight was acceptable. But LV's don't sit in silos for decades with staff walking around them periodically for inspection that might damage their payloads by dropping tools on them. The best way to protect a payload is inside a vehicle assembly building, followed by a transfer to the pad and a launch ASAP.

The two issues I can see are the very high noise levels and maintaining a controlled environment, which means making it pressure tight to slightly above atmospheric pressure.

Very little in this industry is original so I'd love to find some NASA report from the 1960's that looked at this and explains why it's unrealistic but so far all I've found is a brief discussion from 2015.

Fairings do several things to protect the payload. They protect against environmental hazards, as well as thermal, aerodynamic, noise, and EM stresses. Environmental and thermal is very important during the sit on the pad, which could be for several days in varying weather conditions, but could also be helpful during launch, if there's flight through a cloud, or a bird strike. Aerodynamic and noise during launch - as noted, Max Q is almost always supersonic and still well within the stratosphere. If there's an airplane with inflatable leading wing edges that can go supersonic, I'd love to know about it. EM conditions can vary during launch and on the pad, but the most extreme would be a lightning strike - the EM forces must be diverted so the payload isn't harmed.

Inflatable is just not going to cut it for any of these functions.
Then again, NASA seems quite serious about HIAD inflatable heat-shields for atmospheric entry - see the two references quoted in the Wikipedia NASA HIAD paragraph here:

http://en.wikipedia.org/wiki/Atmospheric_entry#NASA_HIAD

If a re-entry heat-shield can be made inflatable, why not a fairing?
Title: Re: Fairing reuse
Post by: Jim on 03/30/2017 12:16 am

If a re-entry heat-shield can be made inflatable, why not a fairing?

It isn't a whole heat heat, it is only the parameter and it is not protecting anything in the interior.
Title: Re: Fairing reuse
Post by: Jim on 03/30/2017 12:30 am

Random max q number of 1000 psf.

typical fairing frontal area 200 sq ft.

so, what inflatable tube of 50 ft or so can support 100 tons.

Now add in a slight angle of attack which:
a.  increases the frontal area
b.  induces bending forces.
c. while still maintaining a dynamic envelope of a few inches.
Title: Re: Fairing reuse
Post by: Robotbeat on 03/30/2017 02:40 am
I think you could build an inflatable fairing if you pumped it to a high enough pressure, but why? It's dumb. Separation is actually more complicated. The payload now has to handle higher than Earth pressure. It's now a pad hazard as it could pop. It probably is worse acoustically as well.

I think you could definitely build an inflatable tube to hold 50-100 tons. But it's a terrible idea.
Title: Re: Fairing reuse
Post by: LouScheffer on 03/30/2017 04:40 am

Random max q number of 1000 psf.

typical fairing frontal area 200 sq ft.

so, what inflatable tube of 50 ft or so can support 100 tons.

Atlas balloon tank.
Title: Re: Fairing reuse
Post by: guckyfan on 03/30/2017 10:39 am
Atlas ballon tank is not inflatable.
Title: Re: Fairing reuse
Post by: Johnnyhinbos on 03/30/2017 11:02 am
Ok, I'm not jumping on the inflatable fairing bandwagon, but I do want to point out that perhaps when posters refer to an inflatable fairing they aren't referring to an outer shell that encapsulates the payload and the entire volume is pumped up to desired pressure for rigidity, but rather an inflatable fairing would be, say, two parts just like a traditional SpaceX fairing, but each half has an outer and an inner wall so that only the fairing itself is pressurized. It would still have the same bulkhead fittings for HVAC etc, the same vents to allow the payload to equalize to ambient pressure, etc.

The perceived benefits would be weight, possible cost, and possibly the halves would be easier to recover.

Boosting this hollow shell to required stiffness pressure isn't that hard, requires much less gas, and stiffness increases with height (though no doubt a pressure relief valve is required to prevent overpressure events.)

Materiel science and tech have come a long way and I'd say this concept is definitely solvable if desired.

But again, just making a point. Not stating my personal opinion.
Title: Re: Fairing reuse
Post by: Lar on 03/30/2017 11:15 am
SpaceX optimize for cost. Not PMF, not anything else. Cost.

I'm not seeing how an inflatable fairing, even if it could be made to work, makes recovery easier, or costs so much less that it can be discarded without concern like the blisterpack on your next phone charger cable[1]... Even if you could figure out how to discard (separate) cleanly.

I mean, I see paths to solving many of these problems. But no reason to do so. Rigid fairings are going to fly better once separated anyway.

1 - there are movements afoot to get rid of blisterpacks in favor of reusable packaging but you know what I mean.
Title: Re: Fairing reuse
Post by: Kaputnik on 03/30/2017 11:20 am
This inflatable fairing thing is like beating a dead horse.
Single skin: too much pressure on the payload
Double skin: you lose all the weight advantages

There must be realistic methods of reducing fairing weight. E.g. a weaker fairing connected to a load bearing pathway through the payload (trade payload mass for fairing mass). Or a single piece fairing with a higher risk jettison manoeuvre. Or reduced fairing size to cater for smaller payload, trading higher manufacturing costs and multiple configurations for slight weight loss.
Title: Re: Fairing reuse
Post by: Lar on 03/30/2017 12:03 pm
This inflatable fairing thing is like beating a dead horse.
Single skin: too much pressure on the payload
Double skin: you lose all the weight advantages

There must be realistic methods of reducing fairing weight. E.g. a weaker fairing connected to a load bearing pathway through the payload (trade payload mass for fairing mass). Or a single piece fairing with a higher risk jettison manoeuvre. Or reduced fairing size to cater for smaller payload, trading higher manufacturing costs and multiple configurations for slight weight loss.

I'm sure there are.  Let ULA pursue them. SpaceX optimizes for cost. Not weight. It so happens that a high PMF often reduces cost, but it's not the goal per se...
Title: Re: Fairing reuse
Post by: Jim on 03/30/2017 01:35 pm

Random max q number of 1000 psf.

typical fairing frontal area 200 sq ft.

so, what inflatable tube of 50 ft or so can support 100 tons.

Atlas balloon tank.

That is at 30 to 40 psi and did not separate
Title: Re: Fairing reuse
Post by: john smith 19 on 03/30/2017 02:29 pm
I'm sure there are.  Let ULA pursue them. SpaceX optimizes for cost. Not weight. It so happens that a high PMF often reduces cost, but it's not the goal per se...
That's a fair point .

Turning the question on its head how much mass does making the opening mechanism reclosable add to the current design. In fact what does a current PLF for the F9 weigh? I'm guessing several tonnes.
Title: Re: Fairing reuse
Post by: Jim on 03/30/2017 02:36 pm

There must be realistic methods of reducing fairing weight. E.g. a weaker fairing connected to a load bearing pathway through the payload (trade payload mass for fairing mass).

That isn't realistic.  Fairing mass is not a one to one ratio with payload mass.
Title: Re: Fairing reuse
Post by: meekGee on 03/30/2017 04:28 pm
This inflatable fairing thing is like beating a dead horse.
Single skin: too much pressure on the payload
Double skin: you lose all the weight advantages

There must be realistic methods of reducing fairing weight. E.g. a weaker fairing connected to a load bearing pathway through the payload (trade payload mass for fairing mass). Or a single piece fairing with a higher risk jettison manoeuvre. Or reduced fairing size to cater for smaller payload, trading higher manufacturing costs and multiple configurations for slight weight loss.
The central pillar is exactly what I was thinking for the fairings of the comsats deployers, since you already have the dispenser spine in place.

You could even take it a step further, with radial support, and remove most of the structural demand on the fairing.
Title: Re: Fairing reuse
Post by: MikeAtkinson on 03/30/2017 04:36 pm
This inflatable fairing thing is like beating a dead horse.
Single skin: too much pressure on the payload
Double skin: you lose all the weight advantages

There must be realistic methods of reducing fairing weight. E.g. a weaker fairing connected to a load bearing pathway through the payload (trade payload mass for fairing mass). Or a single piece fairing with a higher risk jettison manoeuvre. Or reduced fairing size to cater for smaller payload, trading higher manufacturing costs and multiple configurations for slight weight loss.
The central pillar is exactly what I was thinking for the fairings of the comsats deployers, since you already have the dispenser spine in place.

You could even take it a step further, with radial support, and remove most of the structural demand on the fairing.

But that central pillar would then go all the way to orbit, wouldn't it? So might not end up being a net win, even for LEO, unlikely to be a net win for GTO.
Title: Re: Fairing reuse
Post by: meekGee on 03/30/2017 04:42 pm
This inflatable fairing thing is like beating a dead horse.
Single skin: too much pressure on the payload
Double skin: you lose all the weight advantages

There must be realistic methods of reducing fairing weight. E.g. a weaker fairing connected to a load bearing pathway through the payload (trade payload mass for fairing mass). Or a single piece fairing with a higher risk jettison manoeuvre. Or reduced fairing size to cater for smaller payload, trading higher manufacturing costs and multiple configurations for slight weight loss.
The central pillar is exactly what I was thinking for the fairings of the comsats deployers, since you already have the dispenser spine in place.

You could even take it a step further, with radial support, and remove most of the structural demand on the fairing.

But that central pillar would then go all the way to orbit, wouldn't it? So might not end up being a net win, even for LEO, unlikely to be a net win for GTO.
It already does, and is already holding 10 tons of cantilevered satellites off of it, at high g.

Designing it to give support for the fairing would not add significant weight IMO, but would not only save fairing weight, but make it much easier to manufacture.

With less constraints, maybe also easier to recover and reuse.
Title: Re: Fairing reuse
Post by: Kaputnik on 03/30/2017 04:49 pm

There must be realistic methods of reducing fairing weight. E.g. a weaker fairing connected to a load bearing pathway through the payload (trade payload mass for fairing mass).

That isn't realistic.  Fairing mass is not a one to one ratio with payload mass.

I meant 'realistic compared to inflatable PLFs'. I'm not saying it's a good idea compared to what already happens.

If someone did think it was a good idea to pass fairing loads through the payload (or, more specifically, the dispenser), then you have to think of a way to reliably decouple that load for jettison, and also swallow the additional manufacturing and qualifying for a complete second PLF system (because not all payloads are going to be able to do this).
Title: Re: Fairing reuse
Post by: ChrisC on 03/30/2017 04:59 pm
Steve Jurvetson on Facebook (https://www.facebook.com/jurvetson/posts/10158475022955611) :

Quote from: Steve Jurvetson
At the historic Apollo 11 Pad 39A for the first reuse of a SpaceX booster (and first attempt at a fairing recovery). Go SpaceX and SES-10, go, go go!
Title: Re: Fairing reuse
Post by: cscott on 03/30/2017 05:06 pm
Confirmation!
Title: Re: Fairing reuse
Post by: Lar on 03/30/2017 05:11 pm
Steve Jurvetson on Facebook (https://www.facebook.com/jurvetson/posts/10158475022955611) :

Quote from: Steve Jurvetson
At the historic Apollo 11 Pad 39A for the first reuse of a SpaceX booster (and first attempt at a fairing recovery). Go SpaceX and SES-10, go, go go!

He probably has a better handle than most of us on this, since he is (from his FB page)....
- Board of Directors at SpaceX
- Board of Directors at Tesla
- Partner at DFJ

He didn't accept my friend request yet, oddly...

We've not seen a lot of signs of this being tested but maybe they did most of it out at sea. 

(just wow!)
Title: Re: Fairing reuse
Post by: Jarnis on 03/30/2017 05:23 pm
Must mean that the recovery gear doesn't weight much as this is a marginal mission for booster recovery to start with. Would've expected the next one (NROL) to be far more likely candidate due to the margins there since it is a RTLS.

Of course on SES-10 they have the SpaceX Flotilla out there already, while on a RTLS mission they would have to go out separately just for the fairing(s).
Title: Re: Fairing reuse
Post by: Toast on 03/30/2017 05:58 pm
Steve Jurvetson on Facebook (https://www.facebook.com/jurvetson/posts/10158475022955611) :

Quote from: Steve Jurvetson
At the historic Apollo 11 Pad 39A for the first reuse of a SpaceX booster (and first attempt at a fairing recovery). Go SpaceX and SES-10, go, go go!

Guess I get to eat my words then. Sounds like this will be an awesome launch!
Title: Re: Fairing reuse
Post by: Machdiamond on 03/30/2017 06:04 pm
When Musk tweeted a few days ago "If fate is on our side, it will be amazing", maybe this is what he was referring to.
Title: Re: Fairing reuse
Post by: NX-0 on 03/30/2017 06:53 pm
How fast is the fairing going when it splashes now? The shape creates some drag. How slow does a fairing have to be to withstand damage at splash?

Also, it's odd how, when I heard "inflatable," I was thinking something completely different than the rest of you.
Suppose that inside the fairing wall you installed a deflated "beach ball".
As the fairing tumbled and fell through the atmosphere, at some point, the beach ball would inflate. This would increase drag significantly.
At splash, it also makes it very buoyant. It just rides the waves until someone comes and gets it.
Title: Re: Fairing reuse
Post by: Kaputnik on 03/30/2017 07:20 pm
How fast is the fairing going when it splashes now? The shape creates some drag. How slow does a fairing have to be to withstand damage at splash?

Also, it's odd how, when I heard "inflatable," I was thinking something completely different than the rest of you.
Suppose that inside the fairing wall you installed a deflated "beach ball".
As the fairing tumbled and fell through the atmosphere, at some point, the beach ball would inflate. This would increase drag significantly.
At splash, it also makes it very buoyant. It just rides the waves until someone comes and gets it.

Except Gwynne Shotwell has explicitly stated that they will not be getting the fairings wet.
Title: Re: Fairing reuse
Post by: envy887 on 03/30/2017 07:21 pm
How fast is the fairing going when it splashes now? The shape creates some drag. How slow does a fairing have to be to withstand damage at splash?

Also, it's odd how, when I heard "inflatable," I was thinking something completely different than the rest of you.
Suppose that inside the fairing wall you installed a deflated "beach ball".
As the fairing tumbled and fell through the atmosphere, at some point, the beach ball would inflate. This would increase drag significantly.
At splash, it also makes it very buoyant. It just rides the waves until someone comes and gets it.

Musk said a while ago that they were going to try steerable parachutes, and Shotwell said a few weeks ago that they don't want to get the fairings wet.

Maybe they will have both an inflatable and a chute on the fairing, but I have a hard time seeing anything like that keeping it totally out of the water.
Title: Re: Fairing reuse
Post by: vanoord on 03/30/2017 07:31 pm
Just getting the thing down in one piece would be an achievement, even if it got wet at the end - that's how they started with F9.
Title: Re: Fairing reuse
Post by: Chris_Pi on 03/30/2017 07:33 pm
Musk said a while ago that they were going to try steerable parachutes, and Shotwell said a few weeks ago that they don't want to get the fairings wet.

Maybe they will have both an inflatable and a chute on the fairing, but I have a hard time seeing anything like that keeping it totally out of the water.

Don't think packing enough airbags into the fairing to make it it's own boat is practical, So:

Flyback to land - Probably can't cover the distance.

Landing on barge/ship - Needs to be pretty accurate and haven't seen anything other than the usual support ships, But a plain old deck cargo barge is all that's likely needed. Rent a couple for a week or so and throw some big airbags on top as cushions.

Mid-air snag with aircraft -  Not much anyone would know about publicly until a helicopter flies past trailing a fairing half behind. Wait and see.

Title: Re: Fairing reuse
Post by: CraigLieb on 03/30/2017 07:43 pm
I'm sticking with the airship with a cargo hold model till they tell me otherwise..
You KNOW he has to have a secret island somewhere too... right!
Title: Re: Fairing reuse
Post by: AncientU on 03/30/2017 08:14 pm
Secret Island is my bet, too.

Since so many eyes are on this launch, though, they might forego the real plan and snag the steerable gliders from a 'civilian' base in the Bahamas (Marsh Harbor).
Title: Re: Fairing reuse
Post by: vanoord on 03/30/2017 08:35 pm

Don't think packing enough airbags into the fairing to make it it's own boat is practical, So:

Not a thoroughly daft idea, but it might add 200kg to each fairing.

I reckon any decent inflatable boat / liferaft manufacturer would be able to make a deployable 'boat' that could be popped out from the outside of the fairing and rapidly inflated just before touchdown under parachute, but the weight gain might equate to the loss of the booster core. Which is less than ideal.

I'm also unconvinced that even with some sort of pop-out liferaft the fairing would remain dry in the sort of conditions we've seen stages land in.
Title: Re: Fairing reuse
Post by: john smith 19 on 03/30/2017 10:59 pm
I take it SX have not released a nifty little video of their plans. That is curiously shy of them :)

Well assuming you're going to do it I guess a key question would be do you want the segments together or apart?

Historically they've separated. Those segments don't look very stable so how do you stabilize them to minimize damage from high speed airflow. While the look sort of canoe shaped they are a canoe with  no back, so likely to be quite flimsy. Despite their high surface area they are still likely to be moving too fast to survive if they hit the water without something to slow them down.

Then how do you recover them? Mid air capture?  Helium balloon?

Title: Re: Fairing reuse
Post by: Kabloona on 03/30/2017 11:57 pm
Chris Gebhardt reporting pic of SES-10 fairing has been shown intact floating on ocean after splashdown.
Title: Re: Fairing reuse
Post by: Lars-J on 03/30/2017 11:59 pm
Chris Gebhart reporting fairing has been recovered.

 :o Cool!
Title: Re: Fairing reuse
Post by: Chris Bergin on 03/31/2017 12:00 am
BREAKING news:  Payload fairing LANDED SUCCESSFULLY.  Fairing has thruster systems and steerable parachute.  Was just shown pic of intact fairing floating in ocean.

Wowzers.
Title: Re: Fairing reuse
Post by: Dao Angkan on 03/31/2017 12:25 am
Wow! If they can ocean land succesfully then landing on an ocean based platform might seem plausible. What an awesome mission!
Title: Re: Fairing reuse
Post by: john smith 19 on 03/31/2017 12:46 am
BREAKING news:  Payload fairing LANDED SUCCESSFULLY.  Fairing has thruster systems and steerable parachute.  Was just shown pic of intact fairing floating in ocean.

Wowzers.
Very impressive.

Does anyone have any idea what one of these fairing costs? IIRC they were made by a Swiss company, but I'm not sure if SX brought their mfg in house.
Title: Re: Fairing reuse
Post by: Dao Angkan on 03/31/2017 12:55 am
In the press conference Musk said they'll try to land it on a "bouncy castle" (inflatable).
Title: Re: Fairing reuse
Post by: Dao Angkan on 03/31/2017 12:56 am
BREAKING news:  Payload fairing LANDED SUCCESSFULLY.  Fairing has thruster systems and steerable parachute.  Was just shown pic of intact fairing floating in ocean.

Wowzers.
Very impressive.

Does anyone have any idea what one of these fairing costs? IIRC they were made by a Swiss company, but I'm not sure if SX brought their mfg in house.

In the press conference Musk said $6 million.
Title: Re: Fairing reuse
Post by: Lar on 03/31/2017 12:59 am
So this pair of fairings (floating at sea) was perhaps analogous to the first F9 S1 that "landed" in the ocean... and perhaps we'll see more leased barges equipped for fairing recovery duty?

The SpaceX flotilla is going to need a flagship and an Admiral :)

Has anyone run calcs on the kg ratio? (1kg of S2 mass is one less kg of payload mass, but one kg of additional fairing mass is less than 1g of lost payload because the fairings are ejected early, but it's not the same ratio as S1 mass which is more like 10:1 I think?) Maybe I missed it?

Also ...  AFRS??? (Automated Fairing Recovery Ship)
Title: Re: Fairing reuse
Post by: Joel on 03/31/2017 01:06 am
How far from the drone ship should one expect the fairing to splash down? With a reasonable glide ratio, could it splash down next to it?
Title: Re: Fairing reuse
Post by: john smith 19 on 03/31/2017 01:17 am
In the press conference Musk said $6 million.
Interesting.

When Shotwell was talking about a fully reusable F9 she said they were looking to lower prices to about $6m

Obviously you can't do that if just the fairing replacement eats that up.  :(

With this as 10% of your retail price something will have to be done.

Title: Re: Fairing reuse
Post by: Geron on 03/31/2017 01:19 am
At my SpaceX tour it was explained that the fairings were very expensive and difficult to manufacture. It was either 3.5 or 7 million at that time. I'm not sure if 3.5 was for one clamshell or both.

It's possible the cost has dropped since then though...
Title: Re: Fairing reuse
Post by: virnin on 03/31/2017 01:33 am
BREAKING news:  Payload fairing LANDED SUCCESSFULLY.  Fairing has thruster systems and steerable parachute.  Was just shown pic of intact fairing floating in ocean.

Wowzers.

Maybe this is what SES gets in their Board Room?  ;)  (Yes, that would need a really BIG board room!)
Title: Re: Fairing reuse
Post by: Lar on 03/31/2017 01:34 am
Maybe this is what SES gets in their Board Room?  ;)  (Yes, that would need a really BIG board room!)

It's already got their logo on it... :)
Title: Re: Fairing reuse
Post by: chad1011 on 03/31/2017 01:37 am
It would make on heck of a boardroom table....
Title: Re: Fairing reuse
Post by: TrevorMonty on 03/31/2017 01:38 am
.
Title: Re: Fairing reuse
Post by: Dao Angkan on 03/31/2017 02:05 am
In the press conference Musk said $6 million.
Interesting.

When Shotwell was talking about a fully reusable F9 she said they were looking to lower prices to about $6m

Obviously you can't do that if just the fairing replacement eats that up.  :(

With this as 10% of your retail price something will have to be done.

He also joked(?) about despite not designing the second stage to return that maybe they should attempt to anyway as nothing to lose. He can sound mischievous at times, but there's usually some basis to what he says, so maybe they'll start to experiment with the second stage?
Title: Re: Fairing reuse
Post by: ClayJar on 03/31/2017 02:06 am
Maybe this is what SES gets in their Board Room?  ;)  (Yes, that would need a really BIG board room!)

It's already got their logo on it... :)

In the presser, Martin Halliwell laughed that it was the wrong half (with the American flag instead of SES's logo).  From the sound of it, the photo was of one half.  I wonder if they had recovery hardware on both halves or just on one half (for a control test from space down to a water landing).
Title: Re: Fairing reuse
Post by: Dao Angkan on 03/31/2017 02:12 am
Musk following on from fairing recovery;

Quote
Then the only thing left is the upper stage. We didn't originally intend for Falcon 9 to have a reusable upper stage, but it might be fun to try a Hail Mary and you know, what's the worst thing that can happen? It blows up. You know, It blows up anyway.
Title: Re: Fairing reuse
Post by: manoweb on 03/31/2017 02:15 am
I cannot express how excited I am for this dream that is becoming true. Fairing recovery! So many dismissed this idea as impossible, especially on this flight. I cannot wait to see images and know more details, but apparently what we know now is:
- thrusters
- automated parachutes
- in the future, some sort of floating structure to keep it dry
- we also know that it landed close enough to some support boat that they were able to shoot a picture of it about an hour from separation

I hope we will see soon what is the trajectory of the fairings during their descent.
Title: Re: Fairing reuse
Post by: Dao Angkan on 03/31/2017 02:18 am
Maybe this is what SES gets in their Board Room?  ;)  (Yes, that would need a really BIG board room!)

It's already got their logo on it... :)

In the presser, Martin Halliwell laughed that it was the wrong half (with the American flag instead of SES's logo).  From the sound of it, the photo was of one half.  I wonder if they had recovery hardware on both halves or just on one half (for a control test from space down to a water landing).

That makes sense, no need to double the extra weight when you only need to bring one back to prove the feasibility.
Title: Re: Fairing reuse
Post by: rsdavis9 on 03/31/2017 02:27 am
Did he really say bouncy house? I said that upthread a ways.
Title: Re: Fairing reuse
Post by: meekGee on 03/31/2017 02:28 am
Maybe this is what SES gets in their Board Room?  ;)  (Yes, that would need a really BIG board room!)

It's already got their logo on it... :)

Very good observation there.  A no-brainer if you think about it.

EDIT:

... and if they got the wrong half, at least a bumper sticker: "The other half says SES on it"
Title: Re: Fairing reuse
Post by: ClayJar on 03/31/2017 02:34 am
https://youtu.be/jC3LQFpuzqs

Fairing recovery starts at 12:05 when a guy walks in and shows Elon the photo of the floating fairing.

Did he really say bouncy house? I said that upthread a ways.

14:16 "So, what we'll have is kinda like a bouncy castle for it to land on."
Title: Re: Fairing reuse
Post by: Galactic Penguin SST on 03/31/2017 02:40 am
Do we know how intact the fairing is on the sea? If you check out the Chinese rockets threads you will see multiple examples of the fairing making back on land relatively intact, but I am sure no one will like to use them back.  ;)
Title: Re: Fairing reuse
Post by: Space Ghost 1962 on 03/31/2017 03:28 am
Today's was a test of the concept. Soft landed a fairing half at a known location.

Ariane, Soyuz, and others have by accident recovered fairings mostly intact. The difference here is deterministic result with controlled flight and a means to direct recovery to a specific location.

Next time its done you get both fairings recovered and dry.

The best benefit of this success is that it will lower the time it will take to recover the cost of reuse, because the increment of payoff has grown.
Title: Re: Fairing reuse
Post by: CameronD on 03/31/2017 06:01 am
Finally, Go Searcher has a trophy to bring home..  :)
Title: Re: Fairing reuse
Post by: darkenfast on 03/31/2017 06:30 am
"Look, Ma!  I caught a big one!"
Title: Re: Fairing reuse
Post by: manoweb on 03/31/2017 07:05 am
Anyway - has anybody seen this image with the landed fairing? Or was it only shown to Mr. E. Musk during the press conference and never shown to the public, yet?
Title: Re: Fairing reuse
Post by: Lars-J on 03/31/2017 07:27 am
I guess the fairing landed, but was not recovered. (sunk before they could get to it?)
https://twitter.com/SpaceBrendan/status/847599001746644996
Quote
Brendan Byrne @SpaceBrendan
Musk: Correction, not recovered, but it was directed to a landing area. Will have "bouncy" castle soon.

Aha! So it looks like my guess that they will try to land it on an inflated surface was correct.  8)
Title: Re: Fairing reuse
Post by: john smith 19 on 03/31/2017 07:42 am
Thinking about faring reuse raises some interesting questions.

Historically there seems to have been a fair bit of customizing on the fairing for each payload. Custom sized (and shaped) doors and access panels. Specialized fluid and electrical connectors and windows for RF and various optical wavelengths.  I think they've been a nice options-at-extra-cost addition to the basic launch service for all LV mfgs.

In principle any fairing could wrap any payload, since they all have basically the same interior, but those different fittings will change the mechanical properties a bit. Any given hole is a potential stress concentrator so increase the risk of failure.  There is also the issue that composite structures can suffer impact damage leading to 30% loss of strength with no visible damage (NASA COPV tests).

The upside is that not being a closed surface (more like 2 canoes with the tails chopped off) the two halves can absorb a lot of stress by flexing in a wide variety of modes during the re entry.

So the question is will SX continue the practice of customized PLF's, and if so do customers get to choose which ones are used.Likewise if they chose the "no special mods" option do they get a stock PLF, or just get the next one that's available, regardless of what fittings are on it, as it's good enough to do the job?

BTW
First attempted PLF recovery (but plenty of data collected)

First re-flight of booster stage

First ground test of a new nuclear reactor designed for space in 7 decades (Kilopower in November)

2017 is looking to be an exciting year.  With luck it will also see SLC 40 working again and the long awaited FH maiden flight.

Title: Re: Fairing reuse
Post by: Lars-J on 03/31/2017 07:53 am
So the question is will SX continue the practice of customized PLF's, and if so do customers get to choose which ones are used.Likewise if they chose the "no special mods" option do they get a stock PLF, or just get the next one that's available, regardless of what fittings are on it, as it's good enough to do the job?

I don't think SpaceX customizes their PLF's. (unless I am mistaken) There is only one model available.
Title: Re: Fairing reuse
Post by: woods170 on 03/31/2017 09:36 am
Thinking about faring reuse raises some interesting questions.

Historically there seems to have been a fair bit of customizing on the fairing for each payload. Custom sized (and shaped) doors and access panels.

SpaceX doesn't do customized fairings (yet). "Historically" applies to other LSP's.
Title: Re: Fairing reuse
Post by: Welsh Dragon on 03/31/2017 09:41 am
So the question is will SX continue the practice of customized PLF's, and if so do customers get to choose which ones are used.Likewise if they chose the "no special mods" option do they get a stock PLF, or just get the next one that's available, regardless of what fittings are on it, as it's good enough to do the job?

I don't think SpaceX customizes their PLF's. (unless I am mistaken) There is only one model available.
I think the customisation here would be adding the recovery mods. So in a sense you'd have two models, with or without those mods.
Title: Re: Fairing reuse
Post by: rpapo on 03/31/2017 10:19 am
I don't think SpaceX customizes their PLF's. (unless I am mistaken) There is only one model available.
"Any customer can have a car painted any color that he wants so long as it is black."  -- Henry Ford
Title: Re: Fairing reuse
Post by: Robotbeat on 03/31/2017 11:24 am
Did he really say bouncy house? I said that upthread a ways.
"Bouncy castle" and he said it with a straight face and no one else laughed. 😂
Title: Re: Fairing reuse
Post by: john smith 19 on 03/31/2017 11:30 am
Thinking about faring reuse raises some interesting questions.

Historically there seems to have been a fair bit of customizing on the fairing for each payload. Custom sized (and shaped) doors and access panels.

SpaceX doesn't do customized fairings (yet). "Historically" applies to other LSP's.
Interesting. I recalled both Orbital (for Pegasus) and ULA offering PLF mods for various services and assumed it was SOP for all LV mfgs.

Keeping them standardized let's them do a batch and allow them them to swap PLF's round if one is damaged.

I note it took them a year to re-fly a first stage. Obviously a PLF is simpler but they still need to recover one intact. AIUI they were only trying to recover one of the pair of segments. My guess would be their next attempt will be for both halves to get a full set.

This is clearly the start of a journey. I think they will want to accumulate quite a lot of PLF's before they start re-flying.

It's interesting to ask if this could have been done decades ago if anyone was prepared to do so, or if only the advent of small, powerful GNC hardware has allowed something this complex to be flown.
Title: Re: Fairing reuse
Post by: john smith 19 on 03/31/2017 11:35 am
Did he really say bouncy house? I said that upthread a ways.
"Bouncy castle" and he said it with a straight face and no one else laughed. 😂
That suggests either an inflatable structure draped over the ADRS or an even bigger "crash mat" towed behind it.


Either is quite possible, provided you can deliver enough air flow to keep the structure a couple of psi above atmospheric.  It should (in principle) allow a smaller parachute on thePLF, which is clearly a good thing, given how close the PLF gets to orbit.
Title: Re: Fairing reuse
Post by: JamesH65 on 03/31/2017 11:49 am
I'm assuming something along these lines

https://www.youtube.com/watch?v=j9QrKzLVujs

Title: Re: Fairing reuse
Post by: Jcc on 03/31/2017 12:03 pm
I'm assuming something along these lines

https://www.youtube.com/watch?v=j9QrKzLVujs

Yes, only considerably larger than a bus, and floating in the ocean. And probably they need 2 of them. Then, visit with a ship with a crane, pick them up and put them on the deck, deflate and retrieve the "bouncy castle". All in a day's work.

Maybe they stay close together with the ship. Not much danger to the crew if they stay sheltered when they land. Or, possibly already on the deck. If the ship is big enough, it can hold 2 bouncy castles.
Title: Re: Fairing reuse
Post by: rpapo on 03/31/2017 12:06 pm
Yes, only considerably larger than a bus, and floating in the ocean. And probably they need 2 of them. Then, visit with a ship with a crane, pick them up and put them on the deck, deflate and retrieve the "bouncy castle". All in a day's work.

Maybe they stay close together with the ship. Not much danger to the crew if they stay sheltered when they land. Or, possibly already on the deck. If the ship is big enough, it can hold 2 bouncy castles.
Since the fairing descends without a tail of flame, if the landing is reasonably accurate, it may be possible for the tender to be closer than the tugs are at present to the ASDS.
Title: Re: Fairing reuse
Post by: rsdavis9 on 03/31/2017 12:47 pm
I think 2 separate barges with air bags on deck for the landing. Maybe transfer after landing to one ship to make fast trip back to land. Could even keep barges out there instead of making trip back and forth withlong trip back with barge.
Title: Re: Fairing reuse
Post by: matthewkantar on 03/31/2017 01:21 pm
Is anyone else surprised the fairing sank? They were close enough to photograph it, they didn't have the gear to retrieve it? Also, isn't it filled with air pockets from the construction method? A sizable piece floated to the Bahamas not so long ago.

Matthew
Title: Re: Fairing reuse
Post by: AncientU on 03/31/2017 01:46 pm
Did he really say bouncy house? I said that upthread a ways.
"Bouncy castle" and he said it with a straight face and no one else laughed. 😂

We're well past the laughing stage...

Quote
First they ignore you, then they laugh at you, then they fight you, then you win*.
-- Mahatma Gandhi

https://www.brainyquote.com/quotes/quotes/m/mahatmagan103630.html

* We are here.
Title: Re: Fairing reuse
Post by: sghill on 03/31/2017 01:50 pm
I fly paraplanes and paragliders. The control mechanism setup is be very easy and cheap for a steerable parachute (parafoil).

Parafoils use wing warping for heading changes and throttle or thermals for altitude changes. One servo with a capstan holding both control wires will provide perfect directional control. Pulling on one set of risers while  releasing the other set is how control is maintained. Pitch is mostly irrelevant with a parafoil, and altitude can be bled off by circling as needed. 

They can circle down and fly the shell halves back towards shore remotely for helicopter pickup just off the coast or airbag landing in the water (Elon's "bouncy house").  Or just land them right in the brush at LZ-1. They are going to want a fairly low glide ratio (like 2:1 or 3:1) because the huge surface area of the aeroshell half underneath that is also catching the wind.
Title: Re: Fairing reuse
Post by: Norm38 on 03/31/2017 02:03 pm
Of the next 4 launches, two are RTLS, two are expendable.  So OCISLY is going to be mighty bored with nothing to do.  So maybe they'll use it to land fairings on?
Title: Re: Fairing reuse
Post by: padrat on 03/31/2017 03:03 pm
So the question is will SX continue the practice of customized PLF's, and if so do customers get to choose which ones are used.Likewise if they chose the "no special mods" option do they get a stock PLF, or just get the next one that's available, regardless of what fittings are on it, as it's good enough to do the job?

I don't think SpaceX customizes their PLF's. (unless I am mistaken) There is only one model available.

There isn't really much customization done to the fairings. We're working towards keeping them very generic, obviously an advantage when you want to eventually reuse them. The goal, at least for the commercial customers, is to get to a basic universal design where the only differences are the logo and antenna setup. The most customization gets done to the payload adapter, of course. But yet, even those are surprisingly the same few basic setups (mostly)
Title: Re: Fairing reuse
Post by: cscott on 03/31/2017 03:11 pm
Is anyone else surprised the fairing sank? They were close enough to photograph it, they didn't have the gear to retrieve it? Also, isn't it filled with air pockets from the construction method? A sizable piece floated to the Bahamas not so long ago.

Matthew
We don't know exactly what the photo was: it's possible it was a "chutes out but not yet in contact with ocean" shot from a considerable distance, like we get of dragon recovery.  The fairing could easily have broken apart on contact w the ocean surface, plus night was falling so it could be difficult to find the pieces once the recovery ship gets to the last known position, in darkness.

I bet they've got good video/telemetry, though, so they should know exactly what happened, how close they got to their aim point, etc.
Title: Re: Fairing reuse
Post by: launchwatcher on 03/31/2017 03:15 pm
Thinking about faring reuse raises some interesting questions.

Historically there seems to have been a fair bit of customizing on the fairing for each payload. Custom sized (and shaped) doors and access panels.

SpaceX doesn't do customized fairings (yet). "Historically" applies to other LSP's.
In 2015 at least they offered a little bit of customization.   The user guide says:
Quote
The fairing can accommodate up to two access doors in the cylindrical portion as a standard service. The
standard payload fairing door is elliptical, with a maximum size of 450 x 550 mm (17.7 x 21.7 in.).

Through-fairing RF antenna (re-radiation) systems are available as a nonstandard service; they are
intended for use during payload antenna testing while on the launch pad, not for use during flight.
(top of page 37 of http://www.spacex.com/sites/spacex/files/falcon_9_users_guide_rev_2.0.pdf)
Title: Re: Fairing reuse
Post by: cscott on 03/31/2017 03:27 pm
Thinking about faring reuse raises some interesting questions.

Historically there seems to have been a fair bit of customizing on the fairing for each payload. Custom sized (and shaped) doors and access panels.

SpaceX doesn't do customized fairings (yet). "Historically" applies to other LSP's.
In 2015 at least they offered a little bit of customization.   The user guide says:
Quote
The fairing can accommodate up to two access doors in the cylindrical portion as a standard service. The
standard payload fairing door is elliptical, with a maximum size of 450 x 550 mm (17.7 x 21.7 in.).

Through-fairing RF antenna (re-radiation) systems are available as a nonstandard service; they are
intended for use during payload antenna testing while on the launch pad, not for use during flight.
(top of page 37 of http://www.spacex.com/sites/spacex/files/falcon_9_users_guide_rev_2.0.pdf)
Padrat is a SpaceX employee. His post is definitive.
Title: Re: Fairing reuse
Post by: CharlieWildman on 03/31/2017 03:36 pm
I fly paraplanes and paragliders. The control mechanism setup is be very easy and cheap for a steerable parachute (parafoil).

Parafoils use wing warping for heading changes and throttle or thermals for altitude changes. One servo with a capstan holding both control wires will provide perfect directional control. Pulling on one set of risers while  releasing the other set is how control is maintained. Pitch is mostly irrelevant with a parafoil, and altitude can be bled off by circling as needed. 

They can circle down and fly the shell halves back towards shore remotely for helicopter pickup just off the coast or airbag landing in the water (Elon's "bouncy house").  Or just land them right in the brush at LZ-1. They are going to want a fairly low glide ratio (like 2:1 or 3:1) because the huge surface area of the aeroshell half underneath that is also catching the wind.

I wonder how long it took for the fairing halves to reach the water.  If under a parafoil obliviously significantly longer than the booster.  Maybe there would be enough time to safe the booster, attach Rumba, scooch the booster to one end of the ASDS then inflate a bouncy house and land the fairings. Just a crazy idea.
Title: Re: Fairing reuse
Post by: JasonAW3 on 03/31/2017 03:49 pm
Is anyone else surprised the fairing sank? They were close enough to photograph it, they didn't have the gear to retrieve it? Also, isn't it filled with air pockets from the construction method? A sizable piece floated to the Bahamas not so long ago.

Matthew

Even if the didn't, a couple of float bags with CO2 inflation cartridges would't be too hard to rig.  Heck, they could even rig the inflaters to go off when the are immersed in seawater, like the Navy has for their lifeboats.
Title: Re: Fairing reuse
Post by: cscott on 03/31/2017 04:19 pm
Is anyone else surprised the fairing sank? They were close enough to photograph it, they didn't have the gear to retrieve it? Also, isn't it filled with air pockets from the construction method? A sizable piece floated to the Bahamas not so long ago.

Matthew

Even if the didn't, a couple of float bags with CO2 inflation cartridges would't be too hard to rig.  Heck, they could even rig the inflaters to go off when the are immersed in seawater, like the Navy has for their lifeboats.
Float bags don't help you find small pieces in the middle of the Atlantic at night.
Title: Re: Fairing reuse
Post by: Phil Stooke on 03/31/2017 04:23 pm
No... but if it's in one piece it will be there in the morning.
Title: Re: Fairing reuse
Post by: cscott on 03/31/2017 04:29 pm
No... but if it's in one piece it will be there in the morning.
I'm not ruling out seeing pieces return on the deck of Go Searcher.  I think that's consistent with Elon's clarification.

I think you're underestimating the difficulty of finding even a mostly intact fairing half in the middle of the ocean if telemetry ceases on impact or after battery exhaustion.
Title: Re: Fairing reuse
Post by: Paul_G on 03/31/2017 05:09 pm
We don't know exactly what the photo was: it's possible it was a "chutes out but not yet in contact with ocean" shot from a considerable distance, like we get of dragon recovery.

Didn't Martin Halliwell joke that it was the wrong half - which I take to mean the half with the SES log on. Presumably the photo must have been taken relatively close for that to be visible?

Paul
Title: Re: Fairing reuse
Post by: mme on 03/31/2017 05:20 pm
Is anyone else surprised the fairing sank? They were close enough to photograph it, they didn't have the gear to retrieve it? Also, isn't it filled with air pockets from the construction method? A sizable piece floated to the Bahamas not so long ago.

Matthew

Even if the didn't, a couple of float bags with CO2 inflation cartridges would't be too hard to rig.  Heck, they could even rig the inflaters to go off when the are immersed in seawater, like the Navy has for their lifeboats.
Gwynne Shotwell has stated that they want to keep them out of the water.  So I believe the next steps will be working toward landing them on something.
Title: Re: Fairing reuse
Post by: cscott on 03/31/2017 05:24 pm
We don't know exactly what the photo was: it's possible it was a "chutes out but not yet in contact with ocean" shot from a considerable distance, like we get of dragon recovery.

Didn't Martin Halliwell joke that it was the wrong half - which I take to mean the half with the SES log on. Presumably the photo must have been taken relatively close for that to be visible?

Paul
Maybe?  Hard to say.  Compare this photo of Dragon, perhaps taken at roughly similar stand-off distance and light. (However, note that dragon landing is at sun*rise*, to give the recovery team maximum working time, while the fairing reentered at sun*set*.)

Now imagine that the fairing was *catching* the light, instead of being silhouetted.  You'd have to make some assumptions about the angle the fairing is held under the parafoil.  I could argue either way.  If things are just right, you might be able to just make out the flag (or, more likely, lack of SES logo).  Or if the conditions are wrong (fairing close to horizontal, fairing in silhouette) I could see how it would be impossible to tell at that distance.

Maybe this actually came up in earlier banter, so the SES CEO knew already that only one half would be recovered, and that it wouldn't be the "right" one, so it didn't have to be visible in the photo either way.
Title: Re: Fairing reuse
Post by: CraigLieb on 03/31/2017 06:06 pm
We are beginning to see the designs of Elon, the evil genius...  (pinkie firmly planted in corner of mouth)

The fairing will deploy cold-gas thrusters and small pop-out grid fins to stabilize into a flyable aeroshell, navigating to a selected capture zone. At which point, the very large airship will open up it's large under slung cargo hold and the fairings will fly in and be caught in nets. The airship will then make its way to Elon's secret volcano lair ... which opens up it's hidden landing pad area, etc. Submarines or fast boats will return the shells to shore for additional processing.

 8)

I was really close here...   
    thrusters (check - sort of)
    flyable aeroshell  (sort of again, check)
    airship = really large bouncy castle  (check)

volcano lair ... welllll, we don't know the whole plan yet, really so I still have a shot.

 8)

Edit/Lar: Followups probably at some point belong in the party thread. That's where I replied anyway... :)
Title: Re: Fairing reuse
Post by: Stan-1967 on 03/31/2017 06:29 pm
If the parafoil can maneuver for a precision landing, I think SpaceX should be able to recover both halves with a single ship or barge.  I envision deploying booms off the starboard & port sides, and each half has it's own landing space.  See the attached image & replace a barge or ship instead of the proud guy who needs floaties in the swimming pool.

The ship or barge in the middle would have a crane or hoist to move the fairing onto the vessel.  It may also be an open question if this method can work like the rocket DPL concept where the barge is at a predetermined GPS coordinate.  This method may require the ship to chase the fairings within the landing ellipse & the fairings may need a way to identify the landing target & self guide.   Not enough information to know what it will be at this point.
Title: Re: Fairing reuse
Post by: rsdavis9 on 03/31/2017 07:26 pm
If the parafoil can maneuver for a precision landing, I think SpaceX should be able to recover both halves with a single ship or barge.  I envision deploying booms off the starboard & port sides, and each half has it's own landing space.  See the attached image & replace a barge or ship instead of the proud guy who needs floaties in the swimming pool.

The ship or barge in the middle would have a crane or hoist to move the fairing onto the vessel.  It may also be an open question if this method can work like the rocket DPL concept where the barge is at a predetermined GPS coordinate.  This method may require the ship to chase the fairings within the landing ellipse & the fairings may need a way to identify the landing target & self guide.   Not enough information to know what it will be at this point.

Or the BO method. Moving recovery vessel and bring PLF down on a moving vessel. Vessel could be lots of things...
Title: Re: Fairing reuse
Post by: john smith 19 on 03/31/2017 07:47 pm
There isn't really much customization done to the fairings. We're working towards keeping them very generic, obviously an advantage when you want to eventually reuse them. The goal, at least for the commercial customers, is to get to a basic universal design where the only differences are the logo and antenna setup. The most customization gets done to the payload adapter, of course. But yet, even those are surprisingly the same few basic setups (mostly)
This is one of those odd little quirks that only seems important to space geeks but is actually turning out to be a key to making the reuse of this structure affordable.

I note you specify commercial customers. That suggests govt payloads under the EELV contracts may be more customized. Will that rule out reuse entirely?
Is anyone else surprised the fairing sank? They were close enough to photograph it, they didn't have the gear to retrieve it? Also, isn't it filled with air pockets from the construction method? A sizable piece floated to the Bahamas not so long ago.

Matthew

Even if the didn't, a couple of float bags with CO2 inflation cartridges would't be too hard to rig.  Heck, they could even rig the inflaters to go off when the are immersed in seawater, like the Navy has for their lifeboats.
Float bags don't help you find small pieces in the middle of the Atlantic at night.
The obvious answer to which is of course don't launch at night.  :)

However failing that this has been a problem before. The usual answer are some high intensity low frequency strobe beacons. I'm guessing you could put them in some little fairings on the outside so as the halves floated down their flickering would be seen for miles, barring heavy fog.
Title: Re: Fairing reuse
Post by: CraigLieb on 03/31/2017 07:48 pm
anyone notice the image before fairing release? In hosted webcast? Mission time 3:43
Title: Re: Fairing reuse
Post by: Bargemanos on 03/31/2017 08:37 pm
anyone notice the image before fairing release? In hosted webcast? Mission time 3:43


Just compared with the Echostar 23 launch but didn't find any notable difference.
Title: Re: Fairing reuse
Post by: cscott on 03/31/2017 08:47 pm
We could be looking at the wrong side of the fairing in those pictures.
Title: Re: Fairing reuse
Post by: DAZ on 03/31/2017 09:37 pm
I guess the fairing landed, but was not recovered. (sunk before they could get to it?)
https://twitter.com/SpaceBrendan/status/847599001746644996
Quote
Brendan Byrne @SpaceBrendan
Musk: Correction, not recovered, but it was directed to a landing area. Will have "bouncy" castle soon.

Aha! So it looks like my guess that they will try to land it on an inflated surface was correct.  8)

Your guess and others.
Title: Re: Fairing reuse
Post by: gosink on 04/01/2017 05:38 pm
The following links might be of general interest with respect to the topic of steerable automated parachutes & parafoils: 

https://www.youtube.com/watch?v=iFNFUqIRbkc
https://www.youtube.com/watch?v=yQlj5-aWdSk
Title: Re: Fairing reuse
Post by: savuporo on 04/01/2017 06:48 pm
The following links might be of general interest with respect to the topic of steerable automated parachutes & parafoils:..

https://www.youtube.com/results?search_query=joint+precision+airdrop+system
Title: Re: Fairing reuse
Post by: NX-0 on 04/01/2017 09:23 pm
I guess the fairing landed, but was not recovered. (sunk before they could get to it?)
https://twitter.com/SpaceBrendan/status/847599001746644996
Quote
Brendan Byrne @SpaceBrendan
Musk: Correction, not recovered, but it was directed to a landing area. Will have "bouncy" castle soon.

Aha! So it looks like my guess that they will try to land it on an inflated surface was correct.  8)

I was told by one of the fairing recovery engineers this morning the fairing was recovered.
"It was recovered and hoisted into the boat."
Confirmed they only experiment with one piece of the fairing at a time.
Problem, I was told, is that some of the 'chute lines used for steering broke.

This is the first time I have had anything close to first-hand information like this.
Title: Re: Fairing reuse
Post by: cppetrie on 04/01/2017 09:26 pm
I guess the fairing landed, but was not recovered. (sunk before they could get to it?)
https://twitter.com/SpaceBrendan/status/847599001746644996
Quote
Brendan Byrne @SpaceBrendan
Musk: Correction, not recovered, but it was directed to a landing area. Will have "bouncy" castle soon.

Aha! So it looks like my guess that they will try to land it on an inflated surface was correct.  8)

I was told by one of the fairing recovery engineers this morning the fairing was recovered.
"It was recovered and hoisted into the boat."
Confirmed they only experiment with one piece of the fairing at a time.
Problem, I was told, is that some of the 'chute lines used for steering broke.

This is the first time I have had anything close to first-hand information like this.
So Elon probably meant it wasn't recovered in the "we can reuse it" sense but it was recovered in the "we found it and retrieved it" sense
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 04/03/2017 07:22 am
Gwynne Shotwell is speaking at the 33rd Space Symposium on Wednesday. Hopefully there'll be some more info then and at least a photo? Just time to get everything back to port and do some editing prior to the presentation.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 04/03/2017 11:28 am
Possible return of recovered fairing to port? (image re-attached for convenience)

Quote
Scott M‏ @Restrantek 13m13 minutes ago

The Go Searcher is back in port. #SpaceX is there a fairing or portion of under the tarps? Will be docked at SpaceX Barge Dock

https://twitter.com/Restrantek/status/848855345556533248 (https://twitter.com/Restrantek/status/848855345556533248)
Title: Re: Fairing reuse
Post by: Semmel on 04/03/2017 12:51 pm
removed my comment as images show, it was not a April fools joke. Thanks for the info NX-0!
Title: Re: Fairing reuse
Post by: Darga on 04/03/2017 01:36 pm
Loads of pics from Reddit user aftersteveo https://imgur.com/gallery/qa2rB
Title: Re: Fairing reuse
Post by: Wolfram66 on 04/03/2017 01:47 pm
The need to equip or obtain a boat with an A-Frame hoist on the rear like they use to launch ROV's or deep sea research subs. That will make fairing retrieval easier
Title: Re: Fairing reuse
Post by: JamesH65 on 04/03/2017 02:19 pm
The need to equip or obtain a boat with an A-Frame hoist on the rear like they use to launch ROV's or deep sea research subs. That will make fairing retrieval easier

Only if they need to crane out of the water, and they have said they don't want to get it wet.
Title: Re: Fairing reuse
Post by: Wolfram66 on 04/03/2017 02:42 pm
The need to equip or obtain a boat with an A-Frame hoist on the rear like they use to launch ROV's or deep sea research subs. That will make fairing retrieval easier

Only if they need to crane out of the water, and they have said they don't want to get it wet.

Or to get it off the Bouncy Castle
Title: Re: Fairing reuse
Post by: whitelancer64 on 04/03/2017 02:51 pm
Loads of pics from Reddit user aftersteveo https://imgur.com/gallery/qa2rB
Looks like quite a bit of damage! About right for a first try, though, and the real accomplishment is getting them to a pre-determined place where they could be recovered.
Title: Re: Fairing reuse
Post by: JamesH65 on 04/03/2017 02:55 pm
The need to equip or obtain a boat with an A-Frame hoist on the rear like they use to launch ROV's or deep sea research subs. That will make fairing retrieval easier

Only if they need to crane out of the water, and they have said they don't want to get it wet.

Or to get it off the Bouncy Castle

Needs more than an a-frame on the back of a support ship for that.
Title: Re: Fairing reuse
Post by: Lar on 04/03/2017 03:01 pm
The need to equip or obtain a boat with an A-Frame hoist on the rear like they use to launch ROV's or deep sea research subs. That will make fairing retrieval easier

Only if they need to crane out of the water, and they have said they don't want to get it wet.

Or to get it off the Bouncy Castle

Needs more than an a-frame on the back of a support ship for that.

Do that in port. Just cinch it down with cross straps and leave the castle inflated (at least partly) to cushion it where it rests for transport.
Title: Re: Fairing reuse
Post by: mattstep on 04/03/2017 03:03 pm
The need to equip or obtain a boat with an A-Frame hoist on the rear like they use to launch ROV's or deep sea research subs. That will make fairing retrieval easier

Only if they need to crane out of the water, and they have said they don't want to get it wet.

Or to get it off the Bouncy Castle

Do that in port. Just cinch it down with cross straps and leave the castle inflated (at least partly to cushion it where it rests for transport.

Needs more than an a-frame on the back of a support ship for that.

That's assuming the bouncy castle is on the back of a ship. It could be floating on its own and just anchored or tethered to the support ship or ASDS.
Title: Re: Fairing reuse
Post by: AAPSkylab on 04/03/2017 04:17 pm
How about towing a bouncy castle into the wind.

Fairing under parafoil (or stearable parachute) turns into the wind on landing leg.

Similar to landing on aircraft carrier.

Minimize relative horizontal motion at touchdown.
Title: Re: Fairing reuse
Post by: Kaputnik on 04/03/2017 04:32 pm
How about towing a bouncy castle into the wind.

Fairing under parafoil (or stearable parachute) turns into the wind on landing leg.

Similar to landing on aircraft carrier.

Minimize relative horizontal motion at touchdown.

I've done a bit of paragliding in the past, and a steerable foil has fairly limited control available. Obviously as a glider you cannot increase speed or altitude using power, so you need to stay on the 'high side' all the way in.
I was taught to land by making a gentle curving approach towards my LZ. If I felt I was too high, widen the curve to increase the distance travelled. If I thought I was too low, tighten the curve.

I'm not going to say it's impossible to do this manoeuvre onto a moving target, but it kind of makes my head hurt thinking about how you would fly that. But of course the fairings won't be flown by a mere human.
Title: Re: Fairing reuse
Post by: Barrie on 04/03/2017 04:38 pm
Maybe it will be less like a bouncy castle and more like a big lilo, turned up at the sides and at one end.  Like a stylized catcher's mitt.  The fairing approaches from the more open end.
Title: Re: Fairing reuse
Post by: rsdavis9 on 04/03/2017 05:01 pm
Fast catamarans to do the final catch.
What can a cat do on the water and what will a paragliding PLF be doing?
35 knots?
Title: Re: Fairing reuse
Post by: TrevorMonty on 04/03/2017 06:08 pm
Why not bouncing castle on boat in picture, looks big enough. Will need two boats.  At $3m a half fairing they can afford to charter another boat for a few days.
Title: Re: Fairing reuse
Post by: savuporo on 04/03/2017 08:40 pm
... it kind of makes my head hurt thinking about how you would fly that. ..
Eh .. i've done a few swoop landing competitions. Not that i  won a lot, but it's not that hard. A few sky gods i know have done landings in a back of a truck.
Plus, look up thread and read up on what JPADs are doing today fully autonomously.
Title: Re: Fairing reuse
Post by: RDoc on 04/03/2017 08:52 pm
It will be fascinating to see what they use for terminal and landing control.

I suppose that if sports parachutists can land within a few centimeters, a robot system can as well, but my understanding is that military cargo drops using GPS guided automated systems (JPAD) are more like 70m. That's pretty big for a sea going bouncy castle.
Title: Re: Fairing reuse
Post by: savuporo on 04/03/2017 08:58 pm
..t my understanding is that military cargo drops using GPS guided automated systems (JPAD) are more like 70m.

They were. JPADs seem to have evolved significantly since the initial operational capability almost 10 years ago now, specifically around landing with high precision in difficult terrain.
Title: Re: Fairing reuse
Post by: iamlucky13 on 04/04/2017 03:13 am
Very cool to see they recovered a half, even if visibly quite damaged.

No indication the fairing landing was the "fate" referred to earlier, but the successful re-flight was absolutely thrilling,  and seemed in the brief interview immediately afterwards to have left Elon breathless.
Title: Re: Fairing reuse
Post by: deruch on 04/04/2017 03:27 am
Loads of pics from Reddit user aftersteveo https://imgur.com/gallery/qa2rB
Looks like quite a bit of damage! About right for a first try, though, and the real accomplishment is getting them to a pre-determined place where they could be recovered.
I haven't seen any info on how close they came to hitting their target.  I'm trying to get an estimated accuracy for this first attempt.  Clearly they were close enough so that the recovery boat could still get to it before it sank.  Which seems a significant achievement in addition to the feat of it just surviving to sea level, but maybe they are quite buoyant in salt water and this isn't so incredible.  And we know that they got to it at least within the amount of time it took for Elon to mention it at the post-launch briefing (any estimates on how much time this was?).  Hopefully, we'll get some info on just how close they came to the bullseye soon.  I still remember how awesome it was when they added the grid fins to the 1st stage and hit the ASDS on the next try. 
Title: Re: Fairing reuse
Post by: cppetrie on 04/04/2017 03:44 am
Very cool to see they recovered a half, even if visibly quite damaged.

Unfortunately we have no way of knowing how the damage in the pictures was sustained. On descent? On contact with the water? While in the water floating waiting to be picked up? While bringing aboard? Note they don't have the proper lifting equipment on the vessel to lift it out of the water. As others noted, it was probably dragged aboard likely resulting in significant damage.

If it made it through descent without damage and landed where they intended it to land then the effort was wildly successful. If true, all they need is a proper catch vessel (the so called "bouncy house") and they have themselves a fairing recovery system. My guess is that this attempt proved out their concept, and the next attempts will be with catch vessel (perhaps only one for now) and any refinements their data suggests are needed. Once they land a few on a catch vessel they'll be brought back for extensive structural testing and evaluation to determine viability for reuse. With the number of launches they will have coming up in which to make iterations, I won't be the least bit surprised if they are ready to fly reused (flight-proven) fairings on the FH demo or another flight before the end of the year.
Title: Re: Fairing reuse
Post by: meekGee on 04/04/2017 06:07 am
So bouncy house...   On top of a boat, or towed behind it?

Station-keeping, or full-steam into the wind?
Title: Re: Fairing reuse
Post by: cppetrie on 04/04/2017 06:35 am
So bouncy house...   On top of a boat, or towed behind it?

Station-keeping, or full-steam into the wind?
My guess is inflatable cushion on a second ASDS. Depending on accuracy it may be possible to catch both fairings on the same ship. Something on a ship would mean no need to offload at all while at sea. Dragging an inflatable raft of some sort seems unwieldy and problematic. Offloading so raft can be deflated means using a crane, and getting people aboard an inflatable raft in anything other than completely calm seas to secure lift cables seems super sketchy. Also, something being dragged just seems to variable in course and speed to reliably land on. Stationary boat with station-keeping thrusters seems like a better target. Yeah, I think drone ship barge with inflatable pillow on the surface. Inflate. Catch. Deflate. Secure. Tow it home.
Title: Re: Fairing reuse
Post by: JamesH65 on 04/04/2017 11:42 am
So bouncy house...   On top of a boat, or towed behind it?

Station-keeping, or full-steam into the wind?
My guess is inflatable cushion on a second ASDS. Depending on accuracy it may be possible to catch both fairings on the same ship. Something on a ship would mean no need to offload at all while at sea. Dragging an inflatable raft of some sort seems unwieldy and problematic. Offloading so raft can be deflated means using a crane, and getting people aboard an inflatable raft in anything other than completely calm seas to secure lift cables seems super sketchy. Also, something being dragged just seems to variable in course and speed to reliably land on. Stationary boat with station-keeping thrusters seems like a better target. Yeah, I think drone ship barge with inflatable pillow on the surface. Inflate. Catch. Deflate. Secure. Tow it home.

i agree some sort of drone chip with cushions. There is a problem with catching two halves though. Don't want one landing on the other.  Two drones? But of course they don't need to be as tough as the ASDS, so will be a lot cheaper. Could also be manned I suspect, as the fairings are light and have nothing explosive on board. Just need a hardened shelter for personnel.  I like the idea of a large catamaran based platform.
Title: Re: Fairing reuse
Post by: rsdavis9 on 04/04/2017 12:05 pm
Is there any advantage of the cat with cushion matching horizontal velocity with the fairing when landing?
Also given a good eye(from captain) or computers it could make up for targeting accuracy.
Title: Re: Fairing reuse
Post by: sevenperforce on 04/04/2017 12:21 pm
Is there any advantage of the cat with cushion matching horizontal velocity with the fairing when landing?
Also given a good eye(from captain) or computers it could make up for targeting accuracy.
The horizontal velocity will be known ahead of time, so this seems like a good idea. Though it might be greater than what the cat can pull.
Title: Re: Fairing reuse
Post by: Robotbeat on 04/04/2017 12:36 pm
Did he really say bouncy house? I said that upthread a ways.
"Bouncy castle" and he said it with a straight face and no one else laughed. 😂

We're well past the laughing stage...

Quote
First they ignore you, then they laugh at you, then they fight you, then you win*.
-- Mahatma Gandhi

https://www.brainyquote.com/quotes/quotes/m/mahatmagan103630.html

* We are here.
Yeah, but "bouncy castle" is funny! :)
Title: Re: Fairing reuse
Post by: Kaputnik on 04/04/2017 01:00 pm
Is there any advantage of the cat with cushion matching horizontal velocity with the fairing when landing?
Also given a good eye(from captain) or computers it could make up for targeting accuracy.
The horizontal velocity will be known ahead of time, so this seems like a good idea. Though it might be greater than what the cat can pull.

I'm in two minds about this one. There are too many assumptions at work to call it either way.
What speed will the fairings be flying in at? Faster speeds mean smaller chutes and better response to wind shifts and gusts (a fairing half has a lot of surface area for its mass). But slower speeds give better landing survivability.
Boats that are dead in the water can have a horrible motion. Steaming slowly into the waves/swell/wind can help a lot, but going too fast makes for violent slamming.

I think there could be merit in a large inflatable raft (bouncy castle) that is simply allowed to drift with the wind. The wind will be affecting the fairing to a similar degree, not identical though owing to wind gradient and the water drag on the raft.
Title: Re: Fairing reuse
Post by: speedevil on 04/04/2017 01:18 pm
I haven't seen any info on how close they came to hitting their target.  I'm trying to get an estimated accuracy for this first attempt.  Clearly they were close enough so that the recovery boat could still get to it before it sank.  Which seems a significant achievement in addition to the feat of it just surviving to sea level, but maybe they are quite buoyant in salt water and this isn't so incredible.
http://www.bbc.co.uk/news/uk-england-cornwall-34941462
It indeed floats long-term.
(https://ichef-1.bbci.co.uk/news/624/cpsprodpb/5172/production/_86905802_rocketttrescoisland.jpg)
This is a fairing which bobbed along just under/on the surface all the way to the UK.

Though this method of recovery is probably not useful for reflight :)
Title: Re: Fairing reuse
Post by: JamesH65 on 04/04/2017 01:48 pm
I've been pondering, and that fact that the fairings are coming down under parachute will probably mean that whatever they land on will need to be informing them of the wind conditions at the landing site. They will need to come in heading in to wind, so they need to know the exact wind direction to do so. This means comms from the ground to the fairing, which isn't done on the 1st stage since it comes in so fast it doesn't need to worry about wind and can compensate quickly for that it does encounter. I don't think a parachute will have the same level and speed of control, the descent is also much slower so more time to be affected by the wind.





Title: Re: Fairing reuse
Post by: rsdavis9 on 04/04/2017 01:53 pm
will have the same level and speed of control, the descent is also much slower so more time to be affected by the wind.

And more time for a fast boat to move under it. :)
Title: Re: Fairing reuse
Post by: Basto on 04/04/2017 02:20 pm
I have been studying the photos and am curious what people are basing their claims of damage on.

The detail in the photos did not seem to indicate damage to me.  Just wondering what I am missing.
Title: Re: Fairing reuse
Post by: ellindsey on 04/04/2017 02:24 pm
The edge of the fairing facing the camera, sticking out from under the blue tarp, is very clearly broken off.  On some of the photos you can see skin peeled back away from the center of the fairing half.  I don't know if this damage occurred while it was in the water or during the process of pulling it onto the boat, but there is clear mechanical damage.
Title: Re: Fairing reuse
Post by: JamesH65 on 04/04/2017 02:42 pm
will have the same level and speed of control, the descent is also much slower so more time to be affected by the wind.

And more time for a fast boat to move under it. :)

Not sure how close to the coast these things can be flown, but out in the Atlantic, the rather large waves might be an issue with anything too fast, unless it's really big.
Title: Re: Fairing reuse
Post by: Basto on 04/04/2017 02:45 pm
The edge of the fairing facing the camera, sticking out from under the blue tarp, is very clearly broken off.  On some of the photos you can see skin peeled back away from the center of the fairing half.  I don't know if this damage occurred while it was in the water or during the process of pulling it onto the boat, but there is clear mechanical damage.

I went back through all of the photos and am seeing the peeled back shell now. Sometimes hard to get the fine details when looking on my phone. Thanks!
Title: Re: Fairing reuse
Post by: speedevil on 04/04/2017 03:52 pm
The edge of the fairing facing the camera, sticking out from under the blue tarp, is very clearly broken off.  On some of the photos you can see skin peeled back away from the center of the fairing half.  I don't know if this damage occurred while it was in the water or during the process of pulling it onto the boat, but there is clear mechanical damage.
I'm unsure, but the dimensions look off to me, and don't work unless there are several bits, or it's not all there.
Title: Re: Fairing reuse
Post by: Alastor on 04/04/2017 03:54 pm
Any form of moving target would either require precise pre-planning, which doesn't work if you don't compensate the effects of winds, or require real time communication between the target and the fairing.

Comms means more weight, and the risks of communication failiures.
They already avoid doing that for the first stage and use a fixed rendez-vous point instead.

My bet is they will use the same strategy for the fairing, as it removes a lot of requirements and additional failiure modes:  fixed predetermined rendez-vous point.
Title: Re: Fairing reuse
Post by: iamlucky13 on 04/04/2017 05:51 pm
Very cool to see they recovered a half, even if visibly quite damaged.

Unfortunately we have no way of knowing how the damage in the pictures was sustained. On descent? On contact with the water? While in the water floating waiting to be picked up? While bringing aboard? Note they don't have the proper lifting equipment on the vessel to lift it out of the water. As others noted, it was probably dragged aboard likely resulting in significant damage.

True, but the damage looks pretty extensive to me. Depending which end we're looking at (I think aft), either nose or the boat tail seems to be largely broken off. As discussed upthread, the fairing is a much more substantial structure than most people realize. It seems likely to me it sustained non-trivial damage on entry and/or splashdown, and handling it aboard the vessel no doubt made it worse.

I doubt we'll get detailed comments from SpaceX on their findings, but this should be quite helpful to them in understanding what it takes for a fairing to survive.

Note that there have been some references in the past to "Fairing 2.0." Some changes are already in the works, so there could be a major improvement in re-entry performance pending.

By the way, Musk mentioned in the post-launch press conference that the fairing has thrusters to stabilize it during entry. I don't think that had been confirmed before.
Title: Re: Fairing reuse
Post by: OnWithTheShow on 04/05/2017 01:27 am
Why not put the "bouncy castle" in the fairing?
Title: Re: Fairing reuse
Post by: JamesH65 on 04/05/2017 08:45 am
Any form of moving target would either require precise pre-planning, which doesn't work if you don't compensate the effects of winds, or require real time communication between the target and the fairing.

Comms means more weight, and the risks of communication failiures.
They already avoid doing that for the first stage and use a fixed rendez-vous point instead.

My bet is they will use the same strategy for the fairing, as it removes a lot of requirements and additional failiure modes:  fixed predetermined rendez-vous point.

I still cannot see how, without knowing the instantaneous wind conditions at the LZ, how they expect to accurately land under parachute. Remember, parachutes are much more affected by the wind, and have more time to be affected than the 1st stage. You always want to land in to the wind to reduces ground speed, so you NEED to know the wind direction, which could easily have changed between launch and landing.

If you are preprogramming the wind direction, what is the last point at which you can do so? Days in advance? Just prior to launch? There needs to be some mechanism to tell the fairing the wind direction, even before launch.
Title: Re: Fairing reuse
Post by: JJB on 04/05/2017 09:45 am
https://vimeo.com/133990314 (https://vimeo.com/133990314)
Landing on the "Bouncy Castle" Is not that hard, I do this without instruments,with instruments and a 360 overhead even a computer can do this.
Title: Re: Fairing reuse
Post by: JamesH65 on 04/05/2017 09:55 am
https://vimeo.com/133990314 (https://vimeo.com/133990314)
Landing on the "Bouncy Castle" Is not that hard, I do this without instruments,with instruments and a 360 overhead even a computer can do this.

Can you do it so accurately when flying downwind? You clearly turned in to the wind for the final landing approach.
Title: Re: Fairing reuse
Post by: JJB on 04/05/2017 10:03 am
https://vimeo.com/133990314 (https://vimeo.com/133990314)
Landing on the "Bouncy Castle" Is not that hard, I do this without instruments,with instruments and a 360 overhead even a computer can do this.

Can you do it so accurately when flying downwind? You clearly turned in to the wind for the final landing approach.
Thats why you do a 360 turn overhead the target, gps derived wind speed and direction.
Title: Re: Fairing reuse
Post by: Kaputnik on 04/05/2017 11:05 am
Why not put the "bouncy castle" in the fairing?

A big enough inflatable to keep the fairing completely out of the water is probably far too big/heavy to carry on the fairing.
Title: Re: Fairing reuse
Post by: JamesH65 on 04/05/2017 11:27 am
https://vimeo.com/133990314 (https://vimeo.com/133990314)
Landing on the "Bouncy Castle" Is not that hard, I do this without instruments,with instruments and a 360 overhead even a computer can do this.

Can you do it so accurately when flying downwind? You clearly turned in to the wind for the final landing approach.
Thats why you do a 360 turn overhead the target, gps derived wind speed and direction.

Ah ha, thanks for the explanation. That's the missing information.  Question is now -does a falling fairing have enough time to do a 360 loop round the target to assess wind speed/direction. Which is a question we don;t have an answer for without knowing the glide ratio.
Title: Re: Fairing reuse
Post by: speedevil on 04/05/2017 12:01 pm
Ah ha, thanks for the explanation. That's the missing information.  Question is now -does a falling fairing have enough time to do a 360 loop round the target to assess wind speed/direction. Which is a question we don;t have an answer for without knowing the glide ratio.

It doesn't need it - there are various ways of getting live wind data from the landing platform, up to and including a dozen $1K drones standing off 500m and reporting live windspeeds and gusts 10s before they hit.
Title: Re: Fairing reuse
Post by: cppetrie on 04/05/2017 01:49 pm
Ah ha, thanks for the explanation. That's the missing information.  Question is now -does a falling fairing have enough time to do a 360 loop round the target to assess wind speed/direction. Which is a question we don;t have an answer for without knowing the glide ratio.

It doesn't need it - there are various ways of getting live wind data from the landing platform, up to and including a dozen $1K drones standing off 500m and reporting live windspeeds and gusts 10s before they hit.
It also has onboard thrusters that could assist with positioning/trajectory.
Title: Re: Fairing reuse
Post by: kaiser on 04/05/2017 03:31 pm
Ah ha, thanks for the explanation. That's the missing information.  Question is now -does a falling fairing have enough time to do a 360 loop round the target to assess wind speed/direction. Which is a question we don;t have an answer for without knowing the glide ratio.

It doesn't need it - there are various ways of getting live wind data from the landing platform, up to and including a dozen $1K drones standing off 500m and reporting live windspeeds and gusts 10s before they hit.

If you had a good multi-hypothesis navigation filter, you might be able to fairly accurately tell the wind speed just during normal descent based upon the transfer function between your control inputs and positional change during the descent.
Title: Re: Fairing reuse
Post by: Alastor on 04/05/2017 03:33 pm
It also has onboard thrusters that could assist with positioning/trajectory.

I'm not sure using RCS thrusters while hanging from a parafoil is the best of ideas. At best, I would expect it to send you spinning. Also idoubt they have very significant margins on the fuel used. If the system is designed to help for stability and attitude before and during reentry only, expect thet there won't be much propellant left after reentry has occured.
Title: Re: Fairing reuse
Post by: Kaputnik on 04/05/2017 05:00 pm
It also has onboard thrusters that could assist with positioning/trajectory.

I'm not sure using RCS thrusters while hanging from a parafoil is the best of ideas. At best, I would expect it to send you spinning. Also idoubt they have very significant margins on the fuel used. If the system is designed to help for stability and attitude before and during reentry only, expect thet there won't be much propellant left after reentry has occured.

Yup. All you would do is set the fairing swinging or slewing, with little effect on course.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 04/05/2017 06:15 pm
Quote
Shotwell: did recover one half of payload fairing from this launch, not sure about the other. One we did “looked pretty good” #33SS
https://twitter.com/jeff_foust/status/849680344135720960 (https://twitter.com/jeff_foust/status/849680344135720960)

Quote
More fairing recoveries to come from @SpaceX in 2017 #SpaceSymposium #33SS
https://twitter.com/jacoblhacker/status/849680353052831746 (https://twitter.com/jacoblhacker/status/849680353052831746)
Title: Re: Fairing reuse
Post by: JamesH65 on 04/05/2017 07:49 pm
Ah ha, thanks for the explanation. That's the missing information.  Question is now -does a falling fairing have enough time to do a 360 loop round the target to assess wind speed/direction. Which is a question we don;t have an answer for without knowing the glide ratio.

It doesn't need it - there are various ways of getting live wind data from the landing platform, up to and including a dozen $1K drones standing off 500m and reporting live windspeeds and gusts 10s before they hit.

This is clear, but the point is that currently, there is NO apparent transmission from ground to the stage, fairings etc on descent. I personally think simply putting an rx'er on the fairing so it can be told the wind direction is the way to go, but others think that is simply another point of failure. I was simply wondering what alternatives there were.
Title: Re: Fairing reuse
Post by: deruch on 04/06/2017 03:23 am
I haven't seen any info on how close they came to hitting their target.  I'm trying to get an estimated accuracy for this first attempt.  Clearly they were close enough so that the recovery boat could still get to it before it sank.  Which seems a significant achievement in addition to the feat of it just surviving to sea level, but maybe they are quite buoyant in salt water and this isn't so incredible.
http://www.bbc.co.uk/news/uk-england-cornwall-34941462
It indeed floats long-term.

This is a fairing which bobbed along just under/on the surface all the way to the UK.

Though this method of recovery is probably not useful for reflight :)
That's a bit of the interstage, not the fairing.  Though we have also seen fairings washed up in the Bahamas, IIRC.  I know they don't necessarily sink to the bottom of the sea.  The question was more along the lines of how long it will stay on the surface to allow them to be spotted and then recovered.
Title: Re: Fairing reuse
Post by: Steve D on 04/11/2017 07:24 pm
I haven't seen any info on how close they came to hitting their target.  I'm trying to get an estimated accuracy for this first attempt.  Clearly they were close enough so that the recovery boat could still get to it before it sank.  Which seems a significant achievement in addition to the feat of it just surviving to sea level, but maybe they are quite buoyant in salt water and this isn't so incredible.
http://www.bbc.co.uk/news/uk-england-cornwall-34941462
It indeed floats long-term.

This is a fairing which bobbed along just under/on the surface all the way to the UK.

Though this method of recovery is probably not useful for reflight :)
That's a bit of the interstage, not the fairing.  Though we have also seen fairings washed up in the Bahamas, IIRC.  I know they don't necessarily sink to the bottom of the sea.  The question was more along the lines of how long it will stay on the surface to allow them to be spotted and then recovered.

A friend of mine found a large piece of a fairing from an Ariane rocket washed up on the beach in the Yucatan. These things just wont sink.
Title: Re: Fairing reuse
Post by: cartman on 04/22/2017 05:25 pm
Quote
SpaceX‏ Verified account @SpaceX 16m16 minutes ago

View from the fairing during SES-10 mission. #EarthDay pic.twitter.com/zPYQRQ3BkR
Title: Re: Fairing reuse
Post by: CharlieWildman on 04/22/2017 08:48 pm
Quote
SpaceX‏ Verified account @SpaceX 16m16 minutes ago

View from the fairing during SES-10 mission. #EarthDay pic.twitter.com/zPYQRQ3BkR

Really cool.  Probably dumb question... Do we know if this is the half that was recovered? 
Title: Re: Fairing reuse
Post by: cscott on 04/22/2017 10:02 pm
Quote
SpaceX‏ Verified account @SpaceX 16m16 minutes ago

View from the fairing during SES-10 mission. #EarthDay pic.twitter.com/zPYQRQ3BkR

Really cool.  Probably dumb question... Do we know if this is the half that was recovered?
That's probably a safe assumption.  It's also probably a safe assumption that SpaceX has the complete video footage that this frame was taken from.
Title: Re: Fairing reuse
Post by: CharlieWildman on 04/23/2017 02:32 am
Quote
SpaceX‏ Verified account @SpaceX 16m16 minutes ago

View from the fairing during SES-10 mission. #EarthDay pic.twitter.com/zPYQRQ3BkR

Really cool.  Probably dumb question... Do we know if this is the half that was recovered?
That's probably a safe assumption.  It's also probably a safe assumption that SpaceX has the complete video footage that this frame was taken from.

My assumption also.  The instant I saw the image I started looking for hardware that might have been used for recovery.  Not seeing anything obvious I started wondering enough to ask the question.  I do realize that the obvious stuff is probably up near the nose of the fairing and out of sight of the camera.

Here is a comparison showing the SES 10 fairing (inset) and a frame from the video SpaceX released a while back.
Some small differences but I have no idea if they are mission specific or related to recovery.
Title: Re: Fairing reuse
Post by: Comga on 04/23/2017 03:44 am
Quote
SpaceX‏ Verified account @SpaceX 16m16 minutes ago

View from the fairing during SES-10 mission. #EarthDay pic.twitter.com/zPYQRQ3BkR

Really cool.  Probably dumb question... Do we know if this is the half that was recovered? 

I don't know but since they can't broadcast from a fairing half and we know from past recoveries that SpaceX mounts GoPros in fairings, this must be from the recovered half.
Title: Re: Fairing reuse
Post by: hrissan on 04/23/2017 08:46 am
Quote
SpaceX‏ Verified account @SpaceX 16m16 minutes ago

View from the fairing during SES-10 mission. #EarthDay pic.twitter.com/zPYQRQ3BkR
Cute!

Can someone enlighten us what we see? My guess: 3 light tubes in the middle carry compressed gas/liquid to 2 pushers (sticking up from the edges), while black wires carry current to electric latches.

The batteries and gas tank should be at the fairing tip... together with recovery hardware.

Or may be those 3 light "tubes" are actually the paraglider strings attached to fairing aft?
Title: Re: Fairing reuse
Post by: john smith 19 on 04/23/2017 09:02 am
Can someone enlighten us what we see? My guess: 3 light tubes in the middle carry compressed gas/liquid to 2 pushers (sticking up from the edges), while black wires carry current to electric latches.

The batteries and gas tank should be at the fairing tip... together with recovery hardware.

Or may be those 3 light "tubes" are actually the paraglider strings attached to fairing aft?
Yes that seems about right. That would put them behind the camera.

You expect rockets to be quite crammed with equipment but the fairing looks very "clean," with no obvious lumps of hardware bolted on in shot.

That said with the flight path well defined it seems likely you could get away with GPS and some attitude sensors for the fairing to work out when to open 'chutes. While they separate around booster MECO so are a long way from orbit it would still seem like a good idea to keep the weight down.
Title: Re: Fairing reuse
Post by: Lar on 04/23/2017 12:15 pm
Really cool.  Probably dumb question... Do we know if this is the half that was recovered? 

I don't know but since they can't broadcast from a fairing half and we know from past recoveries that SpaceX mounts GoPros in fairings, this must be from the recovered half.

I was ready to fire off a similar post (saying it had to be from the recovered half) when I remembered that vid (that the comparision still came from). Wasn't that transmitted from an unrecovered fairing? If so we can't be sure this still is from the recovered half.

(if it isn't then it's possible not all the equipment is present on this half making our sleuthing harder, LOL)
Title: Re: Fairing reuse
Post by: cscott on 04/23/2017 01:24 pm
Really cool.  Probably dumb question... Do we know if this is the half that was recovered? 

I don't know but since they can't broadcast from a fairing half and we know from past recoveries that SpaceX mounts GoPros in fairings, this must be from the recovered half.

I was ready to fire off a similar post (saying it had to be from the recovered half) when I remembered that vid (that the comparision still came from). Wasn't that transmitted from an unrecovered fairing? If so we can't be sure this still is from the recovered half.

(if it isn't then it's possible not all the equipment is present on this half making our sleuthing harder, LOL)
IIRC the previous video came from an "unrecovered" fairing that happened to wash up on a beach with camera housing intact.
Title: Re: Fairing reuse
Post by: Kaputnik on 04/23/2017 04:09 pm
It's feasible that the Go-Pros are mounted in pods that allow them a decent chance of survival. I mean, I know the standard Go-Pro is pretty tough, but not that tough.
Title: Re: Fairing reuse
Post by: CharlieWildman on 04/23/2017 04:29 pm
It's feasible that the Go-Pros are mounted in pods that allow them a decent chance of survival. I mean, I know the standard Go-Pro is pretty tough, but not that tough.

Go-Pro definitely rides down with the fairing.  Good images of the "beached" fairing and Go-Pro here:  http://www.collectspace.com/ubb/Forum14/HTML/001305.html
Title: Re: Fairing reuse
Post by: Comga on 04/23/2017 04:55 pm
Really cool.  Probably dumb question... Do we know if this is the half that was recovered? 

I don't know but since they can't broadcast from a fairing half and we know from past recoveries that SpaceX mounts GoPros in fairings, this must be from the recovered half.

I was ready to fire off a similar post (saying it had to be from the recovered half) when I remembered that vid (that the comparision still came from). Wasn't that transmitted from an unrecovered fairing? If so we can't be sure this still is from the recovered half.

(if it isn't then it's possible not all the equipment is present on this half making our sleuthing harder, LOL)
IIRC the previous video came from an "unrecovered" fairing that happened to wash up on a beach with camera housing intact.
Precisely
And we did see the protective case for the GoPro in the posts linked above.
The real-time fairing and payload separation videos are broadcast from the second stage.
Title: Re: Fairing reuse
Post by: Lar on 04/23/2017 04:59 pm
thanks for the clarification.
Title: Re: Fairing reuse
Post by: dorkmo on 04/23/2017 06:45 pm
i marked what i thought might be changes
Title: Re: Fairing reuse
Post by: DAZ on 04/23/2017 07:04 pm
In the center green box (the one right across from SES 10) looks like what could possibly be a mortar for the drogue chute in the center. The smaller package could then be the drogue chute with the larger package the parafoil. There appear to be some kind lines from that center box to the 2 boxes that you have marked at the back of the fairing. Could these possibly be the control risers and the motors? The center box leading toward the nose of the fairing that you have marked could possibly be for the risers to the front of the fairing. This would lead toward the nose of the fairing past the center of balance point. At which point they would have to branch off to the 2 sides for attachment points there. The 2 boxes you have marked toward the front could be these 2 attachment points. Alternately the 2 boxes in the front could be the control motors in the 2 to the back could just be the aft attachment points.
Title: Re: Fairing reuse
Post by: OneSpeed on 04/24/2017 01:55 am
By scaling off a few public images, and noting the relative position of the eyelets, here is an estimated lateral view of the new items in the fairing. Of course, there may be more items in the nose.
Title: Re: Fairing reuse
Post by: OneSpeed on 04/24/2017 12:38 pm
Speculation
Title: Re: Fairing reuse
Post by: NX-0 on 05/01/2017 04:36 pm
I received a message from a source this morning that one-half of the NROL-76 fairing parachuted into the ocean was was recovered intact.
No other details yet.
Title: Re: Fairing reuse
Post by: NX-0 on 05/01/2017 04:40 pm
One more tidbit just came through. Accuracy was about 4 miles from target.
Title: Re: Fairing reuse
Post by: cscott on 05/01/2017 06:14 pm
4 miles is far too much for a bouncy castle... would it be close enough for an air recovery? Perhaps fixed-wing?
Title: Re: Fairing reuse
Post by: docmordrid on 05/01/2017 06:18 pm
4 miles is far too much for a bouncy castle... would it be close enough for an air recovery? Perhaps fixed-wing?

Or refine the parafoil's software.
Title: Re: Fairing reuse
Post by: Lar on 05/01/2017 06:23 pm
4 miles is far too much for a bouncy castle... would it be close enough for an air recovery? Perhaps fixed-wing?

Or refine the parafoil's software.

Obvs.

The first fiew landing attempts were misses too. Just not the same kind of miss. But different variables
Title: Re: Fairing reuse
Post by: Rebel44 on 05/01/2017 06:40 pm
One more tidbit just came through. Accuracy was about 4 miles from target.
4 miles from target for both halfs, or just recovered one, or just the one that wasnt recovered?
Title: Re: Fairing reuse
Post by: cscott on 05/01/2017 07:06 pm
I think they are only fitting recovery hardware on one half right now.

Obviously (?) they can improve accuracy in the future. My question was: is it good enough now to start trying to avoid wetting the fairing? Unless they've already firmly decided not to pursue mid-air capture in any circumstances, it seems like they've cleared the blockers from the critical path for that option.
Title: Re: Fairing reuse
Post by: Dao Angkan on 05/01/2017 08:37 pm
A hovercraft could cover 4 miles in a few minutes, it could also self inflate a "bouncy castle". Probably not good in rough seas though.
Title: Re: Fairing reuse
Post by: Doesitfloat on 05/01/2017 09:08 pm
They could just use a speedboat with a winch on the back.
Hook on the the para-foil harness and bring it back like a para sailor.
Title: Re: Fairing reuse
Post by: matthewkantar on 05/01/2017 11:49 pm
They could just use a speedboat with a winch on the back.
Hook on the the para-foil harness and bring it back like a para sailor.

This startling, state of the art digital rendering, along with the screen name "Does It Float" gets a like and a comment.

Matthew
Title: Re: Fairing reuse
Post by: longboard1210 on 05/05/2017 07:29 pm
Any updates on the fairing yet? has it been spotted ? it seems like everyones really tight lipped at the moment about it
Title: Re: Fairing reuse
Post by: leetdan on 05/07/2017 02:17 pm
Go Searcher still hasn't shown up on AIS.  The SES-10 fairing is sitting under tarps next to the Spacehab building, here are some crappy driveby pics I got after the first NROL attempt:

Edit: Go Searcher is back in port.
Title: Re: Fairing reuse
Post by: dorkmo on 05/14/2017 12:09 am
some decent photos of the fairings for F9-FE (Full Expend)

http://forum.nasaspaceflight.com/index.php?topic=42846.msg1677217#msg1677217

the 3rd photo in the set shows a bit of the inside of the male-latch fairing, which i believe is the half that has been used in the recovery attempts

i think the missing section of black square might be the same as this piece seen in the new photo.

also, counting the squares at the base, we wouldnt be able to see the chute bags in this photo if they were there or not
Title: Re: Fairing reuse
Post by: Lars-J on 05/14/2017 12:31 am
F9-FE? Don't make up new abbreviations.
Title: Re: Fairing reuse
Post by: faramund on 05/14/2017 12:35 am
F9-FE? Don't make up new abbreviations.
Is there already an accepted abbreviation for this? If not, I don't see what's wrong with this. How else are new abbreviations established?
Title: Re: Fairing reuse
Post by: old_sellsword on 05/14/2017 01:08 am
F9-FE? Don't make up new abbreviations.
Is there already an accepted abbreviation for this? If not, I don't see what's wrong with this. How else are new abbreviations established?

Why do we need an abbreviation for "expendable?"
Title: Re: Fairing reuse
Post by: dorkmo on 05/14/2017 03:36 am
mostly joking, sorry lol. But it would be interesting if there turns out to be expendable launch scenarios with/without fairing recovery.
Title: Re: Fairing reuse
Post by: Lar on 05/14/2017 05:47 am
(fan)
Let SpaceX decide. We'll try to tease it out and once we do, use it. But making up our own seems a bad idea to me.
Title: Re: Fairing reuse
Post by: Jet Black on 05/14/2017 05:07 pm
They could just use a speedboat with a winch on the back.
Hook on the the para-foil harness and bring it back like a para sailor.

This startling, state of the art digital rendering, along with the screen name "Does It Float" gets a like and a comment.

Matthew

It looks better than most North Korean propaganda photoshops though!
Title: Re: Fairing reuse
Post by: old_sellsword on 05/16/2017 11:35 pm
Elon posted a video (https://www.instagram.com/p/BUK6BQnBNuK) of a fairing post-separation on Instagram:

Quote
Moonlight Sonata

It's from the SES-10 mission. (https://www.instagram.com/p/BTMgPwXFwpY)
Title: Re: Fairing reuse
Post by: mmustapic on 05/17/2017 04:27 pm
From my Instagram feed, Elon posted:

Quote
We did recover the fairing. It has onboard thrusters for positioning in space during reentry and a GPS guided parachute is deployed once it enters the atmosphere
Title: Re: Fairing reuse
Post by: rory on 05/27/2017 05:51 pm
I like the idea that they built a cheap but heavy fairing .... knowing that eventually they would reengineer it with more expensive but lighter materials... more expensive ONCE, yes,  but since now it's recoverable (the mass savings is used for whatever the recovery mechanism is), actually LESS expensive iff they mostly get it back.

they were thinking ahead.

People focus on SpaceX changing plans but they miss that they also have been taking the long view here for a long time.

Also I don't see the need for a lot of heat shielding (said upthread a lot).... These have very low density so terminal velocity is low.

Not sure why I was reading page 30 of this thread earlier this week... but this is contradicted by the video below. Elon explicitly says it's engineered to optimize for mass and claims it may even be the "lightest-weight fairing of its kind."

https://www.youtube.com/watch?v=Nq8HrxfSZMc
Title: Re: Fairing reuse
Post by: Basto on 05/29/2017 06:44 pm
I like the idea that they built a cheap but heavy fairing .... knowing that eventually they would reengineer it with more expensive but lighter materials... more expensive ONCE, yes,  but since now it's recoverable (the mass savings is used for whatever the recovery mechanism is), actually LESS expensive iff they mostly get it back.

they were thinking ahead.

People focus on SpaceX changing plans but they miss that they also have been taking the long view here for a long time.

Also I don't see the need for a lot of heat shielding (said upthread a lot).... These have very low density so terminal velocity is low.

Not sure why I was reading page 30 of this thread earlier this week... but this is contradicted by the video below. Elon explicitly says it's engineered to optimize for mass and claims it may even be the "lightest-weight fairing of its kind."

https://www.youtube.com/watch?v=Nq8HrxfSZMc

I think the key words here are "of its kind".
Title: Re: Fairing reuse
Post by: Lars-J on 05/29/2017 07:44 pm
I like the idea that they built a cheap but heavy fairing .... knowing that eventually they would reengineer it with more expensive but lighter materials... more expensive ONCE, yes,  but since now it's recoverable (the mass savings is used for whatever the recovery mechanism is), actually LESS expensive iff they mostly get it back.

they were thinking ahead.

People focus on SpaceX changing plans but they miss that they also have been taking the long view here for a long time.

Also I don't see the need for a lot of heat shielding (said upthread a lot).... These have very low density so terminal velocity is low.

Not sure why I was reading page 30 of this thread earlier this week... but this is contradicted by the video below. Elon explicitly says it's engineered to optimize for mass and claims it may even be the "lightest-weight fairing of its kind."

https://www.youtube.com/watch?v=Nq8HrxfSZMc

You do realize that this is a 7 yr old video, right? And this was YEARS before the first fairing actually flew, and by that point it had changed a lot. According to people knowledgeable on this forum, the actual flying fairing (not that early prototype) is not the lightest fairing of its kind. It may be the cheapest, but not the lightest.
Title: Re: Fairing reuse
Post by: ChrisC on 05/30/2017 04:47 am
You do realize that this is a 7 yr old video, right?

Worse ... it's a NINE year old video.  It was uploaded (by whomever) in 2010, but was actuully shot in mid 2008.  He refers to Falcon 1 flights 3 and 4 in the future.
Title: Re: Fairing reuse
Post by: darkenfast on 05/30/2017 03:28 pm
Wow, that factory in the video looks really slapdash.  Think they'll ever amount to anything in ten years?  Oh, wait...

Amazing, isn't it, what we have watched happen here over the last decade? 
Title: Re: Fairing reuse
Post by: AncientU on 05/30/2017 06:26 pm
Wow, that factory in the video looks really slapdash.  Think they'll ever amount to anything in ten years?  Oh, wait...

Amazing, isn't it, what we have watched happen here over the last decade?

And EM's net worth was heading below zero about then...  $15B-ish now.
Title: Re: Fairing reuse
Post by: rory on 05/31/2017 04:20 pm
You do realize that this is a 7 yr old video, right? And this was YEARS before the first fairing actually flew, and by that point it had changed a lot. According to people knowledgeable on this forum, the actual flying fairing (not that early prototype) is not the lightest fairing of its kind. It may be the cheapest, but not the lightest.

The point of posting the video wasn't to take Musk's 10-year-old superlatives as gospel. It's evidence that they are in fact using aerospace grade composites, contrary to the speculation that the fairing is heavier because of inexpensive, non-aerospace grade carbon fiber. It lends credence to the explanations (particularly Jim's) that the fairing is heavy for structural reasons (i.e. supporting the payload while horizontal/transitioning to vertical) rather than the use of cheap materials.

Might have helped if I added some of the follow-on discussion to the post I originally quoted:

I don't see any evidence they are using anything other than current state-of-the-art aerospace composites for the fairing.  Let's not pile speculation on speculation.
Of course, there is no evidence they are using state of the art aerospace composites either...unless you want to assume/speculate that they are....;-)
We know the original manufacturer of the fairings was doing current aerospace grade work.  You can speculate that SpaceX simplified or complexified things after they brought manufacturing in-house, but until they do a major fairing redesign Occam's razor would state they are still using something close to standard manufacturing practice for composites.

And SpaceX disclaims any craziness:
Quote
. The fairing is 13.1 meters (43 feet) high and 5.2 meters (17 feet) wide. It consists of an aluminum honeycomb core with carbon-fiber face sheets fabricated in two half-shells.
http://www.spacex.com/news/2013/04/12/fairing

Note: when I say "state-of-the-art" I mean, same as any other current manufacturer would use.  I'm not claiming super secret sauce or unicorn novelty.

It's possible that SpaceX did an about-face and switched materials in the intervening time, but it's certainly a data point in favor of state-of-the-art construction.
Title: Re: Fairing reuse
Post by: leetdan on 06/02/2017 02:54 am
The NROL fairing has been added to the collection at the Spacehab building, in addition to a security fence  8)
Title: Re: Fairing reuse
Post by: OneSpeed on 06/03/2017 10:03 am
The NROL fairing has been added to the collection at the Spacehab building, in addition to a security fence  8)

The fairing appears largely intact, although there is a discontinuity near one of the potential parachute attachment points.
Title: Re: Fairing reuse
Post by: tvg98 on 06/05/2017 09:24 pm
The NROL fairing has been added to the collection at the Spacehab building, in addition to a security fence  8)

So are both halves from NROL-76 or is one from NROL-76 and the other from SES-10?
Title: Re: Fairing reuse
Post by: Jarnis on 06/06/2017 06:29 am
The NROL fairing has been added to the collection at the Spacehab building, in addition to a security fence  8)

So are both halves from NROL-76 or is one from NROL-76 and the other from SES-10?

One per mission - so far only one half of the fairing has featured recovery hardware.
Title: Re: Fairing reuse
Post by: catdlr on 06/21/2017 02:44 am
any of these recent pictures, in this thread, help with determining if this particular faring is set up of reuse capability?

http://forum.nasaspaceflight.com/index.php?topic=43149.msg1692094#msg1692094
Title: Re: Fairing reuse
Post by: cscott on 06/22/2017 04:28 pm
any of these recent pictures, in this thread, help with determining if this particular faring is set up of reuse capability?

http://forum.nasaspaceflight.com/index.php?topic=43149.msg1692094#msg1692094
It's a little suspicious that they never show the full inside of the near fairing half.  The far side fairing I think I can confidently say does not contain the recovery bits we've seen in video.
Title: Re: Fairing reuse
Post by: Jim on 06/22/2017 05:40 pm

It's a little suspicious that they never show the full inside of the near fairing half. 

Propriety hardware
Title: Re: Fairing reuse
Post by: cscott on 06/22/2017 05:46 pm
Yes, my point exactly.  If there is recovery hardware installed, it is on the near side.  Impossible to tell whether it's present or not from these photos.
Title: Re: Fairing reuse
Post by: dorkmo on 06/22/2017 06:32 pm
I think the recovery half has traditionally been the side with the male latches around the seam. So here i believe we are getting a look inside. but I think the past in flight recovery photos showed two seperate internal plumbing raceways, which at firt glave looks like there is only one here?

And no apparent chute bags.

Could the stuff near the top be an area for 3 copv to be mounted? Maybe the fab shop made a reusable half but they later decided not to fit it out with all the plumbing.
Title: Re: Fairing reuse
Post by: old_sellsword on 06/22/2017 06:47 pm
Yes, my point exactly.  If there is recovery hardware installed, it is on the near side.  Impossible to tell whether it's present or not from these photos.

After SES-10, Elon told Martin Halliwell that they recovered the half with the American Flag, not the SES logo (at 12:34 in the video below).

https://www.youtube.com/watch?v=jlF3fmndtY0?t=12m34s

All of these recent encapsulation pictures show the inside of the flag fairing, not the logo fairing (of which we only see the outside).

So we should be able to see recovery hardware if it's installed.
Title: Re: Fairing reuse
Post by: wannamoonbase on 06/22/2017 07:01 pm
Yes, my point exactly.  If there is recovery hardware installed, it is on the near side.  Impossible to tell whether it's present or not from these photos.

Private company, they don't owe us a thing.  We are lucky to get the excellent coverage we do get.

EM is a showman, he has to hold onto somethings to reveal later.
Title: Re: Fairing reuse
Post by: Reflectiv on 06/22/2017 07:08 pm
After SES-10, Elon told Martin Halliwell that they recovered the half with the American Flag, not the SES logo (at 12:34 in the video below).
All of these recent encapsulation pictures show the inside of the flag fairing, not the logo fairing (of which we only see the outside).

So we should be able to see recovery hardware if it's installed.

Quote
Matt Desch‏ @IridiumBoss Jan 14

Great picture of our launch today.  Next time (April) they'll make sure Iridium NEXT logo on fairing pointed my way!
just saying
Title: Re: Fairing reuse
Post by: old_sellsword on 06/22/2017 07:18 pm
After SES-10, Elon told Martin Halliwell that they recovered the half with the American Flag, not the SES logo (at 12:34 in the video below).
All of these recent encapsulation pictures show the inside of the flag fairing, not the logo fairing (of which we only see the outside).

So we should be able to see recovery hardware if it's installed.

Quote
Matt Desch‏ @IridiumBoss Jan 14

Great picture of our launch today.  Next time (April) they'll make sure Iridium NEXT logo on fairing pointed my way!
just saying

I'm not really sure how that's relevant. He's talking about how the on-base viewing areas look south towards the rocket, which means they see the flag half, not the logo half.
Title: Re: Fairing reuse
Post by: dorkmo on 06/22/2017 10:02 pm
Maybe at this point theyre waiting on the bouncy castle before they try any more recoveries.
Title: Re: Fairing reuse
Post by: tvg98 on 06/22/2017 10:14 pm
Maybe at this point theyre waiting on the bouncy castle before they try any more recoveries.

Possibly, but they've still got a lot to work to do if they're missing the landing zones by several miles. I think they might as well take these opportunities to refine their techniques.
Title: Re: Fairing reuse
Post by: cscott on 06/23/2017 02:27 am
If they are not recovering iridium's vandy fairing, perhaps the reason is that Go Searcher is on the east coast. That is, perhaps the recovery effort needs a bit of ground support, and it was not (yet?) worth duplicating or not (yet?) operational on the west coast.
Title: Re: Fairing reuse
Post by: cwr on 06/25/2017 05:25 pm
Noticed this photo of the inside of the flag half of the fairing for the Iridium-2 launch from Vandenberg.
Photo was in a SpaceflightNow Article at https://t.co/IjNnm8ja7B (https://t.co/IjNnm8ja7B)
but was credited to Iridium [its the 7th photo from the top].

https://assets.cdn.spaceflightnow.com/wp-content/uploads/2017/06/25145723/DCySv9CU0AA4XqC.jpg
 (https://assets.cdn.spaceflightnow.com/wp-content/uploads/2017/06/25145723/DCySv9CU0AA4XqC.jpg)

Attached image.

Carl
Title: Re: Fairing reuse
Post by: cscott on 06/25/2017 07:10 pm
Noticed this photo of the inside of the flag half of the fairing for the Iridium-2 launch from Vandenberg.
Photo was in a SpaceflightNow Article at https://t.co/IjNnm8ja7B (https://t.co/IjNnm8ja7B)
but was credited to Iridium [its the 7th photo from the top].

https://assets.cdn.spaceflightnow.com/wp-content/uploads/2017/06/25145723/DCySv9CU0AA4XqC.jpg
 (https://assets.cdn.spaceflightnow.com/wp-content/uploads/2017/06/25145723/DCySv9CU0AA4XqC.jpg)

Attached image.

Carl
Discussed previously in this thread starting here: http://forum.nasaspaceflight.com/index.php?topic=37727.msg1692211.msg#1692211
Title: Re: Fairing reuse
Post by: Silmfeanor on 06/25/2017 09:23 pm
Tweet by Elon:

Quote
@elonmusk
Replying to @BenjaminCoop3

Getting closer to fairing recovery and reuse. Had some problems with the steerable parachute. Should have it sorted out by end of year.

https://twitter.com/elonmusk/status/879085297526464513

Title: Re: Fairing reuse
Post by: iamlucky13 on 06/26/2017 03:39 am
I think the recovery half has traditionally been the side with the male latches around the seam. So here i believe we are getting a look inside. but I think the past in flight recovery photos showed two seperate internal plumbing raceways, which at firt glave looks like there is only one here?

And no apparent chute bags.

Could the stuff near the top be an area for 3 copv to be mounted? Maybe the fab shop made a reusable half but they later decided not to fit it out with all the plumbing.

I also am inclined to suspect the three pairs of u-shaped features could be nests for strapping down gas cylinders.

They probably do any drilling, fastening, and/or bonding to the laminate at the factory, so that should include at least the mounting points for any recovery hardware, if not the some of the mounting features themselves. They might be doing so identically for all fairings for ease of configuration control and ability to re-assign hardware to particular launches as they juggle their schedule.

The rest of the recovery hardware might not be installed until either just before shipping to the launch site, or even at the launch site.

If they're only doing recovery testing at Kennedy, which makes some sense, then here's little reason for the hardware to be installed for a Vandenberg launch.

If they are not recovering iridium's vandy fairing, perhaps the reason is that Go Searcher is on the east coast. That is, perhaps the recovery effort needs a bit of ground support, and it was not (yet?) worth duplicating or not (yet?) operational on the west coast.

Not just GO Searcher, but also the engineers and techs responsible for checkout and maybe installation of the recovery hardware.
Title: Re: Fairing reuse
Post by: cscott on 06/26/2017 12:16 pm
FWIW my new conclusion (after Elon's tweet) is that it's not Go Searcher that's holding things up, but instead that the steerable chute folks had to go back to the drawing board for some part of their system, and the recovery tests are temporarily on hold while they wait for the next-gen chute component to be ready. No sense wasting money testing something they (now) know can't work.
Title: Re: Fairing reuse
Post by: oldAtlas_Eguy on 06/26/2017 04:45 pm
By end of year they will get ~ 6-10 more chances to test. ~3-4 flights will be Dragon flights additional in next 6 months. This give a total for the year of 18 to 23 flights.
Title: Re: Fairing reuse
Post by: wannamoonbase on 06/29/2017 08:12 pm
FWIW my new conclusion (after Elon's tweet) is that it's not Go Searcher that's holding things up, but instead that the steerable chute folks had to go back to the drawing board for some part of their system, and the recovery tests are temporarily on hold while they wait for the next-gen chute component to be ready. No sense wasting money testing something they (now) know can't work.


I mostly agree.  There could be some benefit in flying the halves for re-entry and finding the envelop of what can be done to fly these halves.

More data doesn't hurt.

I'm going to need a video of how the bouncy castle is going to work and how long they will float in the ocean before being retrieved.
Title: Re: Fairing reuse
Post by: ValmirGP on 06/29/2017 11:48 pm
Well, at least now they could theoretically use the landed fairings to test the hardware and software for steering the fairings down with a real article. Since those landed ones are not reusable on a mission, they could always drop them from a plane or helicopter with the revised contraption planned for the recovering until they master the job. And they could test over land also, meaning faster recovery and turn around between trials.
Title: Re: Fairing reuse
Post by: intrepidpursuit on 06/29/2017 11:51 pm
Well, at least now they could theoretically use the landed fairings to test the hardware and software for steering the fairings down with a real article. Since those landed ones are not reusable on a mission, they could always drop them from a plane or helicopter with the revised contraption planned for the recovering until they master the job. And they could test over land also, meaning faster recovery and turn around between trials.

They are sending two fairing halves into space per month right now. I'm not sure adding to that number is worth any effort at all.
Title: Re: Fairing reuse
Post by: Lars-J on 06/29/2017 11:53 pm
Well, at least now they could theoretically use the landed fairings to test the hardware and software for steering the fairings down with a real article. Since those landed ones are not reusable on a mission, they could always drop them from a plane or helicopter with the revised contraption planned for the recovering until they master the job. And they could test over land also, meaning faster recovery and turn around between trials.

They do test already, I'm sure. Do you think they just attach new things to fairings with a "gee-wiz lets see what this does" attitude?
Title: Re: Fairing reuse
Post by: ValmirGP on 06/30/2017 01:07 am
NO, I don't think so. But given the cost of a real fairing, I do believe they tested with some substitute. What I meant is, having a real fairing that was to be sea trash available, they can use those to obtain data from the real article.
Title: Re: Fairing reuse
Post by: rsdavis9 on 06/30/2017 12:31 pm
NO, I don't think so. But given the cost of a real fairing, I do believe they tested with some substitute. What I meant is, having a real fairing that was to be sea trash available, they can use those to obtain data from the real article.

Its also cheaper. No special flights with airplanes/helicopters.
Title: Re: Fairing reuse
Post by: LouScheffer on 07/02/2017 10:43 pm
RUAG just  signed a contract (http://spacenews.com/41132ruag-books-order-for-18-ariane-5-fairings/) for 18 fairings for Ariane 5 for $112M.  That's $6.2M per fairing.   Especially with booster recovery, that's more evidence the fairing is a substantial part of launch cost, and helps explain why SpaceX is trying to recover them (and makes it seem like it's going to be even harder for others to compete on cost, if they don't follow suit).

EDIT:  Sorry, this is an old contract.  I was confused by the July 3rd date.  But the point stands.
Title: Re: Fairing reuse
Post by: TrevorMonty on 07/03/2017 02:37 am
RUAG just  signed a contract (http://spacenews.com/41132ruag-books-order-for-18-ariane-5-fairings/) for 18 fairings for Ariane 5 for $112M.  That's $6.2M per fairing.   Especially with booster recovery, that's more evidence the fairing is a substantial part of launch cost, and helps explain why SpaceX is trying to recover them (and makes it seem like it's going to be even harder for others to compete on cost, if they don't follow suit).

EDIT:  Sorry, this is an old contract.  I was confused by the July 3rd date.  But the point stands.
Fairing recovery is one thing Ariane or ULA could do in near term to help lower launch costs.
Title: Re: Fairing reuse
Post by: GWH on 07/03/2017 03:04 am
Especially for the 5m fairing for ULA.  Go to rocketbuilder.com and check out the price jump from 4m to 5m: $11M difference.

It would be a lesson well spent learning for Vulcan ACES also since that will only fly in 5m variant and stage is fully encapsulated.
Title: Re: Fairing reuse
Post by: Jim on 07/03/2017 06:20 am
ACES is not encapsulated
Title: Re: Fairing reuse
Post by: Rik ISS-fan on 07/03/2017 06:28 am
If I'm not mistaken, RUAG looked earlier to fairing reuse than SpX.
Title: Re: Fairing reuse
Post by: wannamoonbase on 07/13/2017 07:34 pm
Hi All,

Do we know if the 'bouncy castle' has been attempted for a landing yet, or still in development?

Edit: Also, where is it going to housed and deployed from, I can envision several places to store it and have it expand from.  The most water proof, to me, would be on the exterior of the fairing, before expanding and enveloping the fairing.
Title: Re: Fairing reuse
Post by: AC in NC on 07/14/2017 12:30 am
Edit: Also, where is it going to housed and deployed from, I can envision several places to store it and have it expand from.  The most water proof, to me, would be on the exterior of the fairing, before expanding and enveloping the fairing.

Isn't the Bouncy Castle deployed on surface and the parafoil "flies" the fairing into it?
Title: Re: Fairing reuse
Post by: Kabloona on 07/14/2017 12:36 am
Edit: Also, where is it going to housed and deployed from, I can envision several places to store it and have it expand from.  The most water proof, to me, would be on the exterior of the fairing, before expanding and enveloping the fairing.

Isn't the Bouncy Castle deployed on surface and the parafoil "flies" the fairing into it?

Yes, this isn't like a Mars landing where the lander has to carry its own bouncy castle/beach ball.
Title: Re: Fairing reuse
Post by: Lar on 07/14/2017 12:39 am
Edit: Also, where is it going to housed and deployed from, I can envision several places to store it and have it expand from.  The most water proof, to me, would be on the exterior of the fairing, before expanding and enveloping the fairing.

Isn't the Bouncy Castle deployed on surface and the parafoil "flies" the fairing into it?

Yes, this isn't like a Mars landing where the lander has to carry its own bouncy castle/beach ball.
Indeed. Mass spent on recovering the fairing isn't quite as big of an impact to payload mass as mass spent on recovering the second stage, but it's not inconsequential. It's more impact than mass spent on recovering S1
Title: Re: Fairing reuse
Post by: Lars-J on 07/14/2017 01:33 am
Edit: Also, where is it going to housed and deployed from, I can envision several places to store it and have it expand from.  The most water proof, to me, would be on the exterior of the fairing, before expanding and enveloping the fairing.

Isn't the Bouncy Castle deployed on surface and the parafoil "flies" the fairing into it?

There seemed to be people with information who suggested it was carried with the fairing. I can't recall the source, though. A case could be made for either option.
Title: Re: Fairing reuse
Post by: Norm38 on 07/14/2017 02:30 am
A steerable chute system requires guidance, positioning and a lot of control authority. This is all a lot of mass. It may trade better to simply let the fairings land where they may with a drogue and cushion the impact.
But they can only land on the ocean if they aren't steered towards a ship. Do they need airbags if landing in water? If they do land on a ship, what possible benefit is there of them carrying the airbags?
Title: Re: Fairing reuse
Post by: wannamoonbase on 07/14/2017 03:24 am
Edit: Also, where is it going to housed and deployed from, I can envision several places to store it and have it expand from.  The most water proof, to me, would be on the exterior of the fairing, before expanding and enveloping the fairing.

Isn't the Bouncy Castle deployed on surface and the parafoil "flies" the fairing into it?

There seemed to be people with information who suggested it was carried with the fairing. I can't recall the source, though. A case could be made for either option.

Ditto, that's why I asked.

If the Bouncy Castle isn't carried with the fairing then I think it's a pretty safe assumption that the goal would be to prevent the fairing from contacting the water.  So how would it be positioned so accurately for the landing and given anything but calm seas it would have to deploy moments before splash down.

That's why I thought deploying from on board the fairing makes sense.
Title: Re: Fairing reuse
Post by: rsdavis9 on 07/14/2017 12:13 pm


There seemed to be people with information who suggested it was carried with the fairing. I can't recall the source, though. A case could be made for either option.

I think it was a comment from Gwynn. She said something that could be interpreted either way.

To me what makes the most sense is to use guidance and steerable chutes which BTW can be low weight and have a chase ship with the bouncy castle on it and guide the ship for the catch at the landing.
Title: Re: Fairing reuse
Post by: Kabloona on 07/14/2017 09:55 pm
To me what makes the most sense is to use guidance and steerable chutes which BTW can be low weight and have a chase ship with the bouncy castle on it and guide the ship for the catch at the landing.

Yes, because if the fairing carries its own bouncy castle, there's no need for high accuracy in the chute steering (because it wouldn't need to hit a fixed target), which seems to be the long pole in the tent at the moment.

And having the ship carry the bouncy castle means the castle can be quite large/heavy, which isn't the case if the fairing is carrying it.
Title: Re: Fairing reuse
Post by: Space OurSoul on 07/15/2017 12:00 am
I think Elon's use of the term "bouncy castle" implies that the castle will be on the ocean in some form. If it were to be carried with the fairing, he would have used something like "air bags" or whatever the term was for spirit+opportunity's landing balloons.
Title: Re: Fairing reuse
Post by: HMXHMX on 07/16/2017 01:47 am
I think Elon's use of the term "bouncy castle" implies that the castle will be on the ocean in some form. If it were to be carried with the fairing, he would have used something like "air bags" or whatever the term was for spirit+opportunity's landing balloons.


I'd like to remind everyone that Bob Truax was planning to use inflated mats on a barge to recover one of his sea-launched rockets.  I believe it was the Excalibur version, sometime in the late 1980s. So the idea isn't new to SpaceX.
Title: Re: Fairing reuse
Post by: savuporo on 07/16/2017 02:07 am
A steerable chute system requires guidance, positioning and a lot of control authority. This is all a lot of mass...

From an (old) description of DragonFly JPADS-10K system. Note lead acid batteries ... Fairing halves would probably require JPADS-30K equivalent.

Quote
The Dragonfly is one of the two 10Klb-capable systems developed by the US Army NSC JPADS ACTD. The
Dragonfly team is a collaborative effort between Para-Flite Inc., developer of the decelerator system, Wamore Inc.
as the developer of the AGU, Robotek Engineering, providing the avionics suite, and Charles Stark Draper
Laboratory leading the GN&C software development. The program began in fiscal year 2003 and fully integrated
system flight tests commenced in the first quarter of fiscal year 2004....

The AGU connects to the parafoil risers and is suspended between the parafoil and the payload. The AGU
currently weights approximately 175-lb. The design has proven extremely rugged and robust through flight test. As with the parafoil design, great attention has been paid to minimization of unit cost. The AGU and its avionics suite rely heavily on the effective integration of commercial-off-the-shelf components. Primary system electromechanical subcomponents include: a pair of 1.5 hp brushed servomotors, motor controller, 68:1 gear reducers, 900Mhz RF modem (as test equipment), microprocessor, dual-channel GPS, and three 12VDC sealed lead acid batteries. Two batteries provide 24VDC to the actuators, while the third battery provides power to the avionics.

Source:
NPS.edu pdf (http://faculty.nps.edu/oayakime/ADSC/PATCAD%20-%20Benney%20-%20The%20New%20Military%20Applications%20of%20Precision%20Airdrop%20Systems.pdf)

EDIT: add DragonFly spec .. which is just one of a few operational JPADS systems
http://airborne-sys.com/product/dragonfly-army-cargo-delivery-parachute/

Title: Re: Fairing reuse
Post by: john smith 19 on 08/29/2017 06:40 pm
I'd like to remind everyone that Bob Truax was planning to use inflated mats on a barge to recover one of his sea-launched rockets.  I believe it was the Excalibur version, sometime in the late 1980s. So the idea isn't new to SpaceX.
A good reminder that there are very few new ideas in this field, although wheather or not SX knew of that when Musk mentioned it is another matter.   :(

It's impressive how small the control package on a modern parafoil can be to (150lb to control a load of 10 000 lb)

In hindsight fairing reuse is one of those ideas that's an obvious way to lower reuse costs, but has not been attended to because of the bigger payoffs of (say) upper stage reuse, despite their exponentially more difficult complexity.

It's been quite astonishing to me how fast this process has come together once the decision was made to pursue it.

That said I'm not sure it would have been possible without the "enabling technology" of a recovery barge on station to land the first stage on.

Title: Re: Fairing reuse
Post by: faramund on 08/29/2017 09:55 pm
Does anyone know of any updates from the last two launches? Its all gone quiet, which could be taken as somewhat worrying.
Title: Re: Fairing reuse
Post by: CuddlyRocket on 08/30/2017 02:46 am
Does anyone know of any updates from the last two launches? Its all gone quiet, which could be taken as somewhat worrying.

Alternatively, they're quite close to - or at least can see a path to - success and don't want to give competitors any insight into what the problems and potential solutions are. After all, you can implement fairing recovery even on an expendable booster. (I note that the recovery vessel for the last flight has winching gear and a large canvas tent on deck, hinting they have something they want hidden.)
Title: Re: Fairing reuse
Post by: old_sellsword on 08/30/2017 03:34 am
...(I note that the recovery vessel for the last flight has winching gear and a large canvas tent on deck, hinting they have something they want hidden.)

If you're referencing the large white tent and A-frame on the back of NRC Quest, those have nothing to do with fairing recovery. They're for working on recently recovered Dragons before they get back to port.
Title: Re: Fairing reuse
Post by: john smith 19 on 08/30/2017 06:22 am
Does anyone know of any updates from the last two launches? Its all gone quiet, which could be taken as somewhat worrying.

Alternatively, they're quite close to - or at least can see a path to - success and don't want to give competitors any insight into what the problems and potential solutions are. After all, you can implement fairing recovery even on an expendable booster. (I note that the recovery vessel for the last flight has winching gear and a large canvas tent on deck, hinting they have something they want hidden.)
Thinking about it not really. Fairing sep occurs so far down range you need a ship (maybe a plane) out there already to collect it.

But you won't have one out there unless you've got something else (like a stage) to recover already.

So having the infrastructure in place to do stage recovery may be the only way to afford to do cost effective fairing recovery.

At a minimum of $5m a pop a few reuses could lop a significant (for SX)  chunk off their bottom line costs.
Title: Re: Fairing reuse
Post by: kaiser on 09/08/2017 04:18 pm
Does anyone know of any updates from the last two launches? Its all gone quiet, which could be taken as somewhat worrying.

Alternatively, they're quite close to - or at least can see a path to - success and don't want to give competitors any insight into what the problems and potential solutions are. After all, you can implement fairing recovery even on an expendable booster. (I note that the recovery vessel for the last flight has winching gear and a large canvas tent on deck, hinting they have something they want hidden.)
Thinking about it not really. Fairing sep occurs so far down range you need a ship (maybe a plane) out there already to collect it.

But you won't have one out there unless you've got something else (like a stage) to recover already.

So having the infrastructure in place to do stage recovery may be the only way to afford to do cost effective fairing recovery.

At a minimum of $5m a pop a few reuses could lop a significant (for SX)  chunk off their bottom line costs.

I wouldn't say that it's only financially viable if you already have a ship in the area.  A decent sized ship might cost you $15k/day and you'd need to use a lot of days before you even start to make a dent in the $5M worth of hardware that the boat just caught.
Title: Re: Fairing reuse
Post by: john smith 19 on 09/09/2017 07:38 pm
Quote from: john smith 19
Thinking about it not really. Fairing sep occurs so far down range you need a ship (maybe a plane) out there already to collect it.

But you won't have one out there unless you've got something else (like a stage) to recover already.

So having the infrastructure in place to do stage recovery may be the only way to afford to do cost effective fairing recovery.

At a minimum of $5m a pop a few reuses could lop a significant (for SX)  chunk off their bottom line costs.

I wouldn't say that it's only financially viable if you already have a ship in the area.  A decent sized ship might cost you $15k/day and you'd need to use a lot of days before you even start to make a dent in the $5M worth of hardware that the boat just caught.
The money does mount up. A 10 day voyage (3 day out, 3 day back, 4 days on site for scrubs) is $150K, before refurb and reassembly costs). As always launching at the first opportunity is better.
It's a fair point, but you've got to have a company that's motivated to want to save those bottom line costs to begin with.
AFAIK fairing recovery could have been attempted by any LV mfg since the late 1960's, if they cared enough about launch costs to do so.  :(
Title: Re: Fairing reuse
Post by: wannamoonbase on 10/13/2017 04:53 pm
Bump

We've had a few missions lately and a bold statement from Gwen on fairing reuse next year.

Any new information on development or experimental recovery?
Title: Re: Fairing reuse
Post by: Azular on 10/14/2017 03:23 am
At the ISS Research & Development Conference 2017 on July 19 during 'An Innovation Discussion with Elon Musk'

Elon Musk ... "I think weve got a decent shot of recovering the fairing by the end of the year and possibily reflight by either late this year or early next"

https://www.youtube.com/watch?v=kz1nOQ40xI4&t=7m26s

 :)

Edit: Okay, time marker didn't seem to work, look at about 7:26 into the recording
Title: Re: Fairing reuse
Post by: SmallKing on 10/15/2017 04:43 am
Recovered a piece of fairing
https://www.flickr.com/photos/29418863@N04/sets/72157686191312452
Title: Re: Fairing reuse
Post by: ChrisC on 10/31/2017 02:22 am
During the KoreaSat countdown coverage, the host started to say that the "fairing boat" was in position for recovery, but corrected himself to refer to the "drone ship".

Nonetheless, one hopes to see something from SpaceX or Elon, because this could be the last fairing mission for a while.  I suppose we can expect that Zuma has a fairing, but considering the secrecy, maybe they wouldn't let us see any fairing recovery news from that mission.  Then we have a Dragon mission (no fairing), then Iridium (west coast: fairing recovery?), then finally back to Canaveral for Hispasat and a fairing mission.
Title: Re: Fairing reuse
Post by: hamerad on 11/03/2017 07:13 am
hmm intact fairing possibly?

 Boring Sled‏
@BoringSled
Follow Follow @BoringSled
More
I'M MR STEVEN LOOK AT ME AND I GOT MY FAIRING!


https://twitter.com/BoringSled/status/925826712511815680

Edit:Photo removed due to copyright reasons
Title: Re: Fairing reuse
Post by: woods170 on 11/03/2017 11:15 am
hmm intact fairing possibly?

 Boring Sled‏
@BoringSled
Follow Follow @BoringSled
More
I'M MR STEVEN LOOK AT ME AND I GOT MY FAIRING!


https://twitter.com/BoringSled/status/925826712511815680

Edit:Photo removed due to copyright reasons
It might be a fairing, but whatever it is, it is wrapped in something by the looks of it.
Title: Re: Fairing reuse
Post by: vanoord on 11/03/2017 03:10 pm
Sure looks like one. Is the size correct for a full fairing?

Going off the (likely) size of the RIB next to it, yes.

Whether or not it's a complete fairing is another question.
Title: Re: Fairing reuse
Post by: Lar on 12/14/2017 07:10 pm
Wonder what a "short term opportunity area" means...

If I remember correctly, someone up-thread said this would be used for storing previously flown Falcon 9 boosters.
I think you're thinking of the 35000 s.f. of land and 77000 s.f. of water that are being added to SpaceX's permit near berths 51 and 52. In any case, we will see later this month what happens to the B1036 booster with the Iridium NEXT-4 flight.

Quote
Backqround: On January 7,2016, the Board approved RP 15-19 to SpaceX for the use
of 35,000 s.f. of land and 77,000 s.f. of water at Berths 51 and 52 along Miner Street in
San Pedro. RP 15-19 allowed for: berthing rights for the Marmac landing barge and
auxiliary vessels; construction of landside improvements including the installation of
rocket support pedestals on a concrete pad; and installation of temporary perimeter
fencing, an office trailer, a guard shack and portable restrooms. SpaceX's premises are
utilized to berth vessels that recover expended rockets and capsules from over 100
miles offshore and return the respective equipment for land based transportation to
various locations.
ln response to the Board's concern regarding insurance limits and coverage under selfinsurance,
the First Amendment to RP 15-19 increased insurance requirements to
provide superior insurance coverage, thereby reducing the Harbor Department's
financial risk exposure arising from SpaceX's operations.
The Second Amendment to RP 15-19 increased permit premises primarily at Berth 53
and adjusted compensation correspondingly. The additional areas provided SpaceX
with access to a wider area such that it can conduct its operations more safely and
efficiently, and also reduce the length of time that Miner Street is shut down, thereby
lessening the impact of SpaceX operations on neighboring tenants. A provision was
also added to allow the Harbor Department to be reimbursed for expenses incurred as a
result of the Tenant's operations such as Port Police fees (escort, street closures, etc.);
Construction & Maintenance costs (placement of k-rails, plumbing and electrical
services, etc.); Engineering fees (inspection fees, etc.); rental fees for use of additional
areas (staging for media, parking, etc.); and other related. costs.
SpaceX has conducted five rocket and capsule recoveries since 2016. On November
15, 2017, SpaceX submitted an application for additional premises in order to
accommodate the MA/ Mr. Steven, a 205-foot long vessel dedicated to recovering the
fairing portion of rockets which protect the spacecraft and reduce drag during flight.
No additional hazardous materials will be brought to the Port. The extended area will
allow a better layout for its operations and allow SpaceX to remove equipment on top of
their sea vans as much as possible, and better contain their equipment behind the
perimeter fencing, away from public view.
The proposed Third Amendment (Transmittal 1) to RP 15-19 modifies the permit
premises by adding a9,143 s.f. land parcel and a 25,500 s.f. submerged land parcel on
the south side of its current premises (Transmittal2), and modifying the compensation
accordingly, from $24,328.73 to $28,095.82 a month. ln anticipation of the vessel's
arrival in mid to late December 2018, SpaceX would like to take possession of the
additional premises by December 15, 2017.
Source: https://www.portoflosangeles.org/Board/2017/December%202017/121417_Regular_Agenda_Item_8.pdf
I think it interesting that Mr. Steven might migrate coasts.
Title: Re: Fairing reuse
Post by: RedLineTrain on 12/17/2017 01:15 am
I think it interesting that Mr. Steven might migrate coasts.

As far as I know, it has already...

Marine Traffic link (http://www.marinetraffic.com/en/ais/details/ships/shipid:3439091/mmsi:338358000/imo:9744465/vessel:MR_STEVEN)
Title: Re: Fairing reuse
Post by: Bob Shaw on 12/17/2017 01:27 am
Google 'Killer Tomato Target' and choose images - I think I took some of them. The predeployment package is *very* small and probably weighs less than 20Kg.

This might serve as a ballute and a flotation device.
Title: Re: Fairing reuse
Post by: Lar on 12/17/2017 01:48 am
I think it interesting that Mr. Steven might migrate coasts.

As far as I know, it has already...

Marine Traffic link (http://www.marinetraffic.com/en/ais/details/ships/shipid:3439091/mmsi:338358000/imo:9744465/vessel:MR_STEVEN)
That wasn't my point, rather that at this time they sent Mr. Steven rather than hiring another vessel. That suggests that Mr. Steven has some gear on board that it would be cost ineffective to duplicate,  or ship it all to the other coast and place on a similar vessel...  And THAT suggests that maybe there were some vessel mods (just like an ASDS got some mods) and further that they're not completely sure they have it all right yet to the point of duplicating it all. 

To me this all makes sense and probably was predictable without the move confirmation, but the move confirmation is just that, a bit of corroboration for the above.

Note that except for canal delay and transit times[1], Mr. Steven is much faster[2] than a towed ASDS but as launch cadence increases they can't sent it back and forth every time... once they have this figured out I would expect them to duplicate the setup, as they did for the ASDS.

1 - assuming they didn't go round the horn, which adds a LOT, what does Marine Traffic suggest?
2 - about 3x or better, 25 kt vs 8 kt I think?
Title: Re: Fairing reuse
Post by: Lar on 12/17/2017 01:53 am
PS, what is the long term history of Mr. Steven? Based on some stuff posted here and on the FB group about her owners, charter offers, etc, I got the impression, perhaps false, that long term she was an Atlantic vessel, not a Pacific one, so this might be a temporary move rather than a permanent one (that is, which coast ends up with her, vs which coast gets the "new set" of equipment and another vessel?)
Title: Re: Fairing reuse
Post by: vanoord on 12/18/2017 08:21 am
My suspicion with Mr.Steven is that its speed* is the reason they've chartered it.

Either to get to the fairing before it sinks (but flotation bags would probably negate that) or to get under the fairing as it descends and provide a landing platform for it.

Looks like she was built as a crew transfer vessel for Gulf oil platforms but obviously can be used elsewhere for other purposes.


* Capable of 32 knots, if I got it right last time I looked it up.
Title: Re: Fairing reuse
Post by: Lar on 12/18/2017 12:21 pm
There are other fast boats. My inferences are around how close to "done" they are with equipment development... ie, not that done yet or they would duplicate instead of sending her through the canal.
Title: Re: Fairing reuse
Post by: zack on 12/19/2017 02:27 pm
Looks like Mr. Steven is getting the "Bouncy Castle" upgrade in LA, maybe we get to see it in use on Iridium.

https://imgur.com/gallery/MQcEE (https://imgur.com/gallery/MQcEE)

credit due to u/vshie on reddit.
https://www.reddit.com/r/spacex/comments/7ktq9y/new_space_x_mystery_boat_with_odd_gearin_port_of/ (https://www.reddit.com/r/spacex/comments/7ktq9y/new_space_x_mystery_boat_with_odd_gearin_port_of/)
Title: Re: Fairing reuse
Post by: cscott on 12/19/2017 02:31 pm
Looks like Mr. Steven is getting the "Bouncy Castle" upgrade in LA, maybe we get to see it in use on Iridium.

https://imgur.com/gallery/MQcEE (https://imgur.com/gallery/MQcEE)

credit due to u/vshie on reddit.
https://www.reddit.com/r/spacex/comments/7ktq9y/new_space_x_mystery_boat_with_odd_gearin_port_of/ (https://www.reddit.com/r/spacex/comments/7ktq9y/new_space_x_mystery_boat_with_odd_gearin_port_of/)
Wow!  There's a rumor that Iridium is going to forego legs and be dumped in the ocean -- but perhaps they'll use the margin for a fairing recovery test?
Title: Re: Fairing reuse
Post by: ugordan on 12/19/2017 02:36 pm
There's a rumor that Iridium is going to forego legs and be dumped in the ocean -- but perhaps they'll use the margin for a fairing recovery test?

I think you might be underestimating the margin they have on Iridium flights even with S1 recovery hardware included. If their margin was so razor-thin that fairing recovery is a make or break thing, they would not have attempted booster recovery on prior launches at all. Simply a slightly higher reentry energy would fix the mass overhead of fairing recovery hardware, something that would still be vastly easier on the hardware than a typical GTO launch.
Title: Re: Fairing reuse
Post by: TrueBlueWitt on 12/19/2017 02:39 pm
Looks like Mr. Steven is getting the "Bouncy Castle" upgrade in LA, maybe we get to see it in use on Iridium.

https://imgur.com/gallery/MQcEE (https://imgur.com/gallery/MQcEE)

credit due to u/vshie on reddit.
https://www.reddit.com/r/spacex/comments/7ktq9y/new_space_x_mystery_boat_with_odd_gearin_port_of/ (https://www.reddit.com/r/spacex/comments/7ktq9y/new_space_x_mystery_boat_with_odd_gearin_port_of/)
Wow!  There's a rumor that Iridium is going to forego legs and be dumped in the ocean -- but perhaps they'll use the margin for a fairing recovery test?

Mr Steven's new nickname should be "Dock Ock"!
Title: Re: Fairing reuse
Post by: cscott on 12/19/2017 02:44 pm
There's a rumor that Iridium is going to forego legs and be dumped in the ocean -- but perhaps they'll use the margin for a fairing recovery test?

I think you might be underestimating the margin they have on Iridium flights even with S1 recovery hardware included. If their margin was so razor-thin that fairing recovery is a make or break thing, they would not have attempted booster recovery on prior launches at all. Simply a slightly higher reentry energy would fix the mass overhead of fairing recovery hardware, something that would still be vastly easier on the hardware than a typical GTO launch.
I have no particular knowledge of margins other than you ought to be able to trade leg mass with recovery hardware mass almost 1-1.  (Not quite, but the fairing is jettisoned 40s into the 6m34s S2 burn.)
Title: Re: Fairing reuse
Post by: Coastal Ron on 12/19/2017 02:54 pm
Looks like Mr. Steven is getting the "Bouncy Castle" upgrade in LA, maybe we get to see it in use on Iridium.

https://imgur.com/gallery/MQcEE (https://imgur.com/gallery/MQcEE)

credit due to u/vshie on reddit.
https://www.reddit.com/r/spacex/comments/7ktq9y/new_space_x_mystery_boat_with_odd_gearin_port_of/ (https://www.reddit.com/r/spacex/comments/7ktq9y/new_space_x_mystery_boat_with_odd_gearin_port_of/)
Wow!  There's a rumor that Iridium is going to forego legs and be dumped in the ocean -- but perhaps they'll use the margin for a fairing recovery test?

Mr Steven's new nickname should be "Dock Ock"!

Increasing what SpaceX is doing is hilarious in it's audacity - truly straight out of comic books! Brilliant!
Title: Re: Fairing reuse
Post by: DavidH on 12/19/2017 03:07 pm
Looks like Mr. Steven is getting the "Bouncy Castle" upgrade in LA, maybe we get to see it in use on Iridium.

https://imgur.com/gallery/MQcEE (https://imgur.com/gallery/MQcEE)

credit due to u/vshie on reddit.
https://www.reddit.com/r/spacex/comments/7ktq9y/new_space_x_mystery_boat_with_odd_gearin_port_of/ (https://www.reddit.com/r/spacex/comments/7ktq9y/new_space_x_mystery_boat_with_odd_gearin_port_of/)
Wow. Looks like Mr. Steven's Special Equipment (http://www.seatranmarine.com/vessels-1/mr-steven) list is out of date.
That's just awesome!
Another vote for Dock Ock.
Title: Re: Fairing reuse
Post by: jebbo on 12/19/2017 03:20 pm
Hmm ... not sure how this is meant to work. Presumably the fairing returns in two halves. Does the ship catch one, then sprint to catch the other? Or have I missed something obvious?

--- Tony
Title: Re: Fairing reuse
Post by: JBF on 12/19/2017 03:41 pm
Hmm ... not sure how this is meant to work. Presumably the fairing returns in two halves. Does the ship catch one, then sprint to catch the other? Or have I missed something obvious?

--- Tony

Probably just experimenting with one and once it works they will deploy 2 ships.
Title: Re: Fairing reuse
Post by: jebbo on 12/19/2017 03:56 pm
Probably just experimenting with one and once it works they will deploy 2 ships.

Possibly.

If I was designing it, I'd go for different chutes on the two halves so one descends slower, and possibly active shrouds so you can be sure they land close to each other.  Then the catch one, sprint, catch the other works. But I have no idea how feasible that is ...

--- Tony
Title: Re: Fairing reuse
Post by: Lar on 12/19/2017 04:08 pm
If they need two ships each coast (because each can only catch one half), the might have to go with a different supplier. SeaTran has an impressive list of vessels:

http://www.seatranmarine.com/vessels_sp.html#

.... But most of them are only 1/2 the horsepower or less, and therefore somewhat slower. Mr. Steven is the only 10000 hp class vessel.

However, maybe they ultimately can get by with 4-5 knots less top speed?

I think it's possible both halves get caught in one net/Castle (or they have a way to use two castles on top of each other or something? don't know what equipment is in the arms....
Title: Re: Fairing reuse
Post by: dgates on 12/19/2017 04:23 pm
Well, we know that from liftoff to booster touchdown is on the order of ten minutes, give or take.  I wonder what the typical timeline might be from launch to fairing touchdown / capture might be?  30 minutes perhaps?  What do ya’ll think?
Title: Re: Fairing reuse
Post by: russianhalo117 on 12/19/2017 05:20 pm
If the fairings employ a VHAVHO (Very High Altitude with Very High Opening) or HAHO (High Altitude with High Opening) deployment sequence compared to HALO deployment sequence then precise GPS guided range and targeting becomes possible.
Title: Re: Fairing reuse
Post by: Coastal Ron on 12/19/2017 05:33 pm
Any speculation on what direction the fairing would be approaching the quad-arm web-catcher?

- Not from the bow (obviously).

- If it was from the stern then you'd think they would be trying to catch the fairing while the boat was in motion. If so they that implies communications between the boat and the parachute system so that they can be cooperative in the landing.

- If the fairing is meant to approach from the sides then that would imply that the ship would not be moving, so it would be like an ASDS minus the station keeping ability.

Also, is Mr. Steven likely to be manned during a catch attempt?

Edit: Corrected name of Mr. Steven
Title: Re: Fairing reuse
Post by: RonM on 12/19/2017 05:40 pm
Any speculation on what direction the fairing would be approaching the quad-arm web-catcher?

- Not from the bow (obviously).

- If it was from the stern then you'd think they would be trying to catch the fairing while the boat was in motion. If so they that implies communications between the boat and the parachute system so that they can be cooperative in the landing.

- If the fairing is meant to approach from the sides then that would imply that the ship would not be moving, so it would be like an ASDS minus the station keeping ability.

Also, is Mr. Stevens likely to be manned during a catch attempt?

From the stern so Mr. Stevens can match the forward speed of the fairing. As long as the parachute system can maintain a steady course there is no need for communication with the boat. Use the maneuverability of Mr. Stevens to gently catch the fairing.
Title: Re: Fairing reuse
Post by: Lar on 12/19/2017 05:41 pm
Mr Steven. SINGULAR

Their naming convention uses first names. EIther Mr. Ed or Lady Edwina depending on the names.

As for direction I suspect Mr Steven would head into the wind, ahead of the fairing, which would approach from behind.  (flying into the wind means the lowest groundspeed for the fairing) Up/down throttle could be used to finesse any altitude overage or shortfall.
Title: Re: Fairing reuse
Post by: LouScheffer on 12/19/2017 05:49 pm
I think it's possible both halves get caught in one net/Castle (or they have a way to use two castles on top of each other or something? don't know what equipment is in the arms....
If they put a net across the four arms, then a strong line down the diagonal would divide the net into two parts.  Each could then catch a fairing half without them contacting each other.
Title: Re: Fairing reuse
Post by: leetdan on 12/19/2017 05:57 pm
Remember this idea is at least two years old at this point, and they've had nearly-intact fairings recovered going back 8 months.  The flight profile should be well established at this point.

I don't think the composite fairing would be a risk to crew inside the metal superstructure of the boat, but the running gear would certainly be at risk if they're way off.  Keep in mind the net is quite a bit bigger than the fairing.
Title: Re: Fairing reuse
Post by: cscott on 12/19/2017 06:36 pm
Remember Mr. Steven switched coasts to participate in this.  Could be that the Go sisters weren't thrilled about catching a falling fairing (didn't want to have doc ock arms attached, didn't have adequate protection for the bridge, couldn't go fast enough, who knows) and Mr. Steven was the only one they could find who was enthusiastic about (the risk involved in) trying a new thing.

I agree with the posters who think this is likely the setup for a single fairing half for now, and they'd expand it to two (whether that's two in one net or two ships or whatever) only once they have a solid success with single recovery.  It's cheaper to iterate and try new things if you don't have to maintain parallel copies.
Title: Re: Fairing reuse
Post by: bstrong on 12/19/2017 07:11 pm
If they need two ships each coast (because each can only catch one half), the might have to go with a different supplier. SeaTran has an impressive list of vessels:
<snip>

Mr. Steven now has a GO (Guice Offshore) logo in the latest images. So, it looks like Guice may be acquiring vessels to SpaceX's specs?
Title: Re: Fairing reuse
Post by: Lar on 12/19/2017 07:28 pm
Mr. Steven and the GO Twins are stablemates now? Or maybe SeaTran leased it to them for a bit?
Title: Re: Fairing reuse
Post by: freddo411 on 12/19/2017 07:39 pm
Speculation:

Fairing glides in from the stern, lands in a net slightly elevated toward the bow.   Immediately the crew lowers the ropes supporting the bow end of the net, changing the incline toward the bow.   Fairing is slid onto the bow end of the deck, out of the net. (maybe a cushion is setup there already?).

Now the net is reset to catch the second fairing.
Title: Re: Fairing reuse
Post by: Lar on 12/19/2017 07:53 pm
Speculation:

Fairing glides in from the stern, lands in a net slightly elevated toward the bow.   Immediately the crew lowers the ropes supporting the bow end of the net, changing the incline toward the bow.   Fairing is slid onto the bow end of the deck, out of the net. (maybe a cushion is setup there already?).

Now the net is reset to catch the second fairing.

Quite! ... with enough tensioning lines (if we assume net, which just doesn't square with Bouncy Castle but ok) it should be possible to set up a "wave" that pushes the fairing right off, just  like a surfboard riding a wave... If there is a minute of spacing between the two halves, that would be plenty.
Title: Re: Fairing reuse
Post by: Pasander on 12/19/2017 08:35 pm
If there is a minute of spacing between the two halves, that would be plenty.

If they can open at different altitudes and/or have a different size of parachutes, and can control the glide profile..  I don't see why even 15 minutes of separation in landing times wouldn't be possible. (Full disclosure: I skydived when I was young and immortal.)
Title: Re: Fairing reuse
Post by: Lar on 12/19/2017 09:16 pm
I would think they'd want the equipment to be similar between halves for cost reasons, but all the rest would be variable.
Title: Re: Fairing reuse
Post by: RocketLover0119 on 12/20/2017 01:23 am
This is exactly what my speculation is... If this is going to be the method I pray they webcast it

Speculation:

Fairing glides in from the stern, lands in a net slightly elevated toward the bow.   Immediately the crew lowers the ropes supporting the bow end of the net, changing the incline toward the bow.   Fairing is slid onto the bow end of the deck, out of the net. (maybe a cushion is setup there already?).

Now the net is reset to catch the second fairing.
Title: Re: Fairing reuse
Post by: cscott on 12/20/2017 01:31 am
I still think they'll catch a single fairing in the net before they try to catch two.
Title: Re: Fairing reuse
Post by: jjyach on 12/20/2017 01:39 am
As far as I am aware, all retrieval attempts so far have been for one half, the active half I believe.
Title: Re: Fairing reuse
Post by: cppetrie on 12/20/2017 01:49 am
My guess is that this launch will be the first legitimate effort to catch the fairing on the fly and keep it from getting wet. My understanding is that the previous attempts have all been controlled descents but still splashing in the water. No catches yet. This looks to me like the first catch attempt and as such will involve only a single fairing half. In addition to giving them an idea of how well the catch idea is going to work it’ll also give them a sense of the margin for catching two with a single vessel. It is possible they’ll try to control both halves on the way down as part of understanding the timing of catching two. I’m just not convinced they’ll actually try to catch both.
Title: Re: Fairing reuse
Post by: QuantumG on 12/20/2017 01:52 am
https://twitter.com/Teslarati/status/943300377570508800

For real?
Title: Re: Fairing reuse
Post by: IanThePineapple on 12/20/2017 01:56 am
The claws have hooks on the top of each, just pointing it out.
Title: Re: Fairing reuse
Post by: meekGee on 12/20/2017 01:57 am
Irrespective of the picture, just a data point, when the military uses net-captured drones, the drone basically fly into a net that is pretty steep - they don't land on a horizontal net.

Many differences between the two systems of course.
Title: Re: Fairing reuse
Post by: meekGee on 12/20/2017 02:00 am
My speculation:

The parachute system overtakes the boat, doing a fly-by maybe 10-20' overhead.

The precision act made by the parachute system is a timely release of the fairing to hit the net.

Seems easier to control timing then to control several flight parameters simultaneously.

The parachute system can trade speed for lift during the final flare, and the computer just needs to calculate a "dropping solution".

Also this way, parachute entanglement is pre-solved.

And yes, one ship per half-fairing, and only a single recovery this flight.
Title: Re: Fairing reuse
Post by: deruch on 12/20/2017 02:11 am
Fairing halves are very large, unwieldy, and heavy-ish equipment that I don't imagine would be easy to manhandle while on a moving ship at sea.  And also possibly at an elevated speed.  So, either this set up is capable of catching 2 halves without much deckhand intervention or there will eventually have to be 2 ships for any launch where SpaceX tries to catch both halves.  I have trouble imagining that they are ever going to try catching and unloading the first half like an F1 pit crew while still having enough time to reset the catching mechanism and pre-positioning the ship for the second run.  Even if the parachutes are capable of creating a few minutes of difference in landing time that's a lot to ask. 
Title: Re: Fairing reuse
Post by: garcianc on 12/20/2017 03:28 am
Ok, super crazy idea (perhaps wine-induced), so bear with me.

How feasible would it be to tether the fairing mid-flight to the boat and parasail the thing down to the cradle/claw basket by winching it down in a controlled fashion? Once tethered, the boat's speed could be used to raise altitude or keep the fairing from falling too fast until it is caught.

Presumably, all the equipment the fairing would need would be a [right type of] parachute system and a long enough tether to hang down so the boat can catch the tether before the fairing hits the water.

It sounds James Bond enough for SpaceX  ;D
Title: Re: Fairing reuse
Post by: wannamoonbase on 12/20/2017 03:48 am
I think 1 ship per half. 

1 ship for both could work sometimes, but maybe not every time.

Very interesting concept, not what I was imaging.  I was thinking a catamaran with a net between the sides.
Title: Re: Fairing reuse
Post by: JamesH65 on 12/20/2017 10:16 am
Could just use one ship, catch the first, lower the net a bit, pull another net over the top of it. Would be quick and easy, and simply automated.
Title: Re: Fairing reuse
Post by: Comga on 12/20/2017 12:56 pm
Those arms look solidly fixed to me. 
No hydraulically actuated elbows
Don’t look like pivoting bases
Hard to envision how they would attach winches to those fixed eyelets
Certainly no features for the fancier schemes described above
Don't see how they will get the fairing half out if the net other than to cruise home and use a crane
How would they even cover a fairing in a high, fixed net?

What’s the opposite of “Rube Goldberg” for excessive simplicity?
Title: Re: Fairing reuse
Post by: cscott on 12/20/2017 01:05 pm


What’s the opposite of “Rube Goldberg” for excessive simplicity?

KISS?
Title: Re: Fairing reuse
Post by: ugordan on 12/20/2017 01:17 pm
It's pretty clear to me that the reason is to buy mass for the fairing recovery experiment, but @IridiumBoss isn't allowed to say that (or is just being polite by not spoiling SpaceX's announcement).  That explains his coy answers.

If it's pretty clear to you, perhaps you'd like to share your reasoning with the rest of us as that's the 2nd time you state this, in the updates thread nonetheless.

For example, your reasoning on why this fairing recovery experiment requires so much extra weight offload from S1 that SpaceX would have to go all the way from a rapid flip and boostback burn + reentry burn which they executed on the previous Iridium flight, to not only skipping at least a GTO-type reentry with no boostback burn, but going all the way and completely giving up on recovery altogether. Fact is the reentry energy trade space between these two reentry profiles alone is almost *guaranteed* to vastly outweigh any additional fairing recovery mass they might put on the vehicle. Or, for all we know, might have already *been* flying that same extra mass for several past flights.

I said it before and I'll say it again, I think you're vastly underestimating the performance reserve SpaceX have for this flight and the leeway in the recovery method they therefore could choose if the reserve is deemed insufficient for the recovery method using a boostback burn.

The answer given by Chris_G and others, that they're simply getting rid of block 3 hardware is a much more plausible answer.
Title: Re: Fairing reuse
Post by: Jet Black on 12/20/2017 01:32 pm
https://twitter.com/Teslarati/status/943300377570508800

For real?

MSV Don't Try This At Home.
Title: Re: Fairing reuse
Post by: IanThePineapple on 12/20/2017 01:34 pm
Irrespective of the picture, just a data point, when the military uses net-captured drones, the drone basically fly into a net that is pretty steep - they don't land on a horizontal net.

Many differences between the two systems of course.

Yeah, the fairing would essentially need to stall just before the net in order to land on a horizontal net without sliding right off.
Title: Re: Fairing reuse
Post by: meekGee on 12/20/2017 01:38 pm
Irrespective of the picture, just a data point, when the military uses net-captured drones, the drone basically fly into a net that is pretty steep - they don't land on a horizontal net.

Many differences between the two systems of course.

Yeah, the fairing would essentially need to stall just before the net in order to land on a horizontal net without sliding right off.
Hence the "cut loose" idea.

Even a 15' drop would add enough vertical velocity so the line of flight is near 45 degrees.

A 30' (10 m) drop might be better.

The wind won't have enough time to ruin the targeting - about 1 second in free fall.
Title: Re: Fairing reuse
Post by: scdavis on 12/20/2017 02:22 pm
I have trouble imagining that they are ever going to try catching and unloading the first half like an F1 pit crew while still having enough time to reset the catching mechanism and pre-positioning the ship for the second run.

I agree with you about the difficulty of quickly unloading all the way to the deck. But -- those arms are quite high. They might be able to simply lower the first net almost to the deck (fully automatic, nothing fancy, just lower the net straight down). Then attach another net *on top* and bring it tight. If the lines are taut enough, it could conceivable catch the second fairing without the second faring sagging down to touch the first fairing.

If this is confusing, just picture a double-decker net with a fairing in each net as the configuration after they have been caught.

Tricky bit will be for the crew to quickly attach the second net after the first fairing has been caught. Otherwise, nothing fancy required.
Title: Re: Fairing reuse
Post by: AncientU on 12/20/2017 02:43 pm
Could be wide enough to have separate halves, left and right. 
A ridge in the middle could keep the pair of landings separate and enable either fairing half to be recovered first.
Title: Re: Fairing reuse
Post by: cscott on 12/20/2017 03:04 pm
It's pretty clear to me that the reason is to buy mass for the fairing recovery experiment, but @IridiumBoss isn't allowed to say that (or is just being polite by not spoiling SpaceX's announcement).  That explains his coy answers.

I said it before and I'll say it again, I think you're vastly underestimating the performance reserve SpaceX have for this flight and the leeway in the recovery method they therefore could choose if the reserve is deemed insufficient for the recovery method using a boostback burn.

Perhaps.  There is L2 info re: the re-entry profile, maybe we'll discuss that further there.  My post was stating a cause-and-effect: @IridiumBoss' coy response, which seems to hint at the key factor being something he can't directly disclose, was making me more certain. I should have written "It's becoming more clear to me" instead of just "It's pretty clear to me" to make the point clearer. As you mention, the actual reasoning is in other posts, I didn't feel I had to repeat that.

And I'm not claiming the fairing experiment is the *only* factor.  Just that it's one piece which, combined with the other issues discussed here (block 3, lack of space, etc), may have pushed the decision over the edge into expendibility.
Title: Re: Fairing reuse
Post by: Stefan.Christoff.19 on 12/20/2017 03:48 pm
There might be a very obvious answer to this question but since it's not obvious to me I'll ask it.
      Why can't the two halves be caught in the same net despite contact. Would the damage be that great that would render the effort worthless? I don't know enough about the material and speed of landing to be able to discern the impact.
     Also seems to me that the first try is more about catching than using the fairings that were caught.
Title: Re: Fairing reuse
Post by: geoffc on 12/20/2017 04:39 pm

- If it was from the stern then you'd think they would be trying to catch the fairing while the boat was in motion. If so they that implies communications between the boat and the parachute system so that they can be cooperative in the landing.

Will this violate the Blue Origin patent?  Or did that get thrown out after 20 successful SpaceX landings?
Title: Re: Fairing reuse
Post by: nacnud on 12/20/2017 04:47 pm
I think that patent got invalidated

https://www.geekwire.com/2015/blue-origins-rocket-landing-patent-canceled-in-victory-for-spacex/
Title: Re: Fairing reuse
Post by: the_other_Doug on 12/20/2017 04:52 pm
It's pretty clear to me that the reason is to buy mass for the fairing recovery experiment, but @IridiumBoss isn't allowed to say that (or is just being polite by not spoiling SpaceX's announcement).  That explains his coy answers.

I said it before and I'll say it again, I think you're vastly underestimating the performance reserve SpaceX have for this flight and the leeway in the recovery method they therefore could choose if the reserve is deemed insufficient for the recovery method using a boostback burn.

Perhaps.  There is L2 info re: the re-entry profile, maybe we'll discuss that further there.  My post was stating a cause-and-effect: @IridiumBoss' coy response, which seems to hint at the key factor being something he can't directly disclose, was making me more certain. I should have written "It's becoming more clear to me" instead of just "It's pretty clear to me" to make the point clearer. As you mention, the actual reasoning is in other posts, I didn't feel I had to repeat that.

And I'm not claiming the fairing experiment is the *only* factor.  Just that it's one piece which, combined with the other issues discussed here (block 3, lack of space, etc), may have pushed the decision over the edge into expendibility.

Seeing as what is now the Zuma booster (definitely *not* a Block 5) was going to launch this Iridium flight, and that it was going to perform the first Vandenberg RTLS recovery, I would have to think that a Block 3 is way more than capable of any number of ASDS recovery trajectories, even with a few hundred extra pounds of fairing recovery gear aboard, with so much energy to spare they could experiment with ASDS touch-and-go's... :)
Title: Re: Fairing reuse
Post by: matthewkantar on 12/20/2017 05:42 pm
One way to catch both halves with one rig is to have one net deployed and lowerable with winches while the other net is furled and stretched between two of the masts. Line would go from each end of the furled net to the opposite mast on each side, through a pulley and to another winch. This would be similar to how a rubber-banded spinnaker is released on sail boat.

The first fairing hits and is lowered to the deck in maybe fifteen seconds. The second net is deployed by running the winches, in a minute or so, and the second half is caught. This would explain the height of the masts on Mr Steven.

Matthew
Title: Re: Fairing reuse
Post by: rakaydos on 12/20/2017 07:53 pm
One way to catch both halves with one rig is to have one net deployed and lowerable with winches while the other net is furled and stretched between two of the masts. Line would go from each end of the furled net to the opposite mast on each side, through a pulley and to another winch. This would be similar to how a rubber-banded spinnaker is released on sail boat.

The first fairing hits and is lowered to the deck in maybe fifteen seconds. The second net is deployed by running the winches, in a minute or so, and the second half is caught. This would explain the height of the masts on Mr Steven.

Matthew
For bonus points, have a 3rd net on the other side, to secure the top fairing for transport.
Title: Re: Fairing reuse
Post by: Jcc on 12/20/2017 11:06 pm
How's this arrangement to capture 2 fairing halves: two nets, one attached on the left side, with cables to pull it open to the right side. The other net attached on the right, with cables that pull it open to the left. Start with both nets folded, first pull the cables to stretch out the left net, capture one fairing half, then pull the cables back to fold the left net with the fairing half inside, and stow it to the left of the deck. Next open the right net, capture the other fairing half, then fold it back to stow the fairing.
Title: Re: Fairing reuse
Post by: robert_d on 12/21/2017 12:28 am
How's this arrangement to capture 2 fairing halves: two nets, one attached on the left side, with cables to pull it open to the right side. The other net attached on the right, with cables that pull it open to the left. Start with both nets folded, first pull the cables to stretch out the left net, capture one fairing half, then pull the cables back to fold the left net with the fairing half inside, and stow it to the left of the deck. Next open the right net, capture the other fairing half, then fold it back to stow the fairing.

We may not be seeing everything yet by I like this idea better. I am thinking that lack of attach points may actually argue against a complicated net and winch system. It may possibly indicate 2 inflatable structures, port and starboard that would catch the fairings coming in from behind at say a 15 degree angle. They would slide to the center with a center cushion to prevent contact.
Title: Re: Fairing reuse
Post by: IanThePineapple on 12/21/2017 12:58 am
How's this arrangement to capture 2 fairing halves: two nets, one attached on the left side, with cables to pull it open to the right side. The other net attached on the right, with cables that pull it open to the left. Start with both nets folded, first pull the cables to stretch out the left net, capture one fairing half, then pull the cables back to fold the left net with the fairing half inside, and stow it to the left of the deck. Next open the right net, capture the other fairing half, then fold it back to stow the fairing.

We may not be seeing everything yet by I like this idea better. I am thinking that lack of attach points may actually argue against a complicated net and winch system. It may possibly indicate 2 inflatable structures, port and starboard that would catch the fairings coming in from behind at say a 15 degree angle. They would slide to the center with a center cushion to prevent contact.

The boat may not even be in its final form ( ;D ), it might not even be ready for this mission. There could still be quite a bit more work needed on it, like how 39A's TEL looked in one of our first glimpses of it (http://i.imgur.com/o64Whbk.jpg (http://i.imgur.com/o64Whbk.jpg)).
Title: Re: Fairing reuse
Post by: Lar on 12/21/2017 01:16 am
maybe but dubious. Why rush Mr. Steven over here when there are several missions on the other coast that will be ejecting pallets of cash, er fairings.
Title: Re: Fairing reuse
Post by: cscott on 12/21/2017 01:24 am
I wonder if GO Mr. Steven can fit back through the Panama Canal with this superstructure on it?
Title: Re: Fairing reuse
Post by: speedevil on 12/21/2017 01:40 am
I wonder if GO Mr. Steven can fit back through the Panama Canal with this superstructure on it?

Easily.
This is a 'tiny' ship - it is only 9m wide, and with the fairing support structure only ~15m wide.
The ASDS fit through the canal with only removal of the 'wings', and that's more 90m wide than 9.
Title: Re: Fairing reuse
Post by: Lar on 12/21/2017 01:49 am
you think the fairing support arms are only 3M beyond the hull? I think someone would need to measure it but I'm dubious, more like almost the hull width again on each side. but I could be wrong.

That still easily fits through the canal but I see it as quite ungainly.
Title: Re: Fairing reuse
Post by: speedevil on 12/21/2017 02:14 am
you think the fairing support arms are only 3M beyond the hull? I think someone would need to measure it but I'm dubious, more like almost the hull width again on each side. but I could be wrong.

That still easily fits through the canal but I see it as quite ungainly.
Hmm.

The ship is only 205 feet long, 65m or so.
The arms spacing fore-aft at the tips is around 1/2.2* the ships length, or 29m. I think I may have initially measured the bases, and then forgotten what I was measuring.

Measuring more carefully using:
 (https://i.imgur.com/iftQyLG.jpg?1)
gives around 26m from tip-tip.

This is consistent with a 25 or 26m square, about 13m off the deck.
(https://marssettlement.files.wordpress.com/2013/05/falcon9fairing17ft.jpg) for reference.

So, the fairing can be ten meters off centre in port-starboard, or some five meters in fore-aft inaccuracy without coming off a hypothetical square net.
Or rather more than that in fore-aft if we consider  the ends poking over. There is a _lot_ of vertical space below the net, and forward of the net, meaning the first one could be slid off onto the deck rapidly while awaiting the next.
This is probably needless complexity for a first attempt.
Title: Re: Fairing reuse
Post by: cppetrie on 12/21/2017 04:30 am
I’m not convinced that the arms aren’t mounted on rotating bases that would allow the arms to ‘fold’ in and lie within the draft of the vessel. It’s unclear whether they would be hydraulically driven or just manual with locking pins. The latter is certainly simpler.
Title: Re: Fairing reuse
Post by: speedevil on 12/21/2017 12:08 pm
I’m not convinced that the arms aren’t mounted on rotating bases that would allow the arms to ‘fold’ in and lie within the draft of the vessel. It’s unclear whether they would be hydraulically driven or just manual with locking pins. The latter is certainly simpler.

It would complicate the structure, and is only really needed to go under low bridges, (low in marine contexts anyway) and to lie directly next to a >8m tall structure or ship.
Many fishing boats have sticky-out bits protruding from their outline, and nearly all harbours do not have a tidal range this great.
If it was not welded in place to a beam, I would suspect that there would be some mechanism visible, but it's quite possible either way.
Title: Re: Fairing reuse
Post by: Johnnyhinbos on 12/21/2017 02:38 pm
Yeah, I think it’s 100% probable that the arms rotate aft. That’s a solved problem that you can see on any derrick, davit, hoist, and crane.

Edit to add that fishing trawlers only run outriggers outboard once underway. I keep my 46’ Saber Hardtop Express in New Bedford, MA amongst hundreds of 100’ trawlers. They’re packed in like sardines, hull to hull.

Those arms 100% rig aft.
Title: Re: Fairing reuse
Post by: dorkmo on 12/21/2017 03:49 pm
to me it looked like there was a big hunky base sort the width and length of a shipping container that had short stands coming out from its corners that the arms appear to bolt to. if its not a rotating mechanism i'd guess it could at least be un bolted.
Title: Re: Fairing reuse
Post by: RDMM2081 on 12/21/2017 04:55 pm
There might be a very obvious answer to this question but since it's not obvious to me I'll ask it.
      Why can't the two halves be caught in the same net despite contact. Would the damage be that great that would render the effort worthless? I don't know enough about the material and speed of landing to be able to discern the impact.
     Also seems to me that the first try is more about catching than using the fairings that were caught.

I am not sure about this at all, but my speculation is that Mr. Steven will be catching exactly one half of the fairing this attempt.  Any of the "multiple catch" scenarios (except maybe the double decker net) or offloading between catches treat these fairings much more robustly than I think they are built.  The cost estimates are currently somewhere between "pallet of cash" and the $6m neighborhood of comparable fairings.  To me, this means that these are complicated, expensive, and therefore fragile, delicate, high grade aerospace carbon composite structures that cannot be "slid" off nets, or moved by hand, or hastily moved by crane.  I think any contact between the halves would be an instant deal-breaker as well.  This is why I suspect that they will catch only one half this attempt.

Supposing that they do in fact catch only one half this time, will it be able to be re-used?  What I mean, is are the fairing halves built to be paired with a specific second half, or are they interchangeable, even in theory?  If they catch one half, or course it is good practice for future efforts and proof of concept, but without the second "matching" (I in no way claim to know that they need to be matched, but it seems possible to me at first thought) fairing half, is it potentially useless for reuse?
Title: Re: Fairing reuse
Post by: cscott on 12/21/2017 05:01 pm
They are built/cured one half at a time; I assume they could build a matching passive half if needed.
Title: Re: Fairing reuse
Post by: cppetrie on 12/21/2017 05:10 pm
Given what the fairing has to withstand during launch and max q, I’m not sure fragile is the right word. I do however think they are designed to handle only certain kinds of loads in a robust way. Contact between them is unlikely to be a mode for which they are designed. Contact would likely result in some level of cracking, chipping or delamination that would make it structurally unsound to fly again through max q.
Title: Re: Fairing reuse
Post by: leetdan on 12/21/2017 05:14 pm
An empty soda can is "fragile" if you squeeze the sides, but not if you stand on it.  Just because the joined fairing is strong against aero loads doesn't mean a separated fairing will survive rough handling or impacts.
Title: Re: Fairing reuse
Post by: RDoc on 12/21/2017 05:28 pm
I'd not be surprised if jcc was close https://forum.nasaspaceflight.com/index.php?topic=37727.msg1761981#msg1761981 (https://forum.nasaspaceflight.com/index.php?topic=37727.msg1761981#msg1761981). Two large floating air cushions, port and starboard, one per half. One issue I see with nets is t some kind of shock absorbing mechanism the fairing half will decelerate pretty quickly.
Title: Re: Fairing reuse
Post by: cppetrie on 12/21/2017 05:57 pm
I'd not be surprised if jcc was close https://forum.nasaspaceflight.com/index.php?topic=37727.msg1761981#msg1761981 (https://forum.nasaspaceflight.com/index.php?topic=37727.msg1761981#msg1761981). Two large floating air cushions, port and starboard, one per half. One issue I see with nets is t some kind of shock absorbing mechanism the fairing half will decelerate pretty quickly.
Pretty easy to add some shock absorbing to the net. Think trapeze safety net. Some springs at the mount points plus the tensioning cables and netting material will have some inherent stretch and thus shock absorption capacity.
Title: Re: Fairing reuse
Post by: Survtech on 12/21/2017 08:02 pm
There might be a very obvious answer to this question but since it's not obvious to me I'll ask it.
      Why can't the two halves be caught in the same net despite contact. Would the damage be that great that would render the effort worthless? I don't know enough about the material and speed of landing to be able to discern the impact.
     Also seems to me that the first try is more about catching than using the fairings that were caught.

I am not sure about this at all, but my speculation is that Mr. Steven will be catching exactly one half of the fairing this attempt.  Any of the "multiple catch" scenarios (except maybe the double decker net) or offloading between catches treat these fairings much more robustly than I think they are built.  The cost estimates are currently somewhere between "pallet of cash" and the $6m neighborhood of comparable fairings.  To me, this means that these are complicated, expensive, and therefore fragile, delicate, high grade aerospace carbon composite structures that cannot be "slid" off nets, or moved by hand, or hastily moved by crane.  I think any contact between the halves would be an instant deal-breaker as well.  This is why I suspect that they will catch only one half this attempt.

Supposing that they do in fact catch only one half this time, will it be able to be re-used?  What I mean, is are the fairing halves built to be paired with a specific second half, or are they interchangeable, even in theory?  If they catch one half, or course it is good practice for future efforts and proof of concept, but without the second "matching" (I in no way claim to know that they need to be matched, but it seems possible to me at first thought) fairing half, is it potentially useless for reuse?
Probably not this time.  As of 1:00 PM PST today, December 21, which is less than 29 hours from the launch target, Mr. Steven is still moored in San Pedro.  I assume it should have left port by now if it's going to attempt a fairing recovery. https://www.marinetraffic.com/en/ais/home/shipid:3439091/zoom:14
Title: Re: Fairing reuse
Post by: RDoc on 12/21/2017 08:12 pm
I'd not be surprised if jcc was close https://forum.nasaspaceflight.com/index.php?topic=37727.msg1761981#msg1761981 (https://forum.nasaspaceflight.com/index.php?topic=37727.msg1761981#msg1761981). Two large floating air cushions, port and starboard, one per half. One issue I see with nets is t some kind of shock absorbing mechanism the fairing half will decelerate pretty quickly.
Pretty easy to add some shock absorbing to the net. Think trapeze safety net. Some springs at the mount points plus the tensioning cables and netting material will have some inherent stretch and thus shock absorption capacity.
But the arms still need to absorb the force of the landing.

Floating mats on the other hand just need to be secured to the ship. The force is very spread out with the ocean as the support structure. A simple air bag like pressure release release system could be the shock absorber.

Such a system would provide a much larger pair of targets too.
Title: Re: Fairing reuse
Post by: RocketLover0119 on 12/21/2017 08:24 pm
As of a few min. ago, Mr. Steven is still docked, however, NRC quest has vanished from the dock

EDIT: just checked and NRC quest is well offshore heading to where the fairings may be.... Mr Steven sitting this one out?
Title: Re: Fairing reuse
Post by: Survtech on 12/21/2017 08:32 pm
As of a few min. ago, Mr. Steven is still docked, however, NRC quest has vanished from the dock

EDIT: just checked and NRC quest is well offshore heading to where the fairings may be.... Mr Steven sitting this one out?
NRC Quest is currently (1:31 PM PST) just south of Santa Catalina Island, heading almost due South (185 degrees) at 9.7 knots. https://www.marinetraffic.com/en/ais/home/shipid:447294/zoom:10
Title: Re: Fairing reuse
Post by: AncientU on 12/21/2017 08:50 pm
As of a few min. ago, Mr. Steven is still docked, however, NRC quest has vanished from the dock

EDIT: just checked and NRC quest is well offshore heading to where the fairings may be.... Mr Steven sitting this one out?
NRC Quest is currently (1:31 PM PST) just south of Santa Catalina Island, heading almost due South (185 degrees) at 9.7 knots. https://www.marinetraffic.com/en/ais/home/shipid:447294/zoom:10

Mr Steven is fast enough to wait until morning to get under way.
Title: Re: Fairing reuse
Post by: cppetrie on 12/21/2017 09:12 pm
I'd not be surprised if jcc was close https://forum.nasaspaceflight.com/index.php?topic=37727.msg1761981#msg1761981 (https://forum.nasaspaceflight.com/index.php?topic=37727.msg1761981#msg1761981). Two large floating air cushions, port and starboard, one per half. One issue I see with nets is t some kind of shock absorbing mechanism the fairing half will decelerate pretty quickly.
Pretty easy to add some shock absorbing to the net. Think trapeze safety net. Some springs at the mount points plus the tensioning cables and netting material will have some inherent stretch and thus shock absorption capacity.
But the arms still need to absorb the force of the landing.

Floating mats on the other hand just need to be secured to the ship. The force is very spread out with the ocean as the support structure. A simple air bag like pressure release release system could be the shock absorber.

Such a system would provide a much larger pair of targets too.
By the looks of them those arms are more than strong enough to withstand the force of the fairings landing. Big giant air cushions on the water’s surface would require a crane of some sort to move the fairing from the cushions to the deck for the ride home. If caught in a netting strung between the arms then the net is simply lowered and the fairings secured for transport. A cradle on deck is all that would be needed to secure the halves upon lowering.
Title: Re: Fairing reuse
Post by: jabe on 12/21/2017 09:31 pm
i may be out of loop.. or missed a comment...there are two halves..how is 2nd half caught? 2nd boat?
jb
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 12/21/2017 09:32 pm
Cross-posting:

A type of reuse I haven’t noticed customers discussing before:

Quote
@IridiumBoss with the move to allow using flight proven cores, would Iridium now be open to being the first company to use reused Fairings?

https://twitter.com/beeberunner/status/943544314096955397

Quote
We're open to anything if it can be proven to improve risk, schedule and cost.  We're about getting our amazing next generation network in space as fast and safely as we can, not creating history for its own sake (though happy to do that this week with our fourth launch)!

https://twitter.com/iridiumboss/status/943547579001987073

Customer views on reuse belong in the original thread, but I’m posting here due to the last comment. Evidence of more significant fairing recovery attempt this time?
Title: Re: Fairing reuse
Post by: nacnud on 12/21/2017 09:40 pm
i may be out of loop.. or missed a comment...there are two halves..how is 2nd half caught? 2nd boat?
jb

Probably just catching the one half this time. Much speculation as to how the 2nd half is caught, no answers yet.
Title: Re: Fairing reuse
Post by: RocketLover0119 on 12/21/2017 10:13 pm
totally speculating, but maybe on Iridium 4 one half will go to Mr. steven and the other NRC Quest ???

i may be out of loop.. or missed a comment...there are two halves..how is 2nd half caught? 2nd boat?
jb

Probably just catching the one half this time. Much speculation as to how the 2nd half is caught, no answers yet.


 
Title: Re: Fairing reuse
Post by: envy887 on 12/21/2017 10:22 pm
Cross-posting:

A type of reuse I haven’t noticed customers discussing before:

Quote
@IridiumBoss with the move to allow using flight proven cores, would Iridium now be open to being the first company to use reused Fairings?

https://twitter.com/beeberunner/status/943544314096955397

Quote
We're open to anything if it can be proven to improve risk, schedule and cost.  We're about getting our amazing next generation network in space as fast and safely as we can, not creating history for its own sake (though happy to do that this week with our fourth launch)!

https://twitter.com/iridiumboss/status/943547579001987073

Customer views on reuse belong in the original thread, but I’m posting here due to the last comment. Evidence of more significant fairing recovery attempt this time?

I think he's referring to being the first company to buy two launches on the same booster.
Title: Re: Fairing reuse
Post by: Flying Beaver on 12/22/2017 12:53 am
Mr. Steven is currently underway at 15 knots just east of Catalina Island, destination reading as Guadalupe Island, which i'd say is in approximate area for a fairing recovery with extended stage 1 burn (600km downrange).
Title: Re: Fairing reuse
Post by: llanitedave on 12/22/2017 03:44 am
Ok, super crazy idea (perhaps wine-induced), so bear with me.

How feasible would it be to tether the fairing mid-flight to the boat and parasail the thing down to the cradle/claw basket by winching it down in a controlled fashion? Once tethered, the boat's speed could be used to raise altitude or keep the fairing from falling too fast until it is caught.

Presumably, all the equipment the fairing would need would be a [right type of] parachute system and a long enough tether to hang down so the boat can catch the tether before the fairing hits the water.

It sounds James Bond enough for SpaceX  ;D

Whatever wine you're having, I'll take a glass!
Title: Re: Fairing reuse
Post by: JamesH65 on 12/22/2017 09:54 am
I'd not be surprised if jcc was close https://forum.nasaspaceflight.com/index.php?topic=37727.msg1761981#msg1761981 (https://forum.nasaspaceflight.com/index.php?topic=37727.msg1761981#msg1761981). Two large floating air cushions, port and starboard, one per half. One issue I see with nets is t some kind of shock absorbing mechanism the fairing half will decelerate pretty quickly.
Pretty easy to add some shock absorbing to the net. Think trapeze safety net. Some springs at the mount points plus the tensioning cables and netting material will have some inherent stretch and thus shock absorption capacity.
But the arms still need to absorb the force of the landing.

Floating mats on the other hand just need to be secured to the ship. The force is very spread out with the ocean as the support structure. A simple air bag like pressure release release system could be the shock absorber.

Such a system would provide a much larger pair of targets too.

Hitting water with a flexible cover on it is almost like hitting concrete. The water DOES NOT GIVE. As a one time windsurfer, I was flipped and hit the sail lying flat on the surface. Quite quickly. Nearly knocked me out.  So you would need large floating air bags to absorb ALL the impact - the water doesn't help.

So just use a sodding great big net. Much easier, easy to make very shock absorbing (check out people diving down on nets from a long way up - less mass, but easily scalable), and easy to simply lower one net and slide another one over the top for the second half of the fairly. The fairings are not hugely heavy.

Don't over think this - Musk hasn't.

Title: Re: Fairing reuse
Post by: vanoord on 12/22/2017 01:34 pm
Floating mats on the other hand just need to be secured to the ship. The force is very spread out with the ocean as the support structure. A simple air bag like pressure release release system could be the shock absorber.

Such a system would provide a much larger pair of targets too.

A potential advantage of putting a big net on top of the ship is the ability to move the net at the last minute / have the net moving to reduce the relative speed during the final approach.
Title: Re: Fairing reuse
Post by: speedevil on 12/22/2017 01:45 pm
A potential advantage of putting a big net on top of the ship is the ability to move the net at the last minute / have the net moving to reduce the relative speed during the final approach.
The net weighs orders of magnitude less than the fairing, so the impact even without any other measures is going to be quite soft.
Title: Re: Fairing reuse
Post by: meekGee on 12/22/2017 01:53 pm
Floating mats on the other hand just need to be secured to the ship. The force is very spread out with the ocean as the support structure. A simple air bag like pressure release release system could be the shock absorber.

Such a system would provide a much larger pair of targets too.

A potential advantage of putting a big net on top of the ship is the ability to move the net at the last minute / have the net moving to reduce the relative speed during the final approach.

I don't think the final approach of the parachute system will intersect the net.

I think the last 1-2 seconds will be in free-fall, to minimize last-second wind effects, and to make the trajectory more vertical (and thus more perpendicular to the net)

I think the parachute system will sweep high, by 10-20', overtaking the ship, but making sure the IIP intersects the ship's path.  Then it's just a matter of timing the release correctly, the fairing drops, and the net catches it.

Meanwhile the parachute, having been released early, falls back and does not add post-landing complications.

Title: Re: Fairing reuse
Post by: LouScheffer on 12/22/2017 03:59 pm
I don't think the final approach of the parachute system will intersect the net.

I think the last 1-2 seconds will be in free-fall, to minimize last-second wind effects, and to make the trajectory more vertical (and thus more perpendicular to the net)

If you watch human parachuters trying to hit a target, then come down steeply but not vertically, and they keep adjusting to the very last second.  Dropping seems worse for last-minute winds.  You still need to hit the drop point exactly, but then you can't adjust any further.

Also, the boat is quite fast.   If it maneuvers under the parachute, and matches the horizontal component of velocity, then the fairing comes down perpendicular to the net with no relative horizontal velocity.  And this way you keep control right up until capture, with the lowest impact speed into the net.  So I expect it to work like an aircraft carrier, with the parachute under positive control and the ship moving into the wind to minimize the relative velocity.
Title: Re: Fairing reuse
Post by: meekGee on 12/22/2017 05:25 pm
I don't think the final approach of the parachute system will intersect the net.

I think the last 1-2 seconds will be in free-fall, to minimize last-second wind effects, and to make the trajectory more vertical (and thus more perpendicular to the net)

If you watch human parachuters trying to hit a target, then come down steeply but not vertically, and they keep adjusting to the very last second.  Dropping seems worse for last-minute winds.  You still need to hit the drop point exactly, but then you can't adjust any further.

Also, the boat is quite fast.   If it maneuvers under the parachute, and matches the horizontal component of velocity, then the fairing comes down perpendicular to the net with no relative horizontal velocity.  And this way you keep control right up until capture, with the lowest impact speed into the net.  So I expect it to work like an aircraft carrier, with the parachute under positive control and the ship moving into the wind to minimize the relative velocity.
Just like with F9 landings, the way humans do it is dictated by how humans process information.

A helicopter pilots hovers and adjusts continuously, and then lands slowly.  A computer hover slams.

A falling fairing, in 1-2 seconds, even in changing wind, is predictable.

A parachutes OTOH has a huge sail area, and not enough authority to combat a gust of wind in real time.

If a human tried to land on a moving ship in open seas, they'd likely miss.  Plus, they typically don't have a net to arrest vertical motion.  (Except for that one guy..)
Title: Re: Fairing reuse
Post by: RDoc on 12/22/2017 06:17 pm
I'd not be surprised if jcc was close https://forum.nasaspaceflight.com/index.php?topic=37727.msg1761981#msg1761981 (https://forum.nasaspaceflight.com/index.php?topic=37727.msg1761981#msg1761981). Two large floating air cushions, port and starboard, one per half. One issue I see with nets is t some kind of shock absorbing mechanism the fairing half will decelerate pretty quickly.
Pretty easy to add some shock absorbing to the net. Think trapeze safety net. Some springs at the mount points plus the tensioning cables and netting material will have some inherent stretch and thus shock absorption capacity.
But the arms still need to absorb the force of the landing.

Floating mats on the other hand just need to be secured to the ship. The force is very spread out with the ocean as the support structure. A simple air bag like pressure release release system could be the shock absorber.

Such a system would provide a much larger pair of targets too.

Hitting water with a flexible cover on it is almost like hitting concrete. The water DOES NOT GIVE. As a one time windsurfer, I was flipped and hit the sail lying flat on the surface. Quite quickly. Nearly knocked me out.  So you would need large floating air bags to absorb ALL the impact - the water doesn't help.

So just use a sodding great big net. Much easier, easy to make very shock absorbing (check out people diving down on nets from a long way up - less mass, but easily scalable), and easy to simply lower one net and slide another one over the top for the second half of the fairly. The fairings are not hugely heavy.

Don't over think this - Musk hasn't.
Nobody's talking about a flexible cover.
Title: Re: Fairing reuse
Post by: Req on 12/22/2017 06:23 pm
Some very good pictures of the inside of the fairings from Elon Musk's instragram.  I only post them here because there has been so much discussion around extra recovery hardware recently, and because these may be some of the most detailed images of fairings that we know to be are presumably recovery-enabled so far.
Title: Re: Fairing reuse
Post by: dorkmo on 12/23/2017 05:03 am
http://forum.nasaspaceflight.com/index.php?topic=43149.msg1692094#msg1692094

Could the stuff near the top be an area for 3 copv to be mounted? Maybe the fab shop made a reusable half but they later decided not to fit it out with all the plumbing.

https://www.flickr.com/photos/spacex/39225582801/in/photostream/

you can see the upper copvs are mounted in the Roadster fairing, while they were not on the iridium-2

looks like they replaced the chute bags at the base with a black tube, i wonder if thats a droge cannon or something?

edit: i'd also note that the roadster fairings dont yet have all their standard hardware installed, so this is kind of a "dummy" encapsilation photo shoot. there could be more recovery/chute devices than we are seeing here.
Title: Re: Fairing reuse
Post by: Dave G on 12/23/2017 12:45 pm
Mr. Steven is currently underway at 15 knots just east of Catalina Island, destination reading as Guadalupe Island, which i'd say is in approximate area for a fairing recovery with extended stage 1 burn (600km downrange).

Does anyone have more news on the fairing recovery attempt last night?
Title: Re: Fairing reuse
Post by: scdavis on 12/23/2017 02:50 pm
http://forum.nasaspaceflight.com/index.php?topic=43149.msg1692094#msg1692094

you can see the upper copvs are mounted in the Roadster fairing, while they were not on the iridium-2

looks like they replaced the chute bags at the base with a black tube, i wonder if thats a droge cannon or something?

I see two cylinders near the top of the left fairing and one at the bottom of the right fairing -- is this what you're saying are copv's for cold gas thrusters?

Black tube... far bottom-left corner of the left fairing?

Are there pics in the forums of the inside of previous fairings for comparison? I haven't been able to find them.
Title: Re: Fairing reuse
Post by: nacnud on 12/23/2017 02:59 pm
I see two cylinders near the top of the left fairing and one at the bottom of the right fairing -- is this what you're saying are copv's for cold gas thrusters?

The ones on the left fairing are, I think, for cold gas thrusters. Remember only one fairing has recovery hardware installed. They are also in the right place center of gravity wise for a falling fairing. You can see some pipes near the top of the left fairing that could be supplying gas to thrusters. The ones on the right power the separation pushers, you can follow the pipes to each separation mechanism.

Quote
Black tube... far bottom-left corner of the left fairing?
Yes, parachutes would depoy from that area and probably aren't installed yet. I don't know what the corrugated black tubes are, perhaps umbilicals to supply the payload with conditioned air etc. I've no insider info, just what I can see in the pics.

Title: Re: Fairing reuse
Post by: Johnnyhinbos on 12/23/2017 03:27 pm
http://forum.nasaspaceflight.com/index.php?topic=43149.msg1692094#msg1692094

you can see the upper copvs are mounted in the Roadster fairing, while they were not on the iridium-2

looks like they replaced the chute bags at the base with a black tube, i wonder if thats a droge cannon or something?

I see two cylinders near the top of the left fairing and one at the bottom of the right fairing -- is this what you're saying are copv's for cold gas thrusters?

Black tube... far bottom-left corner of the left fairing?

Are there pics in the forums of the inside of previous fairings for comparison? I haven't been able to find them.
I think the black tubes are for distribution of environmental control (HVAC). You see they terminate at a bulkhead - i.e. the attachment point for the fairing umbilical. This would be asymmetrical because I believe there's only one umbilical not a matched set...
Title: Re: Fairing reuse
Post by: dorkmo on 12/23/2017 04:25 pm
i guess theres a lot of black cylinders around :D

heres the one im thinking about. i thought it was interesting that this is previously where what was thought to be the chute bags were
Title: Re: Fairing reuse
Post by: Johnnyhinbos on 12/23/2017 05:07 pm
i guess theres a lot of black cylinders around :D

heres the one im thinking about. i thought it was interesting that this is previously where what was thought to be the chute bags were
One interesting thing about that area is the two angled "channels" that are masked off in small squares. To me those look like channels under which parachute canopy lines run. Similar to what's seen on the outside of a Dragon capsule.  they angle towards the top of that black cylinder - which could perhaps be a drogue cannon?
Title: Re: Fairing reuse
Post by: nacnud on 12/23/2017 05:09 pm
i guess theres a lot of black cylinders around :D

heres the one im thinking about. i thought it was interesting that this is previously where what was thought to be the chute bags were
One interesting thing about that area is the two angled "channels" that are masked off in small squares. To me those look like channels under which parachute canopy lines run. Similar to what's seen on the outside of a Dragon capsule.  they angle towards the top of that black cylinder - which could perhaps be a drogue cannon?

Exactly what I was thinking. I couldn't see where the bridle might be mounted at the top of the left fairing though.
Title: Re: Fairing reuse
Post by: Lar on 12/23/2017 08:49 pm
whether that drogue cannon actually is one or not, it does seem to stick a ways inwards, perhaps even enough to impinge the payload envelope? What helps is that it's at the very bottom where the envelope tapers inward diagonally.
Title: Re: Fairing reuse
Post by: garcianc on 12/23/2017 10:29 pm
whether that drogue cannon actually is one or not, it does seem to stick a ways inwards, perhaps even enough to impinge the payload envelope? What helps is that it's at the very bottom where the envelope tapers inward diagonally.
Looking at the Falcon 9 User's Guide, it looks like that would fall outside of the dynamic envelope (if I am looking at the picture correctly).
Title: Re: Fairing reuse
Post by: cscott on 12/23/2017 11:44 pm
If I'm reading that diagram correctly, they'll sell you space below the adapter ring (where the drogue would go) if the price is right.

I expect the price would approach $6 million if your desired volume impinged on the recovery hardware.
Title: Re: Fairing reuse
Post by: Flying Beaver on 12/24/2017 12:24 am
Mr Steven is tracking back to port now at 18 knots. Current ETA 1-2am local (PT) tomorrow morning, approx 10 hours from now.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 12/24/2017 07:11 am
Mr Steven is tracking back to port now at 18 knots. Current ETA 1-2am local (PT) tomorrow morning, approx 10 hours from now.

Looking a bit later now, but still doing 18 knots and about to pass St Clemente Island. Now within range of land based detection so visible on MarineTraffic etc without subscription.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 12/24/2017 09:00 am
Mr Steven is now passing Santa Catalina Island, so on the home stretch. Current ETA is 04:30 local (12:30 UTC).
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 12/24/2017 10:29 am
ETA was a bit off! Mr Steven is now in the harbour about to enter the East channel, so near its berth.
Title: Re: Fairing reuse
Post by: sevenperforce on 12/24/2017 01:36 pm
I've got Mr. Steven and NRC Quest both stopped at what looks like their dock. Searching for port cams.

This  (https://www.webcamtaxi.com/en/usa/california/port-of-los-angeles.html)is the only one I've found, and of course it's way too far...
Title: Re: Fairing reuse
Post by: cscott on 12/24/2017 02:05 pm
Planet Lab does a pass at 10am local each day, if I understand correctly.  Maybe they would post an image?
Title: Re: Fairing reuse
Post by: meekGee on 12/24/2017 02:52 pm
I'm not optimistic.  The 4 am return time is not helping.  Hope Mr. Steven is not dinged or scratched.
Title: Re: Fairing reuse
Post by: sevenperforce on 12/24/2017 03:33 pm
I'm not optimistic.  The 4 am return time is not helping.  Hope Mr. Steven is not dinged or scratched.
Yeah, you'd think SOMETHING would have leaked by now.

Ah, well, it took a while to get ASDS landings down.
Title: Re: Fairing reuse
Post by: meekGee on 12/24/2017 03:34 pm
Also how they stayed put till daytime before getting under way.

We'll find out soon enough.
Title: Re: Fairing reuse
Post by: chawleysnow on 12/24/2017 04:01 pm
Took a quick drive around the harbor this morning. Long story short, nothing interesting enough to try and get pictures on a crappy iPhone camera. Mr Steven is back, all four arms appear to be attached and unchanged from previous photos. No evidence of any nets, bouncy castles, or fairing halves visible from public roads.
Title: Re: Fairing reuse
Post by: Coastal Ron on 12/24/2017 04:16 pm
Took a quick drive around the harbor this morning. Long story short, nothing interesting enough to try and get pictures on a crappy iPhone camera. Mr Steven is back, all four arms appear to be attached and unchanged from previous photos. No evidence of any nets, bouncy castles, or fairing halves visible from public roads.

Maybe this was a dry-run to test everything without actually committing to a capture?
Title: Re: Fairing reuse
Post by: sevenperforce on 12/24/2017 04:20 pm
Took a quick drive around the harbor this morning. Long story short, nothing interesting enough to try and get pictures on a crappy iPhone camera. Mr Steven is back, all four arms appear to be attached and unchanged from previous photos. No evidence of any nets, bouncy castles, or fairing halves visible from public roads.

Maybe this was a dry-run to test everything without actually committing to a capture?
Or could just be a miss. A tangled line on the chute spiraling the fairing half into the drink.
Title: Re: Fairing reuse
Post by: meekGee on 12/24/2017 04:23 pm
Took a quick drive around the harbor this morning. Long story short, nothing interesting enough to try and get pictures on a crappy iPhone camera. Mr Steven is back, all four arms appear to be attached and unchanged from previous photos. No evidence of any nets, bouncy castles, or fairing halves visible from public roads.

Maybe this was a dry-run to test everything without actually committing to a capture?
Or could just be a miss. A tangled line on the chute spiraling the fairing half into the drink.
Typical...
Title: Re: Fairing reuse
Post by: cscott on 12/24/2017 04:34 pm
Or the doc ock isn't complete in time (ie, no nets or bouncy castles) so this was a dry run.  Just like it's looking like JRtI was down for repairs, causing the "dry run" ASDS landing.

Or else my theory of a week ago was correct, ad this did have a bunch of fancy mass-y new recovery gear... but it didn't work right.

Maybe we'll get some word from SpaceX, maybe we'll never know.
Title: Re: Fairing reuse
Post by: Rangertech1 on 12/24/2017 09:48 pm
Or the doc ock isn't complete in time (ie, no nets or bouncy castles) so this was a dry run.  Just like it's looking like JRtI was down for repairs, causing the "dry run" ASDS landing.

Or else my theory of a week ago was correct, ad this did have a bunch of fancy mass-y new recovery gear... but it didn't work right.

Maybe we'll get some word from SpaceX, maybe we'll never know.

If you follow the crew of Mr Steven and they head straight for a bar, that might be a useful piece of evidence of how things went.
Title: Re: Fairing reuse
Post by: Lar on 12/24/2017 11:10 pm
That's kind of stalky and no one is advocating that anyone actually do that. :)
Title: Re: Fairing reuse
Post by: garcianc on 12/25/2017 01:31 am
If you follow the crew of Mr Steven and they head straight for a bar, that might be a useful piece of evidence of how things went.
Evidence that they are Sailors  ;)
Title: Re: Fairing reuse
Post by: AncientU on 12/25/2017 11:52 am
That's kind of stalky and no one is advocating that anyone actually do that. :)

Without buying them a beer, of course.
Title: Re: Fairing reuse
Post by: octavo on 12/26/2017 04:34 am
I haven't seen this posted here yet: on the SpaceX FB group Pauline Acalin posted a pic of Mr. Steven in Port with rigging across those 4 arms. What can the detectives here sleuth from this?

Link to FB thread where image appears:
https://m.facebook.com/groups/2387776317?view=permalink&id=10156138270661318

ETA: Attached here directly, with permission from Pauline. (https://uploads.tapatalk-cdn.com/20171226/115188ad08a69ba351cc68a7cc26ad3f.jpg)
Title: Re: Fairing reuse
Post by: IanThePineapple on 12/26/2017 04:53 am
Or the doc ock isn't complete in time (ie, no nets or bouncy castles) so this was a dry run.  Just like it's looking like JRtI was down for repairs, causing the "dry run" ASDS landing.

Or else my theory of a week ago was correct, ad this did have a bunch of fancy mass-y new recovery gear... but it didn't work right.

Maybe we'll get some word from SpaceX, maybe we'll never know.

That's my guess too, doing everything except catching the fairing.
Title: Re: Fairing reuse
Post by: octavo on 12/26/2017 05:03 am
I haven't seen this posted here yet: on the SpaceX FB group Pauline Acalin posted a pic of Mr. Steven in Port with rigging across those 4 arms. What can the detectives here sleuth from this?

Link to FB thread where image appears:
https://m.facebook.com/groups/2387776317?view=permalink&id=10156138270661318

ETA: Attached here directly, with permission from Pauline. (https://uploads.tapatalk-cdn.com/20171226/115188ad08a69ba351cc68a7cc26ad3f.jpg)
There is a set of lines that run from arm to arm, forming a square at the start of the top, straight section of the arms. There appear to be two guylines running from the two aft arms down to the deck. I don't see the same lines on the fore arms.

The central platform the 4 arms connect to looks big enough for a fairing.
Title: Re: Fairing reuse
Post by: BeamRider on 12/26/2017 05:23 am
What could work would a vertically-oriented bouncy castle (VBC) “wall” amidships, plus a horizontally-oriented BC (HBC) on each outrigger. Outriggers lay out nearly flat on water surface for capture. After a fairing is dropped on an HBC by a steerable parachute, outrigger is lifted and fairing slides or rolls against VBC. Outrigger goes nearly vertical to grip fairing in place between VBC and HBC. Rinse, repeat.
Title: Re: Fairing reuse
Post by: john smith 19 on 12/26/2017 06:21 am
What could work would a vertically-oriented bouncy castle (VBC) “wall” amidships, plus a horizontally-oriented BC (HBC) on each outrigger. Outriggers lay out nearly flat on water surface for capture. After a fairing is dropped on an HBC by a steerable parachute, outrigger is lifted and fairing slides or rolls against VBC. Outrigger goes nearly vertical to grip fairing in place between VBC and HBC. Rinse, repeat.
So you're thinking these are the support arms for a set of "bouncy castle walls" that funnel the faring(s) into the centre?
Title: Re: Fairing reuse
Post by: octavo on 12/26/2017 08:10 am
Line the walls and floor with bouncy castle walls. Parafoil releases the fairing right over the  funnel, allowing it to fall onto the bouncy floor. (https://uploads.tapatalk-cdn.com/20171226/f528252ce0aabdfcded4cf5b31b3d09e.jpg)
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 12/26/2017 08:55 am
To me inflatable structures seem quite a bit more hassle to operate and maintain than appropriately tensioned nets. It’s not clear to me how significant the benefit(s) of using inflatables?
Title: Re: Fairing reuse
Post by: Cheapchips on 12/26/2017 09:00 am

As well as a castle, bouncy castles are a bit prone to winds. 

Nets are also common nautical fair!
Title: Re: Fairing reuse
Post by: meekGee on 12/26/2017 10:20 am
To me inflatable structures seem quite a bit more hassle to operate and maintain than appropriately tensioned nets. It’s not clear to me how significant the benefit(s) of using inflatables?
Agreed.  The four arm structure, to me, says "non elastic web".

If there's controlled give to it, it's created by controlling the tension in four cables coming down from pulleys at the apexes using brake winches.
Title: Re: Fairing reuse
Post by: Johnnyhinbos on 12/26/2017 10:55 am
One interesting point is NEC Quest ahead of her. She has a large A Frame davit on her stern and a fairing sized enclosure on her stern. Is she used for Dragon recovery ops?
Title: Re: Fairing reuse
Post by: BeamRider on 12/26/2017 11:52 am
So you're thinking these are the support arms for a set of "bouncy castle walls" that funnel the faring(s) into the centre?

Yes. A “net” approach (my first assumption too) has problem that I am trying to work around:
1. You cannot catch both fairings at once without potential interference.
2. You cannot catch both sequentially without potentially damaging contact of one fairing landing and laying on the other.
3. Any scheme for moving one out of the way or somehow protecting it, and then catching the other to avoid 2 will have to be completed very quickly. It’s hard to imagine the degree of control over the timing of the landing via alternate parachute paths, or Angle of Attack, exceeding a minute, but this is just a guess
Title: Re: Fairing reuse
Post by: meekGee on 12/26/2017 12:24 pm
So you're thinking these are the support arms for a set of "bouncy castle walls" that funnel the faring(s) into the centre?

Yes. A “net” approach (my first assumption too) has problem that I am trying to work around:
1. You cannot catch both fairings at once without potential interference.
2. You cannot catch both sequentially without potentially damaging contact of one fairing landing and laying on the other.
3. Any scheme for moving one out of the way or somehow protecting it, and then catching the other to avoid 2 will have to be completed very quickly. It’s hard to imagine the degree of control over the timing of the landing via alternate parachute paths, or Angle of Attack, exceeding a minute, but this is just a guess
My guess is two boats, but there is the possibility of buying a few minutes by opening the chutes at very different times.

Still though - a fairing is worth so much more than the amortized cost of the boat, so two boats makes more sense to me.
Title: Re: Fairing reuse
Post by: AncientU on 12/26/2017 12:27 pm
To me inflatable structures seem quite a bit more hassle to operate and maintain than appropriately tensioned nets. It’s not clear to me how significant the benefit(s) of using inflatables?
Agreed.  The four arm structure, to me, says "non elastic web".

If there's controlled give to it, it's created by controlling the tension in four cables coming down from pulleys at the apexes using brake winches.

Looking closely at the ship rigging, it could be that the port pair and the starboard pair deploy 'bouncy castles' to their respective sides of the ship.  The forward arms look to be articulated in the lower section (shown straight in the image) and the aft arms look like they have a brace on deck for them to rest on when lowered past horizontal outboard.  This would create a pair of landing beds nicely separated by the width of the ship.

https://forum.nasaspaceflight.com/index.php?topic=37727.1020
Title: Re: Fairing reuse
Post by: meekGee on 12/26/2017 12:30 pm
To me inflatable structures seem quite a bit more hassle to operate and maintain than appropriately tensioned nets. It’s not clear to me how significant the benefit(s) of using inflatables?
Agreed.  The four arm structure, to me, says "non elastic web".

If there's controlled give to it, it's created by controlling the tension in four cables coming down from pulleys at the apexes using brake winches.

Looking closely at the ship rigging, it could be that the port pair and the starboard pair deploy 'bouncy castles' to their respective sides of the ship.  The forward arms look to be articulated in the lower section (shown straight in the image) and the aft arms look like they have a brace on deck for them to rest on when lowered past horizontal outboard.  This would create a pair of landing beds nicely separated by the width of the ship.

https://forum.nasaspaceflight.com/index.php?topic=37727.1020

That's interesting, hadn't thought of that.

EDIT:  But on further reflection and inspection of the image, I'm sticking with my original theory:

- Fixed arms.
- Inelastic web + pulleys, controlled sag via tension rope and brake pulley.
- Parachute system overtakes the ship, intersects its path, and "misses high".
- Parachute system drops the fairing-half into the net.
- OBPFH.
Title: Re: Fairing reuse
Post by: JamesH65 on 12/26/2017 01:11 pm
I like the bouncing castle/net chute idea. First fairing lands, slides down the chute, grabbed/slides on to dolly at bottom and moved out of the way. Second lands (easily delayed by an earlier parachute opening and/or a different number of parachutes.) and slides down to join the first.

Or how about two chutes on the net, and you just cover the first one once the first fairing has arrived, so the second slides down the second one.

I suspect there are a number of ways of arranging capture of two fairing with one boat.

Title: Re: Fairing reuse
Post by: alang on 12/26/2017 02:35 pm
If you were designing a general purpose cradle landing structure that could also be used for dragon capsules as well as fairings then could this be it? I could imagine the attempt being made for the cargo version. I'm assuming that avoiding salt water might be a good thing, even for something designed for it.
Title: Re: Fairing reuse
Post by: octavo on 12/26/2017 04:24 pm
If you were designing a general purpose cradle landing structure that could also be used for dragon capsules as well as fairings then could this be it? I could imagine the attempt being made for the cargo version. I'm assuming that avoiding salt water might be a good thing, even for something designed for it.
Not unless they changed the round parachutes currently used, for steerable parafoils.

With round chutes, steering control is very limited, making a precise landing nearly impossible.

ETA: how much do fairings weigh compared to a returning dragon? Probably the bouncy bag would have to be yuuuge to handle dragon too.
Title: Re: Fairing reuse
Post by: IanThePineapple on 12/26/2017 04:26 pm
If you were designing a general purpose cradle landing structure that could also be used for dragon capsules as well as fairings then could this be it? I could imagine the attempt being made for the cargo version. I'm assuming that avoiding salt water might be a good thing, even for something designed for it.

Landing a Dragon on a dry net would probably be super helpful, the heat shield and the many Dracos would be in much greater condition than they would be in saltwater.
Title: Re: Fairing reuse
Post by: Kansan52 on 12/26/2017 04:37 pm
Wamore was used on the Stig B and nearly landed on the launch site:

https://www.youtube.com/watch?v=UV7zL07Tof8
Title: Re: Fairing reuse
Post by: Lar on 12/26/2017 04:44 pm
Landing a Dragon on a dry net would probably be super helpful, the heat shield and the many Dracos would be in much greater condition than they would be in saltwater.
Would the netting material need to be heat resistant? Does the heat shield have sufficient time (the airflow presumably is good) to cool down? What about the thruster ports? (if not fired, then presumably yes?)
Title: Re: Fairing reuse
Post by: octavo on 12/26/2017 05:08 pm
Landing a Dragon on a dry net would probably be super helpful, the heat shield and the many Dracos would be in much greater condition than they would be in saltwater.
Would the netting material need to be heat resistant? Does the heat shield have sufficient time (the airflow presumably is good) to cool down? What about the thruster ports? (if not fired, then presumably yes?)
Would several minutes under a parachute be enough? The heat of reentry is intense, but relatively short duration.
Title: Re: Fairing reuse
Post by: rberry on 12/27/2017 06:08 am
Mr. Steven is a relatively fast moving vessel for its size. If you attach any number of large bouncy castles to the rear of the vessel (in the water or suspended in the air), then she won't be able to utilize her speed due to the increased drag. At that point it would be cheaper to use a slower moving vessel of the same size. Whatever is suspended from the masts will likely not inhibit the vessels speed (its primary asset over other vessels). Something net like.
Title: Re: Fairing reuse
Post by: john smith 19 on 12/27/2017 08:16 am
Would several minutes under a parachute be enough? The heat of reentry is intense, but relatively short duration.
IIRC one of the attractions of PICA is it's both quite low density and a poor thermal conductor. This means
a) The reentry heat stays in a layer near the surface and
b) There is (relatively) less of it than with older ablators.

Treat the heat as a fluid and PICA like a sponge. Several minutes falling through fairly dense, cold air below M1 should certainly "evaporate" the heat from the surface layer. The remaining heat (deeper below the surface) will then split. Some diffuses inwards, some back to the surface.

Exactly how long that process lasts, how many Joules need to be shed and what the surface temp of the heatshield will be when it hits the nets/inflated walls are why you run FEA software.
Title: Re: Fairing reuse
Post by: Lar on 12/27/2017 11:55 am
This thread asked what the specific heat of PICA-X was, I don't think an answer was ever found.
https://forum.nasaspaceflight.com/index.php?topic=36039.0

I would suspect it was rather high but?

( High specific heat means more heat energy is needed per unit mass to raise the temperature of a material by one degree so it makes a better defense against heat energy. If the thermal conductivity is low that's a good thing too (while defending). This is a place where low density kind of works against you on heating up, but for you on cooling down again. Same with thermal conductivity... low works for you on heating and against you on cooling)
Title: Re: Fairing reuse
Post by: speedevil on 12/27/2017 01:37 pm
Mr. Steven is a relatively fast moving vessel for its size. If you attach any number of large bouncy castles to the rear of the vessel (in the water or suspended in the air), then she won't be able to utilize her speed due to the increased drag

Umm...
From the specs (http://www.seatranmarine.com/vessels-1/mr-steven) Mr Steven has 10000hp - 7.2MW.
It can cruise at 16m/s.
This implies a drag of around 450000N.
At this airspeed, one square meter has about 150N of drag, worst case.
So, a 17 meter square sail, with its maximum area pointed at the wind will absorb a power equal to one tenth of the water drag.

This is quite a lot - the arms on the ship are ~25m from each other, even a ~5m*25m frontal area bouncy castle on top of the arms, with a hemicylindrical front will impact the speed by under 10%.
Title: Re: Fairing reuse
Post by: JAFO on 12/27/2017 05:26 pm
What about rebound? Even if it's moving slowly, something that big is going to land with a lot of energy, is there enough room to absorb it all or how could they keep the fairing from impacting and not bouncing off?

Title: Re: Fairing reuse
Post by: speedevil on 12/27/2017 05:35 pm
What about rebound? Even if it's moving slowly, something that big is going to land with a lot of energy, is there enough room to absorb it all or how could they keep the fairing from impacting and not bouncing off?

This is pretty much a solved problem for people that work with ropes.
You don't have the net supported by elastic ropes, but comparatively rigid ones, and you have either a rope connected to a clutch that allows it to slip in one direction at a high controlled force (so, say if >10 tons, it will slip), but not return. Or a 'rip' mechanism that takes lots of energy to rip and stops the bounce.
(https://i.imgur.com/DfOvDB1m.png) is an example of a strap for fall arrest - this has two wide straps that are sewn together - ripping the stitches absorbs lots of energy, but it doesn't cause a bounce like elastic would.
Title: Re: Fairing reuse
Post by: nacnud on 12/27/2017 06:30 pm
That is not reusable though, better to use the types of ropes used in climbing. In those the core of the rope is heat treated to make it crinkly. If a force is applied then the crinkles unfold to allow the rope to stretch. The normal ammount of stretch is 10% but it can be 30% or more. There is zero rebound.

In climbing the device described above is referred to as a screamer, it's used in situations where above a fixed amount of force the whole system would fail.

To catch a falling fairing I'd make a net out of dynamic rope (climbing rope) attached to the arms (as on Mr Stephens) with screamers. In normal operation the net alone would provide all the cushioning needed. In extreme situations the screamers would be triggered to protect the arms from failing but still allowing the fairing to be captured.
Title: Re: Fairing reuse
Post by: meekGee on 12/27/2017 07:49 pm
That is not reusable though, better to use the types of ropes used in climbing. In those the core of the rope is heat treated to make it crinkly. If a force is applied then the crinkles unfold to allow the rope to stretch. The normal ammount of stretch is 10% but it can be 30% or more. There is zero rebound.

In climbing the device described above is referred to as a screamer, it's used in situations where above a fixed amount of force the whole system would fail.

To catch a falling fairing I'd make a net out of dynamic rope (climbing rope) attached to the arms (as on Mr Stephens) with screamers. In normal operation the net alone would provide all the cushioning needed. In extreme situations the screamers would be triggered to protect the arms from failing but still allowing the fairing to be captured.


Yup - the equivalent of the crush cores at end-of-travel for the landing legs on F9.

If the braking winch is electric, you actually have a record of how gently the fairing was caught, what was the maximum g on it, etc.  Crossing a certain limit would trigger a more detailed post-catch inspection.  (or actually any form of strain gauge would do)
Title: Re: Fairing reuse
Post by: speedevil on 12/28/2017 11:32 am

If the braking winch is electric, you actually have a record of how gently the fairing was caught, what was the maximum g on it, etc.  Crossing a certain limit would trigger a more detailed post-catch inspection.  (or actually any form of strain gauge would do)

Electric also lets you do things like vary the braking force so that per line it is a maximum of 30 tons, but the total is capped at 60 tons.
Or more advanced schemes aimed at catching it properly - for example, if it lands too far forward, you may want to slack off the back of the net almost entirely to avoid it being tipped out as the front drops.
Title: Re: Fairing reuse
Post by: meekGee on 12/28/2017 11:37 am
Yup, exactly.
Title: Re: Fairing reuse
Post by: AncientU on 12/28/2017 11:44 am
So, what colors are the balls going to be? ;)
Title: Re: Fairing reuse
Post by: Basto on 12/28/2017 03:39 pm
What if the “bouncy castle” is just down on the deck and the line running across between the arms are meant to snag the parachute lines and then they drop tension on the lines and drop the fairing quickly onto the bouncy castle. That way the first line is out of the way when the second fairing half comes in and they repeat the process.
Title: Re: Fairing reuse
Post by: meekGee on 12/28/2017 03:52 pm
What if the “bouncy castle” is just down on the deck and the line running across between the arms are meant to snag the parachute lines and then they drop tension on the lines and drop the fairing quickly onto the bouncy castle. That way the first line is out of the way when the second fairing half comes in and they repeat the process.
Hmmm...  That's interesting too... 

The parachute system will then overtake the boat, flaring so that it flies horizontally, and intersect the wire.

I like any system that only requires an intersection of paths, not a bulls eye.  Leaves one DOF open for last minute corrections.

In your case  the fairing and its harness might just stay hung...
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 12/28/2017 05:14 pm
Quote
@NASASpaceflight Pics of Mr. Steven taken on the 24th by me, feel free to use em where ever :) ~6 hours after arrival into port, there were some workers around, but no fairing to be seen.

https://twitter.com/angrypackomeese/status/946431406825025536
Title: Re: Fairing reuse
Post by: Oersted on 12/28/2017 07:36 pm
I really doubt there will be any substantial "bouncy castle". Doesn't go well with the wind forces often encountered at sea. Count me in the "net" camp! (former navy guy)
Title: Re: Fairing reuse
Post by: octavo on 12/29/2017 04:20 am
Net or bouncy castle, I think the funnel shape I drew earlier (very poorly) is still correct. I wonder why there are pulleys only from the top of the aft arms. I would guess they have to do with dropping the floor net onto the deck, perhaps to prepare for catching the second fairing.
Title: Re: Fairing reuse
Post by: Cheapchips on 12/29/2017 01:12 pm

Apologies if I missed it somewhere in the thread - what time gap is possible between fairing landings?  They can presumably deploy at different altitude and have other options for varying glide range?
Title: Re: Fairing reuse
Post by: nacnud on 12/29/2017 01:18 pm
I don't think anyone has run the numbers, you could give it a try and see what might be reasonable.
Title: Re: Fairing reuse
Post by: Cheapchips on 12/29/2017 01:41 pm
I don't think anyone has run the numbers, you could give it a try and see what might be reasonable.

I'd love to.  Not remotely within my skillset though!
Title: Re: Fairing reuse
Post by: nacnud on 12/29/2017 01:52 pm
https://skydivehigh.com/skydive-high/haho-intro/

A quick google gives a canopy time of 20 mins for a high altitude high opening parachute jump, so you could get 15 minutes between the fairings, provided you can design a parachute system that can open that high.
Title: Re: Fairing reuse
Post by: Cheapchips on 12/29/2017 02:21 pm
Well, a quick Google is within my skillset, just wasn't sure of that was providing the necessary depth of response. :)

15 minutes seems like a pretty short window to reset for the 2nd faring half, if a re-rigging of Mr Steven's grabber was required.

Did come across a brief bit of info that a Rogallo wing was considered and tested for 60's NASA capsules.  Without having chance to delve further atm, I thought some images were interesting:

link (https://www.google.co.uk/search?q=Rogallo+wing+apollo&rls=com.microsoft:en-GB:IE-Address&dcr=0&tbm=isch&source=iu&ictx=1&fir=Vm7CTbVRkMewtM%253A%252CtIrnIEzd7BzyaM%252C_&usg=__hTC7cP0TqOVc7f3JfsGV_m9cKBk%3D&sa=X&ved=0ahUKEwj6srurwq_YAhXREewKHfIDARgQ9QEIOzAD#imgrc=_&spf=1514560962262)




Title: Re: Fairing reuse
Post by: Johnnyhinbos on 12/29/2017 02:30 pm
Personally I doubt they would do a high altitude opening (I have a Class A jump certification, but am certainly no authority).

Upper level wind is pretty high and often contrary to lowers. This leads to a loss of precision in the landing zone, even when using a steerable chute. Additionally, high altitudes in turn give low air density which in turn require larger strokes over longer times to effect control authority over the wing. Low density deployment also leads to higher spring recoil where the parachute can momentarily have a higher descent velocity than the payload.

Point being, I’d guess a later opening to pick up denser air with less variables re wind speed and direction.
Title: Re: Fairing reuse
Post by: nacnud on 12/29/2017 02:37 pm
Google is a nice place to start before breaking out the physics, :)

I think a ram air chute is more likely than a Rogallo wing these days, like that used with the X38.

As for the 15 mins between faring landings I think it's feasible but you'd want to try and avoid too much labour on deck between landings. I'm imagining something like
1) Catch fairing in net
2) Deal with parachute (I like the idea of the magic disappearing curtain from the Dragon 2 reveal (https://www.youtube.com/watch?v=yEQrmDoIRO8?t=3m31s), start at 3:30)
3) Lower fairing to deck and temporarily secure
4) Reset net, it could be the same net but using a different one might be easier
5) Repeat.
Title: Re: Fairing reuse
Post by: nacnud on 12/29/2017 02:42 pm
Personally I doubt they would do a high altitude opening...

Me too but I was trying to find an upper boundary for possible time between fairings, what would you suggest? 5 mins?
Title: Re: Fairing reuse
Post by: Johnnyhinbos on 12/29/2017 02:51 pm
Personally I doubt they would do a high altitude opening...

Me too but I was trying to find an upper boundary for possible time between fairings, what would you suggest? 5 mins?
I think perhaps they might open around the same time but follow different plight profiles to dump altitude as needed.

Generally speaking however - I think this entire endeavor is amazing. It's a really tricky problem and I love that SpaceX is actively tackling it!
Title: Re: Fairing reuse
Post by: john smith 19 on 12/29/2017 06:14 pm
This thread asked what the specific heat of PICA-X was, I don't think an answer was ever found.
https://forum.nasaspaceflight.com/index.php?topic=36039.0

I would suspect it was rather high but?

( High specific heat means more heat energy is needed per unit mass to raise the temperature of a material by one degree so it makes a better defense against heat energy. If the thermal conductivity is low that's a good thing too (while defending). This is a place where low density kind of works against you on heating up, but for you on cooling down again. Same with thermal conductivity... low works for you on heating and against you on cooling)
The balance in the process is quite subtle. Lower density --> Lower SHC but Lower density --> poorer thermal conductor (Historically AVCOAT was quite a good conductor and was about 2x heavier than 1st generation PICAX).

AFAIK the parameter that brings things together is known as the "Thermal Diffusivity" and is loosely described as  measure of how heat spreads through a material, where things like SHC tend to be bulk properties, assuming the whole thing is at a certain temperature, or thermal conductivity, which assumes a constant temperature gradient.

But that about exhausts my HS level physics.
Title: Re: Fairing reuse
Post by: Steve D on 12/30/2017 01:31 am
My money is on them eventually having 2 boats out there. Just catching 1 fairing half during the test phase then setting up a second ship when they go into normal recovery operations. KISS principle at work
Title: Re: Fairing reuse
Post by: ClayJar on 12/30/2017 03:22 am
My money is on them eventually having 2 boats out there. Just catching 1 fairing half during the test phase then setting up a second ship when they go into normal recovery operations. KISS principle at work

Two boats seems the pragmatic approach.  I'm not sure I'd want to bet $5 million on everything going right without any glitches.  (Or would that be $2.5 million, since you'd only have to wave goodbye to the second half?)

If I were trying to find ways to make things more efficient, the first thing I'd have to wonder is whether I can consolidate something *other* than fairing catching.  Can I, perhaps, get a fairing catcher that can also tow an ASDS into position?  Saves me the same number of boats, but doesn't require perfect timing.  (Not saying a fairing catcher can be a ASDS towing craft, but you get the general idea.)
Title: Re: Fairing reuse
Post by: deruch on 12/30/2017 07:02 am
My money is on them eventually having 2 boats out there. Just catching 1 fairing half during the test phase then setting up a second ship when they go into normal recovery operations. KISS principle at work

Two boats seems the pragmatic approach.  I'm not sure I'd want to bet $5 million on everything going right without any glitches.  (Or would that be $2.5 million, since you'd only have to wave goodbye to the second half?)

If I were trying to find ways to make things more efficient, the first thing I'd have to wonder is whether I can consolidate something *other* than fairing catching.  Can I, perhaps, get a fairing catcher that can also tow an ASDS into position?  Saves me the same number of boats, but doesn't require perfect timing.  (Not saying a fairing catcher can be a ASDS towing craft, but you get the general idea.)

It may be wrong that both fairing halves are equally valued.  The active half may be worth significantly more.  IMO, the best argument for investing the effort to catch the fairings at all is that it saves the large capital expenditures needed to make a whole lot more fairings, and thereby enables SpaceX's goal of a much higher flight rate.  Catching just 1 could be enough to meet their short term needs and so we won't see anything else until they start getting closer to their limiting rate.
Title: Re: Fairing reuse
Post by: AncientU on 12/30/2017 01:01 pm
My money is on them eventually having 2 boats out there. Just catching 1 fairing half during the test phase then setting up a second ship when they go into normal recovery operations. KISS principle at work

Two boats seems the pragmatic approach.  I'm not sure I'd want to bet $5 million on everything going right without any glitches.  (Or would that be $2.5 million, since you'd only have to wave goodbye to the second half?)

If I were trying to find ways to make things more efficient, the first thing I'd have to wonder is whether I can consolidate something *other* than fairing catching.  Can I, perhaps, get a fairing catcher that can also tow an ASDS into position?  Saves me the same number of boats, but doesn't require perfect timing.  (Not saying a fairing catcher can be a ASDS towing craft, but you get the general idea.)

It may be wrong that both fairing halves are equally valued.  The active half may be worth significantly more.  IMO, the best argument for investing the effort to catch the fairings at all is that it saves the large capital expenditures needed to make a whole lot more fairings, and thereby enables SpaceX's goal of a much higher flight rate.  Catching just 1 could be enough to meet their short term needs and so we won't see anything else until they start getting closer to their limiting rate.

The rig looks heavy enough to catch a second stage... just sayin'
Title: Re: Fairing reuse
Post by: Steve D on 12/30/2017 02:29 pm
My money is on them eventually having 2 boats out there. Just catching 1 fairing half during the test phase then setting up a second ship when they go into normal recovery operations. KISS principle at work

Two boats seems the pragmatic approach.  I'm not sure I'd want to bet $5 million on everything going right without any glitches.  (Or would that be $2.5 million, since you'd only have to wave goodbye to the second half?)

If I were trying to find ways to make things more efficient, the first thing I'd have to wonder is whether I can consolidate something *other* than fairing catching.  Can I, perhaps, get a fairing catcher that can also tow an ASDS into position?  Saves me the same number of boats, but doesn't require perfect timing.  (Not saying a fairing catcher can be a ASDS towing craft, but you get the general idea.)


I think the requirements of the fairing catching ship and a tug boat are too different to be able to do both. The catcher need to be fast and maneuverable, the tug needs  to be a high "torque" kind of powerful. Its the difference between a sports car and a bulldozer. You dont pull a trailer with a corvette, you dont run around town in a bulldozer. 
Title: Re: Fairing reuse
Post by: corrodedNut on 12/30/2017 08:48 pm
I'm thinking it's something like this:

https://youtu.be/6qF_fzEI4wU?t=1m
Title: Re: Fairing reuse
Post by: meekGee on 12/30/2017 09:06 pm
I'm thinking it's something like this:

https://www.youtube.com/watch?v=6qF_fzEI4wU?t=1m

Yup - that's the "Except one guy" I referred to up thread...   Isn't it the craziest, yet actually most well-controlled stunts there ever was?

I mean - you can argue it was actually safer than a parachute jump since he didn't even have to worry about a parachute malfunction...  It was already open, only he wasn't wearing it yet  :)

Can't watch it without laughing out loud, but that's the kind of thinking of why I think the parachute will cut loose from the fairing before being caught.
Title: Re: Fairing reuse
Post by: OxCartMark on 12/31/2017 02:01 am
There is another way that a net or other catcher could be rigged on those four masts though not likely.  A smaller net could be suspended by four lines from the posts or from rigging on the perimeter line and controlled by multiple servo winches so that the net would be rapidly moved as needed to catch the fairing half.  Similar to the mobile TV cameras that are suspended above football fields.  Perhaps such a setup could be used without a net to connect with feature(s) on the fairing.  What is the benefit to such a system over a simple large net?  Only one I can think of - the ability to catch a fairing half and quickly manipulate it off to the side and ready itself for a second catch.  Do I think this is what they are doing?  No.  Primarily because those fairing halves are really stinking large (ref. Roadster image) and the area defined by the four masts can't be that much larger.  Secondarily the rigging of the lines on the four masts looks too basic, too low tech for that.

Personally I doubt they would do a high altitude opening (I have a Class A jump certification, but am certainly no authority).

Upper level wind is pretty high and often contrary to lowers. This leads to a loss of precision in the landing zone, even when using a steerable chute. Additionally, high altitudes in turn give low air density which in turn require larger strokes over longer times to effect control authority over the wing. Low density deployment also leads to higher spring recoil where the parachute can momentarily have a higher descent velocity than the payload.

Point being, I’d guess a later opening to pick up denser air with less variables re wind speed and direction.
The effects of high altitude wind could be mitigated (mostly) if Mr. Steven threw out a few weather balloons to determine what's up.  Back in the 70s I made a thing of predicting the landing spot of model rockets.  When there was significant wind and we were expecting a high flight I would often put up a kite.  You can look up a kite line and see how the wind bows it at various levels.

Low density deployment also leads to higher spring recoil where the parachute can momentarily have a higher descent velocity than the payload.

OT: That phenomenon is even more pronounced when a paraglider wing opens after being wadded up and falling for a bit - it can shoot forward and down so vigorously that it can end up under its pilot.  The pilot can than fall into and become wrapped up in his own wing which is never really a good thing.

My money is on them eventually having 2 boats out there. Just catching 1 fairing half during the test phase then setting up a second ship when they go into normal recovery operations. KISS principle at work
Unlikely but possible alternate scenario: Fabricate a light weight high speed hull to use as a trailer behind the main high speed ship.  Light enough to maintain speed, same cross section profile, same catch area, unmanned.


I think the parachute will cut loose from the fairing before being caught.
Ya gotta get rid of it as soon as you're in the net there isn't much of a way around that, you're only a few knots below the speed at which the lift of the chute would exceed the weight of the fairing (in which case the fairing would briefly be able to maintain level flight and possibly ascend a bit - until contact with the net were to be broken which would remove the horizontal propelling force.  Even below flying speed there is very little normal force on the net to allow sufficient friction force to keep the fairing from sliding out the back of the net.  Very similar to kiting a paraglider in high winds where you may only have a few single digit pounds of weight on your feet with which to try to maintain an adequate forward force for your weight and L/D.
Title: Re: Fairing reuse
Post by: john smith 19 on 12/31/2017 08:43 am
Personally I doubt they would do a high altitude opening (I have a Class A jump certification, but am certainly no authority).

Upper level wind is pretty high and often contrary to lowers. This leads to a loss of precision in the landing zone, even when using a steerable chute. Additionally, high altitudes in turn give low air density which in turn require larger strokes over longer times to effect control authority over the wing. Low density deployment also leads to higher spring recoil where the parachute can momentarily have a higher descent velocity than the payload.

Point being, I’d guess a later opening to pick up denser air with less variables re wind speed and direction.
The effects of high altitude wind could be mitigated (mostly) if Mr. Steven threw out a few weather balloons to determine what's up.  Back in the 70s I made a thing of predicting the landing spot of model rockets.  When there was significant wind and we were expecting a high flight I would often put up a kite.  You can look up a kite line and see how the wind bows it at various levels.
IIRC high altitude winds scrubbed a number of Shuttle launches and landings, presumably because they exceeded the pre loaded parameters in the GNC software.

Toward the end of the programme they were starting to use radar "sounders" to do wind profile measurements. They seemed to do this at 30 min intervals up to launch but I was never sure if this was because the processing was so complex or that was just what they were set up for. IIRC they were quite long wave systems, in the 10s, not 100s of MHz.  LIDAR would also be an option. I'd guess they would be most useful in putting the recovery vessel in a more optimal location, reducing motion of it or the parachutes.
Title: Re: Fairing reuse
Post by: Oersted on 12/31/2017 05:46 pm
The rig looks heavy enough to catch a second stage... just sayin'

Or a Dragon 2?
Title: Re: Fairing reuse
Post by: yokem55 on 12/31/2017 08:08 pm
The rig looks heavy enough to catch a second stage... just sayin'

Or a Dragon 2?
Or other folks might want to catch an engine compartment from a booster...
Title: Re: Fairing reuse
Post by: brainbit on 01/05/2018 09:42 pm
I think they are only practicing to catch a dragon 2, since they dropped the Draco power decent they have a problem with re-use if the dragon 2 drops in the sea. If they can catch the dragon 2 before it lands in the water it would be much cheaper to re-use. This is why they only need one catchers mitt. And why they are practicing with the fairings.   
Title: Re: Fairing reuse
Post by: Tomness on 01/06/2018 12:33 am
The rig looks heavy enough to catch a second stage... just sayin'

Or a Dragon 2?
Or other folks might want to catch an engine compartment from a booster...



Can I pull a Jim say No?.... b/c do you know how heavy Dragon is?, apples to oranges of recovery of catching fairings vs catching a dragon... feather vs dumb bell.


Title: Re: Fairing reuse
Post by: JamesH65 on 01/07/2018 10:03 am
The rig looks heavy enough to catch a second stage... just sayin'

Or a Dragon 2?
Or other folks might want to catch an engine compartment from a booster...



Can I pull a Jim say No?.... b/c do you know how heavy Dragon is?, apples to oranges of recovery of catching fairings vs catching a dragon... feather vs dumb bell.

Although the net arms on that boat appear massively engineered to just to catch that feather of a fairing..
Title: Re: Fairing reuse
Post by: Hobbes-22 on 01/07/2018 10:38 am
That's a side effect of arm length. Supporting 1 ton at 10 meters out means the base of the arm needs to withstand 10 ton-meter. And you don't want the arms to go TWANGGGG when the fairing hits.
Title: Re: Fairing reuse
Post by: rsdavis9 on 01/07/2018 01:08 pm
So what is the weight of a fairing? 1 ton?
Dragon 2 is 6.4t dry and 2.5t return payload so 9t.
Title: Re: Fairing reuse
Post by: Alastor on 01/07/2018 01:24 pm
SpaceX has been saying for quite a long time that they initially had more issues than expected with salt water ingressing the dragons system, which complicated a lot the refurbisment.
They also have been very public about the fact that they have been working on that problem so that they can continue operations as initially planned without having to essentially wipe out everything but the pressure vessel during refurbishment operations.
SpaceX has also been public about the fact that they DO intend to recover fairings and that they are working on it.

In a nutshell, fairing recovery operations are not a rehearsal or a preparation step for dragon recovery operations and I think we should get back on topic.
Title: Re: Fairing reuse
Post by: the_other_Doug on 01/09/2018 09:55 pm
Any clues as to whether any attempt was made at recovering one or both of the fairings from Sunday's Zuma launch?
Title: Re: Fairing reuse
Post by: Tomness on 01/10/2018 07:13 am
Any clues as to whether any attempt was made at recovering one or both of the fairings from Sunday's Zuma launch?
That would be G-14 classified, that mission is so nuts, i wouldn't put it past them to pyro the fairings to make sure every trace has been removed. Better used on more benign campaign.
Title: Re: Fairing reuse
Post by: Alastor on 01/10/2018 08:37 am
Any clues as to whether any attempt was made at recovering one or both of the fairings from Sunday's Zuma launch?

I have seen video evidence of fairing detachment (SpaceLaunchReport video), but I have seen no sign of RCS firing.
Of course this does not mean that the fairing seen in there would be the active one. This does not mean either that RCS firing would necessarily be seen in this video, nor that RCS firing would happen while the fairing is visible (though based on past experience, I expect it would happen).

Another element is that the spaceX ships do not seem to have been on location for recovery ops.

Finally they already had issues with fairing on Zuma and this is a highly classified highly valuable payload, so I expect they might not be very willing to experiment on that one (since something can always go wrong).

All of this leads me to say that there probably wasn't any fairing recovery ops with this launch.
Title: Re: Fairing reuse
Post by: Jarnis on 01/10/2018 11:42 am
Cold Gas RCS firings with the fairings are visible only during dusk/dawn launches or really clear sky day launches.

Late night launch like Zuma, no way to see them. Heck, the fairings themselves were only barely visible in the amateur footage.
Title: Re: Fairing reuse
Post by: Alastor on 01/10/2018 11:52 am
I'm not certain they couldn't be illuminated by plume interaction, when close to the booster. But I agree, they probably wouldn't be seen given the illumination conditions.
Title: Re: Fairing reuse
Post by: Dave G on 01/13/2018 09:49 am
Does anyone know if SpaceX plans to recover the Falcon Heavy fairing ?

Also, what ever happened to the fairing they recovered from SES-10 ?
Title: Re: Fairing reuse
Post by: ZachS09 on 01/15/2018 01:00 am
Does anyone know if SpaceX plans to recover the Falcon Heavy fairing ?

Also, what ever happened to the fairing they recovered from SES-10 ?

#1: Right now, there's no plan to recover the FH Demo fairings, but that possibility can arise at the last minute.

#2: Yes, one of the SES-10 fairings was found intact, but not recovered for reuse.
Title: Re: Fairing reuse
Post by: meekGee on 01/15/2018 02:25 am
Well Mr. Steven is still in LA, FWIW.
Title: Re: Fairing reuse
Post by: Alastor on 01/15/2018 08:21 am
Well Mr. Steven is still in LA, FWIW.

How long did he take to cross last time ?
We're still a fair way left of launch date.
There's also the possibility that they already started to outfit an other ship we don't know about yet, since it seems their fleet is currently being reshufled quite a bit (although I wouldn't bet on that hypothesis. I think it's much better to do 1 ship, test, redo if necessary, and then do the other ships you need using the lessons learned from the first one).
Title: Re: Fairing reuse
Post by: meekGee on 01/15/2018 08:49 am
Well Mr. Steven is still in LA, FWIW.

How long did he take to cross last time ?
We're still a fair way left of launch date.
There's also the possibility that they already started to outfit an other ship we don't know about yet, since it seems their fleet is currently being reshufled quite a bit (although I wouldn't bet on that hypothesis. I think it's much better to do 1 ship, test, redo if necessary, and then do the other ships you need using the lessons learned from the first one).
Hence the FWIW...
Title: Re: Fairing reuse
Post by: vanoord on 01/16/2018 02:31 pm
Does anyone know if SpaceX plans to recover the Falcon Heavy fairing ?


There should be plenty of space inside that fairing to put additional recovery hardware - and there's certainly spare weight capacity...
Title: Re: Fairing reuse
Post by: Lar on 01/16/2018 03:23 pm
Well Mr. Steven is still in LA, FWIW.

How long did he take to cross last time ? 

She. Ships are feminine. Even if given a masculine name. :)

I agree with the idea that only one set of recovery hardware will be built until much closer to the final configuration (there have been mods since the second ASDS was built/rebuilt but they have not been that extensive)
Title: Re: Fairing reuse
Post by: meekGee on 01/16/2018 03:44 pm
Well Mr. Steven is still in LA, FWIW.

How long did he take to cross last time ? 

She. Ships are feminine. Even if given a masculine name. :)

I agree with the idea that only one set of recovery hardware will be built until much closer to the final configuration (there have been mods since the second ASDS was built/rebuilt but they have not been that extensive)
My apologies to the lady.  The beard threw me off.
Title: Re: Fairing reuse
Post by: Hobbes-22 on 01/16/2018 04:40 pm

She. Ships are feminine. Even if given a masculine name. :)


True for English, not so much in other languages.
Title: Re: Fairing reuse
Post by: Lar on 01/16/2018 04:51 pm

She. Ships are feminine. Even if given a masculine name. :)


True for English, not so much in other languages.

This is a forum that is almost exclusively conducted in English. Hence my nitpick. 'nuff said.
Title: Re: Fairing reuse
Post by: darkenfast on 01/18/2018 04:04 am
Unfortunately, calling a ship a "she" in our Politically Correct U.S. Navy has been banned for some years. 

USN (Retired).
Title: Re: Fairing reuse
Post by: john smith 19 on 01/21/2018 09:20 am
Does anyone know if SpaceX plans to recover the Falcon Heavy fairing ?


There should be plenty of space inside that fairing to put additional recovery hardware - and there's certainly spare weight capacity...
An obvious question with fairings is whether you can regard they are a "booster" (13 units of weight growth to cause 1 unit of final payload loss) or an upper stage (1 unit of stage weight growth equals 1 unit of payload lost)?

If it's "booster" then you could probably put quite a bit of stuff on it. If it's like the upper stage you are much more constrained.

Although it's part of the upper stage it's separation early(ish) in the flight suggests its booster like in its mass growth properties.
Title: Re: Fairing reuse
Post by: speedevil on 01/21/2018 09:39 am
An obvious question with fairings is whether you can regard they are a "booster" (13 units of weight growth to cause 1 unit of final payload loss) or an upper stage (1 unit of stage weight growth equals 1 unit of payload lost)?

If it's "booster" then you could probably put quite a bit of stuff on it. If it's like the upper stage you are much more constrained.

Although it's part of the upper stage it's separation early(ish) in the flight suggests its booster like in its mass growth properties.
Fairing jettison is around a tenth of the way into the burn, of 49 tons or so, and the stage mass, neglecting fairing is perhaps 55 tons including payload.
If the fairing is 5 tons, it's ~10% of the mass at this point, for ~10% of the flight.
Naively, you can approximate this as 1% loss.
edit: math is hard.
Title: Re: Fairing reuse
Post by: john smith 19 on 01/21/2018 12:25 pm
An obvious question with fairings is whether you can regard they are a "booster" (13 units of weight growth to cause 1 unit of final payload loss) or an upper stage (1 unit of stage weight growth equals 1 unit of payload lost)?

If it's "booster" then you could probably put quite a bit of stuff on it. If it's like the upper stage you are much more constrained.

Although it's part of the upper stage it's separation early(ish) in the flight suggests its booster like in its mass growth properties.
Fairing jettison is around a tenth of the way into the burn, of 49 tons or so, and the stage mass, neglecting fairing is perhaps 55 tons including payload.
If the fairing is 5 tons, it's ~20% of the mass at this point, for ~10% of the flight.
Naively, you can approximate this as 2% loss.
Thanks for those numbers. On that basis it sounds a lot more like we're in booster territory, so you've got a a fair amount of mass you could hang on the fairing before you had trouble. Obviously (as usual) you like it to be as little as possible. Getting it and keeping it in the right attitude being key.
Title: Re: Fairing reuse
Post by: Lar on 01/21/2018 01:14 pm
I had assumed it was more of a hit than the booster but a lot less than the second stage since fairings are shed fairly early. But that it's a variable amount depending on the mission profile. (the earlier it is shed, (the more popup the trajectory), the less of a hit). That's just guesswork.
Title: Re: Fairing reuse
Post by: oldAtlas_Eguy on 01/21/2018 04:46 pm
I had assumed it was more of a hit than the booster but a lot less than the second stage since fairings are shed fairly early. But that it's a variable amount depending on the mission profile. (the earlier it is shed, (the more popup the trajectory), the less of a hit). That's just guesswork.
Using the rocket equations to give an estimate of about 8.5 for GTO and about 7.8 for a LEO.
Title: Re: Fairing reuse
Post by: john smith 19 on 01/21/2018 05:55 pm
I had assumed it was more of a hit than the booster but a lot less than the second stage since fairings are shed fairly early. But that it's a variable amount depending on the mission profile. (the earlier it is shed, (the more popup the trajectory), the less of a hit). That's just guesswork.
Using the rocket equations to give an estimate of about 8.5 for GTO and about 7.8 for a LEO.
I presume you mean the "exchange rate" of mass on the fairing Vs loss of payload.
those numbers look backward on that basis.
Title: Re: Fairing reuse
Post by: speedevil on 01/22/2018 01:32 am
I had assumed it was more of a hit than the booster but a lot less than the second stage since fairings are shed fairly early. But that it's a variable amount depending on the mission profile. (the earlier it is shed, (the more popup the trajectory), the less of a hit). That's just guesswork.
Using the rocket equations to give an estimate of about 8.5 for GTO and about 7.8 for a LEO.

My above estimations were of the order of magnitude correct, but I screwed up in using the total mass of the stage, and more careful calculations agree with the above.

The amount of fuel required is indeed under 1% of the whole stage mass, but of course that's the wrong figure, and the true hit per kilo of fairing is more like 120g than 10g.
Title: Re: Fairing reuse
Post by: AncientU on 01/22/2018 04:08 pm
This.

Quote
If you're wondering why people swoon over SpaceX, it's because they routinely dare crazy shit like this and keep at it until they succeed.
https://twitter.com/SciGuySpace/status/955484504759599104
Title: Re: Fairing reuse
Post by: kdhilliard on 01/22/2018 10:30 pm
Mr. Steven is headed for the Panama Canal. While the end destination is currently Belize, that's just to refuel. The end destination is likely Port Canaveral. Good chance of a fairing recovery attempt during the GovSat launch.

Edit: I don't think it can make the 30th. I did some math. :D Either the launch date has slipped and we don't know yet, or this is for another launch.

Did Mr. Steven (or other SpaceX related ships) stop for refueling in San Pedro, Belize on past transits?  Coincidentally, the area in the Los Angeles port that SpaceX uses is in San Pedro, California.  You don't think they just messed up the AIS destination field?

Edit: Mr. Steven is now back home, berthed in the East Channel, bow-on to NRC Quest, and the infobox is no longer showing "BZ SPR", but is giving departed US LAX 2018-01-22 14:30, arrrived US LAX 2018-01-22 18:06.  Given that the hover-over pop-up said (and still says) "Destination: SAN PEDRO CALI" all along, I wonder if it was an error coding the AIS or if it was a MarineTraffic bug.
Title: Re: Fairing reuse
Post by: Michael Baylor on 01/22/2018 11:06 pm
Yeah, it's not headed for the Panama Canal. MarineTraffic was WRONG WRONG WRONG lol. It's going to return to the Port of LA.
Title: Re: Fairing reuse
Post by: gongora on 01/23/2018 12:38 am
The time track on her way to LA from Florida:
Dec 22, 2017, 00:04 UTC LOS ANGELES, USA
Dec 03, 2017, 03:00 UTC MANZANILLO, MEXICO
Nov 28, 2017, 06:00 UTC BALBOA, PANAMA

So it takes around a month to get only to Panama.

Also on www.vesselfinder.com destination is SAN PEDRO CALI (actually it's the same destination on the marinetraffic site too if you just hover the pointer on the ship).

May be this is just a trial run?

Not really on-topic at this point, but it does not take a month for that ship to get from LA to Panama.  JRTI got towed from the Atlantic side of the Panama Canal to Long Beach in a month.  Mr. Stephen can move a lot faster.
Title: Re: Fairing reuse
Post by: Michael Baylor on 01/23/2018 04:32 pm
Looks like another test! Mr. Steven is heading out for the second time in less than 24 hours.

And no, it's not going to Belize.  ;D
Title: Re: Fairing reuse
Post by: ChrisC on 01/28/2018 05:09 pm
Worth crossposting here.  Click through to quoted post to see graphics:

INTERESTING!

SpaceX recovery support ships Go Quest and Go Searcher have left Port Canaveral.

Possible fairing recovery test!
Title: Re: Fairing reuse
Post by: drzerg on 01/30/2018 11:43 am
Do we know approximate weight of the fairing half? I only found some data on spaceflight101 and do not know how accurate is their value of 1.75 t (per half ?)
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 02/06/2018 06:26 am
From the transcript (https://gist.github.com/theinternetftw/189852a3081eed7f695b80f374b8a727) of Elon’s pre-FH demo launch press conference:

Quote
We are in the process of recovering the fairing, we're getting better and better at recovering the fairing. So we expect to recover the fairing and the booster, the first stage of Falcon 9.
Title: Re: Fairing reuse
Post by: cscott on 02/06/2018 02:51 pm
From the transcript (https://gist.github.com/theinternetftw/189852a3081eed7f695b80f374b8a727) of Elon’s pre-FH demo launch press conference:

Quote
We are in the process of recovering the fairing, we're getting better and better at recovering the fairing. So we expect to recover the fairing and the booster, the first stage of Falcon 9.
For context, I'm pretty sure he was talking about "long term". That is, he expects the fairing recovery method they are developing to be ultimately successful.  There wasn't (in my listening) any implication that a specific upcoming attempt was likely to be successful---or not successful! No specific mission was being referenced is what I'm saying.
Title: Re: Fairing reuse
Post by: babakm on 02/06/2018 04:10 pm
Cropped/enhanced portion of recent Elon Tweet with Falcon Heavy flight profile graphic.  Looks like a Mr. Steven-a-like rigs with nets (on Go Quest & Go Searcher?) will be on station.  The graphic doesn't show parachutes or two boats, but that's probably for simplicity's sake.

https://twitter.com/elonmusk/status/960915618865274880
Title: Re: Fairing reuse
Post by: Alastor on 02/06/2018 04:57 pm
This is a graph made by a NSF L2 member. Even though reposted by Elon, it means it's not necessarily 100% accurate.
Although this is probably a pretty accurate timeline of what they want a standard FH launch to look like, it's possible that some of these events won't happen during this launch.

I have no certainty about the fairing recovery and the payload separation events, in particular. These may not be planned to happen during this launch.
Title: Re: Fairing reuse
Post by: babakm on 02/06/2018 05:14 pm
This is a graph made by a NSF L2 member. Even though reposted by Elon, it means it's not necessarily 100% accurate.

Thanks.  Didn't know that.
Title: Re: Fairing reuse
Post by: cscott on 02/06/2018 07:07 pm
In particular, Go Searcher is currently sitting at the dock across from Fishlips in Port Canaveral, so is not likely to be going out fishing for fairings today.
Title: Re: Fairing reuse
Post by: speedevil on 02/07/2018 12:07 am
https://www.youtube.com/watch?v=F7mw2_pfcz4 - the post-launch conference for FH - talks about Fairing recovery also. 55:50

Lightly edited to remove stumbles.
Quote
I'm pretty sure we'll have fairing recovery in the next six months.
It turns out that you pop the chute on the fairing and you've got this giant awkward thing it tends to interfere with the air flow on the on the parachute and and miss.

Gets all twisty and and was low priority too. But we have fairing version two which is the really  important one that we want to recover, so even if we recovered fairing version one, we wouldn't be re-flying it in the future. Fairing two and recovery that's very important, and my guess is - next six months we figure out recovery.
We've got a special boat to catch the fairing, like a catcher's mitt. It's like a giant catchers mitt in boat form.
 It's gonna run around it can't catch the fairing.
Kinda fun.
I think you might be able to do the same thing with dragon so if NASA wants us to, we could try to catch dragon.
Made for the fairing, but it would work for dragon too.
Title: Re: Fairing reuse
Post by: First Mate Rummey on 02/07/2018 09:47 pm

Quote
But we have fairing version two which is the really  important one that we want to recover, so even if we recovered fairing version one, we wouldn't be re-flying it in the future. Fairing two and recovery that's very important, and my guess is - next six months we figure out recovery.

Do you have any more info about fairing version 2?
It will be part of block V?
Is it supposed to be more expensive to require recovery be "very important"?
Lighter?
Bigger?
Title: Re: Fairing reuse
Post by: speedevil on 02/08/2018 11:31 am
Do you have any more info about fairing version 2?
It will be part of block V?
Is it supposed to be more expensive to require recovery be "very important"?
Lighter?
Bigger?

The available info seems to imply it may go along with block V.
The bits of F9 that the fairing attaches to are more-or-less static and unchanged over all blocks, as I understand it.
It may well be more expensive, it's certainly newer. Lighter - well - possibly not - recovery hardware isn't air.

I don't think we've seen any reasonable speculation it would be bigger, and Elon did not mention this when he has mentioned much smaller differences in the above conference.

If the fairing is double the price, and you recover and refly nearly all of them, that's a real bargain.
Title: Re: Fairing reuse
Post by: Asteroza on 02/09/2018 06:17 am
Would a new fairing require requalification for EELV work?
Title: Re: Fairing reuse
Post by: First Mate Rummey on 02/09/2018 07:40 am
About fairing version 2, SpaceNews has a hint here:
“One of the limits of the Falcon 9 for the DoD missions was that they needed a longer fairing. The payload was too tall for the existing fairing,” he said. “I’m hoping Elon Musk has a longer fairing on the Falcon Heavy.”
http://spacenews.com/military-certification-the-next-big-test-for-falcon-heavy/
Title: Re: Fairing reuse
Post by: JonathanD on 02/09/2018 04:02 pm
Sorry if I missed this, but are they going to try to use one ship to try to catch two fairing halves?  That seems even more improbable!
Title: Re: Fairing reuse
Post by: speedevil on 02/09/2018 04:12 pm
Sorry if I missed this, but are they going to try to use one ship to try to catch two fairing halves?  That seems even more improbable!

It is not impossible.
However, it's also rather likely that they're simply waiting to see how recovery works, before seeing if they need another identical boat, or a bigger/faster boat, or ...

Boats and steel and ropes and nets are cheap.
Especially so when you can resell them for a large fraction of the purchase price.
Title: Re: Fairing reuse
Post by: wannamoonbase on 02/09/2018 04:25 pm
Sorry if I missed this, but are they going to try to use one ship to try to catch two fairing halves?  That seems even more improbable!

It is not impossible.
However, it's also rather likely that they're simply waiting to see how recovery works, before seeing if they need another identical boat, or a bigger/faster boat, or ...

Boats and steel and ropes and nets are cheap.
Especially so when you can resell them for a large fraction of the purchase price.

Compared to payload fairings yes they are.

I'd like to see the ASDS replaced with a custom built ship that is self propelled.  It should be able to return boosters to land faster than barges and tugs.   (Ideally a ship that could recover 1, stow it and recover another a day or two later.)

Catcher mitt style fairing recovery could be a very fast way to return them to shore.  Catch it, secure it and full throttle for port.  Hopefully they'll be able to get them protected from the elements after recovery.
Title: Re: Fairing reuse
Post by: speedevil on 02/12/2018 04:23 pm
Do you have any more info about fairing version 2?
It will be part of block V?
Is it supposed to be more expensive to require recovery be "very important"?
Lighter?
Bigger?

The available info seems to imply it may go along with block V.
The bits of F9 that the fairing attaches to are more-or-less static and unchanged over all blocks, as I understand it.
It may well be more expensive, it's certainly newer. Lighter - well - possibly not - recovery hardware isn't air.

I don't think we've seen any reasonable speculation it would be bigger, and Elon did not mention this when he has mentioned much smaller differences in the above conference.

If the fairing is double the price, and you recover and refly nearly all of them, that's a real bargain.

And an answer from a source who knows!
https://twitter.com/elonmusk/status/963095860060934144
Quote
20m20 minutes ago
Replying to @DJSnM @doug_ellison @dsfpspacefl1ght

Under consideration. We’ve already stretched the upper stage once. Easiest part of the rocket to change. Fairing 2, flying soon, also has a slightly larger diameter. Could make fairing much longer if need be & will if BFR takes longer than expected.
Title: Re: Fairing reuse
Post by: rsdavis9 on 02/12/2018 04:46 pm
Do you have any more info about fairing version 2?
It will be part of block V?
Is it supposed to be more expensive to require recovery be "very important"?
Lighter?
Bigger?

The available info seems to imply it may go along with block V.
The bits of F9 that the fairing attaches to are more-or-less static and unchanged over all blocks, as I understand it.
It may well be more expensive, it's certainly newer. Lighter - well - possibly not - recovery hardware isn't air.

I don't think we've seen any reasonable speculation it would be bigger, and Elon did not mention this when he has mentioned much smaller differences in the above conference.

If the fairing is double the price, and you recover and refly nearly all of them, that's a real bargain.

And an answer from a source who knows!
https://twitter.com/elonmusk/status/963095860060934144
Quote
20m20 minutes ago
Replying to @DJSnM @doug_ellison @dsfpspacefl1ght

Under consideration. We’ve already stretched the upper stage once. Easiest part of the rocket to change. Fairing 2, flying soon, also has a slightly larger diameter. Could make fairing much longer if need be & will if BFR takes longer than expected.

with wider fairing he wont have to tilt the next car.  :)
Title: Re: Fairing reuse
Post by: cscott on 02/12/2018 06:32 pm
Do you have any more info about fairing version 2?
It will be part of block V?
Is it supposed to be more expensive to require recovery be "very important"?
Lighter?
Bigger?

The available info seems to imply it may go along with block V.
The bits of F9 that the fairing attaches to are more-or-less static and unchanged over all blocks, as I understand it.
It may well be more expensive, it's certainly newer. Lighter - well - possibly not - recovery hardware isn't air.

I don't think we've seen any reasonable speculation it would be bigger, and Elon did not mention this when he has mentioned much smaller differences in the above conference.

If the fairing is double the price, and you recover and refly nearly all of them, that's a real bargain.

And an answer from a source who knows!
https://twitter.com/elonmusk/status/963095860060934144
Quote
20m20 minutes ago
Replying to @DJSnM @doug_ellison @dsfpspacefl1ght

Under consideration. We’ve already stretched the upper stage once. Easiest part of the rocket to change. Fairing 2, flying soon, also has a slightly larger diameter. Could make fairing much longer if need be & will if BFR takes longer than expected.

with wider fairing he wont have to tilt the next car.  :)
I think we established that the car wouldn't have had to be tilted to fit in the current fairing.

Offtopic: I think the tilt was done for aesthetic reasons.  If you think about the hero images produced (fairing deploy, slowly rotating starman, etc) it seems clear that they carefully choreographed the exact camera angles, roll rates, etc, to get the earth framed properly in the shot. I'm pretty sure equal attention was paid to framing the car on top of the stage.
Title: Re: Fairing reuse
Post by: rpapo on 02/12/2018 11:19 pm
Offtopic: I think the tilt was done for aesthetic reasons.  If you think about the hero images produced (fairing deploy, slowly rotating starman, etc) it seems clear that they carefully choreographed the exact camera angles, roll rates, etc, to get the earth framed properly in the shot. I'm pretty sure equal attention was paid to framing the car on top of the stage.
And further off-topic: With the car tilted like that, the second stage didn't appear in the camera views.  At all.  The only hint the stage was back there was when the cold gas thrusters fired.
Title: Re: Fairing reuse
Post by: deruch on 02/14/2018 10:56 am
Really hoping they add at least 4" to the diameter of the payload envelope.  My pet "crazy idea" mission has a payload diameter of 4.7m and the SpaceX fairing limits payloads to 4.6m.
Title: Re: Fairing reuse
Post by: Espen on 02/16/2018 11:46 am
Since there is only boat with a giant net, could it be that fairing 2.0 is able to separate as some sort of clam shell and even close it self back up before coming down through the atmosphere? I vaguely remember Elon mentioning the aerodynamics of the half fairing and parachute was causing problems, a closed up whole fairing could maybe help solve that problem?
Title: Re: Fairing reuse
Post by: speedevil on 02/16/2018 11:58 am
Since there is only boat with a giant net, could it be that fairing 2.0 is able to separate as some sort of clam shell and even close it self back up before coming down through the atmosphere? I vaguely remember Elon mentioning the aerodynamics of the half fairing and parachute was causing problems, a closed up whole fairing could maybe help solve that problem?

It's not a completely insane idea.
However, the forces involved on the seams would be quite large indeed, and the manoevering and latching would be major problems.
If they could get this working, there are any number of other interesting possibilities that arise, as it demonstrates very interesting in-space reassembly.

On a scale of 0-10 in likelyhood of happening, I rate this as -3.
Title: Re: Fairing reuse
Post by: Johnnyhinbos on 02/16/2018 12:31 pm
I can’t come up with a realistic way the two halves could separate as a unit from the second stage without a high probability of damage to the payload. Now, DOCKING the two halves post separation to become one unit...

(Kidding... right?)
Title: Re: Fairing reuse
Post by: rsdavis9 on 02/16/2018 12:39 pm
lots of string. :)
Title: Re: Fairing reuse
Post by: mme on 02/16/2018 02:48 pm
Since there is only boat with a giant net, could it be that fairing 2.0 is able to separate as some sort of clam shell and even close it self back up before coming down through the atmosphere? I vaguely remember Elon mentioning the aerodynamics of the half fairing and parachute was causing problems, a closed up whole fairing could maybe help solve that problem?
They are only trying to catch one half now.  Once they have that sorted out they will either:
1. Add another boat to catch the other fairing.
2. Add a mechanism to allow one boat to catch 2 fairings.

My money is on #1. If they do #2, it'll be later. Incremental development is the SpaceX way.
Title: Re: Fairing reuse
Post by: Alastor on 02/16/2018 03:52 pm
Since there is only boat with a giant net, could it be that fairing 2.0 is able to separate as some sort of clam shell and even close it self back up before coming down through the atmosphere? I vaguely remember Elon mentioning the aerodynamics of the half fairing and parachute was causing problems, a closed up whole fairing could maybe help solve that problem?

If there was a fairing drinking game, this would definitely be part of it.
It seems about everyone remotely interested in what SpaceX is doing with the fairing has or will promote this idea at some point, despite fairing separation being a nightmare with this kind of design and fairing rejoining being even worse, without even talking about reentry loads. And let's not start with Rube Goldberg-esque devices involving strings and rubber bands (and probably chewing gum for structural integrity).

So no. they're definitely not doing that. :-)
Title: Re: Fairing reuse
Post by: freddo411 on 02/16/2018 04:40 pm
Since there is only boat with a giant net, could it be that fairing 2.0 is able to separate as some sort of clam shell and even close it self back up before coming down through the atmosphere? I vaguely remember Elon mentioning the aerodynamics of the half fairing and parachute was causing problems, a closed up whole fairing could maybe help solve that problem?

While it would not fit the current Falcon 9 design and flight profile, a first stage booster with a clam shell fairing containing both the second stage and the payload seems quite possible.    The fairing mass and aerodynamics would seem to be well suited to flying back attached firmly to the first stage booster.

Of course, this implies that the staging event happens high enough up that the fairing is no longer needed.
Title: Re: Fairing reuse
Post by: speedevil on 02/16/2018 04:54 pm
While it would not fit the current Falcon 9 design and flight profile, a first stage booster with a clam shell fairing containing both the second stage and the payload seems quite possible.    The fairing mass and aerodynamic woulds seem to be well suited to flying back attached firmly to the first stage booster.

I think they already announced that.
A first stage capable of lifting a F9 stage 2, to 5km/s or so, and releasing it without needing a fairing.

(BFS-cargo variant, without BFR)

More seriously, it seems pretty certain to me that the fairing is a lightly modified version of the existing one with a little extra recovery hardware added, and production changed so as to make it easier and cheaper for them to make in the future, while allowing the option of longer fairings without prohibitive investment in one-offs.

Boats are way, way cheaper than fairings, there is little reason to try to catch two on one boat.
Boats are way, way, way cheaper than redesigning the whole first stage.
Title: Re: Fairing reuse
Post by: Space Ghost 1962 on 02/16/2018 07:31 pm
As this discussion is a bit out of control, lets get back to the basics about fairings.

On ascent, the fairing's protect the payload (so it doesn't have to do so as a capsule usually does) from aeroloads.

When there are no aeroloads, there is no reason to keep lifting the fairing, so it's jettisoned along the separation plane, so that nothing intersects the volume of the payload itself in the process. This altitude is roughly the same, and is due to air density.

The fairing halves/thirds/cylinders/cones discarded, fall downrange, shedding considerable delta-v  as they are "fluffy", losing almost all horizontal velocity and falling with terminal velocity determined by drag / ballistic coefficient of area/shape.

Reuse strategy differs greatly here. You either have a recovery of jettisoned parts (retains advantage of more payload to orbit) or you have a fully reusable vehicle that doesn't shed anything and has considerable payload loss that it carry's its entire mission, where what suffices for a fairing has to handle extended in space environment, reentry thermal loads, recovery stresses, processing for reflight. The two are in no way comparable.

SX is experimenting with the circus act of terminal recovery for fairings. Possibly more. It's mostly about a hand-off from one flight regime to some kind of restraining system that absorbs residual velocities within a certain capture cross-section provided by terminal GNC.

add:
Fairing recovery has nothing to do with BFS, adds nothing (actually subtracts in NOT getting on with the SC alone).

Fairing recovery is all about extending economic recovery of conventional launch to disadvantage expendable launch economics.

Note that SX isn't against using specialized means to do this, but, like with the barges, they don't want to own the base vehicles (and the economics they drag along), but to exploit service use they temporarily layer upon them, possibly that can be "salvage sold" after service life return to owner. That way they avoid funding an armada/fleet.

The art of this style of business is to have the least change to the fairing concept, and the most compact recovery apparatus as a addition to a common vehicle.

You might be able to use it more than once a go, by delaying arrival times to stagger encounters, given time to unload and prepare fixtures for next encounter.
Title: Re: Fairing reuse
Post by: speedevil on 02/16/2018 08:39 pm
On ascent, the fairing's protect the payload (so it doesn't have to do so as a capsule usually does) from aeroloads.

When there are no aeroloads, there is no reason to keep lifting the fairing, so it's jettisoned along the separation plane, so that nothing intersects the volume of the payload itself in the process.
Nitpick: The fairing actually detaches when the free molecular heating imparted by the airstream is below about solar input - 1100W/m^2, not due to force as such.

(F9 payload guide)
Title: Re: Fairing reuse
Post by: Space Ghost 1962 on 02/16/2018 09:09 pm
On ascent, the fairing's protect the payload (so it doesn't have to do so as a capsule usually does) from aeroloads.

When there are no aeroloads, there is no reason to keep lifting the fairing, so it's jettisoned along the separation plane, so that nothing intersects the volume of the payload itself in the process.
Nitpick: The fairing actually detaches when the free molecular heating imparted by the airstream is below about solar input - 1100W/m^2, not due to force as such.

(F9 payload guide)
Nitpick on the nitpick: depends on incident particle flux / solar wind (raises density) and velocity of vehicle, as well as ionized oxygen as well. Can also have corona discharge in odd cases too.

Basically you want it to protect until there's nothing you need to be protected against.
Title: Re: Fairing reuse
Post by: deruch on 02/17/2018 12:36 am
On ascent, the fairing's protect the payload (so it doesn't have to do so as a capsule usually does) from aeroloads.

When there are no aeroloads, there is no reason to keep lifting the fairing, so it's jettisoned along the separation plane, so that nothing intersects the volume of the payload itself in the process.
Nitpick: The fairing actually detaches when the free molecular heating imparted by the airstream is below about solar input - 1100W/m^2, not due to force as such.
Nitpick on the nitpick: depends on incident particle flux / solar wind (raises density) and velocity of vehicle, as well as ionized oxygen as well. Can also have corona discharge in odd cases too.

Basically you want it to protect until there's nothing you need to be protected against.

Further wrinkle: payload owners can (potentially for an additional fee) specify a different threshold should they so desire and theoretically it could be one that is not strictly based on or related to FMH.


Since there is only boat with a giant net, could it be that fairing 2.0 is able to separate as some sort of clam shell and even close it self back up before coming down through the atmosphere? I vaguely remember Elon mentioning the aerodynamics of the half fairing and parachute was causing problems, a closed up whole fairing could maybe help solve that problem?

While it would not fit the current Falcon 9 design and flight profile, a first stage booster with a clam shell fairing containing both the second stage and the payload seems quite possible.    The fairing mass and aerodynamics would seem to be well suited to flying back attached firmly to the first stage booster.

Of course, this implies that the staging event happens high enough up that the fairing is no longer needed.
In addition to significantly altering the ascent aerodynamics, such a solution would also pretty much totally invalidate all the work they've done on recovering 1st stages so far.  Even the relatively minimal change of adding a nose cone (for the FH side cores) had significant impacts.  You're suggesting putting a huge aerodynamic appendage on the top which would effectively move the grid fins to the middle half of the booster and into a position where they lose a significant amount of their effectiveness.  All this, plus the challenge of designing the new fairings and changing the opening mechanism.  Plus new challenges for staging the vehicle, etc.  All to save a few million bucks on a design that SpaceX doesn't want to put much future effort into. 

If the suggestion was that "someone" (not SpaceX) could look into doing things this way--with a different vehicle at some point in the future--I might say okay.  But, IMO, there's 0% chance that SpaceX tries it.
Title: Re: Fairing reuse
Post by: freddo411 on 02/17/2018 02:22 am
On ascent, the fairing's protect the payload (so it doesn't have to do so as a capsule usually does) from aeroloads.

When there are no aeroloads, there is no reason to keep lifting the fairing, so it's jettisoned along the separation plane, so that nothing intersects the volume of the payload itself in the process.
Nitpick: The fairing actually detaches when the free molecular heating imparted by the airstream is below about solar input - 1100W/m^2, not due to force as such.
Nitpick on the nitpick: depends on incident particle flux / solar wind (raises density) and velocity of vehicle, as well as ionized oxygen as well. Can also have corona discharge in odd cases too.

Basically you want it to protect until there's nothing you need to be protected against.

Further wrinkle: payload owners can (potentially for an additional fee) specify a different threshold should they so desire and theoretically it could be one that is not strictly based on or related to FMH.


Since there is only boat with a giant net, could it be that fairing 2.0 is able to separate as some sort of clam shell and even close it self back up before coming down through the atmosphere? I vaguely remember Elon mentioning the aerodynamics of the half fairing and parachute was causing problems, a closed up whole fairing could maybe help solve that problem?

While it would not fit the current Falcon 9 design and flight profile, a first stage booster with a clam shell fairing containing both the second stage and the payload seems quite possible.    The fairing mass and aerodynamics would seem to be well suited to flying back attached firmly to the first stage booster.

Of course, this implies that the staging event happens high enough up that the fairing is no longer needed.
... snip ...

If the suggestion was that "someone" (not SpaceX) could look into doing things this way--with a different vehicle at some point in the future--I might say okay.  But, IMO, there's 0% chance that SpaceX tries it.

Agreed, Falcon 9 isn't going to get something that radical.

The overall idea seems possible as part of a recovered first stage
Title: Re: Fairing reuse
Post by: meberbs on 02/17/2018 06:56 pm
Official:
https://twitter.com/SpaceX/status/964937069901447168
Quote
Team at Vandenberg is taking additional time to perform final checkouts of upgraded fairing. Payload and vehicle remain healthy. Due to mission requirements, now targeting February 21 launch of PAZ.

Sounds like they are now using fairing 2.0. With Mr. Steven on the west coast, maybe we will see full recovery of at least one half this time.
Title: Re: Fairing reuse
Post by: Raul on 02/17/2018 10:50 pm
According to today's photos (https://imgur.com/a/jDorh) is high speed fairing boat Mr.Steven ready with net attached for recovery attempt of upgraded fairing.
Title: Re: Fairing reuse
Post by: speedevil on 02/17/2018 11:22 pm
Awesome!
Seems remarkably 'mundane' from some of the upthread discussions.
No second level, no slide off fairing, no ...
:)
Title: Re: Fairing reuse
Post by: testguy on 02/17/2018 11:26 pm
Awesome!
Seems remarkably 'mundane' from some of the upthread discussions.
No second level, no slide off fairing, no ...
:)

KISS!
Title: Re: Fairing reuse
Post by: OxCartMark on 02/18/2018 03:46 pm
Whynot wouldn't they make a few fiberglass dummy fairing halves and drop them by helicopter onto Mr. Steven?  Seems to me that if you had a pallet load of money falling from the sky you'd want a well practiced catcher.  You can pay thousands per day to sit in port or you can pay a bit more to work out the details of catching fairings.  Unless they've not been able to get the fairings down to a predictable location and under parachute under control.

Regarding the various upthread comments to rejoin the fairing halves with bungee straps etc.  Have we discussed having them fly to each other using N2 thrusters to re-link?  I know there are only 2? 3? minutes before the atmosphere but from the video we've seen they are relatively non-rotating and within a few hundred meters of each other.  I know this sounds like an hour long docking procedure in the old world but from the new world of autonomous computed hoverslams that sounds quite doable.

Title: Re: Fairing reuse
Post by: laszlo on 02/18/2018 04:05 pm
Since there is only boat with a giant net, could it be that fairing 2.0 is able to separate as some sort of clam shell and even close it self back up before coming down through the atmosphere? I vaguely remember Elon mentioning the aerodynamics of the half fairing and parachute was causing problems, a closed up whole fairing could maybe help solve that problem?
They are only trying to catch one half now.  Once they have that sorted out they will either:
1. Add another boat to catch the other fairing.
2. Add a mechanism to allow one boat to catch 2 fairings.

My money is on #1. If they do #2, it'll be later. Incremental development is the SpaceX way.

A second boat is so much simpler and more reliable than anything else mentioned here that it'd be criminal to do it otherwise. It's completely understood technology, no additional risk to the payloads and has a very well-developed and mature industry to support it. Any money spent on clamshells, re-unification, etc. could be much better spent on real R&D.
Title: Re: Fairing reuse
Post by: speedevil on 02/18/2018 04:09 pm
Regarding the various upthread comments to rejoin the fairing halves with bungee straps etc.  Have we discussed having them fly to each other using N2 thrusters to re-link?  I know there are only 2? 3? minutes before the atmosphere but from the video we've seen they are relatively non-rotating and within a few hundred meters of each other.

The fairing halves have to not only come roughly together, but into alignment within a few millimetres, assuming the structures are not warped thermally by more than a few millimeters (wholly reversible easily if cooled to equal temperatures), and then it needs to re-clamp using re-designed clamps that were not initially meant to clamp it.
It then needs to have those clamps take quite large loads when the two fairing halves impact something, as well as other unusual loads they, or perhaps the fairing will not have been designed for.

Boats are cheap.
Exhaustive design efforts and testing on complex carbon fibre structures and redesign of those structures if you can possibly avoid it are not.
Title: Re: Fairing reuse
Post by: OxCartMark on 02/18/2018 04:22 pm
It doesn't take much of a mechanism to re-fasten the fairing halves.  My car has 6 more or less payload fairings that lock to the fixed part of the body with just a simple slam.
Title: Re: Fairing reuse
Post by: speedevil on 02/18/2018 04:23 pm
It doesn't take much of a mechanism to re-fasten the fairing halves.  My car has 6 more or less payload fairings that lock to the fixed part of the body with just a simple slam.

Now, take off the hinge, and try to slam it shut.
Title: Re: Fairing reuse
Post by: dorkmo on 02/18/2018 05:05 pm
I think if they find that single half recovery often damages the carbon fiber integrity, theyd then try docking the halves.It would be tricky but i bet they could figure it out.
Title: Re: Fairing reuse
Post by: AC in NC on 02/18/2018 06:46 pm
I don't understand the naysayers.  It's totally obvious they are going to rejoin the fairing halves.  Enclosing future payloads.
Title: Re: Fairing reuse
Post by: wannamoonbase on 02/18/2018 07:02 pm
I think if they find that single half recovery often damages the carbon fiber integrity, theyd then try docking the halves.It would be tricky but i bet they could figure it out.

No
Title: Re: Fairing reuse
Post by: Space Ghost 1962 on 02/18/2018 07:16 pm
Regarding the various upthread comments to rejoin the fairing halves with bungee straps etc.  Have we discussed having them fly to each other using N2 thrusters to re-link?  I know there are only 2? 3? minutes before the atmosphere but from the video we've seen they are relatively non-rotating and within a few hundred meters of each other.

The fairing halves have to not only come roughly together, but into alignment within a few millimetres, assuming the structures are not warped thermally by more than a few millimeters (wholly reversible easily if cooled to equal temperatures), and then it needs to re-clamp using re-designed clamps that were not initially meant to clamp it.
It then needs to have those clamps take quite large loads when the two fairing halves impact something, as well as other unusual loads they, or perhaps the fairing will not have been designed for.
Not to mention the other bits that make the fairing a fairing.

Recovering a system level component has different challenges than one for remanufacturing, different reuse rates too. As SX found with boosters. They are going for system level, e.g. on a flight shortly - think they've had enough of warehousing for years.

Quote
Boats are cheap.
Exhaustive design efforts and testing on complex carbon fibre structures and redesign of those structures if you can possibly avoid it are not.
Still, there's a functional attachment to using one tool for N retrievals that they're not above.

In looking at Mr Steven, I can see how it could be rigged for 5-10 minute extraction and re rigging.

It's all a cost vs GNC trade - if you can guarantee a 10-15minute dwell time on precision terminal guidance (perhaps "steering into the wind" at a certain FL), and the cost/complexity/operations can handle an unload, might suit.

And you do want to recover the fairing to remove it from the elements ASAP so as to preserve its near immediate reuse.

(BTW, a common trope used against SX's efforts for reuse is the theory of "damaged goods" needing to be remanufactured, thus the excuse that reuse is too hard, so don't try it because the costs will be too high - e.g. "self-cancelling".)

Suggest if we consider reuse in the context of preserving necessary qualities in use/recovery, fairings are like manufacturing fixtures that no one pays a mind to checking again on reuse, because they aren't "abused" in the first place.

How we reduce launch costs is by carefully factoring out the arbitrary cost by replacing process in whole, not in part.
Title: Re: Fairing reuse
Post by: cscott on 02/18/2018 09:20 pm
I don't understand the naysayers.  It's totally obvious they are going to rejoin the fairing halves.  Enclosing future payloads.
It's totally obvious that BFS will use a clamshell, and that BFS will eventually serve most if not all F9 payloads.  Anything else is certainly not "totally obvious".
Title: Re: Fairing reuse
Post by: speedevil on 02/18/2018 09:29 pm
It's totally obvious that BFS will use a clamshell, and that BFS will eventually serve most if not all F9 payloads.

It's not obvious.
At least initially, basically all of the payloads of F9 can be fit through the 3.8*3.8m or so square hatch.
(I did a quick search and did not find one that seemed not to fit in a 3.7*3.7*8m envelope).

The large hatch raises obvious structural issues if you want one hull design, and for one variant to be pressurised.
Are these soluble - sure.
Can you avoid them entirely for no penalty - yes, at least until people start designing large payloads.
Title: Re: Fairing reuse
Post by: AC in NC on 02/18/2018 09:58 pm
I don't understand the naysayers.  It's totally obvious they are going to rejoin the fairing halves.  Enclosing future payloads.
It's totally obvious that BFS will use a clamshell, and that BFS will eventually serve most if not all F9 payloads.  Anything else is certainly not "totally obvious".

Large, the set of anything else is.  Many things, totally obvious are.  Amongst them, you missing the point is.
Title: Re: Fairing reuse
Post by: dorkmo on 02/19/2018 01:24 am
I think if they find that single half recovery often damages the carbon fiber integrity, theyd then try docking the halves.It would be tricky but i bet they could figure it out.

No

Are you suggesting they would they just give up on recovery if they find they are unable to reuse the fairings?
Title: Re: Fairing reuse
Post by: meberbs on 02/19/2018 06:08 am
I think if they find that single half recovery often damages the carbon fiber integrity, theyd then try docking the halves.It would be tricky but i bet they could figure it out.

No

Are you suggesting they would they just give up on recovery if they find they are unable to reuse the fairings?
That is not even close to what was said.

If the fairings are damaged during recovery, attempting to dock the fairing haves would in no way prevent that damage, and would bring in multiple more mechanisms that they could/would be damaged by. In that situation SpaceX would do something that is actually relevant rather than something that makes the problem worse.
Title: Re: Fairing reuse
Post by: Alastor on 02/19/2018 12:15 pm
I think we have all seen how flexible the fairings are.
The only reason they keep structural integrity during launch is because they are attached to a very robust second stage that provides a good structural support.
The reason they keep structural integrity during reentry is that they are so light and not aerodynamic that they brake very fast. A little bit like a feather if you try to throw it very hard.

To have this kind of rigidity during reentry so that the attached fairings do not disintegrate under the significant structural loads applied during the reentry of an aerodynamic object like a closed fairing would mean adding a very heavy new system. They are just not going to do that.

In addition to that, the fact that your object becomes very aerodynamic means a slow breaking in the atmosphere and a lot of reentry shock heating. Again, you don't want to have to add TPS to the fairings.

I'm probably missing dozens of reasons why rejoining the halves without having a vehicle completely designed for that from the very start is just NOT a good idea. Even if it's technically possible, it would in no way make the reentry easier. Even if just for these two reasons.
Title: Re: Fairing reuse
Post by: wannamoonbase on 02/19/2018 12:53 pm
I think if they find that single half recovery often damages the carbon fiber integrity, theyd then try docking the halves.It would be tricky but i bet they could figure it out.

No

Are you suggesting they would they just give up on recovery if they find they are unable to reuse the fairings?
That is not even close to what was said.

If the fairings are damaged during recovery, attempting to dock the fairing haves would in no way prevent that damage, and would bring in multiple more mechanisms that they could/would be damaged by. In that situation SpaceX would do something that is actually relevant rather than something that makes the problem worse.

Yes, that’s what I meant. 

They’ll try a lot of things before they give up.  Reconnecting two massive structures moving thousands of KM an hour, that ain’t happening, ever. 

Edit: What would the benefit be even if you could?

It sounds like they are learning and evolving, they may get there.  It's going to take a number of try, fail, try again, like first stage recovery.
Title: Re: Fairing reuse
Post by: catdlr on 02/20/2018 04:55 am
SpaceX - Go Pursuit - Fairing Hunter 02-19-2018


USLaunchReport
Published on Feb 19, 2018
SUBSCRIBED 19K

The Atlantic has 4 Ships, the Pacific has 4 with more on the way. Today we spotted the new Go Pursuit. Looks designed to haul fairings.

https://youtu.be/T8EFq6bmAJw?t=001

https://youtu.be/T8EFq6bmAJw
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 02/20/2018 05:20 am
shorealone films (https://www.flickr.com/photos/81789298@N05/) has a large selection of Mr Steve photos. A few attached.
Title: Re: Fairing reuse
Post by: swervin on 02/20/2018 08:33 am
Could an internal airbag (if you will) be inflated at the base of the fairing post separation? Think of it as half a circle, maybe 1/2 a meter or so in thickness once inflated (i.e., half a donut). It would be the same shape as the aft-end of the fairing, filling the void and providing strength/rigidity to the structure once separated in half, with some weight penalty, but still kind of lightweight. The payload attach fitting seems to provide a 'void' in the internal volume of the fairing which is (I assume) under utilized and could accommodate the deflated airbag and required high pressure bottles to inflate.

See very crude graphic if made to illustrate. I'm no artist or CAD'er. haha
Credit: PAF graphic from the F9 Users Guide.

v/r,
Splinter
Title: Re: Fairing reuse
Post by: speedevil on 02/20/2018 10:10 am
Could an internal airbag (if you will) be inflated at the base of the fairing post separation?

The stresses of falling into a compliant net for isolated fairing halves, if upright, may be quite small.
There is a tendancy to 'splay out' - but this is in a direction where the structure is naturally flexible, and it's somewhat constrained in doing this by sinking into the net.

I'd only believe it if we see it.
Title: Re: Fairing reuse
Post by: meekGee on 02/20/2018 01:54 pm
Could an internal airbag (if you will) be inflated at the base of the fairing post separation?

The stresses of falling into a compliant net for isolated fairing halves, if upright, may be quite small.
There is a tendancy to 'splay out' - but this is in a direction where the structure is naturally flexible, and it's somewhat constrained in doing this by sinking into the net.

I'd only believe it if we see it.

When.  not if.   it's a morale thing.

EDIT: I'm talking about seeing "a fish in the net".
Title: Re: Fairing reuse
Post by: speedevil on 02/20/2018 02:08 pm
I'd only believe it if we see it.

When.  not if.   it's a morale thing.
[/quote]

An internal airbag.
I would be very surprised if fairing recovery fails to work eventually, possibly first time.
Title: Re: Fairing reuse
Post by: rory on 02/20/2018 04:41 pm
Quote from: Chris B on Twitter
Say hello to Fairing 2.0

https://twitter.com/NASASpaceflight/status/965999852831363072

Quick and dirty comparison gif (click to play):

edit: add side-by-side.
Title: Re: Fairing reuse
Post by: sevenperforce on 02/20/2018 04:45 pm
By my estimate, that's a 5.28-meter fairing.
Title: Re: Fairing reuse
Post by: matthewkantar on 02/20/2018 05:07 pm
8 cm seems like a tiny delta. Wouldn't they need all new tooling for this seemingly insignificant change?
Title: Re: Fairing reuse
Post by: speedevil on 02/20/2018 05:13 pm
8 cm seems like a tiny delta. Wouldn't they need all new tooling for this seemingly insignificant change?

There might be a little margin on the tooling they're using, and they're squeezing that, as they needed new molds for V2 anyway?
It could also be a new production method that allows changing the length of the fairing, perhaps even with some commonalities with BFS.

I'd hoped for a somewhat larger fairing, but as long as recovery is still on the cards...
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 02/20/2018 06:46 pm
According to MarineTraffic.com Mr Steven left port a few minutes ago
Title: Re: Fairing reuse
Post by: sevenperforce on 02/20/2018 07:02 pm
8 cm seems like a tiny delta. Wouldn't they need all new tooling for this seemingly insignificant change?
If it's now a 5.4m fairing, that would be a 20-cm increase on each fairing half.
Title: Re: Fairing reuse
Post by: wannamoonbase on 02/20/2018 07:59 pm
5.4 is the same size for the EELV largest. 

Perhaps the client that requires that EELVs have 5.4m is the driver.
Title: Re: Fairing reuse
Post by: brickmack on 02/20/2018 08:09 pm
EELV doesn't care about external fairing diameter, only internal. Falcon 9 Fairing 1.0 already had a wider internal diameter than Atlas V, making it the widest in the world (minus whatever volume the recovery hardware takes up)
Title: Re: Fairing reuse
Post by: QuantumG on 02/20/2018 08:17 pm
I still think their efforts to-date are merely to improve the targeting and entry-interface with the water. i.e., flying and diving.

The net isn't for catching, it's for hauling.
Title: Re: Fairing reuse
Post by: matthewkantar on 02/20/2018 08:20 pm
I still think their efforts to-date are merely to improve the targeting and entry-interface with the water. i.e., flying and diving.

The net isn't for catching, it's for hauling.

Seems like a lot of metal to haul a fairing. I think the net is so the fairing does not take a dunking in the brine.
Title: Re: Fairing reuse
Post by: AC in NC on 02/20/2018 08:27 pm
The net isn't for catching, it's for hauling.

The net is for catching.  For hauling is nonsensical.
Title: Re: Fairing reuse
Post by: QuantumG on 02/20/2018 08:30 pm
The net is for catching.  For hauling is nonsensical.

Got anything other than your own declaration? I think the net is so they can pull the whole fairing out of the water, wash it down with fresh water, and cover it.
Title: Re: Fairing reuse
Post by: speedevil on 02/20/2018 08:34 pm

Got anything other than your own declaration? I think the net is so they can pull the whole fairi g out of the water, wash it down with fresh water, and cover it.

Quote
We have fairing version two which is the really  important one that we want to recover, so even if we recovered fairing version one, we wouldn't be re-flying it in the future. Fairing two and recovery that's very important, and my guess is - next six months we figure out recovery.
We've got a special boat to catch the fairing, like a catcher's mitt. It's like a giant catchers mitt in boat form.  It's gonna run around and catch the fairing.
Kinda fun.
I think you might be able to do the same thing with dragon so if NASA wants us to, we could try to catch dragon.
Made for the fairing, but it would work for dragon too.
- musk, post FH presser.
Title: Re: Fairing reuse
Post by: Wolfram66 on 02/20/2018 08:35 pm
The net is for catching.  For hauling is nonsensical.

Got anything other than your own declaration? I think the net is so they can pull the whole fairing out of the water, wash it down with fresh water, and cover it.

To Quote JIM>..... WRONG
Title: Re: Fairing reuse
Post by: AC in NC on 02/20/2018 08:37 pm
The net is for catching.  For hauling is nonsensical.

Got anything other than your own declaration? I think the net is so they can pull the whole fairing out of the water, wash it down with fresh water, and cover it.

A net for fishing a fairing out of the water is even more nonsensical than for hauling. 

What more is necessary?  Do you think those pictures above mean nothing?   That's not a net for hauling something and it's not a net for fishing something out of the water.  There's no circumstance under which what you see is fit for the purpose your are fabricating.

If you were going to haul it, that's not the way you would do it.  If you were going to fish it out, that's not the way you would do it.

 ::)
Title: Re: Fairing reuse
Post by: QuantumG on 02/20/2018 08:45 pm
- musk, post FH presser.

I'm wrong. Thanks! See how easy that is? Ya don't have to puff your chest out and blow hot air.

Title: Re: Fairing reuse
Post by: dorkmo on 02/20/2018 10:26 pm
I think if they find that single half recovery often damages the carbon fiber integrity, theyd then try docking the halves.It would be tricky but i bet they could figure it out.

No

Are you suggesting they would they just give up on recovery if they find they are unable to reuse the fairings?
That is not even close to what was said.

If the fairings are damaged during recovery, attempting to dock the fairing haves would in no way prevent that damage, and would bring in multiple more mechanisms that they could/would be damaged by. In that situation SpaceX would do something that is actually relevant rather than something that makes the problem worse.

I disagree with this statement but i guess we'll all know soon enough
Title: Re: Fairing reuse
Post by: Kabloona on 02/21/2018 01:10 pm
According to MarineTraffic.com Mr Steven left port a few minutes ago

Here's a short bit on Mr. Steven. We wish him happy hunting!

https://www.teslarati.com/spacex-fairing-recovery-boat-using-giant-net/
Title: Re: Fairing reuse
Post by: Johnnyhinbos on 02/21/2018 02:29 pm
According to MarineTraffic.com Mr Steven left port a few minutes ago

Here's a short bit on Mr. Steven. We wish him happy hunting!

https://www.teslarati.com/spacex-fairing-recovery-boat-using-giant-net/
Her - we wish her happy hunting. Ships are shes, regardless of name.

Edit to add: Me too - happy hunting!
Title: Re: Fairing reuse
Post by: wannamoonbase on 02/21/2018 02:35 pm
According to MarineTraffic.com Mr Steven left port a few minutes ago

Here's a short bit on Mr. Steven. We wish him happy hunting!

https://www.teslarati.com/spacex-fairing-recovery-boat-using-giant-net/
Her - we wish her happy hunting. Ships are shes, regardless of name.

Edit to add: Me too - happy hunting!

I have a good feeling about this one.  Their approach is evolving and this seems like a pretty capable ship. 

Go SpaceX navy!
Title: Re: Fairing reuse
Post by: RedSky on 02/21/2018 03:10 pm
If a new fairing is $6 million, then a half fairing is $3 million.  What would be the cost of having the netting boat, crew, port costs, maintenance, overhead, etc.  averaged per mission?   How much cost can be netted (no pun intended) recovering a half fairing?

If netting a fairing becomes reliable, would there then be two net-boats (Mr and Mrs Stevens?) eventually in order to capture both halves?

Also, a half fairing must weigh a lot less than a Vulcan engine pod. Could not a helicopter snag and capture the fairing parachute?  Is it too far at sea for a copter, ultimately needing a ship with 2 helipads?  Seems like a lot of cost, I guess.
Title: Re: Fairing reuse
Post by: Kabloona on 02/21/2018 03:19 pm
According to MarineTraffic.com Mr Steven left port a few minutes ago

Here's a short bit on Mr. Steven. We wish him happy hunting!

https://www.teslarati.com/spacex-fairing-recovery-boat-using-giant-net/
Her - we wish her happy hunting. Ships are shes, regardless of name.

Edit to add: Me too - happy hunting!

I'm a sailor and was going to use the proper nautical pronoun, but figured I'd get dinged by someone for calling "him" a "her."  ;)
Title: Re: Fairing reuse
Post by: Kabloona on 02/21/2018 03:29 pm
If a new fairing is $6 million, then a half fairing is $3 million.  What would be the cost of having the netting boat, crew, port costs, maintenance, overhead, etc.  averaged per mission?   How much cost can be netted (no pun intended) recovering a half fairing?

If netting a fairing becomes reliable, would there then be two net-boats (Mr and Mrs Stevens?) eventually in order to capture both halves?

There's a good discussion of Mr. Steven by someone familiar with the ship on L2, including a cost guesstimate per mission. .

Of course, the mission average cost depends largely on how many missions you do per year. My own guesstimate is that for the cost of one fairing half, you could lease Mr. Steven for a year, with port fees, maintenance, etc, pay the crew for several recovery sorties, and still have spare change left over. If so, it's a good investment.

As for the other fairing half, as soon as Mr. Steven catches a fairing half, I'd expect to see a sister ship showing up shortly.
Title: Re: Fairing reuse
Post by: MaxTeranous on 02/21/2018 04:57 pm
If a new fairing is $6 million, then a half fairing is $3 million.  What would be the cost of having the netting boat, crew, port costs, maintenance, overhead, etc.  averaged per mission?   How much cost can be netted (no pun intended) recovering a half fairing?

If netting a fairing becomes reliable, would there then be two net-boats (Mr and Mrs Stevens?) eventually in order to capture both halves?

Also, a half fairing must weigh a lot less than a Vulcan engine pod. Could not a helicopter snag and capture the fairing parachute?  Is it too far at sea for a copter, ultimately needing a ship with 2 helipads?  Seems like a lot of cost, I guess.

Not necessarily exactly half. If all the clever bits of a fairing are all in one half, it may be more like a 4mil/2mil split (or some such). Catch the more expensive half nets you (heh) more than half the cost back with 1 boat.
Title: Re: Fairing reuse
Post by: envy887 on 02/21/2018 05:05 pm
If a new fairing is $6 million, then a half fairing is $3 million.  What would be the cost of having the netting boat, crew, port costs, maintenance, overhead, etc.  averaged per mission?   How much cost can be netted (no pun intended) recovering a half fairing?

If netting a fairing becomes reliable, would there then be two net-boats (Mr and Mrs Stevens?) eventually in order to capture both halves?

Also, a half fairing must weigh a lot less than a Vulcan engine pod. Could not a helicopter snag and capture the fairing parachute?  Is it too far at sea for a copter, ultimately needing a ship with 2 helipads?  Seems like a lot of cost, I guess.

Not necessarily exactly half. If all the clever bits of a fairing are all in one half, it may be more like a 4mil/2mil split (or some such). Catch the more expensive half nets you (heh) more than half the cost back with 1 boat.

If this would actually work for Dragon 2, it would also work for the Vulcan engine pod. They would be about the same size and weight.
Title: Re: Fairing reuse
Post by: Hobbes-22 on 02/21/2018 06:00 pm

Also, a half fairing must weigh a lot less than a Vulcan engine pod. Could not a helicopter snag and capture the fairing parachute? 

SpaceX looked at that a few years ago (2015?). In the end, the production bottleneck they expected didn't pan out (2 mission losses screwed up their planning) and fairing recovery went on the back burner for a while. The fact they've now switched to a ship indicates a helicopter wasn't the best solution.
Title: Re: Fairing reuse
Post by: wannamoonbase on 02/21/2018 06:07 pm
If a new fairing is $6 million, then a half fairing is $3 million.  What would be the cost of having the netting boat, crew, port costs, maintenance, overhead, etc.  averaged per mission?   How much cost can be netted (no pun intended) recovering a half fairing?

If netting a fairing becomes reliable, would there then be two net-boats (Mr and Mrs Stevens?) eventually in order to capture both halves?

There's a good discussion of Mr. Steven by someone familiar with the ship on L2, including a cost guesstimate per mission. .

Of course, the mission average cost depends largely on how many missions you do per year. My own guesstimate is that for the cost of one fairing half, you could lease Mr. Steven for a year, with port fees, maintenance, etc, pay the crew for several recovery sorties, and still have spare change left over. If so, it's a good investment.

As for the other fairing half, as soon as Mr. Steven catches a fairing half, I'd expect to see a sister ship showing up shortly.

Agreed.  In the mean time they can test everything down to the catching on both halves. 

Learning how to fly it, deploy a chute and guide it to where they want it will take lots of attempts and data collection I imagine. 

I don’t know if they test with both halves but I’ve thought it could speed the process, but take more resources. 
Title: Re: Fairing reuse
Post by: LouScheffer on 02/21/2018 07:19 pm

If netting a fairing becomes reliable, would there then be two net-boats (Mr and Mrs Stevens?) eventually in order to capture both halves?

As for the other fairing half, as soon as Mr. Steven catches a fairing half, I'd expect to see a sister ship showing up shortly.
I'm guessing the other way.  If they can catch one half, then they will look at the landing dispersion.  If that looks OK, then they will try to catch one piece on the left, and one on the right.

Why this guess? First, Elon's perpetual question is "How cheaply can you do that, as limited by the laws of physics?"  Clearly two halves will fit in the net without contact, and the net is potentially stiff enough to keep them from contacting, or they could not think of catching Dragons.   So iit's physically possible, and one ship is surely cheaper than two.  So it's worth a try.

As for side by side, a parafoil has pretty good left-right control through the steering lines.  Overshoot and undershoot seem geometrically harder, since the glide angle is much closer to horizontal than vertical.    So that's why I think left/right, not fore/aft.
Title: Re: Fairing reuse
Post by: AC in NC on 02/21/2018 07:40 pm
I'm guessing the other way.  If they can catch one half, then they will look at the landing dispersion.  If that looks OK, then they will try to catch one piece on the left, and one on the right.

I have a hard time seeing a Left-Right-SameNet approach.  I could see a First Lower Net that can be immediately lowered with a Second Higher Drawstring Net that can be pulled tight at the center to replace the lowered first net.
Title: Re: Fairing reuse
Post by: leetdan on 02/21/2018 08:06 pm
Where does this Rube Goldberg nonsense keep coming from?

They could've tried landing the second FH booster on the same pad, or they could try to land two boosters on the same ASDS.  Instead they built a second landing pad, and are building a second ASDS.  For the same reasons, they will use a second boat for the fairing.
Title: Re: Fairing reuse
Post by: cscott on 02/21/2018 08:06 pm
They haven't done it for boosters yet, and the dispersions are lower.

Pretty sure they'd build two boats rather than build a net twice as wide/long as they need for a single fairing.  The existing net appears to be about as big as you can reasonably hang from Mr. Steven.
Title: Re: Fairing reuse
Post by: Lar on 02/21/2018 08:35 pm
According to MarineTraffic.com Mr Steven left port a few minutes ago

Here's a short bit on Mr. Steven. We wish him happy hunting!

https://www.teslarati.com/spacex-fairing-recovery-boat-using-giant-net/
Her - we wish her happy hunting. Ships are shes, regardless of name.

Edit to add: Me too - happy hunting!
Her. Mr. Steven[1]  is a her. :)

Also that article is by Vaporcobra, who might have posted here once or twice :)[2]

1 -  or Go ____
2 -  today, and every day
Title: Re: Fairing reuse
Post by: AC in NC on 02/21/2018 08:50 pm
Where does this Rube Goldberg nonsense keep coming from?

They could've tried landing the second FH booster on the same pad, or they could try to land two boosters on the same ASDS.  Instead they built a second landing pad, and are building a second ASDS.  For the same reasons, they will use a second boat for the fairing.

If partially directed my way, I should have been clearer that I think they'll go with two boats as well.  The drawstring net is more Rube Goldberg than I'd expect SpaceX to pursue.  But I think shows the boundary case for feasible and fit for purpose.

They haven't done it for boosters yet, and the dispersions are lower.

Pretty sure they'd build two boats rather than build a net twice as wide/long as they need for a single fairing.  The existing net appears to be about as big as you can reasonably hang from Mr. Steven.
Title: Re: Fairing reuse
Post by: dwheeler on 02/21/2018 09:31 pm
Maybe a Poll? Nice and easy: One fairing recovery ship or two. Voting ends when they first attempt to recover both halves. (Of course they may never attempt both... )
Title: Re: Fairing reuse
Post by: Kabloona on 02/21/2018 09:36 pm
Voting ends when they first attempt to recover both halves.

Or when the second ship with giant steel arms and a net shows up, whichever is sooner.  ;)
Title: Re: Fairing reuse
Post by: speedevil on 02/21/2018 09:38 pm
If partially directed my way, I should have been clearer that I think they'll go with two boats as well.  The drawstring net is more Rube Goldberg than I'd expect SpaceX to pursue.  But I think shows the boundary case for feasible and fit for purpose.

Another issue is lead-time.
You can probably employ several people who are really, really good with ropes and nets, and get something that has a >50% chance of catching the second half, on the next available launch. You may not be able to find a new boat, buy or lease, modify, train crew, ...

And >50% is all you need, in order for it to be a net win.

(pun sort of intended)
Title: Re: Fairing reuse
Post by: Lar on 02/21/2018 09:49 pm
No poll...
Title: Re: Fairing reuse
Post by: cscott on 02/21/2018 09:59 pm
Voting ends when they first attempt to recover both halves.

Or when the second ship with giant steel arms and a net shows up, whichever is sooner.  ;)
GO Pursuit recently showed up on the East Coast.

No arms.  Yet.
Title: Re: Fairing reuse
Post by: biosehnsucht on 02/21/2018 10:30 pm
Plus, the fairings are coming in much slower, and don't typically explode on failure, so trying to land two of them on the same "target" is not nearly as dangerous as landing two boosters on the same target ... also, they're flatter / not tall as they rest, so they're not really physically interfering with the second thing that arrives.
Title: Re: Fairing reuse
Post by: matthewkantar on 02/21/2018 10:32 pm
Where does this Rube Goldberg nonsense keep coming from?

They could've tried landing the second FH booster on the same pad, or they could try to land two boosters on the same ASDS.  Instead they built a second landing pad, and are building a second ASDS.  For the same reasons, they will use a second boat for the fairing.

The whole net thing is Rube Goldberg already. Catching a descending fairing is much much harder than rigging a pair of nets onto a single set of booms. Picture a horizontal version of a roller furling jib setup. One fairing hits and is lowered, the other net is pulled across the opening with cables.

Matthew
Title: Re: Fairing reuse
Post by: oiorionsbelt on 02/21/2018 10:44 pm
Where does this Rube Goldberg nonsense keep coming from?

They could've tried landing the second FH booster on the same pad, or they could try to land two boosters on the same ASDS.  Instead they built a second landing pad, and are building a second ASDS.  For the same reasons, they will use a second boat for the fairing.
Disagree. Two nets makes a lot of sense. Very simple to implement and highly cost effective if it works. As long as the two halves are separated a little in time and not too much in distance this concept should work easily.

I could see a First Lower Net that can be immediately lowered with a Second Higher Drawstring Net that can be pulled tight at the center to replace the lowered first net.
Title: Re: Fairing reuse
Post by: docmordrid on 02/21/2018 11:03 pm
They should call them GO Trampoline 1 & 2
Title: Re: Fairing reuse
Post by: virnin on 02/21/2018 11:36 pm
They should call them GO Trampoline 1 & 2

Of Course I Won't Drop You
Title: Re: Fairing reuse
Post by: ChrisC on 02/22/2018 04:06 am
Quote
Where does this Rube Goldberg nonsense keep coming from?

If there was an NSF drinking game, one of my contributions would be:

"Every time ChrisC groans about yet another rehashed discussion and suggests you all just go back 20 pages in the thread and reread the last time we jawboned about this, take a sip." :)
Title: Re: Fairing reuse
Post by: Kabloona on 02/22/2018 02:40 pm
Close, but no cigar....


https://www.instagram.com/p/BfgRX-lgIt6/ (https://www.instagram.com/p/BfgRX-lgIt6/)
Title: Re: Fairing reuse
Post by: eeergo on 02/22/2018 02:49 pm
Has it ever been clarified why the "bouncy castle" approach wasn't pursued and they opted for Mr Stevens? Too little landing accuracy even for fairing 2.0?
Title: Re: Fairing reuse
Post by: photonic on 02/22/2018 02:51 pm
Not sure if this has been discussed before: with the probably more difficult part from fairing separation to parachute deploy now proven to work, wouldn't it be time to hire a big helicopter or transport plane, and drop a (dummy-)fairing+parachute from a few km to practice the catching part until it is perfected?
Title: Re: Fairing reuse
Post by: cscott on 02/22/2018 02:54 pm
It appears that the descent rate is too high for the amount of landing accuracy they are getting (day-of-flight wind speeds may factor in as well).  The solution so far seems to have been increased manuveurability of the "catcher's mitt", which prompted a switch from a giant bouncy castle to a net suspended from a very fast boat (and from her public specs Mr. Steven appears to be extremely manuveurable).

Getting within a few football fields now, but from Elon's comment he seems to think the answer is slowing the descent enough to give Mr Steven more time to get under it---as opposed to making the net larger, deploying a huge (but not manuveurable) bouncy castle, resorting to helicopters, or making technical changes to the parachute to increase accuracy. I'm sure they've looked into all of those other things as well, but that's not the direction they are pursuing right now.
Title: Re: Fairing reuse
Post by: cscott on 02/22/2018 02:58 pm
Not sure if this has been discussed before: with the probably more difficult part from fairing separation to parachute deploy now proven to work, wouldn't it be time to hire a big helicopter or transport plane, and drop a (dummy-)fairing+parachute from a few km to practice the catching part until it is perfected?
OTOH they get this test for free, with extremely high fidelity, every time they launch an F9 from the West Coast.  Next test is in a month, according to Elon. I suggest they probably can't turn around new hardware to test much quicker than that. (And fairing production is on the critical path preventing them from launching faster; there's not any excess production capacity there.)

...but if I wanted to argue your point, I'd note that they seem to have just picked up a fairing from the ocean worth ~$5 million new, which is probably unsuitable for reflight but would make an excellent drop test article.
Title: Re: Fairing reuse
Post by: niwax on 02/22/2018 03:26 pm
It appears that the descent rate is too high for the amount of landing accuracy they are getting (day-of-flight wind speeds may factor in as well).  The solution so far seems to have been increased manuveurability of the "catcher's mitt", which prompted a switch from a giant bouncy castle to a net suspended from a very fast boat (and from her public specs Mr. Steven appears to be extremely manuveurable).

Getting within a few football fields now, but from Elon's comment he seems to think the answer is slowing the descent enough to give Mr Steven more time to get under it---as opposed to making the net larger, deploying a huge (but not manuveurable) bouncy castle, resorting to helicopters, or making technical changes to the parachute to increase accuracy. I'm sure they've looked into all of those other things as well, but that's not the direction they are pursuing right now.

I understood that as having larger chutes might also stabilize the trajectory or allow for steering. The issue with the Fairing 1.0 was the interaction with the fairing ruining chute aerodynamics and throwing it off course.
Title: Re: Fairing reuse
Post by: photonic on 02/22/2018 03:27 pm
Not sure if this has been discussed before: with the probably more difficult part from fairing separation to parachute deploy now proven to work, wouldn't it be time to hire a big helicopter or transport plane, and drop a (dummy-)fairing+parachute from a few km to practice the catching part until it is perfected?
OTOH they get this test for free, with extremely high fidelity, every time they launch an F9 from the West Coast.  Next test is in a month, according to Elon. I suggest they probably can't turn around new hardware to test much quicker than that. (And fairing production is on the critical path preventing them from launching faster; there's not any excess production capacity there.)

...but if I wanted to argue your point, I'd note that they seem to have just picked up a fairing from the ocean worth ~$5 million new, which is probably unsuitable for reflight but would make an excellent drop test article.

Yes, the one they picked out of the ocean today would be an obvious choice. My main point, however was to increase the testing rate from once/month to once/day and to do that with and object that isn't worth $5M. They might have to upgrade the hardware a bit (e.g. slightly bigger chute as Elon suggested), but part of it will be tweaking of software, procedures (have both chute and boat steer upwind?) and crew training.
Title: Re: Fairing reuse
Post by: freddo411 on 02/22/2018 04:02 pm
Honest question.

Let's say i want to do drop tests of a 14m x 5.5 meter half cylinder.     What can I rent to haul it into the sky and drop it?   How high can that plane/helicopter/UFO go?
Title: Re: Fairing reuse
Post by: wannamoonbase on 02/22/2018 04:04 pm
Not sure if this has been discussed before: with the probably more difficult part from fairing separation to parachute deploy now proven to work, wouldn't it be time to hire a big helicopter or transport plane, and drop a (dummy-)fairing+parachute from a few km to practice the catching part until it is perfected?
OTOH they get this test for free, with extremely high fidelity, every time they launch an F9 from the West Coast.  Next test is in a month, according to Elon. I suggest they probably can't turn around new hardware to test much quicker than that. (And fairing production is on the critical path preventing them from launching faster; there's not any excess production capacity there.)

...but if I wanted to argue your point, I'd note that they seem to have just picked up a fairing from the ocean worth ~$5 million new, which is probably unsuitable for reflight but would make an excellent drop test article.


Not the worst idea, they now have a $2.5 million dollar test article to work with. 

Would be an expensive test but lets them work it when they want.

However, if they are flying every 2 weeks or so they will have plenty of opportunities to iterate and improve.  But seems they are close and a few more attempts will get them there.

I'm just an engineer, but being able to recover fairings should go a huge way to increasing flight rate.

Edit: Also, it's mind boggling to think that one could get the performance of a FH with only expending an upper stage.
Title: Re: Fairing reuse
Post by: IanThePineapple on 02/22/2018 04:10 pm
Not sure if this has been discussed before: with the probably more difficult part from fairing separation to parachute deploy now proven to work, wouldn't it be time to hire a big helicopter or transport plane, and drop a (dummy-)fairing+parachute from a few km to practice the catching part until it is perfected?
OTOH they get this test for free, with extremely high fidelity, every time they launch an F9 from the West Coast.  Next test is in a month, according to Elon. I suggest they probably can't turn around new hardware to test much quicker than that. (And fairing production is on the critical path preventing them from launching faster; there's not any excess production capacity there.)

...but if I wanted to argue your point, I'd note that they seem to have just picked up a fairing from the ocean worth ~$5 million new, which is probably unsuitable for reflight but would make an excellent drop test article.


Not the worst idea, they now have a $2.5 million dollar test article to work with. 

Would be an expensive test but lets them work it when they want.

However, if they are flying every 2 weeks or so they will have plenty of opportunities to iterate and improve.  But seems they are close and a few more attempts will get them there.

I'm just an engineer, but being able to recover fairings should go a huge way to increasing flight rate.

Edit: Also, it's mind boggling to think that one could get the performance of a FH with only expending an upper stage.

A big bottleneck with the tests is the fact that they only have one Mr Steven-like boat, and that can only catch fairings from Vandenberg launches, which launch from the least used SpaceX launch facility.
Title: Re: Fairing reuse
Post by: speedevil on 02/22/2018 04:17 pm
A big bottleneck with the tests is the fact that they only have one Mr Steven-like boat, and that can only catch fairings from Vandenberg launches, which launch from the least used SpaceX launch facility.

It can in principle be on the other coast in little more than a week (at its current speed, I did not look up maximum speed)
Title: Re: Fairing reuse
Post by: Lars-J on 02/22/2018 04:17 pm
Has it ever been clarified why the "bouncy castle" approach wasn't pursued and they opted for Mr Stevens? Too little landing accuracy even for fairing 2.0?

I don't see that a "bouncy castle" couldn't really practically be bigger than the net, so I don't see how the accuracy matters in a choice between the two methods. And a catching net seems like an easier solution to implement.
Title: Re: Fairing reuse
Post by: photonic on 02/22/2018 04:30 pm
Honest question.

Let's say i want to do drop tests of a 14m x 5.5 meter half cylinder.     What can I rent to haul it into the sky and drop it?   How high can that plane/helicopter/UFO go?

My first thought was to just push it out of the back of a Hercules transport plane (https://en.wikipedia.org/wiki/Lockheed_C-130_Hercules), but that doesn't fit either in length or width :).  There might be bigger planes, but not sure if they do military style air-drops. The alternative would be to use a helicopter similar to a S-64 Skycrane (https://en.wikipedia.org/wiki/Sikorsky_S-64_Skycrane), not sure how high they go.

SpaceX has used those before for testing Dragon's parachutes: video (https://www.youtube.com/watch?v=zq7LgVX-Jdk).
Title: Re: Fairing reuse
Post by: fthomassy on 02/22/2018 04:44 pm
... snip ...
I'm just an engineer, but being able to recover fairings should go a huge way to increasing flight rate.
... snip ...
At the risk of taking you our of context ...
Huge effect on flight rate only if fairings are more critical path than S2. But certainly good potential for saving cost and reducing schedule risk.
Title: Re: Fairing reuse
Post by: cscott on 02/22/2018 05:08 pm
Has it ever been clarified why the "bouncy castle" approach wasn't pursued and they opted for Mr Stevens? Too little landing accuracy even for fairing 2.0?

I don't see that a "bouncy castle" couldn't really practically be bigger than the net, so I don't see how the accuracy matters in a choice between the two methods. And a catching net seems like an easier solution to implement.
I could see that a bouncy castle might be two or three times the size of the net... but they seem to need hundreds of meters, *plus* whatever manuveurability they got out of Mr. Stevens.  So yeah, I agree, seems to be too large for a bouncy castle to be feasible.
Title: Re: Fairing reuse
Post by: cscott on 02/22/2018 05:10 pm
A big bottleneck with the tests is the fact that they only have one Mr Steven-like boat, and that can only catch fairings from Vandenberg launches, which launch from the least used SpaceX launch facility.

It can in principle be on the other coast in little more than a week (at its current speed, I did not look up maximum speed)
Max speed 32kts.
http://www.seatranmarine.com/vessels-1/mr-steven

There could be a several day wait at the Panama Canal, though, if you don't pay $$$ for priority.
Title: Re: Fairing reuse
Post by: cscott on 02/22/2018 05:12 pm
Honest question.

Let's say i want to do drop tests of a 14m x 5.5 meter half cylinder.     What can I rent to haul it into the sky and drop it?   How high can that plane/helicopter/UFO go?
Take a look at the Dragon and Dream Chaser drop tests, well documented in threads here on NSF.  The Dream Chaser thread had a bunch of speculation about which helicopters it might use, which might help get an idea of the available lease market.
Title: Re: Fairing reuse
Post by: M.E.T. on 02/22/2018 05:17 pm
Well, they seem quite capable of bringing the fairing down safely to the water's surface.

Pity they can't just build a fairing that is waterproof, then they have no need of catching it in a net or any other fancy shenanigans. Just drop it gently into the water and pick it up with a crane or helicopter.

Title: Re: Fairing reuse
Post by: robert_d on 02/22/2018 05:27 pm
After seeing how well the fairing looked I wonder if maybe they could kind of revive the "bouncy house" idea. Have a floating structure like a floating dry dock. Motor it over, center it on the fairing, and then inflate further to raise the fairing out of the water on floats. Could provide a freshwater spray to rinse it once it is lifted. Then tow the whole structure back, with the bouncy house protecting the fairing on the way back. Two bouncy houses might be able to be deployed and towed in tandem by one vessel.
Title: Re: Fairing reuse
Post by: cscott on 02/22/2018 05:32 pm
Here are a few still shots from Oxnard this morning.  Some nice plumes at staging and later on some steering jets on the fairings.  At 15 minutes before local sunrise, the sky was already bright enough to wash out an attempted time exposure.

That last photo seems to show both fairing halves manuveuring!

Helodriver agrees:

Puffing jets could be seen from BOTH fairing halves, but more from one than the other.

Title: Re: Fairing reuse
Post by: Lar on 02/22/2018 05:37 pm
Not sure if this has been discussed before: with the probably more difficult part from fairing separation to parachute deploy now proven to work, wouldn't it be time to hire a big helicopter or transport plane, and drop a (dummy-)fairing+parachute from a few km to practice the catching part until it is perfected?
OTOH they get this test for free, with extremely high fidelity, every time they launch an F9 from the West Coast.  Next test is in a month, according to Elon. I suggest they probably can't turn around new hardware to test much quicker than that. (And fairing production is on the critical path preventing them from launching faster; there's not any excess production capacity there.)

...but if I wanted to argue your point, I'd note that they seem to have just picked up a fairing from the ocean worth ~$5 million new, which is probably unsuitable for reflight but would make an excellent drop test article.

We heard 6M the pair, this being the "active half" it might be more than half the value. But 5M/1M ? Maybe. I bet more like 4M/2M ... doesn't reduce the point Cscott makes though.

Also to those saying it's too valuable to use in a drop test, it's not worth anything near the original value now, it got wet. Unless there is a lot of stuff to study, it seems a good use to me (so would be rejected ones that didn't quite autoclave right)

Also to those saying "just make it waterproof" ... Dragon experience suggests "just" isn't exactly easy.

Me, I think Mr. Steven (who apparently did not get renamed or Elon is a few memos behind) is on the wrong coast, but that's just me.
Title: Re: Fairing reuse
Post by: cscott on 02/22/2018 05:45 pm


Me, I think Mr. Steven (who apparently did not get renamed or Elon is a few memos behind) is on the wrong coast, but that's just me.

Interestingly enough, Mr. Steven came from the East Coast.  Used to be a New Orleans ship.

But then GO Pursuit just arrived on the East Coast, perhaps for fairing recovery, so that may be how that issue will be resolved.

I've requested the official abstract of title for Mr. Steven from the coast guard. When it arrives we should have a definitive answer about its ownership and naming.  Of course, it's possible Guice Offshore has renamed it but hasn't gotten around to filing the paperwork yet.  I can't seem to find any name painted on Mr. Steven (other than the large GO) in any of the recent images.  Perhaps the name is new enough it hasn't been painted on yet either.
Title: Re: Fairing reuse
Post by: intrepidpursuit on 02/22/2018 05:55 pm
I hate to be that guy who hasn't read the whole thread, but here I go...

That floating fairing half looks an awful lot like a boat. Carbon fiber isn't super sensitive to salt or moisture that I'm aware of. If they could reseal the vent holes and perhaps make a little inflatable raft section to prevent incursion around the bottom during splashdown, they could just wait for them to fall and pluck them out of the water.

When we talked about this before the idea that they could land upright and float was theory, but now we see that it really works that way. They obviously aren't super sea worthy, but the aeroshell seems fairly easy to seal to keep from damaging it unlike the many ingress points on a stage or a capsule.

Am I missing something here? I must be since they built a giant floating catchers mitt.

EDIT: Partial ninja by M.E.T. I think a ship and a crane is still a much better retrieval method than a helicopter though. Much cheaper and easier.
Title: Re: Fairing reuse
Post by: ClayJar on 02/22/2018 06:02 pm
I've requested the official abstract of title for Mr. Steven from the coast guard. When it arrives we should have a definitive answer about its ownership and naming.  Of course, it's possible Guice Offshore has renamed it but hasn't gotten around to filing the paperwork yet.  I can't seem to find any name painted on Mr. Steven (other than the large GO) in any of the recent images.  Perhaps the name is new enough it hasn't been painted on yet either.

Of course, the real name and what it's called don't have to have much to do with each other, eh?  MARMAC 300/303/304 vs. JRtI/OCISLY, for example.  My sister once called one of our nieces by her real-on-paper name, and the niece had no idea who my sister was talking to.

I imagine we'll find out what Mr. Steven is now known as around the time Elon posts video from a successful catch (or visually exciting not-quite-successful catch).
Title: Re: Fairing reuse
Post by: AC in NC on 02/22/2018 06:04 pm
I can't seem to find any name painted on Mr. Steven (other than the large GO) in any of the recent images.  Perhaps the name is new enough it hasn't been painted on yet either.

Knew I had seen it. 

https://www.teslarati.com/spacex-fairing-recovery-boat-using-giant-net/
ByEric RalphPosted on February 19, 2018

Title: Re: Fairing reuse
Post by: Hobbes-22 on 02/22/2018 06:11 pm

Of course, the real name and what it's called don't have to have much to do with each other, eh?  MARMAC 300/303/304 vs. JRtI/OCISLY, for example. 

one is an individual ship's name, the other a manufacturer name and type. If a ship is built in series, it'll have both.
Title: Re: Fairing reuse
Post by: Steve D on 02/22/2018 06:14 pm
I keep seeing people saying if it lands on the boat it doesnt have to be waterproof. These people obviously have never been on an oil rig crew boat. Even if it lands on the boat chances are it will be soaked from salt water spray long before it reaches shore. These fairings will have to be "Marine Grade" or they will need a great deal of work done to them.
Title: Re: Fairing reuse
Post by: Lar on 02/22/2018 06:20 pm
That pic shows the old name (maybe the only name, if it's not changed). Too early to tell if they are going to rename. Cool pic though.
Title: Re: Fairing reuse
Post by: AC in NC on 02/22/2018 06:32 pm
That pic shows the old name (maybe the only name, if it's not changed). Too early to tell if they are going to rename. Cool pic though.

Gack!!!  I missed the naming direction???   :o

I need an App to keep up with the current state-of-the-art on all threads and subthreads.   :-[
Title: Re: Fairing reuse
Post by: M.E.T. on 02/22/2018 07:21 pm
So the cumulative return earned from achieving succesful fairing reuse will depend heavily on the total number of Falcon 9/Heavy flights over the lifetime of the rocket. If we go with the $6m fairing cost estimate, and subtract $1m for recovery R&D, recovery operations and refurbishment, that gives you $5m saved per fairing.

So what is the latest estimate for total lifetime Falcon flights? 500? 1000? That gives you at best $5bn savings over say a period of 10 years. (Assuming 10 years of Falcon operations before BFR takes over).

Most likey it will be closer to half that, if only one fairing is recovered, or if there are fewer than 1000 lifetime Falcon flights. So maybe $2.5bn savings then. But, because the $2.5bn is spread over ten years, it is not $2.5bn in present value dollars. Without doing a calculation based on some kind of discount rate, I would guess that it is then probably closer to $1.5bn in current dollars.

Now granted, the above is a back of a napkin kind of calculation, and doesn't take into account a whole host of other factors, like fairings costing more over time etc, but the question I'm raising (without necessarily knowing what the answer is), is whether such a relatively small saving is worth all the effort? Especially in  light of potential $30bn annual Starlink revenues, and the fact that this is not a long term issue. Once BFR arrives, fairing recovery capabilities become irrelevant.

So what say you guys?
Title: Re: Fairing reuse
Post by: AC in NC on 02/22/2018 07:26 pm
but the question I'm raising (without necessarily knowing what the answer is), is whether such a relatively small saving is worth all the effort? Especially in  light of potential $30bn annual Starlink revenues, and the fact that this is not a long term issue. Once BFR arrives, fairing recovery capabilities become irrelevant.

So what say you guys?

Every ~$5M in incremental cost avoidance has an outsized impact on BFR arrival.
Title: Re: Fairing reuse
Post by: wannamoonbase on 02/22/2018 07:59 pm
but the question I'm raising (without necessarily knowing what the answer is), is whether such a relatively small saving is worth all the effort? Especially in  light of potential $30bn annual Starlink revenues, and the fact that this is not a long term issue. Once BFR arrives, fairing recovery capabilities become irrelevant.

So what say you guys?

Every ~$5M in incremental cost avoidance has an outsized impact on BFR arrival.

Agreed, the $5 million is significant in increasing revenue per launch.  Also, it's a culture to make as much reuseable as possible. 

SpaceX needs every million dollars they can get their hands on to develop and deploy both.

The Starlink revenues and BFR are a long way off at this time.  We all know that EM reaches his goals, just no where near his stated schedules.
Title: Re: Fairing reuse
Post by: Lar on 02/22/2018 08:07 pm
"It's only 5M saved" is OldSpace thinking.

If the cost savings per launch (after amortizing the R&D program, costs of boats, refurb, changes to fairing HW, payload impact, everything) were 50K I bet Elon STILL would do it.  But I think they will be a lot more per launch than that.

One fairing recovered and reused probably pays the charter cost for Mr. Steven for 2 years.

AND don't forget to put "not having to build a second fairing production line" on the other side of your cost calculation spreadsheet.

(we've discussed all this upthread, so this is a summarization)
Title: Re: Fairing reuse
Post by: ZachF on 02/22/2018 08:11 pm
but the question I'm raising (without necessarily knowing what the answer is), is whether such a relatively small saving is worth all the effort? Especially in  light of potential $30bn annual Starlink revenues, and the fact that this is not a long term issue. Once BFR arrives, fairing recovery capabilities become irrelevant.

So what say you guys?

Every ~$5M in incremental cost avoidance has an outsized impact on BFR arrival.

Agreed, the $5 million is significant in increasing revenue per launch.  Also, it's a culture to make as much reuseable as possible. 

SpaceX needs every million dollars they can get their hands on to develop and deploy both.

The Starlink revenues and BFR are a long way off at this time.  We all know that EM reaches his goals, just no where near his stated schedules.

SpaceX wants to get eventually up to ~50 launches per year, that $5m adds up to a quarter of a billion per year... not small change to anyone.
Title: Re: Fairing reuse
Post by: speedevil on 02/22/2018 08:22 pm
SpaceX wants to get eventually up to ~50 launches per year, that $5m adds up to a quarter of a billion per year... not small change to anyone.

If you believe starlink will happen on schedule and BFS-SSTO will not happen in the next several years, 'eventually' is coming really, really soon, and 50 probably won't cut it, further strengthening the above point.
Title: Re: Fairing reuse
Post by: abaddon on 02/22/2018 08:40 pm
I keep seeing people saying if it lands on the boat it doesnt have to be waterproof. These people obviously have never been on an oil rig crew boat. Even if it lands on the boat chances are it will be soaked from salt water spray long before it reaches shore. These fairings will have to be "Marine Grade" or they will need a great deal of work done to them.
Can't they lower it onto the deck and cover it with a plastic tarp?  Compared to everything else this seems dead easy to solve.
Title: Re: Fairing reuse
Post by: abaddon on 02/22/2018 08:47 pm
So the cumulative return earned from achieving succesful fairing reuse will depend heavily on the total number of Falcon 9/Heavy flights over the lifetime of the rocket. If we go with the $6m fairing cost estimate, and subtract $1m for recovery R&D, recovery operations and refurbishment, that gives you $5m saved per fairing.
First off, if SpaceX spends a million per recovery, I'll eat my hat.  I don't have one really but I will buy it and eat it.  It's going to be closer to zero cost than a million per recovery op.
[EDIT] I see you had "refurbishment" in there too.  I can't really see that either, but it is at least a reasonable pessimistic assumption.
Quote
I would guess that it is then probably closer to $1.5bn in current dollars. [...] is worth all the effort?
Even with the flawed assumptions... based on Elon's cost estimates, that would pay for F9 reusable and FH development costs.  In other words, SpaceX can do a lot with 1.5 billion.

Further, Starlink may never materialize as a viable concept, and while I do think BFR will happen it will likely take a lot longer than the (admittedly best case) aspirational estimates.

So - yeah.  Definitely worth it.

[EDIT2] Forgot to add, you also need to consider the cost to expand the fairing production line to be able to produce the number of fairings required without reuse and factor that into the comparison with the recovery op and refurbishment costs.
Title: Re: Fairing reuse
Post by: cscott on 02/22/2018 08:50 pm
That pic shows the old name (maybe the only name, if it's not changed). Too early to tell if they are going to rename. Cool pic though.

Gack!!!  I missed the naming direction???   :o

I need an App to keep up with the current state-of-the-art on all threads and subthreads.   :-[
Interestingly, it still shows GO Quest has "NRC Quest" painted on her stern.  So maybe these Guice Offshore folks (Billy and Nathan Guice) aren't very good about updating the paint, beyond breaking out the big GO stencil.

But those pics are a good indicator of where to look for the new name.  Hopefully someone will get a good shot from the stern side when Go Something returns her haul of fairing.
Title: Re: Fairing reuse
Post by: Lar on 02/22/2018 08:54 pm
I keep seeing people saying if it lands on the boat it doesnt have to be waterproof. These people obviously have never been on an oil rig crew boat. Even if it lands on the boat chances are it will be soaked from salt water spray long before it reaches shore. These fairings will have to be "Marine Grade" or they will need a great deal of work done to them.
Can't they lower it onto the deck and cover it with a plastic tarp?  Compared to everything else this seems dead easy to solve.
I think you really need basically a watertight container, spray gets into everything, including around tarps.

...when Go Something returns her haul of fairing.
I think that assumes that she has a crane or rigging capable of bringing the fairing aboard. Or that another (new) sibling is dispatched to assist. I think it likely but not certain.
Title: Re: Fairing reuse
Post by: cscott on 02/22/2018 08:57 pm
Re: fairing recovery being "worth it" --- don't forget that this is a fruitful R&D activity for a company very interested in atmospheric reentry of various types.  I've no doubt that they are gathering a huge amount of data/validating models/etc which could make the *development* of fairing recovery worthwhile even if it is never product-ized, so to speak.
Title: Re: Fairing reuse
Post by: M.E.T. on 02/22/2018 09:00 pm
So the cumulative return earned from achieving succesful fairing reuse will depend heavily on the total number of Falcon 9/Heavy flights over the lifetime of the rocket. If we go with the $6m fairing cost estimate, and subtract $1m for recovery R&D, recovery operations and refurbishment, that gives you $5m saved per fairing.
First off, if SpaceX spends a million per recovery, I'll eat my hat.  I don't have one really but I will buy it and eat it.  It's going to be closer to zero cost than a million per recovery op.
[EDIT] I see you had "refurbishment" in there too.  I can't really see that either, but it is at least a reasonable pessimistic assumption.
Quote
I would guess that it is then probably closer to $1.5bn in current dollars. [...] is worth all the effort?
Even with the flawed assumptions... based on Elon's cost estimates, that would pay for F9 reusable and FH development costs.  In other words, SpaceX can do a lot with 1.5 billion.

Further, Starlink may never materialize as a viable concept, and while I do think BFR will happen it will likely take a lot longer than the (admittedly best case) aspirational estimates.

So - yeah.  Definitely worth it.

[EDIT2] Forgot to add, you also need to consider the cost to expand the fairing production line to be able to produce the number of fairings required without reuse and factor that into the comparison with the recovery op and refurbishment costs.

Good points. As I said, I'm merely asking the question.

I will say that there are some optimistic assumptions in my estimate too. Such as the supposed 1000 flights. Even at 50 a year it would take 10 years for Falcon to reach 500 flights, and surely in 10 years BFR will be operational. So 1000 flights seem a bit ambitious at this stage.

Secondly, it still seems as if they will only catch one fairing per boat. Meaning you would need 2 boats to recover the full fairing. Even if, as someone has estimated,  the fairing cost is split $4m/$2m between the two halves, you are faced with either a scenario where only the more expensive half is recovered, or you need to incur double the recovery cost.

Add in the R&D and refurbishment costs and I don't see a cost of $1m per recovery as being excessive (meaning $5m of the $6m dollars recovered). (EDIT: Also note that this assumes that the same fairing is recovered and reused 500 times, but we know that won't be the case, with fairings surely having a maximum lifetime, just like Block 5 cores have. We can then conservatively estimate a life of 10 flights per fairing, I guess. So that too will have a slight impact on overall costs.)

So you are indeed looking at around $2.5bn saved over a 10 year period. And discounted to today's money, probably under $2bn.

Now, all of the above was merely to get a ballpark estimate of what is at stake. And the answer seems to be around $2bn. And you are quite correct that $2bn goes a long way in developing BFR.
Title: Re: Fairing reuse
Post by: cscott on 02/22/2018 09:00 pm


...when Go Something returns her haul of fairing.
I think that assumes that she has a crane or rigging capable of bringing the fairing aboard. Or that another (new) sibling is dispatched to assist. I think it likely but not certain.

GO Quest definitely has the required hardware, though it usually uses it to fish for Dragon.  I couldn't identify a crane for certain on Mr. Steven, but I'm fairly certain they would have prepared for this eventuality.
Title: Re: Fairing reuse
Post by: Testraindrop on 02/22/2018 10:49 pm
... $1.5bn in current dollars... relatively small saving is worth all the effort?

Going by Elons numbers with this "relatively small saving" SpaceX could develop (not only manufacture) 3 other Falcon Heavys...
Title: Re: Fairing reuse
Post by: DreamyPickle on 02/22/2018 10:58 pm
Calculating the cost of producing a fairing as "savings" on each flight might be too simplistic.

I remember reading various complaints that the current fairings are very slow to build and are a limiting factor on launch rate. The alternative to investing in reusability would be investing into tooling for an expanded production line, that too would be a big one-time cost.
Title: Re: Fairing reuse
Post by: wannamoonbase on 02/22/2018 11:14 pm
Calculating the cost of producing a fairing as "savings" on each flight might be too simplistic.

I remember reading various complaints that the current fairings are very slow to build and are a limiting factor on launch rate. The alternative to investing in reusability would be investing into tooling for an expanded production line, that too would be a big one-time cost.

It’d also be an expensive on going cost.

Who knows what reusing a fairing will cost or how many times they can be reused.  If caught without damage it would see it could be pretty high with raid turn around. 

That could go a long way with helping a Starlink required flight rate.
Title: Re: Fairing reuse
Post by: Lar on 02/22/2018 11:15 pm
Calculating the cost of producing a fairing as "savings" on each flight might be too simplistic.

I remember reading various complaints that the current fairings are very slow to build and are a limiting factor on launch rate. The alternative to investing in reusability would be investing into tooling for an expanded production line, that too would be a big one-time cost.

"It's only 5M saved" is OldSpace thinking.

If the cost savings per launch (after amortizing the R&D program, costs of boats, refurb, changes to fairing HW, payload impact, everything) were 50K I bet Elon STILL would do it.  But I think they will be a lot more per launch than that.

One fairing recovered and reused probably pays the charter cost for Mr. Steven for 2 years.

AND don't forget to put "not having to build a second fairing production line" on the other side of your cost calculation spreadsheet.

(we've discussed all this upthread, so this is a summarization)

I think we're all in agreement here? Any more?
Title: Re: Fairing reuse
Post by: freddo411 on 02/23/2018 12:41 am
From the picture of the floating fairing half. Does it seem like that SX have 2 identical fairing 2.0 halves? In particularly the vertical separation line of the fairing halves.

I don't know, but it would be very clever of SpaceX to build them that way.
Title: Re: Fairing reuse
Post by: wannamoonbase on 02/23/2018 02:17 am
From the picture of the floating fairing half. Does it seem like that SX have 2 identical fairing 2.0 halves? In particularly the vertical separation line of the fairing halves.

I don't know, but it would be very clever of SpaceX to build them that way.

Great point, then any one half could pair with any other half.

First stage reuse is massive, but fairing reuse could also contribute significantly.

Plus the videos of the return and capture should be pretty epic.

I still think that being able to deliver F9 and FH capability with only expending an upper stage is such a massive step forward for space flight.  Just huge.
Title: Re: Fairing reuse
Post by: CeeJayDugan on 02/23/2018 02:48 am
I searched around this thread but didn't see an answer...so for the non engineer, how does the fairing survive reentry stress, temps? It separates higher than the first stage which requires reentry burn to survive. Is the fairing coated with an ablative coating? Or because it's so light in comparison it does not have the velocity to cause it to heat up as much? It just looked so pristine on it's exterior bobbing in the ocean. I expected it to look a little worse for wear.
Title: Re: Fairing reuse
Post by: speedevil on 02/23/2018 03:14 am
I searched around this thread but didn't see an answer...so for the non engineer, how does the fairing survive reentry stress, temps?

The fairing weighs about 2 tons, per half, and has an area of around 50m^2.
The rocket first stage weighs about 30 tons (with fuel for landing and legs) and has an area of about 10m^2 (depending on how you measure).

This means that per square meter, the fairing weighs about 40kg/m^2, and the rocket 3000kg/m^2.

Reentry heat is (sort of roughly) directly related to the areal weight of the object.
Sheets of paper have made it down from the shuttle reentry accident.
Title: Re: Fairing reuse
Post by: kaiser on 02/23/2018 04:08 am
I keep seeing people saying if it lands on the boat it doesnt have to be waterproof. These people obviously have never been on an oil rig crew boat. Even if it lands on the boat chances are it will be soaked from salt water spray long before it reaches shore. These fairings will have to be "Marine Grade" or they will need a great deal of work done to them.
Can't they lower it onto the deck and cover it with a plastic tarp?  Compared to everything else this seems dead easy to solve.
I think you really need basically a watertight container, spray gets into everything, including around tarps.

I've been out to sea quite a few times on boats the same length as Mr. Steven with much lower drafts, and I've kept super sensitive stuff bone dry with simple tarp rigging just keeping things a couple of feet off the deck.

If you have some crazy waves and wind you can get a lot of salt spray, but it's not super bad if you know how to secure a tarp well.

But yea, for $5M I would probably drop it into a very large box and close the top well.  Makes it easier to get off the boat port-side too.

As an aside -- I go to sea with aluminum honeycomb wrapped in carbon fiber with a layer of paint on it.  It's pretty marine grade -- we don't protect it at all other than a fresh water rinse once a week or so.  Stands up for months and months of time of exposure before we get any issues, and once you get through the paint there's still many layers of composite that's pretty darn resistant.  Edges are all sealed as best practice, so shouldn't really be an issue with water getting into the honeycomb.
Title: Re: Fairing reuse
Post by: cscott on 02/23/2018 02:35 pm
If the two fairing halves are identical, is there still an "active" half and a "passive" half wrt latches?  If the latches are also symmetric, then recovering both fairing halves could be as easy as mating two "active" halves ("active" now just meaning "with recovery hardware") together.

Wrt "pristine" looking fairings: most of the blackening on returned stages is soot blown backwards from the landing and reentry burns (and mostly from engine startup it appears).  There's a great clip of video from one of the most recent RTLS landings where you can see the stage blackening as the burn starts.  The FH boosters also got toasted on top from flying through the center stage exhaust.

Given that the fairings do not have Merlins to ignite, they should look pristine so long as they manage to avoid the S2 exhaust plume---and good separation distance from S2 is pretty much their only job.  (In footage you can see them fall well off to the side of the stage.)
Title: Re: Fairing reuse
Post by: eeergo on 02/23/2018 04:08 pm


...when Go Something returns her haul of fairing.
I think that assumes that she has a crane or rigging capable of bringing the fairing aboard. Or that another (new) sibling is dispatched to assist. I think it likely but not certain.

GO Quest definitely has the required hardware, though it usually uses it to fish for Dragon.  I couldn't identify a crane for certain on Mr. Steven, but I'm fairly certain they would have prepared for this eventuality.

Crane (or the likes) confirmed :)

https://forum.nasaspaceflight.com/index.php?topic=44892.msg1792286#msg1792286
Title: Re: Fairing reuse
Post by: cscott on 02/23/2018 04:52 pm
No tarps on the fairings, though.  Guess they're not afraid of a little salt spray.
Title: Re: Fairing reuse
Post by: SLC on 02/23/2018 05:00 pm
There might be problems with dangling a fairing half from a helicopter, either for catching:


Also, a half fairing must weigh a lot less than a Vulcan engine pod. Could not a helicopter snag and capture the fairing parachute? 

SpaceX looked at that a few years ago (2015?). In the end, the production bottleneck they expected didn't pan out (2 mission losses screwed up their planning) and fairing recovery went on the back burner for a while. The fact they've now switched to a ship indicates a helicopter wasn't the best solution.

... or for test-dropping:

Honest question.

Let's say i want to do drop tests of a 14m x 5.5 meter half cylinder.     What can I rent to haul it into the sky and drop it?   How high can that plane/helicopter/UFO go?
Take a look at the Dragon and Dream Chaser drop tests, well documented in threads here on NSF.  The Dream Chaser thread had a bunch of speculation about which helicopters it might use, which might help get an idea of the available lease market.

I seem to remember, from a discussion way upthread, that people who know about helicopters thought a dangling fairing half might be dangerously unmanageable.  With such a low mass and large area, it's going to be blown around unpredictably by the down-draft from the rotor.  Its shape makes this worse, as it changes from an inverted parachute to a sort-of-aerofoil as it rocks from side to side.  There could be all kinds of feedback: the pilot's control responses to the swaying load will redirect the down-draft, and that might amplify the swaying ... you see the problem. 

So it's all very well to dangle, drop or catch a compact heavy object like a Vulcan engine or a Dream Chaser, but maybe not so easy with a fairing, even though it is lighter.
Title: Re: Fairing reuse
Post by: John Alan on 02/23/2018 05:36 pm
Too bad they could not arrange use of a C-17 from time to time... You know, a "training" flight...  ;D
(I checked... C-130 to narrow... C-17 is tight but should clear on width...)
Objective... take these pallets here with their payload to altitude and demonstrate payload extraction at altitude...
Drogue chute dropped overboard pulls a pallet out and the fairing half flies off the rapidly descending pallet...

Just a thought on sub-topic... how to get a clean fairing air drop...  ;)

On edit...
Just don't try it with big heavy things, as the Air Force found out...  :-[
https://www.youtube.com/watch?v=Xd94Rfi_gng (https://www.youtube.com/watch?v=Xd94Rfi_gng)
Weight and specs of thing dropped found here...  :o
https://goo.gl/images/ZfPLXK (https://goo.gl/images/ZfPLXK)
 
Title: Re: Fairing reuse
Post by: cebri on 02/23/2018 06:19 pm
@Teslarati

(https://cdn.teslarati.com/wp-content/uploads/2018/02/Mr-Steven-and-fairing-detail-2-Pauline-Acalin.jpg)
(https://cdn.discordapp.com/attachments/316188085211627520/416674420329807892/Mr-Steven-and-fairing-detail-5-Pauline-Acalin-1024x1024.png)
(https://cdn.teslarati.com/wp-content/uploads/2018/02/Mr-Steven-and-fairing-detail-4-Pauline-Acalin.jpg)
Title: Re: Fairing reuse
Post by: Lar on 02/23/2018 07:06 pm
Those pics are so good with so many new details that someone is probably going to get the "you need to use tarps" memo :)
Title: Re: Fairing reuse
Post by: cppetrie on 02/23/2018 07:54 pm
They very clearly have a jig for cradling and securing the fairing half they recovered.
Title: Re: Fairing reuse
Post by: cebri on 02/23/2018 08:26 pm
Can you make out parts of the recovery system? I can only see 2 thrusters on the top of the fairing, guessing there is third on right side.
Title: Re: Fairing reuse
Post by: cscott on 02/23/2018 09:00 pm
Can you make out parts of the recovery system? I can only see 2 thrusters on the top of the fairing, guessing there is third on right side.
I've been looking for the parafoil. Presumably the steerable lines leading to the chute would be the most "interesting" part of the recovery hardware.
Title: Re: Fairing reuse
Post by: meekGee on 02/23/2018 09:46 pm
It has just occured to me that Mr. Steven catching the fairing has shades of McArthur catching the light-sail craft in the Mote.  Just random.

Sent from my R2 Plus using Tapatalk

Title: Re: Fairing reuse
Post by: Dao Angkan on 02/23/2018 10:58 pm
Sat on the supports under the net that were clearly visible prior to recovery. I guess that confirms that each half will be recovered by a separate boat.
Title: Re: Fairing reuse
Post by: Dao Angkan on 02/23/2018 11:01 pm
Can you make out parts of the recovery system? I can only see 2 thrusters on the top of the fairing, guessing there is third on right side.
I've been looking for the parafoil. Presumably the steerable lines leading to the chute would be the most "interesting" part of the recovery hardware.

The parafoil must release on "landing"? I guess that's the next thing to recover!
Title: Re: Fairing reuse
Post by: Bananas_on_Mars on 02/24/2018 06:33 am
Seems they're not bothering about reusing that fairing half, with the securing chain strung over the fairing without any protection...

I have the feeling that the fairing growth didn't go into growing the allowed payload space, but into beefing up the whole fairing for recovery. During the webcast at fairing deploy, it seemed the fairing behaved much stiffer than what i remember from previous launches.
Title: Re: Fairing reuse
Post by: guckyfan on 02/24/2018 08:42 am
http://www.der-orion.com/launch-log/2018/1515-falcon-9-bringt-paz-und-starlink-satelliten-in-den-orbit

This german language article claims with Fairing 2.0 the two halves are identical to the point that any two halves can be paired to one fairing. Is this a new information? It could be helpful when they expect a non negligible loss rate which seems likely given that wind plays a major role.
Title: Re: Fairing reuse
Post by: Bananas_on_Mars on 02/24/2018 09:02 am
http://www.der-orion.com/launch-log/2018/1515-falcon-9-bringt-paz-und-starlink-satelliten-in-den-orbit

This german language article claims with Fairing 2.0 the two halves are identical to the point that any two halves can be paired to one fairing. Is this a new information? It could be helpful when they expect a non negligible loss rate which seems likely given that wind plays a major role.

If you look at the recovered fairing, the parts of the 4 pushers look identical, and the locking mechanisms also seem identical, which in my opinion would mean they're not completely identical with regards to installed hardware (so there's still an active and a passive side), but that doesn't mean they can't be rebuilt by exchanging some of the hardware.
Title: Re: Fairing reuse
Post by: fthomassy on 02/24/2018 01:45 pm
http://www.der-orion.com/launch-log/2018/1515-falcon-9-bringt-paz-und-starlink-satelliten-in-den-orbit

This german language article claims with Fairing 2.0 the two halves are identical to the point that any two halves can be paired to one fairing. Is this a new information? It could be helpful when they expect a non negligible loss rate which seems likely given that wind plays a major role.
If you look at the recovered fairing, the parts of the 4 pushers look identical, and the locking mechanisms also seem identical, which in my opinion would mean they're not completely identical with regards to installed hardware (so there's still an active and a passive side), but that doesn't mean they can't be rebuilt by exchanging some of the hardware.
Looking at recent photos (https://twitter.com/w00ki33) from Pauline Acalin the two halves are very different . Pusher is male on broken half and female on other; seal material on broken and flat the other; anchors on broken and latch mechanism on other.

Edit: cebri posted those photos above already
Title: Re: Fairing reuse
Post by: JamesH65 on 02/24/2018 02:15 pm
http://www.der-orion.com/launch-log/2018/1515-falcon-9-bringt-paz-und-starlink-satelliten-in-den-orbit

This german language article claims with Fairing 2.0 the two halves are identical to the point that any two halves can be paired to one fairing. Is this a new information? It could be helpful when they expect a non negligible loss rate which seems likely given that wind plays a major role.

If you look at the recovered fairing, the parts of the 4 pushers look identical, and the locking mechanisms also seem identical, which in my opinion would mean they're not completely identical with regards to installed hardware (so there's still an active and a passive side), but that doesn't mean they can't be rebuilt by exchanging some of the hardware.

That would be my assumption. Keep the molded parts the same, ensure that fitting mounts are the same for male and female parts. That means only the fittings are handed, the CF stuff is ambidextrous.
Title: Re: Fairing reuse
Post by: AC in NC on 02/24/2018 04:34 pm
Hadn't thought to do the mental comparison before but the size of the fairing to the catcher's mitt is dramatic.  Feels even more like trying to hit a postage stamp than evoked simply from the magnitude of hitting a net on a ship from altitude.

Shorealone Films
https://www.flickr.com/photos/81789298@N05/26577016968/in/album-72157690782691332/

Makes me wonder about alternative net arrangements either using a larger footprint of "arms" for the net (of which there seems to be opportunity) or some kind of net vertical element that gives them an effectively longer target.

https://www.flickr.com/photos/81789298@N05/26577018358/in/album-72157690782691332/

I suppose one must presume they are comfortable that they can hit such a target.  Amazing accuracy given the relative sizes.
Title: Re: Fairing reuse
Post by: Comga on 02/24/2018 05:07 pm
There is an ongoing discussion in the Paz discussion thread about the coordination to catch  the descending fairing in the moving net on the ship. Several people use the analogy of outfielders catching fly balls. Some insight can be gained from the existing discussion on that very subject.

The outfielders don’t run to where the ball will land. They move to keep angles constant and angular rates down.
The same applied to intercepts like NASA’s Deep Impact. Once on the correct terminal trajectory the target appears fixed against the background.

For catching the fairing the ship doesn’t even have to be going at the same speed, although close might help.
As long as it can maneuver to keep the relative angle fixed the fairing will descend into the net.
Changes in descent rate have to be matched with changes in the speed of the boat.
Changes in direction also have to be chased.
Frankly I’m surprised that they missed by, what did they say, several hundred yards?
Title: Re: Fairing reuse
Post by: speedevil on 02/24/2018 05:53 pm
There is an ongoing discussion in the Paz discussion thread about the coordination to catch  the descending fairing in the moving net on the ship. Several people use the analogy of outfielders catching fly balls. Some insight can be gained from the existing discussion on that very subject.

The outfielders don’t run to where the ball will land. They move to keep angles constant and angular rates down.
The same applied to intercepts like NASA’s Deep Impact. Once on the correct terminal trajectory the target appears fixed against the background.

It really can't.
In usual cases, changes in wind are not wholly dominant on the motion of the ball.
Unpredicted wind changes can cause very, very large errors, as the windspeed approaches the (quite low) parafoil speed.
Title: Re: Fairing reuse
Post by: Space Ghost 1962 on 02/24/2018 07:58 pm
A better match for comparison would be an airdrop to shipboard. Which I've only seen once.

Some related work:
Precision Guided Airdrop for Vertical Replenishment
of Naval Vessels (https://calhoun.nps.edu/bitstream/handle/10945/35314/Seattle_Ships_Replenishment.pdf?sequence=1)

Shipboard Landing Challenges for Autonomous Parafoils (http://www.dtic.mil/get-tr-doc/pdf?AD=ADA548960)

Title: Re: Fairing reuse
Post by: Swedish chef on 02/24/2018 10:14 pm
I was thinking, if the net on Mr Steven proves to be a bit to small, why not step it up and use a similar construction on board a barge? I belive Of Course I Still Love You is 88*52 meters, if one make a similar construction that is on board Mr Steven could one perhaps get to 176*104 meter? Looking at the numbers for some of the automatic parachute landing system one starts to get close to the published landing accuracy on dry land. 
Title: Re: Fairing reuse
Post by: cscott on 02/24/2018 10:45 pm
I was thinking, if the net on Mr Steven proves to be a bit to small, why not step it up and use a similar construction on board a barge? I belive Of Course I Still Love You is 88*52 meters, if one make a similar construction that is on board Mr Steven could one perhaps get to 176*104 meter? Looking at the numbers for some of the automatic parachute landing system one starts to get close to the published landing accuracy on dry land.
Because the barge can't go fast enough.
Title: Re: Fairing reuse
Post by: Swedish chef on 02/24/2018 11:21 pm
Because the barge can't go fast enough.

I'm guessing one reason for a fast boat is because the landing area onboard is to small, so you make it up repositioning the boat. But if you work in the other direction and provide with a large enough landing area, that ought to be something worth considering. During this attempt did Mr Steven move to chase after the faring while it was falling? I haven't seen anything on that subject so i assume SpaceX can get enough precision to let the parachute navigate to the landing site, so perhaps with some tweaking a barge with a ridiculous large net might suffice.

On land i read that one of the parachute-system could land on a road some 40*200 meters wide. This might be achievable on a static barge.
Title: Re: Fairing reuse
Post by: LouScheffer on 02/24/2018 11:35 pm
Some interesting data on parafoils:   The US military, and presumably many others, has been looking at parafoils for quite some time.  We can use this to get an idea of what SpaceX might be facing.

Here's the data from the two parafoils that bracket SpaceX needs, from table 2, page 34, of "Unmanned Aircraft Systems"

                 mass         area       Wing loading   glide ratio  forward speed  vertical speed   turn rate
SPADeS     0.160 ton    34 m^2      5 kg/m^2       3.3            11.7  m/s     3.6 m/s           47o/sec
DragonFly  4.5 ton      325 m/s      14 kg/m^2      3.9            18.0  m/s     4.6 m/s           10o/sec

A SpaceX fairing half is guessed to mass about 2 tonnes.  So crudely interpolating, maybe a glide ratio of 3.8, a forward speed of 17 m/s, and a vertical speed of 4.5 m/s is practical.   

A forward speed of 17 m/s is equal to 33 knots.   So even in still air, Mr. Steven at 32 knots could almost keep up with the parafoil, and the payload could drop vertically into the net.  If there is any breeze at all, Mr. Steven could keep pace.

Of course mass constraints might force SpaceX to use a smaller, faster parachute.  Then the parafoil would overtake Mr. Stevens, at least in still air.  But the relative velocity could be quite small.

 
Title: Re: Fairing reuse
Post by: cscott on 02/25/2018 12:07 am
Because the barge can't go fast enough.

I'm guessing one reason for a fast boat is because the landing area onboard is to small, so you make it up repositioning the boat.

LouScheffer seems correct: the parafoil cannot hover, so the boat needs to match its forward speed as best it can or else that energy has to be taken out by the net.  The coincidence in parafoil speed and Mr. Steven's speed seems strong. Can't tow a barge nearly fast enough to make a meaningful contribution.

If the boat also needs to sprint to a computed landing target, you can't possibly make a net-on-barge as big as the distance Mr. Steven could sprint at 32kts even in the few minutes after parachute deploy.

32 knots = 16.462 meters per second. That's almost a kilometer in a single minute of descent time.

Title: Re: Fairing reuse
Post by: envy887 on 02/25/2018 12:16 am
Because the barge can't go fast enough.

I'm guessing one reason for a fast boat is because the landing area onboard is to small, so you make it up repositioning the boat.

LouScheffer seems correct: the parafoil cannot hover, so the boat needs to match its forward speed as best it can or else that energy has to be taken out by the net.  The coincidence in parafoil speed and Mr. Steven's speed seems strong. Can't tow a barge nearly fast enough to make a meaningful contribution.

If the boat also needs to sprint to a computed landing target, you can't possibly make a net-on-barge as big as the distance Mr. Steven could sprint at 32kts even in the few minutes after parachute deploy.

But it can target a fixed location to within a certain positional error. Just have t make sure the positional error is smaller than the landing area.
Title: Re: Fairing reuse
Post by: aero on 02/25/2018 01:21 am
Because the barge can't go fast enough.

I'm guessing one reason for a fast boat is because the landing area onboard is to small, so you make it up repositioning the boat.

LouScheffer seems correct: the parafoil cannot hover, so the boat needs to match its forward speed as best it can or else that energy has to be taken out by the net.  The coincidence in parafoil speed and Mr. Steven's speed seems strong. Can't tow a barge nearly fast enough to make a meaningful contribution.

If the boat also needs to sprint to a computed landing target, you can't possibly make a net-on-barge as big as the distance Mr. Steven could sprint at 32kts even in the few minutes after parachute deploy.

32 knots = 16.462 meters per second. That's almost a kilometer in a single minute of descent time.

That's nice, but the boat is massive, it is not a dragster. How much time do you suppose it would take for Mr. Stevens to get up to speed? And that is assuming that he/she is headed in the right direction to begin with. (Probably a viable assumption.)

I didn't find any answers using Google but I expect that mass and power are needed.
Title: Re: Fairing reuse
Post by: OneSpeed on 02/25/2018 01:36 am
But it can target a fixed location to within a certain positional error. Just have t make sure the positional error is smaller than the landing area.

Yes, although the Falcon fairing landing algorithm will need to target a moving location. The simplest case of that would be to target a location moving at a constant speed and direction. Taking a standard parachute landing pattern as an example, skydivers typically fly a pattern similar in form to that used by aircraft. The pilot of a side by side dual control aircraft typically sits in the port (left) seat, and so for maximum visibility will fly a left handed landing pattern. The pattern consists of downwind, crosswind and final legs. To account for any dispersions of the flight path by changes in wind speed or direction, the pilot can vary the arc of the pattern to control sink rate. SpaceX may even extend this concept to a much higher altitude, and fly a spiral descent to the landing pattern.

http://goo.gl/HphfWa
Title: Re: Fairing reuse
Post by: aero on 02/25/2018 02:45 am
I recall that one of the useful capabilities of certain GPS systems is "time on target." That is, it will guide you to be exactly where you want to be at the exact time you want to be there (subject to GPS limitations of course).  If both the parasail and Mr. Stevens used such a system then perhaps the catching problem would be solved. It then boils down to environmental uncertainty, wind gusts, wave height and the like.
Title: Re: Fairing reuse
Post by: Hobbes-22 on 02/25/2018 06:55 am

That's nice, but the boat is massive, it is not a dragster. How much time do you suppose it would take for Mr. Stevens to get up to speed? And that is assuming that he/she is headed in the right direction to begin with. (Probably a viable assumption.)


From standstill to top speed, count on about a minute.
Title: Re: Fairing reuse
Post by: jilmari on 02/25/2018 11:18 am
I think the obvious solution would be to catch both parachutes in tow by smaller boats before landing them on the deck of the mother ship. Two larger Zodiacs would do. Big ram air canopies are fairly stable and can be towed without any modifications. The forces involved are not huge, so the weight of some 500m long string shouldn't be an issue.

After the catch, fairings could be held airborne indefinitely, or as long as fuel lasts. In the tow parachutes would not be individual flight vehicles but essentially kites and could be pinpointed to the deck. If the brake lines of the parachute could be controlled remotely, that would help even more. After the first fairing had been secured, take your time, no need to hurry here, the second boat which had been in waiting pattern, would bring the another one in.

Lift up the boats and head home!
Title: Re: Fairing reuse
Post by: cscott on 02/25/2018 01:27 pm


I think the obvious solution would be to catch both parachutes in tow by smaller boats before landing them on the deck of the mother ship.

This is a "Rube Goldberg" solution that isn't immediately dismissible as crazy. Thanks!

Some number crunching would help determine how reasonable this is:

1) how long a "kite string" is reasonable to deploy at altitude, and how vertical could it be kept w/ a reasonable ballast weight on the end? ("Effective length")

2) what's the descent rate of the fairing; then how long would it take to descend the length of the kite string? ("Max capture time" = effective length / descent rate).  If the fairing is updating its target point on the fly, then "max capture time" is the time between the fairing being able to reasonably accurately predict its target location and the time it hits the water.

3) how much faster is a zodiac (or hydrofoil cigarette boat) than Mr. Steven? ("Differential speed")

4) How much *more* distance could the fast boat cover in the chase time available? (Differential speed * Max capture time)

From that you can reduce the idea to meters: using a kite string would expand the possible landing zone by the distance in (4), at a weight penalty of not-less-than the kite string weight plus the ballast weight. For more realism, you might have to subtract some portion of "kite string length * sin(fall angle)" to account for the extra distance the fast boat would have to travel to compensate for any unpredictability in the direction the kite string is blown back.

The idea is not obviously crazy, but my intuition is that it falls down on calculation (1) (it's hard to get a long enough kite string to fall straight enough down in order to make this worthwhile) or calculation (3) (the fastest boat is not that much faster than Mr. Steven, since hydrodynamic drag scales up quickly).

Put another way, how much advance warning did they have that the PAZ fairing was going to land 100 meters off?  Was this a last minute wind gust, or did they know enough in advance that they could have sent a faster boat to the target location in time?
Title: Re: Fairing reuse
Post by: aero on 02/25/2018 05:36 pm
I recall that one of the useful capabilities of certain GPS systems is "time on target." That is, it will guide you to be exactly where you want to be at the exact time you want to be there (subject to GPS limitations of course).  If both the parasail and Mr. Stevens used such a system then perhaps the catching problem would be solved. It then boils down to environmental uncertainty, wind gusts, wave height and the like.

I'm surprised that this post didn't get any traction. Parasails can be landed by a human pilot with very good accuracy.

https://www.google.com/search?q=parasailing+landing+accuracy+images&tbm=isch&tbo=u
&source=univ&sa=X&ved=0ahUKEwjb1qHV0sHZAhVY5mMK
HduTDvAQ7AkIQg&biw=1855&bih=959#imgrc=iD9hqrgNTUgd0M: (https://www.google.com/search?q=parasailing+landing+accuracy+images&tbm=isch&tbo=u
&source=univ&sa=X&ved=0ahUKEwjb1qHV0sHZAhVY5mM
KHduTDvAQ7AkIQg&biw=1855&bih=959#imgrc=iD9hqrgNT
Ugd0M:)


The question then is, "How close can an automated parasail control system come to landing with human accuracy?"

Note that accuracy of two identical GPS systems, even cheap ones, one on Mr. Stevens and one on the fairing would be almost perfect, the solutions will be the same within millimeters. That is because identical GPS receivers in near the same location will select the same GPS satellite signals, crunch the numbers using identical algorithms, achieve the same absolute errors and hence even if the touchdown point is offset from the planned time and target location, both systems will calculate the same offset. Hence the parasail and Mr. Stevens will arrive at the same location at the same time. The absolute error may be large but the relative error will be minuscule. If you happen to have two identical GPS receivers you can test this by turning them on, side by side and note that they calculate the same location, whether that location is precisely correct or not is immaterial.

The question then is, "How close can an automated parasail control system come to landing with human accuracy?"

The time on target should be a fixed time from lift-off so communicating lift-off time to Mr. Stevens might be needed if there was a hold during the launch window. The flight computers would communicate lift-off time to the parasail control system so that's easy.

With this system, it might be so simple as having Mr. Stevens station keep like the barges do. That is, why make the touchdown algorithms more complicated than necessary?

So, can an automated parasail flight control system be carried on the fairing that has reasonable accuracy, sufficient to land in the net?
Title: Re: Fairing reuse
Post by: cscott on 02/25/2018 05:45 pm


So, can an automated parasail flight control system be carried on the fairing that has reasonable accuracy, sufficient to land in the net?

So far: no.

But maybe next time!
Title: Re: Fairing reuse
Post by: Chris Bergin on 02/25/2018 06:05 pm
FEATURE ARTICLE: SpaceX's Mr. Steven, the FSV fairing catcher -

https://www.nasaspaceflight.com/2018/02/spacexs-mr-steven-fsv-fairing-catcher/

- By Micheal Baylor

It includes an interview with Brian Herbert, a Senior Dynamic Positioning Officer who interacted with Mr. Steven before SpaceX leased her. Mr. Steven is a very capable ship!
Title: Re: Fairing reuse
Post by: aero on 02/25/2018 06:28 pm


So, can an automated parasail flight control system be carried on the fairing that has reasonable accuracy, sufficient to land in the net?

So far: no.

Well, there is no doubt that you are correct.

Quote
But maybe next time!

That will always be true until successful. After that, the answer will be "Yes."
Title: Re: Fairing reuse
Post by: flyright on 02/25/2018 07:26 pm
Have there been any clues yet as to how the fairing was pulled out of the water onto Mt Steven's deck?
Could that have been done using winches alone?
I don't see any evidence of a crane on Mr Steven.
Title: Re: Fairing reuse
Post by: speedevil on 02/25/2018 07:35 pm
Have there been any clues yet as to how the fairing was pulled out of the water onto Mt Steven's deck?
Could that have been done using winches alone?
I don't see any evidence of a crane on Mr Steven.

The sea looked fairly calm, Mr Steven is very, very manoeverable.
The base of the fairing is pretty close to sea level, it may have been as simple as back up to the fairing, drop the dinghy over the side, motor over to the fairing, tie on a rope, and then winch it in, with some padding to protect the edge of the fairing.
Even without any special hardware.

it might even have been reachable safely to rope from Mr Stevens deck.

There are lots of winches onboard, and they were quite able to get the other fragment on deck.

Recovery of bits of fairing has been done before with other boats they own, it is not particularly difficult getting an intact one on the boat, in the sea state they were in, in comparison to fishing out small bits floating at odd angles.
Title: Re: Fairing reuse
Post by: DistantTemple on 02/25/2018 07:43 pm
The arms are strong enough to hold the faring as it lands, and restrain its motion, so they will be strong enough to support its weight if used as a simple crane. Using blocks and tackle from adjacent arms either alongside or at the rear, the faring half could be lifted, then hauled aboard... using winches. Messy but in keeping with "fishing for fairings"!, and also in keeping with the skills of a "fast supply boat" crew. It's also something that would/should have been anticipated, and therefore planned for.
Title: Re: Fairing reuse
Post by: Steve D on 02/26/2018 12:02 am
I think one of the biggest problems is going to be how random the reentry path will be for the fairing. A shape like this is going to flutter alot..... and as it flutters it is going dart in a chaotic manor in random directions. This could mean the area it could end up in during any given launch could be wider then the parafoils range. This is nothing like the booster that can be guided the whole way. More like a skydiver with a bad spot.....


I think their best bet for now is to build a "marine grade" fairing and let it soft land in the water and recover with the boat. Even if they do manage to catch one in mid air its still going to get soaked by spray on the way back.
Title: Re: Fairing reuse
Post by: rst on 02/26/2018 12:26 am
I'm surprised that this post didn't get any traction. Parasails can be landed by a human pilot with very good accuracy.

https://www.google.com/search?q=parasailing+landing+accuracy+images&tbm=isch&tbo=u
&source=univ&sa=X&ved=0ahUKEwjb1qHV0sHZAhVY5mMK
HduTDvAQ7AkIQg&biw=1855&bih=959#imgrc=iD9hqrgNTUgd0M: (https://www.google.com/search?q=parasailing+landing+accuracy+images&tbm=isch&tbo=u
&source=univ&sa=X&ved=0ahUKEwjb1qHV0sHZAhVY5mM
KHduTDvAQ7AkIQg&biw=1855&bih=959#imgrc=iD9hqrgNT
Ugd0M:)


The question then is, "How close can an automated parasail control system come to landing with human accuracy?"

And if humans do have any kind of advantage, it might be possible for a human on the boat to manage the last stages of descent by radio control, once they've got line of sight.
Title: Re: Fairing reuse
Post by: aero on 02/26/2018 02:51 am
I'm surprised that this post didn't get any traction. Parasails can be landed by a human pilot with very good accuracy.

https://www.google.com/search?q=parasailing+landing+accuracy+images&tbm=isch&tbo=u
&source=univ&sa=X&ved=0ahUKEwjb1qHV0sHZAhVY5mMK
HduTDvAQ7AkIQg&biw=1855&bih=959#imgrc=iD9hqrgNTUgd0M: (https://www.google.com/search?q=parasailing+landing+accuracy+images&tbm=isch&tbo=u
&source=univ&sa=X&ved=0ahUKEwjb1qHV0sHZAhVY5mM
KHduTDvAQ7AkIQg&biw=1855&bih=959#imgrc=iD9hqrgNT
Ugd0M:)


The question then is, "How close can an automated parasail control system come to landing with human accuracy?"

And if humans do have any kind of advantage, it might be possible for a human on the boat to manage the last stages of descent by radio control, once they've got line of sight.

I don't know that the above link to Google search results shows the images I wanted. It no longer does for me. This is the direct link to the site with the images that I wanted to show:

http://blog.performancedesigns.com/pd-accuracy-team-jumpers-cheryl-stearns-and-james-hayhurst-traded-first-place-medals-in-accuracy-competition-at-archway-skydi/ (http://blog.performancedesigns.com/pd-accuracy-team-jumpers-cheryl-stearns-and-james-hayhurst-traded-first-place-medals-in-accuracy-competition-at-archway-skydi/)

Title: Re: Fairing reuse
Post by: garcianc on 02/26/2018 02:53 am
I think the obvious solution would be to catch both parachutes in tow by smaller boats before landing them on the deck of the mother ship.
I posted a similar idea on page 53 of this thread. It makes a lot of sense to me, even if just to buy some time. By the way, a spool of 5,000 ft of paracord only weights 30 lbs according to Amazon.com (just a point of reference, not saying that would be the actual tow line).

Here is a paper proposing a related method, except this one is for delivering cargo from a ship to shore using a towed parasail: http://www.dtic.mil/get-tr-doc/pdf?AD=ADA521413
Title: Re: Fairing reuse
Post by: AC in NC on 02/26/2018 03:05 am
I think one of the biggest problems is going to be how random the reentry path will be for the fairing. A shape like this is going to flutter alot..... and as it flutters it is going dart in a chaotic manor in random directions. This could mean the area it could end up in during any given launch could be wider then the parafoils range. This is nothing like the booster that can be guided the whole way. More like a skydiver with a bad spot.....


I think their best bet for now is to build a "marine grade" fairing and let it soft land in the water and recover with the boat. Even if they do manage to catch one in mid air its still going to get soaked by spray on the way back.

The former is unlikely given the results to date.  The latter is unlikely as it would have likely have already been the direction if possible.
Title: Re: Fairing reuse
Post by: obi-wan on 02/26/2018 04:37 am
I think one of the biggest problems is going to be how random the reentry path will be for the fairing. A shape like this is going to flutter alot..... and as it flutters it is going dart in a chaotic manor in random directions. This could mean the area it could end up in during any given launch could be wider then the parafoils range. This is nothing like the booster that can be guided the whole way. More like a skydiver with a bad spot.....


I think their best bet for now is to build a "marine grade" fairing and let it soft land in the water and recover with the boat. Even if they do manage to catch one in mid air its still going to get soaked by spray on the way back.

"Flutter" is aeroelastic instability - for example, divergent torsional oscillation of a wingtip. Without prompt action (usually including reducing the flight speed), flutter generally causes in-flight breakups. I suspect you're talking about a rigid-body mode, either cyclical due to trailing vortex shedding, or more chaotic due to higher-order effects. I don't know if there's an accepted term for that kind of motion, other than the descriptive "falling leaf" example.
Title: Re: Fairing reuse
Post by: aero on 02/26/2018 05:04 am
By reviewing what we know about the fairing recovery efforts to date, what are the constraints that SpaceX is working with?

They don't want it to get wet - implies that it would be too much time and expense to refurbish,
They ruled out using an ASDS as a recovery vessel - implies that the fairing trajectory is too unpredictable to hit a fixed target,
What else have they ruled out, being much closer to the problem than we are - (Sometimes being too close is the problem).

So they now have fairing-2 that comes close to the target, missed by a few 100 meters. With Mr. Stevens sprint speed and I assume a good radar set, how much time would Mr. Stevens have to sprint toward the touchdown point? Only a very few minutes (5 min?) which gives a circular error window of what, about 6 nautical miles? The Dragon capsules routinely splash down much closer to the recovery ship than that. To me, that means the problem is trying to guide that "Fluffy" fairing through the unpredicted atmospheric winds and turbulence. In other words, they need more control authority on the fairing/parasail system. I assume that they have available all the control authority that the parasail can provide. A bigger parasail will give more time for Mr. Stevens to sprint, increasing the circular error window, but will it provide more control authority or will it simply allow the winds to carry the fairing/parasail further away? Or perhaps the fairing/parasail doesn't have a guidance and control system at all?

Speculation anyone?


Title: Re: Fairing reuse
Post by: kenny008 on 02/26/2018 09:42 am
It seems like Mr. Steven would have to trail slightly behind the capture point. In the last minute or so, if the sail suddenly drifted to port or stbd a bit, she would not be able to quickly sprint sideways. You might want to trail the capture point to have the ability to quickly turn in the last minute to get under it, then a quick sprint to the final
capture location.
In the last minute, you are much more constrained in lateral positioning ability. You have much more control fore and aft.
Title: Re: Fairing reuse
Post by: nicp on 02/26/2018 09:51 am
Surely it would be easier to snag the fairing's parachute from a helicopter. I concede that being hundreds of miles from land could be a problem.
Title: Re: Fairing reuse
Post by: JamesH65 on 02/26/2018 11:13 am
Last effort was a few hundred metres away.

Musk said a bigger parafoil was required.

Implies they didn't quite have enough time to get the boat in the right place, not that steering was an inherent issue.



My thoughts of not dropping it in the water are less to do with waterproofing, than damage caused in rough seas, perhaps even making recovery from the water impossible.

Title: Re: Fairing reuse
Post by: symbios on 02/26/2018 12:48 pm
I wonder if the fairing continually are sending its updated estimated landing point to the ship, or if the ship manually by using the old Mk 1 Eyeball has to estimate the landing position offset from a preset landing position...

I wonder how accurately a parafoil is able to estimate its landing position during descent. This in contrast how accurate it is to hitting a preprogrammed landing point. This makes a big difference in the approach to take to catching it. :)
Title: Re: Fairing reuse
Post by: ChrisC on 02/26/2018 01:30 pm
For those of you posting questions and ideas today (above), it sounds like you're new here because these have been discussed at length in the past.  I'd recommend going back in this thread, waaaay back, and just reading through.  Some of the questions above have been posed (and discussed at length) in just the past week, but I'd suggest going all the way back to page 1 and gorging on the whole discussion.  Lots of ground has already been covered.  And the experts who weighed in over the years may not happen to pass by here today and provide that answer again.
Title: Re: Fairing reuse
Post by: TakeOff on 02/26/2018 03:23 pm
The fairing is the womb of a launcher.
The BIG value of reusing fairings lies in making them very much more protective of the precious payload (dampening vibrations and what have you). That concept might simplify the design of the customers' billion dollar satellites by an order of magnitude more than just saving some of the costs of today's fairings.
Title: Re: Fairing reuse
Post by: Jim on 02/26/2018 05:02 pm

The BIG value of reusing fairings lies in making them very much more protective of the precious payload (dampening vibrations and what have you).

No, they don't do that nor can they.
Title: Re: Fairing reuse
Post by: OnWithTheShow on 02/26/2018 06:23 pm

The BIG value of reusing fairings lies in making them very much more protective of the precious payload (dampening vibrations and what have you).

No, they don't do that nor can they.

Ummmm

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150022130.pdf
Title: Re: Fairing reuse
Post by: Jim on 02/26/2018 06:33 pm

The BIG value of reusing fairings lies in making them very much more protective of the precious payload (dampening vibrations and what have you).

No, they don't do that nor can they.

Ummmm

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20150022130.pdf


That is acoustics and not vibrations, which come through the adapter.
Title: Re: Fairing reuse
Post by: OnWithTheShow on 02/26/2018 06:51 pm
The foam is there to reduce acoustic vibrations, which I gather is what the poster above meant.
Title: Re: Fairing reuse
Post by: AC in NC on 02/26/2018 07:24 pm
The foam is there to reduce acoustic vibrations, which I gather is what the poster above meant.

The poster raised the potential for an order of magnitude "simplification" in the design of billion dollar satellites and that the "BIG Value" of fairing reuse derives from being able to invest in more advanced fairings that could enable such simplification because the investment would be justified by recovery.

That's ridiculous.
Title: Re: Fairing reuse
Post by: Jim on 02/26/2018 07:38 pm
The foam is there to reduce acoustic vibrations, which I gather is what the poster above meant.

Most fairings have some kind acoustic damping material/foam already.  Reuse would mean this would have to be more rugged or the fairing itself provide the damping.
Title: Re: Fairing reuse
Post by: OnWithTheShow on 02/27/2018 01:48 am
The foam is there to reduce acoustic vibrations, which I gather is what the poster above meant.

Most fairings have some kind acoustic damping material/foam already.  Reuse would mean this would have to be more rugged or the fairing itself provide the damping.

On that note it sure looked like the SpaceX fairing lost all its foam which is understandable. I have a strong knowledge of traditional earth bound acoustic foam which while expensive in the audio studio and theatrical world is pretty cheap in the aerospace world. Any idea if aerospace acoustic foam is of a similiar price? If it is I don't see why they would need to upgrade the foam/dampening to withstand reentry and landing. Just reinstall after each flight.
Title: Re: Fairing reuse
Post by: Hobbes-22 on 02/27/2018 08:51 am
Some fairings (e.g. for Ariane 5) use Helmholz resonators (maybe in addition to foam, not sure).

The FH fairing seems to be intact, the black panels on the inside look like foam to me.
Title: Re: Fairing reuse
Post by: Johnnyhinbos on 02/27/2018 03:44 pm
Some fairings (e.g. for Ariane 5) use Helmholz resonators (maybe in addition to foam, not sure).

The FH fairing seems to be intact, the black panels on the inside look like foam to me.
Where did you see the FH fairing?
Title: Re: Fairing reuse
Post by: matthewkantar on 02/27/2018 04:26 pm
There were a many photos out before the launch.
Title: Re: Fairing reuse
Post by: Johnnyhinbos on 02/27/2018 04:55 pm
There were a many photos out before the launch.
I was asking about the "FH fairing seems intact" bit. I wasn't aware we'd seen photos of a FH recovered fairing...
Title: Re: Fairing reuse
Post by: AC in NC on 02/27/2018 05:42 pm
There were a many photos out before the launch.
I was asking about the "FH fairing seems intact" bit. I wasn't aware we'd seen photos of a FH recovered fairing...

https://www.teslarati.com/spacex-recovered-fairing-spotted-mr-steven-boat/


https://forum.nasaspaceflight.com/index.php?topic=44892.180
https://www.nasaspaceflight.com/2018/02/spacexs-mr-steven-fsv-fairing-catcher/
Title: Re: Fairing reuse
Post by: Johnnyhinbos on 02/27/2018 05:44 pm
There were a many photos out before the launch.
I was asking about the "FH fairing seems intact" bit. I wasn't aware we'd seen photos of a FH recovered fairing...

https://www.teslarati.com/spacex-recovered-fairing-spotted-mr-steven-boat/
I guess I’m not being clear...

I wasn’t aware that the FALCON HEAVY fairings were recovered...
Title: Re: Fairing reuse
Post by: AC in NC on 02/27/2018 06:02 pm
I guess I’m not being clear...

I wasn’t aware that the FALCON HEAVY fairings were recovered...

Sorry.  Total tunnel vision because of the foam discussion.  Certainly a mistaken qualification from the original commenter.
Title: Re: Fairing reuse
Post by: OxCartMark on 02/28/2018 12:04 am
There's a very high level phenomenon that is very significant to this discussion that I'm surprised hasn't come up in 73 pages - Downplaning.  At least that's the term that's used for the phenomenon in the paragliding community.  We need to bring that into any discussion of targeting accuracy and landing timing.  Discussion so far has only talked of the controllability of the fairing horizontally as if this were a sailplane landing (something else I have experience with) but its not that.  With a parafoil drag on the suspended load changes pitch and thus rate of descent.  Not just transiently as you might think on first inspection but it changes pitch continuously.  And not just a little.  I've seen it where the drag on the load (me + a round parachute significantly smaller than the parafoil wing) was so great that the parafoil pitched nearly vertical and contributed nearly no lift - not transiently but on an ongoing basis.  Now add in that with a fairing the drag value may be changing if the fairing is allowed to rotate or flutter.  Sure, you can attach your parafoil to one point or bridle attachment points to get it to fly predominantly into the relative wind but I think most of the ways you'd do that would either cause the fairing to not land convex down and parallel with the net or would use a drogue chute to stabilize the fairing flutter, said drogue just adding drag and adding to the downplaning.  So how significant is the area of the fairing?  Well, let's try some rough numbers...

Fairing area
Side Area: 5m x 20m = 100m^2
Frontal Area: (2.5m)^2 * Pi = 20m^2
   That's a 5:1 ratio that may be in play if the fairing is allowed to flutter under the canopy

What size parafoil would be used?
Load - 1000kg. (?)
Wing loading for my paraglider: 100kg / 26m^2  = 3.8kg / m^2
Wing loading for at typical sport parachute (Google): 5.5kg / m^2
      Averaging paraglider and parachute: 4.6kg / m^2
1000kg / (4.6kg / m^2) = 215m^2 parafoil area

So the area of the load seems to be 9-46% of the parafoil area.  Seems quite likely to have a significant downplaning issue to me.  Perhaps if varying between 9% and 46% an unpredictably varying amount of downplaning.

I'll leave this as an exercise for those so inclined:  Assume a l/d ratio for the parafoil (paraglider ~8:1, parachute ?3:1?), create free body diagrams and descent angles for the fairing under a parafoil with the assumption that the pitch is based on the l/d and the angle at which the total load is applied to the hanging point.

---topic change---

I think the two posters that proposed fast boats to tow the fairing until its landed on on a larger boat had it right.  Very right.  I've thought the same (having been towed by boats as a way to launch paragliders) and may have (probably not) posted as much.  But I want to add some thoughts to that method.  First, the tow line wouldn't need to be large or have much drag as was speculated earlier.  Spectra and various other high tech lines can have miniscule cross sections.  The spectra we typically use to tow has a breaking load of 500kg. and a cross sectional area (when not in tension) similar to that of the lead in a wood pencil.  Second, the line could be attached to the nose of the fairing so that tow tension would align it to to the tow direction and remove any randomness to its orientation, third, in the final moments of the tow as the fairing closed in on the deck of the recovery boat I assume a winch on the cigarette boat would have reeled in the fairing (on a short leash) so that any side to side deviation would have some correction applied by the short leash being pulled somewhat sideways.
Title: Re: Fairing reuse
Post by: Hobbes-22 on 02/28/2018 09:32 am
Some fairings (e.g. for Ariane 5) use Helmholz resonators (maybe in addition to foam, not sure).

The FH fairing seems to be intact, the black panels on the inside look like foam to me.
Where did you see the FH fairing?

Brainfart. Should have been the PAZ fairing.
Title: Re: Fairing reuse
Post by: OneSpeed on 02/28/2018 10:13 am
I think the two posters that proposed fast boats to tow the fairing until its landed on on a larger boat had it right.  Very right.

An interesting post, and it may well be possible for a cigarette boat to tow a Falcon 9 fairing under a parafoil at 32 knots, but are you implying SpaceX has actually attempted this? Do you have evidence that a cigarette or similar fast boat accompanied Mr Steven in the recent PAZ fairing recovery attempt?
Title: Re: Fairing reuse
Post by: Johnnyhinbos on 02/28/2018 11:58 am
I think the two posters that proposed fast boats to tow the fairing until its landed on on a larger boat had it right.  Very right.

An interesting post, and it may well be possible for a cigarette boat to tow a Falcon 9 fairing under a parafoil at 32 knots, but are you implying SpaceX has actually attempted this? Do you have evidence that a cigarette or similar fast boat accompanied Mr Steven in the recent PAZ fairing recovery attempt?
People who propose schemes like this don’t understand the meaning of “offshore” or ocean going. Simply not feasible. Could you put a small go-fast boat out there under ideal conditions? Sure - but that’s the exception and very far from the norm.
Title: Re: Fairing reuse
Post by: LouScheffer on 02/28/2018 12:24 pm
There's a very high level phenomenon that is very significant to this discussion that I'm surprised hasn't come up in 73 pages - Downplaning.  At least that's the term that's used for the phenomenon in the paragliding community.  We need to bring that into any discussion of targeting accuracy and landing timing.  Discussion so far has only talked of the controllability of the fairing horizontally as if this were a sailplane landing (something else I have experience with) but its not that.  With a parafoil drag on the suspended load changes pitch and thus rate of descent.  [...]

I agree with the concern and think this is why the ship will match the forward speed of the parafoil.  In this case the fairing is approaching the net vertically (in the ship/parafoil frame) and variations in the rate of descent do not matter.  They affect only the arrival time, and not the odds of hitting the net.  Of course the thrashing of the fairing will also affect the forward speed somewhat, but this is the easiest parameter for the ship to change as it chases the fairing.

Basically the fairing tries to fly straight and as stably as possible, while the ship tries to stay directly under the descending fairing.  When they get close, each side may do some last second corrections.
Title: Re: Fairing reuse
Post by: OxCartMark on 02/28/2018 01:08 pm
There's a very high level phenomenon that is very significant to this discussion that I'm surprised hasn't come up in 73 pages - Downplaning.  At least that's the term that's used for the phenomenon in the paragliding community.  We need to bring that into any discussion of targeting accuracy and landing timing.  Discussion so far has only talked of the controllability of the fairing horizontally as if this were a sailplane landing (something else I have experience with) but its not that.  With a parafoil drag on the suspended load changes pitch and thus rate of descent.  [...]

I agree with the concern and think this is why the ship will match the forward speed of the parafoil.  In this case the fairing is approaching the net vertically (in the ship/parafoil frame) and variations in the rate of descent do not matter.  They affect only the arrival time, and not the odds of hitting the net.  Of course the thrashing of the fairing will also affect the forward speed somewhat, but this is the easiest parameter for the ship to change as it chases the fairing.

Basically the fairing tries to fly straight and as stably as possible, while the ship tries to stay directly under the descending fairing.  When they get close, each side may do some last second corrections.
If there is thrashing of the fairing I think most people perceive its effect to be manifested solely as drag acting to slow it but I think the bigger factor that would come from thrashing would be changes in the glide slope angle.

Does anyone know if the parachute guidance system they are using controls using only brakes lines attached to the rear of the parafoil (as parachutes would be steered) or if they have what I'll call four channel control capable of varying also the relative length of the front and rear risers?
Title: Re: Fairing reuse
Post by: cscott on 02/28/2018 02:18 pm


Does anyone know if the parachute guidance system they are using controls using only brakes lines attached to the rear of the parafoil (as parachutes would be steered) or if they have what I'll call four channel control capable of varying also the relative length of the front and rear risers?

That's what I was hoping to see on the recent pictures of the recovered fairing, but it didn't seem as though anyone was able to identify exactly where the parafoil attached, or where the line-cutting mechanisms we're, since it appeared the parafoil detached before the picture of the fairing floating in the water was taken.

That said, I'd be surprised if they didn't actuate all of the risers: the compute and electromagnetics required have got to be relatively small, cheap, and lightweight compared to the fairing and parafoil.
Title: Re: Fairing reuse
Post by: deruch on 03/01/2018 09:50 am
Wrt "pristine" looking fairings: most of the blackening on returned stages is soot blown backwards from the landing and reentry burns (and mostly from engine startup it appears).  There's a great clip of video from one of the most recent RTLS landings where you can see the stage blackening as the burn starts.  The FH boosters also got toasted on top from flying through the center stage exhaust.

Given that the fairings do not have Merlins to ignite, they should look pristine so long as they manage to avoid the S2 exhaust plume---and good separation distance from S2 is pretty much their only job.  (In footage you can see them fall well off to the side of the stage.)

While they likely don't get quite the blasting that, say, the interstage gets after stage separation and SES-1, the inside of the fairing halves probably do get some deposition of exhaust from the MVac as they fall past.  With so little pressure at that altitude, the exhaust expands a lot and the fairings fall right through it.  Whether that contamination is significant or not remains to be seen, but wasn't something I had considered before.  Thanks.
Title: Re: Fairing reuse
Post by: LouScheffer on 03/01/2018 11:52 am
Here's a perhaps relevant video I previously posted on the PAZ thread, of a parachutist landing on a moving truck.  He guides himself to roughly the right spot, going in circles to do so, then he and the truck both line up on final.   The truck then drives straight and a little slower than the forward speed of the parachute.  He hits a spot which is maybe 2 meters wide by 5 meters long.
Parachutist landing on moving truck (https://www.youtube.com/watch?v=1OzoB5kwQ3Q)
Title: Re: Fairing reuse
Post by: Nomadd on 03/01/2018 03:00 pm
 I haven't worked on any rocket fairings, but I have put a lot of radar and comms gear on ships. The grief that would ensue from the beast hitting the top of the bridge is no small thing. They'd probably end up towing the boat in with the radars damaged. And even as light and fluffy as that fairing structure is, the safety aspects of trying to get your boat under a large falling object like that seem to be getting glossed over. Little squalls, or the ocean equivalent of dust devils come out of nowhere all the time.
 There's no bigger SpaceX supporter than me, but this whole setup just seems like a bad idea. Maybe if the net covered the whole ship.
Title: Re: Fairing reuse
Post by: AC in NC on 03/01/2018 03:12 pm
Maybe if the net covered the whole ship.

I was envisioning the net rising dramatically in the front quadrant something like a baseball backstop excluding the "lip" folded back over.  Seems like it would provide some useful margin in a number of ways.
Title: Re: Fairing reuse
Post by: VAB67 on 03/01/2018 03:16 pm
what happens to the other faring?
Title: Re: Fairing reuse
Post by: cscott on 03/01/2018 04:38 pm
Maybe if the net covered the whole ship.

I was envisioning the net rising dramatically in the front quadrant something like a baseball backstop excluding the "lip" folded back over.  Seems like it would provide some useful margin in a number of ways.
There is some structure that's been added to the front, between the net and the bridge.  I don't know it's exact purpose, but it's obviously new if you compare SeaTran's photos of the unmodified Mr. Steven.
Title: Re: Fairing reuse
Post by: deruch on 03/01/2018 04:45 pm
Maybe if the net covered the whole ship.

I was envisioning the net rising dramatically in the front quadrant something like a baseball backstop excluding the "lip" folded back over.  Seems like it would provide some useful margin in a number of ways.
There is some structure that's been added to the front, between the net and the bridge.  I don't know it's exact purpose, but it's obviously new if you compare SeaTran's photos of the unmodified Mr. Steven.

It looks like it's so that they can run the forward stays down in front of the bridge. 
Title: Re: Fairing reuse
Post by: cscott on 03/01/2018 04:46 pm
what happens to the other faring?
Surfboard.

( http://www.abbygarrett.com/comics/ )
Title: Re: Fairing reuse
Post by: Swoopert on 03/01/2018 09:15 pm
There's a very high level phenomenon that is very significant to this discussion that I'm surprised hasn't come up in 73 pages - Downplaning.  At least that's the term that's used for the phenomenon in the paragliding community.  We need to bring that into any discussion of targeting accuracy and landing timing.

I don't believe that this will have been a major issue, which is borne out by the success so far.

For info, freefall ram-air parachutes can be loaded anywhere up from 2.5 kg/m2 to very highly loaded (such as mine which are at 15 kg/m2 - hence he nickname/username). The lower loaded canopies tend to have lower aspect ratios and be more stable, but obviously far less horizontal airspeed. The heavier loaded canopies tend to have higher aspect ratuos, will have a faster forward speed, but their stability will be disproportionately affected by the drag of the payload. Obviously there is a balancing act in the middle where SpaceX have found the "sweet spot".
Title: Re: Fairing reuse
Post by: OxCartMark on 03/06/2018 03:22 am
I don't believe that this will have been a major issue, which is borne out by the success so far.

No success so far.
Far from success.
Hundreds of yards.
So nothing borne out.
Something in the current approach seems to may be a major issue.
Title: Re: Fairing reuse
Post by: Hobbes-22 on 03/06/2018 08:14 am
How many fairing recovery attempts have been made so far? A bit too early to conclude there's a 'major issue', IMO.
Title: Re: Fairing reuse
Post by: Swoopert on 03/06/2018 08:15 am
No success so far.
Far from success.
Hundreds of yards.
So nothing borne out.
Something in the current approach seems to may be a major issue.

Whilst I acknowledge that the desired outcome has not yet been fully achieved, and some fine-tuning will be done, returning a fairing intact within hundreds of yards of its target is indubitably a success for the methodology, bearing in mind the fairing's starting position, shape, density and velocity.

Anyway, whatever issues there may be, I don't believe there is any evidence to suggest that parasitic drag is a major one, and that SpaceX would have to change their approach.
Title: Re: Fairing reuse
Post by: mme on 03/06/2018 08:22 am
I don't believe that this will have been a major issue, which is borne out by the success so far.

No success so far.
Far from success.
Hundreds of yards.
So nothing borne out.
Something in the current approach seems to may be a major issue.
Want to make a bet?
Title: Re: Fairing reuse
Post by: JamesH65 on 03/06/2018 09:28 am
I don't believe that this will have been a major issue, which is borne out by the success so far.

No success so far.
Far from success.
Hundreds of yards.
So nothing borne out.
Something in the current approach seems to may be a major issue.

Not enough evidence one way or another to make that claim. You are making stuff up to suit your agenda.
Title: Re: Fairing reuse
Post by: LouScheffer on 03/06/2018 12:31 pm
I don't believe that this will have been a major issue, which is borne out by the success so far.

No success so far.
Far from success.
Hundreds of yards.
So nothing borne out.
Something in the current approach seems to may be a major issue.
I'm much more optimistic.  The video linked above shows a human parachutist landing on a moving truck, much smaller then Mr. Stevens.   Scaling everything up by a factor of 10 gives the fairing recovery case.  (Fairing is about 20 times heavier, parachute will be correspondingly larger, and net is about this much larger.)

Also, there is the possibility, unlike the truck/human, to treat the landing as one big control problem.   A single computer could drive both the parachute steering lines and the ship throttle and steering.  I don't think this will be needed (the ship can probably just hold straight and steady) but it's a few extra degrees of freedom if the problem proves more difficult than expected.
Title: Re: Fairing reuse
Post by: speedevil on 03/06/2018 12:32 pm
Also, there is the possibility, unlike the truck/human, to treat the landing as one big control problem.   A single computer could drive both the parachute steering lines and the ship throttle and steering.  I don't think this will be needed (the ship can probably just hold straight and steady) but it's a few extra degrees of freedom if the problem proves more difficult than expected.

Reduce the problem to already-solved ones.
Co-manifested extreme skydiving.
Title: Re: Fairing reuse
Post by: acsawdey on 03/06/2018 03:42 pm
Also, there is the possibility, unlike the truck/human, to treat the landing as one big control problem.   A single computer could drive both the parachute steering lines and the ship throttle and steering.  I don't think this will be needed (the ship can probably just hold straight and steady) but it's a few extra degrees of freedom if the problem proves more difficult than expected.

Reduce the problem to already-solved ones.
Co-manifested extreme skydiving.

https://youtu.be/2-0M-q8tIHU (https://youtu.be/2-0M-q8tIHU)
Title: Re: Fairing reuse
Post by: john smith 19 on 03/06/2018 04:18 pm

Reduce the problem to already-solved ones.
Co-manifested extreme skydiving.

https://www.youtube.com/watch?v=2-0M-q8tIHU (https://www.youtube.com/watch?v=2-0M-q8tIHU)
[/quote]
The thing he's looking for was looked at in the early 1960's.  It was called MOOS. Man Out of Orbit Soonest.

It was never implemented partly due to budget limitations and the inability to find a test pilot with the necessary balls? Death wish? skills to test it.

OTOH test pilots participating in the "Man High" programme did bail out of high altitude balloons and break the sound barrier in free fall before (eventually) opening their parachute.

I can never see such concepts and not  picture Vin Diesel saying "I live for this ****"  :)
Coming in from about M6 or M5 (although quite a lot of that is above the "sensible" atmosphere is easier than orbit, but it will definitely be quite trip.
Title: Re: Fairing reuse
Post by: speedevil on 03/06/2018 04:37 pm
The thing he's looking for was looked at in the early 1960's.  It was called MOOS. Man Out of Orbit Soonest.

It was never implemented partly due to budget limitations and the inability to find a test pilot with the necessary balls? Death wish? skills to test it.

OTOH test pilots participating in the "Man High" programme did bail out of high altitude balloons and break the sound barrier in free fall before (eventually) opening their parachute.

I can never see such concepts and not  picture Vin Diesel saying "I live for this ****"  :)
Coming in from about M6 or M5 (although quite a lot of that is above the "sensible" atmosphere is easier than orbit, but it will definitely be quite trip.

MOOSE is very significantly higher energy.
(https://upload.wikimedia.org/wikipedia/en/thumb/4/49/Operation_MOOSE_%28figure_110%29.PNG/800px-Operation_MOOSE_%28figure_110%29.PNG)

Broadly similar areal density to the fairing though, which shows what might be possible.

https://en.wikipedia.org/wiki/MOOSE
Title: Re: Fairing reuse
Post by: john smith 19 on 03/06/2018 09:20 pm
MOOSE is very significantly higher energy.
(https://upload.wikimedia.org/wikipedia/en/thumb/4/49/Operation_MOOSE_%28figure_110%29.PNG/800px-Operation_MOOSE_%28figure_110%29.PNG)

Broadly similar areal density to the fairing though, which shows what might be possible.

https://en.wikipedia.org/wiki/MOOSE
Hmmm.

I do like the smooth way the foam in place process results in a nice neat cone properly aligned for entry.   :)

And IRL?

There's "Take a calculated risk" (pretty much the job description for a test pilot) and then there's Russian Roulette with 3 chambers loaded.  :(
Title: Re: Fairing reuse
Post by: sevenperforce on 03/06/2018 09:55 pm
Sheets of paper can survive re-entry unscathed. How bad is a human's drag coefficient? Is there any way to make a human's drag coefficient high enough to make it through re-entry without a shield?
Title: Re: Fairing reuse
Post by: speedevil on 03/06/2018 10:34 pm
I do like the smooth way the foam in place process results in a nice neat cone properly aligned for entry.   :)

And IRL?

There's "Take a calculated risk" (pretty much the job description for a test pilot) and then there's Russian Roulette with 3 chambers loaded.  :(

IRL, there are lots of things that have not been tried, because everyone looks at them and thinks they're too hard or silly.

Like fairing recovery.
(the foam was inside a bag, which inflated to a particular shape, the capsule was passively stable in the reentry direction due to being heavy on one side due to the astronaut.)

Title: Re: Fairing reuse
Post by: Craig_VG on 03/12/2018 08:13 pm
Shotwell: after demonstrating reusable boosters, it’s now “soul-crushing” to even dispose of payload fairings now. #SatShow

https://twitter.com/jeff_foust/status/973305568927649793
Title: Re: Fairing reuse
Post by: Zed_Noir on 03/13/2018 07:38 am
Shotwell: after demonstrating reusable boosters, it’s now “soul-crushing” to even dispose of payload fairings now. #SatShow

https://twitter.com/jeff_foust/status/973305568927649793

It got nothing to do with soul crushing. It is knowing the "pallets of cash" doing ocean impacts at about $6M a pop that any company management will found distressing. Especially if that $6M is 10% of your launch price.
Title: Re: Fairing reuse
Post by: wannamoonbase on 03/13/2018 10:38 am
Shotwell: after demonstrating reusable boosters, it’s now “soul-crushing” to even dispose of payload fairings now. #SatShow

https://twitter.com/jeff_foust/status/973305568927649793

It got nothing to do with soul crushing. It is knowing the "pallets of cash" doing ocean impacts at about $6M a pop that any company management will found distressing. Especially if that $6M is 10% of your launch price.


I wonder what ULA’s cost per fairing is and what percentage of launch cost.  1-2%
Title: Re: Fairing reuse
Post by: niwax on 03/13/2018 10:52 am
Shotwell: after demonstrating reusable boosters, it’s now “soul-crushing” to even dispose of payload fairings now. #SatShow

https://twitter.com/jeff_foust/status/973305568927649793

It got nothing to do with soul crushing. It is knowing the "pallets of cash" doing ocean impacts at about $6M a pop that any company management will found distressing. Especially if that $6M is 10% of your launch price.


I wonder what ULA’s cost per fairing is and what percentage of launch cost.  1-2%

You see, if your rocket is $500M, fairings are only 1% of your price...
Title: Re: Fairing reuse
Post by: docmordrid on 03/14/2018 01:50 pm
And if you're flying an automated, reusable, satellite deployer/Chomper with a cargo door(s) it's 0% - which eliminates the problem completely.
Title: Re: Fairing reuse
Post by: wannamoonbase on 03/30/2018 04:30 pm
Bump, anyone, anyone with info on today's fairing recovery attempt.
Title: Re: Fairing reuse
Post by: nacnud on 03/30/2018 04:35 pm
I presume you've seen this.
Title: Re: Fairing reuse
Post by: cscott on 03/30/2018 04:38 pm
That Elon quote makes it seem like Mr Steven is actively chasing the fairing. Maybe the theory that the fairing gives a predicted target update after initial dispersions is correct, and Mr Steven has to book it to get there in time. (IIRC the discussion was about why Mr Steven was such a fast boat, and whether variant techniques with faster-but-smaller boats (like picking up a trailing tow line and giving the fairing a ride) would be feasible.)
Title: Re: Fairing reuse
Post by: ZachS09 on 03/30/2018 04:42 pm
My best possible theory as to why there's no immediate update about the fairing recovery is because it takes a really long time for the fairing to glide towards Mr. Steven.
Title: Re: Fairing reuse
Post by: RocketLover0119 on 03/30/2018 04:55 pm
Maybe the new parafoil worked so good it came down sooooooooooooo slow, giving Mr. steven a challenge.

My best possible theory as to why there's no immediate update about the fairing recovery is because it takes a really long time for the fairing to glide towards Mr. Steven.
Title: Re: Fairing reuse
Post by: tvg98 on 03/30/2018 04:58 pm
Quote
Elon Musk
‏@elonmusk
GPS guided parafoil twisted, so fairing impacted water at high speed. Air wake from fairing messing w parafoil steering. Doing helo drop tests in next few weeks to solve.

https://twitter.com/elonmusk/status/979764513233715200 (https://twitter.com/elonmusk/status/979764513233715200)
Title: Re: Fairing reuse
Post by: OxCartMark on 03/30/2018 05:15 pm
Whynot wouldn't they make a few fiberglass dummy fairing halves and drop them by helicopter onto Mr. Steven?  Seems to me that if you had a pallet load of money falling from the sky you'd want a well practiced catcher.  You can pay thousands per day to sit in port or you can pay a bit more to work out the details of catching fairings.  Unless they've not been able to get the fairings down to a predictable location and under parachute under control.

Quote
Elon Musk
Doing helo drop tests in next few weeks to solve.

Hopefully they can do the testing with a fairing shaped object and not just a small area equivalent mass.  I speculate but not with certainty that they'll come to the conclusion that this method with this hardware isn't a good approach, for reasons I stated upthread.  Not saying its necessarily so but my speculation has quite a bit of lean to it.
Title: Re: Fairing reuse
Post by: Swoopert on 03/30/2018 07:02 pm
Well, that's shocked me...Good call OxCartMark...Looks like I was completely wrong. I'm flabbergasted that SpaceX have been caught out by parasitic drag!
Title: Re: Fairing reuse
Post by: fthomassy on 03/30/2018 07:20 pm
Hopefully they can do the testing with a fairing shaped object and not just a small area equivalent mass.
Where would they get a mass + shape simulator I wonder?
(https://cdn.teslarati.com/wp-content/uploads/2018/02/Mr-Steven-and-fairing-detail-2-Pauline-Acalin.jpg)
Title: Re: Fairing reuse
Post by: speedevil on 03/30/2018 07:21 pm
Where would they get a mass + shape simulator I wonder?

Commercial crew tests of a parachute out of a C130 are happening soon.
I wonder if just throwing the fairing out too would be practical.
Title: Re: Fairing reuse
Post by: IanThePineapple on 03/30/2018 07:27 pm
Hopefully they can do the testing with a fairing shaped object and not just a small area equivalent mass.
Where would they get a mass + shape simulator I wonder?

Using that as an engineering and drop test article would be perfect, it's already paid for and has been used, and likely isn't in a condition where they would want to use it again for commercial flights. Similar to what was done with Grasshopper. It was used as a qualification test article, and there was no other need for it after that. So why not use it for something else?
Title: Re: Fairing reuse
Post by: DistantTemple on 03/30/2018 07:30 pm
Here's a perhaps relevant video I previously posted on the PAZ thread, of a parachutist landing on a moving truck.  He guides himself to roughly the right spot, going in circles to do so, then he and the truck both line up on final.   The truck then drives straight and a little slower than the forward speed of the parachute.  He hits a spot which is maybe 2 meters wide by 5 meters long.
Parachutist landing on moving truck (https://www.youtube.com/watch?v=1OzoB5kwQ3Q)
Great Video.... down the line a really MAD parachute jump... stow away in a Falcon Faring! Ride it through re-entry. And if you hit the boat, you get a bonus! Pressure suit may interfere with the experience. Unfortunately some minor issues with human rating, and safety my interfere. 
Title: Re: Fairing reuse
Post by: photonic on 03/30/2018 08:07 pm
Commercial crew tests of a parachute out of a C130 are happening soon.
I wonder if just throwing the fairing out too would be practical.

A C130 is not large enough, unfortunately. The width of is cargo hold is ~3 meters, while the fairing is 5 meters. You probably need the largest Antonov.
Title: Re: Fairing reuse
Post by: docmordrid on 03/30/2018 08:40 pm
>
A C130 is not large enough, unfortunately. ....You probably need the largest Antonov.

Uhhh....no.

Elon Musk @elonmusk
GPS guided parafoil twisted, so fairing impacted water at high speed. Air wake from fairing messing w parafoil steering. Doing helo drop tests in next few weeks to solve.
Title: Re: Fairing reuse
Post by: Burninate on 03/30/2018 09:48 pm
>
A C130 is not large enough, unfortunately. ....You probably need the largest Antonov.

Uhhh....no.

Elon Musk @elonmusk
GPS guided parafoil twisted, so fairing impacted water at high speed. Air wake from fairing messing w parafoil steering. Doing helo drop tests in next few weeks to solve.

A C130 can't really carry a large, light slung load, aerodynamically.  A helicopter can.
Title: Re: Fairing reuse
Post by: photonic on 03/30/2018 09:50 pm
>
A C130 is not large enough, unfortunately. ....You probably need the largest Antonov.

Uhhh....no.

Elon Musk @elonmusk
GPS guided parafoil twisted, so fairing impacted water at high speed. Air wake from fairing messing w parafoil steering. Doing helo drop tests in next few weeks to solve.

I know what a helo drop is and that Elon wants to do one. I was just answering to the suggestion to drop a fairing out of the cargo hold of a transport airplane. A C130 is way to small for that, but an Antonov 225 has a hold of 6m wide by 4m height by 45 m in length, which I guess should just fit: http://www.buran-energia.com/mriya-antonov/mriya-carac.php

These planes are probably expensive to hire for a day, so I agree that using a helicopter is the way to go.
Title: Re: Fairing reuse
Post by: gongora on 03/30/2018 10:09 pm
Commercial crew tests of a parachute out of a C130 are happening soon.
I wonder if just throwing the fairing out too would be practical.

A C130 is not large enough, unfortunately. The width of is cargo hold is ~3 meters, while the fairing is 5 meters. You probably need the largest Antonov.

The next-to-largest Antonov seems to work just fine.
Title: Re: Fairing reuse
Post by: deruch on 03/30/2018 11:13 pm
>
A C130 is not large enough, unfortunately. ....You probably need the largest Antonov.

Uhhh....no.

Elon Musk @elonmusk
GPS guided parafoil twisted, so fairing impacted water at high speed. Air wake from fairing messing w parafoil steering. Doing helo drop tests in next few weeks to solve.

I know what a helo drop is and that Elon wants to do one. I was just answering to the suggestion to drop a fairing out of the cargo hold of a transport airplane. A C130 is way to small for that, but an Antonov 225 has a hold of 6m wide by 4m height by 45 m in length, which I guess should just fit: http://www.buran-energia.com/mriya-antonov/mriya-carac.php

These planes are probably expensive to hire for a day, so I agree that using a helicopter is the way to go.

Not to mention that the cargo door is opened by hinging up the nose of the plane, which would make an airborne drop difficult.
Title: Re: Fairing reuse
Post by: Bob Shaw on 03/31/2018 12:07 am

Not to mention that the cargo door is opened by hinging up the nose of the plane, which would make an airborne drop difficult.

Actually, there's an equally large door at the rear on both big Antonovs, plus a whole series of winches. I crawled all over one a few years back at Prestwick Airport in Scotland while photographing it while it was delivering a helicopter for Bristow.
Title: Re: Fairing reuse
Post by: OxCartMark on 03/31/2018 01:11 pm

Not to mention that the cargo door is opened by hinging up the nose of the plane, which would make an airborne drop difficult.

Actually, there's an equally large door at the rear on both big Antonovs, plus a whole series of winches. I crawled all over one a few years back at Prestwick Airport in Scotland while photographing it while it was delivering a helicopter for Bristow.

I call "nope" on the AN-225 having a back door.  AN-124 has one but not AN-225.
Title: Re: Fairing reuse
Post by: alang on 03/31/2018 02:15 pm
Whynot wouldn't they make a few fiberglass dummy fairing halves and drop them by helicopter onto Mr. Steven?  Seems to me that if you had a pallet load of money falling from the sky you'd want a well practiced catcher.  You can pay thousands per day to sit in port or you can pay a bit more to work out the details of catching fairings.  Unless they've not been able to get the fairings down to a predictable location and under parachute under control.

Quote
Elon Musk
Doing helo drop tests in next few weeks to solve.

Hopefully they can do the testing with a fairing shaped object and not just a small area equivalent mass.  I speculate but not with certainty that they'll come to the conclusion that this method with this hardware isn't a good approach, for reasons I stated upthread.  Not saying its necessarily so but my speculation has quite a bit of lean to it.

Are you effectively saying that the fairing is such a distributed mass that it acts like a parachute itself?
Does anyone know if the parafoil has a drogue chute as well? I wonder how complex this system is.
Title: Re: Fairing reuse
Post by: Inoeth on 03/31/2018 03:35 pm
I just hope there's a blooper video of the fairing crashing into the sea once they get this right.. including the helo tests that now might happen in the near future...

I also agree about them using the fairing from the previous Iridium mission that clearly won't fly again but certainly could be used for this kind of project...

Anyways, since Elon specifically said Helicopters, not planes, which kind of chopper would they rent out for this kind of job and how much would it cost them?
Title: Re: Fairing reuse
Post by: deruch on 04/01/2018 01:54 am
Other fairings potentially available for test drop usage are those that had issues before some of the recent flights (Zuma and ?, don't recall).  Not sure if they were just tested and cleared/repaired or if they were swapped out to minimize launch delay. 
Title: Re: Fairing reuse
Post by: ZachS09 on 04/01/2018 03:49 am
Cross-posting from the Iridium-NEXT F5 Update Thread:

https://www.teslarati.com/spacex-recovers-fairing-half-mr-steven-clawboat-iridium-launch/

Mr. Steven apparently brought back another fairing half, which means that both the Iridium-NEXT F5 fairing and the Paz fairing could be reused on a future mission if SpaceX wants to start reflying fairings ASAP.
Title: Re: Fairing reuse
Post by: cppetrie on 04/01/2018 04:54 am
By all indications so far PAZ is fairing 2.0 and Iridium 5 is 1.0 so not a pair. Also, they’ve both gone in the drink so I think it’s very unlikely these reflux on a mission. That said, these are both great candidates for the helicopter drop tests Elon mentioned.
Title: Re: Fairing reuse
Post by: sanman on 04/01/2018 09:10 am
Cross-posting from the Iridium-NEXT F5 Update Thread:

https://www.teslarati.com/spacex-recovers-fairing-half-mr-steven-clawboat-iridium-launch/

Mr. Steven apparently brought back another fairing half, which means that both the Iridium-NEXT F5 fairing and the Paz fairing could be reused on a future mission if SpaceX wants to start reflying fairings ASAP.

For a given launch, are both fairing halves identical, or is there some male-female complementarity?
Title: Re: Fairing reuse
Post by: fthomassy on 04/01/2018 02:50 pm
For a given launch, are both fairing halves identical, or is there some male-female complementarity?
They are different. See discussions of Paz photos where parts of both were observed.
Title: Re: Fairing reuse
Post by: Archibald on 04/01/2018 03:38 pm

Not to mention that the cargo door is opened by hinging up the nose of the plane, which would make an airborne drop difficult.

Actually, there's an equally large door at the rear on both big Antonovs, plus a whole series of winches. I crawled all over one a few years back at Prestwick Airport in Scotland while photographing it while it was delivering a helicopter for Bristow.

I call "nope" on the AN-225 having a back door.  AN-124 has one but not AN-225.

And I second that. The An-225 has a very different rear fuselage with a big H-tail (B-24 style albeit far more modern) for clearance of MAKS and Buran - and in the process, they deleted the rear cargo door.
Title: Re: Fairing reuse
Post by: niwax on 04/01/2018 05:02 pm

Not to mention that the cargo door is opened by hinging up the nose of the plane, which would make an airborne drop difficult.

Actually, there's an equally large door at the rear on both big Antonovs, plus a whole series of winches. I crawled all over one a few years back at Prestwick Airport in Scotland while photographing it while it was delivering a helicopter for Bristow.

I call "nope" on the AN-225 having a back door.  AN-124 has one but not AN-225.

And I second that. The An-225 has a very different rear fuselage with a big H-tail (B-24 style albeit far more modern) for clearance of MAKS and Buran - and in the process, they deleted the rear cargo door.

Renting an An-225 for a week to do a bunch of drop tests seems a bit overkill anyways
Title: Re: Fairing reuse
Post by: OnWithTheShow on 04/03/2018 03:32 pm
By all indications so far PAZ is fairing 2.0 and Iridium 5 is 1.0 so not a pair. Also, they’ve both gone in the drink so I think it’s very unlikely these reflux on a mission. That said, these are both great candidates for the helicopter drop tests Elon mentioned.

Carbon fiber itself it not susceptible to degradation from sea water and from what I understand is the most expensive part of the fairing. Seems easy to swap out the innards and reuse the fiber shell.
Title: Re: Fairing reuse
Post by: cppetrie on 04/03/2018 03:52 pm
By all indications so far PAZ is fairing 2.0 and Iridium 5 is 1.0 so not a pair. Also, they’ve both gone in the drink so I think it’s very unlikely these reflux on a mission. That said, these are both great candidates for the helicopter drop tests Elon mentioned.

Carbon fiber itself it not susceptible to degradation from sea water and from what I understand is the most expensive part of the fairing. Seems easy to swap out the innards and reuse the fiber shell.
I don’t disagree, but if it were that simple why are they going to such great lengths to try and catch them. They seem to have figured out how to drop them softly in the water and be nearby with a ship to recover them quickly. That they seem very intent on keeping them completely out of the water suggests that getting them wet is a problem.
Title: Re: Fairing reuse
Post by: speedevil on 04/03/2018 04:01 pm
I don’t disagree, but if it were that simple why are they going to such great lengths to try and catch them. They seem to have figured out how to drop them softly in the water and be nearby with a ship to recover them quickly. That they seem very intent on keeping them completely out of the water suggests that getting them wet is a problem.

They have worked out how to drop them visibly intact into water.
Are they structurally sound and will customers believe that is another question.

How often is this likely to happen is another.

Internal delamination or compromise of the core due to shear with the large forces imposed as the structure bends on impact with the ocean is possible.
Title: Re: Fairing reuse
Post by: cppetrie on 04/03/2018 04:04 pm
I don’t disagree, but if it were that simple why are they going to such great lengths to try and catch them. They seem to have figured out how to drop them softly in the water and be nearby with a ship to recover them quickly. That they seem very intent on keeping them completely out of the water suggests that getting them wet is a problem.

They have worked out how to drop them visibly intact into water.
Are they structurally sound and will customers believe that is another question.

How often is this likely to happen is another.

Internal delamination or compromise of the core due to shear with the large forces imposed as the structure bends on impact with the ocean is possible.
All true which is why in addition to them being 1.0 and 2.0 halves I suggested upthread these wouldn’t refly again.
Title: Re: Fairing reuse
Post by: woods170 on 04/03/2018 05:55 pm
By all indications so far PAZ is fairing 2.0 and Iridium 5 is 1.0 so not a pair. Also, they’ve both gone in the drink so I think it’s very unlikely these reflux on a mission. That said, these are both great candidates for the helicopter drop tests Elon mentioned.

Carbon fiber itself it not susceptible to degradation from sea water and from what I understand is the most expensive part of the fairing. Seems easy to swap out the innards and reuse the fiber shell.

Seawater gets into the honeycomb inner structure and affects just about every metallic part of the fairing. Some of those metallic parts are integrated into the fiber shell and cannot be replaced without tearing up the fiber shell.

Therefore, the minute a fairing half hits the ocean surface it becomes a total loss.
Title: Re: Fairing reuse
Post by: Jim on 04/03/2018 06:06 pm

Carbon fiber itself it not susceptible to degradation from sea water and from what I understand is the most expensive part of the fairing. Seems easy to swap out the innards and reuse the fiber shell.

Not really.  The composite is not completely sealed.  Water intrusion would be an issue.
Title: Re: Fairing reuse
Post by: JamesH65 on 04/04/2018 01:01 pm
By all indications so far PAZ is fairing 2.0 and Iridium 5 is 1.0 so not a pair. Also, they’ve both gone in the drink so I think it’s very unlikely these reflux on a mission. That said, these are both great candidates for the helicopter drop tests Elon mentioned.

Carbon fiber itself it not susceptible to degradation from sea water and from what I understand is the most expensive part of the fairing. Seems easy to swap out the innards and reuse the fiber shell.
I don’t disagree, but if it were that simple why are they going to such great lengths to try and catch them. They seem to have figured out how to drop them softly in the water and be nearby with a ship to recover them quickly. That they seem very intent on keeping them completely out of the water suggests that getting them wet is a problem.

They could be landing in very rough water - which would probably trash them before they could be recovered from the water.

But my thoughts are the main issue is simply water ingression to the honeycomb.
Title: Re: Fairing reuse
Post by: Swedish chef on 04/06/2018 05:00 pm
Some information on page 77-78 of Draft Environmental Assessment for Issuing a Reentry License to SpaceX for Landing the Dragon Spacecraft in the Gulf of Mexico contains information to the parachute used in the fairing recovery that some of you might find interesting.
Title: Re: Fairing reuse
Post by: OxCartMark on 04/06/2018 06:10 pm
My first thought being not a lawyer and not familiar with such documents is that they are spreading meaningless information over the page to fill space and check the box while not really saying much of anything.  Intentionally.
Title: Re: Fairing reuse
Post by: photonic on 04/08/2018 09:41 pm
Elon posted a new picture from the landed Iridium-5 fairing on twitter:

Quote
Elon Musk (repyling to @Teslerati)
Oh yeah, forgot to mention it actually landed fine, just not on Mr Steven

https://twitter.com/elonmusk/status/980647734888681472

Looks like new, but at least some of the foam got wet.
Title: Re: Fairing reuse
Post by: wannamoonbase on 04/08/2018 11:41 pm
Elon posted a new picture from the landed Iridium-5 fairing on twitter:

Quote
Elon Musk (repyling to @Teslerati)
Oh yeah, forgot to mention it actually landed fine, just not on Mr Steven

https://twitter.com/elonmusk/status/980647734888681472

Looks like new, but you at least some of the foam got wet.

So close. They’ll figure this out soon, they’ve got a lot of creative and smart engineers.

$5 million per flight is big, but allowing for a higher flight rate may be even bigger. 
Title: Re: Fairing reuse
Post by: Swoopert on 04/12/2018 03:40 pm
Some information on page 77-78 of Draft Environmental Assessment for Issuing a Reentry License to SpaceX for Landing the Dragon Spacecraft in the Gulf of Mexico contains information to the parachute used in the fairing recovery that some of you might find interesting.

64/113 ft2 drogues with 1782/3000 ft2 canopies with 42-50ft line lengths! They are not messing around small canopies! The best guesstimate I can find for the mass of a fairing half is 875kg (several sites have the full fairing at 1750kg), which puts the wing-loading on those parafoils at a distinctly un-sporty 1.08 and 0.64 lbs/ft2 respectively, those things are going to be floaty with a very slow to negative ground-speed in off-shore wind conditions...and being so lightly loaded I would have thought are very susceptible to parasitic drag issues. Colour me surprised again...but my experience is all with sport parachutes...

For reference, the main canopy (loaded at 2.55) in my profile pic is the same size as their Type 2 Drogue (which is loaded at 17 lbs/ft2!).

Edit: to add wing-loadings
Title: Re: Fairing reuse
Post by: EnigmaSCADA on 04/12/2018 07:40 pm
Elon posted a new picture from the landed Iridium-5 fairing on twitter:

Quote
Elon Musk (repyling to @Teslerati)
Oh yeah, forgot to mention it actually landed fine, just not on Mr Steven

https://twitter.com/elonmusk/status/980647734888681472

Looks like new, but at least some of the foam got wet.
Looks like the hull of a boat just sitting there on the water. Just integrate an outboard motor and drive it home!
Title: Re: Fairing reuse
Post by: aero on 04/13/2018 01:43 am
Elon posted a new picture from the landed Iridium-5 fairing on twitter:

Quote
Elon Musk (repyling to @Teslerati)
Oh yeah, forgot to mention it actually landed fine, just not on Mr Steven

https://twitter.com/elonmusk/status/980647734888681472

Looks like new, but at least some of the foam got wet.
Looks like the hull of a boat just sitting there on the water. Just integrate an outboard motor and drive it home!

Just keep the parafoil from collapsing and sail it home!
Title: Re: Fairing reuse
Post by: deruch on 04/13/2018 02:32 am
At the nose of the fairing for the TESS mission you can see the nozzle/outlet for the ACS thrusters used to maintain stability during reentry.
Title: Re: Fairing reuse
Post by: cscott on 04/13/2018 10:03 am
Some information on page 77-78 of Draft Environmental Assessment for Issuing a Reentry License to SpaceX for Landing the Dragon Spacecraft in the Gulf of Mexico contains information to the parachute used in the fairing recovery that some of you might find interesting.

64/113 ft2 drogues with 1782/3000 ft2 canopies with 42-50ft line lengths! They are not messing around small canopies! The best guesstimate I can find for the mass of a fairing half is 875kg (several sites have the full fairing at 1750kg), which puts the wing-loading on those parafoils at a distinctly un-sporty 1.08 and 0.64 lbs/ft2 respectively, those things are going to be floaty with a very slow to negative ground-speed in off-shore wind conditions...and being so lightly loaded I would have thought are very susceptible to parasitic drag issues. Colour me surprised again...but my experience is all with sport parachutes...

For reference, the main canopy (loaded at 2.55) in my profile pic is the same size as their Type 2 Drogue (which is loaded at 17 lbs/ft2!).

Edit: to add wing-loadings
What influence would extreme altitude or extreme speed have, if any?  Perhaps the fact that the parachutes are not operating at steady state but in fact actively decelerating the load raises the wing loading to a more typical value, at least until terminal velocity is reached?  IIRC the stage 1 return doesn't reach terminal velocity until a quite low altitude.  Maybe there's a way to dump some of the excess chute area once they've reached terminal velocity---or perhaps trying to find the compromise between appropriate loading at initial entry and appropriate loading at sea level just before landing is what is making recovery so challenging.

Certainly recent recoveries are consistent with the idea that the chutes are successful in getting the fairing down to low altitude, but then they get so "floaty" that it's real hard to catch them on Mr Steven.
Title: Re: Fairing reuse
Post by: swervin on 04/19/2018 04:25 am
And word on fairing survival down to an ocean landing for the TESS mission?
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 04/21/2018 08:08 am
And word on fairing survival down to an ocean landing for the TESS mission?

Quote
That, my friends, appears to be a complete half fairing on board GO Pursuit. Quick grab off my preview screen. Some of the Falcon 9 has arrived at Port Canaveral #SpaceXFleet

https://twitter.com/julia_bergeron/status/987589035102298113
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 04/21/2018 08:45 am
A better shot:

Quote
GO Pursuit, with what appears to be a complete fairing half on deck, arrived into Port Canaveral approx. 3:15 am EDT this morning. In a few short hours we should be seeing OCISILY being led in by Hawk and GO Quest after cruise ships are safely docked. #SpaceXFleet @SpaceX

https://twitter.com/julia_bergeron/status/987610215884484613 (https://twitter.com/julia_bergeron/status/987610215884484613)
Title: Re: Fairing reuse
Post by: swervin on 04/21/2018 09:31 am
Great, thx for sharing. They’re getting better...

Does anyone have an informed opinion on the effects of salt water on these fairings? Landing them safely is a great beginning in proving the concept, but I would think the investment in the craft to catch them was required to avoid salt water... or may now be reconsidered if these are reusable without the ‘catchers mit’?

Splinter
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 04/21/2018 11:28 am
Great shot in daylight by @marekcyzio:

Quote
Looks like it #Tess #Falcon9 #SpaceX

https://twitter.com/marekcyzio/status/987652390143881217
Title: Re: Fairing reuse
Post by: speedevil on 04/21/2018 11:37 am
Great, thx for sharing. They’re getting better...

Does anyone have an informed opinion on the effects of salt water on these fairings?
Saltwater in principle can be managed. The structure is in principle waterproof,and suitable materials can be found for any accessories, or those replaced.
Hitting a very solid ocean, with a flexible structure, at an unpredictable orientation and speed, and perhaps having subsequent loading due to water inside moving in response to external wind and wave action, may impart very hard to model loads on the fairing, making it hard to reasonably assess if it's remained within its structural limits.

Or, it may be they know for certain that the impact is in the range where it could sustain damage.
If it may, then the question arises of how to develop and prove out a complete non-destructive test methodology, and possibly even repair.
This can be expensive.

Or maybe it was always going to be fine falling in the water, and the fairing recovery efforts were a smokescreen to cover S2 recovery practice.

To even start to answer the question, you'd need to know the exact construction, and load limits on the structure, and the actual impact speed in the water, and which way down it came.
Unfortunately problematic.

Title: Re: Fairing reuse
Post by: MarekCyzio on 04/21/2018 11:54 am
Slightly better view. Edit - sorry, still learning how to use new camera.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 04/21/2018 12:01 pm
I can’t quite work out from the shape of the tarpaulins if the fairing half is in pieces or if there’s more than one fairing half recovered?
Title: Re: Fairing reuse
Post by: Johnnyhinbos on 04/21/2018 12:06 pm
I can’t quite work out from the shape of the tarpaulins if the fairing half is in pieces or if there’s more than one fairing half recovered?
I was thinking the same thing. What’s the OTHER thing under the tarp...?

Edit to add - this GO ship doesn’t have an A-frame. So if she was in the recovery area unsupported then the fairing was probably winched in through the transom, which is probably not overly good for the fairing either.
Title: Re: Fairing reuse
Post by: DistantTemple on 04/21/2018 10:26 pm
I can’t quite work out from the shape of the tarpaulins if the fairing half is in pieces or if there’s more than one fairing half recovered?
I was thinking the same thing. What’s the OTHER thing under the tarp...?

Edit to add - this GO ship doesn’t have an A-frame. So if she was in the recovery area unsupported then the fairing was probably winched in through the transom, which is probably not overly good for the fairing either.
We saw the one in LA that seemed in great condition (from a photo!) with its guts being ripped out (all the blocks/panels on the inside), and this one is haphazardly tarped, and probably roughly handled in recovery. These can't be intended for re-use, as they would have to be stripped to the shell, and then comprehensively examined with ultrasound or whatever is used to hunt for stress damage.
However since they land and float they are a hazard to navigation, and must be collected or sunk. And collection is easier once Go-pursuit has got to the location. I expect a few will end up as exhibits, but reflight will only happen to those that are properly "caught". 
Title: Re: Fairing reuse
Post by: wannamoonbase on 04/22/2018 03:28 pm
Seems that they are trying to figure out para-foil deployment.  Actually recovering the fairing in a usable condition will come very quickly after they can predict and control the flight path. 

When we see them flying hardware on both halves we'll know they are getting close.

My 2 cents: I bet they are only a few more attempts (iterations) from success.

Edit: I'm dying to see video of the return flight, parafoil deployment and attempt to land in the net.  More Sci-Fi in real life.
Title: Re: Fairing reuse
Post by: speedevil on 04/22/2018 04:08 pm
When we see them flying hardware on both halves we'll know they are getting close.

My 2 cents: I bet they are only a few more attempts (iterations) from success.
I wonder if we'll end up with S2 and fairing recovery competing for boats.
Title: Re: Fairing reuse
Post by: Rebel44 on 04/22/2018 09:08 pm
When we see them flying hardware on both halves we'll know they are getting close.

My 2 cents: I bet they are only a few more attempts (iterations) from success.
I wonder if we'll end up with S2 and fairing recovery competing for boats.

Getting more boats is relatively easy/cheap (considering cost of fairing and value or recovered 2nd stage)
Title: Re: Fairing reuse
Post by: Barrie on 04/22/2018 09:19 pm
I can’t quite work out from the shape of the tarpaulins if the fairing half is in pieces or if there’s more than one fairing half recovered?
I was thinking the same thing. What’s the OTHER thing under the tarp...?

Edit to add - this GO ship doesn’t have an A-frame. So if she was in the recovery area unsupported then the fairing was probably winched in through the transom, which is probably not overly good for the fairing either.

Maybe they recovered both halves, but the one equipped for recovery is in better shape, as one would expect
Title: Re: Fairing reuse
Post by: speedevil on 04/23/2018 06:15 am
Getting more boats is relatively easy/cheap (considering cost of fairing and value or recovered 2nd stage)
I was wondering if S2 recovery attempts were started before fairing recovery had been nailed, and a second/third boat bought. Clearly this would not be a usual operation going forward.
Title: Re: Fairing reuse
Post by: john smith 19 on 04/23/2018 06:52 am
Getting more boats is relatively easy/cheap (considering cost of fairing and value or recovered 2nd stage)
I was wondering if S2 recovery attempts were started before fairing recovery had been nailed, and a second/third boat bought. Clearly this would not be a usual operation going forward.
SX have certainly wanted to do S2 for full reusability

Fariing reuse seems to be a quite late addition, when Musk realized how much a bag of cash they cost and how difficult S2 recovery is likely to be without a drastic cut in payload to begin with.
Title: Re: Fairing reuse
Post by: speedevil on 04/23/2018 07:38 am
Fariing reuse seems to be a quite late addition, when Musk realized how much a bag of cash they cost and how difficult S2 recovery is likely to be without a drastic cut in payload to begin with.

If you can do LOX transfer, payload to GTO goes up a lot.

Assuming recovery hardware is 2 tons, and stage weight is 4 tons.

Normal RTLS gets you 3.5 tons to GTO.
2* RTLS, with 10 tons of oxygen transferred gets you to a little over expendable performance.

2*ASDS beats FH recovery*3.

And, of course, 7 tonsish to LEO, with RTLS, if you're recovering S2 looks damn good for Starlink.
Title: Re: Fairing reuse
Post by: JamesH65 on 04/23/2018 12:18 pm
Fariing reuse seems to be a quite late addition, when Musk realized how much a bag of cash they cost and how difficult S2 recovery is likely to be without a drastic cut in payload to begin with.

If you can do LOX transfer, payload to GTO goes up a lot.

Assuming recovery hardware is 2 tons, and stage weight is 4 tons.

Normal RTLS gets you 3.5 tons to GTO.
2* RTLS, with 10 tons of oxygen transferred gets you to a little over expendable performance.

2*ASDS beats FH recovery*3.

And, of course, 7 tonsish to LEO, with RTLS, if you're recovering S2 looks damn good for Starlink.

Transfer from what, and where?
Title: Re: Fairing reuse
Post by: speedevil on 04/23/2018 12:23 pm
Fariing reuse seems to be a quite late addition, when Musk realized how much a bag of cash they cost and how difficult S2 recovery is likely to be without a drastic cut in payload to begin with.

If you can do LOX transfer, payload to GTO goes up a lot.

Assuming recovery hardware is 2 tons, and stage weight is 4 tons.

Normal RTLS gets you 3.5 tons to GTO.
2* RTLS, with 10 tons of oxygen transferred gets you to a little over expendable performance.

2*ASDS beats FH recovery*3.

And, of course, 7 tonsish to LEO, with RTLS, if you're recovering S2 looks damn good for Starlink.

Transfer from what, and where?

Transfer from a F9 launched with no payload other than oxygen over to another F9 launched with a little less than nominal oxygen.
Title: Re: Fairing reuse
Post by: Robotbeat on 04/23/2018 12:55 pm
The hit to LEO payload needn’t be very high. Only GTO and other high energy orbits have a big payload hit. With ballute recovery, fully reusable F9 payload to LEO should be greater than the initial expendable Falcon 9 v1.0.
Title: Re: Fairing reuse
Post by: Prettz on 04/23/2018 02:44 pm
Transfer from a F9 launched with no payload other than oxygen over to another F9 launched with a little less than nominal oxygen.
How does this lower launch costs?
Title: Re: Fairing reuse
Post by: speedevil on 04/23/2018 02:44 pm
Transfer from a F9 launched with no payload other than oxygen over to another F9 launched with a little less than nominal oxygen.
How does this lower launch costs?
Everything is reused.
Title: Re: Fairing reuse
Post by: envy887 on 04/23/2018 02:45 pm
Transfer from a F9 launched with no payload other than oxygen over to another F9 launched with a little less than nominal oxygen.
How does this lower launch costs?

Both upper stages can be fully reused, which saves the ~$10 million of expending a single upper stage.
Title: Re: Fairing reuse
Post by: Comga on 04/23/2018 03:12 pm
Transfer from a F9 launched with no payload other than oxygen over to another F9 launched with a little less than nominal oxygen.
How does this lower launch costs?

Both upper stages can be fully reused, which saves the ~$10 million of expending a single upper stage.

And this discussion belongs in the "Fairing Reuse" thread instead of one of the second stage or general Falcon threads because....?
Title: Re: Fairing reuse
Post by: Prettz on 04/23/2018 03:33 pm
Transfer from a F9 launched with no payload other than oxygen over to another F9 launched with a little less than nominal oxygen.
How does this lower launch costs?

Both upper stages can be fully reused, which saves the ~$10 million of expending a single upper stage.
I didn't realize you were talking about recovering both of them. I'd still wonder if that would actually save costs over a single launch once everything is taken into account.
Title: Re: Fairing reuse
Post by: Chris Bergin on 04/23/2018 05:41 pm
OK, I see how this went off track, but let's get back on track.

"But Chris, I want to quote and respond to the posts above!!"

"No! Don't make me put my foot down!" ;D
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 04/23/2018 09:44 pm
Quote
Mr Steven what are you even doing?
#spacex #mrsteven

https://twitter.com/w00ki33/status/988531119015407616
Title: Re: Fairing reuse
Post by: whitelancer64 on 04/23/2018 10:09 pm
Quote
Mr Steven what are you even doing?
#spacex #mrsteven

https://twitter.com/w00ki33/status/988531119015407616

Ooohh, looks like speed trials.

Hit the gas to scoot to where the fairing will be.
Title: Re: Fairing reuse
Post by: wannamoonbase on 04/24/2018 01:44 am
Quote
Mr Steven what are you even doing?
#spacex #mrsteven

https://twitter.com/w00ki33/status/988531119015407616

Ooohh, looks like speed trials.

Hit the gas to scoot to where the fairing will be.

Maybe simulations or preps for the helicopter dropped tests that EM mentioned a few weeks ago.
Title: Re: Fairing reuse
Post by: john smith 19 on 04/24/2018 06:55 am
The hit to LEO payload needn’t be very high. Only GTO and other high energy orbits have a big payload hit. With ballute recovery, fully reusable F9 payload to LEO should be greater than the initial expendable Falcon 9 v1.0.
Glad to hear. Get flying!
Title: Re: Fairing reuse
Post by: Kabloona on 04/24/2018 01:22 pm
Quote
Mr Steven what are you even doing?
#spacex #mrsteven


Most likely explanation, from our own Johnnyhinbos:

Quote
John Hanzl (author)
@JohnHanzl
Replying to @w00ki33 @Teslarati and @SpaceX
Looks like a Coast Guard inspection (not a surprise inspection but a scheduled one). Testing firefighting systems, man overboard protocols, etc. Been aboard for one of those...
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 04/24/2018 07:35 pm
https://youtu.be/8rSJmZ4GOZA (https://youtu.be/8rSJmZ4GOZA)
Title: Re: Fairing reuse
Post by: swervin on 04/25/2018 02:16 am
Has it been confirmed that both fairing halves were recovers intact? It appears they’re both on the boat...
Title: Re: Fairing reuse
Post by: matthewkantar on 04/26/2018 02:15 am
Has it been confirmed that both fairing halves were recovers intact? It appears they’re both on the boat...

This video shows it.

https://www.youtube.com/watch?v=o-KgAhtXcMI
Title: Re: Fairing reuse
Post by: JamesH65 on 04/26/2018 11:32 am
That'll buff out.
Title: Re: Fairing reuse
Post by: IainMcClatchie on 04/26/2018 11:48 pm
It looks like the sound insulation is applied in the form of individual panels which have some kind of bright reflective edging.  Does anyone know why that would be?  The more obvious way to do it would be to spray foam on the inside, as was done on the outside of the Space Shuttle external tank.

I'm impressed that there appears to be almost no charring.  They're down to the last 50 m/s.  Pretty nice.
Title: Re: Fairing reuse
Post by: nacnud on 04/27/2018 12:48 am
The foam on the outside of the ET is thermal insulation rather than sound insulation. I don't know about the fairing insulation but I guess it is much lighter than ET foam and can only be made in sheets that need to be cut up to fit on the fairing inner surface.

Edit: This is what they use on Ariane 5 https://www.plasticsportal.net/wa/plasticsEU~ro_RO/portal/show/common/plasticsportal_news/2006/06_494?doc_lang=en_GB
Title: Re: Fairing reuse
Post by: wannamoonbase on 04/27/2018 01:31 am
It looks like the sound insulation is applied in the form of individual panels which have some kind of bright reflective edging.  Does anyone know why that would be?  The more obvious way to do it would be to spray foam on the inside, as was done on the outside of the Space Shuttle external tank.

I'm impressed that there appears to be almost no charring.  They're down to the last 50 m/s.  Pretty nice.

Then edging and face maybe to hold the material together.  The very light and whispy insulation is certainly for absorbing sound and vibration.  I was on a project once where we had to do a ton of acoustic testing. A lot of it feels like pure magic, but there is science behind matching material to the types of frequencies you want to absorb. Surface area for high frequencies.  Mass for low bass frequencies. 
Title: Re: Fairing reuse
Post by: Lar on 04/27/2018 03:50 pm
Off topic (after Chris asked to stop) aetherized
Title: Re: Fairing reuse
Post by: docmordrid on 05/02/2018 06:07 am
https://www.instagram.com/p/BiQ5qXnA_OM/

Title: Re: Fairing reuse
Post by: Lars-J on 05/02/2018 06:09 am
New instagram post from Elon Musk:

https://www.instagram.com/p/BiQ5qXnA_OM/?taken-by=elonmusk
Title: Re: Fairing reuse
Post by: mattstep on 05/02/2018 11:58 am
New instagram post from Elon Musk:

https://www.instagram.com/p/BiQ5qXnA_OM/?taken-by=elonmusk

Is it traveling wrong-end-first? I had pictured the top of the fairing headed into the wind.
Title: Re: Fairing reuse
Post by: Alastor on 05/02/2018 12:04 pm
New instagram post from Elon Musk:

https://www.instagram.com/p/BiQ5qXnA_OM/?taken-by=elonmusk

Is it traveling wrong-end-first? I had pictured the top of the fairing headed into the wind.

You can't necessarily choose.
Or it may be intentional, acting as a low aerodynamic surface to brake. This way it's probably easier to catch it while having a pretty well controlled descent.

It can even be a little bit of both : It sometimes flips if you plan for it not flipping, so it's better to try to have it always flip that way it's more reliable.
I can easily imagine the fairing taking a low aerodynamic position being one of the reasons for the early failures, where the parafoil would suddenly not be enough any more to keep the fairing in the air. 
Title: Re: Fairing reuse
Post by: Jim on 05/02/2018 01:58 pm
It looks like the sound insulation is applied in the form of individual panels which have some kind of bright reflective edging.  Does anyone know why that would be?  The more obvious way to do it would be to spray foam on the inside, as was done on the outside of the Space Shuttle external tank.

Yeah, that would make a nice and clean environment for spacecraft
Title: Re: Fairing reuse
Post by: JamesH65 on 05/02/2018 02:04 pm
New instagram post from Elon Musk:

https://www.instagram.com/p/BiQ5qXnA_OM/?taken-by=elonmusk

Is it traveling wrong-end-first? I had pictured the top of the fairing headed into the wind.

You could look at that image either as moving left to right or right to left. Depends on the angle from the camera.
Title: Re: Fairing reuse
Post by: Lars-J on 05/02/2018 04:08 pm
New instagram post from Elon Musk:

https://www.instagram.com/p/BiQ5qXnA_OM/?taken-by=elonmusk

Is it traveling wrong-end-first? I had pictured the top of the fairing headed into the wind.

You assume a direction of flight into the center of the frame. But it might as well be heading out of frame.
Title: Re: Fairing reuse
Post by: kevinof on 05/02/2018 04:11 pm
My assumption (as a sailor), was that it's moving left to right, with the nose rigged purposely high in the event it still has forward velocity when it lands. That way is minimizes water intake into the inside.

New instagram post from Elon Musk:

https://www.instagram.com/p/BiQ5qXnA_OM/?taken-by=elonmusk

Is it traveling wrong-end-first? I had pictured the top of the fairing headed into the wind.

You assume a direction of flight into the center of the frame. But it might as well be heading out of frame.
Title: Re: Fairing reuse
Post by: Skybert on 05/02/2018 06:07 pm
Long time lurker, first time poster...

I'm a paraglider pilot and my first reaction to the instagram photo is that it is travelling out of frame. A paraglider has a curved leading edge and often a more or less strait trailing edge. The curved leading edge gives the glider inherent yaw stability.

I think we can see the curved leading edge in the photo.
Title: Re: Fairing reuse
Post by: Swoopert on 05/02/2018 06:43 pm
Long time lurker, first time poster...

I'm a paraglider pilot and my first reaction to the instagram photo is that it is travelling out of frame. A paraglider has a curved leading edge and often a more or less strait trailing edge. The curved leading edge gives the glider inherent yaw stability.

I think we can see the curved leading edge in the photo.

Freefall parachutes tend to the opposite, to aid opening at terminal velocity, which is a characteristic I would expect this parachute to share. Having said that, I agree that this one does look like it's travelling to the right in this picture. I don't think that we can resolve enough of the image to determine the shape of the edges in this case  (maybe its my bias showing, but i actually see an elliptical trailing edge on the left), but I would bet that the slight triangular bulge on the lower side at the right is the right-hand stabiliser, a non load bearing piece of material that ensures the parachute flies straighter as it opens.
Title: Re: Fairing reuse
Post by: Jnkb on 05/03/2018 05:11 am
New instagram post from Elon Musk:

https://www.instagram.com/p/BiQ5qXnA_OM/?taken-by=elonmusk
Do we know from which mission is that landing?
Title: Re: Fairing reuse
Post by: john smith 19 on 05/03/2018 06:36 am
It looks like the sound insulation is applied in the form of individual panels which have some kind of bright reflective edging.  Does anyone know why that would be?  The more obvious way to do it would be to spray foam on the inside, as was done on the outside of the Space Shuttle external tank.

Yeah, that would make a nice and clean environment for spacecraft

A pair of sarc tags probably would have helped here, but I see the software deletes them automatically.:(

Spray on foam is fine for a) Covering large complex areas cheaply b) Not being too worried if any of the surface chips off.
However the insides of payload fairings are (relatively) small and foam fragments dropping into a mechanism (like one of the myriad that control antenna or cell array deployment) are a serious risk to the payload working properly.  Foam insulation is wanted, but at the same time you want the surface to be protected, hence the metal foil.
TBH I'm not really sure how effective that foam really is. It probably cuts the temperature range a bit and some high frequency noise, but a lot of the rocket noise is low frequency, long wavelength stuff. Below 1KHz a foam layer would be 13 inches thick to be 1 wavelength thick.
IMHO they'd be better off evacuating the shell and soft mounting the satellite (such techniques were developed originally for launching payloads on re-purposed ICBM stages with notoriously harsh rides. Soft mounts are used a bit but evacuation never took off. Presumably the tolerances were too tough for a single use object. But a reusable fairing...).
Title: Re: Fairing reuse
Post by: speedevil on 05/03/2018 12:02 pm
Below 1KHz a foam layer would be 13 inches thick to be 1 wavelength thick.
This assumes the speed of sound in porous absorbers is 340m/s.

This thread (https://www.gearslutz.com/board/bass-traps-acoustic-panels-foam-etc/665968-sound-speed-porous-absorbers.html) claims 111m/s or so may be more realistic, and gives some references I haven't chased up in the literature.

As another point, filling the fairing with Xenon about halves the speed of sound, and filling it with R22 approaches a third.

Evacuation makes the fairing unfortunately heavier.
For a 5.4m diameter fairing, that's around the equivalent stresswise of the whole rocket sitting on it, admittedly symmetrically, but it's going to get quite a lot heavier.
Title: Re: Fairing reuse
Post by: Sohl on 05/03/2018 04:19 pm

As another point, filling the fairing with Xenon about halves the speed of sound, and filling it with R22 approaches a third.


Isn't Xenon pretty expensive?  Would filling that big volume cost more than the fairing itself, and not be recoverable?
Title: Re: Fairing reuse
Post by: IanThePineapple on 05/03/2018 05:29 pm

As another point, filling the fairing with Xenon about halves the speed of sound, and filling it with R22 approaches a third.


Isn't Xenon pretty expensive?  Would filling that big volume cost more than the fairing itself, and not be recoverable?

Xenon is very heavy and very expensive
Title: Re: Fairing reuse
Post by: speedevil on 05/03/2018 06:35 pm

As another point, filling the fairing with Xenon about halves the speed of sound, and filling it with R22 approaches a third.


Isn't Xenon pretty expensive?  Would filling that big volume cost more than the fairing itself, and not be recoverable?

It's pretty expensive, yes, $1M/fairing. It was more of an aside than a serious suggestion. R22 in principle is nearly free, as a well as almost as nonreactive if that is a concern.

Liftoff weight would increase by around a ton, but as it would mostly be gone by 10km altitude, penalty is limited.

The main point was you probably can't assume speed of sound in air is identical to speed of sound in your foam.
Title: Re: Fairing reuse
Post by: Raul on 05/03/2018 08:09 pm
New instagram post from Elon Musk:   https://www.instagram.com/p/BiQ5qXnA_OM/?taken-by=elonmusk
Do we know from which mission is that landing?
It's very probably recent TESS mission. Definitely fairing 2.0.
Title: Re: Fairing reuse
Post by: john smith 19 on 05/04/2018 07:21 am
Below 1KHz a foam layer would be 13 inches thick to be 1 wavelength thick.
This assumes the speed of sound in porous absorbers is 340m/s.

This thread (https://www.gearslutz.com/board/bass-traps-acoustic-panels-foam-etc/665968-sound-speed-porous-absorbers.html) claims 111m/s or so may be more realistic, and gives some references I haven't chased up in the literature.

As another point, filling the fairing with Xenon about halves the speed of sound, and filling it with R22 approaches a third.

Evacuation makes the fairing unfortunately heavier.
For a 5.4m diameter fairing, that's around the equivalent stresswise of the whole rocket sitting on it, admittedly symmetrically, but it's going to get quite a lot heavier.
Thank you for that. I have learned something genuinely new I did not realize.  :)

If we're talking cheap inert gases Argon is the #1 choice as it's the biggest fraction of the atmosphere and it's used in welding.

OTOH if high molecular weight is the thing then I'd guess SF6, used in switchgear arc suppression is also pretty good.  Atomic mass of 84.
Title: Re: Fairing reuse
Post by: Jim on 05/04/2018 02:23 pm
Evacuation makes the fairing unfortunately heavier.
For a 5.4m diameter fairing, that's around the equivalent stresswise of the whole rocket sitting on it, admittedly symmetrically, but it's going to get quite a lot heavier.

Also, there would be no way to provide cooling to the spacecraft. 
Using gases other than air or GN2 are non starters due to the volume of gas required.  The conditioned gas is not recirculated.
Title: Re: Fairing reuse
Post by: LouScheffer on 05/04/2018 04:02 pm

Also, there would be no way to provide cooling to the spacecraft. 
Using gases other than air or GN2 are non starters due to the volume of gas required.  The conditioned gas is not recirculated.
Both of these are reasonable objections, but they are mutually exclusive.

If the gas is contained within the fairing, then you have cooling problems, but don't need huge volumes of gas

if you pass the gas through the fairing, then vent it, then you need a lot of gas, but you can cool it.
Title: Re: Fairing reuse
Post by: OxCartMark on 05/05/2018 12:09 am
If you were going to put an expensive or exotic gas into the fairing (which seems not likely to me) and you wanted to maintain the temperature of that gas it wouldn't take much effort to circulate it in and out now would it.  One big fat flexible duct with the gas going in and one big fat flexible duct with the gas going back out.  Round and round it goes until around the time that someone lights a fire at the bottom of the thing.  Doesn't seem like rocket science.  Isn't Spacex using air conditioning units from commercial buildings to supply conditioned air to the payload fairing?  If so they've got an inlet port and an outlet port on them already, just need the same in the fairing.
___________

OTOH if high molecular weight is the thing then I'd guess SF6, used in switchgear arc suppression is also pretty good.  Atomic mass of 84.
That would be ~900 kg. of SF6 at the moment it starts off.  That's a bunch!  And, it seems to me that its more like 146 gm / mol.
Title: Re: Fairing reuse
Post by: Slarty1080 on 05/05/2018 10:11 pm
If you were going to put an expensive or exotic gas into the fairing (which seems not likely to me) and you wanted to maintain the temperature of that gas it wouldn't take much effort to circulate it in and out now would it.  One big fat flexible duct with the gas going in and one big fat flexible duct with the gas going back out.  Round and round it goes until around the time that someone lights a fire at the bottom of the thing.  Doesn't seem like rocket science.  Isn't Spacex using air conditioning units from commercial buildings to supply conditioned air to the payload fairing?  If so they've got an inlet port and an outlet port on them already, just need the same in the fairing.
___________

OTOH if high molecular weight is the thing then I'd guess SF6, used in switchgear arc suppression is also pretty good.  Atomic mass of 84.
That would be ~900 kg. of SF6 at the moment it starts off.  That's a bunch!  And, it seems to me that its more like 146 gm / mol.

Not very environmentally friendly either, 900Kg SF6 has a global warming potential equivalent to more than 20,000 tons of C02, dwarfing the emissions from the F9 launch itself by well in excess of an order of magnitude.
http://www2.dmu.dk/1_Viden/2_miljoe-tilstand/3_luft/4_adaei/greenhouse_gases_en.asp

Title: Re: Fairing reuse
Post by: Jim on 05/06/2018 01:59 pm

Also, there would be no way to provide cooling to the spacecraft. 
Using gases other than air or GN2 are non starters due to the volume of gas required.  The conditioned gas is not recirculated.
Both of these are reasonable objections, but they are mutually exclusive.

If the gas is contained within the fairing, then you have cooling problems, but don't need huge volumes of gas

if you pass the gas through the fairing, then vent it, then you need a lot of gas, but you can cool it.

The gas has to be cooled.  No way around it.
Title: Re: Fairing reuse
Post by: Jim on 05/06/2018 02:04 pm
If you were going to put an expensive or exotic gas into the fairing (which seems not likely to me) and you wanted to maintain the temperature of that gas it wouldn't take much effort to circulate it in and out now would it.  One big fat flexible duct with the gas going in and one big fat flexible duct with the gas going back out.  Round and round it goes until around the time that someone lights a fire at the bottom of the thing.  Doesn't seem like rocket science.

It is.  The system is not gas tight.  Also the exit duct is an issue.  The fairing is blown to the top of the fairing where it basically "showers" down around the spacecraft equally.  There is no way of making a lightweight efficient return that is not going to have high velocities near the spacecraft.
Title: Re: Fairing reuse
Post by: Torbjorn Larsson, OM on 05/06/2018 05:36 pm
Seems odd to sit on top of an immensely large, immensely cooled set of cans, and be worried about cooling.

Can't the cargo sit on a cool plate (lots of "coolant" accessible below) and be conductivity cooled instead? What satellite designs, say, would make that problematic?
Title: Re: Fairing reuse
Post by: Welsh Dragon on 05/06/2018 05:58 pm
Seems odd to sit on top of an immensely large, immensely cooled set of cans, and be worried about cooling.

Can't the cargo sit on a cool plate (lots of "coolant" accessible below) and be conductivity cooled instead? What satellite designs, say, would make that problematic?
What about cooling before you start fuelling? What if you need to heat the payload because it's winter?
Title: Re: Fairing reuse
Post by: deruch on 05/06/2018 06:14 pm
Seems odd to sit on top of an immensely large, immensely cooled set of cans, and be worried about cooling.

Can't the cargo sit on a cool plate (lots of "coolant" accessible below) and be conductivity cooled instead? What satellite designs, say, would make that problematic?

Even if it were possible, that would only help once the LOX (or other cold propellant) was loaded.  What about during integration, roll out/back, erection, on pad checks, etc.  For F9, the vehicle goes upright almost 24hrs before launch.  RP-1 is loaded starting at T-70 minutes and LOX loading only starts at T-35 minutes. 
Title: Re: Fairing reuse
Post by: OxCartMark on 05/06/2018 09:43 pm
There is no way of making a lightweight efficient return that is not going to have high velocities near the spacecraft.
No.
Title: Re: Fairing reuse
Post by: LouScheffer on 05/06/2018 11:02 pm
Also the exit duct is an issue.  The fairing is blown to the top of the fairing where it basically "showers" down around the spacecraft equally.  There is no way of making a lightweight efficient return that is not going to have high velocities near the spacecraft.
On launch, the entire air contents of the fairing flow out through the vents at the bottom of the fairing, in a period of about a minute.  The spacecraft must be designed to withstand this.

This implies you could recirculate the air about once per minute, starting at the top and exiting through the existing vents, without exceeding the winds that the spacecraft already withstands.  That should be plenty for cooling.

However, just because it's technically possible does not make it a good idea.  I can't see any problem (cooling, noise, etc.) for which this is the simplest solution.
Title: Re: Fairing reuse
Post by: zodiacchris on 05/07/2018 08:24 am
Gentlemen, order please, going off topic double quick here... ::)
Title: Re: Fairing reuse
Post by: wannamoonbase on 05/08/2018 04:15 pm
New instagram post from Elon Musk:   https://www.instagram.com/p/BiQ5qXnA_OM/?taken-by=elonmusk
Do we know from which mission is that landing?
It's very probably recent TESS mission. Definitely fairing 2.0.

Is it safe to assume now that they have the parafoil deployment figured out?

They had a successful landing on the west coast and this one looks like it was flying beautifully.

They could be very close to successfully catching one of these $2.5 million dollar halves.
Title: Re: Fairing reuse
Post by: Cheapchips on 05/12/2018 10:50 am

I think there's some cost justification scattered throughout the thread, but thought it was worth stating the approx. 300 block 5 flights before retirement gives a clearer scope of cost saving. 

We still need to see if they get more than 1 reuse out of a fairing pair.   
Title: Re: Fairing reuse
Post by: speedevil on 05/12/2018 11:33 am

I think there's some cost justification scattered throughout the thread, but thought it was worth stating the approx. 300 block 5 flights before retirement gives a clearer scope of cost saving. 

We still need to see if they get more than 1 reuse out of a fairing pair.   

The implication of
Quote
a marginal cost for a Falcon 9 launch down, fully considered, down under five or six million dollars.
is that fairing, as well as S2 must be reused quite a lot - possibly the interstage too.

Title: Re: Fairing reuse
Post by: deruch on 05/12/2018 11:04 pm
The implication of
Quote
a marginal cost for a Falcon 9 launch down, fully considered, down under five or six million dollars.
is that fairing, as well as S2 must be reused quite a lot - possibly the interstage too.

I don't think Elon's quote is meant to be fine grained enough to include amortization.  More of the style of, If you have recovered hardware they are free to reuse.  So, not taking into account the cost of production being split over the total number of uses.  IMO, that 5-6M$ is for trajectory planning and mission management, refurbishment of recovered hardware, payload handling/encapsulation, range fees, launch staff labor costs, propellants and other consumables, operations costs for recovery (e.g. SpaceX fleet movements), and any other such type costs.

Otherwise the number of reuses on each recovered hardware element must be pretty massive to get low enough when including all the unique mission costs.  I just can't see how it could be done if the amortized costs are included.
Title: Re: Fairing reuse
Post by: dglow on 05/13/2018 12:00 am
from this transcript (https://gist.github.com/theinternetftw/5ba82bd5f4099934fa0556b9d09c123e):


Caleb Henry, SpaceNews: Hey Elon. Question about the price range that you talked about long term for the Falcon 9. You mentioned five to six million dollars. When do you project being able to provide those prices?

Elon Musk: Yeah. I do want to emphasize that those are long term marginal cost of flight. So those aren't prices, they're margin cost of flight, long term. Meaning it would take, I don't know, three years or so to get there. And then we are going to need to, we still have a bunch of fixed costs to cover, that need to be divided over that number of flights. And we need to recover the development costs of recovery. And pay for BFR. And pay for the Starlink constellation. So we do expect to see a steady reduction in prices, and we already have reduced prices from where they were, from about $60 million to about $50 million for a re-flown booster.  ...
Title: Re: Fairing reuse
Post by: dwheeler on 05/13/2018 01:15 am
Has it been confirmed that both fairing halves were recovers intact? It appears they’re both on the boat...

This video shows it.

https://www.youtube.com/watch?v=o-KgAhtXcMI

I forgot to ask at the time... Provided that both halves were recovered, do we think both had the full recovery system (parafoil, control system, etc)? And if not... the one without it (under the tarp) didn't seem too badly damaged considering it just fell back from space (not orbital velocity but still...)

Title: Re: Fairing reuse
Post by: john smith 19 on 05/13/2018 12:12 pm
from this transcript (https://gist.github.com/theinternetftw/5ba82bd5f4099934fa0556b9d09c123e):
Thanks for that transcript. Good find.


Lots of interesting stuff there.

Titanium grid fins are now SOP.
Legs have retraction actuators (something Shuttle never managed)
New TPS on end of stage that is not composite and hydrophobic. Used for interstage, raceways and landing legs. I'm wondering if they went with the Grumman material proposed for the Shuttle, basically a kind of autoclaved aerated concrete. Closed cell ceramic foam.
The Octaweb going to 7xxx Al alloy over 2xxx. IIRC 2xxx tend to be used due to good cryogenic strength. Not an issue around the engine bays.
Lastly moving replacing a CFRP with a Titanium heat shield with descent water cooling.

It was interesting Musk mentioned the safety factor for crewed flght was 40% and 25% for non crewed flight as I seemed to recall one of F9's selling points was it was designed to a safety factor of 1.4 already.

I see that US recovery is back on the agenda. I guess the science models have collected a bit more information to suggest it may be doable this time.

It was a pity no one asked if they were looking at a Methane F9, or Methane US, but given how adamant Musk was about this being the last upgrade that would have been well beyond the current design.

Very interesting, and lots to unpack. 

Title: Re: Fairing reuse
Post by: JamesH65 on 05/13/2018 09:35 pm
from this transcript (https://gist.github.com/theinternetftw/5ba82bd5f4099934fa0556b9d09c123e):
Thanks for that transcript. Good find.


Lots of interesting stuff there.

Titanium grid fins are now SOP.
Legs have retraction actuators (something Shuttle never managed)
New TPS on end of stage that is not composite and hydrophobic. Used for interstage, raceways and landing legs. I'm wondering if they went with the Grumman material proposed for the Shuttle, basically a kind of autoclaved aerated concrete. Closed cell ceramic foam.
The Octaweb going to 7xxx Al alloy over 2xxx. IIRC 2xxx tend to be used due to good cryogenic strength. Not an issue around the engine bays.
Lastly moving replacing a CFRP with a Titanium heat shield with descent water cooling.

It was interesting Musk mentioned the safety factor for crewed flght was 40% and 25% for non crewed flight as I seemed to recall one of F9's selling points was it was designed to a safety factor of 1.4 already.

I see that US recovery is back on the agenda. I guess the science models have collected a bit more information to suggest it may be doable this time.

It was a pity no one asked if they were looking at a Methane F9, or Methane US, but given how adamant Musk was about this being the last upgrade that would have been well beyond the current design.

Very interesting, and lots to unpack.

I suspect that some of their first stage experimental high energy returns (albeit much lower energy than the 2nd stage) may have given them some more data to tweak their models, and the results are making S2 return more feasible.
Title: Re: Fairing reuse
Post by: Torbjorn Larsson, OM on 05/13/2018 11:11 pm
Legs have retraction actuators (something Shuttle never managed)

FWIW, you make it sound like the legs carry those actuators. (But they are likely not even on the barge, but placed at the harbor for the leg stowing ops.)

What legs did the Shuttle need to retract? The wheel legs?

EDIT: I just saw that this thread was titled fairing reuse, so never mind my question.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 05/14/2018 01:15 pm
Quote
It does not appear that GO Pursuit will be offloading the catch any time soon. A preview from my camera shows at least one fairing half under the brown tarp. Phone snaps show the grey day that promises to stick around. #SpaceXFleet

https://twitter.com/julia_bergeron/status/996015083904958465
Title: Re: Fairing reuse
Post by: mme on 05/14/2018 03:13 pm
Quote
It does not appear that GO Pursuit will be offloading the catch any time soon. A preview from my camera shows at least one fairing half under the brown tarp. Phone snaps show the grey day that promises to stick around. #SpaceXFleet

https://twitter.com/julia_bergeron/status/996015083904958465
They are getting good at this. I wonder when the east coast will get it's own bouncy castle.
Title: Re: Fairing reuse
Post by: envy887 on 05/14/2018 06:20 pm

Legs have retraction actuators (something Shuttle never managed)


What does shuttle have to do with anything?

That's not even true for F9. Elon didn't say the legs can actuate retraction by themselves, he said that they can be easily folded and latched, implying it's still a manual process - just a faster one than before.

Quote
The landing legs, you'll notice if you look carefully that there are no outward scallops on the perimeter of the landing leg, which were used to clamp down the leg during ascent. We have now brought those features inside the leg itself. So you'll see sort of a cleaner outer contour. And it has an internal latch mechanism that can be opened and closed repeatedly with ease. So essentially deploying the landing gear and stowing the landing gear is now a very ease thing to do, whereas previously it required several hours to re-stow the landing gear. Which can now be done with an actuator, pretty easily.
Title: Re: Fairing reuse
Post by: lrk on 05/14/2018 07:41 pm

New TPS on end of stage that is not composite and hydrophobic. Used for interstage, raceways and landing legs. I'm wondering if they went with the Grumman material proposed for the Shuttle, basically a kind of autoclaved aerated concrete. Closed cell ceramic foam.


I'm pretty sure this is the wrong thread for such discussion.  But just FYI, there is L2 info on this from a few months ago. 
Title: Re: Fairing reuse
Post by: Lar on 05/14/2018 09:02 pm
Stage TPS? Legs? Wrong thread.
Title: Re: Fairing reuse
Post by: YEGLego on 05/17/2018 02:21 am
(https://i.imgur.com/xx2Ywm9.jpg)

From reddit user /u/kegman83: "Brother works down at the LA docks, snapped this picture this morning. Any ideas?"

It shows the new yellow net underneath, and there was supposedly a drop test recently.
Title: Re: Fairing reuse
Post by: Inoeth on 05/17/2018 03:49 am
https://twitter.com/w00ki33/status/996950927717232640

She works for Teslarati as one of their west coast photographers. It looks like Mr Steven did a number of loops around the ocean at speed with the fairing but apparently no drop-tests have actually taken place yet.
Title: Re: Fairing reuse
Post by: Lars-J on 05/18/2018 06:07 am
I'm skeptical about the merit of fairing reuse. It is something every other launchers can implement at any time. The development cost is not prohibitive, there is nothing that would prevent its development. But nobody has try in space flight history.
 I guess it's just a marketing gimmick by elon musk. The question would be how much added cost they can tolerate rather than how much it can save.

Nobody has tried fairing recovery because up 'til recently no one was doing trying to reuse *anything*.  :)  (The Shuttle excluded of course, but that did more to scare people off reuse than advance the cause)

SpaceX does try a lot of things, some work out, some do not. But it is worth it to them to at least give it a good try, and then determine if it makes sense to continue. It is after all not going to be a technology that is useful for BFR, since that system has no faring at all.
Title: Re: Fairing reuse
Post by: woods170 on 05/18/2018 07:57 am
I'm skeptical about the merit of fairing reuse. It is something every other launchers can implement at any time. The development cost is not prohibitive, there is nothing that would prevent its development. But nobody has try in space flight history.
 I guess it's just a marketing gimmick by elon musk. The question would be how much added cost they can tolerate rather than how much it can save.

It is very simple: as long as the total cost involved for recovering a single fairing -half is significantly lower than $3 million, than fairing recovery - and reuse - is absolutely worth it.

Musk is expecting a further 300 flights of F9 before F9 is retired. Now, assume that on HALF of those missions they manage to recover one fairing half. That constitutes 150 fairing halfs, at $3 million a piece. That is a potential savings of $450 million, assuming that a recovered fairing is reused just once. When recovered fairings go the way of F9S1, than the savings begin to accumulate to an even bigger amount of money.
Title: Re: Fairing reuse
Post by: deruch on 05/18/2018 08:00 am
I'm skeptical about the merit of fairing reuse. It is something every other launchers can implement at any time. The development cost is not prohibitive, there is nothing that would prevent its development. But nobody has try in space flight history.
 I guess it's just a marketing gimmick by elon musk. The question would be how much added cost they can tolerate rather than how much it can save.

Wrong in a bunch of ways. 

1.  a)SpaceX fairings are significantly different from other manufacturers'.  Because of the way that SpaceX has chosen to horizontally integrate the encapsulated payloads with their rockets, their fairings are built to support much higher forces than is normal (i.e. weight of the payload is, at times, supported by the fairing).  This means that they are much more rigid (as well as heavier).  And as a result, they may have a distinct advantage over other fairings in controllably surviving reentry without as much modification.  To see this difference, watch how wobbly/flappy other fairings are on jettison.
    b)The F9 and FH are quite overpowered for most of their manifested launches and therefore are perfectly happy to drag along a fairing that is significantly heavier than absolutely necessary when strictly considering payload protection during ascent.  They are equally happy to accept the added weight needed for recovery systems.  Other fairing makers may find this to be less true for other LVs, whether those LVs have the same excess performance or not.   
2.  With respect to fairing recovery/reuse and why all others haven't already done so before, much more than other launch companies, SpaceX has vigorously striven to lower their launch costs.  This has played out in a number of effects, pursuit of reuse is just one.  Frankly, that they are more aggressively pursuing any savings to be found in fairing reuse shouldn't come as a surprise to anyone watching the launch industry in recent years.
3.  SpaceX has a distinct advantage because they are a vertically integrated business that does so much in-house.  Because they make their own fairings, all savings achieved via recovery/reuse are captured by the company.  The largest benefit of fairing recovery/reuse may be that it can save you from having to build additional production lines.  This is only really seen when approaching the build limit of your current fairing production line(s).  So, while the marginal production cost on individual fairings may actually be higher to account for the additional recovery hardware, SpaceX is likely going to be saving quite significantly on total fixed costs in order to support their very high launch rate. 
4.  SpaceX's vertical (business) integration also has significant benefits in both the R&D phase and in operations.  All hardware changes and flight testing decisions can be approved in-house.  The speed at which they can make changes and flight test them is significantly reduced.  Which means the cost to actually develop this technology will be reduced.
5.  SpaceX's research and development funding pool is likely much higher than any company that just makes fairings.  So, they can afford to spend much more upfront for a smaller per fairing savings recovered over a longer period or over more launches. 
6.  Other companies/organizations have looked into fairing recovery/reuse.  SpaceX isn't the only one, even if they're the only ones to have gotten as far as flight testing yet (see earlier points on why that may be).  Here's a presentation by RUAG in 2016 (references work starting in 2015) on fairing reuse [power point warning]. (https://www.spacesymposium.org/sites/default/files/tt_papers/Wiesendanger%2C%20Andreas-Presentation-RUAG_Reusable_PLF_April%202016-v1.5_final.pptx)

Plus, I'm sure others will add ways I haven't considered. 

Basically, in addition to some historical effects, a lot of the reasons why no one has really tried to achieve this before is because there has traditionally be a misalignment of incentives between the fairing makers and the launchers.
Title: Re: Fairing reuse
Post by: UKobserver on 05/18/2018 09:13 am
I'm skeptical about the merit of fairing reuse. It is something every other launchers can implement at any time. The development cost is not prohibitive, there is nothing that would prevent its development. But nobody has try in space flight history.
 I guess it's just a marketing gimmick by elon musk. The question would be how much added cost they can tolerate rather than how much it can save.
I think there are two separate questions here;
a) Why has no-one tried this before, and
b) Why is Elon trying it now.

I think the answer to a) is partly that people drew the wrong lessons from shuttle, as Lars-J suggested, assuming that re-use would make rockets uneconomical. But I think the main answer to a) is that, in the specific case of fairing re-use, no-one would ever have started with that part of the rocket as it represents such a small percentage of the overall cost/price, and the actual dollar value saving is very low when considering legacy launch prices.

Consider Atlas 5 at ~$150-225m and that re-use might save $5m of that. It's not peanuts, but it's a tiny saving when you consider that they would have to persuade a spendthrift board of directors to spend money on a development that wont likely generate the company any additional revenue if it succeeds (the effect of reducing such a high price by such a small amount can be assumed to be negligible) and also persuade them to risk a reputation based almost entirely on reliability for no clear benefit to the company. They would also have then had to persuade a very risk-averse customer to let them experiment during the launch of incredibly expensive and mission-critical payloads. It is easy to imagine that they would conclude that it was not worth even trying. For them, it genuinely would have only been a marketing gimmick and securing a bit of professional kudos for the engineers.

So why are SpaceX trying it now?

Elon is undoubtedly very good at leveraging the excitement of demonstrating new technologies to market his companies, and it's clear that being part of such a history-making team is very motivating for his employees, and allows SpaceX to attract top talent while keeping costs lower than any other company, but he's also demonstrated that he doesn't make changes just for their own sake; they have to advance the goals of the company in some real way. If it becomes obvious that they are not advancing that overall objective then they get dropped like a hot potato, even if that means writing off time, effort and cost. Propulsive landing on Dragon is a clear example of this. So there must be some other reason in addition to marketing.

Now one could argue that having succeeded in reducing the total cost of the Falcon 9 to around half the price of it's competitors, through clever design and in-house fabrication of a very high proportion of components, that they have no need to reduce the price any further because any sane customer will just pay the $62m to save themselves at least another $50m that they would spend launching with a competitor. One could argue that SpaceX would basically just be denying themselves additional revenue.

But consider fairing use from these perspectives;

Philanthropic goal;
Firstly they have a stated philanthropic goal of massively reducing the cost of space launch in order to make it accessible and affordable for all humanity. On it's own that means they will at least consider reducing the cost of their rocket purely so that they can pass those savings on to customers, and encourage the expansion of the space economy. They do of course have to balance that desire against funding the ongoing expansion and development of the company, hence why they are not passing on all the savings they are making on first-stage re-use to their customers, but they have nevertheless dropped the price by $10m, whilst pocketing some additional launch profit to fund their R&D.

But they also have a very beady eye on the massive challenge that they are about to confront of launching a huge constellation of Starlink satellites. Setting aside the development of the actual constellation technology itself, consider two additional aspects of that challenge;

Manufacturing capacity;
They are going to require a phenomenal launch rate to loft that number of satellites in the time period they have been set. Producing so many fairings so quickly poses a huge manufacturing challenge, both in building a workforce capable of doing it and buying the equipment/facility space to allow it. Re-use offers the prospect of massively reducing that engineering challenge and capital cost. Even just using each fairing a second time would be a huge win, so imagine if they could re-use them 10 times. Suddenly that manufacturing and launch rate seems a bit more achievable. Imagine if they had to build that many first stage boosters as well? Re-use of first stages has gone a long way to giving them confidence that they can physically make enough boosters to launch the constellation. That still leaves the lesser (but still big enough) challenge of manufacturing enough 2nd stages, which is why they are now revisiting the idea of trying to recover and re-use that stage too. Any component that they can successfully re-use is capital that they don't have to spend on manufacturing capacity, and also frees up those personnel and their wages to start constructing BFR, which they are almost entirely funding internally remember.

Starlink deployment capital:
Finally, consider how much it would cost SpaceX to launch their constellation of Starlink satellites if the rockets weren't reusable; If we assume that they are making a 20% profit on each launch (which they reinvest in R&D) and that the actual cost of each new rocket (1st stage, 2nd stage, fairing, fuel and launch costs) is about $50m (it may be a bit lower), then it would require an enormous amount of money to launch the 12,000 satellites they have planned. Even at 20 per launch that would be 600 launches, or $30bn. And that's just the capital required to build, fuel and launch the rockets, not even considering the cost of developing and then manufacturing the satellites themselves. Even if they were able to re-use the first and 2nd stages infinitely and it was just a brand new fairing they needed for each constellation launch, that would still be an enormous amount of money, all of which they may have to fund internally, from profits made on commercial/military launches, if they can't persuade external investors. They just don't have that sort of money. It's not even conceivable as a project unless they can get those costs down. But now consider the possibility that maybe the entire rocket could be re-used 10 times and suddenly the start-up capital required for launching the constellation drops to perhaps 10% of what it was, fuel and launch services being a small percentage of overall costs. 10 uses might not be achievable for all components, but they are aiming for an even higher number of flights with first stage re-use, so decreasing costs by a factor of 10 already seems achievable.

If I had to guess, it would be the need for those massive capital savings when they launch Starlink that is driving the urgency to perfect fairing re-use and get started on 2nd stage experimentation.
Title: Re: Fairing reuse
Post by: johnfwhitesell on 05/18/2018 04:30 pm
I dont think the financial impact of fairing reuse is going to be important for starlink.  Suppose that starting in 2019 half their fairings are recycled.  That's maybe 90 flights * 3 million saved per flight before starlink is lighting up.  270 million is a nice chunk of change but you have to subtract from that the development and operational costs of the reuse.  And this money is mostly showing up towards the end of the time period.  Maybe it will allow for starlink to happen a little bit faster but I think the benefits are mostly long term, especially the experience with a different form of reentry.
Title: Re: Fairing reuse
Post by: aero on 05/18/2018 04:41 pm
I wonder if we are overlooking something? Perhaps the calendar time needed to build 90 new fairings vs. the calendar time needed to recover and re-use most of the fairings needed is a consideration?
Title: Re: Fairing reuse
Post by: edzieba on 05/18/2018 05:00 pm
It's probably the main consideration. Fairing production is already a bottleneck in flight rate: each half needs two separate complex monolithic Carbon fibre layups (big ones too), then for the two to be bonded together with an aluminium honeycomb sandwiched in-between, then all the associated flight hardware (latches, pushers, HVAC ducting, sound-deadening and insulation, RCS, parachutes, GNC, etc) installed. Every fairing you can re-use is a fairing you don't need to wait to be manufactured before you can fly.
It's not impossible that the costs of developing fairing re-use are comparable to the cost of setting up an additional parallel production line for fairing halves (floorspace, equipment, staffing, etc).
Title: Re: Fairing reuse
Post by: John Santos on 05/18/2018 05:21 pm
I'm skeptical about the merit of fairing reuse. It is something every other launchers can implement at any time. The development cost is not prohibitive, there is nothing that would prevent its development. But nobody has try in space flight history.
 I guess it's just a marketing gimmick by elon musk. The question would be how much added cost they can tolerate rather than how much it can save.
I think there are two separate questions here;
a) Why has no-one tried this before, and
b) Why is Elon trying it now.

I think the answer to a) is partly that people drew the wrong lessons from shuttle, as Lars-J suggested, assuming that re-use would make rockets uneconomical. But I think the main answer to a) is that, in the specific case of fairing re-use, no-one would ever have started with that part of the rocket as it represents such a small percentage of the overall cost/price, and the actual dollar value saving is very low when considering legacy launch prices.

Consider Atlas 5 at ~$150-225m and that re-use might save $5m of that. It's not peanuts, but it's a tiny saving when you consider that they would have to persuade a spendthrift board of directors to spend money on a development that wont likely generate the company any additional revenue if it succeeds (the effect of reducing such a high price by such a small amount can be assumed to be negligible) and also persuade them to risk a reputation based almost entirely on reliability for no clear benefit to the company. They would also have then had to persuade a very risk-averse customer to let them experiment during the launch of incredibly expensive and mission-critical payloads. It is easy to imagine that they would conclude that it was not worth even trying. For them, it genuinely would have only been a marketing gimmick and securing a bit of professional kudos for the engineers.


I think you mean the opposite :).  "Spendthrift" means profligate or wasteful. Otherwise, totally agree.
Title: Re: Fairing reuse
Post by: Kansan52 on 05/18/2018 06:32 pm
Another 'cost' is the length of time to build a fairing. Sure, he could buy more property and hire more people and train more people, ect to increase production but reuse ) speeds that process.
Title: Re: Fairing reuse
Post by: deruch on 05/18/2018 06:46 pm
I wonder if we are overlooking something? Perhaps the calendar time needed to build 90 new fairings vs. the calendar time needed to recover and re-use most of the fairings needed is a consideration?

Time is money.  That's just another way of saying that they are saving on costs by not having to set up an additional production line.  The only difference is that your way doesn't start with the increased flight rate as a given.  But it's really the same thing others have been saying from the beginning, just viewed from a slightly different direction.
Title: Re: Fairing reuse
Post by: obi-wan on 05/18/2018 09:31 pm
I'm skeptical about the merit of fairing reuse. It is something every other launchers can implement at any time. The development cost is not prohibitive, there is nothing that would prevent its development. But nobody has try in space flight history.
 I guess it's just a marketing gimmick by elon musk. The question would be how much added cost they can tolerate rather than how much it can save.

Wrong in a bunch of ways. 

1.  a)SpaceX fairings are significantly different from other manufacturers'.  Because of the way that SpaceX has chosen to horizontally integrate the encapsulated payloads with their rockets, their fairings are built to support much higher forces than is normal (i.e. weight of the payload is, at times, supported by the fairing).  This means that they are much more rigid (as well as heavier).  And as a result, they may have a distinct advantage over other fairings in controllably surviving reentry without as much modification.  To see this difference, watch how wobbly/flappy other fairings are on jettison.
{rest snipped because this is what I'm replying to}

I know this has been discussed before on this site, but no, no, NO!!! The fairing DOES NOT _EVER_ support the payload, on any vehicle, for any reason! Check out the payload user's guides for any launch vehicle, including F9. ALL the loads for the payload are taken through the payload attach fitting (PAF), which is the ring at the top of the upper stage to which the payload attaches (typically with a Marman band or other low-shock separation device). The payload volume is defined as a dynamic envelope which the payload can never exceed under the worst case loading. That's because the payload fairing will never enter that volume under its worst case loading. If the payload fairing ever touches the payload, you have an indeterminate loading condition where the payload is assuming some of the fairing loads, or vice versa. There is no way to predict the loads in that case, so there's no way to qualify the payload or fairing if that happens.

When the F9 is horizontal, the payload is cantilevered from the PAF. The fairing is cantilevered from its mounting fixture around the upper stage. Most launch providers have a very large piece of GSE that will hold the integrated fairing/payload cantilevered from the mounting face for integration to the launch vehicle if they use horizontal integration.

I can't say categorically that SpaceX does not use the fairing as a lifting point for payload integration, although that would require either that every fairing is designed for the mass and inertia of its specific payload, or that every fairing is designed to take the loads of the heaviest payload F9 is capable of flying, either of which would be surprising as compared to just making some GSE to take the loads. But I will say categorically that the payload never, ever touches the inside of the fairing, as payload designers would find it impossible to definitively calculate those loads and verify against the (nondeterministic) models.
Title: Re: Fairing reuse
Post by: deruch on 05/19/2018 09:29 am
I'm skeptical about the merit of fairing reuse. It is something every other launchers can implement at any time. The development cost is not prohibitive, there is nothing that would prevent its development. But nobody has try in space flight history.
 I guess it's just a marketing gimmick by elon musk. The question would be how much added cost they can tolerate rather than how much it can save.

Wrong in a bunch of ways. 

1.  a)SpaceX fairings are significantly different from other manufacturers'.  Because of the way that SpaceX has chosen to horizontally integrate the encapsulated payloads with their rockets, their fairings are built to support much higher forces than is normal (i.e. weight of the payload is, at times, supported by the fairing).  This means that they are much more rigid (as well as heavier).  And as a result, they may have a distinct advantage over other fairings in controllably surviving reentry without as much modification.  To see this difference, watch how wobbly/flappy other fairings are on jettison.
{rest snipped because this is what I'm replying to}
I can't say categorically that SpaceX does not use the fairing as a lifting point for payload integration, although that would require either that every fairing is designed for the mass and inertia of its specific payload, or that every fairing is designed to take the loads of the heaviest payload F9 is capable of flying, either of which would be surprising as compared to just making some GSE to take the loads. But I will say categorically that the payload never, ever touches the inside of the fairing, as payload designers would find it impossible to definitively calculate those loads and verify against the (nondeterministic) models.

This is what I was talking about.  Not that the payload ever touches the fairing but that loads are carried through it when, post encapsulation, they break it over from vertical to horizontal and then integrate it with the rocket.  Once it is integrated, the loads are either entirely or almost entirely carried by the rocket.  But SpaceX doesn't (or at least didn't in the past) use a specialized bit of GSE to keep all the forces running through the PAF.  They used the HIF cranes with lift points on the fairing which means the load path partially runs through the fairing.
Title: Re: Fairing reuse
Post by: Comga on 05/19/2018 08:25 pm
I'm skeptical about the merit of fairing reuse. It is something every other launchers can implement at any time. The development cost is not prohibitive, there is nothing that would prevent its development. But nobody has try in space flight history.
 I guess it's just a marketing gimmick by elon musk. The question would be how much added cost they can tolerate rather than how much it can save.

Wrong in a bunch of ways. 

1.  a)SpaceX fairings are significantly different from other manufacturers'.  Because of the way that SpaceX has chosen to horizontally integrate the encapsulated payloads with their rockets, their fairings are built to support much higher forces than is normal (i.e. weight of the payload is, at times, supported by the fairing).  This means that they are much more rigid (as well as heavier).  And as a result, they may have a distinct advantage over other fairings in controllably surviving reentry without as much modification.  To see this difference, watch how wobbly/flappy other fairings are on jettison.
{rest snipped because this is what I'm replying to}
I can't say categorically that SpaceX does not use the fairing as a lifting point for payload integration, although that would require either that every fairing is designed for the mass and inertia of its specific payload, or that every fairing is designed to take the loads of the heaviest payload F9 is capable of flying, either of which would be surprising as compared to just making some GSE to take the loads. But I will say categorically that the payload never, ever touches the inside of the fairing, as payload designers would find it impossible to definitively calculate those loads and verify against the (nondeterministic) models.

This is what I was talking about.  Not that the payload ever touches the fairing but that loads are carried through it when, post encapsulation, they break it over from vertical to horizontal and then integrate it with the rocket.  Once it is integrated, the loads are either entirely or almost entirely carried by the rocket.  But SpaceX doesn't (or at least didn't in the past) use a specialized bit of GSE to keep all the forces running through the PAF.  They used the HIF cranes with lift points on the fairing which means the load path partially runs through the fairing.
Please read the previous post with more care.
Your statements are false.
Title: Re: Fairing reuse
Post by: deruch on 05/20/2018 05:34 am
This is what I was talking about.  Not that the payload ever touches the fairing but that loads are carried through it when, post encapsulation, they break it over from vertical to horizontal and then integrate it with the rocket.  Once it is integrated, the loads are either entirely or almost entirely carried by the rocket.  But SpaceX doesn't (or at least didn't in the past) use a specialized bit of GSE to keep all the forces running through the PAF.  They used the HIF cranes with lift points on the fairing which means the load path partially runs through the fairing.
Please read the previous post with more care.
Your statements are false.

Here's the lift and breakover of the Jason-3 mission.

https://www.flickr.com/photos/nasakennedy/23776528834/
Quote
KSC-20160111-PH_TNN0001-0006

In the SpaceX Payload Processing Facility at Vandenberg Air Force Base in California, the Jason-3 satellite is fully encapsulated in its payload fairing. With this step complete, Jason-3 will be mated to a SpaceX Falcon 9 rocket at Vandenberg's Space Launch Complex 4. Built by Thales Alenia of France, Jason-3 will measure the topography of the ocean surface for a four-agency international partnership consisting of NOAA, NASA, Centre National d’Etudes Spatiales, France’s space agency, and the European Organization for the Exploitation of Meteorological Satellites.

https://www.flickr.com/photos/nasakennedy/24322264661/
Quote
KSC-20160111-PH_TNN0001-0007

In the SpaceX Payload Processing Facility at Vandenberg Air Force Base in California, the payload fairing containing the Jason-3 satellite has been rotated to horizontal in preparation for mating to a SpaceX Falcon 9 rocket at Vandenberg's Space Launch Complex 4. Built by Thales Alenia of France, Jason-3 will measure the topography of the ocean surface for a four-agency international partnership consisting of NOAA, NASA, Centre National d’Etudes Spatiales, France’s space agency, and the European Organization for the Exploitation of Meteorological Satellites.
Photo credits: NASA/Thiep Nguyen and Christopher Wiant

Maybe things have changed or, for heavier payloads, they do things differently but we haven't seen any evidence of this [excluding Dragon which is treated differently and does have a unique breakover fixture].  When coupled with the manner that they support the fairings during roll-out and while the rocket is horizontal on the pad prior to being erected, I think the point about load paths still stands.  Of course, if you have any evidence of relevant changes (even if it's just passed along info from those who have first hand knowledge) I'd be very interested to see/hear it.
Title: Re: Fairing reuse
Post by: OxCartMark on 05/24/2018 03:17 am
So I saw that the fairings went up and I saw them fall back down and I see that Mr. Steven is in port.  Those are the basic facts.  Can anyone fill in the details?
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 05/24/2018 07:00 am
Quote
Mr Steven returned to port around 7pm PST May 23 with both Iridium-6/GRACE-FO fairing halves aboard, by all appearances intact! Seawater immersion means no reuse, but they may find use as drop test articles to refine accuracy :D @NASAJPL @IridiumBoss @nextspaceflight @Teslarati

https://twitter.com/13ericralph31/status/999541304437571590

Quote
Given the fact that they seem to have figured out how to recovery fairings intact from the ocean surface, it's truly just a matter of time before @SpaceX engineers & techs refine the accuracy enough for Mr Steven to catch them out of the air. Live coverage included, perhaps...

https://twitter.com/13ericralph31/status/999541309713956864

Quote
Lastly, these incredible photos were taken by @chuckbennett (Instagram username is the same) a skilled photog & editor (you may recognize him from past work w/ The Daily Breeze). Meanwhile, @w00ki33 is heading down to capture the fairings from the docks, so very neo-noir 😁 🤞

https://twitter.com/13ericralph31/status/999541310695469056
Title: Re: Fairing reuse
Post by: john smith 19 on 05/24/2018 07:48 am
Quote
Mr Steven returned to port around 7pm PST May 23 with both Iridium-6/GRACE-FO fairing halves aboard, by all appearances intact! Seawater immersion means no reuse, but they may find use as drop test articles to refine accuracy :D @NASAJPL @IridiumBoss @nextspaceflight @Teslarati

https://twitter.com/13ericralph31/status/999541304437571590

Quote
Given the fact that they seem to have figured out how to recovery fairings intact from the ocean surface, it's truly just a matter of time before @SpaceX engineers & techs refine the accuracy enough for Mr Steven to catch them out of the air. Live coverage included, perhaps...

https://twitter.com/13ericralph31/status/999541309713956864

Quote
Lastly, these incredible photos were taken by @chuckbennett (Instagram username is the same) a skilled photog & editor (you may recognize him from past work w/ The Daily Breeze). Meanwhile, @w00ki33 is heading down to capture the fairings from the docks, so very neo-noir 😁 🤞
It's pretty clear that SX have made a lot of progress on fairing recovery. Those halves look in pretty good shape compared to the large chunks the last one I saw was in.  Obviously it's impossible to say what damage exposure to seawater has done to them so I guess they'll be off to the testing shop to find out.

I'd expect fairing recovery (at least) to be a routine procedure by the end of the year.  We might even see the first fairing reuse by then, depending on wheather post recovery testing shows up any issues.

While I think fairings have been recovered before (some of the early Ariane 5 SRB had recovery parachutes under the nose for inspection) I'm not sure how much analysis was done on them before SX, beyond a quick visual check along the lines of "Looks good. No obvious damage. We could probably use it again." Not using explosive bolts probably goes a long way to minimizing damage from the initial separation event.
Title: Re: Fairing reuse
Post by: JamesH65 on 05/24/2018 11:48 am
It does make you wonder that even if the shell cannot be used, how much of the cost is in fittings on it that can be reused. It might even be cost effective to recover and not use the shell, although I think that unlikely.
Title: Re: Fairing reuse
Post by: rsdavis9 on 05/24/2018 12:19 pm
So I assume because we have seen TWO intact fairings for the last couple of launches that they are putting recovery hardware on both halves?
Title: Re: Fairing reuse
Post by: woods170 on 05/24/2018 12:21 pm
So I assume because we have seen TWO intact fairings for the last couple of launches that they are putting recovery hardware on both halves?

Not an assumption but fact. Recovery hardware has been present on BOTH fairing halves on at least two recent missions.
Title: Re: Fairing reuse
Post by: edzieba on 05/24/2018 12:25 pm
Almost all the cost is going to be in the big composites (two separate CF layups, plus the sandwiching process of bonding an aluminium honeycomb between them). The other non-recovery hardware (i.e. latches, transducers for payload monitoring, valves for groundside HVAC) is comparatively pocket change, and probably costs less than the added recovery hardware like the RCS, GNC, and parachute system.
Title: Re: Fairing reuse
Post by: laszlo on 05/24/2018 12:36 pm
...Obviously it's impossible to say what damage exposure to seawater has done to them so I guess they'll be off to the testing shop to find out...

Preventing seawater damage to composite structures is a well-known technology. I wonder if it'd be cheaper to just build the fairings to tolerate seawater rather than coming up with all the elaborate boat-chasing hardware and procedures. Or are there spaceflight requirements that prevent essentially launching with a boat covering the payload?
Title: Re: Fairing reuse
Post by: deruch on 05/24/2018 12:39 pm
Plus the truly major savings is in forgoing the need to build out additional production lines to support raised launch rates.  Those added production lines are real killers in both tooling costs and square footage needs.  And if the increased launch rate isn't enough to make full use of the newly added capacity, then you end up with an inefficient investment as well.
Title: Re: Fairing reuse
Post by: Cheapchips on 05/24/2018 12:52 pm
...Obviously it's impossible to say what damage exposure to seawater has done to them so I guess they'll be off to the testing shop to find out...

Preventing seawater damage to composite structures is a well-known technology. I wonder if it'd be cheaper to just build the fairings to tolerate seawater rather than coming up with all the elaborate boat-chasing hardware and procedures. Or are there spaceflight requirements that prevent essentially launching with a boat covering the payload?

It's presumable not just exposure but physical damage too.  Water's much harder than a net.

Title: Re: Fairing reuse
Post by: john smith 19 on 05/24/2018 04:02 pm
Plus the truly major savings is in forgoing the need to build out additional production lines to support raised launch rates.  Those added production lines are real killers in both tooling costs and square footage needs.  And if the increased launch rate isn't enough to make full use of the newly added capacity, then you end up with an inefficient investment as well.
True.

The flip side of course is that if BFR is on schedule then there will not be a need to ramp up faring production as BFR will carry those payloads.

In which case this is something of a waste of time.

OTOH if BFR is late this will be a nice cost reduction contingency plan to fall back on (and allow more resources to be diverted to speeding up the BFR roll out).
Title: Re: Fairing reuse
Post by: DistantTemple on 05/24/2018 04:18 pm
With nearly 30 launches expected this year (about 20 left) but only 19 next year, there is a short term need now, so it makes even more sense to get reuse working and avoid increasing production facilities.

Assuming Starlink starts launching before BFR is flying... which seems very likely as BFR is at best only expected to do short hops etc during 2019, a lot of fairings, or lots of reuses of fairings, may suddenly be needed. But the timing of that and the overlap with early BFR is an unknown. So ISTM that fairing reuse in place well before that, should facilitate frequent Starlink flights without the cost or possible wait for new fairings, and definitely avoid more production facilities.
Title: Re: Fairing reuse
Post by: woods170 on 05/24/2018 06:56 pm
I know this has been discussed before on this site, but no, no, NO!!! The fairing DOES NOT _EVER_ support the payload, on any vehicle, for any reason! Check out the payload user's guides for any launch vehicle, including F9. ALL the loads for the payload are taken through the payload attach fitting (PAF), which is the ring at the top of the upper stage to which the payload attaches (typically with a Marman band or other low-shock separation device). The payload volume is defined as a dynamic envelope which the payload can never exceed under the worst case loading. That's because the payload fairing will never enter that volume under its worst case loading. If the payload fairing ever touches the payload, you have an indeterminate loading condition where the payload is assuming some of the fairing loads, or vice versa. There is no way to predict the loads in that case, so there's no way to qualify the payload or fairing if that happens.

When the F9 is horizontal, the payload is cantilevered from the PAF. The fairing is cantilevered from its mounting fixture around the upper stage. Most launch providers have a very large piece of GSE that will hold the integrated fairing/payload cantilevered from the mounting face for integration to the launch vehicle if they use horizontal integration.

I can't say categorically that SpaceX does not use the fairing as a lifting point for payload integration, although that would require either that every fairing is designed for the mass and inertia of its specific payload, or that every fairing is designed to take the loads of the heaviest payload F9 is capable of flying, either of which would be surprising as compared to just making some GSE to take the loads. But I will say categorically that the payload never, ever touches the inside of the fairing, as payload designers would find it impossible to definitively calculate those loads and verify against the (nondeterministic) models.

You are in fact wrong. The F9 fairing is radically stronger than those of other vehicles, exactly because it supports the entire mass of the payload after integration and breakover of the enclosed payload assembly.

Start here: https://forum.nasaspaceflight.com/index.php?topic=37727.msg1646197#msg1646197 (https://forum.nasaspaceflight.com/index.php?topic=37727.msg1646197#msg1646197)
and read the linked posts. They do a great job of explaining.

You yelling "NO" three consecutive times does not change reality.
Title: Re: Fairing reuse
Post by: Jim on 05/24/2018 07:11 pm

I can't say categorically that SpaceX does not use the fairing as a lifting point for payload integration, although that would require either that every fairing is designed for the mass and inertia of its specific payload, or that every fairing is designed to take the loads of the heaviest payload F9 is capable of flying,

It does. And the fairing lying on its side is taking the load of the payload because the PAF is supported by the fairing and not GSE.
Title: Re: Fairing reuse
Post by: JamesH65 on 05/25/2018 09:16 am
Plus the truly major savings is in forgoing the need to build out additional production lines to support raised launch rates.  Those added production lines are real killers in both tooling costs and square footage needs.  And if the increased launch rate isn't enough to make full use of the newly added capacity, then you end up with an inefficient investment as well.
True.

The flip side of course is that if BFR is on schedule then there will not be a need to ramp up faring production as BFR will carry those payloads.

In which case this is something of a waste of time.

OTOH if BFR is late this will be a nice cost reduction contingency plan to fall back on (and allow more resources to be diverted to speeding up the BFR roll out).

There are going to be well over a hundred F9 launches before BFR, probably 200! That, at $6M a pop, is between $600M and $1.2B of fairings thrown away. If it costs $600M (minus refurb costs) to get recovery working, I would be very VERY surprised, so this work is almost certainly worth doing.
Title: Re: Fairing reuse
Post by: edzieba on 05/25/2018 02:14 pm
...Obviously it's impossible to say what damage exposure to seawater has done to them so I guess they'll be off to the testing shop to find out...

Preventing seawater damage to composite structures is a well-known technology. I wonder if it'd be cheaper to just build the fairings to tolerate seawater rather than coming up with all the elaborate boat-chasing hardware and procedures. Or are there spaceflight requirements that prevent essentially launching with a boat covering the payload?
The two main techniques for preventing seawater damage to an object, and the only two that are 100% effective, are a) keep the object out of the seawater and b) keep the seawater out of the object.
The fairings need to be porous (vented) to they can be brought from 1ATM or near 0ATM and back without bursting or collapsing, which is at odds with the need to seal them against seawater ingress. Keeping them out of the seawater in the first place is preferable to a complete fairing redesign to avoid internal pockets.
Title: Re: Fairing reuse
Post by: speedevil on 05/25/2018 03:26 pm
The two main techniques for preventing seawater damage to an object, and the only two that are 100% effective, are a) keep the object out of the seawater and b) keep the seawater out of the object.
The fairings need to be porous (vented) to they can be brought from 1ATM or near 0ATM and back without bursting or collapsing, which is at odds with the need to seal them against seawater ingress. Keeping them out of the seawater in the first place is preferable to a complete fairing redesign to avoid internal pockets.

The internal pressure in vacuum is only 14PSI, or somewhere slightly over that due to heating.
14PSI, in the context of a CF honeycomb structure, may be entirely structurally irrelevant and containing it may be less work than venting it.
Title: Re: Fairing reuse
Post by: DistantTemple on 05/25/2018 07:27 pm
The two main techniques for preventing seawater damage to an object, and the only two that are 100% effective, are a) keep the object out of the seawater and b) keep the seawater out of the object.
The fairings need to be porous (vented) to they can be brought from 1ATM or near 0ATM and back without bursting or collapsing, which is at odds with the need to seal them against seawater ingress. Keeping them out of the seawater in the first place is preferable to a complete fairing redesign to avoid internal pockets.

The internal pressure in vacuum is only 14PSI, or somewhere slightly over that due to heating.
14PSI, in the context of a CF honeycomb structure, may be entirely structurally irrelevant and containing it may be less work than venting it.
Do you know if the CF honeycomb is safe in vacuum. Your logic above, alone, is not valid. 14 psi = 10 tonnes/sqm. Which just as convincingly sounds like the sort of force (OK tonnes force is not SI unit) that would expand a honeycomb to destruction!
Title: Re: Fairing reuse
Post by: speedevil on 05/25/2018 07:53 pm
The two main techniques for preventing seawater damage to an object, and the only two that are 100% effective, are a) keep the object out of the seawater and b) keep the seawater out of the object.
The fairings need to be porous (vented) to they can be brought from 1ATM or near 0ATM and back without bursting or collapsing, which is at odds with the need to seal them against seawater ingress. Keeping them out of the seawater in the first place is preferable to a complete fairing redesign to avoid internal pockets.

The internal pressure in vacuum is only 14PSI, or somewhere slightly over that due to heating.
14PSI, in the context of a CF honeycomb structure, may be entirely structurally irrelevant and containing it may be less work than venting it.
Do you know if the CF honeycomb is safe in vacuum. Your logic above, alone, is not valid. 14 psi = 10 tonnes/sqm. Which just as convincingly sounds like the sort of force (OK tonnes force is not SI unit) that would expand a honeycomb to destruction!

14PSI is also 14 pounds per square inch. Or perhaps a couple of pounds per linear inch of aluminium honeycomb edge if that honeycomb has cells around 8mm. It would be quite hard to get a CF/Al joint that bad.

I have made considerably less advanced honeycomb than this, and the delamination strength would have been well over 140, rather than 14 PSI.
It is unclear if the honeycomb/CF they are using is structurally airtight to 14PSI without extra work - it is at least plausible.

If other loads are much larger than 14PSI in the structure, and they likely are, the ability to resist exploding in vacuum may be free.
Title: Re: Fairing reuse
Post by: DistantTemple on 05/25/2018 10:33 pm
thanks Speedevil:
Quote from: speedevil
I have made considerably less advanced honeycomb than this, and the delamination strength would have been well over 140, rather than 14 PSI.
Ok good data. And I guess the exterior composite surface could be easily made waterproof with extra resin, gel-coat etc (I only have v limited boat experience!). However all the sound baffles, which I assume are naturally soft and absorbent, as well as internal equipment cannot be sealed, and would have to be stripped and replaced. Contamination and salt residue would collect behind every item and cable, and damp and salt, would seek ingress at every fastener.
Title: Re: Fairing reuse
Post by: deruch on 05/26/2018 01:03 am
The two main techniques for preventing seawater damage to an object, and the only two that are 100% effective, are a) keep the object out of the seawater and b) keep the seawater out of the object.
The fairings need to be porous (vented) to they can be brought from 1ATM or near 0ATM and back without bursting or collapsing, which is at odds with the need to seal them against seawater ingress. Keeping them out of the seawater in the first place is preferable to a complete fairing redesign to avoid internal pockets.

The internal pressure in vacuum is only 14PSI, or somewhere slightly over that due to heating.
14PSI, in the context of a CF honeycomb structure, may be entirely structurally irrelevant and containing it may be less work than venting it.

How many satellites are designed to experience a sudden, catastrophic depressurization of 14 PSI when you explosively jettison the fairings?  Surviving the shock of fairing jettison is already a S/C design driver.  And that's with fairings that are vented to reduce the pressure differential. 
Title: Re: Fairing reuse
Post by: Swedish chef on 05/26/2018 05:16 am
The two main techniques for preventing seawater damage to an object, and the only two that are 100% effective, are a) keep the object out of the seawater and b) keep the seawater out of the object.

I am wondering, are there any technique that the fairings could be washed clean if they where to be subjected to seawater? I'm thinking of submersion in distilled water until no trace of sodium chloride could be detected? If that is the case one could skip the chase boat and personnel and probably get a even cheaper solution to faring reuse.
Title: Re: Fairing reuse
Post by: john smith 19 on 05/26/2018 06:18 am
The two main techniques for preventing seawater damage to an object, and the only two that are 100% effective, are a) keep the object out of the seawater and b) keep the seawater out of the object.
The fairings need to be porous (vented) to they can be brought from 1ATM or near 0ATM and back without bursting or collapsing, which is at odds with the need to seal them against seawater ingress. Keeping them out of the seawater in the first place is preferable to a complete fairing redesign to avoid internal pockets.

The internal pressure in vacuum is only 14PSI, or somewhere slightly over that due to heating.
14PSI, in the context of a CF honeycomb structure, may be entirely structurally irrelevant and containing it may be less work than venting it.
Do you know if the CF honeycomb is safe in vacuum. Your logic above, alone, is not valid. 14 psi = 10 tonnes/sqm. Which just as convincingly sounds like the sort of force (OK tonnes force is not SI unit) that would expand a honeycomb to destruction!

14PSI is also 14 pounds per square inch. Or perhaps a couple of pounds per linear inch of aluminium honeycomb edge if that honeycomb has cells around 8mm. It would be quite hard to get a CF/Al joint that bad.

I have made considerably less advanced honeycomb than this, and the delamination strength would have been well over 140, rather than 14 PSI.
It is unclear if the honeycomb/CF they are using is structurally airtight to 14PSI without extra work - it is at least plausible.

If other loads are much larger than 14PSI in the structure, and they likely are, the ability to resist exploding in vacuum may be free.
I'm getting the impression you're talking at cross purposes to each other.

One of you seems concerned about the pressure between the inside and outside surfaces of the fairing. The other (it seems) is more concerned about the cells bursting. These are completely different effects.

Vented honeycomb has certainly been made (pin holes in the walls of the cells or little bits "chewed" out of the edges of each end of the wall material) but I'm not sure if air tightness is a design requirement. With a peel strength of 140psi that should certainly resist any internal expansion blowing the end caps off the cells.

The 2 fairing parts do look kind of like boats but boats with no stern. I suspect the it is more a problem of sea water soaking inside the shell and all the stuff attached to it. If the acoustic blankets need to be open cell to be effective at their thickness then sealing them doesn't seem to be an option.

OTOH I expect fairing recovery to be a much simpler task than recovery of the rest of the upper stage.
Title: Re: Fairing reuse
Post by: RDMM2081 on 05/27/2018 06:12 pm
The two main techniques for preventing seawater damage to an object, and the only two that are 100% effective, are a) keep the object out of the seawater and b) keep the seawater out of the object.

I am wondering, are there any technique that the fairings could be washed clean if they where to be subjected to seawater? I'm thinking of submersion in distilled water until no trace of sodium chloride could be detected? If that is the case one could skip the chase boat and personnel and probably get a even cheaper solution to faring reuse.

Not trying to be obtuse, but SpaceX are the actual rocket engineers here and they have obviously decided that immersion and then rinsing is not the path to recovery and reuse of the fairings.  There is no middle ground of designing for immersion, they are designing for dry recovery.  I doubt very much that any of us here are qualified to second guess this decision.
Title: Re: Fairing reuse
Post by: jpo234 on 05/31/2018 07:43 am
From Recticel maakt cruciale onderdelen voor raketbedrijf Elon Musk (https://translate.google.com/translate?sl=auto&tl=en&js=y&prev=_t&hl=de&ie=UTF-8&u=https%3A%2F%2Fwww.tijd.be%2Fondernemen%2Fdefensie-ruimtevaart%2Frecticel-trots-op-ruimtestunt%2F10016572.html&edit-text=)

Quote
The company is already working on a successor for the black panels that it used at the Tesla launch. 'We are working on a hydrophobic version, to keep the pieces afloat when they fall into the sea. Reuse is one of the hobbies of SpaceX. '
Title: Re: Fairing reuse
Post by: deruch on 05/31/2018 03:21 pm
From Recticel maakt cruciale onderdelen voor raketbedrijf Elon Musk (https://translate.google.com/translate?sl=auto&tl=en&js=y&prev=_t&hl=de&ie=UTF-8&u=https%3A%2F%2Fwww.tijd.be%2Fondernemen%2Fdefensie-ruimtevaart%2Frecticel-trots-op-ruimtestunt%2F10016572.html&edit-text=)

Quote
The company is already working on a successor for the black panels that it used at the Tesla launch. 'We are working on a hydrophobic version, to keep the pieces afloat when they fall into the sea. Reuse is one of the hobbies of SpaceX. '

Cool find, thanks. 

Just a note, this company makes the blocks/panels that get fixed on the interior face of the fairing to absorb acoustic vibrations.  Even though it mentions "fall[ing] into the sea," I would be surprised if this was related to plans that would allow actual immersion of the fairings as opposed to protecting them from spray/wetting after they are caught.  Also, due to the fall through the atmosphere as an open halfshell, I wouldn't be surprised to learn that there was enough water getting condensed on the inner surface to potentially be a concern.
Title: Re: Fairing reuse
Post by: dglow on 05/31/2018 07:25 pm
Quote from: SpaceX
Falcon 9 fairing halves deployed their parafoils and splashed down in the Pacific Ocean last week after the launch of Iridium-6/GRACE-FO. Closest half was ~50m from SpaceX’s recovery ship, Mr. Steven.

https://mobile.twitter.com/SpaceX/status/1002268835175518208
Title: Re: Fairing reuse
Post by: deruch on 05/31/2018 07:38 pm
Quote from: SpaceX
Falcon 9 fairing halves deployed their parafoils and splashed down in the Pacific Ocean last week after the launch of Iridium-6/GRACE-FO. Closest half was ~50m from SpaceX’s recovery ship, Mr. Steven.

https://mobile.twitter.com/SpaceX/status/1002268835175518208

Included 3 pics at original resolution.

edit: ninja'd by FST, but my attached pics are the higher resolution ones.  ;)
Title: Re: Fairing reuse
Post by: dglow on 05/31/2018 08:07 pm
Those brown stripes on the second pic... that's a well-toasted marshmallow.
Title: Re: Fairing reuse
Post by: Helodriver on 05/31/2018 08:25 pm
In the image under chute, some damage can be seen to the left side trailing edge.
Title: Re: Fairing reuse
Post by: wannamoonbase on 05/31/2018 08:33 pm
Very close and super cool.  Great pictures.  Video would be amazing.

Do we know for certain if they are trying to steer the fairing to the boat being stationary, or if they have the boat moving and moving toward the most probable location.

Flying to a fixed point with a fairing and para-foil seems possible but not reliable.

In my head I had just assumed that the boat would be moving slowly and just behind a predicted location determined by radar and speed etc.

Edit: my crude hand drawing, sorry.

Title: Re: Fairing reuse
Post by: Nomadd on 05/31/2018 08:36 pm
 Given the tiny possibilties of tiny amounts of contamination that's delayed launches, I can see being hesitant to use fairings that have been immersed in seawater, no matter how well you think you've cleaned them. Seawater has a lot of things besides salt in it and some of them don't just rinse off. Electrical and mechanical problems  from contamination can lurk for years before causing trouble. Even the cleaning of incidental spray if they do manage to net them won't be that easy.
Title: Re: Fairing reuse
Post by: matthewkantar on 05/31/2018 09:09 pm
In the image under chute, some damage can be seen to the left side trailing edge.

I don't see that, could you please circle it for me?
Title: Re: Fairing reuse
Post by: virnin on 05/31/2018 10:10 pm
In the image under chute, some damage can be seen to the left side trailing edge.

I don't see that, could you please circle it for me?

I think the reference was to damage to the chute, not the fairing.  It might be a big enough hole to adversely affect steering the para-foil.
Title: Re: Fairing reuse
Post by: cferreir on 05/31/2018 10:35 pm
Those brown stripes on the second pic... that's a well-toasted marshmallow.

No kidding...Lots of burn marks outside and it looks like inside too. Can that be re-used even if caught dry?? Uggh.
Title: Re: Fairing reuse
Post by: JJB on 05/31/2018 10:45 pm
In the image under chute, some damage can be seen to the left side trailing edge.
Also, in the second shot, one of the lines on the right hand riser is broken.
Title: Re: Fairing reuse
Post by: Swoopert on 05/31/2018 11:41 pm
Yeah, there's a fair bit of damage visible to both parafoils, which really makes how close they got to Mr Steven (in order to get those pre-landing shots) seriously impressive. An extremely resilient design, once they work out the optimum opening sequence to protect them, they'll be on Mr Steven no bother. That many broken lines on a sport canopy and it would be totally unflyable!
Title: Re: Fairing reuse
Post by: woods170 on 06/01/2018 06:36 am
Yeah, there's a fair bit of damage visible to both parafoils, which really makes how close they got to Mr Steven (in order to get those pre-landing shots) seriously impressive. An extremely resilient design, once they work out the optimum opening sequence to protect them, they'll be on Mr Steven no bother. That many broken lines on a sport canopy and it would be totally unflyable!

That's why SpaceX does those landing tests. To work the kinks out of the system. Similar to how it landed many a first stage into the ocean while working the kinks out of that. It is just a matter of time before Mr. Steven actually catches one of those fairing halves.
Title: Re: Fairing reuse
Post by: georgegassaway on 06/01/2018 06:51 am
Those brown stripes on the second pic... that's a well-toasted marshmallow.
I suspect it's streaked char residue from the paint or decals of the Iridium-6 and Grace-FO logos (if that's the half that had the logos).
Title: Re: Fairing reuse
Post by: woods170 on 06/01/2018 09:50 am
Those brown stripes on the second pic... that's a well-toasted marshmallow.
I suspect it's streaked char residue from the paint or decals of the Iridium-6 and Grace-FO logos (if that's the half that had the logos).

Streaks on the fairing half are indeed the charred remains of the Iridium-6 and Grace-FO logo decals. SpaceX uses decals, similar to Arianespace.

The other fairing half has none of those streaks, but does contain the US flag. However, that flag is done the same way as the US flag on the F9 first stage: heat resistant paint.
Title: Re: Fairing reuse
Post by: Semmel on 06/01/2018 10:38 am
Streaks on the fairing half are indeed the charred remains of the Iridium-6 and Grace-FO logo decals. SpaceX uses decals, similar to Arianespace.

The other fairing half has none of those streaks, but does contain the US flag. However, that flag is done the same way as the US flag on the F9 first stage: heat resistant paint.

Well, they need a new logo for the next flight of the fairing anyway..
Title: Re: Fairing reuse
Post by: Raul on 06/01/2018 11:04 am
In the image under chute, some damage can be seen to the left side trailing edge.
Also, in the second shot, one of the lines on the right hand riser is broken.
Note they use a rapid canopy deployment without slider now, perhaps to suppress problems with twisting during deployment -  what happened during Iridium-5 mission. I think something like slider can be seen in last landing photo during TESS mission, to reduce the dynamic impact when opening the parafoil.

It is also looks to be a single-surface parafoil, compare to cells used in common parachutes/paragliders.

Both have greater demands on the strength of the parafoil.
Title: Re: Fairing reuse
Post by: wannamoonbase on 06/01/2018 01:04 pm
Would the new black heat material on the Block 5 legs and interstate protect the fairing halves?
Title: Re: Fairing reuse
Post by: edzieba on 06/01/2018 02:41 pm
It would likely be unnecessary addition of mass. The fairings are so light for their surface area that they are already surviving re-entry with minimal damage form the heat beyond burnt decals.
Title: Re: Fairing reuse
Post by: RDMM2081 on 06/01/2018 04:44 pm
Just a guess, but I think they actually lose the decals on the way up, probably somewhere around maxQ.  Just a guess.

edit: nevermind, the burn patterns are all wrong for that, but leaving the comment here anyway.
Title: Re: Fairing reuse
Post by: freds on 06/01/2018 07:09 pm
Hi Everyone

I haven't been on here in sometime and haven't read each message in the thread. Some thoughts that I have:

1. The satellites need clean room conditions before launch so a contaminated fairing is out. Reminds me of a song and pony dance the Chinese did about their clean room and then someone opened a large door and drove an army truck in....

2. Maybe there could be disposable plastic lining that is simply reapplied before reuse?

3. External customers would probably not go for it on a satellite that is supposed to be in service for ten plus years.

4. But for internal use for the SpaceX consolation with shorter lifespan and control of their own design?
Title: Re: Fairing reuse
Post by: DaveMorgan on 06/01/2018 08:44 pm
Just a guess, but I think they actually lose the decals on the way up, probably somewhere around maxQ.  Just a guess.

edit: nevermind, the burn patterns are all wrong for that, but leaving the comment here anyway.

At around t+120 second  a set of white rings appeared down the rocket body on the IR camera, was it related to that?

Dave
Title: Re: Fairing reuse
Post by: Space Junkie on 06/01/2018 09:36 pm
Have we ever heard a definitive explanation for why they are conducting their fairing recovery tests on the west coast? Given that more launches occur from Florida (including more fairing launches), wouldn't it make more sense to station a boat like Mr. Steven there instead?

Maybe the Iridium launches give them plenty of mass margin to play with whereas many of of the east coast launches do not? Some other reason?

(Apologies if this has been addressed previously.)
Title: Re: Fairing reuse
Post by: deruch on 06/02/2018 07:53 am
Have we ever heard a definitive explanation for why they are conducting their fairing recovery tests on the west coast? Given that more launches occur from Florida (including more fairing launches), wouldn't it make more sense to station a boat like Mr. Steven there instead?

Maybe the Iridium launches give them plenty of mass margin to play with whereas many of of the east coast launches do not? Some other reason?

(Apologies if this has been addressed previously.)

I haven't ever seen anything addressing it.  My guess is that it's because the distance the ship has to travel to get on station for the catch attempt is much shorter for launches out of VAFB which travel south along the coast.  Also, I assume the engineering team working on it is based in Hawthorne, so west coast launches meas they get direct access to the recovered halves/hardware without either having to travel to FL or ship the recovered halves/hardware back across the country.  And while having more launches to test on is a potential benefit, it's probably hard to push design changes through much faster than within a month.  Especially if you first have to figure out what went wrong and then come up with a solution.  So, while the VAFB launch tempo might result in an extra month delay now and then if they just miss the deadline for the next launch, on the whole, it is likely fast enough for development needs.
Title: Re: Fairing reuse
Post by: rsdavis9 on 06/02/2018 10:51 am
Have we ever heard a definitive explanation for why they are conducting their fairing recovery tests on the west coast? Given that more launches occur from Florida (including more fairing launches), wouldn't it make more sense to station a boat like Mr. Steven there instead?

Maybe the Iridium launches give them plenty of mass margin to play with whereas many of of the east coast launches do not? Some other reason?

(Apologies if this has been addressed previously.)

I haven't ever seen anything addressing it.  My guess is that it's because the distance the ship has to travel to get on station for the catch attempt is much shorter for launches out of VAFB which travel south along the coast.  Also, I assume the engineering team working on it is based in Hawthorne, so west coast launches meas they get direct access to the recovered halves/hardware without either having to travel to FL or ship the recovered halves/hardware back across the country.  And while having more launches to test on is a potential benefit, it's probably hard to push design changes through much faster than within a month.  Especially if you first have to figure out what went wrong and then come up with a solution.  So, while the VAFB launch tempo might result in an extra month delay now and then if they just miss the deadline for the next launch, on the whole, it is likely fast enough for development needs.

Plus they still have the recovery hardware on the east coast launches and can watch how it comes down which is 90% of the test.
Title: Re: Fairing reuse
Post by: AUricle on 06/02/2018 11:35 am
Have we ever heard a definitive explanation for why they are conducting their fairing recovery tests on the west coast? Given that more launches occur from Florida (including more fairing launches), wouldn't it make more sense to station a boat like Mr. Steven there instead?

Maybe the Iridium launches give them plenty of mass margin to play with whereas many of of the east coast launches do not? Some other reason?

(Apologies if this has been addressed previously.)

I haven't ever seen anything addressing it.  My guess is that it's because the distance the ship has to travel to get on station for the catch attempt is much shorter for launches out of VAFB which travel south along the coast.  Also, I assume the engineering team working on it is based in Hawthorne, so west coast launches meas they get direct access to the recovered halves/hardware without either having to travel to FL or ship the recovered halves/hardware back across the country.  And while having more launches to test on is a potential benefit, it's probably hard to push design changes through much faster than within a month.  Especially if you first have to figure out what went wrong and then come up with a solution.  So, while the VAFB launch tempo might result in an extra month delay now and then if they just miss the deadline for the next launch, on the whole, it is likely fast enough for development needs.

Plus they still have the recovery hardware on the east coast launches and can watch how it comes down which is 90% of the test.

Thoroughly unresearched guess........sea conditions off the west coast may be more reliable for favorable catch probability?? Rough seas, hurricane season, etc.....on the Atlantic side.
Title: Re: Fairing reuse
Post by: freds on 06/02/2018 03:03 pm
Have we ever heard a definitive explanation for why they are conducting their fairing recovery tests on the west coast? Given that more launches occur from Florida (including more fairing launches), wouldn't it make more sense to station a boat like Mr. Steven there instead?

Maybe the Iridium launches give them plenty of mass margin to play with whereas many of of the east coast launches do not? Some other reason?

(Apologies if this has been addressed previously.)

Well with the StarLink satellite constellation in the pipe line most of those launches would be out of the west coast?
Title: Re: Fairing reuse
Post by: cppetrie on 06/02/2018 03:26 pm
Have we ever heard a definitive explanation for why they are conducting their fairing recovery tests on the west coast? Given that more launches occur from Florida (including more fairing launches), wouldn't it make more sense to station a boat like Mr. Steven there instead?

Maybe the Iridium launches give them plenty of mass margin to play with whereas many of of the east coast launches do not? Some other reason?

(Apologies if this has been addressed previously.)

Well with the StarLink satellite constellation in the pipe line most of those launches would be out of the west coast?
This is often assumed but not necessarily true. A very large portion of the sats will be put in orbits that are accessible from the eastern range. The target orbits are available in the FCC paperwork and have been previously discussed in other threads. I don’t recall the specifics off the top of my head.
Title: Re: Fairing reuse
Post by: deruch on 06/02/2018 03:30 pm
Well with the StarLink satellite constellation in the pipe line most of those launches would be out of the west coast?
No, East Coast.  Most of the StarLink constellation has an unexpectedly low inclination.  3200 of the 4425 satellites are in orbits inclined either 53 or 53.8 degrees--including all of the "initial deployment".
Title: Re: Fairing reuse
Post by: cppetrie on 06/02/2018 03:51 pm
Well with the StarLink satellite constellation in the pipe line most of those launches would be out of the west coast?
No, East Coast.  Most of the StarLink constellation has an unexpectedly low inclination.  3200 of the 4425 satellites are in orbits inclined either 53 or 53.8 degrees--including all of the "initial deployment".
Those inclinations cover something like 90+% of the world’s population. The other higher inclination orbits are there to provide the constellation with complete global coverage but far fewer are needed in those high inclination orbits to provide the coverage and capacity required over the polar and sub-polar regions.

Edit: we should probably get back on topic though.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 06/04/2018 12:47 pm
Quote
It looks like GO Pursuit bagged her catch overnight and is heading back to Port Canaveral. She was going 8.4 kn at 7:15 am this morning heading west. #SpaceXFleet

https://twitter.com/julia_bergeron/status/1003618232975220737

From screenshot attached to tweet appears to be MarineTraffic.com data (won't paste screenshot here due to MarineTraffic use restrictions).
Title: Re: Fairing reuse
Post by: jpo234 on 06/05/2018 10:13 am
https://twitter.com/ang3lwtf/status/1003852615052980224

Quote
Angel Garcia
‏ @ang3lwtf

@elonmusk I may not be an engineer but why not make Mr.Steven's arms wider so it can have a bigger net? It's finally time to catch some fairings. 😏😏

https://twitter.com/elonmusk/status/1003916871693791232

Quote
Answer to @ang3lwtf

Yup, we are extending the net area by a factor of 4
Title: Re: Fairing reuse
Post by: drzerg on 06/05/2018 12:25 pm
this immediately pops in my mind

https://imgur.com/oIWMyAY

this thing could be as big as practically viable or could be expandable. also addition of powerful winch could add more precision to positioning of the net forward and backward in align to ship.
Title: Re: Fairing reuse
Post by: Robotbeat on 06/06/2018 03:28 am
Just make bigger arms. Steel is cheap, and SpaceX has good welders.
Title: Re: Fairing reuse
Post by: deruch on 06/06/2018 06:10 pm
https://twitter.com/ang3lwtf/status/1003852615052980224

Quote
Angel Garcia
‏ @ang3lwtf

@elonmusk I may not be an engineer but why not make Mr.Steven's arms wider so it can have a bigger net? It's finally time to catch some fairings. 😏😏

https://twitter.com/elonmusk/status/1003916871693791232

Quote
Answer to @ang3lwtf

Yup, we are extending the net area by a factor of 4

This and the following discussion about how it may be implemented fits better in the Mr. Steven Thread (SpaceX facilities and fleets section) where it is also being discussed.

https://forum.nasaspaceflight.com/index.php?topic=45083.0
Title: Re: Fairing reuse
Post by: RocketLover0119 on 06/06/2018 08:47 pm
Holy moly, 4 fairing halves spied in Port L.A!

Teslarati article- https://www.teslarati.com/spacex-bfr-factory-four-falcon-9-fairing-halves-spied/
Title: Re: Fairing reuse
Post by: Raul on 06/06/2018 09:18 pm
Teslarati article- https://www.teslarati.com/spacex-bfr-factory-four-falcon-9-fairing-halves-spied/

Pictures of Berth 240 from the article:
Quote
In an unexpected turn of events, Teslarati photographer Pauline Acalin came across a remarkable scene in Port of Los Angeles – four flight-proven Falcon 9 fairing halves temporarily stored on a plot of land soon to become SpaceX’s dedicated BFR factory.
While it’s difficult to guess exactly which fairing half is which, it appears that the halves from PAZ, Iridium-5, and Iridium-6 are present and accounted for.
Title: Re: Fairing reuse
Post by: Semmel on 06/07/2018 06:32 am
Holy moly, 4 fairing halves spied in Port L.A!

Teslarati article- https://www.teslarati.com/spacex-bfr-factory-four-falcon-9-fairing-halves-spied/

Man that place looks disgusting! I hope the fairings dont catch any of that infectious rust and decomposition of the buildings.
Title: Re: Fairing reuse
Post by: woods170 on 06/07/2018 07:06 am
Holy moly, 4 fairing halves spied in Port L.A!

Teslarati article- https://www.teslarati.com/spacex-bfr-factory-four-falcon-9-fairing-halves-spied/

Man that place looks disgusting! I hope the fairings dont catch any of that infectious rust and decomposition of the buildings.

Why not? The fairings are going to be scrapped anyway. Just like the buildings.
Title: Re: Fairing reuse
Post by: Semmel on 06/07/2018 08:01 am
Holy moly, 4 fairing halves spied in Port L.A!

Teslarati article- https://www.teslarati.com/spacex-bfr-factory-four-falcon-9-fairing-halves-spied/

Man that place looks disgusting! I hope the fairings dont catch any of that infectious rust and decomposition of the buildings.

Why not? The fairings are going to be scrapped anyway. Just like the buildings.

If they are scrapped, why keep them in the first place?
Title: Re: Fairing reuse
Post by: jpo234 on 06/07/2018 08:29 am
Holy moly, 4 fairing halves spied in Port L.A!

Teslarati article- https://www.teslarati.com/spacex-bfr-factory-four-falcon-9-fairing-halves-spied/

Man that place looks disgusting! I hope the fairings dont catch any of that infectious rust and decomposition of the buildings.

Why not? The fairings are going to be scrapped anyway. Just like the buildings.

If they are scrapped, why keep them in the first place?

Sell them to a collector or somebody who wants an unusual swimming pool?
Title: Re: Fairing reuse
Post by: vanoord on 06/07/2018 09:36 am
Holy moly, 4 fairing halves spied in Port L.A!

Teslarati article- https://www.teslarati.com/spacex-bfr-factory-four-falcon-9-fairing-halves-spied/

Man that place looks disgusting! I hope the fairings dont catch any of that infectious rust and decomposition of the buildings.

Why not? The fairings are going to be scrapped anyway. Just like the buildings.

If they are scrapped, why keep them in the first place?

They may be used for drop testing?
Title: Re: Fairing reuse
Post by: su27k on 06/07/2018 11:35 am
If they are scrapped, why keep them in the first place?

Because they can't just throw away hardware due to ITAR? Also SpaceX is kind of a packrat, they keep a lot of junk around, including old Falcon 1 tank.
Title: Re: Fairing reuse
Post by: woods170 on 06/07/2018 12:19 pm
Holy moly, 4 fairing halves spied in Port L.A!

Teslarati article- https://www.teslarati.com/spacex-bfr-factory-four-falcon-9-fairing-halves-spied/

Man that place looks disgusting! I hope the fairings dont catch any of that infectious rust and decomposition of the buildings.

Why not? The fairings are going to be scrapped anyway. Just like the buildings.

If they are scrapped, why keep them in the first place?

Temporary storage until shipping for scrapping.
Title: Re: Fairing reuse
Post by: DistantTemple on 06/07/2018 05:38 pm
Quote from: woods170
Just like the buildings
5 out of 6 of the buildings are protected historic buildings.  .... I haven't checked if that one is the one the fairings are under/in front of.

SX could roll out amazing momentous, bar furniture etc with used bits of rockets... They could grace SX customer foyers.
Title: Re: Fairing reuse
Post by: rsdavis9 on 06/07/2018 07:33 pm
Build a tiny house with one...
Title: Re: Fairing reuse
Post by: wannamoonbase on 06/07/2018 07:58 pm
Build a tiny house with one...

Not that tiny.  I’ve measured, 1 fairing half is about the size of my apartment.

Hanging onto things is cheap and easy if you have available space. Just ask any farmer. 
Title: Re: Fairing reuse
Post by: aero on 06/07/2018 08:19 pm
Paint them green and stick them upside down under bridges for homeless shelters, then take the tax deduction!
Title: Re: Fairing reuse
Post by: CuddlyRocket on 06/07/2018 10:16 pm
Hanging onto things is cheap and easy if you have available space. Just ask any farmer. 

And if so, they should probably hang on to them - you never know when they might unexpectedly come in useful. Most of us have had that feeling when you've got rid of something (or deleted it) and then suddenly found a use for it!

Or perhaps they're running tests on long-term weathering or other ageing? After all, fairings up to now have been used once shortly after manufacture, but if you're going to re-use them they might be around for years!
Title: Re: Fairing reuse
Post by: Ludus on 06/07/2018 10:37 pm
So what’s the next step after they successfully capture one?

How do they extend the process to getting them both?

Program one to loiter around going in circles more while they catch the first, then very rapidly lower it to the deck and shove it forward off the net while the ship is repositioning at full speed to catch the second one? That would look pretty dramatic.
Title: Re: Fairing reuse
Post by: wannamoonbase on 06/07/2018 10:39 pm
So what’s the next step after they successfully capture one?

How do they extend the process to getting them both?

Program one to loiter around going in circles more while they catch the first, then very rapidly lower it to the deck and shove it forward while the ship is repositioning to catch the second one? That would look pretty dramatic.

I’ve always assumed a second boat.
Title: Re: Fairing reuse
Post by: John Alan on 06/07/2018 10:40 pm
So what’s the next step after they successfully capture one?

How do they extend the process to getting them both?

Program one to loiter around going in circles more while they catch the first, then very rapidly lower it to the deck and shove it forward while the ship is repositioning to catch the second one? That would look pretty dramatic.

Hire a 2nd, 3rd, and 4th boat on long term leases and complete you fleet on both coasts...  ;)
Title: Re: Fairing reuse
Post by: Ludus on 06/07/2018 10:46 pm
So what’s the next step after they successfully capture one?

How do they extend the process to getting them both?

Program one to loiter around going in circles more while they catch the first, then very rapidly lower it to the deck and shove it forward while the ship is repositioning to catch the second one? That would look pretty dramatic.

I’ve always assumed a second boat.

That’s cheating.
Title: Re: Fairing reuse
Post by: EnigmaSCADA on 07/06/2018 03:57 pm
Has there been any reasoned speculation or maybe even an explanation from spaceX (not that they owe one) for there not being video (live or recorded) of fairing recovery attempts?

One of the things that currently makes SpaceX undisputably the most interesting launch provider (yes, undisputably, I don't think I could seriously entertain a counter argument) is their openness, willingness, and daring to attempt difficult things with high failure probabilities in a public manner, unafraid of embarrassment and criticism.

I suppose it may not be worth the FTE time or money to setup the infrastructure for a live feed from the ship (yet, if I had to bet, I'd be inclined to guess they do have this) but surely at a minimum they have engineering cameras on board ship or possibly even the fairing that are recording these attempts, right?

I realize it's easy for me to suggest from my desk chair and it's quite a luxury what they already display to the interested public under no obligation.... But I want to see it happening! Even the failures where the Mr. Steven crew are scratching their heads thinking "hmmm, the fairing should have been here a minute ago".
Title: Re: Fairing reuse
Post by: Cheapchips on 07/06/2018 09:35 pm
Has there been any reasoned speculation or maybe even an explanation from spaceX (not that they owe one) for there not being video (live or recorded) of fairing recovery attempts?

One of the things that currently makes SpaceX undisputably the most interesting launch provider (yes, undisputably, I don't think I could seriously entertain a counter argument) is their openness, willingness, and daring to attempt difficult things with high failure probabilities in a public manner, unafraid of embarrassment and criticism.

I suppose it may not be worth the FTE time or money to setup the infrastructure for a live feed from the ship (yet, if I had to bet, I'd be inclined to guess they do have this) but surely at a minimum they have engineering cameras on board ship or possibly even the fairing that are recording these attempts, right?

I realize it's easy for me to suggest from my desk chair and it's quite a luxury what they already display to the interested public under no obligation.... But I want to see it happening! Even the failures where the Mr. Steven crew are scratching their heads thinking "hmmm, the fairing should have been here a minute ago".

Speculation on my part, but they probably want to avoid the "SpaceX fails to capture fairing again", "SpaceX fairing crash lands into the sea" headlines.
Title: Re: Fairing reuse
Post by: Lar on 07/07/2018 02:10 pm
Speculation on my part, but they probably want to avoid the "SpaceX fails to capture fairing again", "SpaceX fairing crash lands into the sea" headlines.
Yep. Concern trolls are everywhere.
Title: Re: Fairing reuse
Post by: speedevil on 07/07/2018 08:05 pm
Speculation on my part, but they probably want to avoid the "SpaceX fails to capture fairing again", "SpaceX fairing crash lands into the sea" headlines.
Has there ever been any of these headlines, such as they are, that did not originate from data SpaceX provided?
Simply not saying anything about testing would fix that.
Title: Re: Fairing reuse
Post by: testguy on 07/07/2018 09:01 pm
Speculation on my part, but they probably want to avoid the "SpaceX fails to capture fairing again", "SpaceX fairing crash lands into the sea" headlines.
Has there ever been any of these headlines, such as they are, that did not originate from data SpaceX provided?
Simply not saying anything about testing would fix that.

Zuma gets close to ringing that bell.   Please let’s not get into another long discussion about Zuma..
Title: Re: Fairing reuse
Post by: wannamoonbase on 07/07/2018 10:36 pm
Speculation on my part, but they probably want to avoid the "SpaceX fails to capture fairing again", "SpaceX fairing crash lands into the sea" headlines.
Has there ever been any of these headlines, such as they are, that did not originate from data SpaceX provided?
Simply not saying anything about testing would fix that.

EM likes positive press and goes to war against things he doesn’t like.  Why show the slow trickle of development then eventual success, when surely, some stories will say ‘They finally succeeded.’  When it works then I think we’ll see videos.
Title: Re: Fairing reuse
Post by: johnfwhitesell on 07/08/2018 03:12 am
Why are fairings so expensive anyways?
Title: Re: Fairing reuse
Post by: Comga on 07/08/2018 04:02 am
Why are fairings so expensive anyways?

Do you really need to ask that?
Come on!
Giant, hollow, light-weight, composite, acoustic absorbing, supersonic, aerospace structures that withstand substantial acceleration and aerodynamic loads before faultlessly releasing and falling away?
At $6M SpaceX's fairings are probably a bargain.
Title: Re: Fairing reuse
Post by: woods170 on 07/08/2018 01:38 pm
Why are fairings so expensive anyways?

Do you really need to ask that?
Cone on!
Giant, hollow, light-weight, composite, acoustic absorbing, supersonic, aerospace structures that withstand substantial acceleration and aerodynamic loads before faultlessly releasing and falling away?
At $6M SpaceX's fairings are probably a bargain.

The manufacturing process of fairings is very much "hands-on". In other words: very labor intensive and therefore expensive.
Title: Re: Fairing reuse
Post by: john smith 19 on 07/08/2018 01:54 pm
Speculation on my part, but they probably want to avoid the "SpaceX fails to capture fairing again", "SpaceX fairing crash lands into the sea" headlines.
Yep. Concern trolls are everywhere.
Given that there is significant potential for cost reduction, and the speeds and altitudes not far out of what SX have already demonstrated it seems very unlikely that SX will abandon attempts at fairing recovery and reuse.

As others have noted SX fairings appear (are?) substantially more heavily built than competitors. This creates a technology barrier that their competitors cannot climb without substantial redesign, while continuing to lower SX'x costs.

How long it takes for SX to demonstrate recovery (and later reuse) and, just as importantly, over what envelope of missions can it be done is anybodies guess. Personally I think they will have recovered a complete fairing by the end of 2018. 

OTOH we know they like to either retire "first of a kind" hardware or subject it to extended inspection before reuse.  So fairing reuse would be 6-12 months later IMHO.
Title: Re: Fairing reuse
Post by: deruch on 07/08/2018 11:55 pm
Speculation on my part, but they probably want to avoid the "SpaceX fails to capture fairing again", "SpaceX fairing crash lands into the sea" headlines.
Has there ever been any of these headlines, such as they are, that did not originate from data SpaceX provided?

No.  The industry press, which might report on these activities even in the absence of SpaceX provided material/data, understands and reports with proper context regardless of the source/data/images.  It's when the "general" media start reporting on the flashy stuff just to get views/clicks that we get the real crap headlines/stories.  And they only ever get clued into it because SpaceX puts out a flashy/cool video.

Sort of similar to the effect of "Those who know don't talk.  Those who talk don't know."
Title: Re: Fairing reuse
Post by: YEGLego on 07/09/2018 01:18 pm
https://www.teslarati.com/spacex-mr-steven-upgraded-arm-installed-catch-fairing/

Teslarati article showing one of Mr. Steven's new arms installed, as well as an unknown inflatable raft nearby.
Title: Re: Fairing reuse
Post by: venir on 07/11/2018 04:35 pm
Teslarati reporting that arm upgrade on Mr. Steven is complete. Just waiting on new ~40,000 sq ft net.

https://www.teslarati.com/spacex-mr-steven-arm-upgrade-complete-quadruple-size-net/
Title: Re: Fairing reuse
Post by: biosehnsucht on 07/11/2018 09:34 pm
Are the new arms permanently fixed in place, and a potential hazard to other boats when coming and going in the narrower channel areas? Or can they still be folded/swung into the footprint of the boat?

Feels like it needs some orange flags hanging off the tips and WIDE LOAD banners ... :D
Title: Re: Fairing reuse
Post by: whitelancer64 on 07/11/2018 10:38 pm
Are the new arms permanently fixed in place, and a potential hazard to other boats when coming and going in the narrower channel areas? Or can they still be folded/swung into the footprint of the boat?

Feels like it needs some orange flags hanging off the tips and WIDE LOAD banners ... :D

Elon tweeted that they are retractable.

https://twitter.com/elonmusk/status/1017053826640048128
Title: Re: Fairing reuse
Post by: meekGee on 07/11/2018 11:16 pm
He went there!

(Trampoline)

-----
ABCD: Always Be Counting Down

Title: Re: Fairing reuse
Post by: deruch on 07/12/2018 09:47 am
Teslarati reporting that arm upgrade on Mr. Steven is complete. Just waiting on new ~40,000 sq ft net.

https://www.teslarati.com/spacex-mr-steven-arm-upgrade-complete-quadruple-size-net/

Comments and posts that are talking about the ship and any modifications being made to it belong in the Mr. Steven FSV Thread: https://forum.nasaspaceflight.com/index.php?topic=45083.0 

This thread is about SpaceX's general approach to fairing recovery/reuse and their testing results.  Now that Mr. Steven has its own thread any discussion of ship specific information should be done there.  That way we're not getting parallel conversations about the same information.
Title: Re: Fairing reuse
Post by: wannamoonbase on 07/13/2018 07:23 pm
The pictures of the new net deployed are incredible.  Can't wait.

It will be very interesting to see if and when we see 2 ships and fairings being reflown.

End of this year is coming quick but maybe there is an outside shot at that.
Title: Re: Fairing reuse
Post by: docmordrid on 07/13/2018 08:05 pm
https://twitter.com/SpaceX/status/1017807493311811584?s=19

SpaceX ✔ @SpaceX
 Mr. Steven now with more net. SpaceXs fairing recovery vessel has been fitted with a 4x larger net ahead of its next recovery attempt targeted for later this month. http://instagram.com/p/BlLYeNnFZNA/ (http://"http://instagram.com/p/BlLYeNnFZNA/")
12:26 PM - Jul 13, 2018
|
https://twitter.com/ShorealoneFilms/status/1017807808169795584?s=19

Matt Hartman @ShorealoneFilms
yup. i was there

Title: Re: Fairing reuse
Post by: john smith 19 on 07/15/2018 07:37 am
The pictures of the new net deployed are incredible.  Can't wait.

It will be very interesting to see if and when we see 2 ships and fairings being reflown.

End of this year is coming quick but maybe there is an outside shot at that.
Launch cadence suggests they will have plenty of chances to get it right. There are at least 2 FH launches scheduled before 1st of Jan 2019
Title: Re: Fairing reuse
Post by: Comga on 07/16/2018 05:48 am
The pictures of the new net deployed are incredible.  Can't wait.

It will be very interesting to see if and when we see 2 ships and fairings being reflown.

End of this year is coming quick but maybe there is an outside shot at that.

Launch cadence suggests they will have plenty of chances to get it right. There are at least 2 FH launches scheduled before 1st of Jan 2019

I think you missed the point.
FH is not what he is talking about.
I think wannamoonbase means two fairing halves from any Falcon launch being recovered, which takes 2 ships, and then be reflown on a single flight.
edit: But you are right that they will have plenty of chances
Title: Re: Fairing reuse
Post by: aero on 07/16/2018 04:15 pm
If one half of the fairing loitered at altitude for as long as possible while the other half descended as quickly as practical, then after catching the quickly descending fairing half, would there be enough time to lower the net, stow the first half fairing and raise the net to catch the second half fairing?
Title: Re: Fairing reuse
Post by: wannamoonbase on 07/16/2018 07:24 pm
If one half of the fairing loitered at altitude for as long as possible while the other half descended as quickly as practical, then after catching the quickly descending fairing half, would there be enough time to lower the net, stow the first half fairing and raise the net to catch the second half fairing?

Have to disagree, that's a gamble and wrestling something as large a fairing on a fast schedule would be ripe with safety problems.

Buy a second boat and install a second net.
Title: Re: Fairing reuse
Post by: wannamoonbase on 07/16/2018 07:26 pm
The pictures of the new net deployed are incredible.  Can't wait.

It will be very interesting to see if and when we see 2 ships and fairings being reflown.

End of this year is coming quick but maybe there is an outside shot at that.

Launch cadence suggests they will have plenty of chances to get it right. There are at least 2 FH launches scheduled before 1st of Jan 2019

I think you missed the point.
FH is not what he is talking about.
I think wannamoonbase means two fairing halves from any Falcon launch being recovered, which takes 2 ships, and then be reflown on a single flight.
edit: But you are right that they will have plenty of chances

Correct, I meant recovering a full fairing and reflying it.

I agree they have plenty of opportunities to try.  But they'll need to add a second west coast and 2 east coast vessels.
Title: Re: Fairing reuse
Post by: JamesH65 on 07/17/2018 11:06 am
Just have two nets. First fairing lands, drop the net towards the deck (big pads on deck, could go all the way down), 'roll' a new net over the top. As long as the first net can drop enough to give clearance for the second, it's then just a matter of unloading at your leisure.
Title: Re: Fairing reuse
Post by: woods170 on 07/17/2018 11:18 am
Just have two nets. First fairing lands, drop the net towards the deck (big pads on deck, could go all the way down), 'roll' a new net over the top. As long as the first net can drop enough to give clearance for the second, it's then just a matter of unloading at your leisure.


I think you seriously underestimate the amount of time to hoist a second net in place.

Once catching a fairing is proven you will find that a second fairing-catcher ship will be commissioned real soon.
Each fairing-catcher ship will, per mission, catch one fairing half, at best.
Title: Re: Fairing reuse
Post by: Robotbeat on 07/17/2018 12:30 pm
They could also put a high tension rope in the middle of the current net once they get really good at catching to separate the net into two halves.

But it is possible to hoist a new net in a few minutes if designed properly with pulleys. That's enough time separation.
Title: Re: Fairing reuse
Post by: JamesH65 on 07/17/2018 01:12 pm
Just have two nets. First fairing lands, drop the net towards the deck (big pads on deck, could go all the way down), 'roll' a new net over the top. As long as the first net can drop enough to give clearance for the second, it's then just a matter of unloading at your leisure.


I think you seriously underestimate the amount of time to hoist a second net in place.

Once catching a fairing is proven you will find that a second fairing-catcher ship will be commissioned real soon.
Each fairing-catcher ship will, per mission, catch one fairing half, at best.

They will need 4, two on each coast. As long as flight rate is OK that might be cost effective, but remember, they cannot really do anything else between flights with all that hardware bolted on, so once modified that's all they are good for.

With the right deploying equipment, I see no reason why pulling a new net over couldn't be done in a couple of minutes. All down to how fast you can do it.

Edit: Although at 'only' $10-12M each, plus lets say $1M for the arms, plus whatever running costs are incurred, probably not too much of a hit to have 4.
Title: Re: Fairing reuse
Post by: speedevil on 07/17/2018 01:27 pm
They will need 4, two on each coast. As long as flight rate is OK that might be cost effective, but remember, they cannot really do anything else between flights with all that hardware bolted on, so once modified that's all they are good for.
Mr Steven is one of a class of quite fast vessels, they can in principle be repositioned from one coast to the other in a little over a week.
Which is at least another option.
Title: Re: Fairing reuse
Post by: wannamoonbase on 07/17/2018 01:29 pm
Edit: Although at 'only' $10-12M each, plus lets say $1M for the arms, plus whatever running costs are incurred, probably not too much of a hit to have 4.

Is that the price of the ship new?  Elon likes buying used equipment and re-purposing.

The benefits of fairing recovery likely wouldn't work at a low flight rate, but at 24+ flights a year it seems to make sense.

If, Starlink becomes a real thing and they need to launch a few hundred F9's to LEO then it really adds up. 

Title: Re: Fairing reuse
Post by: niwax on 07/17/2018 02:13 pm
Edit: Although at 'only' $10-12M each, plus lets say $1M for the arms, plus whatever running costs are incurred, probably not too much of a hit to have 4.

Is that the price of the ship new?  Elon likes buying used equipment and re-purposing.

I don't think ships depreciate that much, it's likely more about quick availability.

Would a ship on the west coast be that necessary? They have only had a handful of flights from there, and since they own a large number of their launches with Starlink they could schedule to launch from the west coast in bulk and reposition the ships.
Title: Re: Fairing reuse
Post by: JamesH65 on 07/17/2018 07:41 pm
Edit: Although at 'only' $10-12M each, plus lets say $1M for the arms, plus whatever running costs are incurred, probably not too much of a hit to have 4.

Is that the price of the ship new?  Elon likes buying used equipment and re-purposing.

The benefits of fairing recovery likely wouldn't work at a low flight rate, but at 24+ flights a year it seems to make sense.

If, Starlink becomes a real thing and they need to launch a few hundred F9's to LEO then it really adds up.

Closest price I could find to a similar vessel (albeit a slower one, seems like Mr Steven is quite an unusual craft), not sure if it was new or not. I think the construction cost was $12M.
Title: Re: Fairing reuse
Post by: RobLynn on 07/17/2018 10:23 pm
Ships are cheap to build, and a stripped down ship with minimal accommodation that has no other function than to go fast will be even cheaper.

Given the tiny variation in mass that the ship will have in use a small water-line area twin hull (SWATH, effectively submersed pontoons with thin struts extending up through water surface) would likely be best - fast, very stable, insensitive to waves.
https://en.wikipedia.org/wiki/Small-waterplane-area_twin_hull

Being able to tilt the net over by raising or lowering the arms would also seem like a really useful design feature to have to increase the effective target area.
 
Title: Re: Fairing reuse
Post by: woods170 on 07/18/2018 08:13 am
They could also put a high tension rope in the middle of the current net once they get really good at catching to separate the net into two halves.

But it is possible to hoist a new net in a few minutes if designed properly with pulleys. That's enough time separation.

No, it isn't. Both fairing halves are coming down in the same flight profile. They are hitting the water less than half a minute apart. And the lateral separation upon splash-down is larger than Mr. Steven can cover in that time, due to anti-collision considerations.
Title: Re: Fairing reuse
Post by: JamesH65 on 07/18/2018 09:31 am
They could also put a high tension rope in the middle of the current net once they get really good at catching to separate the net into two halves.

But it is possible to hoist a new net in a few minutes if designed properly with pulleys. That's enough time separation.

No, it isn't. Both fairing halves are coming down in the same flight profile. They are hitting the water less than half a minute apart. And the lateral separation upon splash-down is larger than Mr. Steven can cover in that time, due to anti-collision considerations.

Are they? I didnt think we had that information? Surely it depnds on when you open the chute, and how big it is? Open later, with a smaller chute, you could increase the time separation. By how much? Who knows?

But anyway, since I reckon the costs of new ships to chase is only about two fairings sets, it probably easier and fairly cheap just to run multiple ships. Or maybe one really big one.
Title: Re: Fairing reuse
Post by: deruch on 07/18/2018 12:29 pm
IMO, if SpaceX was able to get multi-minute delays on fairing touchdowns by just adjusting the parachutes and timings, then they would have caught a fairing already.  The ability to fly a "delayed drop" fairing so that it splashes down close enough to the original to allow catching it with the same vessel requires the same tech to be able to drop one in a very small dropzone.  If they could control them so precisely, they would have already caught one or at least not needed the arm/net expansion.

Remember that positioning the ship is about more than just getting to spot X by a certain time.  To have the best chance of catching the fairing they will need to be moving as well.  So, they'll do catch attempts like flying a bombing run.  Get the ship to a staging point by the time the fairing is at a certain altitude and flying a set direction (likely into the wind).  Then motor forward underneath, slipping sideways as needed, to eventually catch it.  To lower the net and manhandle the fairing into a safe stowage position on deck while also traveling at high speed to preposition the ship for the second run in the short amount of time potentially available is a lot to ask.  Personally, I'm convinced they'll need a second ship in order to catch both fairings from a single launch.
Title: Re: Fairing reuse
Post by: JamesH65 on 07/18/2018 01:14 pm
IMO, if SpaceX was able to get multi-minute delays on fairing touchdowns by just adjusting the parachutes and timings, then they would have caught a fairing already.  The ability to fly a "delayed drop" fairing so that it splashes down close enough to the original to allow catching it with the same vessel requires the same tech to be able to drop one in a very small dropzone.  If they could control them so precisely, they would have already caught one or at least not needed the arm/net expansion.

Not sure that makes sense. Landing point is irrelevent to the height of deploy (excluding change in cross range whicih is irrelevent). Chute size might make a difference, in that going larger means a lower vertical descent speed. However, these sort of chutes you can trim - trading forward speed with descent rate.

Remember that positioning the ship is about more than just getting to spot X by a certain time.  To have the best chance of catching the fairing they will need to be moving as well.  So, they'll do catch attempts like flying a bombing run.  Get the ship to a staging point by the time the fairing is at a certain altitude and flying a set direction (likely into the wind).  Then motor forward underneath, slipping sideways as needed, to eventually catch it.  To lower the net and manhandle the fairing into a safe stowage position on deck while also traveling at high speed to preposition the ship for the second run in the short amount of time potentially available is a lot to ask.  Personally, I'm convinced they'll need a second ship in order to catch both fairings from a single launch.

Not likely in to the wind. Definitely in to the wind. I don't think the actual process of catching is doubt.

So I think it would be possible to catch both with the same boat, but having looked at the costings of boats vs fairings, it's probably not worth it. Just buy another boat.
Title: Re: Fairing reuse
Post by: Dave G on 07/22/2018 12:29 pm
Any news on the fairing recovery for today's Telesat launch?

According to this article:
https://www.nasaspaceflight.com/2018/07/spacex-falcon-9-telstar-19v-launch/
Quote
While SpaceX does not have a dedicated East Coast recovery ship, and therefore cannot catch the fairing before it hits the water, the company should be able to guide the fairing halves to a soft splashdown and then fish them out of the water.
Title: Re: Fairing reuse
Post by: deruch on 07/22/2018 01:20 pm
Any news on the fairing recovery for today's Telesat launch?

According to this article:
https://www.nasaspaceflight.com/2018/07/spacex-falcon-9-telstar-19v-launch/
Quote
While SpaceX does not have a dedicated East Coast recovery ship, and therefore cannot catch the fairing before it hits the water, the company should be able to guide the fairing halves to a soft splashdown and then fish them out of the water.

They've done the same on at least one prior launch using one of the east coast GO vessels.  If nothing else, it at least gives them some more practice with the controlled/guided descent portion of the fairing recovery attempts.  The only costs being the hardware on the fairings and the operations expenses for sending the extra ship out.
Title: Re: Fairing reuse
Post by: wannamoonbase on 07/22/2018 02:41 pm
Any news on the fairing recovery for today's Telesat launch?

According to this article:
https://www.nasaspaceflight.com/2018/07/spacex-falcon-9-telstar-19v-launch/
Quote
While SpaceX does not have a dedicated East Coast recovery ship, and therefore cannot catch the fairing before it hits the water, the company should be able to guide the fairing halves to a soft splashdown and then fish them out of the water.

They've done the same on at least one prior launch using one of the east coast GO vessels.  If nothing else, it at least gives them some more practice with the controlled/guided descent portion of the fairing recovery attempts.  The only costs being the hardware on the fairings and the operations expenses for sending the extra ship out.

I’ve been wondering about additional testing.  Like their testing with the Block 3&4 cores, where they were pushing the envelop and finding out what they are capable doing, gathering data, flinging out if they can predictably fly them to a point.  Lots of reasons to keep testing.

All positive indications, bring on Mr. Steven’s attempt on Wednesday.
Title: Re: Fairing reuse
Post by: Dave G on 07/22/2018 11:10 pm
Any news on the fairing recovery for today's Telesat launch?

According to this article:
https://www.nasaspaceflight.com/2018/07/spacex-falcon-9-telstar-19v-launch/
Quote
While SpaceX does not have a dedicated East Coast recovery ship, and therefore cannot catch the fairing before it hits the water, the company should be able to guide the fairing halves to a soft splashdown and then fish them out of the water.

They've done the same on at least one prior launch using one of the east coast GO vessels.  If nothing else, it at least gives them some more practice with the controlled/guided descent portion of the fairing recovery attempts...

Also, if they can fish these 2 fairings out of the ocean, they'll probably want to thoroughly inspect them to find out how they can further optimize the design.

It's too bad news outlets don't report more about SpaceX's steps toward fairing reuse.  They all still seem to be focused on first stage landings.  From my point of view, first stage reuse is already "been there, done that".

Fairing reuse is the next big thing SpaceX is working on.  Last I heard, each fairing costs around $5 million.  The fairing is also the next largest item after the first stage.

Title: Re: Fairing reuse
Post by: Coastal Ron on 07/22/2018 11:21 pm
It's too bad news outlets don't report more about SpaceX's steps toward fairing reuse.

It's difficult to report about something that doesn't have images or video to use in a story, and it's still just an experiment. That said, when Mr. Steven catches one I think the press will be all over it.

Quote
They all still seem to be focused on first stage landings.  From my point of view, first stage reuse is already "been there, done that".

Just a reminder that up until this latest launch, all flights were for experiments. The Telstar 19 satellite flew on what should be a production Block 5 Falcon 9 that should be able to demonstrate "normal" reusability - which has not been demonstrated yet.

We're at least two more flights of the 1st stage from Telstar 19 before we can conclude that first stage reuse is already "been there, done that"...

My $0.02
Title: Re: Fairing reuse
Post by: wannamoonbase on 07/23/2018 12:38 am
It's too bad news outlets don't report more about SpaceX's steps toward fairing reuse.

It's difficult to report about something that doesn't have images or video to use in a story, and it's still just an experiment. That said, when Mr. Steven catches one I think the press will be all over it.

Quote
They all still seem to be focused on first stage landings.  From my point of view, first stage reuse is already "been there, done that".

Just a reminder that up until this latest launch, all flights were for experiments. The Telstar 19 satellite flew on what should be a production Block 5 Falcon 9 that should be able to demonstrate "normal" reusability - which has not been demonstrated yet.

We're at least two more flights of the 1st stage from Telstar 19 before we can conclude that first stage reuse is already "been there, done that"...

My $0.02

Hard to do stories on fairing recovery without too many pictures and videos.  When they catch one and EM says they can put out the video there will be plenty of coverage.  But it won't ever be as exciting, or as profitable as first stage recovery.

I think they are close to catching them, it will be interesting to see if they can be reused and how many times.  They are big and obviously strong enough to get through Max Q, but can they go 2 times or a huge number of times?

As for first stage landings, I'll never tire of those, I could watch 1 a day, 3 a day for a FH.
Title: Re: Fairing reuse
Post by: rpapo on 07/23/2018 10:10 am
I think they are close to catching them, it will be interesting to see if they can be reused and how many times.  They are big and obviously strong enough to get through Max Q, but can they go 2 times or a huge number of times?
If they turn out to be too close to the edge, I expect they will reinforce the design so that they will be reusable.  After all, if for one use they cost $6M each expended, but for two uses they cost, say, $9M each, including recovery costs, they still win.
Title: Re: Fairing reuse
Post by: cscott on 07/24/2018 05:01 pm
They win even at $12M including recovery costs, since it lets them step up production rate w/o building a new autoclave.
Title: Re: Fairing reuse
Post by: Lar on 07/24/2018 05:18 pm
They win even at $12M including recovery costs, since it lets them step up production rate w/o building a new autoclave.
I think you mean step up launch rate without stepping up fairing production rate.  But yeah.
Title: Re: Fairing reuse
Post by: speedevil on 07/25/2018 11:38 am
First announcement over the vidcast I think that they're going to be intending to recover the fairing before it hits, and notes of high windshear and bad weather at Mr Steven.
Title: Re: Fairing reuse
Post by: maryalice on 07/25/2018 11:54 am
Knowing  Elon, (the way he thinks) I would think he would want the boat to be computer (only) controlled at the critical moments, i.e.: communication between fairing computer and boat computer.
Title: Re: Fairing reuse
Post by: wannamoonbase on 07/25/2018 12:16 pm
Knowing  Elon, (the way he thinks) I would think he would want the boat to be computer (only) controlled at the critical moments, i.e.: communication between fairing computer and boat computer.


Agreed, I think they’d have a closed loop automatic control using radar information to guide Mr Steven to the most likely position.

How hard can that be compared to landing boosters, holding position with an ASDS or flying dragons.
Title: Re: Fairing reuse
Post by: dkovacic on 07/25/2018 01:17 pm
I have looked into Mr. Steven trajectory during Iridium 7 mission, and I guess that the fairing catch attempt was probably successful despite high winds (16 knots) and waves (2-6 meters in the area). This was found using www.windy.com

Based on marinetraffic.com AIS data for Mr. Steven https://www.marinetraffic.com/en/ais/details/ships/shipid:3439091/mmsi:338358000/imo:9744465/vessel:MR_STEVEN (https://www.marinetraffic.com/en/ais/details/ships/shipid:3439091/mmsi:338358000/imo:9744465/vessel:MR_STEVEN), it seems that the first half was caught around 12:02 UTC, around 23 minutes after launch. I think it was successful because the ship did not stop nor it circled around, but made full speed U-turn which would be expected if it caught the fairing and did not need to stop to pick it up from the sea. Also the wind conditions (16 knots in North->South direction) is pretty consistent with its speed in that segment.

After catching the fairing, it made swift turn and went to the second location with high speed, which is probably the second half floating in the sea.
Title: Re: Fairing reuse
Post by: ugordan on 07/25/2018 01:18 pm
I have looked into Mr. Steven trajectory during Iridium 7 mission, and I guess that the fairing catch attempt was probably successful despite high winds (16 knots) and waves (2-6 meters in the area).

It was not successful.
Title: Re: Fairing reuse
Post by: dkovacic on 07/25/2018 01:27 pm
I have looked into Mr. Steven trajectory during Iridium 7 mission, and I guess that the fairing catch attempt was probably successful despite high winds (16 knots) and waves (2-6 meters in the area).

It was not successful.
I just read it in the article published by Chris Bergin. Still, it is strange behavior if Mr. Steven missed the fairing.
Title: Re: Fairing reuse
Post by: cscott on 07/25/2018 01:35 pm
As an alternate interpretation: until 23 min both fairing and Mr Steven were on track, with Mr Steven steaming into the wind as expected.  Then the fairing hit the low-level high speed wind shear (as discussed on the broadcast) and rapidly changed direction/was blown "backwards".  Mr. Steven executed a high speed u turn in an attempt to catch up with new position, but was unsuccessful.  Perhaps there was also a loss of signal or some confusion there, so that the spot you indicate for "location of second fairing location" is actually (parts of?) the first fairing.

Speculation piled on speculation: the fairing actually broke in two during the wind shear event, with the transponder on the lighter half, which then got swept quickly "backwards" and is what Mr Steven initially chased.  The "second fairing location" is then actually the location of the bulk of the first fairing, which ended up closer to the original target point.

We'll know a little more when she gets back to port.  I wish we had video, though: I love a good ocean storm.
Title: Re: Fairing reuse
Post by: cscott on 07/25/2018 01:39 pm
Another alternative reading (my first thought, in fact, before I saw the AIS track): due to the high winds and waves the attempt was called off at some point out of concern for the safety of the ship and crew.  The rapid u-turn might be an "abort out of the danger zone", for instance, until visual confirmation that the fairing was in the ocean. Then Mr Steven might have backtracked back to see if the fairing was salvagable; sea state might also have caused them to abandon the salvage attempts as well out of an abundance of caution. 18' waves are no joke, and the fairing would probably make an impressive sail if it caught the wind.
Title: Re: Fairing reuse
Post by: dkovacic on 07/25/2018 01:46 pm
As an alternate interpretation: until 23 min both fairing and Mr Steven were on track, with Mr Steven steaming into the wind as expected.  Then the fairing hit the low-level high speed wind shear (as discussed on the broadcast) and rapidly changed direction/was blown "backwards".  Mr. Steven executed a high speed u turn in an attempt to catch up with new position, but was unsuccessful.  Perhaps there was also a loss of signal or some confusion there, so that the spot you indicate for "location of second fairing location" is actually (parts of?) the first fairing.

Speculation piled on speculation: the fairing actually broke in two during the wind shear event, with the transponder on the lighter half, which then got swept quickly "backwards" and is what Mr Steven initially chased.  The "second fairing location" is then actually the location of the bulk of the first fairing, which ended up closer to the original target point.

We'll know a little more when she gets back to port.  I wish we had video, though: I love a good ocean storm.
Second point is approximately five miles from the first. That would be a HUGE miss. So I would I would not agree with the interpretation that the second location is the place of the first fairing half. It could have be broken apart  (again, a piece that is built to withstand supersonic speeds, should be able to handle wind gusts). It would be more likely that it was damaged during the catch itself. Or that they abandoned the fairing and went to pickup the second one? It does not make sense.
Title: Re: Fairing reuse
Post by: dkovacic on 07/25/2018 01:50 pm
Another alternative reading (my first thought, in fact, before I saw the AIS track): due to the high winds and waves the attempt was called off at some point out of concern for the safety of the ship and crew.  The rapid u-turn might be an "abort out of the danger zone", for instance, until visual confirmation that the fairing was in the ocean. Then Mr Steven might have backtracked back to see if the fairing was salvagable; sea state might also have caused them to abandon the salvage attempts as well out of an abundance of caution. 18' waves are no joke, and the fairing would probably make an impressive sail if it caught the wind.
I like this interpretation. If they return without both halves to the port that would confirm your hypothesis.
Title: Re: Fairing reuse
Post by: cscott on 07/25/2018 01:55 pm
As an alternate interpretation: until 23 min both fairing and Mr Steven were on track, with Mr Steven steaming into the wind as expected.  Then the fairing hit the low-level high speed wind shear (as discussed on the broadcast) and rapidly changed direction/was blown "backwards".  Mr. Steven executed a high speed u turn in an attempt to catch up with new position, but was unsuccessful.  Perhaps there was also a loss of signal or some confusion there, so that the spot you indicate for "location of second fairing location" is actually (parts of?) the first fairing.

Speculation piled on speculation: the fairing actually broke in two during the wind shear event, with the transponder on the lighter half, which then got swept quickly "backwards" and is what Mr Steven initially chased.  The "second fairing location" is then actually the location of the bulk of the first fairing, which ended up closer to the original target point.

We'll know a little more when she gets back to port.  I wish we had video, though: I love a good ocean storm.
Second point is approximately five miles from the first. That would be a HUGE miss. So I would I would not agree with the interpretation that the second location is the place of the first fairing half. It could have be broken apart  (again, a piece that is built to withstand supersonic speeds, should be able to handle wind gusts). It would be more likely that it was damaged during the catch itself. Or that they abandoned the fairing and went to pickup the second one? It does not make sense.
What is the time difference between the first and second points?  If a part broke off the fairing, it would probably fall more or less straight down; it doesn't seem impossible that the part still attached to the parafoil might be able to glide for another 5 miles.  Parafoil glide ratio is 4-5ish, I believe, so 5 miles out is a wind shear incident 5000' up, neglecting wind speed effects.  I agree it's maybe not the mostly likely explanation, but it doesn't seem *impossible*.
Title: Re: Fairing reuse
Post by: cscott on 07/25/2018 01:58 pm
I like this interpretation. If they return without both halves to the port that would confirm your hypothesis.
I prefer this interpretation too, fwiw: first outing for Mr Steven in stormy conditions with a huge net and outriggers deployed as they attempt max speed; doesn't seem improbable at all that they might have started to roll and decided that caution was called for.
Title: Re: Fairing reuse
Post by: meekGee on 07/25/2018 01:59 pm
I don't think there's enough time to "try again".  The boat and fairing are on parallel tracks, with the fairing losing altitude.  They either continue to recovery, or Mr Steven says "not today" and breaks off.

I still think the fairing is supposed to overtake Mr Steven from behind, but first video will tell..

-----
ABCD: Always Be Counting Down

Title: Re: Fairing reuse
Post by: dkovacic on 07/25/2018 02:03 pm
What is the time difference between the first and second points?  If a part broke off the fairing, it would probably fall more or less straight down; it doesn't seem impossible that the part still attached to the parafoil might be able to glide for another 5 miles.  Parafoil glide ratio is 4-5ish, I believe, so 5 miles out is a wind shear incident 5000' up, neglecting wind speed effects.  I agree it's maybe not the mostly likely explanation, but it doesn't seem *impossible*.
Second point was 18 minutes later (at 12:20UTC) and up-wind. If that happened they would chase is further south.
Title: Re: Fairing reuse
Post by: BeamRider on 07/25/2018 02:06 pm
I have only heard discussion about catching “a” fairing. Will Spacex be content with recovering one fairing per flight, or is there an intention to use two recovery ships, or perhaps to create a two fairing capture system using a single vessel?

The last option was what I had initially assumed, and imagined what I think of as a “W” or two-basket design, with the ability to fold in the “wings” of the W inward to move the fairings closeer to the centerline of the vessel post-capture, and of course reduce the imbalance from catching only one fairing out of two. Given the lack of success in catching any fairings at all, my assumptions about the difficulty of it were obviously wildly optimistic!

Anyway, does anyone know what their intended path forward looks like?
Title: Re: Fairing reuse
Post by: BeamRider on 07/25/2018 02:23 pm
Re the Atlas 5 meter sep, I always assumed that extending the fairing down over the first stage was to maintain a decent aerodynamic finess ratio in going from 4 meters to 5. Probably fewer side effects than extending the nose further. But it would seem to require the fairing sep to occur before MECO and first stage sep.
Title: Re: Fairing reuse
Post by: yg1968 on 07/25/2018 02:35 pm
I have looked into Mr. Steven trajectory during Iridium 7 mission, and I guess that the fairing catch attempt was probably successful despite high winds (16 knots) and waves (2-6 meters in the area).

It was not successful.

See the post below for more on this:

Mr. Steven didn't catch the fairing. Saw it coming down, but the wind shear was too much.

https://forum.nasaspaceflight.com/index.php?topic=45846.msg1840705#msg1840705

Title: Re: Fairing reuse
Post by: cscott on 07/25/2018 05:03 pm


I have only heard discussion about catching “a” fairing. Will Spacex be content with recovering one fairing per flight, or is there an intention to use two recovery ships, or perhaps to create a two fairing capture system using a single vessel?

See discussion here: https://forum.nasaspaceflight.com/index.php?topic=46033.0
Title: Re: Fairing reuse
Post by: OnWithTheShow on 07/25/2018 09:42 pm
The clickbait headline states: "SpaceX loses multi-million dollar nose cone"

https://money.cnn.com/2018/07/25/technology/spacex-fairing-recovery-iridium-7/index.html
Title: Re: Fairing reuse
Post by: jpo234 on 07/25/2018 10:00 pm
The clickbait headline states: "SpaceX loses multi-million dollar nose cone"

https://money.cnn.com/2018/07/25/technology/spacex-fairing-recovery-iridium-7/index.html
Well, it's true, isn't it?
Title: Re: Fairing reuse
Post by: ValmirGP on 07/25/2018 10:05 pm
The clickbait headline states: "SpaceX loses multi-million dollar nose cone"

https://money.cnn.com/2018/07/25/technology/spacex-fairing-recovery-iridium-7/index.html
Well, it's true, isn't it?

As well as would be one like "SpaceX does good in catching it's litter off the pond"
Title: Re: Fairing reuse
Post by: wannamoonbase on 07/26/2018 02:25 am
I think it’s a compliment that SpaceX is getting backhanded stories of fairing recovery failing. 

No one in the history of the world has tried.  But they failed today.  I think it’s great people are paying attention and that it implies that some think SpaceX has been so successful so far that success is expected.

Wait a few months, just wait. 
Title: Re: Fairing reuse
Post by: Robotbeat on 07/26/2018 03:46 am
The clickbait headline states: "SpaceX loses multi-million dollar nose cone"

https://money.cnn.com/2018/07/25/technology/spacex-fairing-recovery-iridium-7/index.html
Well, it's true, isn't it?
No, it's misleading and does violence to the truth.
Title: Re: Fairing reuse
Post by: guckyfan on 07/26/2018 04:11 am
Have they changed it? The headline coming up from the link now says

Quote
SpaceX's latest rocket-recovery gambit misses

Still somewhat misleading IMO. Rocket recovery did not fail, fairing recovery did.

Title: Re: Fairing reuse
Post by: meekGee on 07/26/2018 05:54 am
"Gambit", heh.  Clearly they are not golfers.

-----
ABCD: Always Be Counting Down

Title: Re: Fairing reuse
Post by: Semmel on 07/26/2018 06:10 am
"Gambit", heh.  Clearly they are not golfers.

Or chess players. A gambit involves giving up some of your material to gain positional advantage. Like offering your breakfast to the gods of traffic in the hope that you dont get stuck today. Not sure a gambit is what SpaceX is doing here.. But lets not dive too deep into this.. Ill cross my fingers for their next attempt. I just wish Mr. Stephen would be housed on the east coast, they get more tries there than on the west.
Title: Re: Fairing reuse
Post by: meekGee on 07/26/2018 06:22 am
"Gambit", heh.  Clearly they are not golfers.

Or chess players. A gambit involves giving up some of your material to gain positional advantage. Like offering your breakfast to the gods of traffic in the hope that you dont get stuck today. Not sure a gambit is what SpaceX is doing here.. But lets not dive too deep into this.. Ill cross my fingers for their next attempt. I just wish Mr. Stephen would be housed on the east coast, they get more tries there than on the west.
That's what I meant.  Reference to Big Lebowski.

-----
ABCD: Always Be Counting Down

Title: Re: Fairing reuse
Post by: QuantumG on 07/26/2018 10:00 am
That's what I meant.  Reference to Big Lebowski.

-----
ABCD: Always Be Counting Down

That's just like, your opinion, man.
Title: Re: Fairing reuse
Post by: Jim on 07/26/2018 02:09 pm
Re the Atlas 5 meter sep, I always assumed that extending the fairing down over the first stage was to maintain a decent aerodynamic finess ratio in going from 4 meters to 5. Probably fewer side effects than extending the nose further. But it would seem to require the fairing sep to occur before MECO and first stage sep.

No, it was to prevent the Centaur from having to handle the aeroloads of the fairing.  And 5m fairing wasn't over the first stage, just the Centaur.
Title: Re: Fairing reuse
Post by: envy887 on 07/26/2018 03:07 pm
The clickbait headline states: "SpaceX loses multi-million dollar nose cone"

https://money.cnn.com/2018/07/25/technology/spacex-fairing-recovery-iridium-7/index.html
Well, it's true, isn't it?
No, it's not true.

SpaceX didn't lose it (as far as we know). They just fished it out of the drink instead of catching it in mid air. They have been using dunked fairings for drop tests, so it's not worthless or equivalent to "lost"
Title: Re: Fairing reuse
Post by: WindyCity on 07/26/2018 08:23 pm

Or chess players. A gambit involves giving up some of your material to gain positional advantage.

To be nitpicky and precise (and way off subject, so remove, please, if deemed inappropriate)  a gambit is an offer (or temptation) presented to a chess opponent for him or her to capture unprotected material, usually intended to gain tempo or positional advantage. What you described is called a "sacrifice," whereby in most cases a player deliberately loses an exchange to promote an attack on the enemy king. Different variations of a gambit opening are often labeled "gambit accepted" or "gambit declined". For instance, King's Gambit Accepted or Queen's Gambit Declined.

Title: Re: Fairing reuse
Post by: deruch on 07/27/2018 06:22 am
Not sure a gambit is what SpaceX is doing here.. But lets not dive too deep into this.. Ill cross my fingers for their next attempt. I just wish Mr. Stephen would be housed on the east coast, they get more tries there than on the west.

SpaceX is giving up money (the cost of added hardware and attempting recovery) for potential savings if they succeed.  Plus, colloquial usage is as a replacement for "strategy" or "ploy".  So, I'll give them a pass.  Especially as this current headline is massively improved over the original which garnered eye rolls hard enough to strain superior rectus muscles the world over.
Title: Re: Fairing reuse
Post by: Dave G on 09/10/2018 09:53 am
It seems there was no attempt to recover the fairing on today's Telesat launch.

Anyone know why?
Title: Re: Fairing reuse
Post by: nacnud on 09/10/2018 10:13 am
Latest iteration of recovery vehicles is on the other coast. They know they can get the fairing stable under chutes but keeping it dry is still a work in progress.
Title: Re: Fairing reuse
Post by: Lar on 09/10/2018 01:09 pm
Review the thread for discussion of why West coast vs East... centers around being close to Hawthorne seen as an advantage, and the East coast frequency is so high that there might not be time to incorporate lessons learned before the next catch attempt.
Title: Re: Fairing reuse
Post by: jee_c2 on 10/08/2018 05:41 am
Hi, is there any news for the latest launch? It was West coast, so it's possible to try to catch the fairing, right?
Title: Re: Fairing reuse
Post by: kdhilliard on 10/08/2018 09:06 am
Hi, is there any news for the latest launch? It was West coast, so it's possible to try to catch the fairing, right?

From @03:21 in the hosted webcast (https://youtube.com/watch?v=vr_C6LQ7mHc&t=201) (T-13:38):
Quote
For this particular mission, we're not going to be attempting to recover the fairing, however SpaceX will continue to make ongoing attempts in future launches to recover the fairing for reuse.

Mr. Steven was all dressed up for the occasion, but never left port, possible due to heavy seas.
https://twitter.com/w00ki33/status/1048630215298052097
https://twitter.com/SpaceXFleet/status/1048941012159094790

Next chance will be SSO-A (Sun Synch Express) (https://forum.nasaspaceflight.com/index.php?topic=38551.0) in the latter half of November (NET November 19, per Spaceflight Now (https://spaceflightnow.com/launch-schedule/)).

Waiting is.
Title: Re: Fairing reuse
Post by: jee_c2 on 10/08/2018 04:06 pm
Hi, is there any news for the latest launch? It was West coast, so it's possible to try to catch the fairing, right?

From @03:21 in the hosted webcast (https://youtube.com/watch?v=vr_C6LQ7mHc&t=201) (T-13:38):
Quote
For this particular mission, we're not going to be attempting to recover the fairing, however SpaceX will continue to make ongoing attempts in future launches to recover the fairing for reuse.

Mr. Steven was all dressed up for the occasion, but never left port, possible due to heavy seas.

Next chance will be SSO-A (Sun Synch Express) (https://forum.nasaspaceflight.com/index.php?topic=38551.0) in the latter half of November (NET November 19, per Spaceflight Now (https://spaceflightnow.com/launch-schedule/)).

Waiting is.

Thanks! I'm really looking forward to a successful catch!
Title: Re: Fairing reuse
Post by: billh on 10/08/2018 08:56 pm
On the SAOCOM-1A webcast the host said there would be no attempt to recover the fairing on this mission. I wonder if that was the plan all along or did something come up?
Title: Re: Fairing reuse
Post by: Lar on 10/08/2018 09:05 pm
I think the seas "came up" but those who know for sure aren't saying.
Title: Re: Fairing reuse
Post by: deruch on 10/09/2018 09:14 am
On the SAOCOM-1A webcast the host said there would be no attempt to recover the fairing on this mission. I wonder if that was the plan all along or did something come up?

I don't think it was the original plan because they hustled to get the arms and supporting booms refitted on Mr. Steven in the days leading up to the launch.  Prior to this "rearming", they had been off the ship for at least a month.  But then the ship never left port.  I suppose it's possible that was just coincidental timing, but I doubt it.  Outsider consensus seems to be that high sea states was the problem, though this is as yet unconfirmed.
Title: Re: Fairing reuse
Post by: CuddlyRocket on 10/09/2018 09:32 pm
On the SAOCOM-1A webcast the host said there would be no attempt to recover the fairing on this mission. I wonder if that was the plan all along or did something come up?

Perhaps they just didn't fancy attempting it in the dark?
Title: Re: Fairing reuse
Post by: Lar on 10/09/2018 11:30 pm
On the SAOCOM-1A webcast the host said there would be no attempt to recover the fairing on this mission. I wonder if that was the plan all along or did something come up?

Perhaps they just didn't fancy attempting it in the dark?
Sunset is marginally[1] more predictable than sea state.  So why hustle to put the arms on if they were going to call it on account of darkness?

1 - for certain values of marginal.
Title: Re: Fairing reuse
Post by: woods170 on 10/10/2018 06:18 am
On the SAOCOM-1A webcast the host said there would be no attempt to recover the fairing on this mission. I wonder if that was the plan all along or did something come up?

Perhaps they just didn't fancy attempting it in the dark?
Sunset is marginally[1] more predictable than sea state.  So why hustle to put the arms on if they were going to call it on account of darkness?

1 - for certain values of marginal.

Mr. Steven doesn't track the fairing half visually, but via radar and transponders. The system is good enough to attempt fairing catch attempts, even in darkness.
Title: Re: Fairing reuse
Post by: Lar on 10/10/2018 09:02 pm
On the SAOCOM-1A webcast the host said there would be no attempt to recover the fairing on this mission. I wonder if that was the plan all along or did something come up?

Perhaps they just didn't fancy attempting it in the dark?
Sunset is marginally[1] more predictable than sea state.  So why hustle to put the arms on if they were going to call it on account of darkness?

1 - for certain values of marginal.

Mr. Steven doesn't track the fairing half visually, but via radar and transponders. The system is good enough to attempt fairing catch attempts, even in darkness.

Thanks! my point exactly except a bit[1] less snarky.

1 - for certain values of bit.
Title: Re: Fairing reuse
Post by: CuddlyRocket on 10/10/2018 10:11 pm
On the SAOCOM-1A webcast the host said there would be no attempt to recover the fairing on this mission. I wonder if that was the plan all along or did something come up?

Perhaps they just didn't fancy attempting it in the dark?

Sunset is marginally[1] more predictable than sea state.  So why hustle to put the arms on if they were going to call it on account of darkness?

1 - for certain values of marginal.

Maybe they changed their mind? They got cold feet (or an excess of caution, if you prefer) or someone raised an objection not previously considered?

Mr. Steven doesn't track the fairing half visually, but via radar and transponders. The system is good enough to attempt fairing catch attempts, even in darkness.

I'm sure the crew is more used to tracking things whilst manouvering visually. Eyeballs are a good back-up system, but work best in daylight. This is an experimental system; perhaps someone was more comfortable conducting those experiments in daylight until they're confident that relying on radar and transponders was going to work?
Title: Re: Fairing reuse
Post by: matthewkantar on 10/11/2018 04:55 am
I would guess the fairing is probably, or will be fitted with a flashing light.
Title: Re: Fairing reuse
Post by: Semmel on 10/11/2018 08:05 pm
At the most recent launch from Vandenberg, at 19:54 in the video, you can see the fairings fly past the second stage from the view point of the stage. At 19:56, you can see a brief flash at the inside of the fairing, for half a second or so. After that, the fairing rotates such that it presents its outside to the engine exhaust. I have not seen that before.

https://youtu.be/vr_C6LQ7mHc?t=1194
Title: Re: Fairing reuse
Post by: Lars-J on 10/11/2018 09:03 pm
At the most recent launch from Vandenberg, at 19:54 in the video, you can see the fairings fly past the second stage from the view point of the stage. At 19:56, you can see a brief flash at the inside of the fairing, for half a second or so. After that, the fairing rotates such that it presents its outside to the engine exhaust. I have not seen that before.

https://www.youtube.com/watch?v=vr_C6LQ7mHc?t=1194

I disagree. IMO that 'flare' looks more like MVac exhaust interacting with the fairing. Because if that was intentional, then it should have fired far earlier since after that the worst effects of the plume have already occurred.
Title: Re: Fairing reuse
Post by: sdub on 10/12/2018 02:09 am
It looks like SpaceX was working with Mr Steven, a test fairing and a helicopter today.

https://www.teslarati.com/spacex-mr-steven-helicopter-drop-test-practice/
Title: Re: Fairing reuse
Post by: Semmel on 10/12/2018 12:03 pm
At the most recent launch from Vandenberg, at 19:54 in the video, you can see the fairings fly past the second stage from the view point of the stage. At 19:56, you can see a brief flash at the inside of the fairing, for half a second or so. After that, the fairing rotates such that it presents its outside to the engine exhaust. I have not seen that before.

https://www.youtube.com/watch?v=vr_C6LQ7mHc?t=1194

I disagree. IMO that 'flare' looks more like MVac exhaust interacting with the fairing. Because if that was intentional, then it should have fired far earlier since after that the worst effects of the plume have already occurred.

he flare is inconsistent with engine exhaust interaction. I would expect the plume to hit the entire airing surface if it hits. How comes a small element, exactly at the middle of the fairing lights up but not the edges?

Also, I dont know how far the fairing is from the plume. The camera is a wide angle camera and could observe at a large angle out so that it might see the fairing way before the fairing encounters the plume. I assume they want a certain separation of the fairing and stage to prevent thruster firings to hit the satellite. An argument against a thruster might be that the flash is roughly in the middle of the fairing, close to the center of mass. For efficient steering, you want to put the thrusters away from the center of mass.
Title: Re: Fairing reuse
Post by: Mongo62 on 10/19/2018 07:20 pm
https://twitter.com/w00ki33/status/1052845527736283136
Title: Re: Fairing reuse
Post by: OneSpeed on 10/19/2018 10:46 pm
he flare is inconsistent with engine exhaust interaction. I would expect the plume to hit the entire airing surface if it hits. How comes a small element, exactly at the middle of the fairing lights up but not the edges?

Perhaps the flare is simply light from the S2 plume reflected from a partially reflective surface inside the fairing half?
Title: Re: Fairing reuse
Post by: alang on 10/21/2018 08:40 pm
If you are embarrassed like me about making ignorant comments on this forum then that's good but remember that
all sorts of people set themselves up as experts:
https://www.sciencealert.com/spacex-falcon-9-space-rocket-giant-piece-found-beach
Title: Re: Fairing reuse
Post by: Robotbeat on 10/22/2018 12:05 am
If you are embarrassed like me about making ignorant comments on this forum then that's good but remember that
all sorts of people set themselves up as experts:
https://www.sciencealert.com/spacex-falcon-9-space-rocket-giant-piece-found-beach
Wow, that is incredibly embarrassing.
Title: Re: Fairing reuse
Post by: JamesH65 on 10/22/2018 11:45 am
If you are embarrassed like me about making ignorant comments on this forum then that's good but remember that
all sorts of people set themselves up as experts:
https://www.sciencealert.com/spacex-falcon-9-space-rocket-giant-piece-found-beach

Wow. That 'journalist' is as thick as a plank. A thick one.
Title: Re: Fairing reuse
Post by: intelati on 11/07/2018 07:04 pm
If you are embarrassed like me about making ignorant comments on this forum then that's good but remember that
all sorts of people set themselves up as experts:
https://www.sciencealert.com/spacex-falcon-9-space-rocket-giant-piece-found-beach

Wow. That 'journalist' is as thick as a plank. A thick one.

'Giant' piece ripped to shreds

Quote
And it'll be mighty difficult if the company keeps losing huge and expensive parts.

 :o
Title: Re: Fairing reuse
Post by: eeergo on 11/09/2018 12:41 am
Apologies if this was posted elsewhere before, but I don't think it's unfair to post this in several places even if it was:

https://twitter.com/nextspaceflight/status/1060531349784879104 (https://twitter.com/nextspaceflight/status/1060531349784879104)
Title: Re: Fairing reuse
Post by: JamesH65 on 11/09/2018 08:56 am
What a fantastic video. Surprising how much the fairing flexes.
Title: Re: Fairing reuse
Post by: ugordan on 11/09/2018 09:02 am
What a fantastic video. Surprising how much the fairing flexes.

Compared to an Atlas V 5xx fairing sep, this is barely any flexing. Granted, the lower end of the Atlas fairing doesn't narrow down at the sep plane like on F9 so it's natural that it'd wiggle a lot more.
Title: Re: Fairing reuse
Post by: woods170 on 11/09/2018 09:38 am
What a fantastic video. Surprising how much the fairing flexes.

Nothing that wasn't already known from this video:

https://www.youtube.com/watch?v=LtI1V624vWM
Title: Re: Fairing reuse
Post by: eeergo on 11/09/2018 12:01 pm
Perhaps more interesting than the fairings themselves is the external view of S2 with the stack on top, while in flight, with an extended view of the plume and definite visual proof that the "flashes" seen on the fairings' base as it drops away are indeed caused by MVac plume impingement and not any kind of manruvering at that stage.
Title: Re: Fairing reuse
Post by: wannamoonbase on 11/09/2018 02:32 pm
That video from the fairing camera is so awesome.  I drool at the idea of what other views and data SpaceX has collected.

This is a golden age of rocket entertainment, so much fun.
Title: Re: Fairing reuse
Post by: photonic on 12/03/2018 07:04 pm
Mr. Steven is still having bad luck:

https://mobile.twitter.com/elonmusk/status/1069679948103847939

Quote
Falcon fairing halves missed the net, but touched down softly in the water. Mr Steven is picking them up. Plan is to dry them out & launch again. Nothing wrong with a little swim.

It seems that Elon is giving up on the idea of catching them in mid-air, and is thinking about waterproofing them ...
Title: Re: Fairing reuse
Post by: Swedish chef on 12/03/2018 07:06 pm
Looks like SpaceX is going to try fairing reuse even if the halves hit water.

https://twitter.com/elonmusk/status/1069679948103847939
Quote
Falcon fairing halves missed the net, but touched down softly in the water. Mr Steven is picking them up. Plan is to dry them out & launch again. Nothing wrong with a little swim.

I suggested earlier that one could try to submerge the halves in de-ionised water until all the salt would wash away, or at least enough salt to make them fit for reuse.
Title: Re: Fairing reuse
Post by: wannamoonbase on 12/03/2018 07:52 pm
Exciting that they are looking at the reuse and that they recovered both halves.  They're clearing getting them very close to where they can predict them to be.

Reuse is great, I think they can still figure out the catching.

Does Mr Steven stay stationary, or do they move along with the fairing so they can minimize any error until it's caught? I've not heard how they do the final part, but seems that they stay in 1 spot.

Seems to me that 1 half of a 2 body rendezvous situation needs to be propulsive if the other is passive.  The F9 is under thrust when landing.  A fairing is a glider and gets into a 'best I can do' situation the closer it gets to the surface.  Grab some Tesla and F9 technology and get it working on Mr Steven. 
Title: Re: Fairing reuse
Post by: jpo234 on 12/03/2018 08:16 pm
Mr. Steven is still having bad luck:

https://mobile.twitter.com/elonmusk/status/1069679948103847939

Quote
Falcon fairing halves missed the net, but touched down softly in the water. Mr Steven is picking them up. Plan is to dry them out & launch again. Nothing wrong with a little swim.

It seems that Elon is giving up on the idea of catching them in mid-air, and is thinking about waterproofing them ...

Nothing new: https://www.tijd.be/ondernemen/defensie-ruimtevaart/recticel-trots-op-ruimtestunt/10016572.html

Quote
The company is already working on a successor for the black panels that it used at the Tesla launch. 'We are working on a hydrophobic version, to keep the pieces afloat when they fall into the sea. Reuse is one of the hobbies of SpaceX. '
Title: Re: Fairing reuse
Post by: whitelancer64 on 12/03/2018 08:23 pm
Looks like SpaceX is going to try fairing reuse even if the halves hit water.

https://twitter.com/elonmusk/status/1069679948103847939
Quote
Falcon fairing halves missed the net, but touched down softly in the water. Mr Steven is picking them up. Plan is to dry them out & launch again. Nothing wrong with a little swim.

I suggested earlier that one could try to submerge the halves in de-ionised water until all the salt would wash away, or at least enough salt to make them fit for reuse.

This was the v2.0 fairing, IIRC. I'm thinking their exterior is more hardened to salt water than the older fairings.
Title: Re: Fairing reuse
Post by: Wolfram66 on 12/03/2018 08:34 pm
Exciting that they are looking at the reuse and that they recovered both halves.  They're clearing getting them very close to where they can predict them to be.

Reuse is great, I think they can still figure out the catching.

Does Mr Steven stay stationary, or do they move along with the fairing so they can minimize any error until it's caught? I've not heard how they do the final part, but seems that they stay in 1 spot.

Seems to me that 1 half of a 2 body rendezvous situation needs to be propulsive if the other is passive.  The F9 is under thrust when landing.  A fairing is a glider and gets into a 'best I can do' situation the closer it gets to the surface.  Grab some Tesla and F9 technology and get it working on Mr Steven.


I am not sure if they are trying to fly the fairing to the boat. That seems irrational if they are doing so. Commanding the fairing parachute to fly it's land coordinates until a certain altitude, then make it fly upwind to maximize lift so that Mr. Steven can match course and speed for final flare ... just like skydivers ... maybe Elon needs some UA Army Golden Knights to demonstrate. Heck I saw on Outrageous Acts of Science 2 guys wing suit into an open door on an aircraft ... https://www.youtube.com/watch?v=YL9sNrOlK-I
Title: Re: Fairing reuse
Post by: speedevil on 12/03/2018 08:38 pm
The nice thing in principle about the fairing is you can try dropping it in a representative way a few dozen times after tipping the water out, and then do an exhaustive destructive teardown on it, and be moderately sure you've got no major issues left.

It costs helicopter time, not any sort of launch, for the interesting last ten meters.
Title: Re: Fairing reuse
Post by: whitelancer64 on 12/03/2018 08:58 pm
The nice thing in principle about the fairing is you can try dropping it in a representative way a few dozen times after tipping the water out, and then do an exhaustive destructive teardown on it, and be moderately sure you've got no major issues left.

It costs helicopter time, not any sort of launch, for the interesting last ten meters.

They don't need a helicopter if that's all they're interested in. They could do tethered drop tests into a pool.
Title: Re: Fairing reuse
Post by: speedevil on 12/03/2018 09:00 pm
The nice thing in principle about the fairing is you can try dropping it in a representative way a few dozen times after tipping the water out, and then do an exhaustive destructive teardown on it, and be moderately sure you've got no major issues left.

It costs helicopter time, not any sort of launch, for the interesting last ten meters.

They don't need a helicopter if that's all they're interested in. They could do tethered drop tests into a pool.

A pool might not catch all aspects of wave action, but I largely agree.
Title: Re: Fairing reuse
Post by: mme on 12/03/2018 10:24 pm
Mr. Steven is still having bad luck:

https://mobile.twitter.com/elonmusk/status/1069679948103847939

Quote
Falcon fairing halves missed the net, but touched down softly in the water. Mr Steven is picking them up. Plan is to dry them out & launch again. Nothing wrong with a little swim.

It seems that Elon is giving up on the idea of catching them in mid-air, and is thinking about waterproofing them ...
The fact they think they can reuse a fairing that landed in the water in no way implies that they are giving up trying to catch them. It just means they can reuse ones that survive splashdown while they continue to figure out how to catch them.

This is the SpaceX way, make the smallest/cheapest change that will collect data and/or may allow recovery and keep iterating.
Title: Re: Fairing reuse
Post by: Jcc on 12/03/2018 11:15 pm
It's not yet a "fact" that they can reuse fairings that fell in the water, but may be possible if they retrieve them quickly. Perhaps they will add a coating which adds minimal weight to protect them more.
Title: Re: Fairing reuse
Post by: mme on 12/04/2018 12:34 am
It's not yet a "fact" that they can reuse fairings that fell in the water, but may be possible if they retrieve them quickly. Perhaps they will add a coating which adds minimal weight to protect them more.
Agreed. My badly worded point was there is no evidence that SpaceX is giving up on catching the fairings before splashdown.
Title: Re: Fairing reuse
Post by: theinternetftw on 12/04/2018 01:01 am
Some quotes from Hans from today's press conference:

Quote
Irene Klotz, Aviation Week: Okay. Thanks very much, appreciate that. And for Hans, two questions. The first is how far off was Mr. Steven from payload fairing half splashdown?

Hans Koenigsmann, SpaceX: Yeah, thank you Irene. So I don't know how much we missed it by on this particular flight this morning. Or this afternoon, rather. But this is actually an older version of the fairing. There's an upgrade that we had. And that upgrade will make it easier for Mr. Steven to find the fairing. But I can't answer your question because I was just running out before I got that. However, I do know that we have some really awesome footage of Mr. Steven on the webcast. So it's definitely worth taking a look at that.

Quote
NASA Social Media: Hi, I've got two questions that came in for Hans on twitter. The first one is, you mentioned an upgraded fairing earlier, do you mean a different upgrade from the one that was used the first time in February on the PAZ mission?

Hans Koenigsmann, SpaceX: I think it is the same upgrade. This is, I could have said it the other way around, that we used an older version instead of that, but I think that is the upgrade. It's mostly related to recovery, nothing on the fairing itself.

I only highlight the above block because that now has to be reconciled with the different number of pressure equalization holes on Fairing 2.0.  Of course Hans could feel such changes are relatively minor compared to the recovery hardware, etc., but it seemed worth pointing out.

Quote
Matt Haskell, The Aerospace Geek: Hi, Matt Haskell with The Aerospace Geek. My question is for Hans. With regards to the fairings, when they don't land in the net, and they land on the salt water softly, as referred to with today's recovery, what is the capability of reusing those? Is it possible to refly those, or is the salt water damage too much?

Hans Koenigsmann, SpaceX: Uh, we're actually looking into this. It depends, we're basically so close now to the place where they go into the water, it's something we can now look closer [at], and I'm not sure what's going to happen with that, but that is certainly a possibility.

Full transcript: https://gist.github.com/theinternetftw/1bf10faf24e5a77e46fad279e8b81f10
Title: Re: Fairing reuse
Post by: Ludus on 12/04/2018 03:14 am
https://www.teslarati.com/spacex-ceo-elon-musk-new-falcon-fairing-reuse-strategy-mr-steven-missed-catch (https://www.teslarati.com/spacex-ceo-elon-musk-new-falcon-fairing-reuse-strategy-mr-steven-missed-catch)

Teslarati article about new faring approach.

It’s a lot simpler if it works this way. They would have needed a second Mr.Steven to get both halves and would still have missed some.
Title: Re: Fairing reuse
Post by: cambrianera on 12/04/2018 08:26 am
Add inflatable floaters to fairing: kiss way to minimize wetting and to dampen water impact.
Title: Re: Fairing reuse
Post by: AC in NC on 12/04/2018 02:47 pm
Add inflatable floaters to fairing: kiss way to minimize wetting and to dampen water impact.

Made me think of something like this mickey-mouse MS Paint sketch:

A brown package at the base to pop out the blue floater and a scheme (red) to block salt water/spray/rain (conceptualize it as something analogous to "saran wrap").  Float the fairing with the bottom end kept out of the water with the floater, the top curvature balancing out the other side and the saran wrap sealing the insides from salt water, spray, and rain.

The red "saran wrap" could be integrated with the parafoil perhaps.  Might even be able to obviate all or most of the need of the floater.
Title: Re: Fairing reuse
Post by: mme on 12/04/2018 03:33 pm
[url]https://www.teslarati.com/spacex-ceo-elon-musk-new-falcon-fairing-reuse-strategy-mr-steven-missed-catch/[url]

Teslarati article about new faring approach.

It’s a lot simpler if it works this way. They would have needed a second Mr.Steven to get both halves and would still have missed some.
Beyond Musk saying they could reuse the splashed down fairings, the article is pure speculation.

I don't understand the rush by people to assume that SpaceX is "giving up" catching the fairings. Just the morning of the launch SpaceX tweeted they were going to *try* to catch the fairings. At the CRS-16 presser Hans said they have upgraded recovery hardware that will make it easier for Mr. Steven to catch the hardware and that hardware was *not* on the SSO-A fairings.

Why would they try to catch them if they were giving up? Why would Hans mention better recovery hardware if they were giving up?
Title: Re: Fairing reuse
Post by: Jeff Lerner on 12/04/2018 04:26 pm
Have we ever heard if the helicopter faring drop tests were successful?...I’m not aware of Mr. Stevens ever having a success in snaring a fairing out of the air..test or after a launch....
Title: Re: Fairing reuse
Post by: cambrianera on 12/04/2018 04:38 pm
[url]https://www.teslarati.com/spacex-ceo-elon-musk-new-falcon-fairing-reuse-strategy-mr-steven-missed-catch/[url]

Teslarati article about new faring approach.

It’s a lot simpler if it works this way. They would have needed a second Mr.Steven to get both halves and would still have missed some.
Beyond Musk saying they could reuse the splashed down fairings, the article is pure speculation.

I don't understand the rush by people to assume that SpaceX is "giving up" catching the fairings. Just the morning of the launch SpaceX tweeted they were going to *try* to catch the fairings. At the CRS-16 presser Hans said they have upgraded recovery hardware that will make it easier for Mr. Steven to catch the hardware and that hardware was *not* on the SSO-A fairings.

Why would they try to catch them if they were giving up? Why would Hans mention better recovery hardware if they were giving up?

The article seems to me an accurate analisys of the situation.
Is it speculation? Yes, of course...
Title: Re: Fairing reuse
Post by: Swedish chef on 12/04/2018 04:48 pm
Why would they try to catch them if they were giving up? Why would Hans mention better recovery hardware if they were giving up?

They could be trying both. If they catch a fairing in the net then one could call it a class 1 fairing and reuse it directly to customer. Those that hit water ought to be good enough for Starlink. Both ways SpaceX saves money.  And after 5-10 uses on Starlink some other customers would probably be interested in the class 2 version if the price is right.

SSO-A was probably a fairing 2.0
https://twitter.com/nextspaceflight/status/1069704142573178881
Title: Re: Fairing reuse
Post by: RDMM2081 on 12/04/2018 05:08 pm
[url]https://www.teslarati.com/spacex-ceo-elon-musk-new-falcon-fairing-reuse-strategy-mr-steven-missed-catch/[url]

Teslarati article about new faring approach.

It’s a lot simpler if it works this way. They would have needed a second Mr.Steven to get both halves and would still have missed some.
Beyond Musk saying they could reuse the splashed down fairings, the article is pure speculation.

I don't understand the rush by people to assume that SpaceX is "giving up" catching the fairings. Just the morning of the launch SpaceX tweeted they were going to *try* to catch the fairings. At the CRS-16 presser Hans said they have upgraded recovery hardware that will make it easier for Mr. Steven to catch the hardware and that hardware was *not* on the SSO-A fairings.

Why would they try to catch them if they were giving up? Why would Hans mention better recovery hardware if they were giving up?

The article seems to me an accurate analisys of the situation.
Is it speculation? Yes, of course...

I also believe the assertion that each fairing half weighs in at 800kg is a newer number than the previously commonly quoted "about a ton" number we had before.  Teslarati is usually reliable on details, and when they say a number like this in a published article it seems likely to be a sourced insider tidbit.
Title: Re: Fairing reuse
Post by: mme on 12/04/2018 05:16 pm
Why would they try to catch them if they were giving up? Why would Hans mention better recovery hardware if they were giving up?

They could be trying both. If they catch a fairing in the net then one could call it a class 1 fairing and reuse it directly to customer. Those that hit water ought to be good enough for Starlink. Both ways SpaceX saves money.  And after 5-10 uses on Starlink some other customers would probably be interested in the class 2 version if the price is right.

SSO-A was probably a fairing 2.0
https://twitter.com/nextspaceflight/status/1069704142573178881
I agree with this assessment, trying both. My confusing is with people that think that SX has given up trying to catch them.

My interpretation of Hans' statement was not that SSO-A flew with version 1.0 but that they've been making iterative improvements to 2.0 and the one that flew on SSO-A does not have the latest improvements. I don't expect any two 2.0 fairings have been the exactly same with regard to the recovery hardware and/or software.  In my mind, 1.0 versus 2.0 is a different mold line and more room for recovery hardware. There's no way 2.0's recovery hardware and software are already "frozen."
Title: Re: Fairing reuse
Post by: lrk on 12/04/2018 06:49 pm
Add inflatable floaters to fairing: kiss way to minimize wetting and to dampen water impact.

Made me think of something like this mickey-mouse MS Paint sketch:

A brown package at the base to pop out the blue floater and a scheme (red) to block salt water/spray/rain (conceptualize it as something analogous to "saran wrap").  Float the fairing with the bottom end kept out of the water with the floater, the top curvature balancing out the other side and the saran wrap sealing the insides from salt water, spray, and rain.

The red "saran wrap" could be integrated with the parafoil perhaps.  Might even be able to obviate all or most of the need of the floater.

The bottom of the fairing already narrows at the attachment point, so keeping it out of the water probably isn't an issue.  However some method of sealing the air vents (I don't recall where those are located on Fairing 2.0) to keep out water after landing might be a bigger issue. 
Title: Re: Fairing reuse
Post by: wannamoonbase on 12/04/2018 07:26 pm
The bottom of the fairing already narrows at the attachment point, so keeping it out of the water probably isn't an issue.  However some method of sealing the air vents (I don't recall where those are located on Fairing 2.0) to keep out water after landing might be a bigger issue. 

I started thinking about that yesterday after EM mentioned they were going to try reusing them after fishing them out.

Could the fairing halves be constructed so that any openings are not on the bottoms but nearer the edges so they are safely out of the water line?
Title: Re: Fairing reuse
Post by: cambrianera on 12/04/2018 07:38 pm
Inflatable floaters with a total volume of one cubic meter can keep all the hemi fairing over the water line.
Title: Re: Fairing reuse
Post by: wannamoonbase on 12/04/2018 08:11 pm
Inflatable floaters with a total volume of one cubic meter can keep all the hemi fairing over the water line.

And what shape would that be and how would it attach to the outside of the fairing?

Seems they've resolved the re-entry and control issues, which is very exciting and maybe 90% of the work. 
Title: Re: Fairing reuse
Post by: abaddon on 12/04/2018 09:26 pm
This was the v2.0 fairing, IIRC. I'm thinking their exterior is more hardened to salt water than the older fairings.
Believe I read elsewhere on NSF this was Fairing 1.0.  Someone from SpaceX indicated that the recovery package is more capable in 2.0 in comparison.

[EDIT] And that's why I should make sure I am caught up before replying... guess it is a bit confused as to what exactly it was.
Title: Re: Fairing reuse
Post by: cambrianera on 12/05/2018 08:07 am
Inflatable floaters with a total volume of one cubic meter can keep all the hemi fairing over the water line.

And what shape would that be and how would it attach to the outside of the fairing?

Seems they've resolved the re-entry and control issues, which is very exciting and maybe 90% of the work.

There are a few experts in the field...
Title: Re: Fairing reuse
Post by: brainbit on 12/05/2018 10:59 am
There are pictures of MrStevens back in port with both fairing halves.
http://www.parabolicarc.com/2018/12/04/steven-returns-port-falcon-9-fairing/ (http://www.parabolicarc.com/2018/12/04/steven-returns-port-falcon-9-fairing/)
Title: Re: Fairing reuse
Post by: intrepidpursuit on 12/05/2018 01:31 pm
My question is, if they can reuse fairing halves even after a dunk, why even bother trying to catch them? It has proven a difficult problem to solve. The only explanation that makes sense to me is that refurb after it drops in the water is still significant enough to pay for the crazy ship.

It seems they are pursuing a less ambitious goal along with a more ambitious goal. Just seems odd to do both and odd that they didn't go for soft landing in water first before going all in on the ship.
Title: Re: Fairing reuse
Post by: MaxTeranous on 12/05/2018 02:50 pm
My question is, if they can reuse fairing halves even after a dunk, why even bother trying to catch them? It has proven a difficult problem to solve. The only explanation that makes sense to me is that refurb after it drops in the water is still significant enough to pay for the crazy ship.

It seems they are pursuing a less ambitious goal along with a more ambitious goal. Just seems odd to do both and odd that they didn't go for soft landing in water first before going all in on the ship.

This stuff isn't simple and no-one knew the specifics of how fairings would react until they tried. Go for an ambitious goal and see how it works along the way is how SpaceX operates. The "right" answer in the end may prove to be water proofing it abit and fishing them out the water, but either way they need a ship to do it and ship mods are cheap in the grand scheme of things.
Title: Re: Fairing reuse
Post by: Mark K on 12/05/2018 02:51 pm
My question is, if they can reuse fairing halves even after a dunk, why even bother trying to catch them? It has proven a difficult problem to solve. The only explanation that makes sense to me is that refurb after it drops in the water is still significant enough to pay for the crazy ship.

It seems they are pursuing a less ambitious goal along with a more ambitious goal. Just seems odd to do both and odd that they didn't go for soft landing in water first before going all in on the ship.

Based on SpaceX quotes it sounds like one reason they think they can re-use even if the fairing was in the water is that the ship was right there immediately. So exposure to water would be less. This means they would have to do almost everything to catch them anyway in terms of ship tracking and guidance. Thus I am not sure if water catch is a whole lot less than catch to be usable.
Title: Re: Fairing reuse
Post by: matthewkantar on 12/05/2018 04:11 pm
As suggested by an earlier poster, it is possible the recent fairing recovery was in a calm sea. It maybe that in a rough sea state the fairing halves would be damaged, either by the sea itself, or by recovery from a rough sea.
Title: Re: Fairing reuse
Post by: jee_c2 on 12/05/2018 05:47 pm
As it looks like, capturing the fairing is really hard, even with a fast ship like Mr, Steven.
The speed and the maneuveribility is not enough, probably.

1. Question: was the mid air capture considered? There are already experiences with doing that with helicopter (as far as I remember, the comet dust collecting probe's return part was captured in air like that, may be, other probes as well).

2. If the fairing cannot be caight like that, and landing on the water remains the option, it could be still possible to protect it from getting into the water. The strange idea is: follow the fairing , while it is descending, flying on it's parachute, with a drone (or more), and attach inflatable baloons, floating bodies (inflatable boat like) onto the fairing's bottom part. While mid air (and drone/s left), inflate those bedore landing on water surface- result way less contact with sea water, if at all.
I see, there are some fuzzy points in the process: like where and how to attach the baloons - while flying.
What kind of drones could be used? What is the needed speed, how to avoid unwanted crash while the synchronized flying (perhaps the baloons has tobe able to move around the surface of the fairing, little robots)

The drones could be brought by Mr. Steven , which is needed anyway.

Note: Of course, sending the baloons already with the fairing is too big mass penalty, I think, but I am not sure.

(I wrote this earlier, haven't seen the last posts then, but it is connected to then)
Title: Re: Fairing reuse
Post by: AC in NC on 12/05/2018 09:29 pm
1. Question: was the mid air capture considered?

Somewhere, I believe upthread, was a link to a non-SpaceX study of recovery with 1-10 ratings on various factors from Really not Suited to Best Suited.  MidAir rated quite poorly comparatively in part due to complexity, weather, time of day, etc...
Title: Re: Fairing reuse
Post by: Slarty1080 on 12/06/2018 06:17 pm
How about a large drone fitted with a line and grapple(s) and a deflated balloon and hydrogen cylinder?

Launch the drone(s) from Mr Steven when at an appropriate distance / altitude pilot the drone(s) up to the descending fairing and aim to fly over the top of it with several lines / grapples to tangle in the chute and its cords. When snagged inflate the balloon to provide extra lift and time for Mr Steven to get underneath the faring. When positioned slowly deflate the balloon so fairing drones and balloons all recovered. Parachute might not be reusable.
Title: Re: Fairing reuse
Post by: Jim on 12/06/2018 06:30 pm
How about a large drone f

What large drone?
Title: Re: Fairing reuse
Post by: kaiser on 12/06/2018 10:07 pm
How about a large drone fitted with a line and grapple(s) and a deflated balloon and hydrogen cylinder?

Launch the drone(s) from Mr Steven when at an appropriate distance / altitude pilot the drone(s) up to the descending fairing and aim to fly over the top of it with several lines / grapples to tangle in the chute and its cords. When snagged inflate the balloon to provide extra lift and time for Mr Steven to get underneath the faring. When positioned slowly deflate the balloon so fairing drones and balloons all recovered. Parachute might not be reusable.

Honestly, if you're close enough to launch a drone, maneuver, attach lines, tangle a chute, inflate balloons, do some more Rube Goldberg stuff etc, etc, just grapple it with a rope that's attach to Mr. Stevens and reel the sucker in.  Heck, have Elon on the deck dressed as Capt. Ahab shooting a whaling gun with a big suction cup tipped spear and reel it in while cackling.  Feel off topic?  Maybe.  But drones, with grappling hooks and balloons, etc just make things so complicated.  Or have the fairing dangle a lightweight line that Mr. Stevens catches and reels in.  Or, or, or. 

But most likely, just tune things up a bit better for better control, better info to the captain, etc.

I had a project where a team of MIT scientists were trying to get pilots to fly an incredibly complex and stringent flight path through the sky.  Years of work, lots of rube goldberg and other contraptions, plane modifications, chase and escort planes, etc, etc and tons of study.  You know what worked?  Adjusting the UI to the pilots.  3 or 4 iterations later on the UI and they were nailing it.  Likely something similar here; getting better info to the crew, presented better so that they can dial it in more precisely.  I know, not as sexy as drones with grappling hooks and inflatable helium balloons, but much more practical and workable.

Even pro baseball players warm up with a little throw / catch, give the crew a bit more practice and they'll probably finally dial it in with the latest set of fairings.
Title: Re: Fairing reuse
Post by: Slarty1080 on 12/06/2018 11:47 pm
How about a large drone fitted with a line and grapple(s) and a deflated balloon and hydrogen cylinder?

Launch the drone(s) from Mr Steven when at an appropriate distance / altitude pilot the drone(s) up to the descending fairing and aim to fly over the top of it with several lines / grapples to tangle in the chute and its cords. When snagged inflate the balloon to provide extra lift and time for Mr Steven to get underneath the faring. When positioned slowly deflate the balloon so fairing drones and balloons all recovered. Parachute might not be reusable.

Honestly, if you're close enough to launch a drone, maneuver, attach lines, tangle a chute, inflate balloons, do some more Rube Goldberg stuff etc, etc, just grapple it with a rope that's attach to Mr. Stevens and reel the sucker in.  Heck, have Elon on the deck dressed as Capt. Ahab shooting a whaling gun with a big suction cup tipped spear and reel it in while cackling.  Feel off topic?  Maybe.  But drones, with grappling hooks and balloons, etc just make things so complicated.  Or have the fairing dangle a lightweight line that Mr. Stevens catches and reels in.  Or, or, or. 

But most likely, just tune things up a bit better for better control, better info to the captain, etc.

I had a project where a team of MIT scientists were trying to get pilots to fly an incredibly complex and stringent flight path through the sky.  Years of work, lots of rube goldberg and other contraptions, plane modifications, chase and escort planes, etc, etc and tons of study.  You know what worked?  Adjusting the UI to the pilots.  3 or 4 iterations later on the UI and they were nailing it.  Likely something similar here; getting better info to the crew, presented better so that they can dial it in more precisely.  I know, not as sexy as drones with grappling hooks and inflatable helium balloons, but much more practical and workable.

Even pro baseball players warm up with a little throw / catch, give the crew a bit more practice and they'll probably finally dial it in with the latest set of fairings.
LOL  ;D you're probably right
Title: Re: Fairing reuse
Post by: ppb on 12/07/2018 05:41 am
Mr. Steven is obviously a fast boat. Does it chase the fairing and attempt to actively intercept it? Or is it stationary like the drone ships with the booster and let the parafoil steer to it? Or maybe a combination? This has probably been discussed on other threads. It seems downlinking the fairing's measured position and velocity to the boat or tracking it with radar and supplying that to a homing guidance law that automatically steered the ship to the intercept point might increase the capture probability.
Title: Re: Fairing reuse
Post by: edzieba on 12/07/2018 01:14 pm
It has indeed been discussed a LOT in other threads. And barring any actual evidence (which is yet to be forthcoming) the best guess is that the fairing tries to fly as straight a track as it can and Mr Steven manoeuvres under that track.

On saltwater exposure: my main concern would not be water getting into the 'concave side' of the fairing. My concern would be saltwater getting inside the actual fairing wall sandwich. The fairing is a pair of CF sheets bonded to either side of an aluminium honeycomb. That's a whole lot of tiny and nigh-impossible-to-access chambers of salt to become deposited within. That salt can attack both the aluminium honeycomb itself, and the adhesive bonding that honeyconb to the CF skins. You could power-wash the outside surfaces of the fairing all day and not touch any salt deposits within those honeycomb cells.
Title: Re: Fairing reuse
Post by: Norm38 on 12/07/2018 01:28 pm
Aren't the fairings fiberglass?  Aren't there millions of fiberglass boats in the ocean that float for decades?
Sea water isn't battery acid, it doesn't dissolve metal on contact.  Salt corrosion takes a long time.
If fairings are being reused, then invest in some anodized coatings, etc, let them splash and fish them out.

Even if they don't touch the water they will be in a marine salt spray and fog environment.  They need to be designed to get salt water on them and get washed down.
Title: Re: Fairing reuse
Post by: wannamoonbase on 12/07/2018 04:57 pm
Aren't the fairings fiberglass?  Aren't there millions of fiberglass boats in the ocean that float for decades?
Sea water isn't battery acid, it doesn't dissolve metal on contact.  Salt corrosion takes a long time.
If fairings are being reused, then invest in some anodized coatings, etc, let them splash and fish them out.

Even if they don't touch the water they will be in a marine salt spray and fog environment.  They need to be designed to get salt water on them and get washed down.

Carbon fiber, way different than fiberglass.

The fairings are subjected to loads and temperatures that no boat ever experiences. 

We'll see what they come up with.  Even if they are recovered in the net, I'm still not sold they are reuseable until we see them fly a second time, successfully.
Title: Re: Fairing reuse
Post by: Robotbeat on 12/08/2018 02:39 am
Not super different. Just lighter (and sometimes a bit stronger) than fiberglass.
Title: Re: Fairing reuse
Post by: darkenfast on 12/08/2018 05:12 am
The fairing halves have variety of openings around their half-circumferences.  If openings can be sealed, the fairing will float very high.  Splash-down at low speed should not let a bunch of water in. 
Title: Re: Fairing reuse
Post by: garcianc on 12/08/2018 04:28 pm
Aren't the fairings fiberglass?  Aren't there millions of fiberglass boats in the ocean that float for decades?
Sea water isn't battery acid, it doesn't dissolve metal on contact.  Salt corrosion takes a long time.
If fairings are being reused, then invest in some anodized coatings, etc, let them splash and fish them out.

Even if they don't touch the water they will be in a marine salt spray and fog environment.  They need to be designed to get salt water on them and get washed down.

Carbon fiber, way different than fiberglass.

The fairings are subjected to loads and temperatures that no boat ever experiences. 

We'll see what they come up with.  Even if they are recovered in the net, I'm still not sold they are reuseable until we see them fly a second time, successfully.

Absolutely. I think what some people forget is that the concern is not only corrosion or contamination to the fairing itself, but any residual contamination (or related environmental impact) that could expose future payloads. SpaceX might have decided to restrict any recovered fairing to re-fly with only certain payloads, which could be why water recovery is now an option.
Title: Re: Fairing reuse
Post by: ChrisC on 12/11/2018 12:49 pm
Here are some good views inside the fairing used for GPS III.  The NSF post I link to has them downloaded in full resolution.

More pics from encapsulation on Facebook (https://www.facebook.com/SpaceandMissileSystemsCenter/posts/2217147304982638) (credit: Lockheed Martin).
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 12/11/2018 05:59 pm
https://twitter.com/elonmusk/status/1072534901919006720

Quote
Seems likely that we’ll be able to reuse fairings that soft-landed in the ocean. May not need net at all. Would still love to see the catch happen though ⚾️ 👍
Title: Re: Fairing reuse
Post by: Prettz on 12/12/2018 07:44 pm
I wonder how much "reuse" might need to be qualified in that case. How much of what's in the interior of the fairing would be damaged by salt water spray getting all over it? Do we know enough publicly to take a stab at that?
Title: Re: Fairing reuse
Post by: Mark K on 12/12/2018 09:32 pm
I wonder how much "reuse" might need to be qualified in that case. How much of what's in the interior of the fairing would be damaged by salt water spray getting all over it? Do we know enough publicly to take a stab at that?

Wouldn't that have happened in any seas if caught in a net anyway? There will be salt water spray all over that thing even if caught in a net. I always wondered about that.
Title: Re: Fairing reuse
Post by: deruch on 12/13/2018 12:34 am
Also it will have exhaust products deposited on it, inside and out, from its fall past the lit and burning MVac regardless of whether it was caught in a net or not.  So, from a cleanliness perspective, it wouldn't surprise me to learn that SpaceX was always going to be giving them a thorough cleaning.  As long as the water exposure/immersion isn't damaging the structures or any kept interior components, it probably doesn't matter that much.  But I guess we'll see how it all plays out going forward.  After they deal with them for a while, SpaceX may decide that fishing them out of the drink isn't sufficient and re-examine other recovery methods, etc. 
Title: Re: Fairing reuse
Post by: photonic on 01/08/2019 07:14 am
Finally a video of a recovery attempt of a fairing dropped by a helicopter!

https://twitter.com/SpaceX/status/1082469132291923968

Very close, but it seems that it is hard to catch even in quiet seas. To me it looks that Mr. Steven can easily catch up with and match the forward speed of the parachute, but it might lack in ability to quickly move sideways if there are some low level winds that move it off track. My armchair idea would be to improve the controls of the parachute to aggressively correct for any sideways movements, and let Mr. Steven worry about the forward direction.

The splashdown is anyhow extremely gentle, and should leave the inside pretty dry if the waves are small. The island seen at 0:15 seems San Clemente.
Title: Re: Fairing reuse
Post by: Cheapchips on 01/08/2019 07:22 am

Tom Mueller's reply to the tweet. ;D

I know it's only a test fairing, but something flew off it at the 30 second mark when it was swinging wildly.
Title: Re: Fairing reuse
Post by: su27k on 01/08/2019 07:31 am
Seems a ship navigation/control problem, if the ship performs the right turn a few meters early it would be able to catch the fairing. Maybe they should consider letting computer autopilot run the intercept.
Title: Re: Fairing reuse
Post by: Lars-J on 01/08/2019 07:58 am
My armchair idea would be to improve the controls of the parachute to aggressively correct for any sideways movements, and let Mr. Steven worry about the forward direction.

Parachute quickly moving to the side? That’s all? :D

Well if you come up with a solution to that, you can have instant employment at any parachute manufacturer in the world.
Title: Re: Fairing reuse
Post by: kevinof on 01/08/2019 09:28 am
I think the problem is the boat they are using. Being a long waterline it will be hard to turn quickly and if the parachute deviates at all in the last seconds the boat doesn't have a chance to react.  All this in a flat sea with little wind - can't see this as a solution that would work regularly.

Maybe just waterproof the fairing as much as possible and slash it.
Title: Re: Fairing reuse
Post by: nacnud on 01/08/2019 09:34 am
I wonder if you could get a more predictable flight path with a higher wing loading. Compensate for the faster decent rate with a softer net.

Maybe they already did this with the larger net.
Title: Re: Fairing reuse
Post by: Semmel on 01/08/2019 11:13 am
I think the problem is the boat they are using. Being a long waterline it will be hard to turn quickly and if the parachute deviates at all in the last seconds the boat doesn't have a chance to react.  All this in a flat sea with little wind - can't see this as a solution that would work regularly.

Maybe just waterproof the fairing as much as possible and slash it.

The boat has to be long in order to be fast enough. Shorter boats would waste their energy by climbing their own bow wave.
Title: Re: Fairing reuse
Post by: jded on 01/08/2019 11:21 am
Maybe a hovercraft with directional fans would be quick & agile enough at the same time. But I have no idea how expensive a large custom made one could be.
Title: Re: Fairing reuse
Post by: kevinof on 01/08/2019 12:06 pm
I would have gone for a cat - more speed for less waterline and also less displacement so easier to adjust direction.

I think the problem is the boat they are using. Being a long waterline it will be hard to turn quickly and if the parachute deviates at all in the last seconds the boat doesn't have a chance to react.  All this in a flat sea with little wind - can't see this as a solution that would work regularly.

Maybe just waterproof the fairing as much as possible and slash it.

The boat has to be long in order to be fast enough. Shorter boats would waste their energy by climbing their own bow wave.
Title: Re: Fairing reuse
Post by: Jim on 01/08/2019 12:29 pm
Maybe a hovercraft with directional fans would be quick & agile enough at the same time. But I have no idea how expensive a large custom made one could be.

Hovercraft aren't quick nor agile when it comes to maneuvering.  Also, parachute would be suck in to fans.
Title: Re: Fairing reuse
Post by: racevedo88 on 01/08/2019 01:22 pm
It might be easier to do a helicopter snag recovery "Skyhook" of the fairing, don't need a fast boat just another barge of the same type as used for Falcon 9 landing and two helos. Helos take off from barge, skyhook the fairing, and bring the fairing back to the barge. Helos land on barge.
Title: Re: Fairing reuse
Post by: wannamoonbase on 01/08/2019 01:27 pm
I'm so happy to finally see a video of the fairing recovery attempt.  It's great to see that they are using the ship under power.

They are so close, they'll figure this out and I'm sure the data they collected will help them close the gap.

Very exciting and fairing recovery should be a massive advantage with the flight rate required to deploy Starlink.
Title: Re: Fairing reuse
Post by: Bananas_on_Mars on 01/08/2019 01:47 pm
My approach would be a little different, similar to arial recovery, but with a ship. Maybe it adds to much mass, i'm quite sure they considered it. The fairing needs do deploy a reasonably long line with a sinker weight. The ship has a fork in front that's lightweight and can possibly be wider than what the current net is. It can catch the line and hook up the line to some winch. Now you've essentially turned the fairing into a kite/parasail, if the ship goes fast enough you can keep it aloft for a long time. That technique would remove "almost" 1 dimension from the 3D problem that catching a fairing is. 2D for ship positioning on the surface, 1D for time.
If you have a sink rate for the fairing of 2m/s and a 200m long line, you get a window of almost 100 seconds for a successful catch, and as an advantage you don't have to match the speed of the fairing, but can drive up "behind" it with greater speed.
Title: Re: Fairing reuse
Post by: meekGee on 01/08/2019 02:15 pm
My approach would be a little different, similar to arial recovery, but with a ship. Maybe it adds to much mass, i'm quite sure they considered it. The fairing needs do deploy a reasonably long line with a sinker weight. The ship has a fork in front that's lightweight and can possibly be wider than what the current net is. It can catch the line and hook up the line to some winch. Now you've essentially turned the fairing into a kite/parasail, if the ship goes fast enough you can keep it aloft for a long time. That technique would remove "almost" 1 dimension from the 3D problem that catching a fairing is. 2D for ship positioning on the surface, 1D for time.
If you have a sink rate for the fairing of 2m/s and a 200m long line, you get a window of almost 100 seconds for a successful catch, and as an advantage you don't have to match the speed of the fairing, but can drive up "behind" it with greater speed.
Was gonna suggest exactly that.

Once snagged, winch it down, and you can then control the direction of travel too to minimize wave/wind impact.

Fwiw, the winch can be located on the parachute, so that they don't have to move the leader wire from the catch-hook to the winch, or to combine the two mechanisms.

EDIT: I have a deja vu all over again feeling here.  I think someone already proposed this like a year ago or more.
Title: Re: Fairing reuse
Post by: RobLynn on 01/08/2019 09:28 pm
Seems lateral maneuverability and ship inertia is the problem.

I would suggest a specialised lightweight drone catcher:  triangular frame holding up net arms sitting on strong simple planing pontoons - essentially just wedges with outboard motors at trailing thick end (similar to off shore power boats) under each corner.  Tow it to landing zone then release it to stay centred under fairing as it falls.  Would be light weight, maybe as little as 10-20 tonnes , so could accelerate and turn in any direction very quickly.   Could be built for a couple of million, which is likely worth it if there are still a few hundred million in fairings to be caught before Starship comes on line.
Title: Re: Fairing reuse
Post by: wannamoonbase on 01/10/2019 02:21 pm
Is there an attempt to recover the fairings with tomorrow's Iridium launch?
Title: Re: Fairing reuse
Post by: fast on 01/10/2019 02:30 pm
Why not add big inflatable bags to the fairing so it will never touch the water?
Title: Re: Fairing reuse
Post by: wannamoonbase on 01/10/2019 05:21 pm
Why not add big inflatable bags to the fairing so it will never touch the water?

Way back in history when they started the fairing recovery discussion I was thinking of something like that.  Maybe it's weight or complication.

But, now with Mr Steven getting so close to being able to catch it, I have ot think that it's just easier if they catch it, that it never touch water or have the risk of hitting water.  But also, waves, the video and pictures we've seen the ocean always looks smooth as glass.  That won't always be true.
Title: Re: Fairing reuse
Post by: OxCartMark on 01/10/2019 08:02 pm
Thanks to the powers that be for giving us this video. As stated before I remain skeptical of this approach as they are now doing it.  Perhaps some occasional success but I don't see them making routine successful catches into that net without substantial changes in method.  .And. I think there will be problems keeping it in the net once the net bears weight and the parafoil falls back to a high drag position to try to keep up its load.  Unless / hopefully there is a parachute cutaway function.  OK, that part is simple to fix if it is a problem.
Title: Re: Fairing reuse
Post by: DreamyPickle on 01/12/2019 05:01 pm
Is the strategy of catching fairings in a net at least getting closer? The recent video is cool but the system is still failing even in more controlled settings.

Maybe they should invest in waterproofing the fairing instead.
Title: Re: Fairing reuse
Post by: Lars-J on 01/12/2019 06:00 pm
Is the strategy of catching fairings in a net at least getting closer? The recent video is cool but the system is still failing even in more controlled settings.

I don’t know - do you have any previous videos to compare against to suggest if they are getting worse? If so, please share them.

Maybe they should invest in waterproofing the fairing instead.

It’s almost as if you intentionally miss Elon statements about this issue. He tweeted about it recently.
Title: Re: Fairing reuse
Post by: Lars-J on 01/12/2019 06:39 pm
BTW, here is one of his tweets suggesting that there is a parallel effort to also waterproof the fairings more:

https://twitter.com/elonmusk/status/1069679948103847939
Title: Re: Fairing reuse
Post by: AC in NC on 01/12/2019 06:51 pm
Maybe they should invest in waterproofing the fairing instead.
It’s almost as if you intentionally miss Elon statements about this issue. He tweeted about it recently.

I'm not sure the tweet "suggests" a parallel effort enough to justify calling out a fair observation.  YMMV
Title: Re: Fairing reuse
Post by: OxCartMark on 01/14/2019 02:51 am
Do we know about the bouncy raft that's behind Mr. Steven?  This goes back into late December but I haven't seen it discussed here.  Looks to me like a smaller, less maneuverable target.?.  The location of the video is just out of the port.

https://twitter.com/Eugen_Chigarin/status/1079727702553382912 (https://twitter.com/Eugen_Chigarin/status/1079727702553382912)

https://www.youtube.com/watch?v=hrC02qu2sP4&feature=youtu.be (https://www.youtube.com/watch?v=hrC02qu2sP4&feature=youtu.be)
Title: Re: Fairing reuse
Post by: OxCartMark on 01/24/2019 06:53 pm
Working on double net double fairing catch in the port:

https://www.teslarati.com/spacex-mr-steven-dual-falcon-fairing-recovery-port-testing/?mc_cid=3bc5140e6e&mc_eid=8aac13b5a7 (https://www.teslarati.com/spacex-mr-steven-dual-falcon-fairing-recovery-port-testing/?mc_cid=3bc5140e6e&mc_eid=8aac13b5a7)



Why'z it that my previous post isn't of any interest to anyone other than myself?
Title: Re: Fairing reuse
Post by: AC in NC on 01/24/2019 07:00 pm
Why'z it that my previous post isn't of any interest to anyone other than myself?

We're sadistic and like to torment you.   ;)

Is there a clear indication of how the two-net scheme works?  It wasn't obvious from my quick glance at the pictures.
Title: Re: Fairing reuse
Post by: envy887 on 01/25/2019 12:02 am
Why'z it that my previous post isn't of any interest to anyone other than myself?

It's of interest, but nobody knows what the floaty bouncy castle is for.
Title: Re: Fairing reuse
Post by: Alastor on 01/25/2019 11:53 am
Why'z it that my previous post isn't of any interest to anyone other than myself?
It's of interest, but nobody knows what the floaty bouncy castle is for.

Maybe they intend to do their first public landing by having a stunt artist ride a fairing all the way down from orbit and at the end parachute jump from it and land in the inflatable pad ?

More seriously ... Maybe that's what they use to bring the fairing at sea for helicopter pickup before their drop tests ? Or do we know for a fact that the helicopters leave the shore with the fairing in tow ?
Title: Re: Fairing reuse
Post by: su27k on 01/25/2019 11:58 am
Do we know about the bouncy raft that's behind Mr. Steven?  This goes back into late December but I haven't seen it discussed here.  Looks to me like a smaller, less maneuverable target.?.  The location of the video is just out of the port.

https://twitter.com/Eugen_Chigarin/status/1079727702553382912 (https://twitter.com/Eugen_Chigarin/status/1079727702553382912)

https://www.youtube.com/watch?v=hrC02qu2sP4&feature=youtu.be (https://www.youtube.com/watch?v=hrC02qu2sP4&feature=youtu.be)

There's speculation that this is for Dragon: https://forum.nasaspaceflight.com/index.php?topic=46136.msg1848694#msg1848694
Title: Re: Fairing reuse
Post by: nacnud on 01/25/2019 01:27 pm
My guess is it's for dragon as well, it's a fair bit denser than the fairings so perhaps a net won't work.
Title: Re: Fairing reuse
Post by: Lars-J on 01/25/2019 04:38 pm
My guess is it's for dragon as well, it's a fair bit denser than the fairings so perhaps a net won't work.

Dragon is incapable of steering, so that seems unlikely. Unless the boat pulling it is super fast and maneuverable.
Title: Re: Fairing reuse
Post by: nacnud on 01/25/2019 05:09 pm
My guess is it's for dragon as well, it's a fair bit denser than the fairings so perhaps a net won't work.

Dragon is incapable of steering, so that seems unlikely. Unless the boat pulling it is super fast and maneuverable.

True, and I have thought about that. However the crew dragon has a rather large amount of RCS/abort propellant on board. So there is a question I would have no idea about how to start answering. Or even if it's worth trying to answer rather than dismissing.

Will crew dragon, while under chutes, have enough cross range and control to hit what looks like the works largest paddling pool?  ???

PS Only see this for cargo crew dragons, initially.
Title: Re: Fairing reuse
Post by: AC in NC on 01/25/2019 05:20 pm
Will crew dragon, while under chutes, have enough cross range and control to hit what looks like the works largest paddling pool?  ???

The short answer is "No."  Jim's long answer is "No."  My long answer would be that (1) I don't think they having anything approaching the targeting accuracy from orbit that would even permit this to be entertained, (2) I doubt they have any avionics to support such an attempt, (3) I can't imagine trying to model RCS or whatever vs chutes vs. winds, and (4) doesn't it have a really toasty butt that would cause problems? 

Title: Re: Fairing reuse
Post by: nacnud on 01/25/2019 07:01 pm
1) Landing accuracy is good for dragon, I can't find a reference but I have it in my head that it's on the order of a few km
2) It knows where is it, it can be told where to land and winds before starting entry, no need for com between landing inflatable and dragon although that may help.
3) I can, I guess I'm more imaginative :D
4) You could almost pick shuttle tiles out of a furnace and not get burned, they take a few seconds to cool, youtube has some amazing vids. Small meteorites that reach the Earth are at ambient temperature or even cold, the heat all being used to ablate away the surface. These things are counter intuitive.

I'm only suggesting that the RCS would be used to have a cross range of a few hundred meters, if that, over the course of its parachute decent and really only for terminal guidance.

Still no closer to answering the questions, this is the fairing thread though...
Title: Re: Fairing reuse
Post by: OxCartMark on 01/26/2019 01:21 am
I think if you put a 9000 kg thing that isn't a fairing in the middle of that flat rubber diaphragm bottom you'd have the 9000 kg thing go down until it found its own buoyancy with the water, perhaps 2 feet down and the flat bottom would be wrapped around it the way a half inflated air matress in a pool would be if you sat crossways on the middle of it.  And the outer flotation ring would be puckered up and uninvolved with bouying the 9000 kg thing.

this is the fairing thread though...

And on the subject of fairings, although SpaceX recovered the Texas fairing not far from where they expected to I doubt they'll be able to reuse it.  Which is the way its been with all of their fairings so far.
Title: Re: Fairing reuse
Post by: photonic on 01/27/2019 06:16 pm
I think if you put a 9000 kg thing that isn't a fairing in the middle of that flat rubber diaphragm bottom you'd have the 9000 kg thing go down until it found its own buoyancy with the water, perhaps 2 feet down and the flat bottom would be wrapped around it the way a half inflated air matress in a pool would be if you sat crossways on the middle of it.  And the outer flotation ring would be puckered up and uninvolved with bouying the 9000 kg thing.

[...]

I think that in case of either a fairing or a Dragon, the point of the oversized rubber raft is not to provide flotation (since either will do that by itself in a way you described), but to prevent it from getting wet. If that works, it might save a lot on waterproofing/refurbishment after salt water exposure.

Crazy idea: since this device is obviously too small of a bullseye given the landing accuracy, could it be a test article of something that will be attached to the fairing/Dragon itself and inflated just before touchdown, MER style? The device can probably be folded into a pretty small package, and additionally only would need a gas bottle and some hatch that pops off. (I know similar ideas have been suggested up-thread, but this might be a first glimpse of the actual thing).
Title: Re: Fairing reuse
Post by: Comga on 01/27/2019 07:10 pm
1) Landing accuracy is good for dragon, I can't find a reference but I have it in my head that it's on the order of a few km
The first cargo Dragon capsule landed within 0.8 km of the target.  The second was nearly as close IIRC.  (I used to track these and compared them to the landing accuracy of Soyuz, which was and is around 11 km.)  So less than "a few km" :)

Quote
2) It knows where is it, it can be told where to land and winds before starting entry, no need for com between landing inflatable and dragon although that may help.
A Dragon will descent at a much steeper angle, partly because it's heavier, although the parachute is larger, but of course those are circular, not parafoils converting downward motion to forward motion.  A capsule should be much easier to chase than a fairing.

Quote
3) I can, I guess I'm more imaginative :D
Ditto ;)

Quote
4) You could almost pick shuttle tiles out of a furnace and not get burned, they take a few seconds to cool, youtube has some amazing vids. Small meteorites that reach the Earth are at ambient temperature or even cold, the heat all being used to ablate away the surface. These things are counter intuitive.

I'm only suggesting that the RCS would be used to have a cross range of a few hundred meters, if that, over the course of its parachute decent and really only for terminal guidance.

While they could use the RCS for targeting before drogue deployment, like a booster reentry burn, it's probably not necessary.  However, if it would help, you can bet SpaceX would eventually test it.

Quote
Still no closer to answering the questions, this is the fairing thread though...
A little bit of thread wander is as tolerable as a little bit of wind drift on a gliding fairing.  :)
Title: Re: Fairing reuse
Post by: Rondaz on 01/29/2019 02:34 pm
SpaceX fairing catcher Mr. Steven heads for Panama Canal after one last drop test

By Eric Ralph  Posted on January 29, 2019

https://www.teslarati.com/spacex-fairing-catcher-mr-steven-panama-canal-final-drop-test/
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 01/29/2019 11:22 pm
Cross posting (video attached to original post), getting closer:

https://twitter.com/spacex/status/1090400806703001600
Title: Re: Fairing reuse
Post by: cppetrie on 01/29/2019 11:28 pm
Cross posting (video attached to original post), getting closer:

https://twitter.com/spacex/status/1090400806703001600
They were all lined up and under it. If they’d have slowed the boat down as it dropped in or cut the chute loose while it was gliding above they’d have caught it no problem. Seems like they must think they’ve got it pretty darn close and confident they can close the gap using operational missions and this is why they have set out for the East coast. Will be fun to see ‘em catch the first one!
Title: Re: Fairing reuse
Post by: AC in NC on 01/29/2019 11:59 pm
Hard to tell but looked like the nose of that fairing cracked off during the drop from just above net-height.
Title: Re: Fairing reuse
Post by: OxCartMark on 01/30/2019 11:53 pm
So as I've been worried before once the weight is off the parafoil and onto the net the parafoil will fall back into a high drag position and tend to pull the fairing backward.  But also as I previously said that effect can be mitigated if they have a parafoil release mechanism which as we just saw they do.  So that failure mechanism that I was concerned about has been addressed.

As for it being too far back in the net, I think that was obvious to any of us that saw it in side view but maybe not so much from the viewpoint of the pilothouse on the ship.  So maybe they need to have a video drone beside the ship (too far out to sea for a helicopter) and make ship speed decisions from that viewpoint.
Title: Re: Fairing reuse
Post by: kaiser on 01/31/2019 03:05 am
So as I've been worried before once the weight is off the parafoil and onto the net the parafoil will fall back into a high drag position and tend to pull the fairing backward.  But also as I previously said that effect can be mitigated if they have a parafoil release mechanism which as we just saw they do.  So that failure mechanism that I was concerned about has been addressed.

As for it being too far back in the net, I think that was obvious to any of us that saw it in side view but maybe not so much from the viewpoint of the pilothouse on the ship.  So maybe they need to have a video drone beside the ship (too far out to sea for a helicopter) and make ship speed decisions from that viewpoint.

I mean they obviously had a drone or something similar side view to use for this, since that's what they gave us in the video where it didn't work well.

Camera on the deck looking straight up should be just fine, and probably better than a drone that someone has to pay attention with about field of view, where it's pointing, etc.  If you want to get fancy, download OpenCV and compute optical flow, which would give you a vector of direction change in addition to the imagery.

The camera shot they showed was a bad angle for estimating where and how the terminal catch phase is going.  Even the side angle, you really had to pay attention to check deltas.  The straight up shot gives you exactly where it's landing in both dimensions in one view.
Title: Re: Fairing reuse
Post by: libra on 02/01/2019 05:28 am
AAAh dang, so close, so close ! The freakkin' thing touched the recovery net, for a brief moment, hesitated a bit, and then committed suicide, diving into the sea.

So close ! Next time will be better.
Title: Re: Fairing reuse
Post by: alang on 02/03/2019 07:50 am
Perhaps one of the issues is wind shear or wind gradient.
If you assume that there is wind and the parafoil is gliding into wind and the boat is travelling into wind then one would expect that if the boat is maintaining a constant speed then airspeed would drop towards the end.
You might think that would increase the speed of the parafoil relative to the ship but it might become close to the stall and increase drag dramatically which could be a greater effect.
This thought is coming from some fixed wing gliding experience where one deliberately has a steeper and hence faster approach on landing to avoid a stall since one tries to land into wind and most of the time a glider flies at a best glide speed which is not much more than minimum sink which is not much faster than a stall. As one descends through the wind gradient airspeed drops.
I'd been interested to hear from a parafoil expert.

Edit: there is also curl over / wind shadow from the boat to consider. Maybe it is necessary to drop the fairing closer to the wheelhouse, which could be alarming.
Title: Re: Fairing reuse
Post by: wannamoonbase on 02/03/2019 07:53 pm
I still think the ship needs to be under control from an automated system with feedback from the fairing's position and predicted location.

The course of the ship in the most recent video looked like it was human control with that late big move to position the ship.

I think they are close and will get it sorted soon.
Title: Re: Fairing reuse
Post by: Kabloona on 02/05/2019 12:17 am
I still think the ship needs to be under control from an automated system with feedback from the fairing's position and predicted location.

The course of the ship in the most recent video looked like it was human control with that late big move to position the ship.

I think they are close and will get it sorted soon.

According to a Redditor (nginere) who says he designed the avionics for the parafoil guidance, Mr Steven is under automated control during the catch attempts. If you click on his username on Reddit, you can read his other post(s) on the subject. Link to the Reddit post is embedded in the NSF post below.

https://forum.nasaspaceflight.com/index.php?topic=45083.msg1906611#msg1906611
Title: Re: Fairing reuse
Post by: wannamoonbase on 02/05/2019 10:00 pm
I still think the ship needs to be under control from an automated system with feedback from the fairing's position and predicted location.

The course of the ship in the most recent video looked like it was human control with that late big move to position the ship.

I think they are close and will get it sorted soon.

According to a Redditor (nginere) who says he designed the avionics for the parafoil guidance, Mr Steven is under automated control during the catch attempts. If you click on his username on Reddit, you can read his other post(s) on the subject. Link to the Reddit post is embedded in the NSF post below.

https://forum.nasaspaceflight.com/index.php?topic=45083.msg1906611#msg1906611

Excellent, thanks for the information.  Perhaps they are still tuning it.
Title: Re: Fairing reuse
Post by: Lobo on 02/26/2019 04:27 pm
I haven't read all 96 pages of this thread, so not sure if this point had been made before.

While this is a very cool and novel approach, I'm wondering if it'd be more successful oif they went with a Mid Air Recovery method that LM envisioned for their Atlas partially reusable concept.

Basically a similar concept with a parafoil, but it had a long drogue above it that a helicopter could hook and then lower the Atlas RD-180 engine down to the deck of a ship.  That may be easier and more flexible to do than trying to get a ship under it with a big net.  A helicopter can intercept much higher and have a much longer time to try for a successful capture.  The ship basically just one shot at it.

Need a pair of helicopters and a ship with a deck large enough for them to take off and land from.  Nowadays there's even unmanned drone options that could be considered if they wanted to reduce the risk to pilots in poor weather of capturing a fairing half and landing on a pitching ship deck.

Or...just upgrade their PLF's halves to withstand a dunk in the ocean for a couple of hours and still be reused fully.  Then just use a boat to recover them.
Title: Re: Fairing reuse
Post by: Lar on 02/26/2019 04:48 pm
Lobo: This suggestion periodically comes up.

Read the prior thread for lots of discussion of it, and of why the approach SpaceX took is likely to be a lot lower cost and more reliable.

Yes, all 96 pages, because it's not a new topic.
Title: Re: Fairing reuse
Post by: Lobo on 03/04/2019 03:51 pm
Lar,

Ok. Thanks.
Title: Re: Fairing reuse
Post by: wannamoonbase on 03/30/2019 02:10 pm
Any word on an attempt for fairing recovery with the Arabsat launch, and other upcoming east coast launches?
Title: Re: Fairing reuse
Post by: Comga on 04/06/2019 04:59 pm
Mr. Steven has departed port also, the entire fleet is on deck for this FH mission!
   
— SpaceXFleet Updates (@SpaceXFleet) April 6, 2019
https://twitter.com/SpaceXFleet/status/1114557883813957632 (https://twitter.com/SpaceXFleet/status/1114557883813957632)

So what can Mr Steven do without arms and a net?
Something with the big, round, raft?
This may have nothing to do with fairing recovery.
Title: Re: Fairing reuse
Post by: matthewkantar on 04/06/2019 06:01 pm
Mr Steven can run down and recover fairing halves landed softly in water.
Title: Re: Fairing reuse
Post by: jstrotha0975 on 04/06/2019 09:29 pm
The fairings have been waterproofed and can be picked out of the water and be reused.
Title: Re: Fairing reuse
Post by: wannamoonbase on 04/06/2019 10:01 pm
The fairings have been waterproofed and can be picked out of the water and be reused.

Is there a source for this information?

The NSF community has talked about it, but I'm unaware of SpaceX doing such work.

Edit: I agree they are likley fishing these out of the water.
Title: Re: Fairing reuse
Post by: Raul on 04/06/2019 10:26 pm
Mr Steven can run down and recover fairing halves landed softly in water.
Mr Steven needs arms for fairing halves fish out from the water, he doesn't have any other crane. GO Searcher and GO Navigator will do that this time probably. Each of them can carry one fairing half.

The fairings have been waterproofed and can be picked out of the water and be reused.

Is there a source for this information?

The NSF community has talked about it, but I'm unaware of SpaceX doing such work.

Edit: I agree they are likley fishing these out of the water.

@elonmusk 3 Dec 2018: (http://twitter.com/elonmusk/status/1069679948103847939)
Falcon fairing halves missed the net, but touched down softly in the water. Mr Steven is picking them up. Plan is to dry them out & launch again. Nothing wrong with a little swim.
Title: Re: Fairing reuse
Post by: Lars-J on 04/12/2019 03:56 am
Does this imply that fairing catching has been abandoned as too much trouble for little gain?

Two fairings recovered intact from the water in the 2nd FH launch - and it looks like the Starlink mission will be the first to feature a reused fairing:

https://twitter.com/elonmusk/status/1116514068393680896

Title: Re: Fairing reuse
Post by: Mandella on 04/12/2019 04:08 am
Teslarati has been reporting that Mr Steven lost a couple arms a while back, which could mean that they are just going with what they have until they can get the net-boat operational again. I think they jury is still out on which will be used in the long term -- water recovery or net catching.

https://www.teslarati.com/spacex-falcon-heavy-fairing-recovery-starlink/
Title: Re: Fairing reuse
Post by: tonya on 04/12/2019 06:30 am
Does this imply that fairing catching has been abandoned as too much trouble for little gain?

Two fairings recovered intact from the water in the 2nd FH launch - and it looks like the Starlink mission will be the first to feature a reused fairing:

The benefit is cost of recovery by net vs cost of decontaminating a fairing which has been for a swim, and there's probably heavy guesswork in estimating either. Even if net recovery never proves reliable, that may still work if SpaceX can by their own customer for the ones that miss the net.
Title: Re: Fairing reuse
Post by: Pete on 04/12/2019 07:13 am
Does this imply that fairing catching has been abandoned as too much trouble for little gain?

It is possible that they chose to strengthen & waterproof the fairings a bit more, so as to make reuse/refurbishment after a water landing more practical?

Being on a FH launch, with a very generous mass budget, may have made this easier than usual, too.
Title: Re: Fairing reuse
Post by: Hobbes-22 on 04/12/2019 05:30 pm
I suspect the most difficult component to waterproof would be the acoustic insulation. That consists of foam panels, Helmholz resonators or a combination thereof. Foam needs to be fairly open to get good sound absorption, so that gets waterlogged and may have to be replaced. Resonators have internal cavities which may make it difficult to get all the water out.
Title: Re: Fairing reuse
Post by: king1999 on 04/12/2019 05:53 pm
I suspect the most difficult component to waterproof would be the acoustic insulation. That consists of foam panels, Helmholz resonators or a combination thereof. Foam needs to be fairly open to get good sound absorption, so that gets waterlogged and may have to be replaced. Resonators have internal cavities which may make it difficult to get all the water out.
I suspect that they will replace those. The fairing shell is the most expensive part.
Title: Re: Fairing reuse
Post by: WormPicker959 on 04/12/2019 08:15 pm
I suspect the most difficult component to waterproof would be the acoustic insulation. That consists of foam panels, Helmholz resonators or a combination thereof. Foam needs to be fairly open to get good sound absorption, so that gets waterlogged and may have to be replaced. Resonators have internal cavities which may make it difficult to get all the water out.
I suspect that they will replace those. The fairing shell is the most expensive part.

In the tweeted photo, the fairing on the right's foam looks damaged. It seems it would be necessary to replace, and likely the easiest part to do so as well.
Title: Re: Fairing reuse
Post by: Doesitfloat on 04/12/2019 08:54 pm
Does this imply that fairing catching has been abandoned as too much trouble for little gain?

It is possible that they chose to strengthen & waterproof the fairings a bit more, so as to make reuse/refurbishment after a water landing more practical?

Being on a FH launch, with a very generous mass budget, may have made this easier than usual, too.
Actually waterproofing wasn't that hard.
Title: Re: Fairing reuse
Post by: Nomadd on 04/15/2019 02:15 pm
 Isn't the big cost of a fairing the shell fabrication, meaning that even if the water ruined mechanisms, they wouldn't be that expensive to replace?
Title: Re: Fairing reuse
Post by: matthewkantar on 04/15/2019 03:28 pm
Just a guess; I think the worrisome spots would be where metal parts interface with composite material.
Title: Re: Fairing reuse
Post by: edzieba on 04/25/2019 01:30 pm
If it were as easy as swapping out the acoustic foam (or even all internal mechanisms) and then building a new fairing around the recovered expensive composite sandwich, SpaceX would have done it for the bragging rights already.


The fairing body itself is a sandwich of two Carbon Fibre Composite shells (one inner, one outer) and an expanded Aluminium honeycomb in between them. Most of the 'volume' of the Fairing structure is airspace. That airspace needs to be vented, as the fairing goes from 1ATM to near-vacuum and then back again. If air can get in and out of those internal spaces, then so can water during splashdown, and that's the problem SpaceX need to solve for splashdown re-use. Evaporation of salt water in those spaces leads to salt deposits in locations that cannot be easily reached (or reached at all) for cleaning and inspection. Not only is that a corrosion concern for the Aluminium honeycomb's thin walls, but also for outgassing of contaminants potentially affecting the next payload to be sat inside the fairing for launch (where intense vibrations and vacuum would happily liberate dust and volatiles).
Potential solutions include:
- Completely sealing the interstitial spaces (weight penalty, internal delaminations both more likely due to becoming pressure vessels, and will result in a fairing that cannot be re-used if breached)
- Dedicated inspection & cleaning pathways bored through the honeycomb for flex scope entry (lots of manual labour, something SpaceX like to avoid whenever possible to prevent Shuttle-reuse-itis)
- Venting channels routed to valved venting ports, to allow outgassing to the exterior of the fairings during launch, repressurisation during entry, but close to a watertight seal for splashdown (active control required, need to 'fail open' to avoid impacting primary mission)
- Total fairing structure redesign to eliminate interstitial spaces entirely, e.g. replacing Aluminium honeycomb with equivalent strength closed-cell foam (limited by dimension constraints of existing fairing volume, likely mass penalty)
Title: Re: Fairing reuse
Post by: cscott on 04/25/2019 03:43 pm


Evaporation of salt water in those spaces leads to salt deposits in locations that cannot be easily reached (or reached at all) for cleaning and inspection. Not only is that a corrosion concern for the Aluminium honeycomb's thin walls, but also for outgassing of contaminants potentially affecting the next payload to be sat inside the fairing for launch (where intense vibrations and vacuum would happily liberate dust and volatiles).

I wonder if this is the reason the first reuse is for starlink: if SpaceX can anodize or otherwise protect/qualify the aluminum surfaces, as satellite builder they can build/qualify their sats for the "liberated salt" environment at launch.

If this is successful they might start to offer discounts for other satellites willing to qualify for a salty launch environment.

This would buy time (and reduce starlink costs) while they continue to work on catching the fairing with Mr. Steven.
Title: Re: Fairing reuse
Post by: freddo411 on 04/25/2019 05:17 pm

Good summary of the design problem snipped ...


- Venting channels routed to valved venting ports, to allow outgassing to the exterior of the fairings during launch, repressurisation during entry, but close to a watertight seal for splashdown (active control required, need to 'fail open' to avoid impacting primary mission)

- Total fairing structure redesign to eliminate interstitial spaces entirely, e.g. replacing Aluminium honeycomb with equivalent strength closed-cell foam (limited by dimension constraints of existing fairing volume, likely mass penalty)


Do you know, one way or the other, if Fairing 2.0 open cell?   

I find it plausible that your last option has been implemented.   Engineering a closed cell solution, while perhaps a bit heavier, doesn't seem to pose any difficult problems.
Title: Re: Fairing reuse
Post by: Mandella on 04/25/2019 05:19 pm
They've recovered several fairings that hit the drink so they've most certainly torn them apart to see just how much gunk is getting in there, and presumably they have decided that they can afford to fly them a few times before the problem gets too severe.

Also Starlink is not a satellite that would have super sensitive scientific sensors onboard that one would have to worry about contaminating.

But I agree that, barring expensive and probably weighty redesign, it's not something they want to make a long term habit of, meaning they will keep trying to catch them before water contact.
Title: Re: Fairing reuse
Post by: OTV Booster on 04/25/2019 09:47 pm
If it were as easy as swapping out the acoustic foam (or even all internal mechanisms) and then building a new fairing around the recovered expensive composite sandwich, SpaceX would have done it for the bragging rights already.


The fairing body itself is a sandwich of two Carbon Fibre Composite shells (one inner, one outer) and an expanded Aluminium honeycomb in between them. Most of the 'volume' of the Fairing structure is airspace. That airspace needs to be vented, as the fairing goes from 1ATM to near-vacuum and then back again. If air can get in and out of those internal spaces, then so can water during splashdown, and that's the problem SpaceX need to solve for splashdown re-use. Evaporation of salt water in those spaces leads to salt deposits in locations that cannot be easily reached (or reached at all) for cleaning and inspection. Not only is that a corrosion concern for the Aluminium honeycomb's thin walls, but also for outgassing of contaminants potentially affecting the next payload to be sat inside the fairing for launch (where intense vibrations and vacuum would happily liberate dust and volatiles).
Potential solutions include:
- Completely sealing the interstitial spaces (weight penalty, internal delaminations both more likely due to becoming pressure vessels, and will result in a fairing that cannot be re-used if breached)
- Dedicated inspection & cleaning pathways bored through the honeycomb for flex scope entry (lots of manual labour, something SpaceX like to avoid whenever possible to prevent Shuttle-reuse-itis)
- Venting channels routed to valved venting ports, to allow outgassing to the exterior of the fairings during launch, repressurisation during entry, but close to a watertight seal for splashdown (active control required, need to 'fail open' to avoid impacting primary mission)
- Total fairing structure redesign to eliminate interstitial spaces entirely, e.g. replacing Aluminium honeycomb with equivalent strength closed-cell foam (limited by dimension constraints of existing fairing volume, likely mass penalty)

edzieba, I got to thinking about this problem and came up with something a bit off the wall. Long story short, use vapor pressure and condensation to flush the cells.

Here's how I picture it. With the fairing lying flat concave side up, pull a mild vacuum dropping pressure in the hex cells. Bleed water vapor into the chamber allowing vapor to enter the hex cells with rising pressure. As pressure increases the vapor in the cells condensed into water. Flip the fairing to concave side down and drop pressure forcing the liquid out the bleed holes. Repeat as necessary.

An obvious issue is that really only the cells along the center line would get the full benefit because when you flip the faring concave side down it is only the center line holes that would be covered by the condensed water. To either side the water would only collect in a corner leaving the hole exposed and the water just boiling off uselessly into vapor. The solutions is to work longitudinal zones one at a time and maybe tilt the aft end up to work the ogive area.

The first two or three cycles would get most of the air in the chamber replaced with water vapor or it could be flushed with water vapor first for more consistent condensation. Or, it might work best with a carrier gas to hold the water vapor.

Possible variations might be to place the holding jig on a shaker table or do some acoustic tricks to stir things up before expelling the water. Another might be placing heater/cooling coils on the outer surface to change the local phase change conditions independent of the rest of the chamber to get a bit more water in and out each cycle.

Preliminary testing could be as simple as a piece of honeycomb and wouldn't need the whole faring. If the bleed hole size is cooperative a simple syringe could be used to extract intentionally unexpelled water during development to gauge the number of cycles needed under varying circumstances.

One question I haven't seen answered anywhere is the aspect ratio of the honeycomb. How wide, how high. The users manual has, IIRC the outside fairing diameter, max payload diameter and the max amount of 'whip' allowable for the payload. The unknowns are the skin thickness, unstated space margins for the payload and cell diameter. Not sure it makes any difference but I've been trying to picture tall and skinny vs. short and fat with this technique.

Could somebody shoot this idea down if justified or give a hmmm, might have promise?

Phil
Title: Re: Fairing reuse
Post by: Mandella on 04/25/2019 11:47 pm
I'm obviously missing something (and it won't be for the first time) but is that complexity necessary? If the honeycomb is already perforated, why not just run a *lot* of distilled water through the whole thing for long enough to flush any substantial salt accumulation out?

Assuming the water itself doesn't cause problems, wouldn't this be the cheapest solution?
Title: Re: Fairing reuse
Post by: docmordrid on 04/26/2019 01:30 am
Water flush + a warm nitrogen gas flush to dry it?
Title: Re: Fairing reuse
Post by: OTV Booster on 04/26/2019 02:49 am
Water flush + a warm nitrogen gas flush to dry it?

My experience with getting water to go through a small hole into a blind cavity isn't very positive. A syringe could be used on each hole but then you're back to a lot of hand work.

Assumptions: The honeycomb is ~5mm. The hole is ~1mm. This is based on nothing stronger than the image that pops into my mind when I picture the fairing structure and limited experience working with/around honeycomb.

Possible alternatives: The honeycomb is much larger. The size of the hole approaches to size of the honeycomb.

If my (weak) assumptions are correct it will be a major effort getting water in and out of the cells. If the alternatives are correct the job is easy. Gently hose it out and use distilled for the last go around. Put it in the dish rack overnight and shelve it in the morning. No N2 needed.

It's probably somewhere in between but SX has gone to a lot of trouble to avoid a dunking and I don't think they'd do that if a tare down and hose out is all it would take to clean it up.

I don't recall seeing any images of the fairing interior without the sound insulation in place.

Phil
Title: Re: Fairing reuse
Post by: Hobbes-22 on 04/26/2019 07:46 am
There were some images of a fairing that had washed up (http://www.collectspace.com/ubb/Forum14/HTML/001305.html), which confirm your 5 mm estimate.

Venting would have to be done though channels cut into the honeycomb. Drilling millions of 1mm holes in the carbon fiber shell would be a time-consuming, expensive operation.
Title: Re: Fairing reuse
Post by: OTV Booster on 04/26/2019 10:56 am
There were some images of a fairing that had washed up (http://www.collectspace.com/ubb/Forum14/HTML/001305.html), which confirm your 5 mm estimate.

Venting would have to be done though channels cut into the honeycomb. Drilling millions of 1mm holes in the carbon fiber shell would be a time-consuming, expensive operation.

Thankee, sorta remember the washed up pics now that I see one again.

The venting is already there. See edzieba's description and statement of the problem just a few posts up thread.

It's hard to tell from the pic but it's possible that the inner surface is an open weave and there are no discrete holes - but I kinda doubt it. First time I've tried this but if it works there should be a crop attached showing the weave.

The outer, er uh, inner, er uh. Try again. The exposed surface is a very coarse weave. The weave shows as a square matrix and honeycomb is hexagonal so we are not seeing a pattern conformal to the cells. There are brackets attached to this surface with what look to be pop rivets (second image) that I would expect are grabbing the first surface and not passing through to the second. The pop rivets will mess up the cell(s) beneath but it's is highly localized and is a generally accepted method of attachment for honeycomb if you don't go crazy with it. The brackets are there to hold the dryer vent tubing used to circulate cool air while the payload is sitting out in the hot Florida sun and the mass is low so there will not be much load on any one rivet. That said, I wouldn't be comfortable drilling and mounting to a single coarse weave layer.

Looking at the edge (third image) it is difficult to gauge thickness. The inner surface appears thinner than the outer and it tentatively looks to be more than one layer as I'd expect. Additional layers may or may not have the same weave. Could somebody with with carbon or fiberglass layup experience chime in?

I've always thought of the fabrication process as being from the outside in but it could be the other way around. Start with the inner layer laid up on a form. Add honeycomb. Laser or water jet to punch a vent hole in each cell from the outside, sidestepping the alignment problem of drilling blind from the inside and hoping to hit each cell square on. Robots don't get bored with this type of work. Lastly the outer skin formed with prepreg carbon tape, shake and bake and vo-al-ah - a fairing blank ready to be split into halves.

The holes might be a major contributing factor to each fairing costing ~$6M and being a production bottleneck.

Sorry if this is long winded but I think my way through things with the keyboard.

Phil

Edit: minor clarity issue.
Title: Re: Fairing reuse
Post by: OTV Booster on 04/26/2019 11:38 pm
Snip from ezieba
Total fairing structure redesign to eliminate interstitial spaces entirely, e.g. replacing Aluminium honeycomb with equivalent strength closed-cell foam (limited by dimension constraints of existing fairing volume, likely mass penalty)
End snip

Set me right if I have this wrong but doesn’t closed cell foam still have air in it? ISTM this puts the fairing in the same situation as unvented cells. The foam would want to expand.


Phil
Title: Re: Fairing reuse
Post by: Lar on 04/27/2019 07:17 pm
Yes it would still want to expand. The question is whether closed cell foam could stand the pressure without rupturing. If it could, that might work. But SpaceX MUST have thought of this and tested it and rejected it... presumably.
Title: Re: Fairing reuse
Post by: OTV Booster on 04/27/2019 09:22 pm
Yes it would still want to expand. The question is whether closed cell foam could stand the pressure without rupturing. If it could, that might work. But SpaceX MUST have thought of this and tested it and rejected it... presumably.


The pressure of expansion would be:
Internal pressure + foam elasticity - ambient pressure.
This would be equal between cells leaving the action on inner and outer shells at issue. My guess is that unless the foam is really wimpie, delamination would hit before foam structure would matter. The only saving grace I can think of is if the foam elasticity makes it so stiff it adds significant structural strength. My WAG is this would be very heavy.


There is some discussion of foam properties and mass density at
[size=78%]https://www.cgrproducts.com/open-cell-vs-closed-cell-foam/ (https://www.cgrproducts.com/open-cell-vs-closed-cell-foam/)[/size]
and very prelimary research on the performance of foam in a vacuum at
https://scholarworks.rit.edu/cgi/viewcontent.cgi?referer=https://www.google.com/&httpsredir=1&article=1798&context=theses (https://scholarworks.rit.edu/cgi/viewcontent.cgi?referer=https://www.google.com/&httpsredir=1&article=1798&context=theses)
It was unclear to me which sample was closed cell.

Phil

Title: Re: Fairing reuse
Post by: fast on 04/28/2019 01:33 pm
They already equipped fairing with avionics, RCS, parachute etc.
Why not just add few inflatable bags bug enough to avoid fairing touching the water?
Title: Re: Fairing reuse
Post by: Lar on 04/28/2019 08:24 pm
They already equipped fairing with avionics, RCS, parachute etc.
Why not just add few inflatable bags bug enough to avoid fairing touching the water?
To avoid any of the fairing touching ever? Those would be very large bags I think.
Title: Re: Fairing reuse
Post by: Bananas_on_Mars on 04/28/2019 09:20 pm
Where does this idea that the honeycomb has to be vented come from? Is this something they are really doing? I haven‘t been following every answer in this thread, but from my limited experience i think delamination because of a pressure differential of 1 bar should not be a main concern...
Title: Re: Fairing reuse
Post by: OTV Booster on 04/29/2019 02:39 am
Where does this idea that the honeycomb has to be vented come from? Is this something they are really doing? I haven‘t been following every answer in this thread, but from my limited experience i think delamination because of a pressure differential of 1 bar should not be a main concern...


Laaarrrr, isn’t there an unwritten rule against telling the King his tailor is sub optimal? Make him stop!


Dude, ya got us. We are in the midsts of a shared consensual hallucination - I think. Putting grey matter in overdrive here’s what I think I remember.


Up until Mr. Stephan came this close to snagging a fairing half, maybe three months ago, Elon was adamant that a dunking could not be tolerated. After, he said a little dunking never hurt nobody. The issue of vent holes had come up previously but after the almost capture and change of SX dunking opinion I think an SCH (shared consensual halucination) took hold. The discussion hashed over old discussions re: hardware dunking, and decided that all could be referbed or replaced leaving only the fairing structure as a question as in ‘we don’t know what it needs’. Somewhere around here it became gospel that the cells are vented 


This is not to say that there are no vents. We just don’t know unless someone has a difinitive quote.


More tomorrow. I’m falling asleep.


Phil

Title: Re: Fairing reuse
Post by: Lar on 04/29/2019 02:47 am
A lot of rumours float around saying this and that. We don't dignify those. I do agree it was common consensus[1] that there was venting at the microscale for the layers.

We know there are macro scale vents to allow the atmosphere inside the fairing to escape during ascent...

1 - possibly hallucinatory
Title: Re: Fairing reuse
Post by: Bananas_on_Mars on 04/29/2019 09:47 am
I did a quick calculation, for a 5mm cell size and a nominal density of 100kg/m^3, and a pressure differential of 1 bar, we‘re nowhere near the bonding limits of epoxy resin. If i assume a bonding Cross section that equals the crosssection of the honeycomb, i get 2,7N/mm^2 of tensile stress. In reality, you will get a lot lower numbers because the resin should form a fillet with the honeycomb.

Perforated honeycomb is a thing, but it‘s connecting the individual cells with each others neighboring cells, not the outside. I assume the perforation is usually more relevant to the manufacturing, and not for special use cases.

However, i only have limited experience with composites and none with regards to rocketry, so i could be totally wrong here.
Title: Re: Fairing reuse
Post by: ames on 04/29/2019 09:57 am
At 40000 ft (12000 m) the air pressure is 18 kPa (20% of surface)

Plenty of closed cell composites flying there every second of every day.

Nick
Title: Re: Fairing reuse
Post by: cscott on 04/29/2019 02:13 pm
On the other hand, COPVs always have a metal liner.  That seems to imply that it might be hard to fully seal the composite. Even if the composite isn't fully vented, microcracks might allow interior volumes to drop to vacuum during ascent, and then this could slowly suck seawater into spaces between the layers of the composite during immersion.  Then on the next launch the infiltrated water could freeze and expand...

All of which to say that things could look very different at a microstructure level, even if at a macroscale the fairing is "watertight" and the cells are "closed".
Title: Re: Fairing reuse
Post by: Bananas_on_Mars on 04/29/2019 02:32 pm
On the other hand, COPVs always have a metal liner.  That seems to imply that it might be hard to fully seal the composite.
That‘s because the O in COPV stands for „overwrapped“. It‘s not a COPV if it‘s not wound over a liner...
A metallic liner is far better in preventing diffusion, and a lot of them are used for helium and Nitrogen under very high pressures (somewhere around 300 bar+).
That‘s nowhere near operating conditions of a fairing IMO.
However there are carbon composite pressure vessels used at cryogenic temperatures that are exposed to vacuum on one side and are working fine. The Rocketlab Electron might be known a bit here...

There are also a lot of boats made from composites...

Edit: And the fairings spend much more time in the atmosphere under parachutes before they hit the water than exposed to the vacuum of space
Title: Re: Fairing reuse
Post by: cambrianera on 04/29/2019 06:06 pm
They already equipped fairing with avionics, RCS, parachute etc.
Why not just add few inflatable bags bug enough to avoid fairing touching the water?
To avoid any of the fairing touching ever? Those would be very large bags I think.

Not that large.
A standard slide/raft for airplane exit would be enough.
Title: Re: Fairing reuse
Post by: edzieba on 05/01/2019 04:51 pm
A fairly basic need for the inner honeycomb to be vented is initial assembly: both composite layup and multi-element bonding (the fairings could either be two discrete CF layups cured then bonded around the metal honeycomb core, or the layup could be directly onto the core) require vacuum bagging (and potentially even autoclaving) as a necessary part of the process - without it you get big epoxy-wet mess that has no more strength than garden variety fibreglass.
Title: Re: Fairing reuse
Post by: Bananas_on_Mars on 05/01/2019 06:04 pm
A fairly basic need for the inner honeycomb to be vented is initial assembly: both composite layup and multi-element bonding (the fairings could either be two discrete CF layups cured then bonded around the metal honeycomb core, or the layup could be directly onto the core) require vacuum bagging (and potentially even autoclaving) as a necessary part of the process - without it you get big epoxy-wet mess that has no more strength than garden variety fibreglass.
The only „clean“ method for processing honeycomb seems to be with prepreg.

Ok, so even if it‘s needed to vent the honeycomb layer, it can be done with perforated honeycomb and a few vents. Most important, if they are only necessary for autoclave curing, there‘s no reason not to plug those vents afterwards.
Title: Re: Fairing reuse
Post by: Bananas_on_Mars on 05/13/2019 01:40 pm
Starlink fairing on Twitter (https://twitter.com/elonmusk/status/1127388838362378241?s=21)

Does it look to anybody else like there‘s no acoustic foam inside the Starlink fairing?
Title: Re: Fairing reuse
Post by: speedevil on 05/13/2019 08:56 pm
Starlink fairing on Twitter (https://twitter.com/elonmusk/status/1127388838362378241?s=21)

Does it look to anybody else like there‘s no acoustic foam inside the Starlink fairing?

The fairing is 5.2m OD, and 5.2m-2" ID or so - before flexing an any coatings.
The maximum published payload diameter is not the (say) 5.1m that it may flex into, but 4.6m.

Attempting to measure the ratio of the diameter of the fairing to the payload diameter and scaling to 5.2 gives me 4.44m.
I think it is reasonably likely it does not exceed 4.6m. (lens distortion would make it look bigger)

The payload size at least does not seem to have made them remove the foam.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 05/15/2019 09:39 am
I know SpaceX intended to reuse fairings for the Starlink mission but do we have confirmation that they actually are?

The mission presskit talks about the reused booster but makes no mention of the fairings.
Title: Re: Fairing reuse
Post by: TorenAltair on 05/15/2019 12:20 pm
I know SpaceX intended to reuse fairings for the Starlink mission but do we have confirmation that they actually are?

The mission presskit talks about the reused booster but makes no mention of the fairings.

I assume it will be later this year.
The tweet was "Both fairing halves recovered. Will be flown on Starlink 💫 mission later this year."

I think they need a bit more time than about 4 weeks to check the fairing in detail and make it flight-ready again.
Title: Re: Fairing reuse
Post by: Bananas_on_Mars on 05/24/2019 05:05 am
Starlink fairing on Twitter (https://twitter.com/elonmusk/status/1127388838362378241?s=21)

Does it look to anybody else like there‘s no acoustic foam inside the Starlink fairing?

Seems like I was correct, no acoustic foam visible inside the  just recovered Starlink fairings (https://twitter.com/elonmusk/status/1131783775396909056?s=21).

Title: Re: Fairing reuse
Post by: nacnud on 05/24/2019 09:54 am
Those tweets show a shiny cap (stainless steel?) on each fairing. Is this something we've seen before?
Title: Re: Fairing reuse
Post by: scr00chy on 05/24/2019 10:19 am
Those tweets show a shiny cap (stainless steel?) on each fairing. Is this something we've seen before?
Yes, we've seen it a few times before. Seems to be a newer generation fairing. Check out my article (https://www.elonx.net/did-spacex-quietly-introduce-an-upgraded-reusable-fairing-is-mr-steven-now-obsolete/) where I analyzed the whole situation.
Title: Re: Fairing reuse
Post by: nacnud on 05/24/2019 11:02 am
Thanks
Title: Re: Fairing reuse
Post by: wannamoonbase on 05/24/2019 07:54 pm
Looking forward to fairing reuse in the very near future.

It's cool that this is also becoming routine.
Title: Re: Fairing reuse
Post by: speedevil on 05/25/2019 11:01 am
Seems like I was correct, no acoustic foam visible inside the  just recovered Starlink fairings (https://twitter.com/elonmusk/status/1131783775396909056?s=21).
The foam likely adds several hundred kilos to the fairing too, or several dozen kilos to payload.
And lightens the fairing by a nontrivial percentage.

They also now have good data on accoustic and other properties of the naked fairing, which might allow for payloads ~20cm larger in diameter in some cases.
Title: Re: Fairing reuse
Post by: Bananas_on_Mars on 05/25/2019 11:07 am
Seems like I was correct, no acoustic foam visible inside the  just recovered Starlink fairings (https://twitter.com/elonmusk/status/1131783775396909056?s=21).
The foam likely adds several hundred kilos to the fairing too, or several dozen kilos to payload.
And lightens the fairing by a nontrivial percentage.

They also now have good data on accoustic and other properties of the naked fairing, which might allow for payloads ~20cm larger in diameter in some cases.

In my opinion, it‘s not about the added payload space, but not having to replace the foam after exposure to seawater. Should help with reuse ;-)

If the satellites are build to withstand collisions during deployment, they should also be able to be designed to withstand the increased acoustic loads.
Title: Re: Fairing reuse
Post by: scr00chy on 05/25/2019 11:11 am
In my opinion, it‘s not about the added payload space, but not having to replace the foam after exposure to seawater. Should help with reuse ;-)

If the satellites are build to withstand collisions during deployment, they should also be able to be designed to withstand the increased acoustic loads.
Might be a little bit of everything.

-Reduces total mass
-Provides more space in the fairing
-Helps with fairing recovery
-Reduces costs
Title: Re: Fairing reuse
Post by: wannamoonbase on 05/25/2019 04:12 pm
In my opinion, it‘s not about the added payload space, but not having to replace the foam after exposure to seawater. Should help with reuse ;-)

If the satellites are build to withstand collisions during deployment, they should also be able to be designed to withstand the increased acoustic loads.
Might be a little bit of everything.

-Reduces total mass
-Provides more space in the fairing
-Helps with fairing recovery
-Reduces costs

I think your list is spot on.  Being the rocket owner and payload designer could certainly have benefits in designing the payload for the environment.

Can't wait to see fairing reuse, it will save about $100,000 per satellite.  Likely EM wants 10+ reuses.

To think of launching 13+ metric tons to LEO with only expending the upper stage. 

That's amazing!
Title: Re: Fairing reuse
Post by: wannamoonbase on 06/25/2019 03:35 pm
Fantastic, they finally caught one in the net.  Hopefully we see a lot more attempts and success now.

Recovering $6 million in hardware is an exciting development.

I have to admit when EM said they were going to try I thought 'no way' but quickly reminded myself of what SpaceX has already accomplished.

I'm looking forward to seeing some F9 stacks with sooty tops and bottoms.
Title: Re: Fairing reuse
Post by: JazzFan on 06/25/2019 04:44 pm
Fantastic, they finally caught one in the net.  Hopefully we see a lot more attempts and success now.

Recovering $6 million in hardware is an exciting development.

I have to admit when EM said they were going to try I thought 'no way' but quickly reminded myself of what SpaceX has already accomplished.

I'm looking forward to seeing some F9 stacks with sooty tops and bottoms.

This is one thing that I never thought they would accomplish.  Betting against SpaceX is making me look bad.
Title: Re: Fairing reuse
Post by: armchairfan on 06/25/2019 05:50 pm
I found this fairing recovery snippet on youtube. It was apparently in the SpaceX broadcast.
https://www.youtube.com/watch?v=H-EVcg_48sk (https://www.youtube.com/watch?v=H-EVcg_48sk)
Title: Re: Fairing reuse
Post by: Mandella on 06/25/2019 05:51 pm
Fantastic, they finally caught one in the net.  Hopefully we see a lot more attempts and success now.

Recovering $6 million in hardware is an exciting development.

I have to admit when EM said they were going to try I thought 'no way' but quickly reminded myself of what SpaceX has already accomplished.

I'm looking forward to seeing some F9 stacks with sooty tops and bottoms.

This is one thing that I never thought they would accomplish.  Betting against SpaceX is making me look bad.

Yeah I'm on record too saying they've "obviously given up fairing catch."

Glad I didn't put any money on it!
Title: Re: Fairing reuse
Post by: OxCartMark on 06/25/2019 06:49 pm
I don't recall that being in the original webcast.  I think they retroactively edited it in for history and out of an abundance of happiness.  There is precedent, remember when on FH #1 they inadvertently showed the 2 side booster onboard views but they were the same one duplicated ~ and then they edited to be correct hours later.?.  I know that when I tried to find the video this morning to play some of the later deployments it wasn't available, so I think it was pulled down then fiddled with a bit.  Does anyone recall differently, did you see the fairing succeeding last night?

So now we've got a fairing in the net but seemingly precariously near the edge of the net and 800 miles to go.  Hmm, reminds me of the Arabsat center core.  I hopefully its securely therein when we next see it.  It is probably a difficult task if possible at all for them to get up there and then to find a hard point on the fairing that they can tie a securing line to.  And... a light fairing with large area might be cause for Miz Goat Ree to not be able to use her blazing speed on the way back for fear of the fairing getting blown about. I'm interested to know the speed they're coming back at if anyone has deep sea AIS.
Title: Re: Fairing reuse
Post by: rugo on 06/25/2019 06:56 pm
I don't recall that being in the original webcast.
I am sure that I saw it in the original webcast.
Title: Re: Fairing reuse
Post by: CuddlyRocket on 06/25/2019 07:02 pm
I don't recall that being in the original webcast. ... Does anyone recall differently, did you see the fairing succeeding last night?

Yes, it was in the original broadcast. You can see this in Tim Dodd's (Everyday Astronaut) live reaction video of the launch at 1:47:27.

https://www.youtube.com/watch?v=Vp-bX61xID4

Title: Re: Fairing reuse
Post by: Lar on 06/25/2019 07:04 pm
Fantastic, they finally caught one in the net.  Hopefully we see a lot more attempts and success now.

Recovering $6 million in hardware is an exciting development.

I have to admit when EM said they were going to try I thought 'no way' but quickly reminded myself of what SpaceX has already accomplished.

I'm looking forward to seeing some F9 stacks with sooty tops and bottoms.
Technically, this catch didn't recover the whole 6M, it was only one fairing half (presumably what we sometimes hear referred to as the active half). The other half was (presumably?) fished out by another GO boat on station.

It will be interesting if they go with two catchers, or catch the active half and fish out the half with less gear (either with the same catcher, or with another on station vessel), or two catches in one glove, or what...
Title: Re: Fairing reuse
Post by: freddo411 on 06/25/2019 08:06 pm
I don't recall that being in the original webcast.  I think they retroactively edited it in for history and out of an abundance of happiness.  There is precedent, remember when on FH #1 they inadvertently showed the 2 side booster onboard views but they were the same one duplicated ~ and then they edited to be correct hours later.?.  I know that when I tried to find the video this morning to play some of the later deployments it wasn't available, so I think it was pulled down then fiddled with a bit.  Does anyone recall differently, did you see the fairing succeeding last night?

So now we've got a fairing in the net but seemingly precariously near the edge of the net and 800 miles to go.  Hmm, reminds me of the Arabsat center core.  I hopefully its securely therein when we next see it.  It is probably a difficult task if possible at all for them to get up there and then to find a hard point on the fairing that they can tie a securing line to.  And... a light fairing with large area might be cause for Miz Goat Ree to not be able to use her blazing speed on the way back for fear of the fairing getting blown about. I'm interested to know the speed they're coming back at if anyone has deep sea AIS.

Hard to tell exactly how the fairing is resting in the net.    I suspect that net is designed so that the fairing can slide into the middle, then the net can be lowered so that all is on the deck.     

Even if the fairing is stuck a on the edge of the net, I bet there is a seaman willing to climb the net and secure lines.   Haven't you seen Deadliest Catch?   Those dudes are brave/crazy.
Title: Re: Fairing reuse
Post by: wannamoonbase on 06/25/2019 09:37 pm
Hard to tell exactly how the fairing is resting in the net.    I suspect that net is designed so that the fairing can slide into the middle, then the net can be lowered so that all is on the deck.     

Even if the fairing is stuck a on the edge of the net, I bet there is a seaman willing to climb the net and secure lines.   Haven't you seen Deadliest Catch?   Those dudes are brave/crazy.

I think they'd be able to manage the net, by how it is lowered, then pulling on it, to position the fairing where they want it.

How they deal with 2 halves at the same time, I assume there will be 2 similar net equipment ships soon.  Then jet back to port to unload before weather becomes an issue.
Title: Re: Fairing reuse
Post by: Alastor on 06/26/2019 12:32 pm
Technically, this catch didn't recover the whole 6M, it was only one fairing half (presumably what we sometimes hear referred to as the active half). The other half was (presumably?) fished out by another GO boat on station.

Did we hear any recent reference to an active half from SpaceX ?
I remember that this terminology was used in the early tests but I always understood it as meaning that they at the time equipped only one half with recovery gear to conserve mass during the early experimental phase.
I think now that both halves are equipped with recovery gear, they can both be understood to be "active".

They'll probably soon start equipping another boat with a recovery net if they feel they have this catching thing more or less under control. The return on investment will be quite quick if they car recover fairings even with a 20~25% catch rate I believe.
Title: Re: Fairing reuse
Post by: scr00chy on 06/26/2019 12:35 pm
Active/passive has nothing to do with recovery. It's used to differentiate that, during separation, one fairing pushes the other fairing away. So one half is actively pushing, while the other half is passively being pushed.

During the early fairing recovery attempts, only one half (the passive one, I think) was equipped with chutes. But since fairing 2.0 came along, both halves have been equipped with recovery hardware.
Title: Re: Fairing reuse
Post by: Lar on 06/26/2019 04:27 pm
Thanks for that clarification, scr00chy

Still an open question how they operationalize this. lots and lots of prior discussion about one ship two catches, two ships, etc...
Title: Re: Fairing reuse
Post by: CuddlyRocket on 06/26/2019 08:53 pm
Now they've caught a fairing half they can compare its condition with those they've recovered from the sea and determine whether there's any significant benefit from catching them.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 07/03/2019 10:35 pm
Here’s part of what a fairing goes through to be recovered:

https://twitter.com/spacex/status/1146546495241371649

Quote
View from the fairing during the STP-2 mission; when the fairing returns to Earth, friction heats up particles in the atmosphere, which appear bright blue in the video
Title: Re: Fairing reuse
Post by: wannamoonbase on 07/04/2019 04:39 am
The fairing re-entry video is one of SpaceX’s most amazing to date. 

Hopefully the structure and coating can handle that heat load. 

But what a light show!
Title: Re: Fairing reuse
Post by: OneSpeed on 07/04/2019 06:42 am
For those without Twitter:

Edit: added the catch.
Title: Re: Fairing reuse
Post by: Alastor on 07/04/2019 08:31 am
For those without Twitter:

Edit: added the catch.

A few interesting observations :
 - Around 30s in the reentry video, we see 2 holes forming in the middle of the fairing letting air/plasma flow pass through. Given the symmetry it seems intentional, and I think it's likely to help the passive stability of the faring during reentry.
 - At the end of the video, while under the parachute, we see a lot of white flashes that seemingly come from above the camera. These look like they are RCS thrusters in action, probably to help steer the whole thing or to keep the faring in a good orientation relative to the parafoil.
 - In the landing video, the faring is coming in perpendicular to the boat, when it was previously in images from tests coming from behind. They might have changed their strategy for catching it.
 - They land at the very beginning of the net, and at the center laterally. It seems it's not close to missing it at all and that on the contrary, they didn't use much of the margin they had. All things considered, that's a very good catch I think.

Now I wish they would release the video of the full descent !
I'd love to see these parafoils deploying and the  faring in full landing action !
Title: Re: Fairing reuse
Post by: scr00chy on 07/04/2019 08:58 am
I'd love to see these parafoils deploying and the  faring in full landing action !
You can see parachute deployment in the drop test video:

https://youtu.be/4hwbmJLM3_g
Title: Re: Fairing reuse
Post by: EspenU on 07/04/2019 10:05 am
A few interesting observations :
 - Around 30s in the reentry video, we see 2 holes forming in the middle of the fairing letting air/plasma flow pass through. Given the symmetry it seems intentional, and I think it's likely to help the passive stability of the faring during reentry.
The fairings have vents to equalize pressure inside the fairing during ascent. Could the holes we see be those vents?
Title: Re: Fairing reuse
Post by: cscott on 07/04/2019 11:39 am
A few interesting observations :
 - Around 30s in the reentry video, we see 2 holes forming in the middle of the fairing letting air/plasma flow pass through. Given the symmetry it seems intentional, and I think it's likely to help the passive stability of the faring during reentry.
 - At the end of the video, while under the parachute, we see a lot of white flashes that seemingly come from above the camera. These look like they are RCS thrusters in action, probably to help steer the whole thing or to keep the fairing in a good orientation relative to the parafoil.

I'm pretty sure these are just the fairing vent/access holes.  They are not 'formed', they are present at launch -- although IIRC they usually have paper covers on.  Obviously SpaceX carefully designed them for this dual purpose, and I agree they probably have a role in stabilization.  It seems that you *could* control attitude by manipulating them, but from the video it doesn't appear they are doing that.

Cold gas thrusters wouldn't give white sparks.  Generally the nitrogen thrusters are entirely out of the view of this camera.  We have video of them, though if you hunt through the archives: from the second stage camera we've seen the fairing halves maneuvering as they fall away just after separation.  The thrusters give more diffuse clouds, sometimes with a nebula effect.  In this video you can see them as full frame going white briefly.  Frequently just after separation, then at a slower rate once re-entry gets underway.

The white sparks are probably just some ablative heat shield on the nose of the fairing doing its job.  On Twitter I heard a suggestion they were aluminum sparks (in which case it would be an "unintentional ablative heat shield").  Given the cross fade that happens at that point, I had a fleeting thought that it might be the parachute drogue mortars firing, but on reflection I don't think the timing is right for that.
Title: Re: Fairing reuse
Post by: cferreir on 07/04/2019 01:41 pm
Ok so I have to throw this out there......

Do you guys think that an astronaut would survive the fall from space inside that fairing? Environment looks relatively benign (as far as reentry goes....).
Title: Re: Fairing reuse
Post by: ThatOldJanxSpirit on 07/04/2019 02:16 pm
Thoughts on the orientation of the fairing relative to the parachute. Mounting sideways makes good sense for touchdowns as it eliminates ‘slap down’ loads from nose high / nose low landings. A secondary consideration is that the more ‘draggy’ fairing would better damp down fore / aft pendulum oscillations.
Title: Re: Fairing reuse
Post by: Semmel on 07/04/2019 02:20 pm
Ok so I have to throw this out there......

Do you guys think that an astronaut would survive the fall from space inside that fairing? Environment looks relatively benign (as far as reentry goes....).

Well, the question is how he gets there in the first place... but assuming he rides inside the payload bay and sticks somehow to the fairing during fairing separation and the fairing structurally survives the concentrated mass and the control computer can cope with the added mass, it might be survivable. All these assumptions aside (which are technical detais for this problem, really).. the g-loads might black him or her out or kill outright. I have no idea how fast the fairing decelerates. Probably fast.
Title: Re: Fairing reuse
Post by: Lar on 07/04/2019 02:38 pm
I am late to the party so, do we know if that is true color or IR or some false color? Blue is an unexpected color to see without some yellow or red on the way to blue.

Ok so I have to throw this out there......

Do you guys think that an astronaut would survive the fall from space inside that fairing? Environment looks relatively benign (as far as reentry goes....).

Well, the question is how he gets there in the first place... but assuming he rides inside the payload bay and sticks somehow to the fairing during fairing separation and the fairing structurally survives the concentrated mass and the control computer can cope with the added mass, it might be survivable. All these assumptions aside (which are technical detais for this problem, really).. the g-loads might black him or her out or kill outright. I have no idea how fast the fairing decelerates. Probably fast.

C.F. the sequences in the novel Starship Trooper in which powersuit (essentially a spacesuit) clad marines descend to a planetary surface with the inital descent in a "pod" which could be fairing shaped. 

Also C.F. the 1960s studies about emergency reentry techniques.
Title: Re: Fairing reuse
Post by: speedevil on 07/04/2019 02:41 pm
I am late to the party so, do we know if that is true color or IR or some false color? Blue is an unexpected color to see without some yellow or red on the way to blue.

Ok so I have to throw this out there......

Do you guys think that an astronaut would survive the fall from space inside that fairing? Environment looks relatively benign (as far as reentry goes....).

Well, the question is how he gets there in the first place... but assuming he rides inside the payload bay and sticks somehow to the fairing during fairing separation and the fairing structurally survives the concentrated mass and the control computer can cope with the added mass, it might be survivable. All these assumptions aside (which are technical detais for this problem, really).. the g-loads might black him or her out or kill outright. I have no idea how fast the fairing decelerates. Probably fast.

C.F. the sequences in the novel Starship Trooper in which powersuit (essentially a spacesuit) clad marines descend to a planetary surface with the inital descent in a "pod" which could be fairing shaped. 

Also C.F. the 1960s studies about emergency reentry techniques.
https://en.wikipedia.org/wiki/MOOSE

(https://upload.wikimedia.org/wikipedia/en/c/c5/Operation_MOOSE_%28figure_112%29.PNG)

As the sole on-topic content of this post - the fairing seperated at 3185m/s.
Title: Re: Fairing reuse
Post by: Stan-1967 on 07/04/2019 02:51 pm
Ok so I have to throw this out there......

Do you guys think that an astronaut would survive the fall from space inside that fairing? Environment looks relatively benign (as far as reentry goes....).

Well, the question is how he gets there in the first place... but assuming he rides inside the payload bay and sticks somehow to the fairing during fairing separation and the fairing structurally survives the concentrated mass and the control computer can cope with the added mass, it might be survivable. All these assumptions aside (which are technical detais for this problem, really).. the g-loads might black him or her out or kill outright. I have no idea how fast the fairing decelerates. Probably fast.

My "bold" added above.  Lots of Velcro strapping you in by the fairing CG is obviously part of this solution. :)  I think inside the top conical fairings of FH side booster is a more interesting place for a ride along.
Title: Re: Fairing reuse
Post by: Robotbeat on 07/04/2019 03:22 pm
Ok so I have to throw this out there......

Do you guys think that an astronaut would survive the fall from space inside that fairing? Environment looks relatively benign (as far as reentry goes....).
yes.
Title: Re: Fairing reuse
Post by: OxCartMark on 07/04/2019 04:46 pm
A secondary consideration is that the more ‘draggy’ fairing would better damp down fore / aft pendulum oscillations.

I'm not sure if you are referring specifically to the one forward surge of the parafoil shortly after opening or more generally, but if you're referring to that, its necessary.  At the moment the parachute is deployed the fairing is falling vertically.  Once the parachute is open and given some time to stabilize the fairing will be moving horizontally more than vertically by some glide ratio.  Perhaps something like 4:1 or 5:1 or so.  What you're seeing when the parafoil surges to the left and down in this video is the initiation of this forward motion.  Avoiding such a surge is one of the reasons that a sport parachute has a slider on it, by opening slowly this surge can be spread over a number of seconds and minimized (also, the l/d is low) (also helps to reduce deceleration loading).  A paraglider has a higher l/d and when falling vertically and suddenly opening a paraglider will surge forward and down quite dramatically, sometimes to the point that it gets under the pilot and the pilot can fall into it.
Title: Re: Fairing reuse
Post by: ThatOldJanxSpirit on 07/04/2019 05:53 pm
A secondary consideration is that the more ‘draggy’ fairing would better damp down fore / aft pendulum oscillations.

I'm not sure if you are referring specifically to the one forward surge of the parafoil shortly after opening or more generally, but if you're referring to that, its necessary.  At the moment the parachute is deployed the fairing is falling vertically.  Once the parachute is open and given some time to stabilize the fairing will be moving horizontally more than vertically by some glide ratio.  Perhaps something like 4:1 or 5:1 or so.  What you're seeing when the parafoil surges to the left and down in this video is the initiation of this forward motion.  Avoiding such a surge is one of the reasons that a sport parachute has a slider on it, by opening slowly this surge can be spread over a number of seconds and minimized (also, the l/d is low) (also helps to reduce deceleration loading).  A paraglider has a higher l/d and when falling vertically and suddenly opening a paraglider will surge forward and down quite dramatically, sometimes to the point that it gets under the pilot and the pilot can fall into it.

I was more thinking of any swing induced in the turbulent lower layers of the atmosphere. Just a thought that it may make it a bit more stable on approach.
Title: Re: Fairing reuse
Post by: butterwaffle on 07/04/2019 05:55 pm
Here’s part of what a fairing goes through to be recovered:

https://twitter.com/spacex/status/1146546495241371649

Quote
View from the fairing during the STP-2 mission; when the fairing returns to Earth, friction heats up particles in the atmosphere, which appear bright blue in the video

One thing that confuses me about the video... where is the payload? The fairing separation happens before the payload is deployed, but I didn't see anything stay with the second stage when the fairing separated. Any ideas?
Title: Re: Fairing reuse
Post by: Mandella on 07/04/2019 05:59 pm
For those without Twitter:

Edit: added the catch.


 - They land at the very beginning of the net, and at the center laterally. It seems it's not close to missing it at all and that on the contrary, they didn't use much of the margin they had. All things considered, that's a very good catch I think.



And that side catch supports the possibility of one boat two catches again. If they can have enough control to steer the fairings reliably into one half the net each time it would be no problem.
Title: Re: Fairing reuse
Post by: OxCartMark on 07/04/2019 07:08 pm
One thing that confuses me about the video... where is the payload?

Wow.  I think we're getting our first look onboard the Zuma launch.  And what I can tell you after looking at this video multiple times is that either Zuma is transparent / invisible or that they completely forgot to load Zuma onto the F9 which would explain how SpaceX had a successful launch to the correct orbit but Zuma wasn't there afterward.

In other news, yea, why are we not seeing a payload?  We're obviously looking from the nose down.
Title: Re: Fairing reuse
Post by: Silmfeanor on 07/04/2019 07:11 pm
One thing that confuses me about the video... where is the payload?

Wow.  I think we're getting our first look onboard the Zuma launch.  And what I can tell you after looking at this video multiple times is that either Zuma is transparent / invisible or that they completely forgot to load Zuma onto the F9 which would explain how SpaceX had a successful launch to the correct orbit but Zuma wasn't there afterward.

In other news, yea, why are we not seeing a payload?  We're obviously looking from the nose down.

look closer at the start. it's a fisheye lens, so distorted. it's there at the bottom.
Title: Re: Fairing reuse
Post by: woods170 on 07/04/2019 07:22 pm
One thing that confuses me about the video... where is the payload?

Wow.  I think we're getting our first look onboard the Zuma launch.  And what I can tell you after looking at this video multiple times is that either Zuma is transparent / invisible or that they completely forgot to load Zuma onto the F9 which would explain how SpaceX had a successful launch to the correct orbit but Zuma wasn't there afterward.

In other news, yea, why are we not seeing a payload?  We're obviously looking from the nose down.

look closer at the start. it's a fisheye lens, so distorted. it's there at the bottom.

butterwaffle and OxCartMark are clearly in need of new glasses  ;)
See screenshot below.

Title: Re: Fairing reuse
Post by: envy887 on 07/04/2019 08:53 pm
Ok so I have to throw this out there......

Do you guys think that an astronaut would survive the fall from space inside that fairing? Environment looks relatively benign (as far as reentry goes....).

Well, the question is how he gets there in the first place... but assuming he rides inside the payload bay and sticks somehow to the fairing during fairing separation and the fairing structurally survives the concentrated mass and the control computer can cope with the added mass, it might be survivable. All these assumptions aside (which are technical detais for this problem, really).. the g-loads might black him or her out or kill outright. I have no idea how fast the fairing decelerates. Probably fast.

My "bold" added above.  Lots of Velcro strapping you in by the fairing CG is obviously part of this solution. :)  I think inside the top conical fairings of FH side booster is a more interesting place for a ride along.

A side booster could be a much more interesting landing. At least in a fairing the splash is soft even if it misses the net.
Title: Re: Fairing reuse
Post by: FlattestEarth on 07/05/2019 08:28 am
Thoughts on the orientation of the fairing relative to the parachute. Mounting sideways makes good sense for touchdowns as it eliminates ‘slap down’ loads from nose high / nose low landings. A secondary consideration is that the more ‘draggy’ fairing would better damp down fore / aft pendulum oscillations.

So they did rotate the chute 90deg from previous orientation?
Title: Re: Fairing reuse
Post by: butterwaffle on 07/05/2019 03:35 pm
One thing that confuses me about the video... where is the payload?

Wow.  I think we're getting our first look onboard the Zuma launch.  And what I can tell you after looking at this video multiple times is that either Zuma is transparent / invisible or that they completely forgot to load Zuma onto the F9 which would explain how SpaceX had a successful launch to the correct orbit but Zuma wasn't there afterward.

In other news, yea, why are we not seeing a payload?  We're obviously looking from the nose down.

look closer at the start. it's a fisheye lens, so distorted. it's there at the bottom.

butterwaffle and OxCartMark are clearly in need of new glasses  ;)
See screenshot below.

I thought that was the payload adaptor mounting ring. Thanks.
Title: Re: Fairing reuse
Post by: speedevil on 07/05/2019 07:04 pm
One thing that confuses me about the video... where is the payload?

Wow.  I think we're getting our first look onboard the Zuma launch.  And what I can tell you after looking at this video multiple times is that either Zuma is transparent / invisible or that they completely forgot to load Zuma onto the F9 which would explain how SpaceX had a successful launch to the correct orbit but Zuma wasn't there afterward.

In other news, yea, why are we not seeing a payload?  We're obviously looking from the nose down.

look closer at the start. it's a fisheye lens, so distorted. it's there at the bottom.

I think it is likely this is TESS.
(https://i.imgur.com/8XUuF1Lm.jpg)
TESS was damn tiny, the front appears to be roughly right, with the bits outside the circle being folded panels and antenna.
Title: Re: Fairing reuse
Post by: stioks on 07/05/2019 07:30 pm
One thing that confuses me about the video... where is the payload?

Wow.  I think we're getting our first look onboard the Zuma launch.  And what I can tell you after looking at this video multiple times is that either Zuma is transparent / invisible or that they completely forgot to load Zuma onto the F9 which would explain how SpaceX had a successful launch to the correct orbit but Zuma wasn't there afterward.

In other news, yea, why are we not seeing a payload?  We're obviously looking from the nose down.

look closer at the start. it's a fisheye lens, so distorted. it's there at the bottom.

butterwaffle and OxCartMark are clearly in need of new glasses  ;)
See screenshot below.

This should be the top of STP 2 payload. Image from SpaceX site:
(https://www.spacex.com/sites/all/themes/spacex2012/images/stp/STP_Stills_DSX_1.jpg)
Title: Re: Fairing reuse
Post by: cscott on 07/05/2019 09:00 pm




I think it is likely this is TESS.
(https://i.imgur.com/8XUuF1Lm.jpg)
TESS was damn tiny, the front appears to be roughly right, with the bits outside the circle being folded panels and antenna.

Elon's tweet said this was the fairing from STP-2.
Title: Re: Fairing reuse
Post by: Comga on 07/05/2019 09:46 pm
From the STP-2 Updates thread
Video of fairing landing on the net: https://twitter.com/elonmusk/status/1146574336205058048 (https://twitter.com/elonmusk/status/1146574336205058048)
It does look like the fairing is moving "sideways" when it hits the net.
The caught fairing is not fully within the field of view of the camera. 
This suggests to me that it is near the outer limit of the expected landing position and the edge of the net.
Title: Re: Fairing reuse
Post by: FlattestEarth on 07/05/2019 11:48 pm

I think it is likely this is TESS.

TESS was damn tiny, the front appears to be roughly right, with the bits outside the circle being folded panels and antenna.

https://forum.nasaspaceflight.com/index.php?topic=30544.msg1273515#msg1273515
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 07/06/2019 09:35 am
Scott Manley’s take on the fairing recovery videos:

https://youtu.be/MRvO8D9TR08

Interesting what he says about camera set-up affecting visibility & colours of the ionised air.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 07/22/2019 06:09 am
Quote
Extended transcript: SpaceX CEO Elon Musk on putting boots on the moon and Mars
BY DAVID MORGAN
JULY 21, 2019 / 10:22 AM / CBS NEWS

https://www.cbsnews.com/news/extended-transcript-spacex-ceo-elon-musk-on-putting-boots-on-the-moon-and-mars/

Elon describes the “insane” fairing recovery process and then says:

Quote
And then the boat closes a data link with each fairing half. And the boat adjusts course automatically. And then the two just maneuver to touch each other. And we only just solved that in the last launch.
Title: Re: Fairing reuse
Post by: catdlr on 07/22/2019 06:21 am
Quote
Extended transcript: SpaceX CEO Elon Musk on putting boots on the moon and Mars
BY DAVID MORGAN
JULY 21, 2019 / 10:22 AM / CBS NEWS

https://www.cbsnews.com/news/extended-transcript-spacex-ceo-elon-musk-on-putting-boots-on-the-moon-and-mars/

Elon describes the “insane” fairing recovery process and then says:

Quote
And then the boat closes a data link with each fairing half. And the boat adjusts course automatically. And then the two just maneuver to touch each other. And we only just solved that in the last launch.

video
https://youtu.be/OPrb50ZDphc
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 07/23/2019 12:26 pm
Cross-posting; looks in very good shape after its swim:

https://twitter.com/lake_sea_mtns/status/1153638946515169280

Quote
Back in time, the Starlink fairing from F9 that launched in May 2019. Only shows minimal wear & ready for refurbishment.  #Spacex #Nasa #ElonMusk #Space @SpaceXUpdates @SpaceXFleet
Title: Re: Fairing reuse
Post by: jpo234 on 08/06/2019 04:35 pm
Close look at the thermal protection at the tip of the fairing:

(https://forum.nasaspaceflight.com/index.php?action=dlattach;topic=44162.0;attach=1575037;image)
Title: Re: Fairing reuse
Post by: The Vorlon on 08/06/2019 09:19 pm
I know I need new glasses, but what am I looking for?
Title: Re: Fairing reuse
Post by: intelati on 08/06/2019 09:21 pm
I know I need new glasses, but what am I looking for?

I don't see anything of particular note, but this is an interesting angle that we don't get to see very often
Title: Re: Fairing reuse
Post by: wannamoonbase on 08/07/2019 12:45 am
Excellent video of the fairing catch on Twitter.

So exciting to see this work twice in a row. Starlink just keeps getting cheaper.

The only question is how do they handle those pretty fairing graphics when it gets used on multiple flights?
Title: Re: Fairing reuse
Post by: AC in NC on 08/07/2019 12:54 am
The only question is how do they handle those pretty fairing graphics when it gets used on multiple flights?

ISTM if I didn't miss anything, there remains the question of how they catch two.  I recall lots of conjecture but no hints.
Title: Re: Fairing reuse
Post by: FlattestEarth on 08/07/2019 02:11 am
More than 40min between fairing jettison and catch?  How much of that is post chute deployment?
Title: Re: Fairing reuse
Post by: Rondaz on 08/07/2019 03:22 am
Watch SpaceX's droneship catch a rocket part that fell from space..

SpaceX is getting good at this.

BY JACKSON RYAN
AUGUST 6, 2019 6:28 PM PDT

https://www.cnet.com/news/watch-spacexs-droneship-catch-a-rocket-part-that-fell-from-space/?utm_source=reddit.com
Title: Re: Fairing reuse
Post by: jpo234 on 08/07/2019 06:21 am
I know I need new glasses, but what am I looking for?

The metal (stainless steel ?) tip is a fairly recent addition.
Title: Re: Fairing reuse
Post by: jee_c2 on 08/07/2019 08:06 am
So this time it was only one half of the fairing caught, right? (Grats for it! btw)
Title: Re: Fairing reuse
Post by: old_geez on 08/07/2019 08:13 am
They only “catch” one half, the other is fished out of the water
Title: Re: Fairing reuse
Post by: tyrred on 08/07/2019 08:23 am
Anyone have a link to the twitter video of yesterday's fairing catch?
Title: Re: Fairing reuse
Post by: niwax on 08/07/2019 08:39 am
They only “catch” one half, the other is fished out of the water

Here's an interesting thought: SpaceX has stated they are fine with flying wet fairings on Starlink. A long as they catch one on the boat and one in the water, they might still have enough to make pairs for almost all launches.
Title: Re: Fairing reuse
Post by: jpo234 on 08/07/2019 09:12 am
Anyone have a link to the twitter video of yesterday's fairing catch?

https://twitter.com/elonmusk/status/1158968745227780096
Title: Re: Fairing reuse
Post by: Johnnyhinbos on 08/07/2019 10:22 am
I know I need new glasses, but what am I looking for?

I don't see anything of particular note, but this is an interesting angle that we don't get to see very often
The tip of the fairing is clad in a metallic material as a TPS element (circled in green below). This is a relatively new addition and this shot shows it really well...
Title: Re: Fairing reuse
Post by: jpo234 on 08/07/2019 11:22 am
I know I need new glasses, but what am I looking for?

I don't see anything of particular note, but this is an interesting angle that we don't get to see very often
The tip of the fairing is clad in a metallic material as a TPS element (circled in green below). This is a relatively new addition and this shot shows it really well...

If I remember correctly, the first time we saw it was at the GPS III SV01 mission. At the time it looked black, so maybe they switched the material after their new found love for stainless steel:

(https://forum.nasaspaceflight.com/index.php?action=dlattach;topic=46962.0;attach=1535263;image)
Title: Re: Fairing reuse
Post by: scr00chy on 08/07/2019 11:29 am

If I remember correctly, the first time we saw it was at the GPS III SV01 mission.


Correct. Since then, it's been used on Nusantara Satu, Arabsat 6A, Starlink v0.9, STP-2 and now Amos-17. The fairing was recovered on all launches except GPS (ship was still in California) and Nusantara Satu (ship got damaged on her way to the recovery zone).
Title: Re: Fairing reuse
Post by: docmordrid on 08/08/2019 12:40 am
It'd be a hoot if they did a stainless steel fairing.
Title: Re: Fairing reuse
Post by: speedevil on 08/08/2019 01:44 am
It'd be a hoot if they did a stainless steel fairing.
At the reported thickness of ~5mm for SS, a 5.4m*12m fairing with 50% non-skin material as reinforcement would end up around 10 tons.
This would reduce payload by ~1.5 tons for F9, significantly less for FH.
Title: Re: Fairing reuse
Post by: Robotbeat on 08/08/2019 02:43 pm
It'd be a hoot if they did a stainless steel fairing.
Not a good fit. Fairings aren't pressurized, so you need good flexural stiffness. It's a good fit for carbon fiber or aluminum, but not a denser material like stainless steel, even if the specific strength may be similar (since you have to make the stainless thinner to have the same weight, and a thinner shell means easier to flex, all things being equal).
Title: Re: Fairing reuse
Post by: Okie_Steve on 08/08/2019 05:32 pm
Any particular reason a faring could not be presurized?
Title: Re: Fairing reuse
Post by: DistantTemple on 08/08/2019 05:40 pm
Any particular reason a faring could not be presurized?
AIUI fairings have a vent, to vent pressure as they ascend out of the atmosphere. Just by logic, retaining a higher than (local) atmospheric pressure, would result in a "sudden" pressure change when the fairing is jettisoned. This would be an added risk for the satellite manufacturer to mitigate against.
Title: Re: Fairing reuse
Post by: envy887 on 08/08/2019 07:31 pm
It'd be a hoot if they did a stainless steel fairing.
Not a good fit. Fairings aren't pressurized, so you need good flexural stiffness. It's a good fit for carbon fiber or aluminum, but not a denser material like stainless steel, even if the specific strength may be similar (since you have to make the stainless thinner to have the same weight, and a thinner shell means easier to flex, all things being equal).

Fairings also don't normally operate at extremely cold or hot temperatures, which is where stainless really beats aluminum and composites.
Title: Re: Fairing reuse
Post by: Kabloona on 08/08/2019 11:52 pm
It'd be a hoot if they did a stainless steel fairing.
At the reported thickness of ~5mm for SS, a 5.4m*12m fairing with 50% non-skin material as reinforcement would end up around 10 tons.
This would reduce payload by ~1.5 tons for F9, significantly less for FH.

See, that outokumpu stainless steel storage tank calculator...err, rocket fairing designer... really comes in handy.  :)

https://secure.outokumpu.com/steelfinder/Storage-Tank/Default.aspx
Title: Re: Fairing reuse
Post by: speedevil on 08/09/2019 12:09 am
It'd be a hoot if they did a stainless steel fairing.
At the reported thickness of ~5mm for SS, a 5.4m*12m fairing with 50% non-skin material as reinforcement would end up around 10 tons.
This would reduce payload by ~1.5 tons for F9, significantly less for FH.

See, that outokumpu stainless steel storage tank calculator...err, rocket fairing designer... really comes in handy.  :)

https://secure.outokumpu.com/steelfinder/Storage-Tank/Default.aspx
This does not work (I have admittedly not checked) for unpressurised large tanks exposed to moderately high external loadings from wind.

It is trivial if you pressurise them, but that does raise other issues.

This is why my original comment mentioned 'non-skin' - assuming ~50% of the total SS more than the skin goes into stringers and related structure.

The existing skin is CF of undefined thickness covering a 1" aluminium honeycomb core.
Title: Re: Fairing reuse
Post by: Kabloona on 08/09/2019 03:07 am
It'd be a hoot if they did a stainless steel fairing.
At the reported thickness of ~5mm for SS, a 5.4m*12m fairing with 50% non-skin material as reinforcement would end up around 10 tons.
This would reduce payload by ~1.5 tons for F9, significantly less for FH.

See, that outokumpu stainless steel storage tank calculator...err, rocket fairing designer... really comes in handy.  :)

https://secure.outokumpu.com/steelfinder/Storage-Tank/Default.aspx
This does not work (I have admittedly not checked) for unpressurised large tanks exposed to moderately high external loadings from wind.

It is trivial if you pressurise them, but that does raise other issues.

This is why my original comment mentioned 'non-skin' - assuming ~50% of the total SS more than the skin goes into stringers and related structure.

The existing skin is CF of undefined thickness covering a 1" aluminium honeycomb core.

I was attempting to inject some levity and evidently failed. Clearly the tank calculator would *not* have designed an adequate fairing.

But it would actually have helped do your stainless fairing weight calc. If you run your fairing dimensions through the calculator, and apply your 1.5 multiplier for stiffeners, you'll get pretty close to the 10 tons you figured (by hand, I assume).

So the tank calculator would have saved you a few steps in your weight estimate.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 08/09/2019 11:08 pm
Cross posting, 2 boats confirmed for full fairing reuse:

Confirmed by Elon:

twitter.com/erdayastronaut/status/1159962159155228672

Quote
@elonmusk is Go Ms. Chief the sister to Go Ms. Tree? 🤔 gonna get both halves soon? 🤔

https://twitter.com/elonmusk/status/1159963432466075648

Quote
Yup
Title: Re: Fairing reuse
Post by: Stefan.Christoff.19 on 08/12/2019 02:44 pm
Trying to figure out if they have enough fairings for a first reuse got me wondering if fairing halves are identical. Meaning is there a "Left" and a "Right" halves that only slot in that place. If they are not side specific then they have the two necessary for a first reuse flight. I did a lazy search in the thread, and didn't find anything on this.
Also what exactly needs to be refurbished on the fairings? Is the padding specific to payload?
Title: Re: Fairing reuse
Post by: Lar on 08/12/2019 04:19 pm
Trying to figure out if they have enough fairings for a first reuse got me wondering if fairing halves are identical. Meaning is there a "Left" and a "Right" halves that only slot in that place. If they are not side specific then they have the two necessary for a first reuse flight. I did a lazy search in the thread, and didn't find anything on this.
Also what exactly needs to be refurbished on the fairings? Is the padding specific to payload?
Upthread (or somewhere) I was wondering this myself, I posited that all the "pushing" at separation time comes from one half, the "active" one, and that if they switched to half and half, or made this pusher assembly easily swappable, they could either lose the active/passive designation (both halves become identical) or switch a fairing from one to the other quickly.
Title: Re: Fairing reuse
Post by: Cheapchips on 08/13/2019 02:31 pm
I wonder what the thresholds on weather/sea conditions are for fairing capture? This 2nd successful attempt looked to be in fairly calm conditions, although a little hard to tell at night.  I can see them holding Starlink launches for favorable fairing recovery conditions. 
Title: Re: Fairing reuse
Post by: Rondaz on 08/13/2019 09:23 pm
@timothytchen1 on twitter: "Talked to RUAG guy at the Small Sat Conference, he confirmed they signed an agreement with SpaceX. RUAG will be producing fairing out of the Decatur facility."

https://twitter.com/timothytchen1/status/1161261562713137153
Title: Re: Fairing reuse
Post by: hplan on 08/13/2019 09:34 pm
This was in response to the question of whether SpaceX will produce a larger fairing.
Title: Re: Fairing reuse
Post by: Lar on 08/13/2019 09:38 pm
I heard somewhere "the Decatur facility" is inside a ULA building.

I have to wonder if SpaceX would apply all the recovery gear to these larger ones. I think it worth a try.
Title: Re: Fairing reuse
Post by: wannamoonbase on 08/13/2019 10:02 pm
I heard somewhere "the Decatur facility" is inside a ULA building.

I have to wonder if SpaceX would apply all the recovery gear to these larger ones. I think it worth a try.

I doubt it. 

The fairings they would contract out would be special DOD launches. So the volume will be low and DOD may require new hardware.
Title: Re: Fairing reuse
Post by: DistantTemple on 08/13/2019 10:17 pm
I heard somewhere "the Decatur facility" is inside a ULA building.

I have to wonder if SpaceX would apply all the recovery gear to these larger ones. I think it worth a try.

I doubt it. 

The fairings they would contract out would be special DOD launches. So the volume will be low and DOD may require new hardware.
ISTM that since SX is likely to be significantly cheaper than the competition, there should be no problem with charging the full purchase price (+markup) of the fairing to the DOD, or including it in the agreement, and still remaining by far the most cost effective.
Will Dectur be able to use their existing tooling? Will they have to adapt how it fixes to SX's 2nd stage,or can SX make an adaptor, or adapt the 2nd stage so it will fit to an "off the shelf" version?
I assume we don't know, but avoiding making a new mold/former is the reason SX is not making its own.
Title: Re: Fairing reuse
Post by: Barley on 08/14/2019 12:42 am
I heard somewhere "the Decatur facility" is inside a ULA building.

I have to wonder if SpaceX would apply all the recovery gear to these larger ones. I think it worth a try.

I doubt it. 

The fairings they would contract out would be special DOD launches. So the volume will be low and DOD may require new hardware.

Reuse wouldn't have to be on a DOD mission.
Title: Re: Fairing reuse
Post by: gongora on 08/14/2019 03:25 am
I have to wonder if SpaceX would apply all the recovery gear to these larger ones. I think it worth a try.

The big RUAG fairings seem a bit different structurally than what SpaceX is currently using.  The SpaceX fairings are pretty stiff and strong to support horizontal integration.  The big RUAG fairings are used with vertical integration and seem flimsier (and probably lighter).  Not sure the RUAG fairing would be as easy to recover. 
Title: Re: Fairing reuse
Post by: Rismagi on 08/14/2019 04:58 am
RUAG have done some preliminary work on fairing reusability, which they presented on IAC-2016.

https://twitter.com/ruag_group/status/723518979373830144?lang=en (https://twitter.com/ruag_group/status/723518979373830144?lang=en)

https://www.teslarati.com/spacex-mr-steven-port-return-falcon-fairing-catch-uncertainty/ruag-fairing-recovery-analysis-1/ (https://www.teslarati.com/spacex-mr-steven-port-return-falcon-fairing-catch-uncertainty/ruag-fairing-recovery-analysis-1/)
Title: Re: Fairing reuse
Post by: Coastal Ron on 08/14/2019 05:43 am
I heard somewhere "the Decatur facility" is inside a ULA building.

I have to wonder if SpaceX would apply all the recovery gear to these larger ones. I think it worth a try.

It could be in a building on the ULA Decatur factory grounds that they lease to RUAG - companies usually like to have liability issues clearly defined, which would include (oddly enough) at what point the ownership of the fairings transfers over when they move it from the RUAG building to a ULA building at the same facility. And if they have a separate building then building product for other companies would be easier.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 08/14/2019 09:21 am
I have to wonder if SpaceX would apply all the recovery gear to these larger ones. I think it worth a try.

The big RUAG fairings seem a bit different structurally than what SpaceX is currently using.  The SpaceX fairings are pretty stiff and strong to support horizontal integration.  The big RUAG fairings are used with vertical integration and seem flimsier (and probably lighter).  Not sure the RUAG fairing would be as easy to recover.

Maybe RUAG would do a modified fairing design for SpaceX? Starlink launches could benefit from a larger fairing so I think SpaceX would want to reuse to minimise costs. Indeed the larger fairing may make sense even without DoD? (although clearly any available external funding is welcome)
Title: Re: Fairing reuse
Post by: speedevil on 08/14/2019 12:01 pm
I have to wonder if SpaceX would apply all the recovery gear to these larger ones. I think it worth a try.

The big RUAG fairings seem a bit different structurally than what SpaceX is currently using.  The SpaceX fairings are pretty stiff and strong to support horizontal integration.  The big RUAG fairings are used with vertical integration and seem flimsier (and probably lighter).  Not sure the RUAG fairing would be as easy to recover.

Maybe RUAG would do a modified fairing design for SpaceX? Starlink launches could benefit from a larger fairing so I think SpaceX would want to reuse to minimise costs. Indeed the larger fairing may make sense even without DoD? (although clearly any available external funding is welcome)
Elon has stated that making the existing fairing longer is almost trivial.
Title: Re: Fairing reuse
Post by: DistantTemple on 08/14/2019 12:14 pm
I have to wonder if SpaceX would apply all the recovery gear to these larger ones. I think it worth a try.

The big RUAG fairings seem a bit different structurally than what SpaceX is currently using.  The SpaceX fairings are pretty stiff and strong to support horizontal integration.  The big RUAG fairings are used with vertical integration and seem flimsier (and probably lighter).  Not sure the RUAG fairing would be as easy to recover.
Maybe RUAG would do a modified fairing design for SpaceX? Starlink launches could benefit from a larger fairing so I think SpaceX would want to reuse to minimise costs. Indeed the larger fairing may make sense even without DoD? (although clearly any available external funding is welcome)
Elon has stated that making the existing fairing longer is almost trivial.
I'm sure the diameter is key point for DOD contracts, and thats the reason RUAG is involved, and SX appeared not keen to make its own verson for potentially 3 launches. Now RUAG appears to be thinking seriously of re-usability!  Length alone is not the solution to the DOD  contract problem.
Title: Re: Fairing reuse
Post by: envy887 on 08/14/2019 01:23 pm
I have to wonder if SpaceX would apply all the recovery gear to these larger ones. I think it worth a try.

The big RUAG fairings seem a bit different structurally than what SpaceX is currently using.  The SpaceX fairings are pretty stiff and strong to support horizontal integration.  The big RUAG fairings are used with vertical integration and seem flimsier (and probably lighter).  Not sure the RUAG fairing would be as easy to recover.
Maybe RUAG would do a modified fairing design for SpaceX? Starlink launches could benefit from a larger fairing so I think SpaceX would want to reuse to minimise costs. Indeed the larger fairing may make sense even without DoD? (although clearly any available external funding is welcome)
Elon has stated that making the existing fairing longer is almost trivial.
I'm sure the diameter is key point for DOD contracts, and thats the reason RUAG is involved, and SX appeared not keen to make its own verson for potentially 3 launches. Now RUAG appears to be thinking seriously of re-usability!  Length alone is not the solution to the DOD  contract problem.

Why? SpaceX's existing fairing already meets the EELV diameter requirements, and RUAG's fairing is only a few cm larger in diameter.
Title: Re: Fairing reuse
Post by: speedevil on 08/14/2019 02:15 pm
I have to wonder if SpaceX would apply all the recovery gear to these larger ones. I think it worth a try.

The big RUAG fairings seem a bit different structurally than what SpaceX is currently using.  The SpaceX fairings are pretty stiff and strong to support horizontal integration.  The big RUAG fairings are used with vertical integration and seem flimsier (and probably lighter).  Not sure the RUAG fairing would be as easy to recover.
Maybe RUAG would do a modified fairing design for SpaceX? Starlink launches could benefit from a larger fairing so I think SpaceX would want to reuse to minimise costs. Indeed the larger fairing may make sense even without DoD? (although clearly any available external funding is welcome)
Elon has stated that making the existing fairing longer is almost trivial.
I'm sure the diameter is key point for DOD contracts, and thats the reason RUAG is involved, and SX appeared not keen to make its own verson for potentially 3 launches. Now RUAG appears to be thinking seriously of re-usability!  Length alone is not the solution to the DOD  contract problem.

To be clearer - if the existing fairing can be easily made longer - the cost sharing assumed for Starlink being able to pack on more birds with a RUAG fairing (on heavy at least) is questionable.
Title: Re: Fairing reuse
Post by: FlattestEarth on 08/15/2019 08:33 am
@timothytchen1 on twitter: "Talked to RUAG guy at the Small Sat Conference, he confirmed they signed an agreement with SpaceX. RUAG will be producing fairing out of the Decatur facility."

https://twitter.com/timothytchen1/status/1161261562713137153

https://twitter.com/timothytchen1/status/1161666418649133056

 also Tory Bruno said "no." on the Reddit thread
Title: Re: Fairing reuse
Post by: Robotbeat on 08/17/2019 03:43 am
RUAG have done some preliminary work on fairing reusability, which they presented on IAC-2016.

https://twitter.com/ruag_group/status/723518979373830144?lang=en (https://twitter.com/ruag_group/status/723518979373830144?lang=en)

https://www.teslarati.com/spacex-mr-steven-port-return-falcon-fairing-catch-uncertainty/ruag-fairing-recovery-analysis-1/ (https://www.teslarati.com/spacex-mr-steven-port-return-falcon-fairing-catch-uncertainty/ruag-fairing-recovery-analysis-1/)
Now that's interesting. I either forgot that or didn't know about it. Good spot!
Title: Re: Fairing reuse
Post by: lonestriker on 08/17/2019 04:17 am
RUAG have done some preliminary work on fairing reusability, which they presented on IAC-2016.

https://twitter.com/ruag_group/status/723518979373830144?lang=en (https://twitter.com/ruag_group/status/723518979373830144?lang=en)

https://www.teslarati.com/spacex-mr-steven-port-return-falcon-fairing-catch-uncertainty/ruag-fairing-recovery-analysis-1/ (https://www.teslarati.com/spacex-mr-steven-port-return-falcon-fairing-catch-uncertainty/ruag-fairing-recovery-analysis-1/)
Now that's interesting. I either forgot that or didn't know about it. Good spot!

I remember when this was mentioned years ago.  Haven't heard anything since.

I'd put this announcement in the same group as ULA's "SMART" reuse for engines.  RUAG might be able to do air drop tests from helicopters, but that's a far cry from reentering.  Plus the chute they used in the Tweeted Photoshop isn't even steerable.  So it's Powerpoint technology and not a serious program AFAICS.

Title: Re: Fairing reuse
Post by: Lar on 08/17/2019 04:58 am
I remember when this was mentioned years ago.  Haven't heard anything since.

I'd put this announcement in the same group as ULA's "SMART" reuse for engines.  RUAG might be able to do air drop tests from helicopters, but that's a far cry from reentering.  Plus the chute they used in the Tweeted Photoshop isn't even steerable.  So it's Powerpoint technology and not a serious program AFAICS.
One wonders if SpaceX would consider transferring tech to RUAG for their recovery method. Probably not but it would be cool. Because I definitely could see SpaceX reusing longer fairings on non DoD missions (DoD insistence on new won't last forever,,, it will eventually be seen as silly)

So even if they don't *transfer* the tech they may use it anyway to give it a try? What have they got to lose. (counter argument, unlike booster reuse there is some potential for payload damage if a fairing tries to deploy chutes prematurely or whatever)
Title: Re: Fairing reuse
Post by: Semmel on 08/17/2019 05:12 am
I wouldn't like Spacex to transfer fairing recovery tech. Then they could pull the same trick as ULA to deny fairing recovery usage of other providers. And that would be counter productive in the long run. I want all the launch system providers to have recoverable fairings. Better let them develop it on their own and provide the option to all customers.
Title: Re: Fairing reuse
Post by: wannamoonbase on 08/17/2019 02:12 pm
I wouldn't like Spacex to transfer fairing recovery tech. Then they could pull the same trick as ULA to deny fairing recovery usage of other providers. And that would be counter productive in the long run. I want all the launch system providers to have recoverable fairings. Better let them develop it on their own and provide the option to all customers.

Fairing reuse, like other reuse technology, makes sense at higher flight rates.  Other US launch providers don’t have high flight rates.  So maybe it doesn’t make sense for others.

It will be interesting to see who follows, when and how long it takes them now that the way has been shown.

By the time Blue Origin or another company recovers their first booster or a fairing SpaceX maybe waving from the moon.
Title: Re: Fairing reuse
Post by: ZachS09 on 08/19/2019 01:57 am
I was thinking about something:

Is there such thing as pushing the limit of fairing recovery similar to the first stage booster going through the hottest reentry during the drone ship landing profile?

I'm talking about using up every bit of the heat protection tip during a certain mission.
Title: Re: Fairing reuse
Post by: Eerie on 08/19/2019 05:01 am
I was thinking about something:

Is there such thing as pushing the limit of fairing recovery similar to the first stage booster going through the hottest reentry during the drone ship landing profile?

I'm talking about using up every bit of the heat protection tip during a certain mission.

This makes no sense. You want to drop the fairings as soon as possible, they eat into the payload.
Title: Re: Fairing reuse
Post by: Rismagi on 08/19/2019 05:48 am
Plus the chute they used in the Tweeted Photoshop isn't even steerable.  So it's Powerpoint technology and not a serious program AFAICS.

Powerpoint it is. As for non-steerable... From what I see, they considered three options:

* Splashdown, parafoil (60 points)
* Net capture, parafoil (43 points)
* Mid-air capture, parachute (45 points)

Tweeted picture is probably about the third one, I guess. Similar to Rocket Lab reuse concept.

Interestingly, back in 2015, SpaceX considered doing mid-air retrieval of fairings too.

L2: SpaceX Fairing Recovery Overview https://forum.nasaspaceflight.com/index.php?topic=37066.0 (https://forum.nasaspaceflight.com/index.php?topic=37066.0)
Title: Re: Fairing reuse
Post by: OTV Booster on 08/19/2019 10:23 pm
I was thinking about something:

Is there such thing as pushing the limit of fairing recovery similar to the first stage booster going through the hottest reentry during the drone ship landing profile?

I'm talking about using up every bit of the heat protection tip during a certain mission.

Yes they do want to drop it as soon as possible but on some launched they grab altitude as fast as they can and on some they pitch over early on.

What follows is conjecture.

In either case they probably drop the fairing at the same altitude but if they pitch over early they have to cut through more air before they get to drop altitude and it probably gets hotter. Only a guess.

I doubt there’s any difference by the time it gets back to sea level but have no clue how fast it cools down. The heating from the drop itself probably overwhelms the heating from the climb. Again, speculation only.

Phil
Title: Re: Fairing reuse
Post by: Barley on 08/20/2019 07:50 pm
Looking at a limited number of launches I'd conjecture they drop the fairing in a fixed sequence as part of second stage separation.  Any counter examples?

Probably not optimal from launch mass perspective, but it would mean you don't have to model wildly different events and tweak the control rules.  If the difference between optimal and what they do is not large it may not be worth changing, or at least not worth changing yet.

In particular comparing the altitude and speed for fairing separation on F9 and FH suggests that aerodynamically FH might be able to drop the fairing before MECO.
.
Title: Re: Fairing reuse
Post by: AC in NC on 08/20/2019 08:30 pm
Looking at a limited number of launches I'd conjecture they drop the fairing in a fixed sequence as part of second stage separation.  Any counter examples?

IIRC .... It's been explicitly stated that Fairing is dropped based on a measurement (pressure?).    Based on that ISTM there is only downside from dropping the Fairing after the ideal point, and it's not clear to me that any lower trajectory than nominal provides any better value versus the harder work of going higher faster.

So to the OP question raised, I don't think there's much advantage to be gained from pushing father with the fairing in the same way that pushing farther with a core to be recovered does.
Title: Re: Fairing reuse
Post by: Stan-1967 on 08/20/2019 09:13 pm
IIRC .... It's been explicitly stated that Fairing is dropped based on a measurement (pressure?).    Based on that ISTM there is only downside from dropping the Fairing after the ideal point, and it's not clear to me that any lower trajectory than nominal provides any better value versus the harder work of going higher faster.

Yes, F9 users guide ( 2019 revision, section 4.3.9) says the fairing is deployed when aerothermal heating drops below 1135 W/m^2.  Deviation from this optimum will affect vehicle performance, & also have implications for the payload.
Title: Re: Fairing reuse
Post by: speedevil on 08/21/2019 01:45 am
IIRC .... It's been explicitly stated that Fairing is dropped based on a measurement (pressure?).    Based on that ISTM there is only downside from dropping the Fairing after the ideal point, and it's not clear to me that any lower trajectory than nominal provides any better value versus the harder work of going higher faster.

Yes, F9 users guide ( 2019 revision, section 4.3.9) says the fairing is deployed when aerothermal heating drops below 1135 W/m^2.  Deviation from this optimum will affect vehicle performance, & also have implications for the payload.

At the point the heating falls to that level, the aerodynamic drag of the fairing and rocket is almost precisely zero, so should not of itself change vehicle performance other than the fairing being shed.
Title: Re: Fairing reuse
Post by: Robotbeat on 08/22/2019 01:19 am
IIRC .... It's been explicitly stated that Fairing is dropped based on a measurement (pressure?).    Based on that ISTM there is only downside from dropping the Fairing after the ideal point, and it's not clear to me that any lower trajectory than nominal provides any better value versus the harder work of going higher faster.

Yes, F9 users guide ( 2019 revision, section 4.3.9) says the fairing is deployed when aerothermal heating drops below 1135 W/m^2.  Deviation from this optimum will affect vehicle performance, & also have implications for the payload.

At the point the heating falls to that level, the aerodynamic drag of the fairing and rocket is almost precisely zero, so should not of itself change vehicle performance other than the fairing being shed.
Yeah, the impact on vehicle performance will be that holding on to it longer will reduce performance.
Title: Re: Fairing reuse
Post by: OTV Booster on 08/30/2019 03:36 am
IIRC .... It's been explicitly stated that Fairing is dropped based on a measurement (pressure?).    Based on that ISTM there is only downside from dropping the Fairing after the ideal point, and it's not clear to me that any lower trajectory than nominal provides any better value versus the harder work of going higher faster.

Yes, F9 users guide ( 2019 revision, section 4.3.9) says the fairing is deployed when aerothermal heating drops below 1135 W/m^2.  Deviation from this optimum will affect vehicle performance, & also have implications for the payload.

At the point the heating falls to that level, the aerodynamic drag of the fairing and rocket is almost precisely zero, so should not of itself change vehicle performance other than the fairing being shed.
Yeah, the impact on vehicle performance will be that holding on to it longer will reduce performance.

This got me thinking. Do they have a customary height for ditching the fairing, do they model atmospherics and decide ahead of time or do they measure atmospheric density real time and decide on the fly?  The atmosphere changes a lot between solar max & min. CME’s play hob if they hit. My guess is model, but no real knowledge.

Phil
Title: Re: Fairing reuse
Post by: intelati on 08/30/2019 08:00 am
IIRC .... It's been explicitly stated that Fairing is dropped based on a measurement (pressure?).    Based on that ISTM there is only downside from dropping the Fairing after the ideal point, and it's not clear to me that any lower trajectory than nominal provides any better value versus the harder work of going higher faster.

Yes, F9 users guide ( 2019 revision, section 4.3.9) says the fairing is deployed when aerothermal heating drops below 1135 W/m^2.  Deviation from this optimum will affect vehicle performance, & also have implications for the payload.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 11/05/2019 05:40 pm
 :D

https://twitter.com/SpaceX/status/1191779329467748353 (https://twitter.com/SpaceX/status/1191779329467748353)

Quote from: SpaceX
The fairing supporting this mission previously flew on Falcon Heavy’s Arabsat-6A mission
Title: Re: Fairing reuse
Post by: hplan on 11/06/2019 02:23 pm
Quote from: SpaceX
The fairing supporting this mission previously flew on Falcon Heavy’s Arabsat-6A mission

Will this be the first reuse of a fairing? By SpaceX only, or by any orbital rocket launch firm?
Title: Re: Fairing reuse
Post by: wannamoonbase on 11/06/2019 02:46 pm

Quote from: SpaceX
The fairing supporting this mission previously flew on Falcon Heavy’s Arabsat-6A mission

Will this be the first reuse of a fairing? By SpaceX only, or by any orbital rocket launch firm?

[/quote]

Yes, there are multiple stories saying this is the first reuse of a fairing.

Pretty cool and they've really come a long way on developing this capability.

To have a vehicle with the capability of a F9 and only have the US expended is such a huge accomplishment.
Title: Re: Fairing reuse
Post by: Eric Hedman on 11/06/2019 02:52 pm
Does anyone know if Blue Origin, NGIS or ULA have any plans for fairing reuse?  I'm wondering if this will become an industry standard practice in the coming years.
Title: Re: Fairing reuse
Post by: scr00chy on 11/06/2019 03:04 pm
I remember reading something about RUAG looking into fairing reuse but don't know if it's something they're actively working on.

AFAIK, Blue Origin didn't talk publicly about fairing reuse but I'd be surprised if they weren't at least internally exploring the possibility of fairing reuse. Then again, they're fairing is huge so I'm not sure if the SpaceX's recovery approach would be possible here. If not, Blue Origin would have to come up with their own unique solution which would be much harder obviously.

As for the other companies, I doubt they'd be considering fairing reuse before seriously working towards booster reuse which represents much larger portion of the overall cost.
Title: Re: Fairing reuse
Post by: wannamoonbase on 11/06/2019 08:23 pm
I remember reading something about RUAG looking into fairing reuse but don't know if it's something they're actively working on.

AFAIK, Blue Origin didn't talk publicly about fairing reuse but I'd be surprised if they weren't at least internally exploring the possibility of fairing reuse. Then again, they're fairing is huge so I'm not sure if the SpaceX's recovery approach would be possible here. If not, Blue Origin would have to come up with their own unique solution which would be much harder obviously.

As for the other companies, I doubt they'd be considering fairing reuse before seriously working towards booster reuse which represents much larger portion of the overall cost.

If BO's is that much bigger than it's that much more valuable too.  But at the rate that BO develops capabilities.....
Title: Re: Fairing reuse
Post by: jee_c2 on 11/14/2019 09:42 am
Unfortunately at the last launch, sea conditions made fairing catch impossible practically. Even though, do we have some data (reported from the launch) if the now reused fairing could have been used one more time (the 3rd time), remained usable?
Title: Re: Fairing reuse
Post by: docmordrid on 11/14/2019 10:41 am
ISTM this fairing issue  becomes academic once the Starship "Chomper" is operational.
Title: Re: Fairing reuse
Post by: jeffkruse on 11/18/2019 05:20 pm
Is/if Space X is putting all their eggs in one basket with Starship does it make sense to continue to develop fairing recovery?  If those resources were put towards Starship wouldn't that have been better?  How long will Falcon 9 fly when Starship is flying?
Title: Re: Fairing reuse
Post by: AC in NC on 11/18/2019 05:25 pm
Is/if Space X is putting all their eggs in one basket with Starship does it make sense to continue to develop fairing recovery?  If those resources were put towards Starship wouldn't that have been better?  How long will Falcon 9 fly when Starship is flying?

I was thinking on this relative to the "Plan B if Starship Fails" topic, particularly how SX might leverage a SS that doesn't completely meet expectations.

It might well fly much longer than you would normally think for backup or noise reasons.
Title: Re: Fairing reuse
Post by: whitelancer64 on 11/18/2019 05:27 pm
Is/if Space X is putting all their eggs in one basket with Starship does it make sense to continue to develop fairing recovery?  If those resources were put towards Starship wouldn't that have been better?  How long will Falcon 9 fly when Starship is flying?

Yes, because it still saves money / reduces cost in the meanwhile.

Falcon 9 will continue to fly at least for the commercial crew program for ISS crew rotations. They've got Falcon 9 launch contracts out to 2023, some of which may migrate to Starship/SH. Military / NRO launches likely won't, though.
Title: Re: Fairing reuse
Post by: jeffkruse on 11/18/2019 05:34 pm
I'm just speaking about fairing recovery.  Recovery development takes time and money.  Since fairing recovery is moving forward it looks like Space X is doing that just in case Starship takes much longer than they expect.  I just wish we could see at least 50% of the company focused on Starship.  My mind is blown already by the progress they have made.  I can't image what could happen if more resources were put into Starship.
Title: Re: Fairing reuse
Post by: Billium on 11/18/2019 05:35 pm
Is/if Space X is putting all their eggs in one basket with Starship does it make sense to continue to develop fairing recovery?  If those resources were put towards Starship wouldn't that have been better?  How long will Falcon 9 fly when Starship is flying?

Yes, because it still saves money / reduces cost in the meanwhile.

Falcon 9 will continue to fly at least for the commercial crew program for ISS crew rotations. They've got Falcon 9 launch contracts out to 2023, some of which may migrate to Starship/SH. Military / NRO launches likely won't, though.

Additionally, I’m not sure what the current fairing production rate is, but SpaceX may need to reuse fairings in order to launch all the payloads, especially all of the Starlink payloads they need to launch next year.
Title: Re: Fairing reuse
Post by: whitelancer64 on 11/18/2019 05:37 pm
I'm just speaking about fairing recovery.  Recovery development takes time and money.  Since fairing recovery is moving forward it looks like Space X is doing that just in case Starship takes much longer than they expect.  I just wish we could see at least 50% of the company focused on Starship.  My mind is blown already by the progress they have made.  I can't image what could happen if more resources were put into Starship.

Fairing recovery is worthwhile in and of itself. They cost ~$3 million per fairing half. Recovery saves way more money than it costs.
Title: Re: Fairing reuse
Post by: SteveU on 11/18/2019 06:08 pm
I'm just speaking about fairing recovery.  Recovery development takes time and money.  Since fairing recovery is moving forward it looks like Space X is doing that just in case Starship takes much longer than they expect.  I just wish we could see at least 50% of the company focused on Starship.  My mind is blown already by the progress they have made.  I can't image what could happen if more resources were put into Starship.

Fairing recovery is worthwhile in and of itself. They cost ~$3 million per fairing half. Recovery saves way more money than it costs.
Worth it even if they only use recovered fairings on Starlink launches.
Title: Re: Fairing reuse
Post by: wannamoonbase on 12/17/2019 03:40 am
Fairing reuse appears to be very difficult. 

Starting to wonder if they can get this dialed in.
Title: Re: Fairing reuse
Post by: Mandella on 12/17/2019 04:40 am
Fairing reuse appears to be very difficult. 

Starting to wonder if they can get this dialed in.

I think you mean fairing catching. They've managed to reuse two that they had to fish out of the water -- the big difference seems to be the amount of refurbishment necessary.

But I agree that the jury is still not in on whether it is economical or practical in the long run.
Title: Re: Fairing reuse
Post by: wannamoonbase on 12/17/2019 04:52 pm
Fairing reuse appears to be very difficult. 

Starting to wonder if they can get this dialed in.

I think you mean fairing catching. They've managed to reuse two that they had to fish out of the water -- the big difference seems to be the amount of refurbishment necessary.

But I agree that the jury is still not in on whether it is economical or practical in the long run.

Fair enough on catching. 

With the usual manifest plus 24 Starlink launches next year I'm sure we'll see how they do with reuse.
Title: Re: Fairing reuse
Post by: ZachS09 on 02/07/2020 01:23 pm
When will they start reusing the passive fairings that Ms. Tree caught? Obviously, they have to take some time refurbishing the active fairings because they landed in the ocean, but they should be able to refly the passive ones ASAP.
Title: Re: Fairing reuse
Post by: wannamoonbase on 02/07/2020 02:18 pm
When will they start reusing the passive fairings that Ms. Tree caught? Obviously, they have to take some time refurbishing the active fairings because they landed in the ocean, but they should be able to refly the passive ones ASAP.

I'd expect they continue with using them on Starlink missions until the industry is comfortable. 

Plus, there really aren't that many commercial missions on the manifest.  Lots of DOD and NASA flights and they don't take risks until others do.

It's really impressive they have figured this out. 
Title: Re: Fairing reuse
Post by: eeergo on 02/21/2020 08:23 am
https://twitter.com/julia_bergeron/status/1230603880301518848

Both fairings unusable :(
Title: Re: Fairing reuse
Post by: matthewkantar on 02/21/2020 01:57 pm
Seems like the fairing halves would have to have hit the masts on the catch boats to come home with damage like that? Two for two would be really bad luck.
Title: Re: Fairing reuse
Post by: anof on 02/21/2020 02:51 pm
Seems like the fairing halves would have to have hit the masts on the catch boats to come home with damage like that? Two for two would be really bad luck.

They might have been in the water awhile before being picked up and wave action broke them.
Title: Re: Fairing reuse
Post by: matthewkantar on 02/21/2020 06:40 pm
Seems like the fairing halves would have to have hit the masts on the catch boats to come home with damage like that? Two for two would be really bad luck.

They might have been in the water awhile before being picked up and wave action broke them.

The damage in this image from Julia Bergeron does not look like wave damage to me, looks like an impact. We have seen plenty of fairings that came back from water landing, I don't recall damage matching this.
Title: Re: Fairing reuse
Post by: Bananas_on_Mars on 02/21/2020 07:47 pm
Seems like at least for the fairing on Ms. Tree impact seems likely...


„Looks like Ms. Tree's fairing half's parachute got stuck on the net.“

https://twitter.com/kyle_m_photo/status/1230946876972728320?s=21
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 03/10/2020 06:12 pm
https://twitter.com/joroulette/status/1237446193644539905

Quote
Shotwell: We are largely done iterating Falcon 9. We're still trying to nail payload fairing recovery — we've learned we could scoop it out of the water and re-fly it, which we've done. Similar remarks as Elon's yesterday:
Title: Re: Fairing reuse
Post by: wannamoonbase on 03/18/2020 10:30 pm
Despite today's booster problem.  It was excellent to see a fairing fly it's second flight and again be pulled from the water intact.

Very encouraging to see happen.

Has anyone seen a limit on how many times they expect to be able to reuse a fairing?
Title: Re: Fairing reuse
Post by: john smith 19 on 03/19/2020 03:59 pm
Just a reminder

Starlink full deployment is c12000 satellites.

That's two hundred F9 launches.

Obviously they should be able to start generating long before that (and they've already got F9 booster re-use and fairing recovery more or less worked out) but those pesky F9 upper stages are not good for a startup balance sheet, which is what Starlink is.

Remember Musks comment about being "The first LEO comms constellation to not go bankrupt."

Flying all your birds on a fully reusable vehicle should make that a lot easier.

Regarding the thread topic this is the first ever  attempt to fly a fairing for a second time (ever).

The first ever F9 booster recovery to a ship went considerably worse.  :(

Also F9 booster recovery was first tried after Grasshopper flew 10s (100s?) of test flights. I've not heard of anything like that (some kind of fairing ejection simulator) being used to practice fairing recovery.

I don't know wheather either part of this fairing will fly again (or maybe you can interchange halves and one side will, the other side won't) but I am sure it won't be the last attempt by SX to do so.

Title: Re: Fairing reuse
Post by: Mandella on 03/19/2020 05:19 pm


Regarding the thread topic this is the first ever  attempt to fly a fairing for a second time (ever).


A minor correction, unless I am misunderstanding and you are just speaking in general, but the first fairing reuse was back in November of last year for a Starlink launch.

https://spaceflightnow.com/2019/11/05/spacex-to-reuse-payload-fairing-for-first-time-on-nov-11-launch/
Title: Re: Fairing reuse
Post by: su27k on 03/20/2020 04:16 am
Also F9 booster recovery was first tried after Grasshopper flew 10s (100s?) of test flights. I've not heard of anything like that (some kind of fairing ejection simulator) being used to practice fairing recovery.

They did test drops of faring from helicopters: https://www.teslarati.com/spacex-mr-steven-falcon-fairing-catch-practice/
Title: Re: Fairing reuse
Post by: wannamoonbase on 03/20/2020 12:58 pm
Also F9 booster recovery was first tried after Grasshopper flew 10s (100s?) of test flights. I've not heard of anything like that (some kind of fairing ejection simulator) being used to practice fairing recovery.

They did test drops of faring from helicopters: https://www.teslarati.com/spacex-mr-steven-falcon-fairing-catch-practice/

True, they spent considerable time doing tests on the west coast during the surge of launches out there. 

I love how SpaceX has used existing hardware and opportunities paid for by customers. 

F9 Booster and fairing reuse are excellent examples.
Title: Re: Fairing reuse
Post by: john smith 19 on 03/20/2020 07:45 pm
Also F9 booster recovery was first tried after Grasshopper flew 10s (100s?) of test flights. I've not heard of anything like that (some kind of fairing ejection simulator) being used to practice fairing recovery.

They did test drops of faring from helicopters: https://www.teslarati.com/spacex-mr-steven-falcon-fairing-catch-practice/
True, they spent considerable time doing tests on the west coast during the surge of launches out there. 

I love how SpaceX has used existing hardware and opportunities paid for by customers. 

F9 Booster and fairing reuse are excellent examples.
I stand corrected. It still is pretty tough.
Title: Re: Fairing reuse
Post by: Rondaz on 03/22/2020 04:27 pm
Fairing Recovery Attempts

BY SCR00CHY · 2020-03-21

https://www.elonx.net/fairing-recovery-attempts/
Title: Re: Fairing reuse
Post by: spacexfanatic on 04/12/2020 12:53 pm
I dont know if already debated here, but what about catching the firing in the air by a chopper like RocketLab. I think lot hazardous than the boatweb idea. may be more expences to equi the boat with Helipad and buy choppers but it may profitable on the long term.
Title: Re: Fairing reuse
Post by: woods170 on 04/12/2020 04:29 pm
I dont know if already debated here, but what about catching the firing in the air by a chopper like RocketLab. I think lot hazardous than the boatweb idea. may be more expences to equi the boat with Helipad and buy choppers but it may profitable on the long term.

Mid-air retrieval of the fairings was the original idea. But, SpaceX switched to boats with nets when they found out that the needed helicopters required a sea-borne take-off and landing platform. This was due to downrange distance from land, in combination with loiter time, exceeded the capabilities of most types of helicopters. Thus, the helicopters would have to be SHIPped out to sea, close to the recovery zone, perform the recovery mission and then land back on the ship, to be SHIPped back to land. Too much of a hassle and too expensive. When a ship is required to be near the recovery zone anyway, just as well have that ship catch the fairing. That eliminates the cost of the helicopter(s).

Another problem was that only a handfull of helicopter types are certified to operate hundreds of miles offshore which limited the choice of helicopter types.
Title: Re: Fairing reuse
Post by: freddo411 on 04/12/2020 05:05 pm
I dont know if already debated here, but what about catching the firing in the air by a chopper like RocketLab. I think lot hazardous than the boatweb idea. may be more expences to equi the boat with Helipad and buy choppers but it may profitable on the long term.

Mid-air retrieval of the fairings was the original idea. But, SpaceX switched to boats with nets when they found out that the needed helicopters required a sea-borne take-off and landing platform. This was due to downrange distance from land, in combination with loiter time, exceeded the capabilities of most types of helicopters. Thus, the helicopters would have to be SHIPped out to sea, close to the recovery zone, perform the recovery mission and then land back on the ship, to be SHIPped back to land. Too much of a hassle and too expensive. When a ship is required to be near the recovery zone anyway, just as well have that ship catch the fairing. That eliminates the cost of the helicopter(s).

Another problem was that only a handfull of helicopter types are certified to operate hundreds of miles offshore which limited the choice of helicopter types.

Based upon the present success rate (fairly low) seems like this would be a good job for a very large drone launched from the present recovery ships.    Seems like this could add the needed control authority during the last 500 meters of the landing
Title: Re: Fairing reuse
Post by: anof on 04/12/2020 05:11 pm
I dont know if already debated here, but what about catching the firing in the air by a chopper like RocketLab. I think lot hazardous than the boatweb idea. may be more expences to equi the boat with Helipad and buy choppers but it may profitable on the long term.

Another problem is controlling the fairing once it is caught. It has a large surface area with a relatively low mass. It will act like a giant parafoil and might be impossible to control in windy conditions.
Title: Re: Fairing reuse
Post by: john smith 19 on 04/12/2020 06:11 pm
Mid-air retrieval of the fairings was the original idea. But, SpaceX switched to boats with nets when they found out that the needed helicopters required a sea-borne take-off and landing platform. This was due to downrange distance from land, in combination with loiter time, exceeded the capabilities of most types of helicopters. Thus, the helicopters would have to be SHIPped out to sea, close to the recovery zone, perform the recovery mission and then land back on the ship, to be SHIPped back to land. Too much of a hassle and too expensive. When a ship is required to be near the recovery zone anyway, just as well have that ship catch the fairing. That eliminates the cost of the helicopter(s).

Another problem was that only a handfull of helicopter types are certified to operate hundreds of miles offshore which limited the choice of helicopter types.
The problem parameters are awkward.

Far offshore, very large (but "floppy") structure but OTOH not very heavy.

There's a ULA technical paper on the Selenian Boondocks site from the late oughties and they reckoned they need a CH53 Sea Stallion to do Atlas engine recovery (capture mass of about 25000lb). Of course the RD180 is much heavier.

So either you go with one of those "authorised" helicopters (I'm guessing they are all pretty big) or you design a custom flying drone to handle this.
Title: Re: Fairing reuse
Post by: john smith 19 on 04/12/2020 06:35 pm
Based upon the present success rate (fairly low) seems like this would be a good job for a very large drone launched from the present recovery ships.    Seems like this could add the needed control authority during the last 500 meters of the landing
That drone would either have to land back on the ASDS or on another ship.

The joker in the pack is where do you  land it?

The problem is that booster could land anywhere on the pad.  So, it's quite a big drone that has to maneuver a quite large structure (or rather two quite large structures) each on its own fairing retrieval ship

Now, where do you land those two drones?

As usual it's the combination of constraints that make this one of those "simple" ideas that IRL is actually a massive PITA to implement.  :( Spacex aren't in the design-a-large-airborn-drone business and don't want to be. OTOH if someone came to them with a fully developed drone design (at a reasonable price) they might reconsider.

SX is in the very early stages of using this technology. I'm remeinded of when they started booster recovery and were using hypergolic thrusters until they had enough data to shift to GN2 cold thrusters.

I expect as they rack up recoveries they will refine the package on each fairing along with the algorithms that both the fairings and the ships use to guide each part.

To me the really interesting part of this effort is that SX are continuing to pursue this. This suggests that the development budget is low enough, and the benefits high enough, for them to continue working on this.
Title: Re: Fairing reuse
Post by: su27k on 04/13/2020 02:34 am
Based upon the present success rate (fairly low) seems like this would be a good job for a very large drone launched from the present recovery ships.    Seems like this could add the needed control authority during the last 500 meters of the landing
That drone would either have to land back on the ASDS or on another ship.

The joker in the pack is where do you  land it?

The problem is that booster could land anywhere on the pad.  So, it's quite a big drone that has to maneuver a quite large structure (or rather two quite large structures) each on its own fairing retrieval ship

Now, where do you land those two drones?

Note we're talking about fairing recovery, not booster recovery. The drone can land in the net together with the fairing.

Quote
As usual it's the combination of constraints that make this one of those "simple" ideas that IRL is actually a massive PITA to implement.  :( Spacex aren't in the design-a-large-airborn-drone business and don't want to be. OTOH if someone came to them with a fully developed drone design (at a reasonable price) they might reconsider.

They did build a robot for securing booster on ASDS though, so they're not afraid of doing some robotic design if that's what is needed.
Title: Re: Fairing reuse
Post by: john smith 19 on 04/13/2020 06:06 am
Note we're talking about fairing recovery, not booster recovery. The drone can land in the net together with the fairing.
I'd look again at how big that net is and how big that payload fairing. I'd also consider how those two drones are going to fit into that net with it and which could damage which before they are secured.

Quote from: su27k
They did build a robot for securing booster on ASDS though, so they're not afraid of doing some robotic design if that's what is needed.
I'm not suggesting they are afraid of anything, merely that they are pragmatic.

IMHO People who suggest this idea seriously underestimate the complexities involved. It's big, it has to exert and control substantial forces and manage them with precision and there really needs to be two of them to handle both fairings at once. The FAA will want to be involved for both the construction and the operation.

However I also think that if someone came to them with a complete solution package, that had already done the complete drone development, that would be a different story. It would have to be complete and SX would have to control their copies of it. SX have a lot of past experience when some supplier is in their critical path and they don't like the loss of that much control.

So I think SX will continue to recover their fairings their way for now.  Some they will miss and I wonder if the fairings are made closely enough that they can be swapped around or if they can only be used as a matched pair? With only a few recoveries so far I think it's far too early to judge how reliable this process is. When they've done as many fairing recoveries as booster recoveries we should start to see some idea of how reliable the process can be.

It's going to be an exciting year.
Title: Re: Fairing reuse
Post by: spacexfanatic on 04/13/2020 08:29 am
The russian MI-26 helicopter can handle 20 tonnes of paylod and a ferry range of 1900 Km (800 Km range), the fairing is 1.9 tons so each part is approximatly 950 kgs each, which I think is manageable to catch by one chopper.

OCISLY can be used for refueling  the chopper (if needed), and the boatnet to catch the half of the fairing, and if things are well managed the can use only one ship for both halves.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 04/13/2020 10:46 am
To me the really interesting part of this effort is that SX are continuing to pursue this. This suggests that the development budget is low enough, and the benefits high enough, for them to continue working on this.

Also I suspect they think they’re close to more reliably catching the fairings in the nets and so it’s worth continuing. Really helps too that some of the water landings are soft enough that those fairings can still be reused and obviously they need boats out there anyway to retrieve them from the water.

SpaceX are really persistent when they think the goal is worth it. They spent two years, and numerous different solution attempts, on improving video stability just so the live picture wouldn’t cut out when a booster comes in to land on an ASDS.
Title: Re: Fairing reuse
Post by: john smith 19 on 04/13/2020 07:50 pm
The russian MI-26 helicopter can handle 20 tonnes of paylod and a ferry range of 1900 Km (800 Km range), the fairing is 1.9 tons so each part is approximatly 950 kgs each, which I think is manageable to catch by one chopper.

OCISLY can be used for refueling  the chopper (if needed), and the boatnet to catch the half of the fairing, and if things are well managed the can use only one ship for both halves.
You might like to check on how long a window you'd have between it dropping below the speed of sound and hitting the water.

Now you're asking to catch 2 of these pieces in that window.

The issue is not wheather or not helicopters exist that could do this. ULA identified a US helicopter that could handle the whole engine package for an Atlas V (or it's successor) in 2008. 

Actual issues are things like a)Is it licensed to operate over water at those sorts of ranges? Are any available in the US? What condition are they in?

If the answer is "Well they could be if SX was interested" then you have explain why would they bother, when they have a system that's starting to produce results and re-fly fairings already that's under their complete control.
Title: Re: Fairing reuse
Post by: wannamoonbase on 06/05/2020 05:15 pm
Does it make sense that the fairing halves that make it back to port but are broken, are likely damaged on landing or in recovery?

Maybe a failed net landing attempt or rough seas.

Seems if there was any problem in flight that they wouldn't get to the surface in the desired location.
Title: Re: Fairing reuse
Post by: Comga on 06/09/2020 11:49 pm
Cross-posting from the Starlink V1.0 L8 thread because of the great image of the recovery hardware inside the fairing.
Looks like this will be heaviest F9 payload to date:
https://twitter.com/thesheetztweetz/status/1270469107465490432 (https://twitter.com/thesheetztweetz/status/1270469107465490432)
Quote
I asked SpaceX if launching Planet's 3 SkySat satellites meant the company would have to reduce the number Starlink satellites from 60 on each launch but it looks like there's room at the top of the stack (view from inside the Falcon 9 rocket nosecone):
https://www.cnbc.com/2020/06/09/planets-skysats-will-take-images-up-to-12-times-a-day-launched-with-help-of-spacex.html (https://www.cnbc.com/2020/06/09/planets-skysats-will-take-images-up-to-12-times-a-day-launched-with-help-of-spacex.html)

Edit:  Video(s) here (https://twitter.com/SpaceX/status/1270466922459459590)
Title: Re: Fairing reuse
Post by: ZChris13 on 06/10/2020 07:19 am
Cross-posting from the Starlink V1.0 L8 thread because of the great image of the recovery hardware inside the fairing.
Looks like this will be heaviest F9 payload to date:
https://twitter.com/thesheetztweetz/status/1270469107465490432 (https://twitter.com/thesheetztweetz/status/1270469107465490432)
Quote
I asked SpaceX if launching Planet's 3 SkySat satellites meant the company would have to reduce the number Starlink satellites from 60 on each launch but it looks like there's room at the top of the stack (view from inside the Falcon 9 rocket nosecone):
https://www.cnbc.com/2020/06/09/planets-skysats-will-take-images-up-to-12-times-a-day-launched-with-help-of-spacex.html (https://www.cnbc.com/2020/06/09/planets-skysats-will-take-images-up-to-12-times-a-day-launched-with-help-of-spacex.html)

Edit:  Video(s) here (https://twitter.com/SpaceX/status/1270466922459459590)
This has also been posted to YouTube, in 1080p!
https://www.youtube.com/watch?v=aKWio4zHShM
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 06/16/2020 09:57 am
Speculation about possible 3rd flight (2nd reuse) of fairings:

Quote
Eric Ralph in NewsSpaceX 57 mins ago
SpaceX’s next rocket fairing reuse milestone within reach after latest recovery

SpaceX’s next major Falcon 9 fairing reuse milestone is now within reach after the company managed to successfully recover an entire reused nosecone with both halves intact.

https://www.teslarati.com/spacex-next-rocket-fairing-reuse-milestone/
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 06/16/2020 06:51 pm
Elon responds to article:

https://twitter.com/elonmusk/status/1272933424190218240

Quote
Fairing reuse is looking good
Title: Re: Fairing reuse
Post by: scr00chy on 06/16/2020 06:55 pm
The article isn't even correct. It's not the first time SpaceX recovered reused fairings intact, that happened on the Starlink v1-6 mission.
Title: Re: Fairing reuse
Post by: AndrewRG10 on 06/19/2020 06:38 am
The article isn't even correct. It's not the first time SpaceX recovered reused fairings intact, that happened on the Starlink v1-6 mission.

That's why I'm glad we have you who keeps track of this stuff properly. ArabSat 6a was the first time both halves were recovered, they got reused. Amos-17 fairings the same but were the first to be recovered a second time.
But remember, it's Teslarati, don't trust it to be reliable.
Title: Re: Fairing reuse
Post by: mulp on 06/24/2020 03:01 am
SpaceX has provided the public with lots of information on F9 first stage recovery, but very little on faring recovery.

Speculation on why?

Landing rockets like in 50s/60s scifi movies is so cool, even when crashing, but catchers missing fairings isn't?

GoPro cameras of fairings coming down cost too much?

F9 was designed from day to be recovered, somehow, and that gives SpaceX a decade advantage over everyone but Bezos/Blue Origin...

Fairings are a commodity produced by others designed for single use, so SpaceX might learn how to design for reuse and make them in house, so the less others know the better?

Why hasn't a faring maker stepped up and offered to develop reuse for SpaceX and any others? SpaceX would be the biggest winning customer, but by developing reuse, a faring maker would gain the value of reuse.

Starship is years away from taking over all launch, if ever, so fairings will only see increasing use for a long time. And global capacity, rocket engineers, capital, eg factories, pads, are not a constraint because we are still below the launch rate of the 60s, 70s, 80s.

Is the cost of making fairings more like a million for a pair instead of six million and the status quo of five million gross profit squandered on preserving the status quo with patents, overhead, etc is too lucrative to allow engineers to innovate?
Title: Re: Fairing reuse
Post by: matthewkantar on 06/24/2020 03:30 am
I dunno, if I sold an expensive product that customers were using once and throwing away, why would I want to make it reusable? Every single reuse is lost sale. If the buyer reaps all of the benefits, the seller is unmotivated.
Title: Re: Fairing reuse
Post by: robert_d on 06/24/2020 02:09 pm
It appears, based on Elon's tweet, that SpaceX is very close to more consistent net catches. But it may still be a somewhat low probability proposition. I would suggest that because the variability is in the trajectory of the fairing, just a small improvement to that might yield significant benefit.

My first thought was to provide a small set of drone like propeller/motors that would be used to dampen lateral motion. But that would add weight and decrease volume in the fairing. So what about launching a drone that would position itself just ahead of the fairing? It could measure very local wind conditions allowing a quicker response than directly using fairing movements. If that was insufficient, how about using two large drones from the ships tethered together with a cable and central snag? They would launch just in time to intercept the fairing say 180 - 300 meters up, approaching from behind and hopefully provide just enough additional stability to up the odds of recovery.     
Title: Re: Fairing reuse
Post by: jstrotha0975 on 06/24/2020 02:17 pm
SpaceX has provided the public with lots of information on F9 first stage recovery, but very little on faring recovery.

Speculation on why?

Landing rockets like in 50s/60s scifi movies is so cool, even when crashing, but catchers missing fairings isn't?

GoPro cameras of fairings coming down cost too much?

F9 was designed from day to be recovered, somehow, and that gives SpaceX a decade advantage over everyone but Bezos/Blue Origin...

Fairings are a commodity produced by others designed for single use, so SpaceX might learn how to design for reuse and make them in house, so the less others know the better?

Why hasn't a faring maker stepped up and offered to develop reuse for SpaceX and any others? SpaceX would be the biggest winning customer, but by developing reuse, a faring maker would gain the value of reuse.

Starship is years away from taking over all launch, if ever, so fairings will only see increasing use for a long time. And global capacity, rocket engineers, capital, eg factories, pads, are not a constraint because we are still below the launch rate of the 60s, 70s, 80s.

Is the cost of making fairings more like a million for a pair instead of six million and the status quo of five million gross profit squandered on preserving the status quo with patents, overhead, etc is too lucrative to allow engineers to innovate?

I remember reading something a year ago that RUAG wanted to make a deal with SpaceX, they would provide extra large fairings for FH in exchange for Reuse tecnology.
Title: Re: Fairing reuse
Post by: rsdavis9 on 06/24/2020 02:47 pm
It appears, based on Elon's tweet, that SpaceX is very close to more consistent net catches. But it may still be a somewhat low probability proposition. I would suggest that because the variability is in the trajectory of the fairing, just a small improvement to that might yield significant benefit.

My first thought was to provide a small set of drone like propeller/motors that would be used to dampen lateral motion. But that would add weight and decrease volume in the fairing. So what about launching a drone that would position itself just ahead of the fairing? It could measure very local wind conditions allowing a quicker response than directly using fairing movements. If that was insufficient, how about using two large drones from the ships tethered together with a cable and central snag? They would launch just in time to intercept the fairing say 180 - 300 meters up, approaching from behind and hopefully provide just enough additional stability to up the odds of recovery.   

So tracking while the fairings are at a high altitude isn't sufficient? With the high speeds the boats are capable of you would think that would give enough time for the boats to position?
Title: Re: Fairing reuse
Post by: freddo411 on 06/24/2020 04:00 pm
A couple of reasons we don't see a fairing reuse attempts from others:

* Cadence.   The low cadence of other launch providers means that the fixed costs of the recovery fleet eat significantly into any profit margin.   Also, many flights are needed during development and testing.

* Payload penalty.   Recovery hardware adds mass that subtracts some from maximum payload.   

* Customer restrictions.   NASA/DOD would be very unlikely to encourage this on most launches.
Title: Re: Fairing reuse
Post by: anof on 06/24/2020 05:41 pm
I seem to remember that SpaceX only had one autoclave for fairings and did not want to invest in a second one. I also remember reading that SpaceX fairings are actually heaver and stiffer than most industry fairings. That helps with recovery and also SpaceX makes their fairings in-house.
Title: Re: Fairing reuse
Post by: wannamoonbase on 06/24/2020 08:10 pm
I seem to remember that SpaceX only had one autoclave for fairings and did not want to invest in a second one. I also remember reading that SpaceX fairings are actually heaver and stiffer than most industry fairings. That helps with recovery and also SpaceX makes their fairings in-house.

One aspect of SpaceX's approach to fairings that is not mentioned very often, is that simplicity of using a single size.  They could save cost and improve performance with smaller fairing sizes.  but they decided to go with a 1 size option.

I think it's a great idea to keep over all costs down. 
Title: Re: Fairing reuse
Post by: robert_d on 07/06/2020 01:03 pm
   I would suggest that because the variability is in the trajectory of the fairing, just a small improvement to that might help.

   What about launching a drone that would position itself just ahead of the fairing? It could measure very local wind conditions allowing a quick response. If that was insufficient, how about using two large drones from the ships tethered together with a cable and central snag? Launched just in time to intercept the fairing say 300 meters up, they would provide just enough additional stability to up the odds of recovery.   

So tracking while the fairings are at a high altitude isn't sufficient? With the high speeds the boats are capable of you would think that would give enough time for the boats to position?

Well, apparently not as the low level winds and sometimes difficult sea states make course predictions for both fairing and ship a bit difficult. So much so that they did not even attempt a net recovery this last time.
Title: Re: Fairing reuse
Post by: wannamoonbase on 07/06/2020 05:37 pm
   I would suggest that because the variability is in the trajectory of the fairing, just a small improvement to that might help.

   What about launching a drone that would position itself just ahead of the fairing? It could measure very local wind conditions allowing a quick response. If that was insufficient, how about using two large drones from the ships tethered together with a cable and central snag? Launched just in time to intercept the fairing say 300 meters up, they would provide just enough additional stability to up the odds of recovery.   

So tracking while the fairings are at a high altitude isn't sufficient? With the high speeds the boats are capable of you would think that would give enough time for the boats to position?

Well, apparently not as the low level winds and sometimes difficult sea states make course predictions for both fairing and ship a bit difficult. So much so that they did not even attempt a net recovery this last time.


I'm sure they are using a closed loop and taking feedback from the chute operation and how it is affecting it's course against what is expected.

I'm impressed they are getting as close as they are with something so big, going through the entire atmosphere.  It's crazy, it's not a plane, doesn't have wings, it's amazing they have accomplished this much.  I love it.

But I'm ok with the fairing free future of SS as well.
Title: Re: Fairing reuse
Post by: Tulse on 07/06/2020 06:21 pm
SpaceX seems to be doing so well with recovery from the ocean -- is this their new strategy? And have they done anything recently to the fairings specifically to salt-water-proof them and make this approach more viable?
Title: Re: Fairing reuse
Post by: butters on 07/06/2020 06:33 pm
   I would suggest that because the variability is in the trajectory of the fairing, just a small improvement to that might help.

   What about launching a drone that would position itself just ahead of the fairing? It could measure very local wind conditions allowing a quick response. If that was insufficient, how about using two large drones from the ships tethered together with a cable and central snag? Launched just in time to intercept the fairing say 300 meters up, they would provide just enough additional stability to up the odds of recovery.   

So tracking while the fairings are at a high altitude isn't sufficient? With the high speeds the boats are capable of you would think that would give enough time for the boats to position?

Well, apparently not as the low level winds and sometimes difficult sea states make course predictions for both fairing and ship a bit difficult. So much so that they did not even attempt a net recovery this last time.

They haven't attempted a net catch for several months because they are rewriting the software. There is a go/no-go poll for the catch that includes wind and sea conditions, but it's always no-go for now until the software update is deployed.
Title: Re: Fairing reuse
Post by: rpaulsen on 07/08/2020 11:58 am
Kind of a silly question but...  After seeing the fairing re-entry videos I was wondering if you had a space suit like Felix Baumgartner's, could you surf or ride down a fairing?
Title: Re: Fairing reuse
Post by: JamesH65 on 07/08/2020 12:14 pm
Kind of a silly question but...  After seeing the fairing re-entry videos I was wondering if you had a space suit like Felix Baumgartner's, could you surf or ride down a fairing?

I'm expecting this to be a sport within 50 years. Or something out of Starship troopers (the book, not the film)
Title: Re: Fairing reuse
Post by: Zed_Noir on 07/08/2020 12:18 pm
Kind of a silly question but...  After seeing the fairing re-entry videos I was wondering if you had a space suit like Felix Baumgartner's, could you surf or ride down a fairing?

Have you been watching the Dark Star movie from 1974?
https://en.wikipedia.org/wiki/Dark_Star_(film) (https://en.wikipedia.org/wiki/Dark_Star_(film))
Title: Re: Fairing reuse
Post by: ChrisWilson68 on 07/08/2020 01:03 pm
Kind of a silly question but...  After seeing the fairing re-entry videos I was wondering if you had a space suit like Felix Baumgartner's, could you surf or ride down a fairing?

In the 1960s there was a project (all the best wacky aerospace projects are from the 1960s)  MOOSE.  It was a way for an astronaut to get from orbit to Earth in an emergency.

Quote
The system was quite compact, weighing 200 lb (91 kg) and fitting inside a suitcase-sized container. It consisted of a small twin-nozzle rocket motor sufficient to deorbit the astronaut, a PET film bag 6 ft (1.8 m) long with a flexible 0.25 in (6.4 mm) ablative heat shield on the back, two pressurized canisters to fill it with polyurethane foam, a parachute, radio equipment and a survival kit.

The astronaut would leave the vehicle in a space suit, climb inside the plastic bag, and then fill it with foam. The bag had the shape of a blunt cone, with the astronaut embedded in its base facing outward. The rocket pack would protrude from the bag and be used to slow the astronaut's orbital speed enough so that they would reenter Earth's atmosphere, and the foam-filled bag would act as insulation during the subsequent aerobraking. Finally, once the astronaut had descended to 30,000 ft (9.1 km) where the air was sufficiently dense, the parachute would automatically deploy and slow the astronaut's fall to 17 mph (7.6 m/s). The foam heat shield would serve a final role as cushioning when the astronaut touched down and as a flotation device should they land on water.

https://en.wikipedia.org/wiki/MOOSE

You know that someday, somebody is going to do this.
Title: Re: Fairing reuse
Post by: rpaulsen on 07/08/2020 01:18 pm
Ha.. Had not seen Dark Star but it sounds like a classic according to Wikipedia.  Yes I recall the diagrams of the MOOSE project too!
Title: Re: Fairing reuse
Post by: ClayJar on 07/20/2020 09:43 pm
So, during the pre-launch portion of SpaceX's ANASIS-II webcast (https://youtube.com/watch?v=TshvZlQ7le8), just inside T-9 minutes, they said:

Quote from: SpaceX ANASIS-II Mission webcast
Two minutes before the fairings are set to land the team will decide if conditions are good to make a safe catch attempt.

Is this new info to us?
Title: Re: Fairing reuse
Post by: scr00chy on 07/20/2020 09:55 pm
So, during the pre-launch portion of SpaceX's ANASIS-II webcast (https://youtube.com/watch?v=TshvZlQ7le8), just inside T-9 minutes, they said:

Quote from: SpaceX ANASIS-II Mission webcast
Two minutes before the fairings are set to land the team will decide if conditions are good to make a safe catch attempt.

Is this new info to us?
No. They've said on previous webcasts that they make this decision at T+40 minutes, which is the same thing.
Title: Re: Fairing reuse
Post by: ClayJar on 07/20/2020 09:59 pm
No. They've said on previous webcasts that they make this decision at T+40 minutes, which is the same thing.

Ah, now that you mention it, I do seem to recall that.  I suppose my brain just considers it more concrete when it's relative to landing, which I suppose isn't that far off, as it would seem likely the atmosphere varies a bit, launch to launch.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 07/20/2020 10:27 pm
 :D

Yes, a first!

https://twitter.com/elonmusk/status/1285338582849208320

Quote
Both fairing halves caught from space by @SpaceX ships!
Title: Re: Fairing reuse
Post by: darkenfast on 07/21/2020 03:01 am
Apologies if I missed it, but do we know just where SpaceX refurbishes the fairing halves? They don't ship them back to Hawthorne, do they? 
Title: Re: Fairing reuse
Post by: scr00chy on 07/21/2020 11:12 am
Apologies if I missed it, but do we know just where SpaceX refurbishes the fairing halves? They don't ship them back to Hawthorne, do they?
At least some of them seem to have been refurbished at the old Spacehab facility at Port Canaveral: https://twitter.com/ken_kremer/status/1134517449871822848
Title: Re: Fairing reuse
Post by: wannamoonbase on 07/21/2020 04:00 pm
Apologies if I missed it, but do we know just where SpaceX refurbishes the fairing halves? They don't ship them back to Hawthorne, do they?
At least some of them seem to have been refurbished at the old Spacehab facility at Port Canaveral: https://twitter.com/ken_kremer/status/1134517449871822848

I am having a hard time waiting for video of yesterday's catches.

It's still incredible to me that they are able to a Falcon 9 level launch and only expend the upper stage.  It's absolutely crazy, even if it does require a small navy.
Title: Re: Fairing reuse
Post by: scr00chy on 07/21/2020 06:33 pm
https://twitter.com/SpaceX/status/1285632635335782401

Edit: Side-by-side YouTube version:

https://www.youtube.com/watch?v=69sZkYp4xEY
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 08/18/2020 11:48 am
Brilliant! Spot the subtle fairing recovery ship logo to indicate it’s been recovered (caught?) previously

twitter.com/trevormahlmann/status/1295687732367368192

Quote
Hat trick🪂 @elonmusk
Thanks to @thomas199920 for pointing this out to me.

⚙️/⬇️/🖼: tmahlmann.com/photos/Rockets…

Edit to add:

https://twitter.com/trevormahlmann/status/1295689288361943042

Quote
Clearer shot of the GO Ms. Tree / GO Ms. Chief silhouette on the reused fairings for the eleventh #Starlink mission this morning 🚀 So cool!

⚙️/⬇️/🖼: tmahlmann.com/photos/Rockets…

Further edit: it does mean caught; there’s a wave symbol for recovered from the sea

https://twitter.com/trevormahlmann/status/1295692416998158340

Quote
Yeah! Same here!

Here are close ups of both the scooped and ship-caught icons:
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 08/18/2020 09:41 pm
Interesting detail on autopilot

twitter.com/elonmusk/status/1295837003444039682

Quote
Ms Tree catches fairing in her net

https://twitter.com/elonmusk/status/1295837513987305474

Quote
Fairing chute control & ship control are closing the loop locally. Both operating on (SpaceX) autopilot.
Title: Re: Fairing reuse
Post by: AndrewRG10 on 08/18/2020 11:58 pm
This pair of fairings had one net caught and one splashed down on their first flight. Will it be possible to figure out if the caught fairing was the one caught last time or the one that splashed down.
Wondering if we know whether it was the half with the logo last time and infer it's the one with the logo this time or the opposite.
Title: Re: Fairing reuse
Post by: wannamoonbase on 08/19/2020 12:37 am
I think this was the third time a used fairing was flown, maybe it was the fourth.  Can anyone confirm?

Also: I’d love to see the videos they have of fairing recovery.  Especially as they were learning how to fly and control the fairing halves.  That’s be some killer stuff.
Title: Re: Fairing reuse
Post by: scr00chy on 08/19/2020 12:52 am
This was the fifth launch with reused fairings.
Title: Re: Fairing reuse
Post by: AndrewRG10 on 08/19/2020 01:04 am
I have just come across images which show that the fairing caught in the net last time features a fairing catcher insigma on it. When the fairing comes back to port on MsTree, observers should be able to see which one was caught, and whether a fairing was caught twice for the first time.

(https://i.imgur.com/ux8cVeJ.jpg)
Title: Re: Fairing reuse
Post by: TorenAltair on 08/19/2020 10:23 am
Just seen that FutureSpaceTourist slacked today  ;D 8)

https://mobile.twitter.com/elonmusk/status/1295847382073171970
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 08/19/2020 08:47 pm
In an attempt to make amends for my shocking lapse yesterday, here’s the YouTube version posted by SpaceX

https://youtu.be/oTH3mq7SsK4

Quote
SpaceX’s fairing recovery vessel Ms. Tree catches a Falcon 9 fairing half after launch of SpaceX’s eleventh Starlink mission on August 18, 2020. The fairing used on this mission previously flew in support of SpaceX’s fourth Starlink mission.
Title: Re: Fairing reuse
Post by: MarkRob on 09/05/2020 01:50 pm
This capture net design just doesn't seem to be working very reliably,
 I've been wondering if they could drop a line of high tensile strength cord (dyneema or similar) from the fairing at about 1km altitude, then have the capture boat intercept the line and reel in the parafoil supported fairing using a winch.

This might be more reliable, and no net required either.
Title: Re: Fairing reuse
Post by: Robotbeat on 09/05/2020 04:29 pm
This capture net design just doesn't seem to be working very reliably,
 I've been wondering if they could drop a line of high tensile strength cord (dyneema or similar) from the fairing at about 1km altitude, then have the capture boat intercept the line and reel in the parafoil supported fairing using a winch.

This might be more reliable, and no net required either.
The net itself is pretty cheap. Reliability is the issue. I think there's probably lots of room for innovation, there (I mean, a big net is kind of a kludgy solution), but also SpaceX is likely to keep improving just through practice and tweaks, like they did with barge landing.
Title: Re: Fairing reuse
Post by: JamesH65 on 09/07/2020 11:25 am
This capture net design just doesn't seem to be working very reliably,
 I've been wondering if they could drop a line of high tensile strength cord (dyneema or similar) from the fairing at about 1km altitude, then have the capture boat intercept the line and reel in the parafoil supported fairing using a winch.

This might be more reliable, and no net required either.

Same issues as with the net - getting the boat under and catching the thing. Finding that cord dangling from a descending thing the size of a bus where its flight path is constantly affected by wind gust and then reeling in would be no easier that catching the thing itself.
Title: Re: Fairing reuse
Post by: MarkRob on 09/07/2020 12:51 pm
Intercepting the cord is a simple 2d challenge with around 4 minutes to intercept, intercepting the fairing is a one shot challenge in 2d where you must intercept at a specific time.

However, there is an issue with intercepting the cord: tangling with the boat superstructure, I'm not sure how practical it would be. Maybe launch a large UAV from the boat with a harpoon gun to capture the fairing, then winch in with a conventional winch.

On the other hand, there is another explanation for what's happening: they have oversized the parafoil so that ocean landing is feasible without damaging the fairing under most sea states. This will make the fairing fly more slowly and be more vulnerable to gusts. If the guidance control looks to be good enough, they could fit smaller parafoils to fairings when they plan to have recovery boats in position, then the high velocity might make them less vulnerable to wind gusts, but they would be damaged if they hit the sea.
Title: Re: Fairing reuse
Post by: volker2020 on 09/07/2020 01:00 pm
I always thought, the long term solution would be a drone, capturing / connecting to the parachute in flight and directing it to the ship.

Than, with Spaceship on the horizon, the question is, do they need a long term solution for Fairing Reuse.
Title: Re: Fairing reuse
Post by: JamesH65 on 09/07/2020 02:27 pm
These fairings are VERY LARGE, and VERY LIGHT and act like huge sails in the air. To counteract that the drone would need to be huge. Much bigger than any hover capable drone currently made.

Whether catching by net, catching a dangling line or whatever, this is not an easy task. And yet they are still fairly successful, so I'm thinking the net approach is actually a pretty good one - the fact they haven't given up with it makes me think that the alternatives are worse.
Title: Re: Fairing reuse
Post by: Jeff Lerner on 09/07/2020 02:34 pm
Any thoughts on why both fairings on the latest flight were so beaten up ..??..not sure what the sea  states were but I’m assuming both fairing haves landed softly in the water...

Perhaps something happened during the entry phase of fairings return on this flight which seriously weakened their structure.??
Title: Re: Fairing reuse
Post by: freddo411 on 09/07/2020 04:11 pm
These fairings are VERY LARGE, and VERY LIGHT and act like huge sails in the air. To counteract that the drone would need to be huge. Much bigger than any hover capable drone currently made.

Whether catching by net, catching a dangling line or whatever, this is not an easy task. And yet they are still fairly successful, so I'm thinking the net approach is actually a pretty good one - the fact they haven't given up with it makes me think that the alternatives are worse.

Google for demos of large collections of drones acting in a coordinated manner.    It solves your "drones aren't large enough" objection.
Title: Re: Fairing reuse
Post by: Mandella on 09/07/2020 04:30 pm
Any thoughts on why both fairings on the latest flight were so beaten up ..??..not sure what the sea  states were but I’m assuming both fairing haves landed softly in the water...

Perhaps something happened during the entry phase of fairings return on this flight which seriously weakened their structure.??

Absolutely guessing, but I suspect they were catches then fumbles -- meaning they "caught" them in the net and they blew/rolled off after their parachute had been cut away. We've seen that nearly happen on a couple of the actual catches, and I imagine falling sideways into the wake from the speeding ship would be enough to break the fairings up.

Again, speculating here.
Title: Re: Fairing reuse
Post by: HVM on 09/07/2020 04:31 pm
Any thoughts on why both fairings on the latest flight were so beaten up ..??..not sure what the sea  states were but I’m assuming both fairing haves landed softly in the water...

Perhaps something happened during the entry phase of fairings return on this flight which seriously weakened their structure.??
Either fairings were at swell so long, that it chop them up, or they hit booms or other parts of ships.

Edit: Or what Mandella is saying --^
Title: Re: Fairing reuse
Post by: JamesH65 on 09/07/2020 07:26 pm
These fairings are VERY LARGE, and VERY LIGHT and act like huge sails in the air. To counteract that the drone would need to be huge. Much bigger than any hover capable drone currently made.

Whether catching by net, catching a dangling line or whatever, this is not an easy task. And yet they are still fairly successful, so I'm thinking the net approach is actually a pretty good one - the fact they haven't given up with it makes me think that the alternatives are worse.

Google for demos of large collections of drones acting in a coordinated manner.    It solves your "drones aren't large enough" objection.

No, it really doesn't. Each drone would need to anchor itself somewhere on the fairing, so close the props won't be efficient, and you need a LOT of them to be able to steer the fairing. Or were you thinking enough drones could 'blow' the fairing in the right direction?

Title: Re: Fairing reuse
Post by: DistantTemple on 09/07/2020 07:37 pm
Any thoughts on why both fairings on the latest flight were so beaten up ..??..not sure what the sea  states were but I’m assuming both fairing haves landed softly in the water...

Perhaps something happened during the entry phase of fairings return on this flight which seriously weakened their structure.??
Either fairings were at swell so long, that it chop them up, or they hit booms or other parts of ships.

Edit: Or what Mandella is saying --^
Maybe if they are in a heavy swell for too long, the parachutes act like sea anchors, and the waves cause the fairings to snub against the parachute lines. These lines are supposed to support the fairing from above as it sinks through the atmosphere, but if the fairing goes sideways on to the waves and the restraint of these ropes, then it will be violently stressed sideways, which it is not designed for. Also if on of the lines got wrapped around it, from maybe it rolling, then a fairing weighted with water, snubbing against an encircling rope, would likely be crushed and cut by that rope.
Maybe they auto detach the parachute lines, but we haven't seen that in the shared clips.

Edit: Then once its obviously damaged there is no point in taking care getting it aboard, and avoiding impacts on the way, especially if it risky for the crew as it swings around.
Title: Re: Fairing reuse
Post by: volker2020 on 09/07/2020 07:45 pm
These fairings are VERY LARGE, and VERY LIGHT and act like huge sails in the air. To counteract that the drone would need to be huge. Much bigger than any hover capable drone currently made.

Whether catching by net, catching a dangling line or whatever, this is not an easy task. And yet they are still fairly successful, so I'm thinking the net approach is actually a pretty good one - the fact they haven't given up with it makes me think that the alternatives are worse.

I guess you misunderstood me in some ways. A drone wouldn't have to carry the fairings kilometers away. All they have to archive is to give them a little bit more control authority. They could probe the weather, while flying up, thereby increasing the accuracy of the flight model (the parachutes are already controlled, and may add some accuracy, while controlling the fall. Would still be some work, but clearly in the range of doable.
Title: Re: Fairing reuse
Post by: freddo411 on 09/07/2020 09:39 pm
These fairings are VERY LARGE, and VERY LIGHT and act like huge sails in the air. To counteract that the drone would need to be huge. Much bigger than any hover capable drone currently made.

Whether catching by net, catching a dangling line or whatever, this is not an easy task. And yet they are still fairly successful, so I'm thinking the net approach is actually a pretty good one - the fact they haven't given up with it makes me think that the alternatives are worse.

Google for demos of large collections of drones acting in a coordinated manner.    It solves your "drones aren't large enough" objection.

No, it really doesn't. Each drone would need to anchor itself somewhere on the fairing, so close the props won't be efficient, and you need a LOT of them to be able to steer the fairing. Or were you thinking enough drones could 'blow' the fairing in the right direction?



Watch this demo:   https://www.youtube.com/watch?v=hyGJBV1xnJI

Obviously a much smaller scale than fairings, by 2 or 3 orders of magnitude.   Observe that the drones can be 10 times their size or more  away from the load.    Instead of three drones in this demo, one can scale up the number of drones to 30 or 300.

Once the drones snare some part of the fairing or parachute, you can imagine them exerting forces.   Note that the forces don't have to be great enough to hold the entire weight of the fairing;   all that is needed is to add some additional control authority.

One concept I read about here was to have the fairing have a several hundred meter trailing cord.   This could be grabbed by a drone, and brought to the ship, then the fairing reeled in.
Title: Re: Fairing reuse
Post by: meekGee on 09/08/2020 05:37 am
This capture net design just doesn't seem to be working very reliably,
 I've been wondering if they could drop a line of high tensile strength cord (dyneema or similar) from the fairing at about 1km altitude, then have the capture boat intercept the line and reel in the parafoil supported fairing using a winch.

This might be more reliable, and no net required either.

Same issues as with the net - getting the boat under and catching the thing. Finding that cord dangling from a descending thing the size of a bus where its flight path is constantly affected by wind gust and then reeling in would be no easier that catching the thing itself.
I've always thought of this drop cord method.

The intercept is not time dependent since the cord is long, and can be done with a much more nimble boat.

Once captured, the boat can keep pulling on the line indefinitely..  and eventually line up with the wind and capture it with a much smaller net.

I'm sure they've thought of that though.

--

I think maybe he problem they have remaining is missing by miles, not by yards. 

Uncertainty in winds, limited control authority of the fairing through EDL, finite speed of the boats...  That's harder to solve.
Title: Re: Fairing reuse
Post by: Hobbes-22 on 09/08/2020 07:31 am
A cord in the water is a hazard for the ship (can get caught in the propellers/waterjet intakes).
Title: Re: Fairing reuse
Post by: JamesH65 on 09/08/2020 10:04 am
These fairings are VERY LARGE, and VERY LIGHT and act like huge sails in the air. To counteract that the drone would need to be huge. Much bigger than any hover capable drone currently made.

Whether catching by net, catching a dangling line or whatever, this is not an easy task. And yet they are still fairly successful, so I'm thinking the net approach is actually a pretty good one - the fact they haven't given up with it makes me think that the alternatives are worse.

Google for demos of large collections of drones acting in a coordinated manner.    It solves your "drones aren't large enough" objection.

No, it really doesn't. Each drone would need to anchor itself somewhere on the fairing, so close the props won't be efficient, and you need a LOT of them to be able to steer the fairing. Or were you thinking enough drones could 'blow' the fairing in the right direction?



Watch this demo:   https://www.youtube.com/watch?v=hyGJBV1xnJI

Obviously a much smaller scale than fairings, by 2 or 3 orders of magnitude.   Observe that the drones can be 10 times their size or more  away from the load.    Instead of three drones in this demo, one can scale up the number of drones to 30 or 300.

Once the drones snare some part of the fairing or parachute, you can imagine them exerting forces.   Note that the forces don't have to be great enough to hold the entire weight of the fairing;   all that is needed is to add some additional control authority.

One concept I read about here was to have the fairing have a several hundred meter trailing cord.   This could be grabbed by a drone, and brought to the ship, then the fairing reeled in.

I'm perfectly aware of cooperative drone flying, that is not the point. You seem to be massively underestimating the amount of control authority needed to steer something this big whilst under a parachute.  It would be MUCH easier just to add flaps to the fairings themselves if all you wanted was the control authority that a drone or set of drones could give you. And how do they attach to the fairing? Just think about the issues here before proposing some hair brained drone scheme. Then think - SpaceX are not stupid, and they have not even tried this approach. Why? Because it sucks.
Title: Re: Fairing reuse
Post by: MarkRob on 09/08/2020 02:56 pm
wow people missing the point!
The drone would carry less than 10kg of dyneema (or similar) line from a boat mounted winch.
This would then be attached using a (small, compressed air powered) harpoon gun.
Then a conventional winch could be used to leisurely pull in the fairing with parafoil acting as a "crane"
Title: Re: Fairing reuse
Post by: JamesH65 on 09/09/2020 10:50 am
wow people missing the point!
The drone would carry less than 10kg of dyneema (or similar) line from a boat mounted winch.
This would then be attached using a (small, compressed air powered) harpoon gun.
Then a conventional winch could be used to leisurely pull in the fairing with parafoil acting as a "crane"

It's easy to miss the point if that point has never been written down.

So, this makes more sense. There are drones that could carry that sort of weight, but I'd be concerned about the harpoon system - you really don't want to damage the fairing in that way, if indeed you can mount a harpoon and fire from a drone accurately enough - has this ever been done? But you still need to get the boat to the capture line which strikes me as a similar problems to just getting the net underneath in the current system.
Title: Re: Fairing reuse
Post by: MarkRob on 09/09/2020 11:18 am
Actually I think there might be an even simpler way to do this:
1) Fairing nose drops a short length (maybe 30m) of line with a three pronged grapping hook on the end
2) Conventional kiteboarding kite (or equivalent) with upgraded lines launched from boat deck
3) Kite flown so the line is captured by the grapping hook
4) A winch attached to the kite line is used to pull in the fairing (boat is directed into the wind for this stage)
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 09/17/2020 01:16 am
https://twitter.com/spacexfleet/status/1306382465410494471

Quote
A fairing half is going for its third flight! From my records, the half has been recovered from the water twice and never caught in a net. (Missions V0. 9 and V1 L5)
SpaceXFleet.com/fairing-data

twitter.com/spacex/status/1306378025785647106

Quote
A fairing half supporting this mission previously supported Starlink missions in May 2019 and March 2020
Title: Re: Fairing reuse
Post by: octavo on 09/18/2020 05:11 am
Actually I think there might be an even simpler way to do this:
1) Fairing nose drops a short length (maybe 30m) of line with a three pronged grapping hook on the end
2) Conventional kiteboarding kite (or equivalent) with upgraded lines launched from boat deck
3) Kite flown so the line is captured by the grapping hook
4) A winch attached to the kite line is used to pull in the fairing (boat is directed into the wind for this stage)

Have you kiteboarded in a decent wind before? I suspect you would not suggest trying to fly a kite on a boat at sea, while trying to capture a multi-ton carbon fibre sail, if you had. They are extremely powerful and in gusty conditions can be frightening.

 If you are suggesting that the kite be flown by robotic winch, then your idea of 'simpler' may not accord with everyone else's.
Title: Re: Fairing reuse
Post by: AndrewRG10 on 10/06/2020 11:53 am
I believe this is the first time the amount of flights aimed for a fairing has been talked about. Elon Musk saying they're aiming for 10 flights of a fairing (and booster) by end of next year

https://twitter.com/elonmusk/status/1313446518695763968

Quote
Ahem, yes, it was the 3rd flight of this booster & 3rd flight for active half of fairing. Aiming for 10+ flights of booster & fairing by end of next year.
Title: Re: Fairing reuse
Post by: Rekt1971 on 10/17/2020 10:38 am
Quote
The booster supporting this launch has flown on five previous missions, and this mission will be the third flight for both fairing halves

https://twitter.com/SpaceX/status/1317410924529999872

Title: Re: Fairing reuse
Post by: Cheapchips on 10/18/2020 01:52 pm
The corner of the net on Miss Tree gave away on today's catch.  I think that's a first?

(whether the fairing is ok tbc)
Title: Re: Fairing reuse
Post by: Jeff Lerner on 10/18/2020 02:19 pm
The corner of the net on Miss Tree gave away on today's catch.  I think that's a first?

(whether the fairing is ok tbc)



Adding Steven’s screen shot...
Title: Re: Fairing reuse
Post by: scr00chy on 10/18/2020 07:57 pm
Since SpaceX hasn't specified it, I was trying to figure out which missions today's fairings flew on previously. At first I thought they were the ones from Amos-17 and Starlink v1-6 since they were the oldest recovered ones, but then I realized the fairing today had the Starlink X on it. That means it has to be the half from Starlink v1-2 and Starlink v1-8, while the other half is likely from Kacific-1 and Starlink v1-8.
Title: Re: Fairing reuse
Post by: Comga on 11/05/2020 06:47 pm
https://www.flickr.com/photos/nasakennedy/50569929502/ (https://www.flickr.com/photos/nasakennedy/50569929502/)

Quote
KSC-20201103-PH-RNB01_0009
Inside SpaceX's Payload Processing Facility at Vandenberg Air Force Base in California, the U.S.-European Sentinel-6 Michael Freilich ocean-monitoring satellite is being encapsulated in the SpaceX Falcon 9 payload fairing on Nov. 3, 2020. Sentinel-6 is scheduled to launch on Nov. 21, 2020, at 12:17 p.m. EST (9:17 a.m. PST), atop the SpaceX Falcon 9 rocket from Space Launch Complex 4E at Vandenberg Air Force Base. The Launch Services Program at Kennedy is responsible for launch management. Photo credit: NASA/Randy Beaudoin

The spacecraft is rather ordinary, the people of interest only to themselves and their families, but the details on the fairing hardware are truly interesting.
Title: Re: Fairing reuse
Post by: ZachS09 on 02/16/2021 09:40 pm
Has SpaceX given up on catching the fairings in Ms. Chief and Ms. Tree's nets?

Per https://www.elonx.net/fairing-recovery-attempts/, there haven't been that many catch attempts lately.
Title: Re: Fairing reuse
Post by: spacenut on 02/16/2021 09:42 pm
In the last launch, Elon tweeted the caught one of the fairing halves.  The primary one with the controls.  Don't know about the other one.  Sometimes they fish them out of the sea. 
Title: Re: Fairing reuse
Post by: scr00chy on 02/16/2021 10:03 pm
Has SpaceX given up on catching the fairings in Ms. Chief and Ms. Tree's nets?

Per https://www.elonx.net/fairing-recovery-attempts/, there hasn't been that many catch attempts lately.

I don't think they've given up on it. They've recently been testing the nets in port, for example. But lately there simply haven't been many opportunities for catch attempts. Seems to me SpaceX only attempts to catch fairings when:

1) Both Ms. Chief and Ms. Tree are present
2) The weather is very good (possibly because a failed catch attempt increases the chance the fairing will get damaged)
3) The ships aren't needed for two missions in quick succession (without going to port in between them)

And in the past few months, these "requirements" have rarely been met for various reasons. For example, after Starlink v1-14, both Ms. Tree and Ms. Chief were damaged and needed repairs and maintenance. Ms. Tree was out of service for two months, so Ms. Chief had to deployed either on her own or with a non-catcher ship.

After Ms. Tree was repaired, the weather has been mostly bad. And in those few cases where the weather might have been fine, the ships were deployed for two missions at once. And from what I understand, once either ship catches a fairing in the net, it cannot scoop up another half from the water. So if you need to recover four fairing halves from two missions with only two ships, they all need to be recovered from the water (unless the ships have time to unload in port in between the two launches).

In the last launch, Elon tweeted the caught one of the fairing halves.  The primary one with the controls.  Don't know about the other one.  Sometimes they fish them out of the sea. 

The fairing Elon was talking about was recovered from the water. SpaceX said in the webcast that they weren't attempting to catch them in the nets on that mission.
Title: Re: Fairing reuse
Post by: Asteroza on 03/11/2021 12:10 am
With the arms being taken of Ms. Tree and Ms. Chief, they've given up on net catches for now. They're also refitting other SpaceX fleet ships to do water pickups as well, to increase catch fleet size.
Title: Re: Fairing reuse
Post by: Jansen on 03/13/2021 02:07 pm
Crosspost:
Quote
SpaceX is targeting Sunday, March 14 for launch of 60 Starlink satellites from Launch Complex 39A (LC-39A) at Kennedy Space Center in Florida. The instantaneous window is at 6:01 a.m. EDT, or 10:01 UTC.

The Falcon 9 first stage rocket booster supporting this mission previously supported launch of Crew Dragon’s first demonstration mission, RADARSAT Constellation Mission, SXM-7, and five Starlink missions. Following stage separation, SpaceX will land Falcon 9’s first stage on the “Of Course I Still Love You” droneship, which will be located in the Atlantic Ocean. Falcon 9’s fairing previously flew on the Transporter-1 mission.

Taking that to mean both halves. Is this the first dual reuse of a pair together?

Turnaround is pretty short as well.
Title: Re: Fairing reuse
Post by: scr00chy on 03/13/2021 02:12 pm
Crosspost:
Quote
SpaceX is targeting Sunday, March 14 for launch of 60 Starlink satellites from Launch Complex 39A (LC-39A) at Kennedy Space Center in Florida. The instantaneous window is at 6:01 a.m. EDT, or 10:01 UTC.

The Falcon 9 first stage rocket booster supporting this mission previously supported launch of Crew Dragon’s first demonstration mission, RADARSAT Constellation Mission, SXM-7, and five Starlink missions. Following stage separation, SpaceX will land Falcon 9’s first stage on the “Of Course I Still Love You” droneship, which will be located in the Atlantic Ocean. Falcon 9’s fairing previously flew on the Transporter-1 mission.

Taking that to mean both halves. Is this the first dual reuse of a pair together?

Turnaround is pretty short as well.

Record turnaround, actually, at just 49 days.
Title: Re: Fairing reuse
Post by: ZachS09 on 03/18/2021 09:48 pm
With the arms being taken of Ms. Tree and Ms. Chief, they've given up on net catches for now. They're also refitting other SpaceX fleet ships to do water pickups as well, to increase catch fleet size.

Is there a tweet or some other source that flat-out says SpaceX is not doing anymore net catches as of today?
Title: Re: Fairing reuse
Post by: cscott on 03/19/2021 02:22 am
No.  There is some information on L2, but folks are just drawing conclusions from the removal of the arms from Ms Chief and Ms Tree.
Title: Re: Fairing reuse
Post by: AstroDave on 03/20/2021 12:49 am
  It has always been a bummer to see any fairing half come back beat up after the effort of trying to recover them. An assumption I made was that the damage was related to the impact of the water landings. Though a water landing can be rough, I now wonder how often the recovery and loading operation at sea might have stressed the fairings. There has been little material to go on in regards to these possible difficulties. No complaints here, just haven't seen much.
  Seeing the recent video clip posted by Gavin Cornwell of the Shelia Bordelon returning with a fairing half, it seems likely that SpaceX is doing some sea trials of the sophisticated crane that the ship uses. If the swell compensating technology of the crane allows for more successful fairing recoveries, that will be a big win! We may see Ms. Tree and Ms. Chief sporting versions of these types of cranes in the future.
Title: Re: Fairing reuse
Post by: su27k on 04/07/2021 06:09 pm
Confirms water recovery from now on:

https://twitter.com/elonmusk/status/1379744947453054981

Quote
Q: Are you abandoning the idea of reusing fairings entirely or will they still be fished out of the water at least to attempt reuse?

A: They will be recovered from the water & reused
Title: Re: Fairing reuse
Post by: wannamoonbase on 05/09/2021 01:04 am
I was checking out this thread today, it’s hard to believe that it’s been 6 years since they started talking about Fairing recovery.

It’s pretty normal now, but not 100% reliable.  SpaceX takes longer than Elon states to do things, but when they get things sorted they really take off with it. 

Tonights booster and dirty fairings are such a great example.

Maybe one day we’ll see a fairing that makes it to 10 flights, if Starship doesn’t replace F9 first.

Amazing, great job SpaceX.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 05/26/2021 07:00 pm
twitter.com/spacex/status/1397626461742190593

Quote
Today's flight will mark the 40th time SpaceX has reflown Falcon fairing halves since November 2019

https://twitter.com/spacex/status/1397626470776795138

Quote
This will also be the first time we fly a fairing half on its fifth mission
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 06/13/2021 11:14 pm
https://twitter.com/c_fletcher22/status/1404090074460004356

Quote
Even military payloads have the optimized fairing vent locations now. This was an “experiment” that started on Starlink missions last year. Notice how those vents are close to where the two halves meet? Now, it’s a lot harder for water to get into the fairing after splashdown.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 07/08/2021 08:57 pm
https://twitter.com/del_sailor/status/1413179388015874052

Quote
Wait for it.....

https://twitter.com/del_sailor/status/1413122562008174594

Quote
Tree rams fairing.
Title: Re: Fairing reuse
Post by: Welsh Dragon on 07/09/2021 09:35 am
Tweets don't work. What were they about?
Title: Re: Fairing reuse
Post by: ZChris13 on 07/09/2021 09:46 am
Tweets don't work. What were they about?
Being discussed here (https://forum.nasaspaceflight.com/index.php?topic=45083.msg2261368#msg2261368).
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 07/17/2021 11:53 am
https://twitter.com/julia_bergeron/status/1416364061479034884

Quote
Some new hardware is parked by the docks. Perhaps the fairing transport trailers have evolved? #SpaceX

Edit to add:

https://twitter.com/farryfaz/status/1367194648872116228

https://twitter.com/julia_bergeron/status/1416425590207483909

Quote
It seems I was busy with work and caretaking and missed their initial arrival. Great video!
Title: Re: Fairing reuse
Post by: su27k on 07/31/2021 06:01 am
https://twitter.com/SpaceXFleet/status/1421166804081299460

Quote
Believe in yourself and you can achieve anything. Don't stop at being a nosecone, become the boat you always wanted to be.

thank u fairing half for the motivation today o7 

Silly highlight clip from NSF Fleetcam. Live 24/7 here: https://youtu.be/gnt2wZBg89g

Title: Re: Fairing reuse
Post by: Adriano on 12/07/2021 07:33 pm
Great idea returning the fairings by leaving them attached to the first stage! How will Spacex respond to Roketlab move? Obviously the Falcon 9 business is threatened, but Spacex has plenty of options.

First option is to attach to the top of the Falcon 9 a shell enclosing the second stage and connecting the fairings to the booster. The diameter of the shell will be perhaps the same as the current fairings, allowing it to encase a second stage of the same size of the current second stage. The problem is the new rocket will be very thin and long, making a landing more complicated, and of course the weight penalty, reducing the max payload to orbit.

Second option is a variation of the Falcon Heavy, where the center rocket will be of greater diameter and shorter than the Falcon 9, so matching or exceeding the Rocketlab max payload.

A third option is to create s shorter version of the Superheavy booster and placing on top of it a shell that will encase payload and second stage and return home the fairings attached to the booster. The second stage will be ejected from the shell by compressed gas and will be powered by vacuum Merlin engines. So all the Raptors will be recovered and the Raptor production problem will be alleviated. This will add the complexity of adding to Starbase a kerosene fueling for the second stage. And, of course, FAA permit for frequent launches needs to be obtained for Boca Chicage.
Title: Re: Fairing reuse
Post by: wannamoonbase on 12/07/2021 08:51 pm
Great idea returning the fairings by leaving them attached to the first stage! How will Spacex respond to Roketlab move? Obviously the Falcon 9 business is threatened, but Spacex has plenty of options.

First option is to attach to the top of the Falcon 9 a shell enclosing the second stage and connecting the fairings to the booster. The diameter of the shell will be perhaps the same as the current fairings, allowing it to encase a second stage of the same size of the current second stage. The problem is the new rocket will be very thin and long, making a landing more complicated, and of course the weight penalty, reducing the max payload to orbit.

Second option is a variation of the Falcon Heavy, where the center rocket will be of greater diameter and shorter than the Falcon 9, so matching or exceeding the Rocketlab max payload.

A third option is to create s shorter version of the Superheavy booster and placing on top of it a shell that will encase payload and second stage and return home the fairings attached to the booster. The second stage will be ejected from the shell by compressed gas and will be powered by vacuum Merlin engines. So all the Raptors will be recovered and the Raptor production problem will be alleviated. This will add the complexity of adding to Starbase a kerosene fueling for the second stage. And, of course, FAA permit for frequent launches needs to be obtained for Boca Chicage.


I see almost zero reason for SpaceX to be wary of what Rocket labs is doing with Neutron.  Best of luck to them though, it's an interesting concept.


Neutron is years from flying then they have to learn how to fly it reliably and frequently..


Even if F9 and Neutron are flying at the same time, SpaceX has a flight rate that will have paid off the development of the vehicle and ware proficient at flying.  Basically, things are paid for, Neutron would have to be cheaper and fly more often to catch up to F9.


By that time that happen SpaceX maybe on the moon and flying Starship regularly, and Starship, does have a reuseable fairing attached to the upper stage. 
Title: Re: Fairing reuse
Post by: AC in NC on 12/07/2021 09:09 pm
Great idea returning the fairings by leaving them attached to the first stage! How will Spacex respond to Roketlab move? Obviously the Falcon 9 business is threatened, but Spacex has plenty of options.

First option is to attach to the top of the Falcon 9 a shell enclosing the second stage and connecting the fairings to the booster. The diameter of the shell will be perhaps the same as the current fairings, allowing it to encase a second stage of the same size of the current second stage. The problem is the new rocket will be very thin and long, making a landing more complicated, and of course the weight penalty, reducing the max payload to orbit.

Second option is a variation of the Falcon Heavy, where the center rocket will be of greater diameter and shorter than the Falcon 9, so matching or exceeding the Rocketlab max payload.

A third option is to create s shorter version of the Superheavy booster and placing on top of it a shell that will encase payload and second stage and return home the fairings attached to the booster. The second stage will be ejected from the shell by compressed gas and will be powered by vacuum Merlin engines. So all the Raptors will be recovered and the Raptor production problem will be alleviated. This will add the complexity of adding to Starbase a kerosene fueling for the second stage. And, of course, FAA permit for frequent launches needs to be obtained for Boca Chicage.

Are you serious?  If so, these are ludicrous.  If not, why waste everyone's time?  Is this funny for some reason that escapes me?  Either way, I'm not sure what you are after here.
Title: Re: Fairing reuse
Post by: Adriano on 12/09/2021 03:20 am
Great idea returning the fairings by leaving them attached to the first stage! How will Spacex respond to Roketlab move? Obviously the Falcon 9 business is threatened, but Spacex has plenty of options.

First option is to attach to the top of the Falcon 9 a shell enclosing the second stage and connecting the fairings to the booster. The diameter of the shell will be perhaps the same as the current fairings, allowing it to encase a second stage of the same size of the current second stage. The problem is the new rocket will be very thin and long, making a landing more complicated, and of course the weight penalty, reducing the max payload to orbit.

Second option is a variation of the Falcon Heavy, where the center rocket will be of greater diameter and shorter than the Falcon 9, so matching or exceeding the Rocketlab max payload.

A third option is to create s shorter version of the Superheavy booster and placing on top of it a shell that will encase payload and second stage and return home the fairings attached to the booster. The second stage will be ejected from the shell by compressed gas and will be powered by vacuum Merlin engines. So all the Raptors will be recovered and the Raptor production problem will be alleviated. This will add the complexity of adding to Starbase a kerosene fueling for the second stage. And, of course, FAA permit for frequent launches needs to be obtained for Boca Chicage.


I see almost zero reason for SpaceX to be wary of what Rocket labs is doing with Neutron.  Best of luck to them though, it's an interesting concept.


Neutron is years from flying then they have to learn how to fly it reliably and frequently..


Even if F9 and Neutron are flying at the same time, SpaceX has a flight rate that will have paid off the development of the vehicle and ware proficient at flying.  Basically, things are paid for, Neutron would have to be cheaper and fly more often to catch up to F9.


By that time that happen SpaceX maybe on the moon and flying Starship regularly, and Starship, does have a reuseable fairing attached to the upper stage.
Title: Re: Fairing reuse
Post by: Adriano on 12/09/2021 03:44 am
I fully concur it will take time before Spacex will see competition. But your second point is an accounting argument: Spacex by then will have fully amortized the cost of developing the Falcon 9 rocket and can afford without risking bankruptcy to cut the prices of launching satellites on Falcon 9 and hence can cut prices without reducing their reported profitability. True, if the only vehicle flying by then were the Falcon 9. But by then they will be also flying starship and Starship development costs will be far from being fully amortized when they are forced to cut launching fees across all their launching programs. And reducing the cash flows from satellite launching services will reduce their ability to finance flights to Mars…  Competition is always great for the market. Less so for the market leader.

Title: Re: Fairing reuse
Post by: wannamoonbase on 12/09/2021 03:02 pm
I fully concur it will take time before Spacex will see competition. But your second point is an accounting argument: Spacex by then will have fully amortized the cost of developing the Falcon 9 rocket and can afford without risking bankruptcy to cut the prices of launching satellites on Falcon 9 and hence can cut prices without reducing their reported profitability. True, if the only vehicle flying by then were the Falcon 9. But by then they will be also flying starship and Starship development costs will be far from being fully amortized when they are forced to cut launching fees across all their launching programs. And reducing the cash flows from satellite launching services will reduce their ability to finance flights to Mars…  Competition is always great for the market. Less so for the market leader.



Agreed that SpaceX will be able to go cheaper as more flights bring the cost per flight down.  But they may not do it until there is actual competition.  No need to drop sooner than needed.

Neutron seems like the only real competition on the horizon. 
Title: Re: Fairing reuse
Post by: DanClemmensen on 12/09/2021 03:18 pm
I fully concur it will take time before Spacex will see competition. But your second point is an accounting argument: Spacex by then will have fully amortized the cost of developing the Falcon 9 rocket and can afford without risking bankruptcy to cut the prices of launching satellites on Falcon 9 and hence can cut prices without reducing their reported profitability. True, if the only vehicle flying by then were the Falcon 9. But by then they will be also flying starship and Starship development costs will be far from being fully amortized when they are forced to cut launching fees across all their launching programs. And reducing the cash flows from satellite launching services will reduce their ability to finance flights to Mars…  Competition is always great for the market. Less so for the market leader.



Agreed that SpaceX will be able to go cheaper as more flights bring the cost per flight down.  But they may not do it until there is actual competition.  No need to drop sooner than needed.

Neutron seems like the only real competition on the horizon.
SpaceX has no economic incentive to reduce prices unless the market is elastic. If the market is elastic, providers with higher cost are going to be in trouble as SpaceX optimizes revenue by reducing price. SpaceX may have non-economic reasons to maintain a higher price. In particular they may need to keep the price high enough that other providers can survive in order to avoid being sanctioned for monopolistic practices.
Title: Re: Fairing reuse
Post by: freddo411 on 12/09/2021 03:24 pm
I fully concur it will take time before Spacex will see competition. But your second point is an accounting argument: Spacex by then will have fully amortized the cost of developing the Falcon 9 rocket and can afford without risking bankruptcy to cut the prices of launching satellites on Falcon 9 and hence can cut prices without reducing their reported profitability. True, if the only vehicle flying by then were the Falcon 9. But by then they will be also flying starship and Starship development costs will be far from being fully amortized when they are forced to cut launching fees across all their launching programs. And reducing the cash flows from satellite launching services will reduce their ability to finance flights to Mars…  Competition is always great for the market. Less so for the market leader.



Agreed that SpaceX will be able to go cheaper as more flights bring the cost per flight down.  But they may not do it until there is actual competition.  No need to drop sooner than needed.

Neutron seems like the only real competition on the horizon.
SpaceX has no economic incentive to reduce prices unless the market is elastic. If the market is elastic, providers with higher cost are going to be in trouble as SpaceX optimizes revenue by reducing price. SpaceX may have non-economic reasons to maintain a higher price. In particular they may need to keep the price high enough that other providers can survive in order to avoid being sanctioned for monopolistic practices.

Microsoft invested a huge amount of money in Apple in order to keep some plausible competition going.   I don’t think that is going to happen here. I think that the government will happily invest money or spend money on expensive launchers that are not part of SpaceX.  This will keep valid competitors going for SpaceX for at least a medium term
Title: Re: Fairing reuse
Post by: alugobi on 12/09/2021 04:10 pm
You wrote "valid", but "subsidized" might be more appropriate.  The Congress has its jobs/reelection/districting favorites. 
Title: Re: Fairing reuse
Post by: DanClemmensen on 12/10/2021 01:01 am
I fully concur it will take time before Spacex will see competition. But your second point is an accounting argument: Spacex by then will have fully amortized the cost of developing the Falcon 9 rocket and can afford without risking bankruptcy to cut the prices of launching satellites on Falcon 9 and hence can cut prices without reducing their reported profitability. True, if the only vehicle flying by then were the Falcon 9. But by then they will be also flying starship and Starship development costs will be far from being fully amortized when they are forced to cut launching fees across all their launching programs. And reducing the cash flows from satellite launching services will reduce their ability to finance flights to Mars…  Competition is always great for the market. Less so for the market leader.



Agreed that SpaceX will be able to go cheaper as more flights bring the cost per flight down.  But they may not do it until there is actual competition.  No need to drop sooner than needed.

Neutron seems like the only real competition on the horizon.
SpaceX has no economic incentive to reduce prices unless the market is elastic. If the market is elastic, providers with higher cost are going to be in trouble as SpaceX optimizes revenue by reducing price. SpaceX may have non-economic reasons to maintain a higher price. In particular they may need to keep the price high enough that other providers can survive in order to avoid being sanctioned for monopolistic practices.

Microsoft invested a huge amount of money in Apple in order to keep some plausible competition going.   I don’t think that is going to happen here. I think that the government will happily invest money or spend money on expensive launchers that are not part of SpaceX.  This will keep valid competitors going for SpaceX for at least a medium term
What does this mean? If the US government or any other entity chooses to subsidize launchers, SpaceX will benefit because they can charge slightly less than the subsidized price for any launches that are not subsidized. If the launch price is elastic for launches that are not sujbsidized, then SpaceX may choose a lower price. Eventually the subsidizing agency will give up, either due to external pressure or due to "cheating" as third parties use the cheaper solution  through "interesting" contract mechanisms.
Title: Re: Fairing reuse
Post by: Yggdrasill on 12/10/2021 12:40 pm
I fully concur it will take time before Spacex will see competition. But your second point is an accounting argument: Spacex by then will have fully amortized the cost of developing the Falcon 9 rocket and can afford without risking bankruptcy to cut the prices of launching satellites on Falcon 9 and hence can cut prices without reducing their reported profitability. True, if the only vehicle flying by then were the Falcon 9. But by then they will be also flying starship and Starship development costs will be far from being fully amortized when they are forced to cut launching fees across all their launching programs. And reducing the cash flows from satellite launching services will reduce their ability to finance flights to Mars…  Competition is always great for the market. Less so for the market leader.
You generally don't amortize development costs. It's pretty much always a part of R&D and comes right out of the gross profit. Since SpaceX is private we don't know exactly how they do their accounting, but it would surprise me greatly if development costs were defined as capex and then amortized instead of being included in R&D.

This means that there is no point in time where Falcon 9 becomes cheaper to launch just through accounting trickery. And there is similarly no such point in time for Starship either. Or Neutron, for that matter.
Title: Re: Fairing reuse
Post by: AC in NC on 12/10/2021 11:06 pm
This means that there is no point in time where Falcon 9 becomes cheaper to launch just through accounting trickery. And there is similarly no such point in time for Starship either. Or Neutron, for that matter.
And there's no chance at all that SpaceX is going to open up the R&D spigots trying to wrest some incremental savings from the F9 program because of anything Neutron does.
Title: Re: Fairing reuse
Post by: su27k on 06/12/2022 03:23 am
https://aviationweek.com/defense-space/space/spacex-building-airline-type-flight-ops-launch

Quote
SpaceX Building Airline-Type Flight Ops For Launch

June 10, 2022

FIRST IN A SERIES When SpaceX debuted the Block 5 version of its Falcon 9 rocket in 2018, it expected to fly the reusable boosters 10 times before taking them out of service for major refurbishment. But last summer, the company quietly moved the goalpost. “We got to 10 [flights] and the vehicles...

Under a photo of a fairing facility (maybe at Roberts Roads?), it is mentioned in this article that SpaceX currently has 36 fairing halves in its fleet, and the fairings are currently qualified to fly 10 times, and they plan to extend that to 15 times.
Title: Re: Fairing reuse
Post by: wannamoonbase on 06/12/2022 12:49 pm
https://aviationweek.com/defense-space/space/spacex-building-airline-type-flight-ops-launch

Quote
SpaceX Building Airline-Type Flight Ops For Launch

June 10, 2022

FIRST IN A SERIES When SpaceX debuted the Block 5 version of its Falcon 9 rocket in 2018, it expected to fly the reusable boosters 10 times before taking them out of service for major refurbishment. But last summer, the company quietly moved the goalpost. “We got to 10 [flights] and the vehicles...

Under a photo of a fairing facility (maybe at Roberts Roads?), it is mentioned in this article that SpaceX currently has 36 fairing halves in its fleet, and the fairings are currently qualified to fly 10 times, and they plan to extend that to 15 times.

Wow, if we see fairings fly 15 times the cost per flight, that would be $400K per flight (if a fairing set is still $6M)

These are significant savings per flight, especially with a weekly launch cadence. 
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 07/06/2022 06:09 pm
https://twitter.com/spaceoffshore/status/1544738462523424769

Quote
Doug has departed Port Canaveral with a big red.... thing... on the stern...!

A fairing is onboard for a potential sea trial. I wonder if they are testing a new recovery method. The way it's strapped on makes me think it's an inflatable of some sort.

nasaspaceflight.com/fleetcam
Title: Re: Fairing reuse
Post by: alugobi on 07/06/2022 06:12 pm
Maybe they need something to keep the fairing from banging the side of the hull when they're lifting it out.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 07/14/2022 07:32 pm
https://twitter.com/thejackbeyer/status/1547645511473045506

Quote
I *think* these might be the closest public pictures of the inside of a fairing half. This one appears to be SN179. @NASASpaceflight
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 07/26/2022 04:42 pm
https://twitter.com/gregscott_photo/status/1551965951989792768

Quote
SpaceX support ship Bob has spent the morning doing practice maneuvers with the fast boats & a fairing floating in the port. Never an dull moment in Port on Lab Padre's Gator Cam. #SpaceX #NASA
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 08/03/2022 05:21 pm
https://twitter.com/tgmetsfan98/status/1554874206319517696

Quote
SpaceX successfully recovered every fairing half that flew between May 2021 and June 2022.

In an effort to continue the success of the fairing reuse program, SpaceX is again experimenting with new recovery methods.

By Gavin Cornwell (@SpaceOffshore):

https://www.nasaspaceflight.com/2022/08/spacex-fairing-recovery/
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 08/10/2022 11:25 am
https://twitter.com/elonxnet/status/1557199482944634880

Quote
By my count, today's @SpaceX #Starlink launch marked the 100th fairing half reuse in only a few short years.

That's pretty huge and I feel like the whole fairing reuse aspect is largely underappreciated by the public.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 08/17/2022 12:56 am
Cross-post:

Off-load of recovered fairing viewed by NSF Fleetcam
Title: Re: Fairing reuse
Post by: Arb on 08/20/2022 09:30 am
Quote from: Elon Musk
Each fairing half is a fully capable reentry vehicle with its own thrusters, thermal protection, avionics & sensor suite

Source: twitter.com/elonmusk/status/1560711872344690691
Title: Re: Fairing reuse
Post by: rpapo on 08/20/2022 09:35 am
Quote from: Elon Musk
Each fairing half is a fully capable reentry vehicle with its own thrusters, thermal protection, avionics & sensor suite

Source: twitter.com/elonmusk/status/1560711872344690691
This actually makes me wonder how much this experience has fed into the Starship Bellyflop maneuver.  The aerodynamics are similar, albeit different in scale and speed.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 09/27/2022 07:33 pm
https://twitter.com/elonmusk/status/1574773851523022850

Quote
Falcon 9 fairing cam captures 2nd stage plume, booster entry burn & Earth in twilight
Title: Re: Fairing reuse
Post by: TrevorMonty on 09/27/2022 07:35 pm
Worth having the camera for shots like.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 10/15/2022 03:26 pm
https://twitter.com/spaceoffshore/status/1581302543216705536

Quote
Departure! Bob is heading out to sea for further testing of SpaceX's new inflatable fairing recovery net system. (The big red sausage on top deck)

This method of lifting fairings from the water was first trialled a few months ago.

Live via: nsf.live/spacecoast
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 10/23/2022 05:44 pm
Nice video of rig in action:

https://twitter.com/spaceoffshore/status/1584238940428861441

Quote
SpaceX is still testing out a new fairing recovery rig

Check out this real-time clip of how it responds to lifting the fairing load

Continues: nsf.live/spacecoast
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 11/06/2022 12:23 pm
https://twitter.com/onebadassmini/status/1589108458892451840

Quote
Space x fairings coming back from port today … 🚀
Title: Re: Fairing reuse
Post by: Barley on 11/06/2022 02:01 pm
Is there anywhere that keeps a running count on fairing reuse the same way they do for boosters?  What fraction of recent uses reused fairings?

Is fairing reuse now too boring to deserve reporting?

Title: Re: Fairing reuse
Post by: Coastal Ron on 11/06/2022 02:24 pm
Is there anywhere that keeps a running count on fairing reuse the same way they do for boosters?  What fraction of recent uses reused fairings?

Is fairing reuse now too boring to deserve reporting?

I don't know where I saw it, but someone is keeping track of fairings. Nice chart and everything you'd expect for SpaceX hardware tracking...  :D
Title: Re: Fairing reuse
Post by: scr00chy on 11/06/2022 02:47 pm
Is there anywhere that keeps a running count on fairing reuse the same way they do for boosters?  What fraction of recent uses reused fairings?

Is fairing reuse now too boring to deserve reporting?

Number of Fairing Half Reuses
127

Missions with at Least One Reused Fairing
65

Highest Number of Confirmed Reuses for a Particular Fairing
6

Share of F9/FH Launches with at Least One Reused Fairing (excl. Dragon)
11.11% (2019), 38% (2020), 68% (2021), 82.98% (2022)

https://www.elonx.net/spacex-statistics/#reuse
Title: Re: Fairing reuse
Post by: Nomadd on 11/06/2022 05:13 pm
Is there anywhere that keeps a running count on fairing reuse the same way they do for boosters?  What fraction of recent uses reused fairings?

Is fairing reuse now too boring to deserve reporting?

Number of Fairing Half Reuses
127

Missions with at Least One Reused Fairing
65

Highest Number of Confirmed Reuses for a Particular Fairing
6

Share of F9/FH Launches with at Least One Reused Fairing (excl. Dragon)
11.11% (2019), 38% (2020), 68% (2021), 82.98% (2022)

https://www.elonx.net/spacex-statistics/#reuse
Only 3 missions with mixed used/new halves. I wonder if there's a particular reason they don't like to mix them, or that's just the way it's done.
Title: Re: Fairing reuse
Post by: CuddlyRocket on 11/06/2022 08:08 pm
Has all the r&d costs for the re-use of fairings now been recovered in the savings from reusing fairings?
Title: Re: Fairing reuse
Post by: Exastro on 11/07/2022 03:00 am
Only 3 missions with mixed used/new halves. I wonder if there's a particular reason they don't like to mix them, or that's just the way it's done.

Speculation:  The new fairings are being flown mainly because a customer wants a new fairing, and no customers are interested in flying with just a half-new fairing.  New fairing halves are still being made, but only slowly, and they're being held back for customers willing to pay extra.
Title: Re: Fairing reuse
Post by: AmigaClone on 11/07/2022 05:36 am
Has all the r&d costs for the re-use of fairings now been recovered in the savings from reusing fairings?

The answer might depend on what all you consider a part of the r&d, and what falls under operational recoveries.

Considering the proposed number of launches, I can see the r&d either as being paid off by the savings, or within six months of doing so.
Title: Re: Fairing reuse
Post by: wannamoonbase on 11/07/2022 02:25 pm
Has all the r&d costs for the re-use of fairings now been recovered in the savings from reusing fairings?

The answer might depend on what all you consider a part of the r&d, and what falls under operational recoveries.

Considering the proposed number of launches, I can see the r&d either as being paid off by the savings, or within six months of doing so.

The cost per fairing half has crept up from $2.5M to $3M.  If the cost per use can come down to $500K per half, hopefully more, it looks to me like that cost of developing this capability has paid itself off.

Beyond simply paying for itself, it's doubtful that SpaceX could produce 60 full sets of fairings in a year to enable the current launch rate.  So like booster reuse, the ability to reuse hardware has enabled capabilities, like Starlink deployment, that would have been very difficult to manage without.

Which makes full reuse of a rocket system very exciting to anticipate.  What benefits and capabilities will be possible when full reuse and rapid flights are possible/routine.
Title: Re: Fairing reuse
Post by: su27k on 01/07/2023 04:49 am
https://twitter.com/Stuck4ger/status/1611420962099961856

Quote
@SpaceX faring migration season is surprisingly short as I saw these two flying south a few days ago but they are already on the final leg north returning to their roost. I expect it will soon be faring mating season.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 05/02/2023 09:23 pm
twitter.com/spacex/status/1653418134068662272

Quote
Stage separation at sunset, followed by second stage engine startup, and payload fairing deploy

https://twitter.com/spacex/status/1653418412918579203

Quote
This was the first time flight-proven fairings supported a Falcon Heavy mission, and it was the farthest downrange landing and recovery of fairings to-date at 1,200+ miles – nearly a third of the way to Africa!

https://twitter.com/spacex/status/1653509582046769156

Quote
Fairing reentry on the ViaSat-3 mission was the hottest and fastest we've ever attempted.  The fairings re-entered the atmosphere greater than 15x the speed of sound, creating a large trail of plasma in its wake
Title: Re: Fairing reuse
Post by: Jim on 05/02/2023 09:27 pm

https://twitter.com/spacex/status/1653509582046769156

Quote
Fairing reentry on the ViaSat-3 mission was the hottest and fastest we've ever attempted.  The fairings re-entered the atmosphere greater than 15x the speed of sound, creating a large trail of plasma in its wake

I saw the SES O3B fairings yesterday.  The logos were scorched.
Title: Re: Fairing reuse
Post by: joek on 05/02/2023 09:52 pm
Quote
Fairing reentry on the ViaSat-3 mission was the hottest and fastest we've ever attempted.  The fairings re-entered the atmosphere greater than 15x the speed of sound, creating a large trail of plasma in its wake

Would love to see what the reentry profile looks like.
Title: Re: Fairing reuse
Post by: Asteroza on 05/08/2023 03:22 am
Will the Viasat-3 FH fairings be reused? Or is that a bridge too far?
Title: Re: Fairing reuse
Post by: wannamoonbase on 05/08/2023 02:16 pm
Will the Viasat-3 FH fairings be reused? Or is that a bridge too far?

Good question, I'm wondering the same. 

I think their goal is to reuse them, or they wouldn't have gone through the trouble to recover them.

NSF community correct me if I'm wrong, but they looked like freshly coated fairing halves, but they each had previously flown.  So I was wondering if the coating they apply is an ablative shield.

If so, then maybe they just apply a thicker coating for these higher energy returns.

I believe it was the last Starlink flight where one half was on it's 9th flight and the other half was on it's 8th.  They are really making headway on the efficiencies of reusing the fairings.

If there was competition or if SpaceX had extra launch capacity to sell, it would be interesting to see what their per flight sales price would really be, because I think they already have room to lower prices, but there is no reason for them to do so at this point.
Title: Re: Fairing reuse
Post by: alugobi on 05/08/2023 04:37 pm
Will the Viasat-3 FH fairings be reused? Or is that a bridge too far?


I think their goal is to reuse them, or they wouldn't have gone through the trouble to recover them.
If they can, of course.  But I believe that they were certainly motivated to examine them at minimum.
Title: Re: Fairing reuse
Post by: wannamoonbase on 06/19/2023 02:18 am
I am still amazed at well fairing recovery is going. 

Todays Satria launch had a 7th and 9th fairing halves.

It’s going to be fun seeing how many flights they can get out of these. 

Maybe they last longer than the boosters. 
Title: Re: Fairing reuse
Post by: rsdavis9 on 06/19/2023 01:54 pm
These fairings are so durable.
I wonder if they could get one to reenter from orbit. A single person(well maybe 2 or 3 reentry vehicle.
for psn satria
meco 8400km/hr seco 27505km/hr fairing 9100km/hr
So roughly 9 times the energy (27500/9100)^2
So some ablative paint...
How hot does it get inside the fairing?
Title: Re: Fairing reuse
Post by: Nomadd on 06/19/2023 04:28 pm
How hot does it get inside the fairing?
I wondered about that. You know people have to be wondering if a person could ride one down.
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 06/23/2023 03:54 pm
New fairing reuse record just set for one fairing half:

https://twitter.com/spacex/status/1672267990241513472

Quote
Fairings deployed. Today's mission marks our first tenth flight of a fairing half
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 08/11/2023 05:25 am
New fairing record:

https://twitter.com/spacex/status/1689869627520864256

Quote
Fairings deployed. Today's mission marks our first 11th flight of a fairing half
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 08/30/2023 04:07 pm
https://twitter.com/sciguyspace/status/1696911323475419316

Quote
So it looks like @TurkeyBeaver dished on some of SpaceX's special sauce.

https://arstechnica.com/space/2023/08/spacexs-vp-of-launch-shares-the-companys-special-algorithm-for-innovation/

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Why did SpaceX give up on “catching” falling fairings? Its VP of launch explains
"You basically had this really awesome algorithm, this crazy automation."

by Eric Berger - Aug 30, 2023 3:29pm GMT

https://youtu.be/ZOWakxXjotg
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 09/12/2023 06:12 pm
Really get a sense of scale seeing the fairings being transported like this:

https://twitter.com/julia_bergeron/status/1701670641747812517

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SpaceX transporting the fairing halves recovered from Starlink 6-14 to be refurbished and flown again. Just another routine day on the Space Coast.
@NASASpaceflight 24/7 views:
nsf.live/spacecoast
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 09/13/2023 05:32 am
Testing fairing recovery yesterday:

https://twitter.com/spaceoffshore/status/1701712375521362319

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How to fish a SpaceX Falcon 9 fairing half ($3 million) from the water 👇

(via nsf.live/spacecoast)
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 09/27/2023 03:42 pm
Not a common occurrence:

https://twitter.com/spaceoffshore/status/1706998191420510416

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JRTI droneship delivered Falcon 9 back to Port Canaveral this morning just before daybreak.

Real story here is only one fairing half recovered :(

Can't even remember the last time SpaceX missed one on the East Coast!

nsf.live/spacecoast
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 11/04/2023 06:09 pm
In August SpaceX said (https://forum.nasaspaceflight.com/index.php?topic=37727.msg2513396#msg2513396) they’d had the first 11th use of a fairing half, now:

https://twitter.com/spacex/status/1720880148197826899

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SpaceX team aboard the recovery vessel Doug in the Atlantic securing a payload fairing half, which has supported 13 missions to-date, after last night's Starlink launch from Florida
Title: Re: Fairing reuse
Post by: brettly2021 on 12/10/2023 10:40 am
Looking at fairing re-entry video on  youtube
https://www.youtube.com/watch?v=Ke_QI7_UtA8 (https://www.youtube.com/watch?v=Ke_QI7_UtA8)
It seems pretty stable during the hot phase, once it gets to thicker air why dont they 'fly' or 'surf' the fairing to wherever they want? It should be possible to fly the fairing with full aerodynamic control, from those heights you could probably fly it to where-ever you want.
Some thoughts on how to steer the vehicle fairing:
1. first thought was control centre of gravity by having shifting weights that were on rails with rollers controlled by wires that loop around a bldc motor or similar
2. second thought was have some holes in the fairing which you can open/close allowing a stream of air to steer, furhter on that the stream of air through the holes could be directed.
3. final idea is have small flaps that come out once hit the thicker air, similar to starship, evern a small wing could be deployed. Space already have software for winglets and cylinder shape, some mods to that should suffice for fairing with flaps.
some pics to assist with the visualising the ideas:
Title: Re: Fairing reuse
Post by: brettly2021 on 12/10/2023 10:43 am
For testing drop the fairing from a decent height with one of the ideas above, have a guy with reomte control in helicopter chasing the fairing, and use the remote to steer/fly it, probably some skill required to fly it, then hone the system from there ( I hate the word iterate).
Title: Re: Fairing reuse
Post by: Nomadd on 12/10/2023 11:29 am
 Where are the handholds?
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 01/13/2024 08:18 am
From Elon’s SpaceX all-hands on Thursday:

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~$6M IN SAVINGS PER RECOVERY
REFLOWN FAIRINGS MORE THAN 300 TIMES
ATTITUDE-CONTROL THRUSTERS
STEERABLE PARACHUTE
Title: Re: Fairing reuse
Post by: wannamoonbase on 01/13/2024 06:01 pm
From Elon’s SpaceX all-hands on Thursday:

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~$6M IN SAVINGS PER RECOVERY
REFLOWN FAIRINGS MORE THAN 300 TIMES
ATTITUDE-CONTROL THRUSTERS
STEERABLE PARACHUTE

300 fairing halves at $2.5-3 million per half thats a cool $750-900M

That is not chump change.

Well done SpaceX, well done.
Title: Re: Fairing reuse
Post by: spacenuance on 02/07/2024 03:58 am
Fairing reuse update, February 6th 2024.

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Our flight leader fairing half has flown 15 times. Getting ready for its 16th flight in March. Also have a 14 flight unit and a 13 flight unit (which hopefully flies its 14th flight tonight if weather clears up).

https://twitter.com/edwards345/status/1755092120439038001 (https://twitter.com/edwards345/status/1755092120439038001)
Title: Re: Fairing reuse
Post by: FutureSpaceTourist on 03/10/2024 11:18 pm
Crosspost:

"These fairings recently supported USSF-124 only 25 days ago, marking the fastest turn-around time for fairing reusability to date"

https://twitter.com/SpaceX/status/1766964635725689199
Title: Re: Fairing reuse
Post by: jpo234 on 03/13/2024 02:43 pm
Seems SpaceX recently lost a fairing (https://www.reddit.com/r/whatisthisthing/comments/1bd0qk5/this_washed_up_on_a_beach_its_made_of_a_honeycomb/?utm_source=share&utm_medium=web3x&utm_name=web3xcss&utm_term=1&utm_content=share_button).

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This washed up on a beach. It's made of a honeycomb material covered in carbon fiber. It has wiring and some hydraulic tubing on one side. The part numbers don't turn up any results. It's attached to another piece via some kind of fabric material. It's flexible and quite heavy.
Title: Re: Fairing reuse
Post by: abaddon on 03/13/2024 05:32 pm
Seems SpaceX recently lost a fairing
Is there any indication it was "recently"?  Seems like this could be from any number of launches, stuff can float around quite a while before washing up wherever.
Title: Re: Fairing reuse
Post by: StraumliBlight on 03/13/2024 06:21 pm
Is there any indication it was "recently"?  Seems like this could be from any number of launches, stuff can float around quite a while before washing up wherever.

Part of CRS-4's interstage washed up in the Isles of Scilly (https://www.bbc.co.uk/news/uk-england-cornwall-34941462) after drifting 17 months and was completely covered in barnacles.

This fairing appears pretty clean so has probably only floated a few months tops.

https://twitter.com/TrescoIsland/status/670173601623052288
Title: Re: Fairing reuse
Post by: jpo234 on 03/13/2024 09:18 pm
Seems SpaceX recently lost a fairing
Is there any indication it was "recently"?  Seems like this could be from any number of launches, stuff can float around quite a while before washing up wherever.

▪️ It washed up on the Bahamas, so very close to Florida
▪️ No growth
▪️ It has a bag for the recovery chutes (see the last picture)