Author Topic: Fairing reuse  (Read 475850 times)

Offline cscott

  • Senior Member
  • *****
  • Posts: 2860
  • Liked: 1990
  • Likes Given: 664
Re: Fairing reuse
« Reply #1240 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.

Offline rpapo

  • Cybernetic Mole
  • Full Member
  • ****
  • Posts: 1131
  • Michigan, USA
  • Liked: 561
  • Likes Given: 439
Re: Fairing reuse
« Reply #1241 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.
An Apollo fanboy . . . fifty years ago.

Online deruch

  • Senior Member
  • *****
  • Posts: 2115
  • California
  • Liked: 1630
  • Likes Given: 3095
Re: Fairing reuse
« Reply #1242 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.
Shouldn't reality posts be in "Advanced concepts"?  --Nomadd

Offline Espen

  • Member
  • Posts: 1
  • Liked: 0
  • Likes Given: 0
Re: Fairing reuse
« Reply #1243 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?

Offline speedevil

  • Full Member
  • ****
  • Posts: 1928
  • Fife
  • Liked: 947
  • Likes Given: 1037
Re: Fairing reuse
« Reply #1244 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.

Offline Johnnyhinbos

  • Full Member
  • ****
  • Posts: 1294
  • Boston, MA
  • Liked: 1419
  • Likes Given: 209
Re: Fairing reuse
« Reply #1245 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?)
John Hanzl. Author, action / adventure www.johnhanzl.com

Offline rsdavis9

Re: Fairing reuse
« Reply #1246 on: 02/16/2018 12:39 PM »
lots of string. :)
With ELV best efficiency was the paradigm. The new paradigm is reusable, good enough, and commonality of design.
Same engines. Design once. Same vehicle. Design once. Reusable. Build once.

Online mme

  • Full Member
  • ****
  • Posts: 1212
  • Santa Barbara, CA, USA, Earth, Solar System, Milky Way Galaxy, Virgo Supercluster
  • Liked: 1459
  • Likes Given: 3974
Re: Fairing reuse
« Reply #1247 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.
Space is not Highlander.  There can, and will, be more than one.

Offline Alastor

  • Full Member
  • **
  • Posts: 263
  • Liked: 137
  • Likes Given: 306
Re: Fairing reuse
« Reply #1248 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. :-)

Online freddo411

  • Member
  • Posts: 36
  • Liked: 18
  • Likes Given: 65
Re: Fairing reuse
« Reply #1249 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.
« Last Edit: 02/16/2018 05:05 PM by freddo411 »

Offline speedevil

  • Full Member
  • ****
  • Posts: 1928
  • Fife
  • Liked: 947
  • Likes Given: 1037
Re: Fairing reuse
« Reply #1250 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.
« Last Edit: 02/16/2018 04:56 PM by speedevil »

Offline Space Ghost 1962

  • Senior Member
  • *****
  • Posts: 2783
  • Whatcha gonna do when the Ghost zaps you?
  • Liked: 2893
  • Likes Given: 2249
Re: Fairing reuse
« Reply #1251 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.
« Last Edit: 02/16/2018 07:55 PM by Space Ghost 1962 »

Offline speedevil

  • Full Member
  • ****
  • Posts: 1928
  • Fife
  • Liked: 947
  • Likes Given: 1037
Re: Fairing reuse
« Reply #1252 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)

Offline Space Ghost 1962

  • Senior Member
  • *****
  • Posts: 2783
  • Whatcha gonna do when the Ghost zaps you?
  • Liked: 2893
  • Likes Given: 2249
Re: Fairing reuse
« Reply #1253 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.

Online deruch

  • Senior Member
  • *****
  • Posts: 2115
  • California
  • Liked: 1630
  • Likes Given: 3095
Re: Fairing reuse
« Reply #1254 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.
Shouldn't reality posts be in "Advanced concepts"?  --Nomadd

Online freddo411

  • Member
  • Posts: 36
  • Liked: 18
  • Likes Given: 65
Re: Fairing reuse
« Reply #1255 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

Online meberbs

  • Full Member
  • ****
  • Posts: 1544
  • Liked: 1409
  • Likes Given: 350
Re: Fairing reuse
« Reply #1256 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.

Offline Raul

  • Full Member
  • *
  • Posts: 194
  • Ústí nad Orlicí, CZECH
  • Liked: 356
  • Likes Given: 29
Re: Fairing reuse
« Reply #1257 on: 02/17/2018 10:50 PM »
According to today's photos is high speed fairing boat Mr.Steven ready with net attached for recovery attempt of upgraded fairing.

Offline speedevil

  • Full Member
  • ****
  • Posts: 1928
  • Fife
  • Liked: 947
  • Likes Given: 1037
Re: Fairing reuse
« Reply #1258 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 ...
:)

Offline testguy

  • Full Member
  • *
  • Posts: 177
  • Clifton, Virginia
  • Liked: 140
  • Likes Given: 179
Re: Fairing reuse
« Reply #1259 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!

Tags: