NASASpaceFlight.com Forum

SpaceX Vehicles and Missions => SpaceX Reusability => Topic started by: bioelectromechanic on 09/29/2016 12:11 pm

Title: Falcon 9 (Future) speculation
Post by: bioelectromechanic on 09/29/2016 12:11 pm
During the recent ITS presentation, Elon mentioned an upcoming F9 upgrade, slated for "next year". What do you guys think the upgrade will be?

I'll throw out a few possibilities:
* fairing reuse
* raptor on F9
* carbon fiber tanks / structure
* removal of legs from first stage due to sufficient landing accuracy.
* s2 orbital refueling capability
Title: Re: Falcon 9 v1.2 speculation
Post by: MikeAtkinson on 09/29/2016 12:25 pm
Next year is too soon for Raptor.

They have only just test fired it for the first time. There are probably a year or more of tests to come, perhaps with several versions for gradual improvements.

Then there is a qualification engine, with perhaps 3 months of qualification tests.

Then the first production engines with acceptance tests.

Then production of the first Raptor stage, qualification and/or acceptance tests.

Then integration with the other stage.

All that is 2.5 years if all goes well before the first Raptor stage is launched.
Title: Re: Falcon 9 v1.2 speculation
Post by: Jarnis on 09/29/2016 12:35 pm
My guess; just optimization for re-use. Saving weight on bits that do not need to be as sturdy (based on actual returned boosters), adding weight on bits that need to be tougher so they do not need to be replaced after flight and/or replaced so often.

All kinds of things would probably seem obvious once you can carefully study a flown booster...
Title: Re: Falcon 9 v1.2 speculation
Post by: Jim on 09/29/2016 12:36 pm
During the recent ITS presentation, Elon mentioned an upcoming F9 upgrade, slated for "next year". What do you guys think the upgrade will be?

I'll throw out a few possibilities:
* fairing reuse


I removed the ones that are not going to happen
Title: Re: Falcon 9 v1.2 speculation
Post by: Jim on 09/29/2016 12:37 pm
Raptor is not going to fly on F9
Title: Re: Falcon 9 v1.2 speculation
Post by: bioelectromechanic on 09/29/2016 12:53 pm
can you explain the rationale?

p.s
also possible that by upgrade he meant the F9H.
Title: Re: Falcon 9 v1.2 speculation
Post by: Jim on 09/29/2016 12:57 pm
can you explain the rationale?

p.s
also possible that by upgrade he meant the F9H.

Too many changes to vehicle,  launch complex and operations.   It loses all commonality with the first stage which is a selling point of the F9/FH.  And too high of thrust.

There is no need for it
Title: Re: Falcon 9 v1.2 speculation
Post by: MikeAtkinson on 09/29/2016 01:01 pm
* Max thrust Merlin 1D
* Changes to 2nd stage to allow more burns
* Changes to 2nd stage to extend duration
* Lengthen 2nd stage (possible, but I think unlikely)
* Changes to 1st stage to improve reusability
Title: Re: Falcon 9 v1.2 speculation
Post by: spacenut on 09/29/2016 01:05 pm
I would think changes to second stage to avoid the problems with the helium system.   The first stage seems fine as is, with maybe some minor improvements.  The second stage lost a cargo to ISS, due to helium tank struts.  They are now looking at something that may have happened with the helium system.  They may place the helium tanks in the kerosene tanks like the first stage. 
Title: Re: Falcon 9 v1.2 speculation
Post by: Hobbes-22 on 09/29/2016 01:12 pm
I object to the use of 'v1.2' for the next version of Falcon.

SpaceX may call the current version 'FT', but they use the moniker 'v1.2' internally. Various websites (http://www.spacelaunchreport.com/falcon9ft.html) use that label as well.

The fact there will be another version of the F9 shows that the name 'Full Thrust' was not the best choice.

I suggest using 'v1.3' for the next version.
Title: Re: Falcon 9 v1.2 speculation
Post by: Jim on 09/29/2016 01:14 pm
I would think changes to second stage to avoid the problems with the helium system.   The first stage seems fine as is, with maybe some minor improvements.  The second stage lost a cargo to ISS, due to helium tank struts.  They are now looking at something that may have happened with the helium system.  They may place the helium tanks in the kerosene tanks like the first stage. 

There are already He bottles in the RP-1 tanks for both stages.
Title: Re: Falcon 9 v1.2 speculation
Post by: Falcon H on 09/29/2016 02:27 pm
Next year is too soon for Raptor.

They have only just test fired it for the first time. There are probably a year or more of tests to come, perhaps with several versions for gradual improvements.
And it was a scaled down version at that.
Title: Re: Falcon 9 v1.2 speculation
Post by: TrueBlueWitt on 09/29/2016 02:54 pm
Next year is too soon for Raptor.

They have only just test fired it for the first time. There are probably a year or more of tests to come, perhaps with several versions for gradual improvements.
And it was a scaled down version at that.

Has that been confirmed?
Full sized Raptor is about the same size as a Merlin.. So I can't imagine them going with a sub-scale version.
Not to mention that looks about the size  of what we saw on the test stand.
Title: Re: Falcon 9 v1.2 speculation
Post by: whitelancer64 on 09/29/2016 03:01 pm
I object to the use of 'v1.2' for the next version of Falcon.

SpaceX may call the current version 'FT', but they use the moniker 'v1.2' internally. Various websites (http://www.spacelaunchreport.com/falcon9ft.html) use that label as well.

The fact there will be another version of the F9 shows that the name 'Full Thrust' was not the best choice.

I suggest using 'v1.3' for the next version.

I concur, this would be Falcon 9 v1.3
Title: Re: Falcon 9 v1.2 speculation
Post by: The Amazing Catstronaut on 09/29/2016 04:49 pm
Next year is too soon for Raptor.

They have only just test fired it for the first time. There are probably a year or more of tests to come, perhaps with several versions for gradual improvements.
And it was a scaled down version at that.

You don't know this.
Title: Re: Falcon 9 v1.2 speculation
Post by: S.Paulissen on 09/29/2016 04:58 pm
In fact, most evidence so far points to it being full sized, not scaled down.

EDIT: Reworded to reflect appropriate level of certainty.
Title: Re: Falcon 9 v1.2 speculation
Post by: edkyle99 on 09/29/2016 10:15 pm
I object to the use of 'v1.2' for the next version of Falcon.

SpaceX may call the current version 'FT', but they use the moniker 'v1.2' internally. Various websites (http://www.spacelaunchreport.com/falcon9ft.html) use that label as well.

The fact there will be another version of the F9 shows that the name 'Full Thrust' was not the best choice.

I suggest using 'v1.3' for the next version.

I concur, this would be Falcon 9 v1.3
SpaceX announced a few months back that Falcon 9 would soon start flying with up-thrusted Merlins.  That may be part of what Elon was talking about, but I think that most engineering effort is going into Falcon Heavy, which may also have been what he was talking about.  The current rocket is Falcon 9 v1.2, officially.  My guess is that the ultimate improved thrust version might keep that name, because little else will have changed.  "Full Thrust" was a name initially given that has been left behind without fanfare. 

 - Ed Kyle
Title: Re: Falcon 9 v1.2 speculation
Post by: HVM on 09/29/2016 11:20 pm
And it was a scaled down version at that.
By OSHA rule 1910.23, guardrail height is 42" = ~1.1m, gives ~0.91m diameter of the Bell end/engine throat. Either it's half size or without nozzle...
Title: Re: Falcon 9 v1.2 speculation
Post by: RotoSequence on 09/29/2016 11:22 pm
And it was a scaled down version at that.
By OSHA rule 1910.23, guardrail height is 42" = ~1.1m, gives ~0.91m diameter of the Bell end/engine throat. Either it's half size or without nozzle...

I'd go with "nozzle-less," especially if they're starting their design and testing process with the vacuum engine. Considering their contract with the US Air Force, I'd consider it likely.

Good call with the OSHA regulations.  :D
Title: Re: Falcon 9 v1.2 speculation
Post by: TrevorMonty on 09/30/2016 02:21 am
Jim's adamant that Raptor is not fly on a F9/H US. I very much doubt Air force would help fund Raptof it if there was no possibility of it flying.

Either way it still a 1-2 years away from being flight ready.
Title: Re: Falcon 9 v1.2 speculation
Post by: savuporo on 09/30/2016 02:34 am
Quote
* automatic fast fire supression system
If i were to bet..
Title: Re: Falcon 9 v1.2 speculation
Post by: Jim on 09/30/2016 03:30 am
Jim's adamant that Raptor is not fly on a F9/H US. I very much doubt Air force would help fund Raptof it if there was no possibility of it flying.

Either way it still a 1-2 years away from being flight ready.

It would be longer

and the Air Force has no need for it.
Title: Re: Falcon 9 v1.2 speculation
Post by: dorkmo on 09/30/2016 04:31 am
i think they might swap out the dance floor heat blankets for some type of flexible metal petal system around each merlin. to minimize refurb work.

https://en.wikipedia.org/wiki/Thrust_vectoring#/media/File:Sukhoi_Su-35S_07_RED_PAS_2013_07_cutout.jpg
Title: Re: Falcon 9 v1.2 speculation
Post by: HVM on 09/30/2016 08:47 am
Jim's adamant that Raptor is not fly on a F9/H US. I very much doubt Air force would help fund Raptof it if there was no possibility of it flying.

Either way it still a 1-2 years away from being flight ready.

It would be longer

and the Air Force has no need for it.

Air Force give money out for lolz and giggles then? Raptor upper stage, with solar panels, can do everything that Centaur/Aces can. So I guess Air Force would be interested...
Title: Re: Falcon 9 v1.2 speculation
Post by: FinalFrontier on 09/30/2016 08:53 am
And it was a scaled down version at that.
By OSHA rule 1910.23, guardrail height is 42" = ~1.1m, gives ~0.91m diameter of the Bell end/engine throat. Either it's half size or without nozzle...
Chamber throat no nozzle.
Title: Re: Falcon 9 v1.2 speculation
Post by: FinalFrontier on 09/30/2016 08:56 am
can you explain the rationale?

p.s
also possible that by upgrade he meant the F9H.

Too many changes to vehicle,  launch complex and operations.   It loses all commonality with the first stage which is a selling point of the F9/FH.  And too high of thrust.

There is no need for it
Then why did USAF ask for it? Or are they referring to a different methane upper stage?
Interested in your input here, I don't disagree with you despite what I said in the other thread a few days ago, but something is not adding up here. Besides that USAF thing, why maintain duplicate engine production lines? It's counter-intuitive.

I do agree, however, that whatever upgrade is occurring next summer would not be a raptor US or 1st stage, even if that is the ultimate plan it would be way too soon. And it would entirely negate the purpose of FH existing at all.

So again, something doesn't make sense here.
Title: Re: Falcon 9 v1.2 speculation
Post by: wannamoonbase on 09/30/2016 02:25 pm
Current F9/FH Engineering efforts I think are likley are:

1) Uprated Merlins
2) FH
3) Cost and efficiency improvements in manufacturing
4) Improvements for reuse-ability (now that they've recovered a few)

The F9 is already a very capable vehicle.  I don't see too many big surprises coming.
Title: Re: Falcon 9 v1.2 speculation
Post by: Alastor on 09/30/2016 04:08 pm
One thing is for sure, they have done experiments on fairing recovery.
So either they have determined it to be not doable/too expensive or it is still on the radar.

I however don't think they would be that close to finishing work on that (we have never seen them get back with one, even a broken one). So this "final upgrade" can't be that one.

Actually, I think by "final upgrade", they mean "final major upgrade". There may still be future minor upgrades and fairing recovery is probably part of that.

My guess would be finalizing work to allow more easy and rapid recovery.
Maybe also making He systems more robust in light of recent (and less recent) events ? But again, that would be a minor upgrade, unless they determine they have to overhaul the whole thing, but that is unlikely.
Title: Re: Falcon 9 v1.2 speculation
Post by: Elmar Moelzer on 09/30/2016 11:23 pm
Well, I would think that either they will work more on upper stage reusability, or they will optimize the US and M-Vac for cost. Probably reduce its margins and optimize manufacturing for it being as cheap as possible since it will be expendable. On the upper stage, every pound saved is a pound more payload. So that could pay off.
I would expect them to do the same for the fairing. Either work towards reusing it or further optimizing it for cost.
First stage will see improvements based on the lessons learned from the currently recovered boosters. I have not heard any details about their test results. So it is hard to say what they will be. There will probably be reduced margins in places where the wear turned out to be less than expected and improved margins in places where the wear was worse (if any of those exist?). The grid fins seemed to have suffered some heat damage occasionally. So those might be a good target.
Maybe some improved thermal protection near the bottom to reduce maintenance.
I doubt that they can get much more thrust out of the Merlins. The last version was already called FT (Full Thrust). So I guess that means that they used all the margins back then already.
Title: Re: Falcon 9 v1.2 speculation
Post by: Toast on 09/30/2016 11:29 pm
I doubt that they can get much more thrust out of the Merlins. The last version was already called FT (Full Thrust). So I guess that means that they used all the margins back then already.

Elon mentioned (https://twitter.com/elonmusk/status/726557903205756928) back in April that they are actually upgrading Merlin thrust again.

Quote
F9 thrust at liftoff will be raised to 1.71M lbf later this year. It is capable of 1.9M lbf in flight...Basically current, but higher throttle setting. Good performance of recent launches allows us to reduce 3 sigma reserve margin...No physical changes to the engine. This thrust increase is based on delta qual tests. It is just tougher than we thought.
Title: Re: Falcon 9 v1.2 speculation
Post by: Elmar Moelzer on 10/01/2016 01:04 am
I doubt that they can get much more thrust out of the Merlins. The last version was already called FT (Full Thrust). So I guess that means that they used all the margins back then already.

Elon mentioned (https://twitter.com/elonmusk/status/726557903205756928) back in April that they are actually upgrading Merlin thrust again.

Quote
F9 thrust at liftoff will be raised to 1.71M lbf later this year. It is capable of 1.9M lbf in flight...Basically current, but higher throttle setting. Good performance of recent launches allows us to reduce 3 sigma reserve margin...No physical changes to the engine. This thrust increase is based on delta qual tests. It is just tougher than we thought.
I stand corrected... and "whoa!"
Title: Re: Falcon 9 v1.2 speculation
Post by: Johnnyhinbos on 10/01/2016 10:41 am
My expectation is twofold:

- go to the uprated, 1.9Mlb thrust. (Will this stretch the stages again?) Not only larger payload potential, but also allows more RTLS options.

- add planned refinements with regards to reusability. It been a firm belief of mine that SpaceX had a series of mods they would build into the booster, but didn't want these more expensive adders on a booster that hid a high probability of getting destroyed on landing. Now with higher confidence they can add them in. I mean things like higher grade fittings and more esoteric aka, expensive TPS tech, etc.

- and maybe - just maybe, but I doubt it, add bottom of booster fine steering RCS , alignment fins and no legs, along with an ASDS with capture system for legless landing testing.
Title: Re: Falcon 9 v1.2 speculation
Post by: CorvusCorax on 10/02/2016 10:28 pm
I'd speculate there *could* be a raptor upper stage for F9/FH but I don't think this is the announced change

Things that point at a eventual Raptor upper stage:
* Contract with airforce that explicitly mentiones mengine development for Falcon upper stage.
* Opportunity to gather flight heritage and data with a *cheap* vehicle as opposed to ITS prototypes
* Opportunity to experiment with methane handling at pads
* Capabilities of such a stage are alluring ( long coasts, high ISP -> direct GEO insertion for DOD payloads, deep space probes, ... (anything centaur can do, I cando cheaper... ;) )

But I highly doubt this would be the announced upgrade, because

* 2017 is too early for raptor, scheduled for 2018
* Stage would be more expensive than merlin US
* Additional performance is overkill for vast majority of manifested Falcon payloads
* Raptor vac needs a 'clipped nozzle' to fit in Falcon and would not reach its full potential

SpaceX tests as they fly, as such I think some early flying raptors using a modified US on a Falcon booster might be a thing.
But it would likely not be SpaceX default "workhorse" configuration.
Title: Re: Falcon 9 v1.2 speculation
Post by: AncientU on 10/03/2016 12:03 am
You can add refuelable... great capability for high energy BEO deliveries.
Title: Re: Falcon 9 v1.2 speculation
Post by: Tonioroffo on 10/09/2016 12:12 pm
Raptor on F9 is basically a new launch vehicle.  I think, except for more thrust, there will only be small tweaks for reliability and ease of operations.  F9 needs to become the reliable workhorse to bring in the money for the Mars project.
Title: Re: Falcon 9 (Future) speculation
Post by: RyanC on 10/22/2016 11:08 pm
Could they cheaply convert Falcon 9 to Methane? It all depends on how much changes you have to do to Merlin to make it work on Methane.
Title: Re: Falcon 9 (Future) speculation
Post by: ethan829 on 10/23/2016 10:34 am
Could they cheaply convert Falcon 9 to Methane? It all depends on how much changes you have to do to Merlin to make it work on Methane.


It would require pretty significant modifications to the tankage due to the different densities of RP-1 and methane.
Title: Re: Falcon 9 (Future) speculation
Post by: hkultala on 10/23/2016 10:59 am
Could they cheaply convert Falcon 9 to Methane? It all depends on how much changes you have to do to Merlin to make it work on Methane.

All the fuel pipes and pumps would need to be considerably bigger. Would require major redesign or the engine,
 
Probably better to go all the way to high-isp FFSC mini-raptor then than wasting a lot of R&D for low-isp GG methane engine, when the major motivation might be the reuse of the second stage for high-energy GTO missions.
Title: Re: Falcon 9 (Future) speculation
Post by: R7 on 10/23/2016 11:26 am
* reliability
Title: Re: Falcon 9 (Future) speculation
Post by: Kosmos2001 on 10/23/2016 02:37 pm
Could they cheaply convert Falcon 9 to Methane? It all depends on how much changes you have to do to Merlin to make it work on Methane.


It would require pretty significant modifications to the tankage due to the different densities of RP-1 and methane.

And consequently new MCI analyses for new control and so on.
Title: Re: Falcon 9 v1.2 speculation
Post by: SweetWater on 10/23/2016 05:00 pm
can you explain the rationale?

p.s
also possible that by upgrade he meant the F9H.

Too many changes to vehicle,  launch complex and operations.   It loses all commonality with the first stage which is a selling point of the F9/FH.  And too high of thrust.

There is no need for it
Then why did USAF ask for it? Or are they referring to a different methane upper stage?
Interested in your input here, I don't disagree with you despite what I said in the other thread a few days ago, but something is not adding up here. Besides that USAF thing, why maintain duplicate engine production lines? It's counter-intuitive.

I do agree, however, that whatever upgrade is occurring next summer would not be a raptor US or 1st stage, even if that is the ultimate plan it would be way too soon. And it would entirely negate the purpose of FH existing at all.

So again, something doesn't make sense here.

The USAF awarded contracts to both SpaceX (for the aforementioned Raptor testing)and Orbital ATK (for development of the Common Booster Segment, GEM 63XL strap-on motor, and an extendable nozzle for the BE-3U) Source at Parabolic Arc here: http://www.parabolicarc.com/2016/01/13/air-force-awards-rocket-contracts-spacex-orbital-atk/ (http://www.parabolicarc.com/2016/01/13/air-force-awards-rocket-contracts-spacex-orbital-atk/).  Initial awards were $33.6 million for SpaceX and $46.9 million for Orbital ATK, although I believe there were options in both contracts for addition funding. Both contracts provided USAF funds to supplement internal funding from both companies.

I'm not involved in the spaceflight industry the way many on this board are, so I admit this is merely speculation on my part, but this reads to me like the USAF keeping its options open. They know that the launch industry is changing fast, and they know that it is difficult to predict where the industry will be in 10 years, so they are helping to fund a few promising projects. Maybe they'll bear fruit, maybe not, but it establishes the Air Force as a stakeholder in the project, which can only be a good thing if the project works out as planned.

Also, while $33 million seems like a lot of money to most of us, let's keep in mind that the USAF budget for 2016 was $161 billion (source: https://www.washingtonpost.com/news/checkpoint/wp/2016/02/09/winners-and-losers-in-the-pentagons-new-budget/ (https://www.washingtonpost.com/news/checkpoint/wp/2016/02/09/winners-and-losers-in-the-pentagons-new-budget/). The initial award to SpaceX was 1/4800th of the total USAF budget this year, which is literally the equivalent of me impulse buying a 6 pack of craft beer.

Of course, if the Air Force funded engines the way I buy beer, there'd be A LOT more engine development contracts in this country...
Title: Re: Falcon 9 (Future) speculation
Post by: gongora on 10/24/2016 12:30 am
Elon's answer about F9 upgrade from the /r/spacex Reddit AMA (https://www.reddit.com/r/spacex/comments/590wi9/i_am_elon_musk_ask_me_anything_about_becoming_a/d94v8p8/?context=3):
Quote
Question from /u/FoxhoundBat:

    Overall is the landing architecture of ITS booster and distances needed to be covered to be same as Falcon 9’s? Boostback, re-entry burn, landing burn?

    Could you give us nuggets on what changes the ”final” Falcon 9 version (”v1.3”) you mentioned will have? Uprated engines obviously from 170k to 190k lbf, but what else? Is it mostly geared towards reusabilty over performance?

    Gwynne mentioned 2 weeks ago that F9 v1.2 will be reused only once or twice while ”v1.3” should be reused up to 10 times. Can you talk about what are the limiting factors for Falcon 9 reuse?

Answer from /u/ElonMuskOfficial:

The big booster will have an easier time of things than Falcon, as the mass ratio of the stages is lower and it will have lower density. Net result is that it won't come in quite as hot and fast as Falcon, so Falcon should be a bounding case on the big booster.

Final Falcon 9 has a lot of minor refinements that collectively are important, but uprated thrust and improved legs are the most significant.

Actually, I think the F9 boosters could be used almost indefinitely, so long as there is scheduled maintenance and careful inspections. Falcon 9 Block 5 -- the final version in the series -- is the one that has the most performance and is designed for easy reuse, so it just makes sense to focus on that long term and retire the earlier versions. Block 5 starts production in about 3 months and initial flight is in 6 to 8 months, so there isn't much point in ground testing Block 3 or 4 much beyond a few reflights.

Title: Re: Falcon 9 (Future) speculation
Post by: envy887 on 10/24/2016 03:44 am
* reliability

Merlin has flown almost 300 times, hard to beat it's reliability.
Title: Re: Falcon 9 (Future) speculation
Post by: R7 on 10/24/2016 06:16 am
* reliability

Merlin has flown almost 300 times, hard to beat it's reliability.
Topic says Falcon 9, not Merlin.
Title: Re: Falcon 9 (Future) speculation
Post by: envy887 on 10/24/2016 01:19 pm
* reliability

Merlin has flown almost 300 times, hard to beat it's reliability.
Topic says Falcon 9, not Merlin.

Falcon 9 without Merlin is no longer Falcon 9 but a whole new LV. Might be more reliable, but it will take 5-10 years to prove it.
Title: Re: Falcon 9 (Future) speculation
Post by: spacenut on 10/24/2016 02:40 pm
They will not use Raptor on the first stage.  First stage works great as is.  Second stage is where the helium problems are and a wider second stage with a Raptor vacuum engine would greatly increase the capability of the Falcon 9.  Someone figured in expendable mode a single Falcon 9 with a single Raptor based second stage could get 28 tons to LEO and 90 tons with fully expendable Falcon Heavy.  So either major improvements for quick turn around launches with improved helium handling of second stage, or eventually a Raptor based second stage. 
Title: Re: Falcon 9 (Future) speculation
Post by: hkultala on 10/24/2016 03:03 pm
About the F9 blocks..

v1.0 == block 1

but then, what are blocks 2, 3 and 4?

option a)
block 2 is v1.1
block 3 is v1.1 with legs?
block 4 is the current "almost full thrust" version.

option b)
block 2 is v1.1
block 3 is  the current "almost full-thrust" version.
block 4 is some upcoming improvement, now in production but not flown, and block 5 is later improvement

option c)
block 2 was the cancelled "1.0 full thrust" with upgraded merlin "1C+" engines
block 3 was 1.1
block 4 is current "almost full-thrust" version

option d)
something else, what?
Title: Re: Falcon 9 (Future) speculation
Post by: R7 on 10/24/2016 05:52 pm
Falcon 9 without Merlin is no longer Falcon 9 but a whole new LV. Might be more reliable, but it will take 5-10 years to prove it.
Again, topic is Falcon 9. F9, the whole system, needs to become more reliable. Merlin reliability isn't current problem. The "weird" reasons causing rest of the vehicle to occassionally explode need to go away.
Title: Re: Falcon 9 (Future) speculation
Post by: tleski on 10/26/2016 02:10 pm
About the F9 blocks..

v1.0 == block 1

(...)

We don't even know that for sure.
Some people suggested that block1 through 5 are subvariants of Flacon 9 FT and I think there is some support for this in Musk's Reddit statement.
Title: Re: Falcon 9 (Future) speculation
Post by: whitelancer64 on 10/26/2016 03:27 pm
About the F9 blocks..

v1.0 == block 1

(...)

We don't even know that for sure.
Some people suggested that block1 through 5 are subvariants of Flacon 9 FT and I think there is some support for this in Musk's Reddit statement.

The Falcon 9 User's Guide from 2009, refers to what we now call the "1.0" as the "Block 1"

http://www.nasahunch.com/wp-content/uploads/2014/09/Falcon9UsersGuide_2009.pdf
Title: Re: Falcon 9 (Future) speculation
Post by: tleski on 10/26/2016 03:52 pm
About the F9 blocks..

v1.0 == block 1

(...)

We don't even know that for sure.
Some people suggested that block1 through 5 are subvariants of Flacon 9 FT and I think there is some support for this in Musk's Reddit statement.

The Falcon 9 User's Guide from 2009, refers to what we now call the "1.0" as the "Block 1"

http://www.nasahunch.com/wp-content/uploads/2014/09/Falcon9UsersGuide_2009.pdf

It is also possible that each version of Falcon 9 has its own blocks (revisions). The only boosters recovered so far were all FT. Musk was mentioning that there is no point of reflying block 3 or 4 too many times, they wait for block 5, which points to them being versions of FT. We won't know unless SpaceX people officially confirm this.
Title: Re: Falcon 9 (Future) speculation
Post by: jpo234 on 10/26/2016 04:14 pm
An interesting comment from a SpaceX employee in the Reddit thread:

We haven't even flown all the block 3s yet.
 (https://www.reddit.com/r/spacex/comments/591rj1/rspacex_elon_musk_ama_answers_discussion_thread/d956whr/)

I... I actually don't know how the blocks line up with the version numbers. Version numbers are pretty much strictly used outside the company and by Elon. (https://www.reddit.com/r/spacex/comments/591rj1/rspacex_elon_musk_ama_answers_discussion_thread/d9575v5/)
Title: Re: Falcon 9 (Future) speculation
Post by: envy887 on 10/26/2016 04:22 pm
About the F9 blocks..

v1.0 == block 1

(...)

We don't even know that for sure.
Some people suggested that block1 through 5 are subvariants of Flacon 9 FT and I think there is some support for this in Musk's Reddit statement.

The Falcon 9 User's Guide from 2009, refers to what we now call the "1.0" as the "Block 1"

http://www.nasahunch.com/wp-content/uploads/2014/09/Falcon9UsersGuide_2009.pdf

It is also possible that each version of Falcon 9 has its own blocks (revisions). The only boosters recovered so far were all FT. Musk was mentioning that there is no point of reflying block 3 or 4 too many times, they wait for block 5, which points to them being versions of FT. We won't know unless SpaceX people officially confirm this.

Spiice said they haven't flown all the Block 3's yet, and Musk said they haven't started producing Block 5 but will start in a few months. Since 1.0 is apparently Block 1 per the old User Guide, that gives:

Block 1 = v1.0
Block 2 = v1.1
Block 3 = v1.2/Full Thrust, currently flying
Block 4 = Fuller thrust, FT upgrade currently in production, will fly late 2016/early 2017
Block 5 = Upcoming FT upgrade in production early 2017, will fly mid/late 2017.

Makes sense to me.
Title: Re: Falcon 9 (Future) speculation
Post by: tleski on 10/26/2016 05:56 pm

Spiice said they haven't flown all the Block 3's yet, and Musk said they haven't started producing Block 5 but will start in a few months. Since 1.0 is apparently Block 1 per the old User Guide, that gives:

Block 1 = v1.0
Block 2 = v1.1
Block 3 = v1.2/Full Thrust, currently flying
Block 4 = Fuller thrust, FT upgrade currently in production, will fly late 2016/early 2017
Block 5 = Upcoming FT upgrade in production early 2017, will fly mid/late 2017.

Makes sense to me.

Yes, so it looks like hkultala's option b. That sounds most likely based on all we've heard so far.
Title: Re: Falcon 9 (Future) speculation
Post by: enbandi on 10/27/2016 06:24 pm
Hi!

I agree with the option b, (Block 3 = v1.2/FT theory), but Block 2 makes some confusion: it was originally introduced as a v1.0 variant (Falcon 9 Rev 1 User Guide) (http://www.spaceflightnow.com/falcon9/001/f9guide.pdf), and  Space Launch Report Falcon 9 1.0 datasheet (http://www.spacelaunchreport.com/falcon9.html)

And another clue (maintains option b;): Elon said in the AMA, that  "there isn't much point in ground testing Block 3 or 4 much beyond a few reflights" (https://www.reddit.com/r/spacex/comments/590wi9/i_am_elon_musk_ask_me_anything_about_becoming_a/d94v8p8/), while they got F9-023 (flown in CRS-8) as the oldest core available for testing. This implicate that the 023 should be Block 3...

Title: Re: Falcon 9 (Future) speculation
Post by: DJPledger on 10/27/2016 07:55 pm
I think Falcon 9 Block 5 will fly for a few years before it is replaced by an all new single core Raptor powered LV which will also replace FH.
Title: Re: Falcon 9 (Future) speculation
Post by: guckyfan on 10/27/2016 09:24 pm
I think Falcon 9 Block 5 will fly for a few years before it is replaced by an all new single core Raptor powered LV which will also replace FH.

If that happens, the new launch vehicle will have the same arrangement of 7 Raptor as on the center of the BFR. They can directly use the plumbing design and I always liked the idea of 7 equidistant engines.
Title: Re: Falcon 9 (Future) speculation
Post by: envy887 on 10/28/2016 03:19 pm
I think Falcon 9 Block 5 will fly for a few years before it is replaced by an all new single core Raptor powered LV which will also replace FH.

If that happens, the new launch vehicle will have the same arrangement of 7 Raptor as on the center of the BFR. They can directly use the plumbing design and I always liked the idea of 7 equidistant engines.

I don't think SpaceX is going to develop ITS and then work on a smaller LV, or take resources off ITS to concurrently develop a smaller LV. If they really are finishing all Falcon/Dragon dev work next year to focus only on ITS (and Musk's presentation is pretty clearly says that's his plan), then the "all new single core Raptor powered LV which will also replace FH" is ITS. If they wanted an intermediate size LV it makes WAY more sense to build it before ITS.

If the ITS plans hit a major roadblock, then I'd guess the alternative is a 6 meter class reuseable upper stage, initially launched by FH and eventually by a New Glenn-size methalox single stick. That still gives about a 50 tonne payload to Mars.
Title: Re: Falcon 9 (Future) speculation
Post by: JasonAW3 on 10/28/2016 04:33 pm
I think Falcon 9 Block 5 will fly for a few years before it is replaced by an all new single core Raptor powered LV which will also replace FH.

If that happens, the new launch vehicle will have the same arrangement of 7 Raptor as on the center of the BFR. They can directly use the plumbing design and I always liked the idea of 7 equidistant engines.

I don't think SpaceX is going to develop ITS and then work on a smaller LV, or take resources off ITS to concurrently develop a smaller LV. If they really are finishing all Falcon/Dragon dev work next year to focus only on ITS (and Musk's presentation is pretty clearly says that's his plan), then the "all new single core Raptor powered LV which will also replace FH" is ITS. If they wanted an intermediate size LV it makes WAY more sense to build it before ITS.

If the ITS plans hit a major roadblock, then I'd guess the alternative is a 6 meter class reuseable upper stage, initially launched by FH and eventually by a New Glenn-size methalox single stick. That still gives about a 50 tonne payload to Mars.

At a guess, I'd suspect that they would develop and build the ITS while progressively refining the Falcon 9.

      I wouldn't be surprised if they create a carbon fiber based version, primarily to refine the use of a fully composite ITS bird.
Title: Re: Falcon 9 (Future) speculation
Post by: envy887 on 10/28/2016 06:57 pm
At a guess, I'd suspect that they would develop and build the ITS while progressively refining the Falcon 9. I wouldn't be surprised if they create a carbon fiber based version, primarily to refine the use of a fully composite ITS bird.
A composite F9 is not a "progressive refinement", it's a completely new airframe with major changes to facilities and processes required for manufacturing, testing, and qualification. It's almost as much work as a clean-sheet design with few of the advantages of a real clean-sheet design.
Title: Re: Falcon 9 (Future) speculation
Post by: JMS on 10/28/2016 09:17 pm
Any speculation on "improved legs"?
Title: Re: Falcon 9 (Future) speculation
Post by: douglas100 on 10/30/2016 08:43 am
Legs which can be conveniently retracted after landing?
Title: Re: Falcon 9 (Future) speculation
Post by: deruch on 11/02/2016 12:38 am
Any speculation on "improved legs"?
Legs which can be conveniently retracted after landing?
And/Or ones that allow for the fabled early-deployment/aerobraking?
Title: Re: Falcon 9 (Future) speculation
Post by: John Alan on 11/02/2016 03:49 pm
Any speculation on "improved legs"?
Legs which can be conveniently retracted after landing?
And/Or ones that allow for the fabled early-deployment/aerobraking?

Nah...  ;)
Falcon 9 leg improvement/development...
They will pilot the stubby fins and RCS assisted landing idea onto a landing cradle added to OCISLY or JRTI...
 :o  ::)  8)

Speculation...   ;)
Title: Re: Falcon 9 (Future) speculation
Post by: cambrianera on 11/02/2016 07:33 pm
Legs which can be conveniently retracted after landing?
Or after lift-off.
SpaceX has already them for ITS.
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/02/2016 08:09 pm

They will pilot the stubby fins and RCS assisted landing idea onto a landing cradle added to OCISLY or JRTI...


A useless operation.   If they are going to land on a barge, there is no reason to eliminate the legs.
Title: Re: Falcon 9 (Future) speculation
Post by: IainMcClatchie on 11/02/2016 09:28 pm
If you eliminate the legs, you eliminate the fuel to move them.  The legs are ~10% of the landed mass of the first stage, and so you can reduce the fuelled mass by 10% as well.  That's 2-3 tonnes of fuel.

Getting rid of the legs on the upper stage is vastly more helpful, especially if the upper stage is required to land a significant amount of payload (e.g. more than it's own dry mass).  The landing gear could end up weighing more than the propellant tanks!  I didn't see anything in Elon's presentation on that, but I would assume the tanker has no landing gear.

Eliminating the landing gear on the Mars lander could be helpful, as it pushes through a very large delta-V and it's required to land a large payload.  Also, if the Mars lander has no landing gear, then none of the vehicles have landing gear and there is no need for the R&D, but maybe that's a small thing.

I have not come up with a scheme to build a active capture cradle on Mars, without first having an ITS with landing gear.  You could have two versions, but that seems ridiculous if there is only a small gain.

Maybe the first (big) thing that lands on Mars is a special spaceship that converts itself into a launch and recovery pad.  It's engines and maybe other flight hardware are perhaps removed and kept as spares for later vehicles.
Title: Re: Falcon 9 (Future) speculation
Post by: Lars-J on 11/02/2016 10:35 pm
Getting rid of the legs on the upper stage is vastly more helpful, especially if the upper stage is required to land a significant amount of payload (e.g. more than it's own dry mass).  The landing gear could end up weighing more than the propellant tanks!  I didn't see anything in Elon's presentation on that, but I would assume the tanker has no landing gear.

The tanker has a landing gear. Watch the video again, it starts out sitting on its gear before being lifted on top of the stack. Commonality with the ship matters a whole lot to make it affordable.

Eliminating the landing gear on the Mars lander could be helpful, as it pushes through a very large delta-V and it's required to land a large payload.  Also, if the Mars lander has no landing gear, then none of the vehicles have landing gear and there is no need for the R&D, but maybe that's a small thing.

Any Mars lander will have a landing gear. It is necessary. What you are speculating might be viable in a distant future that has more Mars infrastructure, but it sure isn't what SpaceX is proposing.
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/02/2016 11:09 pm
If you eliminate the legs,


Which is nonsense.  Helicopters still have landing gear
Title: Re: Falcon 9 (Future) speculation
Post by: tdperk on 11/02/2016 11:51 pm
Which is nonsense.  Helicopters still have landing gear

What nonsense, helicopters need to land anywhere.

A rocket which can land on it's launch pad only needs to land on that pad.
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/03/2016 12:02 am

1.  What nonsense, helicopters need to land anywhere.

2.  A rocket which can land on it's launch pad only needs to land on that pad.

1.  So does the lander, anywhere on Mars

2.  Not a proven concept
Title: Re: Falcon 9 (Future) speculation
Post by: JasonAW3 on 11/03/2016 05:55 pm
At a guess, I'd suspect that they would develop and build the ITS while progressively refining the Falcon 9. I wouldn't be surprised if they create a carbon fiber based version, primarily to refine the use of a fully composite ITS bird.
A composite F9 is not a "progressive refinement", it's a completely new airframe with major changes to facilities and processes required for manufacturing, testing, and qualification. It's almost as much work as a clean-sheet design with few of the advantages of a real clean-sheet design.

Ok, But could the scaled down Raptor Test engine be adapted to work on a Falcon 9 converted to work with Methalox?

      This could give them some real world experience with both fuel handling and recovery of such a beast.  Plus you have a better ISP no coking issues and in general overall better performance without the need for Helium tanks.  While the performance boost may not seem significant enough to justify such a conversion, the overall mass differences between the Sub-scale Raptor engines versus the Merlins should either balance out, or actually lower the overall mass of the entire stack.

      I'm not sure if THIS would require a clean sheet redesign, or more of a retooling and conversion of what they already have.
Title: Re: Falcon 9 (Future) speculation
Post by: JasonAW3 on 11/03/2016 06:32 pm

1.  What nonsense, helicopters need to land anywhere.

2.  A rocket which can land on it's launch pad only needs to land on that pad.

1.  So does the lander, anywhere on Mars

2.  Not a proven concept

I'm kinda with Jim on this one.

      I would much rather have a booster that could land on legs, if need be, than to have a booster that would topple and be destroyed if it were a couple of meters off on its landing.

      Landing the booster at the pad is great in concept, but in practice, the risk to not only the booster itself, but the launch tower, and other facilities makes me cringe.

     Personally, I'd prefer the current stacking technique that SpaceX uses for the Falcon 9.  Assemble the stack on its side, truck it out to the pad, erect it and launch.  (After fueling, prep. etc.)

     Landing the ITS booster on a concrete landing pad near a SpaceX Horizontal Assembly Building, (HAB) using the same erector gantry that would be used to erect it to return it to the SpaceX HAB, makes a LOT more sense, and, in the long term, likely be cheaper, overall, than landing at the pad and doing a vertical assembly, without the support of a VAB.

     The Mobile Erector Gantry, (MEG) would likely required some detachable counterweights to assist the hydraulics on elevating the whole stack, but it should be possible, as many comparably sized drawbridges, of similar mass to this whole rig, use much the same system, (minus the detachable counterweights) for major roads and highways.

      While I DO agree simple is better in most cases, the risks involved are WAY to big (as would replacement costs be) to do a launch pad landing right off the bat.  Maybe after a few flights where they can prove the accuracy of the landings, but not right away.

      Besides, aircraft have a fairly large landing strip that they use, and can usually wave off if conditions aren't right for landing, and even with these advantages, they sometimes crash or slide off the runway.  The ITS booster would have NONE of these advantages.  All it would take would be a sudden, powerful gust of wind in the wrong place at the wrong time, and BOOM.  at least 2 years rebuilding and a few hundred million dollars in lost equipment.  On an open concrete pad, there is FAR less likelihood of disaster, and the environment would be MUCH more fault tolerant.

     While I ranted on about the ITS, the Falcon 9 would be even LESS fault tolerant, returning to its pad!
Title: Re: Falcon 9 (Future) speculation
Post by: GreenShrike on 11/03/2016 07:33 pm
Ok, But could the scaled down Raptor Test engine be adapted to work on a Falcon 9 converted to work with Methalox?

Of course, if you're willing to foot the bill.

But would such an upgrade pay for itself? I don't see a methalox booster providing cost reduction or capability increases over the kerolox F9, and it kind of needs to, since with a Martian colony to pay for, SpaceX doesn't really have money to splash about for nothing more than grins.

      This could give them some real world experience with both fuel handling and recovery of such a beast.  Plus you have a better ISP no coking issues and in general overall better performance without the need for Helium tanks.  While the performance boost may not seem significant enough to justify such a conversion, the overall mass differences between the Sub-scale Raptor engines versus the Merlins should either balance out, or actually lower the overall mass of the entire stack.

ISP and mass make little difference on boosters. And F9 doesn't really need a few more percentage points worth of performance, since it can fly a lot of things and FH is a relatively inexpensive upgrade to fly the rest. Ultimately, F9 can do its job, and hasn't had nearly enough of a run to have fully earned its keep just to be flushed down the toilet and replaced with something with little or no additional capability.

Raptor *could* make a difference, though, if SpaceX were to target Falcon's Achilles heel -- the upper stage.

You get your laundry list of benefits -- better ISP, little-to-no coking, experience in fuel handling, no helium -- while also adding experience with a fully cryogenic composite in-space rocket stage, recovery of an in-space stage, potential ACES-like operation including distributed launch (which would test BFS refueling ops), and a big kick in the pants for performance. Maybe even those gaseous methalox thrusters for RCS and landing.

The performance, of course, would probably all get eaten up by recovery hardware and operations, but that would be okay if they can reuse the stage and thus lower launch costs. So they'd get testing *and* new capabilities *and* potentially lower costs.

If SpaceX were to sink money into switching some part of Falcon to methalox, I'm thinking they'd get a much better return if it was the upper stage.
Title: Re: Falcon 9 (Future) speculation
Post by: meekGee on 11/04/2016 02:05 am
SoaceX has yet to have a single good landing that was off-center.  So doubting the value of land-anywhere for the tanker is reasonable.

Basically, the scenario where you can't get to center pad, but still have a healthy vehicle enough fuel, and a good surface to land on, may be exceedingly rare.

Remember that before the ITS video, the entire concept of a cradle was ridiculed here.

Title: Re: Falcon 9 (Future) speculation
Post by: Raul on 11/04/2016 07:33 am
Ok, But could the scaled down Raptor Test engine be adapted to work on a Falcon 9 converted to work with Methalox?
Of course, if you're willing to foot the bill.

I think Air Force shares cost investment with SpaceX for the development of a prototype of the Raptor engine for the upper stage of the Falcon 9 and Falcon Heavy launch vehicles.
http://www.defense.gov/News/Contracts/Contract-View/Article/642983
Quote
This other transaction agreement requires shared cost investment with SpaceX for the development of a prototype of the Raptor engine for the upper stage of the Falcon 9 and Falcon Heavy launch vehicles. The locations of performance are NASA Stennis Space Center, Mississippi; Hawthorne, California; and Los Angeles Air Force Base, California. The work is expected to be completed no later than Dec. 31, 2018. Air Force fiscal 2015 research, development, test and evaluation funds in the amount of $33,660,254 are being obligated at the time of award.  SpaceX is contributing $67,320,506 at the time of award.
Title: Re: Falcon 9 (Future) speculation
Post by: RonM on 11/04/2016 01:36 pm
Remember that before the ITS video, the entire concept of a cradle was ridiculed here.

While landing in a cradle can work, land in a cradle at the launch pad should be ridiculed. Just one accident in the middle of all the launch pad infrastructure can knock the pad out of operation for over a year.

Land in a cradle nearby, but not too close, and then transport the vehicle to the pad. With a little creative engineering, moving the booster back to the pad can be done quickly.

IMHO, I don't think modifying F9 for cradle landing is worth the effort. A custom F9 for testing sure, but not the production model.
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/04/2016 01:39 pm

Remember that before the ITS video, the entire concept of a cradle was ridiculed here.



Still is

SoaceX has yet to have a single good landing that was off-center.  So doubting the value of land-anywhere for the tanker is reasonable.



Because an off center landing is a bad landing and they have had those
Title: Re: Falcon 9 (Future) speculation
Post by: JasonAW3 on 11/04/2016 02:02 pm
Ok, But could the scaled down Raptor Test engine be adapted to work on a Falcon 9 converted to work with Methalox?

Of course, if you're willing to foot the bill.

But would such an upgrade pay for itself? I don't see a methalox booster providing cost reduction or capability increases over the kerolox F9, and it kind of needs to, since with a Martian colony to pay for, SpaceX doesn't really have money to splash about for nothing more than grins.

    Well, ONE advantage would be a reduced amount of complexity in fueling and another major advantage is the elimination of any Helium COPV issues in the future.  The helium tank issues have cost two vehicles and a few hundred million in payloads.

      At this point, it MIGHT be an idea to investigate some possible alternatives.  The way I see it, they've already got most of the tooling in place to make these sub-scale engines, and conversion of the actual stage hardware would actually reduce the complexity of the system.
Title: Re: Falcon 9 (Future) speculation
Post by: Robotbeat on 11/04/2016 02:34 pm
They don't have tooling for subscale engines. They have tooling for high pressure engines that they can run at lower pressures for initial testing.
Title: Re: Falcon 9 (Future) speculation
Post by: Jet Black on 11/04/2016 03:20 pm
     Landing the ITS booster on a concrete landing pad near a SpaceX Horizontal Assembly Building, (HAB) using the same erector gantry that would be used to erect it to return it to the SpaceX HAB, makes a LOT more sense, and, in the long term, likely be cheaper, overall, than landing at the pad and doing a vertical assembly, without the support of a VAB.

     The Mobile Erector Gantry, (MEG) would likely required some detachable counterweights to assist the hydraulics on elevating the whole stack, but it should be possible, as many comparably sized drawbridges, of similar mass to this whole rig, use much the same system, (minus the detachable counterweights) for major roads and highways.


Another possibility is picking it up vertically. The carrier does not have to be as tall as the rocket since it only needs to have connection points above the center of gravity, and some connections below for stability. In either case, landing at the pad seems crazy to me.
Title: Re: Falcon 9 (Future) speculation
Post by: douglas100 on 11/04/2016 03:42 pm
Just to comment about my last post. I was specifically talking about improvements to the F9 landing gear. Yet somehow the conversation has morphed into a discussion about ITS. That's fine, but I suggest this isn't the thread for it.
Title: Re: Falcon 9 (Future) speculation
Post by: matthewkantar on 11/04/2016 03:48 pm
2.  Not a proven concept

If we stuck to proven concepts we would still be living in caves.

Matthew
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/04/2016 04:29 pm
2.  Not a proven concept

If we stuck to proven concepts we would still be living in caves.


That isn't the point.  The point is that intermediate steps can't be assumed.
Title: Re: Falcon 9 (Future) speculation
Post by: woods170 on 11/04/2016 04:36 pm

Remember that before the ITS video, the entire concept of a cradle was ridiculed here.



Still is

SoaceX has yet to have a single good landing that was off-center.  So doubting the value of land-anywhere for the tanker is reasonable.



Because an off center landing is a bad landing and they have had those
Off center landing does not equate to one where the booster fell over and did a RUD. There was at least one off center landing that resulted in the booster making it safe to port.
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/04/2016 04:45 pm

Remember that before the ITS video, the entire concept of a cradle was ridiculed here.



Still is

SoaceX has yet to have a single good landing that was off-center.  So doubting the value of land-anywhere for the tanker is reasonable.



Because an off center landing is a bad landing and they have had those
Off center landing does not equate to one where the booster fell over and did a RUD. There was at least one off center landing that resulted in the booster making it safe to port.

That does no good for cradle
Title: Re: Falcon 9 (Future) speculation
Post by: meekGee on 11/04/2016 05:48 pm
Remember that before the ITS video, the entire concept of a cradle was ridiculed here.

While landing in a cradle can work, land in a cradle at the launch pad should be ridiculed. Just one accident in the middle of all the launch pad infrastructure can knock the pad out of operation for over a year.

Land in a cradle nearby, but not too close, and then transport the vehicle to the pad. With a little creative engineering, moving the booster back to the pad can be done quickly.

IMHO, I don't think modifying F9 for cradle landing is worth the effort. A custom F9 for testing sure, but not the production model.

An off-pad cradle is where I went first too, but I'm still on the fence on that one.  It really depends on how many launch pads they plan to have.

They're talking about REALLY high-rate reusability.  I'm sure they considered an off-pad cradle (doesn't exactly take a genius to think about it) and my guess is that the added complexity and handling was not worth it - it slows you down during nominal operations.

Might as well build another pad instead.  More expensive, but it allows you 2x the tempo during nominal operations.



Title: Re: Falcon 9 (Future) speculation
Post by: JamesH65 on 11/04/2016 06:56 pm
SpaceX, the company leading the world in landing boosters, after years of investigation and experience think the ITS can land in a cradle.

Their opinion is ridiculed by many people who haven't even launched a booster, never mind landed one.

I wonder who's opinion Occam's razor would  veer towards.

Of course, time will tell whether they are right. I hope they are.
Title: Re: Falcon 9 (Future) speculation
Post by: Robotbeat on 11/04/2016 07:38 pm
Mastem Space Systems is also pursuing launch cradle. They thought of it before SpaceX, I think. Masten also inspired SpaceX to pursue booster landing in the first place. Masten has more experience (by # of flights) doing VTVL rocket landings than, I think, everyone else in the world combined. Hundreds of flights (as defined by FAA).
Title: Re: Falcon 9 (Future) speculation
Post by: Earendil on 11/05/2016 08:39 am
IMHO, I do not think landing cradle will happen to F9, regardless of its iteration (excluding wacky F9 raptor theories.. that won't be F9 at all).

Why it is OK for ITS booster, but not for F9?
T/W of course..

With one engine, BFR will be able to hover and fine tune it's landing spot..

F9 will always hover-slam .. as good as they are with their landings, there is just not enough time to adjust at the last seconds..   How far off center can they land successfully on a cradle.. 0.5m? 1m?  Even if they do it bulls eye 49 out of 50 times.. one mistake is enough to ruin the whole complex. Might be sudden gusts of wind, might be a tiny bit off actuator or engine thrust.. things which can be compensated at the last moment by BFR, but not buy F9.

Title: Re: Falcon 9 (Future) speculation
Post by: MATTBLAK on 11/05/2016 10:14 am
Final thrust upgrades for the Merlin 1D series (Merlin 1E?). Another propellant tank stretch for the second stage? Modifications to the second stage to allow even longer life for missions with multiple engine restarts? New family of payload fairings - reuse and wider/longer fairings?
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/05/2016 10:16 am
SpaceX, the company leading the world in landing boosters, after years of investigation and experience think the ITS can land in a cradle.


The issue is not cradle but launch pad
Title: Re: Falcon 9 (Future) speculation
Post by: Dante80 on 11/05/2016 10:41 am
Reminder, we are still talking about the Falcon9 here. You do know that NASA will not (and should not) put astronauts into a rolling design, and that SpaceX will have to design lock block 5 before CC is live. I mean, NASA - unsurprisingly - has not even got over the change to densified propellants yet, and here we are talking about miniature raptors etc etc...

Some of the speculation here, especially regarding big changes is very unrealistic imo. What SpaceX has to do is to inform the design with lessons taken from re-usability, and then LOCK/FREEZE it. They don't have much time for that either, as they have said themselves a lot of times they have to change this project from R&D to stable production mode asap.
Title: Re: Falcon 9 (Future) speculation
Post by: rsdavis9 on 11/05/2016 10:53 am
Yes. Lock down design.
They have to take innovation and experimentation to the next vehicle.
Elon has already said as much.
Next year engineers will be working on ITS.
Title: Re: Falcon 9 (Future) speculation
Post by: docmordrid on 11/06/2016 04:05 pm
Final thrust upgrades for the Merlin 1D series (Merlin 1E?). Another propellant tank stretch for the second stage? Modifications to the second stage to allow even longer life for missions with multiple engine restarts? New family of payload fairings - reuse and wider/longer fairings?

If the new Merlin performance is from removing software limits why rename it?

For longer life mods - maybe a conformal array akin to Dragon 2's trunk, a larger battery and a small RP-1 tank heater/stirrer to prevent gelling?

A longer fairing seems necessary. Long March 5 will have a 20.5m fairing, Atlas V and Vulcan nearly that (19?), so if they plan to launch the largest payloads on FH they'll need it anyhow. It would also allow B330 module launches.

Doubt the S2 tank stretch. Its pretty fine already and a longer fairing plus the tank....
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/06/2016 04:33 pm

A longer fairing seems necessary. ...

Spacex doesn't think so
Title: Re: Falcon 9 (Future) speculation
Post by: tdperk on 11/07/2016 01:00 pm
You do know that NASA will not (and should not) put astronauts into a rolling design

NASA has already proudly put astronauts into a prematurely "locked" design and accepted loss of crew 1 launch out of 50.

This was on a vehicle with no LES.

Both those losses were for inane reasons, bordering on criminal negligence in my view, reasons that on a "not locked" design would have been fixed incrementally in the course of vehicle engineering evolution--one thereby becoming continually more safe and capable.

Why do I say more safe and more capable?  Because if you fix what you know can be improved, trust that replicable launch procedures will reveal with cargo only launches if there are unknown interactions with fixes, and only launch crew on a build version hat has a few launches under it's belt...

...Then you aren't accepting the normalization of deviance, with it's concomitant complacency, which the other approach seems to inculcate unavoidably.
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/07/2016 01:04 pm
You do know that NASA will not (and should not) put astronauts into a rolling design

NASA has already proudly put astronauts into a prematurely "locked" design and accepted loss of crew 1 launch out of 50.


That was in the past and not applicable to this discussion
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/07/2016 01:05 pm
reasons that on a "not locked" design would have been fixed incrementally in the course of vehicle engineering evolution--one thereby becoming continually more safe and capable.


And that is a description of what was done with the shuttle
Title: Re: Falcon 9 (Future) speculation
Post by: tdperk on 11/07/2016 02:15 pm
NASA has already proudly put astronauts into a prematurely "locked" design and accepted loss of crew 1 launch out of 50.

That was in the past and not applicable to this discussion

That's one opinion.

Quote
And that is a description of what was done with the shuttle

Not so an interested observer could tell.

What is evident is the normalization of deviance, as the phrase goes.
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/07/2016 02:38 pm

That's one opinion.

It is a fact.  It is in the past.  And a different regime exists.

By your same logic, Spacex is going to keep blowing up second stages.


Not so an interested observer could tell.


Wrong, that "observer" would have to be extremely biased not to be able to tell or not in command of all his senses.


What is evident is the normalization of deviance, as the phrase goes.

Like Spacex and helium issues?
Title: Re: Falcon 9 (Future) speculation
Post by: woods170 on 11/07/2016 05:29 pm

That's one opinion.

It is a fact.  It is in the past.  And a different regime exists.

By your same logic, Spacex is going to keep blowing up second stages.


Not so an interested observer could tell.


Wrong, that "observer" would have to be extremely biased not to be able to tell or not in command of all his senses.


What is evident is the normalization of deviance, as the phrase goes.

Like Spacex and helium issues?
Yes, very much like NASA and ET foam release.
Title: Re: Falcon 9 (Future) speculation
Post by: Dante80 on 11/08/2016 05:29 am
Quote
NASA has already proudly put astronauts into a prematurely "locked" design and accepted loss of crew 1 launch out of 50.

The fact that NASA has done something bad or risky in the past does not mean they will continue doing it in the future, or that you should expect/want them to. The CC program has different requirements, pre-requisites and standards than past manned programs.

If SpaceX cannot make the grade...then there is always Boeing. If both cannot, well that would mean that NASA should not have even funded them in the first place, or allowed them the leeway or lack of insight it did concerning many aspects of the program (as opposed to another more conservative program type).
Title: Re: Falcon 9 (Future) speculation
Post by: Robotbeat on 11/08/2016 05:31 am
Is going into space worth risking life over?
Title: Re: Falcon 9 (Future) speculation
Post by: Dante80 on 11/08/2016 05:38 am
Is going into space worth risking life over?

To routinely ferry government employees to and from the ISS? Definetely not.
Title: Re: Falcon 9 (Future) speculation
Post by: Robotbeat on 11/08/2016 05:42 am
Is going into space worth risking life over?

To routinely ferry government employees to and from the ISS? Definetely not.
Okay, we should abandon it right now then. Space is risky.
Title: Re: Falcon 9 (Future) speculation
Post by: Dante80 on 11/08/2016 05:44 am
Is going into space worth risking life over?

To routinely ferry government employees to and from the ISS? Definetely not.
Okay, we should abandon it right now then. Space is risky.

No, that is not how it goes. You are pursuing a red herring here. Space is always risky. That does not mean though that you a priori accept risk that you can mitigate while keeping the goal at hand.

The CC program has certain standards concerning safety risk mitigation. Those standards are set by the customer that pays, and the contractors that will provide the service must make the grade and attain them. If they cannot, you cannot blame the customer here.

To bring the discussion back to the topic, what I said is that SpaceX themselves have aknowledged the need to "feature lock" the F9 design on block 5, and move from R&D to production mode by the end of the next year, both to send resources over to ITS and reach a stable state on the F9 project, focusing on launch cadence thereafter. This automatically means that some of the most ambitious proposals from our fellow forumites in this thread are unrealistic.

An additional reason that SpaceX wants to do this is because CC "requires" it. NASA paid for Dragon 2 integration to a proven LV, not a rolling LV experiment on top of it.
Title: Re: Falcon 9 (Future) speculation
Post by: envy887 on 11/08/2016 12:41 pm
I don't understand the assessment that fueling with the crew aboard has a higher probability of loss of life than having them board afterward.

The probability of a catastrophic failure during fueling would have to be higher than the probability of failure after fueling but before launch by roughly a factor of the reliability of the escape system.

E.g. if there is a 1% chance of a catastrophic event after fueling but before the LAS is armed and the ground crew removed to a safe distance, that's equivalent to a 10% chance of failure during fueling with a 90% reliable armed LAS. Either way, there's a ~1% chance of killing the flight crew... but in the former scenario the accident kills the ground crew as well.

I understand that you don't WANT to use the LAS, but I haven't seen any evidence suggesting that relying on the LAS is more likely to cause deaths than approaching a fueled LV.
Title: Re: Falcon 9 (Future) speculation
Post by: jak Kennedy on 11/08/2016 01:24 pm
And are they not constantly topping off after the crew is on board in the case where the rocket is fueled first?
Title: Re: Falcon 9 (Future) speculation
Post by: smfarmer11 on 11/08/2016 01:58 pm
Yes, they are. They have to constantly top off due to LOX boiloff.
Title: Re: Falcon 9 (Future) speculation
Post by: John Alan on 11/08/2016 02:13 pm
Yes, they are. They have to constantly top off due to LOX boiloff.

With subcooled LOX... there is very little boiloff going on... not like the nomal way...

As to the subject at the moment... crew on, then load...
Envy887 hit the nail on the head... It's safer in my opinion...
Rocket powered on and shows good BUT no Fuel or Lox loaded...
Strap the crew in and arm the LAS... clear the pad..
Fill it up and then go when ready...

My opinion is NASA will approve this method in the end...  ;)
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/08/2016 02:15 pm

Envy887 hit the nail on the head... It's safer in my opinion...

And you both are wrong.  And AMOS-6 demonstrates why.  Regardless of what Musk said, he has to prove that the LAS would work.    Also, it means the crew can't move or look around.  They have to be in a state to be ready for the LAS to go off at any second.
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/08/2016 02:20 pm

I understand that you don't WANT to use the LAS, but I haven't seen any evidence suggesting that relying on the LAS is more likely to cause deaths than approaching a fueled LV.

There are many.  Failed thruster, failed guidance, damage from booster, failure to separate, chute failure, etc
Title: Re: Falcon 9 (Future) speculation
Post by: Silmfeanor on 11/08/2016 02:47 pm

I understand that you don't WANT to use the LAS, but I haven't seen any evidence suggesting that relying on the LAS is more likely to cause deaths than approaching a fueled LV.

There are many.  Failed thruster, failed guidance, damage from booster, failure to separate, chute failure, etc

What side do you think it will go to Jim? Will SpaceX have to bite the bullet, change procedures (even if that requires a substantial redesign-possibly even letting go of subcooled prop) or will NASA come to the conclusion that the % failure due to malfunctioning LAS is acceptable?
Or is there too little information to make a judgement?
Title: Re: Falcon 9 (Future) speculation
Post by: envy887 on 11/08/2016 03:11 pm

I understand that you don't WANT to use the LAS, but I haven't seen any evidence suggesting that relying on the LAS is more likely to cause deaths than approaching a fueled LV.

There are many.  Failed thruster, failed guidance, damage from booster, failure to separate, chute failure, etc

Sure, there are plenty of possible failure modes in launch abort. Those aren't evidence that it's riskier than standing next to a fueled LV. Without a full risk analysis of all possible failure modes and associated probabilities and hazards, I can't see how it's possible to make a judgement one way or the other.
Title: Re: Falcon 9 (Future) speculation
Post by: RotoSequence on 11/08/2016 03:16 pm

I understand that you don't WANT to use the LAS, but I haven't seen any evidence suggesting that relying on the LAS is more likely to cause deaths than approaching a fueled LV.

There are many.  Failed thruster, failed guidance, damage from booster, failure to separate, chute failure, etc

What side do you think it will go to Jim? Will SpaceX have to bite the bullet, change procedures (even if that requires a substantial redesign-possibly even letting go of subcooled prop) or will NASA come to the conclusion that the % failure due to malfunctioning LAS is acceptable?
Or is there too little information to make a judgement?

In my couple of years here, Jim's general approach has been to reality check overly risky, overly optimistic, and generally unrealistic speculation. I don't think he likes offering his own speculative outlook, unless it involves a decision that he knows about, that has been made by someone with the authority to make it.
Title: Re: Falcon 9 (Future) speculation
Post by: envy887 on 11/08/2016 03:29 pm

Envy887 hit the nail on the head... It's safer in my opinion...

And you both are wrong.  And AMOS-6 demonstrates why.  Regardless of what Musk said, he has to prove that the LAS would work.    Also, it means the crew can't move or look around.  They have to be in a state to be ready for the LAS to go off at any second.

AMOS-6 demonstrates nothing except that energized LVs are dangerous. A similar anomaly could potentially happen anytime after fueling starts, including while crew are in the process of boarding an energized vehicle.

It's certainly possible (even probable, IMO) that SpaceX's fueling processes themselves are inherently more dangerous than other LVs. I certainly wouldn't want to be around while they're fueling a Falcon. But I definitely wouldn't walk up to one after it's fueled either. But in this case the fueling process itself should be critically evaluated.
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/08/2016 03:44 pm

AMOS-6 demonstrates nothing except that energized LVs are dangerous. A similar anomaly could potentially happen anytime after fueling starts, including while crew are in the process of boarding an energized vehicle.


No, the vehicle is in a steady state before the crew boards and hence such a anomaly doesn't happen.  Anomalies happen during fueling and not after in steady state.  In the past, there are cases where serious anomalies* have happened, where a crew would not have boarded and the launch scrubbed.  There haven't been cases where the vehicle is steady state and serious anomalies have occurred before T-0.

And there are other instances that supports my case.  AMOS-6 is not the first time Spacex has had a serious problem during prop load.  And at that time, the crew would have been in danger and the likely outcome would have been the LAS and a destroyed rocket and pad.  But in the end, luck was on Spacex side and the vehicle was able to fly.



*unmanned mission
Title: Re: Falcon 9 (Future) speculation
Post by: old_sellsword on 11/08/2016 03:59 pm
There haven't been cases where the vehicle is steady state and serious anomalies have occurred before T-0.

What about Soyuz T-10-1 (https://en.wikipedia.org/wiki/Soyuz_7K-ST_No._16L)? It caught fire between fueling completion and launch (T-90 seconds).
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/08/2016 04:18 pm
There haven't been cases where the vehicle is steady state and serious anomalies have occurred before T-0.

What about Soyuz T-10-1 (https://en.wikipedia.org/wiki/Soyuz_7K-ST_No._16L)? It caught fire between fueling completion and launch (T-90 seconds).

US systems
Title: Re: Falcon 9 (Future) speculation
Post by: Proponent on 11/08/2016 06:01 pm
What about the Atlas that collapsed after it lost internal pressure.
Title: Re: Falcon 9 (Future) speculation
Post by: woods170 on 11/08/2016 06:03 pm
There haven't been cases where the vehicle is steady state and serious anomalies have occurred before T-0.

What about Soyuz T-10-1 (https://en.wikipedia.org/wiki/Soyuz_7K-ST_No._16L)? It caught fire between fueling completion and launch (T-90 seconds).

US systems
As in Upper Stage?
Title: Re: Falcon 9 (Future) speculation
Post by: old_sellsword on 11/08/2016 06:05 pm
There haven't been cases where the vehicle is steady state and serious anomalies have occurred before T-0.

What about Soyuz T-10-1 (https://en.wikipedia.org/wiki/Soyuz_7K-ST_No._16L)? It caught fire between fueling completion and launch (T-90 seconds).

US systems
As in Upper Stage?

United States (of America)
Title: Re: Falcon 9 (Future) speculation
Post by: woods170 on 11/08/2016 06:07 pm
There haven't been cases where the vehicle is steady state and serious anomalies have occurred before T-0.

What about Soyuz T-10-1 (https://en.wikipedia.org/wiki/Soyuz_7K-ST_No._16L)? It caught fire between fueling completion and launch (T-90 seconds).

US systems
As in Upper Stage?

United States (of America)
Thank you. But I would like to hear from Jim himself.
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/08/2016 06:35 pm
What about the Atlas that collapsed after it lost internal pressure.

That was during tanking and never got to steady state.  That is another case for crew entry after tanking
Title: Re: Falcon 9 (Future) speculation
Post by: te_atl on 11/08/2016 07:25 pm
There haven't been cases where the vehicle is steady state and serious anomalies have occurred before T-0.

What about Soyuz T-10-1 (https://en.wikipedia.org/wiki/Soyuz_7K-ST_No._16L)? It caught fire between fueling completion and launch (T-90 seconds).

US systems

What are you counting as anomalies?  If the vehicle isn't lost it doesn't count?
You don't count the STS-41D launch abort at T-6 that resulted in a ground level hydrogen fire, or the STS-61C attempt where abort was called at T-31 because LOX was accidentally drained taking it below launch limits?   Does STS-41D not count because the engines fired?   Does STS-61C not count because if the abort had not occurred and it had launched, any premature engine shutdown due to low O2 would have been after launch?
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/08/2016 09:14 pm

What are you counting as anomalies?  If the vehicle isn't lost it doesn't count?
You don't count the STS-41D launch abort at T-6 that resulted in a ground level hydrogen fire, or the STS-61C attempt where abort was called at T-31 because LOX was accidentally drained taking it below launch limits?   Does STS-41D not count because the engines fired?   Does STS-61C not count because if the abort had not occurred and it had launched, any premature engine shutdown due to low O2 would have been after launch?


Don't need to explain why anything after engine start or launch* doesn't count or do I?

*Or even entering terminal count
Title: Re: Falcon 9 (Future) speculation
Post by: envy887 on 11/09/2016 02:01 pm
There haven't been cases where the vehicle is steady state and serious anomalies have occurred before T-0.

It's less likely be certainly possible, especially on a new(ish) LV. There's a lot going on after reaching steady state, including continued tank topping.
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/09/2016 02:51 pm

 There's a lot going on after reaching steady state, including continued tank topping.

Not really.
Title: Re: Falcon 9 (Future) speculation
Post by: jak Kennedy on 11/09/2016 08:50 pm
Yes, they are. They have to constantly top off due to LOX boiloff.

Do you know if they will also top off the LH2 on Atlas while they crew is onboard?
Title: Re: Falcon 9 (Future) speculation
Post by: te_atl on 11/09/2016 09:44 pm

Don't need to explain why anything after engine start or launch* doesn't count or do I?

*Or even entering terminal count

Umm... Actually you do.   Your exact original quote was:

There haven't been cases where the vehicle is steady state and serious anomalies have occurred before T-0.

Both of the cases I cited were where anomalies occurred before T-0.   If you wish to modify your original statement to be "There haven't been cases where the vehicle is steady state and serious anomalies have occurred before engine start.", then I'll retract STS-41D.    But as far as STS-61-C, I know you know this, but for someone that might not, terminal count for the shuttle starts at T-20 minutes, (http://spaceflight.nasa.gov/shuttle/reference/shutref/events/terminal/ (http://spaceflight.nasa.gov/shuttle/reference/shutref/events/terminal/)) with a pre-planned hold at T-9 minutes of usually 10 minutes duration.   So what your saying is that if anything majorly bad had happened in the last 30 minutes sitting on the pad for the shuttle it could never be counted as a serious anomaly?  Sorry... I can't go along with that.

And of course I didn't even list the LO2 temp probe ending up in the pre-valve on the January 9th attempt of that same mission http://forum.nasaspaceflight.com/index.php?topic=2229.msg53407#msg53407 (http://forum.nasaspaceflight.com/index.php?topic=2229.msg53407#msg53407)   The only references I can find is that the probe came off during LO2 fill.   That's most likely outside terminal count, but I haven't found a reference to the timeline where the probe went to fail as mentioned in the above referenced post by Steve_the_Deeve.   So would that count as a serious anomaly?
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/09/2016 11:22 pm

Umm... Actually you do.   Your exact original quote was:


No, I shouldn't have to explain.  But here goes and I will make it simple.   I shouldn't have to explicitly "before engine start" because the crew would be onboard in either case (before or after fueling).  STS-41D gets "retracted" regardless of what you say because of the same thing.   Also it was a "flight" issue or engine problem and something that could not happen before the crew was onboard.  The 61-C temp probe also gets "retracted" because again the crew would be onboard in either case.

And I am not saying that "a majorly bad had happened in the last 30 minutes sitting on the pad for the shuttle it could never be counted as a serious anomaly".   The point is that there have been no serious anomalies that put the crew at risk while sitting at the pad. And that is what this discussion is about and not flight anomalies. 

BTW, terminal count for the shuttle started at T-9 and not T-20.

Title: Re: Falcon 9 (Future) speculation
Post by: envy887 on 11/10/2016 02:00 am
Terminal count risks are unavoidable, as Jim notes, since the flight crew has to be aboard before then.

The Falcon 9 v1.1 countdown avoided most potentially hazardous activities during the time the crew would be boarding and before the LAS would be armed (mostly from 1.5 hours before launch to T-10:00 when terminal count started). The only exception was a LOX top-off at T-30:00.

The current Falcon count moves fuel and LOX tanking into that timeframe immediately before and during terminal count.
Title: Re: Falcon 9 (Future) speculation
Post by: JamesH65 on 11/10/2016 08:09 am

Umm... Actually you do.   Your exact original quote was:


No, I shouldn't have to explain.  But here goes and I will make it simple.   I shouldn't have to explicitly "before engine start" because the crew would be onboard in either case (before or after fueling).  STS-41D gets "retracted" regardless of what you say because of the same thing.   Also it was a "flight" issue or engine problem and something that could not happen before the crew was onboard.  The 61-C temp probe also gets "retracted" because again the crew would be onboard in either case.

And I am not saying that "a majorly bad had happened in the last 30 minutes sitting on the pad for the shuttle it could never be counted as a serious anomaly".   The point is that there have been no serious anomalies that put the crew at risk while sitting at the pad. And that is what this discussion is about and not flight anomalies. 

BTW, terminal count for the shuttle started at T-9 and not T-20.

Yes, you do need to explain - your posts are unfortunately legendary for a lack of explanation, when they really do need it. So thanks for the explanation. Please try to continue in this vein. Not only does it disseminate information, but it means people are more likely to take notice of the content, which in turn means you are less likely to have to repeat yourself. It's a win-win situation.
Title: Re: Falcon 9 (Future) speculation
Post by: te_atl on 11/10/2016 05:48 pm
No, I shouldn't have to explain. 

Before I respond, I want to point out that in general I agree with what I believe you were trying to say.  My problem wasn't with your intent, but that you were too abstract in your statement and read the wrong way it could result in a reader coming up with a false conclusion.   I had two specific problem areas. 

The first is with the timeframe involved.  The second is how you used the term anomaly.

Timeframe: For example, there is a world of difference between stating "no serious anomalies before T-0" and "no serious anomalies before engine start"  41-D, 51F, 68, 55, and 51 all experienced anomalies after main engine start that resulted in RSLS Aborts. http://www.spacesafetymagazine.com/spaceflight/launch/shuttle-launch-pad-aborts (http://www.spacesafetymagazine.com/spaceflight/launch/shuttle-launch-pad-aborts) (51F's RSLS abort is only mentioned in passing in that article).  41-D resulted in that fire, the others had that risk. 

Anomalies: To be clear.  In your original post, you did not differentiate between flight anomalies and non-flight anomalies, you just stated anomalies.  As you pointed out in your last response, there is a difference.  In my original question to you, I specifically asked:

What are you counting as anomalies?

I was trying to get you to expand on your statement by pointing out anomalies that did occur that could have (but thankfully did not) resulted in a really bad day. 

In your last response I have a problem with:
The 61-C temp probe also gets "retracted" because again the crew would be onboard in either case.

If you remove those situations common in both before and after fueling scenarios where the crew is on board, then by definition you remove the whole after fueling scenario, thereby rendering the whole "no serious anomalies" argument moot.


BTW, terminal count for the shuttle started at T-9 and not T-20.

Respectfully, that doesn't agree with the NASA Shuttle Reference Manual site I quoted in my response.   The very first line of that site is "The terminal count phase extends from T minus 20 minutes (T refers to lift-off time) through solid rocket booster ignition."   So in this case we have a discrepancy between reputable sources (you and the NASA site).   

A question then out of curiosity since we do have this discrepancy.  In your opinion/experience, what specific event constitutes the beginning of terminal count that makes terminal count start at T-9 minutes for the shuttle instead of the T-20 minutes from the reference manual?
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/10/2016 06:26 pm

A question then out of curiosity since we do have this discrepancy.  In your opinion/experience, what specific event constitutes the beginning of terminal count that makes terminal count start at T-9 minutes for the shuttle instead of the T-20 minutes from the reference manual?


By definition, a terminal count doesn't have planned holds. 
Title: Re: Falcon 9 (Future) speculation
Post by: tdperk on 11/11/2016 02:36 pm
AMOS-6 is not the first time Spacex has had a serious problem during prop load.

In my opinion if you can fix it with a scrub, tweak, launch the next day, it wasn't a serious problems.

Serious problems are where you need cut new metal.

AMOS-6 is serious problem because of the loss, but there is no reason to think being aware of where the edge of the envelope is and avoiding it is not an entire fix with no new metal cut.
Title: Re: Falcon 9 (Future) speculation
Post by: spacenut on 11/11/2016 02:44 pm
Would it be hard for SpaceX to use only supercooled lox and chilled kerosene on satellite launches and use standard procedures for human launches?  Or can their equipment be adjusted for either?  This might make it safer for LEO human and supply missions to ISS. 
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/11/2016 02:49 pm
AMOS-6 is not the first time Spacex has had a serious problem during prop load.

In my opinion if you can fix it with a scrub, tweak, launch the next day, it wasn't a serious problems.

Serious problems are where you need cut new metal.

AMOS-6 is serious problem because of the loss, but there is no reason to think being aware of where the edge of the envelope is and avoiding it is not an entire fix with no new metal cut.

and those previous problems did require roll back and fixes
Title: Re: Falcon 9 (Future) speculation
Post by: JamesH65 on 11/11/2016 03:53 pm
AMOS-6 is not the first time Spacex has had a serious problem during prop load.

In my opinion if you can fix it with a scrub, tweak, launch the next day, it wasn't a serious problems.

Serious problems are where you need cut new metal.

AMOS-6 is serious problem because of the loss, but there is no reason to think being aware of where the edge of the envelope is and avoiding it is not an entire fix with no new metal cut.

and those previous problems did require roll back and fixes

So, the previous issues have already been fixed. So no longer need to be mentioned/considered?
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/11/2016 03:56 pm

So, the previous issues have already been fixed. So no longer need to be mentioned/considered?

no, it could happen again.  it is always a risk
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/11/2016 03:58 pm

AMOS-6 is serious problem because of the loss, but there is no reason to think being aware of where the edge of the envelope is and avoiding it is not an entire fix with no new metal cut.

Wrong, there may be other unknowns.  And also, what defines the "edge"?
Title: Re: Falcon 9 (Future) speculation
Post by: rabe0070 on 11/11/2016 04:35 pm
Would it be hard for SpaceX to use only supercooled lox and chilled kerosene on satellite launches and use standard procedures for human launches?  Or can their equipment be adjusted for either?  This might make it safer for LEO human and supply missions to ISS.

I also have this question. Due to the fears of many respectable people in aerospace of the fueling procedures, can they easily change them for human rated launches? Is it a design issue or more of a desire of Spacex to do things their own way?
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/11/2016 05:14 pm
Also, the larger issue is not the propellants but the COPV's.  People usually avoid areas near any type of container (even without overwrap) that is being pressurized into the 1000's of psi.
Title: Re: Falcon 9 (Future) speculation
Post by: Bob Shaw on 11/11/2016 05:21 pm
Nedelin. Rockets are dangerous.
Title: Re: Falcon 9 (Future) speculation
Post by: Stan-1967 on 11/11/2016 05:41 pm

AMOS-6 is serious problem because of the loss, but there is no reason to think being aware of where the edge of the envelope is and avoiding it is not an entire fix with no new metal cut.

Wrong, there may be other unknowns.  And also, what defines the "edge"?

I may very well be wrong, but as I understand Jim's posts in the last few pages as it relates to the importance of vehicle steady state, a steady state vehicle has a demarcation of vehicle failure probability that separates it from a vehicle with transient conditions.   It is commonly judged  as not prudent to have crew on board of a transient vehicle.  If you are proposing to put crew on board during transient conditions, you are proposing a questionable practice. 

When the transients contain unknown risk, it becomes an untenable decision based on the best current risk assessment practices.  The argument then moves to what is acceptable risk.  The "edge" seems to be where known acceptable risk intercepts with known probability of failure.  With transients, you never can fully test them all, so you can never have the assurance of a steady state situation.

As it relates to F9, the current thinking zeroing in on the COPV overwrap + solid 02 failure mode being transient, it is very real probability that in order to fix the failure mode, SpaceX needs to characterize the transients to a degree that may not be possible, and even if they do succeed in characterizing it, the solution may not accommodate using the existing COPV's.   

1.  The physics of the transient problem will push for lower pressure & larger COPV's.  This will cut into the benefit of chilled propellants by incurring mass/volume penalties within the O2 tank.

2.  SpaceX could adopt loading procedures with more gentle, predictable & characterized transients, however this would equate to a longer launch sequence, allowing the O2 to heat up, & remove the benefits of chilling.

I think a new COPV design could fix this problem, however whether its cut metal, or wound fibers, this is a very significant design change.   It may also introduce new failure modes not yet considered.  ( on top of the existing failure modes introduced by putting the COPV's into LOX).

I have a few questions for  the COPV & composite experts here:
1. Is it possible to make a COPV that insulates the inner lining?
2. Is it possible to make a COPV that brings LOX inside the COPV via a heat exchanger, to remove reliance on the COPV tank wall as the primary heat transfer surface?
3.  Do the above in the same form/fit/function as the existing COPV's

Title: Re: Falcon 9 (Future) speculation
Post by: Kansan52 on 11/11/2016 05:55 pm
So, if NASA says No to crew before fueling and SX can't fly the mission with that restraint, what penalties accrue if SX doesn't complete Commercial Crew?
Title: Re: Falcon 9 (Future) speculation
Post by: rocx on 11/11/2016 08:45 pm
Isn't an unfueled Falcon 9 in a steady state?
Title: Re: Falcon 9 (Future) speculation
Post by: old_sellsword on 11/11/2016 10:11 pm
Isn't an unfueled Falcon 9 in a steady state?

Yes. However the argument is that the crew will have to be strapped into the rocket while it is in an unsteady state (fueling), which is something NASA has never done.
Title: Re: Falcon 9 (Future) speculation
Post by: woods170 on 11/12/2016 11:13 am
So, if NASA says No to crew before fueling and SX can't fly the mission with that restraint, what penalties accrue if SX doesn't complete Commercial Crew?
They don't get paid and "their" missions will be awarded to the competition.
Title: Re: Falcon 9 (Future) speculation
Post by: John Alan on 11/12/2016 05:05 pm
I'm starting to think and hope Spacex will just add full flow top of tank return lines`to S1 and S2 LOX tanks and GSE to take that flow and recool and recirculate it while holding for hours if need be...
This would give them options while dealing with future Joe Blow 6-pack stray boaters, weather, and yes NASA's concerns as of late...

On edit
The time to start this change is now while planning LC-40 rebuild and finalizing V5 updates...
While not trivial to implement with GSE changes and two more lines to deal with on the rocket.
The weight penalty on the rocket should be minimal I believe...

Just my 2 cents,..  ;)
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/12/2016 05:13 pm
I starting to think and hope Spacex will just add full flow top of tank return lines`to S1 and S2 LOX tanks and GSE to take that flow and recool and recirculate it while holding for hours if need be...
This would give them options while dealing with future Joe Blow 6-pack stray boaters, weather, and yes NASA's concerns as of late...

Would add a lot of complexity to the vehicle, erector and GSE.
Title: Re: Falcon 9 (Future) speculation
Post by: John Alan on 11/12/2016 05:23 pm
I starting to think and hope Spacex will just add full flow top of tank return lines`to S1 and S2 LOX tanks and GSE to take that flow and recool and recirculate it while holding for hours if need be...
This would give them options while dealing with future Joe Blow 6-pack stray boaters, weather, and yes NASA's concerns as of late...

Would add a lot of complexity to the vehicle, erector and GSE.

I edited my post up above to clarify my thoughts on your concerns Jim
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/12/2016 06:26 pm

The time to start this change is now while planning LC-40 rebuild and finalizing V5 updates...
While not trivial to implement with GSE changes and two more lines to deal with on the rocket.
The weight penalty on the rocket should be minimal I believe...

No, because LC-39 and SLC-4 are up and running.  LC-40 doesn't even matter now.
Title: Re: Falcon 9 (Future) speculation
Post by: John Alan on 11/12/2016 08:34 pm

The time to start this change is now while planning LC-40 rebuild and finalizing V5 updates...
While not trivial to implement with GSE changes and two more lines to deal with on the rocket.
The weight penalty on the rocket should be minimal I believe...

No, because LC-39 and SLC-4 are up and running.  LC-40 doesn't even matter now.

Wow Jim... 2 months ago when I suggested not rebuilding LC-40...
You were saying... NO gotta have it...
Now this...  :o

To further clarify my thoughts...
When they rebuild LC-40... They should add the needed lines and equipment to GSE and the erector now...
Pilot and prove out the addition on LC-40 as F9 stages with the required stage mods come out of the factory...
Cap off the feature on stages going to LC-39 and SLC-4... for now...
AS TIME ALLOWS... and before flying manned missions off LC-39...
Upgrade LC-39 and later SLC-4 to uses the recirculating feature... 
There is plenty of time between launches to add in the feature to the other pads...
Do in parts if need be... Add piping... Add more... Add pumps... Tie in to current lines...
Spread mods out over 3 or 4 launches on each pad if need be...
Point is... this is doable... even if you (Jim) think I'm full of it...

EVERY problem has a solution... this idea puts a few OP issues to rest..
The above last few posts was me just putting an idea out there for discussion... nothing more..  ;)
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/12/2016 08:42 pm

When they rebuild LC-40... They should add the needed lines and equipment to GSE and the erector now...
Pilot and prove out the addition on LC-40 as F9 stages with the required stage mods come out of the factory...


There is no such thing as "Pilot and prove out the addition".  Can't be flying two types of vehicles at the same.  There isn't plenty of time to add the features.  It would take major mods to add it to the pads*.   It takes a stand down to convert pads and Spacex can't afford another standdown.   And that is the point about LC-40. Spacex needs to fly and not worry about pad updates.

* and McGregor


EVERY problem has a solution...

This isn't it
Basically, it is not doable.
Title: Re: Falcon 9 (Future) speculation
Post by: John Alan on 11/12/2016 08:46 pm
Then we agree to disagree... Have a nice weekend Jim...  :)
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/12/2016 08:47 pm
Then we agree to disagree... Have a nice weekend Jim...  :)

No, It is not a disagreement when one party is wrong.

Show me on here a place for upper umbilicals for the side boosters that would be exactly in the same place as the center booster.

It is a major undertaking and not just a flippant "oh, it should be easy adding a few lines, a few pumps and the flight hardware is not a major impact and we can do it on one pad but not the others but still have two production lines for different versions of stages, etc, etc, etc"

That is why it is not "doable'
Title: Re: Falcon 9 (Future) speculation
Post by: John Alan on 11/12/2016 08:54 pm
Then we agree to disagree... Have a nice weekend Jim...  :)

No, It is not a disagreement when one party is wrong.

Show me on here a place for upper umbilicals for the side boosters that would be exactly in the same place as the center booster

I never once said Falcon Heavy Jim... Did I...  ???
Cap or omit feature on FH boosters... stand down and reschedule if things go wrong in the count...

On edit...
The thread title says "speculation" Jim...
Not sure why you feel the need to act with like you are toward me...
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/12/2016 08:55 pm
Might as well adapt the pads to launch the Falcon 1 and ITS at the same time since it is so "doable"
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/12/2016 08:57 pm
I never once said Falcon Heavy Jim... Did I...  ???
Cap or omit feature on FH boosters... stand down and reschedule if things go wrong in the count...

All the vehicles are the same and hence by default it includes Falcon Heavy.  That is the Spacex MO.  They are not going to have different vehicles.

Can't not follow the Spacex MO when it doesn't suit your reasoning.
Title: Re: Falcon 9 (Future) speculation
Post by: John Alan on 11/12/2016 09:28 pm
I think SpaceX will 'adjust' their MO when it serves a purpose and need...

Again... I was just speculating an idea... You (Jim) clearly think the idea has NO merit...

That's fine...
But I do still think the idea has merit... even after your attempt to 'correct me'...

I'll let the other folks who read this website make up their own minds on this...  ;)

Title: Re: Falcon 9 (Future) speculation
Post by: Jcc on 11/13/2016 12:33 pm
The stages can be modified to include valves and fittings for the upper umbilical even if it is not used. For instance, if they provide the upper umbilicals for propellant recirculating at LC-39A but not the other pads, they can do the early fill and recirculating there, but the fast fill at the other pads and with FH.
That would require a stand down at LC-39A after LC-40 is back in operation and before crewed flights.

Not easy. None of this is easy.
Title: Re: Falcon 9 (Future) speculation
Post by: Dante80 on 11/14/2016 07:08 am
Might as well adapt the pads to launch the Falcon 1 and ITS at the same time since it is so "doable"

Jim, Ι know that you tend to comment on things that you know and have insight about. Here is a question though for this one. What do you think is going to happen or should happen? Will SpaceX and NASA find a way to incorporate the current v1.2 variant for CC (with densified propellants) or does SpaceX have to drop densifieds completely so as to get clearance for CC flights?
Title: Re: Falcon 9 (Future) speculation
Post by: envy887 on 11/14/2016 01:47 pm
My opinion on the likelihood of various solutions:

1) (most likely) SpaceX qualifies their current loading ops for CC by showing the risk is acceptably low, perhaps with minor changes that apply to all Falcon launches.
2) (possible) SpaceX introduces a version of Falcon (block 5?) that uses recirculating subcooled props for all launches, and stands down to implement the LV and GSE changes before CC.
3) (quite unlikely) SpaceX changes software and procedures to use boiling prop without hardware changes
4) (very highly unlikely) SpaceX introduces changes that differentiate the hardware on the crewed launches
Title: Re: Falcon 9 (Future) speculation
Post by: Kansan52 on 11/14/2016 08:51 pm
'ad·i·a·bat·ic

adjective

relating to or denoting a process or condition in which heat does not enter or leave the system concerned'

Just in case anyone else but doesn't know the definition!!
Title: Re: Falcon 9 (Future) speculation
Post by: te_atl on 11/16/2016 04:14 am
So after my previous responses to Jim, I did some "light" reading in the NASA archives for a refresher.  We've (and I include myself in this) that NASA didnt load crews until after fueling when the rocket was in steady state.  However, page 67 of http://www.jsc.nasa.gov/history/mission_trans/MA06_TEC.PDF (http://www.jsc.nasa.gov/history/mission_trans/MA06_TEC.PDF) actually records that John Glenn boarded at T-120 minutes, mechanical closeouts were done from T-90 minutes to t-55 Minutes, and..  here was my surprise.  That document says that LOX tanking fill BEGAN at T-35 Minutes.   So Glenn was sitting in the spacecraft while it was being filled with LOX, which means the vehicle wasn't in steady state.   Did I read this thing wrong or did they really tank LOX after the astronaut boarded?   If they did, then there's precedence for boarding before tanking is complete.  If I read this right, then to match the Mercury sequence, SpaceX would only need to load RP-1 first, then load crew, then tank with LOX.
Title: Re: Falcon 9 (Future) speculation
Post by: douglas100 on 11/16/2016 09:21 am

.....Did I read this thing wrong or did they really tank LOX after the astronaut boarded?   If they did, then there's precedence for boarding before tanking is complete.  If I read this right, then to match the Mercury sequence, SpaceX would only need to load RP-1 first, then load crew, then tank with LOX.

I believe you read it correctly. There is a precedent, but it is not really relevant to F9. Atlas did not use sub-cooled LOX and did not have COPV's in the LOX tanks. The apparent cause of the F9 accident did not exist in Mercury Atlas. This discussion perhaps better belongs in http://forum.nasaspaceflight.com/index.php?topic=41587.0 (http://forum.nasaspaceflight.com/index.php?topic=41587.0)
Title: Re: Falcon 9 (Future) speculation
Post by: woods170 on 11/16/2016 01:43 pm

.....Did I read this thing wrong or did they really tank LOX after the astronaut boarded?   If they did, then there's precedence for boarding before tanking is complete.  If I read this right, then to match the Mercury sequence, SpaceX would only need to load RP-1 first, then load crew, then tank with LOX.

I believe you read it correctly. There is a precedent, but it is not really relevant to F9. Atlas did not use sub-cooled LOX and did not have COPV's in the LOX tanks. The apparent cause of the F9 accident did not exist in Mercury Atlas. This discussion perhaps better belongs in http://forum.nasaspaceflight.com/index.php?topic=41587.0 (http://forum.nasaspaceflight.com/index.php?topic=41587.0)
The lack of use of sub-cooled LOX on Atlas and the lack of presence of COPV's on Atlas is beside the point. Jim's entire argument is about getting the vehicle in a stable situation with leveled-off temps on the vehicle, before getting the crew on-board. Basically he's saying: Fuel the vehicle, let it settle to a stable situation, then board the crew.
No such thing was the case on MA-6 thru MA-9.
Title: Re: Falcon 9 (Future) speculation
Post by: docmordrid on 11/17/2016 04:02 am
Also, the larger issue is not the propellants but the COPV's.  People usually avoid areas near any type of container (even without overwrap) that is being pressurized into the 1000's of psi.

High pressure dive tanks go to 3300 to 3500 psi, welding tanks 4,500 psi. High pressure portable medical O2 tanks 2,000 psi, and you may be next to one in the grocery store.
Title: Re: Falcon 9 (Future) speculation
Post by: HMXHMX on 11/17/2016 06:10 am
Also, the larger issue is not the propellants but the COPV's.  People usually avoid areas near any type of container (even without overwrap) that is being pressurized into the 1000's of psi.

High pressure dive tanks go to 3300 to 3500 psi, welding tanks 4,500 psi. High pressure portable medical O2 tanks 2,000 psi, and you may be next to one in the grocery store.

Firefighter's breathing O2 goes to 4500 psia.
Title: Re: Falcon 9 (Future) speculation
Post by: Jarnis on 11/17/2016 10:40 am
Also, the larger issue is not the propellants but the COPV's.  People usually avoid areas near any type of container (even without overwrap) that is being pressurized into the 1000's of psi.

High pressure dive tanks go to 3300 to 3500 psi, welding tanks 4,500 psi. High pressure portable medical O2 tanks 2,000 psi, and you may be next to one in the grocery store.

Firefighter's breathing O2 goes to 4500 psia.

Pretty sure they just use compressed air, not O2.
Title: Re: Falcon 9 (Future) speculation
Post by: Jim on 11/17/2016 01:26 pm
Also, the larger issue is not the propellants but the COPV's.  People usually avoid areas near any type of container (even without overwrap) that is being pressurized into the 1000's of psi.

High pressure dive tanks go to 3300 to 3500 psi, welding tanks 4,500 psi. High pressure portable medical O2 tanks 2,000 psi, and you may be next to one in the grocery store.

Read again.  I didn't say go near the tanks that are pressurized.  I said "that is being pressurized".  There is a big difference in the two statements as well as the safety equipment that is used for both
Title: Re: Falcon 9 (Future) speculation
Post by: HMXHMX on 11/17/2016 03:39 pm
Also, the larger issue is not the propellants but the COPV's.  People usually avoid areas near any type of container (even without overwrap) that is being pressurized into the 1000's of psi.

High pressure dive tanks go to 3300 to 3500 psi, welding tanks 4,500 psi. High pressure portable medical O2 tanks 2,000 psi, and you may be next to one in the grocery store.

Firefighter's breathing O2 goes to 4500 psia.



Pretty sure they just use compressed air, not O2.

Thanks for the correction; I was sloppy in wording.  Nevertheless, the point was using high pressure bottles with adequate safety factors in direct proximity to humans.  We do that all the time.  We also fill those bottles in proximity to humans, taking appropriate precautions.
Title: Re: Falcon 9 (Future) speculation
Post by: envy887 on 11/17/2016 04:13 pm
... We also fill those bottles in proximity to humans, taking appropriate precautions.

The bottles relevant in this thread are submerged in LOX sitting atop 40 tons of kerosene. It's a bit harder to take any useful precautions in this scenario (compared to the back room of a scuba shop), since any catastrophic pressurized failure almost certainly means a LOV.
Title: Re: Falcon 9 (Future) speculation
Post by: HMXHMX on 11/18/2016 07:12 pm
... We also fill those bottles in proximity to humans, taking appropriate precautions.

The bottles relevant in this thread are submerged in LOX sitting atop 40 tons of kerosene. It's a bit harder to take any useful precautions in this scenario (compared to the back room of a scuba shop), since any catastrophic pressurized failure almost certainly means a LOV.

No argument with that.  But pretty much any COPV failure will cause LOV, given current vehicle designs.
Title: Re: Falcon 9 (Future) speculation
Post by: Jcc on 11/18/2016 09:14 pm
My opinion on the likelihood of various solutions:

1) (most likely) SpaceX qualifies their current loading ops for CC by showing the risk is acceptably low, perhaps with minor changes that apply to all Falcon launches.
2) (possible) SpaceX introduces a version of Falcon (block 5?) that uses recirculating subcooled props for all launches, and stands down to implement the LV and GSE changes before CC.
3) (quite unlikely) SpaceX changes software and procedures to use boiling prop without hardware changes
4) (very highly unlikely) SpaceX introduces changes that differentiate the hardware on the crewed launches

This list is missing one option: that all vehicles get hardware for recirculation so there are not multiple versions of the vehicles, but that there are two optional fueling procedures, early load and recirculation, which requires upper umbilicals, and late load, where upper umbilicals are not attached and the valves stay closed.

Precedence in SpaceX MO? Putting leg attach points on all v1.1 stage 1, but only attaching legs where recovery testing was possible.
Title: Re: Falcon 9 (Future) speculation
Post by: envy887 on 11/18/2016 10:48 pm
If recirculation is qualified there's little reason to not use it on every launch. It makes holding through long launch windows and recycling after a scrub much easier.
Title: Re: Falcon 9 (Future) speculation
Post by: Doesitfloat on 11/21/2016 08:49 pm
My opinion on the likelihood of various solutions:

1) (most likely) SpaceX qualifies their current loading ops for CC by showing the risk is acceptably low, perhaps with minor changes that apply to all Falcon launches.
2) (possible) SpaceX introduces a version of Falcon (block 5?) that uses recirculating subcooled props for all launches, and stands down to implement the LV and GSE changes before CC.
3) (quite unlikely) SpaceX changes software and procedures to use boiling prop without hardware changes
4) (very highly unlikely) SpaceX introduces changes that differentiate the hardware on the crewed launches

I think one more option needs to be added:

5) The Falcon Heavy Center core configuration has hardware incorporated to allow subcooled propellants to be loaded earlier. The Commercial Crew Program office released a presentation back in September that said the Crew Dragon would use the same core a the Falcon Heavy center core.  Most of the posts on this site thought this was a mistake and the program office "meant" the side boosters.  Recently Kathy Lueders the Manager the Commercial Crew Program released a progress report that again said the Crew Dragon will use the same core as the Falcon Heavy Center.  Perhaps this center core is not a mistake and there is a good reason to use that core.
Title: Re: Falcon 9 (Future) speculation
Post by: old_sellsword on 11/21/2016 09:47 pm
The Commercial Crew Program office released a presentation back in September that said the Crew Dragon would use the same core a the Falcon Heavy center core. Most of the posts on this site thought this was a mistake and the program office "meant" the side boosters. Recently Kathy Lueders the Manager the Commercial Crew Program released a progress report that again said the Crew Dragon will use the same core as the Falcon Heavy Center.

1. The picture you attached does not mention either a side booster or center core, it simply says "Common first stage with Falcon Heavy design." First stage is a vague term and doesn't necessarily mean center core, and they could've also just been referring to general design and manufacturing processes.

2. They are currently converting a first stage (B1023, F9-025, Thaicom 8) into a FH side booster. This means that the current version of Falcon 9 already has thick enough tank walls to be a FH side booster. There is some debate as to whether or not the FH center core will need thicker tank walls to transfer the loads.

It would make more sense to have the FH side boosters be Falcon 9 first stages because the demand for Falcon 9 is way higher than that of Falcon Heavy. If you made Falcon 9 be the FH center core, then you'd have twice as many FH side boosters sitting around doing nothing while Falcon 9s launch. Since there are two side boosters per Falcon Heavy, let the more numerous variant double as your standard launch vehicle.
Title: Re: Falcon 9 (Future) speculation
Post by: rabe0070 on 11/22/2016 12:48 am

1. The picture you attached does not mention either a side booster or center core, it simply says "Common first stage with Falcon Heavy design." First stage is a vague term and doesn't necessarily mean center core, and they could've also just been referring to general design and manufacturing processes.

Would they need to specify it as common to FH if it was not the center stage (assuming the side boosters are regular F9s)?
Title: Re: Falcon 9 (Future) speculation
Post by: old_sellsword on 11/22/2016 02:31 am

1. The picture you attached does not mention either a side booster or center core, it simply says "Common first stage with Falcon Heavy design." First stage is a vague term and doesn't necessarily mean center core, and they could've also just been referring to general design and manufacturing processes.

Would they need to specify it as common to FH if it was not the center stage (assuming the side boosters are regular F9s)?

I don't see why not. Falcon 9 doubling as a FH side booster is just as noteworthy as it doubling as the FH center core.
Title: Re: Falcon 9 (Future) speculation
Post by: Jcc on 11/22/2016 03:26 pm
What I understand from it is that the Crew F9 is identical to any single stick F9, and also the center core of FH. It implies some potential differences for the side boosters, otherwise they would say it was common to all 3 FH boosters.
Title: Re: Falcon 9 (Future) speculation
Post by: mvpel on 12/01/2016 04:51 pm
What I understand from it is that the Crew F9 is identical to any single stick F9, and also the center core of FH. It implies some potential differences for the side boosters, otherwise they would say it was common to all 3 FH boosters.

Perhaps the "buffed up" (as Elon put it) Falcon Heavy center core provides additional structural safety margin and can, with the improved Merlin efficiency, still deliver all the dV needed by the Crew Dragon and RTLS?
Title: Re: Falcon 9 (Future) speculation
Post by: Req on 01/22/2017 12:59 am
Quote
George ‏@gdoehne
@elonmusk Next SpaceX flight (Echostar) has v heavy GTO payload (5500kg)
Will Falcon fly expendable, or try low-margin droneship landing?

Elon Musk ‏@elonmusk
@gdoehne Expendable. Future flights will go on Falcon Heavy or the upgraded Falcon 9.

George ‏@gdoehne
@elonmusk When you say upgraded Falcon 9 are you referring to the Block 5 you mentioned here? Timing fits.

Elon Musk ‏@elonmusk
Yes. Block 5 is the final upgrade of the Falcon architecture. Significantly improves performance & ease of reusability. Flies end of year.

https://twitter.com/elonmusk/status/822985910782283776
Title: Re: Falcon 9 (Future) speculation
Post by: FutureSpaceTourist on 01/22/2017 07:26 am
So Echostar is the last planned expendable F9 launch; quite a milestone 

Would love to know more about what SpaceX has learned from the returned boosters to help with ease of re-use. Hopefully we'll find out more in time.

Clearly as block 5 is the last F9 variant, there must be more COPV changes in it. So no matter how many successful launches SpaceX has before then, it won't mean very much from a reliability POV. Makes me nervous ...
Title: Re: Falcon 9 (Future) speculation
Post by: Kaputnik on 01/22/2017 11:17 am
The Commercial Crew Program office released a presentation back in September that said the Crew Dragon would use the same core a the Falcon Heavy center core. Most of the posts on this site thought this was a mistake and the program office "meant" the side boosters. Recently Kathy Lueders the Manager the Commercial Crew Program released a progress report that again said the Crew Dragon will use the same core as the Falcon Heavy Center.

1. The picture you attached does not mention either a side booster or center core, it simply says "Common first stage with Falcon Heavy design." First stage is a vague term and doesn't necessarily mean center core, and they could've also just been referring to general design and manufacturing processes.

2. They are currently converting a first stage (B1023, F9-025, Thaicom 8) into a FH side booster. This means that the current version of Falcon 9 already has thick enough tank walls to be a FH side booster. There is some debate as to whether or not the FH center core will need thicker tank walls to transfer the loads.

It would make more sense to have the FH side boosters be Falcon 9 first stages because the demand for Falcon 9 is way higher than that of Falcon Heavy. If you made Falcon 9 be the FH center core, then you'd have twice as many FH side boosters sitting around doing nothing while Falcon 9s launch. Since there are two side boosters per Falcon Heavy, let the more numerous variant double as your standard launch vehicle.

OTOH, they will expect to recover almost all of the side boosters, and expend at least some of the centre cores. So perhaps it makes more sense for the side boosters to be the one-offs and the centre core to be in continuous production, serving as both F9 and FH core.
Title: Re: Falcon 9 (Future) speculation
Post by: Ionmars on 01/22/2017 12:54 pm
Autogenous pressurization

Just read the first 10 pages of this thread and didn't see this technique specifically listed as an expected improvement in the next F9 upgrade. It would seem to be very desirable to use the propellant ullage in each tank to pressurize the tank during engine firing. This eliminates the necessity of an extra gas (He) and in particular, eliminates the need for COPVs. Since the last two RUDs were related to this particular item, I would think that their elimination would deserve a really high priority. Since the SSME employed an autogenous pressurization technique, the TRL is not zero. Furthermore, Spacex is planning to employ this technique in the ITS.

Does anyone know a reason why Spacex would not be furiously working this out for the F9?
Title: Re: Falcon 9 (Future) speculation
Post by: Robotbeat on 01/22/2017 12:59 pm
So Echostar is the last planned expendable F9 launch; quite a milestone 

Would love to know more about what SpaceX has learned from the returned boosters to help with ease of re-use. Hopefully we'll find out more in time.

Clearly as block 5 is the last F9 variant, there must be more COPV changes in it. So no matter how many successful launches SpaceX has before then, it won't mean very much from a reliability POV. Makes me nervous ...
Dont think he quite said it's the last expendable. I think there will be at least one more due to Reddit comments.
Title: Re: Falcon 9 (Future) speculation
Post by: brickmack on 01/22/2017 01:43 pm
Autogenous pressurization

Just read the first 10 pages of this thread and didn't see this technique specifically listed as an expected improvement in the next F9 upgrade. It would seem to be very desirable to use the propellant ullage in each tank to pressurize the tank during engine firing. This eliminates the necessity of an extra gas (He) and in particular, eliminates the need for COPVs. Since the last two RUDs were related to this particular item, I would think that their elimination would deserve a really high priority. Since the SSME employed an autogenous pressurization technique, the TRL is not zero. Furthermore, Spacex is planning to employ this technique in the ITS.

Does anyone know a reason why Spacex would not be furiously working this out for the F9?

Can't be done. Kerosene doesn't gassify like that.
Title: Re: Falcon 9 (Future) speculation
Post by: OnWithTheShow on 01/22/2017 02:34 pm
Posting this reply to a comment in Echostar 23 thread here as it fits better. Comments came after we found out Echostar 23 would be an expendable launch....

Well to some extent this expendable launch would have been a good candidate for a reused booster

Im sure they are lobbying manifest customers hard to move expendable sats to reused "block 4" F9's. They will probably have more luck if SES-10 gets off successfully (and returns successfully for post reflight analysis). Once block 5 debuts they probably would want to retire the block 4 boosters.
Title: Re: Falcon 9 (Future) speculation
Post by: Ionmars on 01/22/2017 04:43 pm
Autogenous pressurization

Just read the first 10 pages of this thread and didn't see this technique specifically listed as an expected improvement in the next F9 upgrade. It would seem to be very desirable to use the propellant ullage in each tank to pressurize the tank during engine firing. This eliminates the necessity of an extra gas (He) and in particular, eliminates the need for COPVs. Since the last two RUDs were related to this particular item, I would think that their elimination would deserve a really high priority. Since the SSME employed an autogenous pressurization technique, the TRL is not zero. Furthermore, Spacex is planning to employ this technique in the ITS.

Does anyone know a reason why Spacex would not be furiously working this out for the F9?

Can't be done. Kerosene doesn't gassify like that.
Works for LOX, and that's the main problem for F9 S2.
Title: Re: Falcon 9 (Future) speculation
Post by: Robotbeat on 01/22/2017 04:47 pm
Autogenous pressurization

Just read the first 10 pages of this thread and didn't see this technique specifically listed as an expected improvement in the next F9 upgrade. It would seem to be very desirable to use the propellant ullage in each tank to pressurize the tank during engine firing. This eliminates the necessity of an extra gas (He) and in particular, eliminates the need for COPVs. Since the last two RUDs were related to this particular item, I would think that their elimination would deserve a really high priority. Since the SSME employed an autogenous pressurization technique, the TRL is not zero. Furthermore, Spacex is planning to employ this technique in the ITS.

Does anyone know a reason why Spacex would not be furiously working this out for the F9?

Can't be done. Kerosene doesn't gassify like that.
Works for LOX, and that's the main problem for F9 S2.
No, the pressurization gas for both the oxygen and the kerosene is kept in the LOx tank. The cryogenic temperature mean you can store multiple times as much gas in the LOx tank than in kerosene or outside for the same tank mass.
Title: Re: Falcon 9 (Future) speculation
Post by: Space Ghost 1962 on 01/22/2017 09:22 pm
Suggest that the operational point of F9/FH is:
 * F9 RTLS for <3T IMLEO
 * F9 barge for < 5T GTO 1800 (TBD with 5)
 * FH RTLS / core barge < 50T

Past that its refinements for launch cost/frequency/reliability as a "done" system. We'll see if it happens.

Everything else is about Mars/BFS/BFR.
Title: Re: Falcon 9 (Future) speculation
Post by: deruch on 01/23/2017 03:38 am
Suggest that the operational point of F9/FH is:
 * F9 RTLS for <3T IMLEO
 * F9 barge for < 5T GTO 1800 (TBD with 5)
 * FH RTLS / core barge < 50T

Past that its refinements for launch cost/frequency/reliability as a "done" system. We'll see if it happens.

Everything else is about Mars/BFS/BFR.
With high reliability RTLS recovery, it may make better sense to eliminate F9 barge landings and move all launches that would need it to FH RTLS.  Then the ASDS only gets used for FH center core on missions that need it.  This would reduce the damage to cores and therefore improve SpaceX's refurbishment costs.  As well as reducing the number of missions that require ASDS, thereby reducing operational costs.
Title: Re: Falcon 9 (Future) speculation
Post by: Space Ghost 1962 on 01/23/2017 04:05 am
Suggest that the operational point of F9/FH is:
 * F9 RTLS for <3T IMLEO
 * F9 barge for < 5T GTO 1800 (TBD with 5)
 * FH RTLS / core barge < 50T

Past that its refinements for launch cost/frequency/reliability as a "done" system. We'll see if it happens.

Everything else is about Mars/BFS/BFR.

With high reliability RTLS recovery, it may make better sense to eliminate F9 barge landings and move all launches that would need it to FH RTLS.  Then the ASDS only gets used for FH center core on missions that need it.  This would reduce the damage to cores and therefore improve SpaceX's refurbishment costs.  As well as reducing the number of missions that require ASDS, thereby reducing operational costs.
Perhaps.

Depends on how the effectiveness of block 5 works out, because then you'll get some idea of the reuse time/cost per each of the two classes of cores. As well as getting the time/cost of FH.

If both were fast/cheap enough, you'd bias your model towards RTLS for most missions to increase launch frequency as the guiding light.

In any case, the driving factor here in operations cost would be how the manifest changes as tempo increases, and I'm afraid all our crystal balls are a bit cloudy at the moment on that particular matter.

It's kind of hard seeing much increase in GEO payloads beyond a certain point, there are only so many LEO constellations, and other sources of payloads don't seem to be on the rise either. If they are mostly small/low-no C3 - optimize for F9 RTLS. If there's enough > 5T loads, then FH RTLS is the entire focus. If launch frequency dries up, F9 RTLS for most, occasional F9 barge, and even less frequent FH RTLS.

After that, the priority would shift to improving core economics. But keep in mind ...

What drives the "Future" in this thread is, at the very bottom of things ... is the future of payloads.
Title: Re: Falcon 9 (Future) speculation
Post by: wannamoonbase on 01/23/2017 03:37 pm
F9 speculation is that we are seeing a 95% evolved vehicle currently.

Improvements will be bumping:

The engines to their final performance.
Re-entry survivability
Ease of Reuse

Despite Elon stating this will be the final configuration of the Falcon family, nothing in SpaceX's history indicates they won't tinker as things are learned.

I can see ground operations improvements continuing to evolve.  Such as with the ASDS, faster tug or a purpose built self propelled vessel etc.
Title: Re: Falcon 9 (Future) speculation
Post by: DOCinCT on 01/23/2017 04:10 pm
Suggest that the operational point of F9/FH is:
 * F9 RTLS for <3T IMLEO
 * F9 barge for < 5T GTO 1800 (TBD with 5)
 * FH RTLS / core barge < 50T
The 50 tons for FH  or 25 tons for F9 is theoretical as both vehicles are currently constrained by the limitation of the existing fairing, i.e., inner diameter: 4.6m  cylindrical length: 6.7m (length before taper begins) and enhanced PAF 12 tons.  While either could launch an ISS Destiny class module, the fairing is far too short (Destiny 8.5 m long) and the weight of an ISS Leonardo module far exceeds the PAF capacity (but within the the size contraints).
SpaceX will need to engineer and build a much better fairing combination if they wish to really be a heavy lift launch company.
Title: Re: Falcon 9 (Future) speculation
Post by: Robotbeat on 01/23/2017 04:19 pm
Or use it to launch stuff like propellant.
Title: Re: Falcon 9 (Future) speculation
Post by: Space Ghost 1962 on 01/23/2017 07:11 pm
The 50 tons for FH  or 25 tons for F9 is theoretical as both vehicles are currently constrained by the limitation of the existing fairing, i.e., inner diameter: 4.6m  cylindrical length: 6.7m (length before taper begins) and enhanced PAF 12 tons.
As payload weight/density increases, the frequency of such payloads drops.

To support any new fairing/PAF (and associate payload processing/handling BTW!) you need an acceptable number of payloads to cost justify such.

Quote
While either could launch an ISS Destiny class module, the fairing is far too short (Destiny 8.5 m long) and the weight of an ISS Leonardo module far exceeds the PAF capacity (but within the the size constraints).
First off, apart from the Russians, SX is the only firm that has launched a new module to the ISS.

And they didn't use a fairing/PAF to do so ;) .

Also, Musk said many years ago that SX would build as big a trunk as needed. Perhaps one could deliver a module that way?

Quote
SpaceX will need to engineer and build a much better fairing combination if they wish to really be a heavy lift launch company.
Nope. Wrong way round.

They have excess capacity with FH. That advertises for payload beyond EELV/Ariane. The few payloads that are attracted by that will not be 2-3 year before flight, but 4-6 years. SX would commit to proving the needed capability as part of the launch contract, demonstrate it well before payload is qualified for flight.

Or use it to launch stuff like propellant.

Yes. Which might be with a modified stage, trunk, or Dragon component, depending on where the consumable is being delivered, and if it needs to be preserved/replenished indefinitely awaiting use.
Title: Re: Falcon 9 (Future) speculation
Post by: Ionmars on 01/24/2017 09:20 pm
Can't be done. Kerosene doesn't gassify like that.
Works for LOX, and that's the main problem for F9 S2.
No, the pressurization gas for both the oxygen and the kerosene is kept in the LOx tank. The cryogenic temperature mean you can store multiple times as much gas in the LOx tank than in kerosene or outside for the same tank mass.
Huh, Now I know.