Author Topic: SpaceX customers' views on reuse  (Read 170646 times)

Online oldAtlas_Eguy

  • Senior Member
  • *****
  • Posts: 3535
  • Florida
  • Liked: 1944
  • Likes Given: 237
Re: SpaceX customers' views on reuse
« Reply #560 on: 07/15/2018 07:58 PM »
All B5 cores can serve as a FH center core. This was confirmed a few weeks ago.
Do you have a source for that? The only public information tells us that any B5 F9 first stage can be used as a FH side-boorster, but that FH cores are very different.

There is public information that block 4 S1 can be converted to a block 4 FH booster, and that the block 4 FH core was a special build. There is no such information for block 5, but I can tell you from my analysis of the FH demo mission that the core stage either had a lot of unused propellant, or it had a lot more dry mass than a regular block 4 stage. Similarly, from the block 5 Bangabandhu-1 mission, either it ran at less than 100% thrust, and also had a lot of unused propellant, or it had a similar dry mass to the FH demo core stage. This is admittedly not hard proof, but I do suspect that all block 5 first stages are structurally similar. This may have been deemed necessary to meet the 1.4 factor of safety requirement for the commercial crew program.
Yes it would make sense to use a BLK5 structure design for the FH demo core but we do not have any confirmation on that. Plus they would need to do a demonstration on the BLK5 structure changes including a qual test of structure strength. It definitely would make sense to combine this use of the FH demo core flight as another data point to validate the dry weight/structure for BLK5 prior to a full up BLK5 operational flight. They would even gather landing data related to the problems with landing a heavier stage.

But we still do not have any real confirmation on our sensible conclusions.

It is still possible that the FH core tank is still heavier and stronger than a standard BLK5, but with all the same other hardware.

So now back to customers views on reuse.

The customers want a large baseline (flights) of a single design and not significant variants. Having a FH core stage as a significant variant from the standard BLK5 would make customers uncomfortable with using a stage that would have very low flight numbers and not fly very often (a couple of times a year as in 1 to 4 vs F9 standard BLK5 at 20 to 50 times a year).

Offline john smith 19

  • Senior Member
  • *****
  • Posts: 7654
  • Everyplaceelse
  • Liked: 1215
  • Likes Given: 8220
Re: SpaceX customers' views on reuse
« Reply #561 on: 07/19/2018 05:48 AM »
So now back to customers views on reuse.

The customers want a large baseline (flights) of a single design and not significant variants. Having a FH core stage as a significant variant from the standard BLK5 would make customers uncomfortable with using a stage that would have very low flight numbers and not fly very often (a couple of times a year as in 1 to 4 vs F9 standard BLK5 at 20 to 50 times a year).
That's the issue. As usual it's back when does "small changes" become "complete redesign" ?

BFS. The worlds first Methane fueled FFORSC engined CFRP structured A380 sized aerospaceplane tail sitter capable of flying in Earth and Mars atmospheres. BFR. The worlds biggest Methane fueled FFORSC engined CFRP structured booster for BFS. First flight to Mars by end of 2022. Forward looking statements. T&C apply. Believe no one. Run your own numbers. So, you are going to Mars to start a better life? Picture it in your mind. Now say what it is out loud.

Online FutureSpaceTourist

  • Senior Member
  • *****
  • Posts: 6862
  • UK
    • Plan 28
  • Liked: 6760
  • Likes Given: 2105
Re: SpaceX customers' views on reuse
« Reply #562 on: 08/03/2018 02:02 AM »
As far as Im aware its not yet been announced that the Merah Putih launch is the first block 5 re-use and yet:

And I have visual confirmation from Tom Cross that the booster is indeed sooty and thus B1046.2 :) photos incoming.

Edit: the tweet!
https://twitter.com/_TomCross_/status/1025074341040533504



Offline JamesH65

  • Full Member
  • ****
  • Posts: 917
  • Liked: 606
  • Likes Given: 8
Re: SpaceX customers' views on reuse
« Reply #563 on: 08/03/2018 11:57 AM »
So now back to customers views on reuse.

The customers want a large baseline (flights) of a single design and not significant variants. Having a FH core stage as a significant variant from the standard BLK5 would make customers uncomfortable with using a stage that would have very low flight numbers and not fly very often (a couple of times a year as in 1 to 4 vs F9 standard BLK5 at 20 to 50 times a year).
That's the issue. As usual it's back when does "small changes" become "complete redesign" ?

Same as any other rocket manufacturer. They all change some bits after each flight as they find issues. I bet even some smaller parts are 'completely redesigned', rather than just modified. As for when the cummulative total of all these changes means its actually a a new rocket, well, that's a matter of opinion. When the manufacturer says so would be mine.

Online FutureSpaceTourist

  • Senior Member
  • *****
  • Posts: 6862
  • UK
    • Plan 28
  • Liked: 6760
  • Likes Given: 2105
Re: SpaceX customers' views on reuse
« Reply #564 on: 08/03/2018 01:14 PM »
For completeness of this thread (and as noted by crandles57) NSFs SAOCOM 1A article 2 days ago about the first West Coast RTLS launch includes:

Quote from: https://www.nasaspaceflight.com/2018/08/saocom-1a-ships-vandenberg-falcon-9-first-west-coast-rtls/
The booster that will be used to perform the first land landing on the west coast is B1048.2 which previously flew Iridium-7 on July 25th. The change to a flight-proven booster was finalized only a few weeks ago.

Offline Nomadd

  • Senior Member
  • *****
  • Posts: 3364
  • Boca Chica, Texas
  • Liked: 6050
  • Likes Given: 361
Re: SpaceX customers' views on reuse
« Reply #565 on: 08/03/2018 02:41 PM »


The customers want a large baseline (flights) of a single design and not significant variants. Having a FH core stage as a significant variant from the standard BLK5 would make customers uncomfortable with using a stage that would have very low flight numbers and not fly very often (a couple of times a year as in 1 to 4 vs F9 standard BLK5 at 20 to 50 times a year).
Maybe you can't fly a standard F9 as an FH core, but is there any reason they can't use an FH core as an F9? A few extra tons of dry weight isn't going to affect payload that much.
« Last Edit: 08/03/2018 02:42 PM by Nomadd »

Offline Tomness

  • Full Member
  • **
  • Posts: 262
  • Into the abyss will I run
  • Liked: 65
  • Likes Given: 336
Re: SpaceX customers' views on reuse
« Reply #566 on: 08/03/2018 03:02 PM »


The customers want a large baseline (flights) of a single design and not significant variants. Having a FH core stage as a significant variant from the standard BLK5 would make customers uncomfortable with using a stage that would have very low flight numbers and not fly very often (a couple of times a year as in 1 to 4 vs F9 standard BLK5 at 20 to 50 times a year).
Maybe you can't fly a standard F9 as an FH core, but is there any reason they can't use an FH core as an F9? A few extra tons of dry weight isn't going to affect payload that much.
How about on that token, you need FH Booster, convert, you need F9 convert again. maybe that could swap them or just keep FH stored.

Offline edzieba

  • Virtual Realist
  • Full Member
  • ***
  • Posts: 314
  • United Kingdom
  • Liked: 317
  • Likes Given: 30
Re: SpaceX customers' views on reuse
« Reply #567 on: 08/07/2018 03:20 PM »


The customers want a large baseline (flights) of a single design and not significant variants. Having a FH core stage as a significant variant from the standard BLK5 would make customers uncomfortable with using a stage that would have very low flight numbers and not fly very often (a couple of times a year as in 1 to 4 vs F9 standard BLK5 at 20 to 50 times a year).
Maybe you can't fly a standard F9 as an FH core, but is there any reason they can't use an FH core as an F9? A few extra tons of dry weight isn't going to affect payload that much.
How about on that token, you need FH Booster, convert, you need F9 convert again. maybe that could swap them or just keep FH stored.
That depends on just how much of a F9 needs to be changed to create a FH centre core.
If it's just a matter of replacing components of the (bolt together) Octaweb and swapping out the interstage for one with the pusher hardware - i.e. the same sort of 'conversion' to turn a regular F9 core to a FH side core - then potentially any core can become a FH centre core just as any core can become a FH side core. This was rumoured from a few different sources, but has been shot down recently by Elon.
If the actual tank structure of an FH centre core is significantly strengthened from a regular F9 or FH side core, then while you could in theory swap in regular F9 octaweb and interstage hardware (or at the very least, swap in the specific octaweb segments that contain the 'missing' holddowns), then not only would you be losing some margin from lugging around that extra structural mass but you risk a core that cannot be as easily subbed out for another as is possible with a 'standard' core.

Offline sghill

  • Full Member
  • ****
  • Posts: 1408
  • United States
  • Liked: 1575
  • Likes Given: 2311
Re: SpaceX customers' views on reuse
« Reply #568 on: 08/10/2018 12:38 AM »
Quote from: john smith 19

From the customers PoV reuse only matters to them when it
a) Changes the price over a new build booster
b) Changes the reliability WRT  a new build booster.

You left out a critical 3rd one.

C) Changes booster availability and launch dates.

A customer who can launch their bird this year or next on a used booster is going to save millions over the carrying cost of waiting several years with their payload in storage for an assembly line to churn out a new one.
« Last Edit: 08/10/2018 12:42 AM by sghill »
Bring the thunder!

Offline Lar

  • Fan boy at large
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 10799
  • Saw Gemini live on TV
  • A large LEGO storage facility ... in Michigan
  • Liked: 7722
  • Likes Given: 5578
Re: SpaceX customers' views on reuse
« Reply #569 on: 08/10/2018 02:27 AM »
the one failure (not crash, failure) was from a development/test flight, not a production one, since the FH center core was coming back from a much tougher flight regime.
Much tougher? Wouldn't that have an effect on the stress and thermal loads, rather than engine reignition?
ISTR statements by SpaceX that the center core ran out of starter fluid because earlier starts used more, and that was because they had to start the engines during a tougher flight regime.

So yes, what I said was correct.

But too much FH failure analysis is probably off topic.
"I think it would be great to be born on Earth and to die on Mars. Just hopefully not at the point of impact." -Elon Musk
"We're a little bit like the dog who caught the bus" - Musk after CRS-8 S1 successfully landed on ASDS OCISLY

Online FutureSpaceTourist

  • Senior Member
  • *****
  • Posts: 6862
  • UK
    • Plan 28
  • Liked: 6760
  • Likes Given: 2105
Re: SpaceX customers' views on reuse
« Reply #570 on: 08/30/2018 10:10 AM »
Basic economics and the political realities of funding available for NASA mean that there's nothing suprising in the views Jim Bridenstine expressed, but still noteworthy that he said them and made only the briefest mention of SLS:

Quote
NASA head hints that reusable rocket cos. like SpaceX will enable Moon return

By Eric Ralph
Posted on August 30, 2018

In a series of thoroughly unexpected and impassioned introductory remarks at one of several 2018 Advisory Council meetings, NASA administrator Jim Bridenstine bucked at least two decades of norms by all but explicitly stating that reusable rockets built by innovative private companies like SpaceX and Blue Origin will enable the true future of space exploration.

https://www.teslarati.com/nasa-head-reusable-rockets-spacex-blue-origin-future/


Offline marsbase

  • Member
  • Posts: 74
  • North Carolina
  • Liked: 45
  • Likes Given: 13
Re: SpaceX customers' views on reuse
« Reply #571 on: 08/30/2018 03:40 PM »
And once he wins the "sustainability wars" he will be able to make the next shift.  "Oh, did I say moon?  A slip of the tongue.  I meant to say Mars."  :)

Offline john smith 19

  • Senior Member
  • *****
  • Posts: 7654
  • Everyplaceelse
  • Liked: 1215
  • Likes Given: 8220
Re: SpaceX customers' views on reuse
« Reply #572 on: 09/01/2018 09:50 AM »
Basic economics and the political realities of funding available for NASA mean that there's nothing suprising in the views Jim Bridenstine expressed, but still noteworthy that he said them and made only the briefest mention of SLS:

Quote
NASA head hints that reusable rocket cos. like SpaceX will enable Moon return

By Eric Ralph
Posted on August 30, 2018

In a series of thoroughly unexpected and impassioned introductory remarks at one of several 2018 Advisory Council meetings, NASA administrator Jim Bridenstine bucked at least two decades of norms by all but explicitly stating that reusable rockets built by innovative private companies like SpaceX and Blue Origin will enable the true future of space exploration.

https://www.teslarati.com/nasa-head-reusable-rockets-spacex-blue-origin-future/
I've not seen the new Administrator speak before.

He sounds pretty clear on what he wants to do and how he wants to do it.

It sounds like a pretty coherent policy (which is not something I'd expected from this President).

That said I'm not really sure this is really the place for a post on this subject. It does talk about commercial suppliers a bit but beyond reusable technology being a "good thing" I'm not sure it's that well focused on "views on reuse."
BFS. The worlds first Methane fueled FFORSC engined CFRP structured A380 sized aerospaceplane tail sitter capable of flying in Earth and Mars atmospheres. BFR. The worlds biggest Methane fueled FFORSC engined CFRP structured booster for BFS. First flight to Mars by end of 2022. Forward looking statements. T&C apply. Believe no one. Run your own numbers. So, you are going to Mars to start a better life? Picture it in your mind. Now say what it is out loud.

Offline marsbase

  • Member
  • Posts: 74
  • North Carolina
  • Liked: 45
  • Likes Given: 13
Re: SpaceX customers' views on reuse
« Reply #573 on: 09/01/2018 02:19 PM »
It sounds like a pretty coherent policy (which is not something I'd expected from this President).

That said I'm not really sure this is really the place for a post on this subject. It does talk about commercial suppliers a bit but beyond reusable technology being a "good thing" I'm not sure it's that well focused on "views on reuse."
Not such a coherent policy since he can't explain why he wants a Lunar "gateway"at all.  And even his reasons for going to the Moon at all are strange (Get water for Mars propellant?)

Since NASA is SpaceX's biggest customer and since these are the most direct comments from  NASA on reuse, I don't know how anything else is more relevant to this thread than his remarks.  The only customer that has been more supportive is Iridium.

Online oldAtlas_Eguy

  • Senior Member
  • *****
  • Posts: 3535
  • Florida
  • Liked: 1944
  • Likes Given: 237
Re: SpaceX customers' views on reuse
« Reply #574 on: 09/01/2018 05:38 PM »
The key to draw from NASA administrator Jim Bridenstine statements is that NASA at the top level is pro commercial LV reuse. Also that it is pro commercial. But both of these positions is not surprising coming from the new NASA administrator. He has expressed these views before he was the NASA administrator. He believes strongly that the future of access to space lies in the hands of commercial vendors like SpaceX and Blue Origin not in the hands of the government.

Offline dorkmo

  • Full Member
  • ****
  • Posts: 690
  • Liked: 318
  • Likes Given: 824
Re: SpaceX customers' views on reuse
« Reply #575 on: 09/02/2018 04:59 AM »
I think its insteresting to point out that bridenstine has a business degree instead of science, engineering, or law. Reuse makes perfect sense from a business perspective. Going to the moon might not make science sense, but at least we may do it on the cheap hah.

Offline speedevil

  • Senior Member
  • *****
  • Posts: 3191
  • Fife
  • Liked: 1631
  • Likes Given: 1958
Re: SpaceX customers' views on reuse
« Reply #576 on: 09/02/2018 10:18 AM »
I think its insteresting to point out that bridenstine has a business degree instead of science, engineering, or law. Reuse makes perfect sense from a business perspective. Going to the moon might not make science sense, but at least we may do it on the cheap hah.
Hah?
You absolutely do not want scientists driving your designs for going to the moon, in any more than the very loosest sense.
Spending 1% of your effective budget on improving launch, and 99% on optimising the hell out of what you're launching leads to horribly expensive payloads, where reusability doesn't make a meaningful difference.

TESS, for example, could have been launched 10-up on F9 for the same launch cost.
(It cost around twice the launcher cost, so is far from the worst offender).

Fully reusable launch with fuel transfer (even for FH, never mind BFR) can drop prices so far that customers have to redesign wholly, in order to make sensible use of the technology.

Going back to the moon 'The NASA way' is looking to be well north of $30B.
Even at $500/kg launch near-term for FH, that's 60000 tons in LEO, or >5000 tons on the lunar surface.

The mass disparity between that and perhaps 10, can't be overcome with really, really clever science.

You need business majors. (Or at least people closely paying attention to costs of everything and scoping the program for results, not what the scientific leadership might be want - PhDs in lightweight instrument design for example)

SpaceX customers need to be paying attention to the possibilities of reuse and dropping launch costs as part of their whole business case, and in some cases will need to wholly reengineer their designs for optimal performance, rather than just ticking the box to save on their launch cost.
« Last Edit: 09/02/2018 10:22 AM by speedevil »

Online kevinof

  • Full Member
  • ****
  • Posts: 682
  • Antibes
  • Liked: 492
  • Likes Given: 515
Re: SpaceX customers' views on reuse
« Reply #577 on: 09/02/2018 10:53 AM »
Happy to see an interest in both commercial and re-use at the top of Nasa. We need some different thinking, need a different approach to getting to the LEO/Moon/Mars. SLS is just Apollo Mark 2. It's a big expensive stack that we use and then dump in the ocean. It's multiple stages all to take a small(ish) capsule to where it needs to go.

We need to do things differently and that's why I'm really interested to see how BFS goes. Having the spacecraft integrated with the second stage is a novel approach, re-fueling after reaching orbit is different, re-using everything to make it much cheaper etc. Would like to see what Blue Origin with come up with and again I hope it's different thinking because we need different approaches on everything from launchers to tugs to landers if we're to afford both the initial cost and the ongoing costs.

Building another SLS in 20 years time won't cut it.

Online docmordrid

  • Senior Member
  • *****
  • Posts: 5109
  • Michigan
  • Liked: 2248
  • Likes Given: 1
Re: SpaceX customers' views on reuse
« Reply #578 on: 09/02/2018 12:09 PM »
I think its insteresting to point out that bridenstine has a business degree instead of science, engineering, or law.
>

Don't forget he was also a Navy carrier pilot (E-2C Hawkeye), and is a reserve officer in the Air National Guard
DM

Offline Lar

  • Fan boy at large
  • Global Moderator
  • Senior Member
  • *****
  • Posts: 10799
  • Saw Gemini live on TV
  • A large LEGO storage facility ... in Michigan
  • Liked: 7722
  • Likes Given: 5578
Re: SpaceX customers' views on reuse
« Reply #579 on: 09/02/2018 03:16 PM »
We have another thread analysing our new administrator and their qualifications and approach, so in depth analysis probably belongs there. But I think we may be seeing a sea change here at the top. Bridenstine is paying less lip service to SLS and ULA than Bolden did, I think. If NASA is allowed to truly embrace reuse for the bulk of what they do, even if saddled with SLS, that's significant.
"I think it would be great to be born on Earth and to die on Mars. Just hopefully not at the point of impact." -Elon Musk
"We're a little bit like the dog who caught the bus" - Musk after CRS-8 S1 successfully landed on ASDS OCISLY

Tags: