Author Topic: Refurbishment of Used Stages/Vehicles  (Read 212820 times)

Offline sdsds

  • Senior Member
  • *****
  • Posts: 5479
  • "With peace and hope for all mankind."
  • Seattle
  • Liked: 581
  • Likes Given: 677
Re: Refurbishment of Used Stages/Vehicles
« Reply #60 on: 01/02/2016 08:13 AM »
Quote
Falcon 9 back in the hangar at Cape Canaveral. No damage found, ready to fire again.

Isn't this news almost as significant as the landing itself?

Refurbishment cost is often cited as a reason why re-use may not be economic. This seems like a pretty significant datum point against that argument to me.

Agreed, though note well Musk said "fire again" not "fly again."
« Last Edit: 01/02/2016 08:13 AM by sdsds »
-- sdsds --

Offline rsdavis9

Re: Refurbishment of Used Stages/Vehicles
« Reply #61 on: 01/02/2016 12:48 PM »
So they are doing a static fire at lc39. Is it going to be a 2-4 sec static fire or is it going to be a full duration static fire ~3min. Can lc39 stand a full duration test fire? I know mcgregor can but can lc39 do it since it is designed for a 2-4 sec and then launch?
With ELV best efficiency was the paradigm. The new paradigm is reusable, good enough, and commonality of design.
Same engines. Design once. Same vehicle. Design once. Reusable. Build once.

Online pippin

  • Regular
  • Senior Member
  • *****
  • Posts: 2566
  • Liked: 292
  • Likes Given: 39
Re: Refurbishment of Used Stages/Vehicles
« Reply #62 on: 01/02/2016 01:09 PM »
Quote
Falcon 9 back in the hangar at Cape Canaveral. No damage found, ready to fire again.

Gosh, and here I thought we had an interesting thread going, and Mr Buzzkill Elon Musk tells us that no refurbishment may be necessary - other than soot removal and a fresh coat of paint.

He said nothing like that.
He said there is no damage, that doesn't mean stuff doesn't need to be replaced or cleaned (and I don't mean on the outside), you replace stuff for wear all the time in all kind of machinery (think of your car).
He also doesn't say that they haven't already done some of this.
And "ready to fire again" doesn't mean "ready to fly again". It doesn't even mean the whole thing is flightworthy. It doesn't mean the opposite either but don't interpret anything into Elon's words, he usually chooses them carefully in these things...
« Last Edit: 01/02/2016 01:10 PM by pippin »

Offline mheney

  • The Next Man on the Moon
  • Global Moderator
  • Full Member
  • *****
  • Posts: 779
  • Silver Spring, MD
  • Liked: 378
  • Likes Given: 200
Re: Refurbishment of Used Stages/Vehicles
« Reply #63 on: 01/02/2016 04:32 PM »
I don't think there's too much TOO read in Elon's words, here,  "Ready to fire" say to me that if you wanted to run
the stage through a Static fire exercise, you could, with the date as-is.

Shouldn't be surprising.  The center engine was fired 4 times during the launch and landing; two other engines were fired 3 times (I think - launch, boostback, and braking burns?)   Unless there was physical damage due to interaction with stuff on the ground (sand, grit, gators ...), there's no reason they couldn't just be fired up again - they're designed to be both reusable and restartable.

Of course, the proof is setting her up on the stand and actually relighting her ...

Offline Senex

  • Member
  • Posts: 44
  • Turtle Island
  • Liked: 75
  • Likes Given: 47
Re: Refurbishment of Used Stages/Vehicles
« Reply #64 on: 01/02/2016 07:03 PM »
While speculation is popular and is often justified by the absence of facts, there ARE some facts available. 

In an interesting article, space historian David Portree cites a study that looked at the refurbishment costs of the X-15 program that provides probably the most relevant real-world data we have:


"In November 1966, James Love and William Young, engineers at the NASA Flight Research Center at Edwards Air Force Base, completed a brief report in which they noted that the reusable suborbital booster for a reusable orbital spacecraft would undergo pressures, heating rates, and accelerations very similar to those the X-15 experienced."

"The average X-15 refurbishment time was 30 days, a period which had, they noted, hardly changed in four years. Even with identifiable improvements, they doubted that an X-15 could be refurbished in fewer than 20 days.

"At the same time, Love and Young argued that the X-15 program had demonstrated the benefits of reusability. They estimated that refurbishing an X-15 in 1964 had cost about $270,000 per mission.

"Love and Young cited North American Aviation estimates when they placed the cost of a new X-15 at about $9 million. They then calculated that 27 missions using expendable X-15s would have cost a total of $243 million. This meant, they wrote, that the cost of the reusable X-15 program in 1964 had amounted to just 3% of the cost of building 27 X-15s and throwing each one away after a single flight.

My bold.


http://www.wired.com/2013/05/the-x-15-rocket-plane-reusable-space-shuttle-boosters-1966/

Offline sanman

  • Senior Member
  • *****
  • Posts: 4487
  • Liked: 682
  • Likes Given: 8
Re: Refurbishment of Used Stages/Vehicles
« Reply #65 on: 01/02/2016 09:22 PM »
Anybody know what the theoretical or static-tested value is for the number of times the engines can be re-fired? Surely this must have been measured through rigorous ground testing.

Offline the_other_Doug

  • Senior Member
  • *****
  • Posts: 2726
  • Minneapolis, MN
  • Liked: 1786
  • Likes Given: 3387
Re: Refurbishment of Used Stages/Vehicles
« Reply #66 on: 01/03/2016 01:12 AM »
Anybody know what the theoretical or static-tested value is for the number of times the engines can be re-fired? Surely this must have been measured through rigorous ground testing.

I don't know if they have tested any of the engines to destruction, so it's hard to say.  I recall Ms. Shotwell noting at one point, a good year ago, that they were figuring on being able to fly each stage at least 10 times, but that their then-current testing indicated that the actual number of re-flights might become open-ended.  The phrase "maybe 40 or 50, maybe more" sticks in my head.

I won't be surprised if the actual number is a lot less than 40 or 50.  But I don't think anything official has been stated in terms of expected number of re-uses, and that SpaceX seems to think that 10 re-flights is a good number to toss out, but might be really conservative.
-Doug  (With my shield, not yet upon it)

Offline Torbjorn Larsson, OM

  • Full Member
  • **
  • Posts: 258
  • Liked: 71
  • Likes Given: 56
Re: Refurbishment of Used Stages/Vehicles
« Reply #67 on: 01/03/2016 03:36 AM »
Shouldn't be surprising.  The center engine was fired 4 times during the launch and landing; two other engines were fired 3 times (I think - launch, boostback, and braking burns?)   Unless there was physical damage due to interaction with stuff on the ground (sand, grit, gators ...), there's no reason they couldn't just be fired up again - they're designed to be both reusable and restartable.

Would they do it that way, wouldn't that tend to make them unnecessarily swap engine positions later? Wouldn't it be cheaper to apply a sequential even spread choice (with the possible exception of the center engine for the final single engine burn), as even as the octagon allows? I guess I am asking for photo evidence or other information on engine use.

Offline BruceM

  • Member
  • Posts: 35
  • Florida
  • Liked: 28
  • Likes Given: 40
Re: Refurbishment of Used Stages/Vehicles
« Reply #68 on: 01/03/2016 04:06 AM »
Quote
Falcon 9 back in the hangar at Cape Canaveral. No damage found, ready to fire again.

Isn't this news almost as significant as the landing itself?


They used to say trying to land a rocket doesn't make sense.  It is too (difficult, costly, inefficient, other - insert preferred explanation here ____________ ).

But Elon landed the rocket.

They used to say even if it could be landed it probably would be too (difficult, costly, inefficient, other -- insert preferred explanation here ____________ ) to reuse the rocket.

But Elon said, "No damage found, ready to fire again." While I'm not quite certain what this will actually mean in terms of turnaround (very interesting to hear all your thoughts on this), it does seem certain we've taken two very big steps.

Yes, there's still a lot to do.  But we've come light years.  Charles Krauthammer said, "Our trajectory in space... no longer will hinge on the whims of only tangentially interested politicians.  Space has now entered the era of the Teslas, the Edisons and the Wright brothers." (Thank you Eric Hedman).

It has been said before in this forum, "I wouldn't bet against Mr. Musk."  I wouldn't either.  The future is coming fast and all the tomorrows of space flight just got a whole lot closer.

What a great time to be alive!

What a great time to be a space enthusiast! (Thank you Chris & NASASpaceFLight).

What a great time to be part of this searching, struggling, strapping species called humans!

Bring it on!!!


Offline macpacheco

  • Full Member
  • ****
  • Posts: 861
  • Vitoria-ES-Brazil
  • Liked: 346
  • Likes Given: 2681
Re: Refurbishment of Used Stages/Vehicles
« Reply #69 on: 01/03/2016 05:46 AM »
While speculation is popular and is often justified by the absence of facts, there ARE some facts available. 

In an interesting article, space historian David Portree cites a study that looked at the refurbishment costs of the X-15 program that provides probably the most relevant real-world data we have:


"In November 1966, James Love and William Young, engineers at the NASA Flight Research Center at Edwards Air Force Base, completed a brief report in which they noted that the reusable suborbital booster for a reusable orbital spacecraft would undergo pressures, heating rates, and accelerations very similar to those the X-15 experienced."

"The average X-15 refurbishment time was 30 days, a period which had, they noted, hardly changed in four years. Even with identifiable improvements, they doubted that an X-15 could be refurbished in fewer than 20 days.

"At the same time, Love and Young argued that the X-15 program had demonstrated the benefits of reusability. They estimated that refurbishing an X-15 in 1964 had cost about $270,000 per mission.

"Love and Young cited North American Aviation estimates when they placed the cost of a new X-15 at about $9 million. They then calculated that 27 missions using expendable X-15s would have cost a total of $243 million. This meant, they wrote, that the cost of the reusable X-15 program in 1964 had amounted to just 3% of the cost of building 27 X-15s and throwing each one away after a single flight.

My bold.


http://www.wired.com/2013/05/the-x-15-rocket-plane-reusable-space-shuttle-boosters-1966/

That means almost nothing for F9R reuse.
X-15 was an experimental aircraft with 50 yr old tech.
X-15 used outdated rockets, used wings, outdated structural materials, and was a government driven program.
The Shuttle used far more up to date technology, but the need to do orbital re-entry with all of those thermal tiles. And there are many other big problems.
SpaceX has designed this first stage to be reusable. With the state of the art materials (that aren't uber expensive).
I suggest reviewing discussion pre F9R first flight that Musk demanded massive margins (for a single flight) precisely in order to make reuse possible.
« Last Edit: 01/03/2016 07:30 AM by macpacheco »
Looking for companies doing great things for much more than money

Offline JamesH

  • Full Member
  • ****
  • Posts: 525
  • United Kingdom
  • Liked: 283
  • Likes Given: 7
Re: Refurbishment of Used Stages/Vehicles
« Reply #70 on: 01/03/2016 10:09 AM »
While speculation is popular and is often justified by the absence of facts, there ARE some facts available. 

In an interesting article, space historian David Portree cites a study that looked at the refurbishment costs of the X-15 program that provides probably the most relevant real-world data we have:


"In November 1966, James Love and William Young, engineers at the NASA Flight Research Center at Edwards Air Force Base, completed a brief report in which they noted that the reusable suborbital booster for a reusable orbital spacecraft would undergo pressures, heating rates, and accelerations very similar to those the X-15 experienced."

"The average X-15 refurbishment time was 30 days, a period which had, they noted, hardly changed in four years. Even with identifiable improvements, they doubted that an X-15 could be refurbished in fewer than 20 days.

"At the same time, Love and Young argued that the X-15 program had demonstrated the benefits of reusability. They estimated that refurbishing an X-15 in 1964 had cost about $270,000 per mission.

"Love and Young cited North American Aviation estimates when they placed the cost of a new X-15 at about $9 million. They then calculated that 27 missions using expendable X-15s would have cost a total of $243 million. This meant, they wrote, that the cost of the reusable X-15 program in 1964 had amounted to just 3% of the cost of building 27 X-15s and throwing each one away after a single flight.

My bold.


http://www.wired.com/2013/05/the-x-15-rocket-plane-reusable-space-shuttle-boosters-1966/

That means almost nothing for F9R reuse.
X-15 was an experimental aircraft with 50 yr old tech.
X-15 used outdated rockets, used wings, outdated structural materials, and was a government driven program.
The Shuttle used far more up to date technology, but the need to do orbital re-entry with all of those thermal tiles. And there are many other big problems.
SpaceX has designed this first stage to be reusable. With the state of the art materials (that aren't uber expensive).
I suggest reviewing discussion pre F9R first flight that Musk demanded massive margins (for a single flight) precisely in order to make reuse possible.

Nothing? Surely it gives an approximate baseline? They doubt it could be refurbed in 20 days. F9R should be less than that for exactly the reasons you specify.

Offline macpacheco

  • Full Member
  • ****
  • Posts: 861
  • Vitoria-ES-Brazil
  • Liked: 346
  • Likes Given: 2681
Re: Refurbishment of Used Stages/Vehicles
« Reply #71 on: 01/03/2016 10:36 AM »
That means almost nothing for F9R reuse.
X-15 was an experimental aircraft with 50 yr old tech.
X-15 used outdated rockets, used wings, outdated structural materials, and was a government driven program.
The Shuttle used far more up to date technology, but the need to do orbital re-entry with all of those thermal tiles. And there are many other big problems.
SpaceX has designed this first stage to be reusable. With the state of the art materials (that aren't uber expensive).
I suggest reviewing discussion pre F9R first flight that Musk demanded massive margins (for a single flight) precisely in order to make reuse possible.

Nothing? Surely it gives an approximate baseline? They doubt it could be refurbed in 20 days. F9R should be less than that for exactly the reasons you specify.

You assume F9R will require frequent refurbishment. I assume SpaceX know what its doing, and that recovered stages will refly quite a few times.
If a stage can be launched safely for at least 10 times, I think there will be no refurb. The parts that are still good will be saved and the skin will become recycled metal.
Parts might be swapped, but that's not refurb.
A fleet of 20 stages flying 10 times = 300 launches. Let's not forget that.
That's enough even to launch the entire SpaceX earth internet constellation a few times over.

Edit/Lar: Fixed quotes
« Last Edit: 01/03/2016 02:07 PM by Lar »
Looking for companies doing great things for much more than money

Online pippin

  • Regular
  • Senior Member
  • *****
  • Posts: 2566
  • Liked: 292
  • Likes Given: 39
Re: Refurbishment of Used Stages/Vehicles
« Reply #72 on: 01/03/2016 02:25 PM »
While speculation is popular and is often justified by the absence of facts, there ARE some facts available. 

In an interesting article, space historian David Portree cites a study that looked at the refurbishment costs of the X-15 program that provides probably the most relevant real-world data we have:


"In November 1966, James Love and William Young, engineers at the NASA Flight Research Center at Edwards Air Force Base, completed a brief report in which they noted that the reusable suborbital booster for a reusable orbital spacecraft would undergo pressures, heating rates, and accelerations very similar to those the X-15 experienced."

"The average X-15 refurbishment time was 30 days, a period which had, they noted, hardly changed in four years. Even with identifiable improvements, they doubted that an X-15 could be refurbished in fewer than 20 days.

"At the same time, Love and Young argued that the X-15 program had demonstrated the benefits of reusability. They estimated that refurbishing an X-15 in 1964 had cost about $270,000 per mission.

"Love and Young cited North American Aviation estimates when they placed the cost of a new X-15 at about $9 million. They then calculated that 27 missions using expendable X-15s would have cost a total of $243 million. This meant, they wrote, that the cost of the reusable X-15 program in 1964 had amounted to just 3% of the cost of building 27 X-15s and throwing each one away after a single flight.

My bold.


http://www.wired.com/2013/05/the-x-15-rocket-plane-reusable-space-shuttle-boosters-1966/

That means almost nothing for F9R reuse.
X-15 was an experimental aircraft with 50 yr old tech.
X-15 used outdated rockets, used wings, outdated structural materials, and was a government driven program.
The Shuttle used far more up to date technology, but the need to do orbital re-entry with all of those thermal tiles. And there are many other big problems.
SpaceX has designed this first stage to be reusable. With the state of the art materials (that aren't uber expensive).
I suggest reviewing discussion pre F9R first flight that Musk demanded massive margins (for a single flight) precisely in order to make reuse possible.

Nothing? Surely it gives an approximate baseline? They doubt it could be refurbed in 20 days. F9R should be less than that for exactly the reasons you specify.

No it doesn't at all. It just looks at the vehicle cost comparing the cost of a new vehicle to the refurbishment costs.
It completely leaves out the mission cost with things like pilots, facilities, a B 52,...
Unless you know the number for these you know the overall amount of $$$ saved but not whether that amounts to 10%, 50% or 75% or whatever of the program cost. The one thing you do know by looking at the figures is that there 3% are nonsense
« Last Edit: 01/03/2016 02:25 PM by pippin »

Offline Senex

  • Member
  • Posts: 44
  • Turtle Island
  • Liked: 75
  • Likes Given: 47
Re: Refurbishment of Used Stages/Vehicles
« Reply #73 on: 01/03/2016 06:12 PM »

That means almost nothing for F9R reuse.
X-15 was an experimental aircraft with 50 yr old tech.
X-15 used outdated rockets, used wings, outdated structural materials, and was a government driven program.
The Shuttle used far more up to date technology, but the need to do orbital re-entry with all of those thermal tiles. And there are many other big problems.
SpaceX has designed this first stage to be reusable. With the state of the art materials (that aren't uber expensive).
I suggest reviewing discussion pre F9R first flight that Musk demanded massive margins (for a single flight) precisely in order to make reuse possible.

I totally agree — that was my point as well. 

I had cross-posted the reference to Portree's article over on 

SpaceX General Section / Re: SpaceX long-term stage processing goal = 48 hour turnaround

as well, and added:

At least two implications can be deduced from this reference:

1. There has been much talk on the forums about the effects of "fatigue" with images of much of the booster requiring rework or even replacement.  Three X-15's flew 199 flights — and average of 66 each.  Just because a Falcon 9 flies high and fast does not mean it will be structurally degraded after a few cycles.

2. The X-15 required weeks of refurbishment.  It is safe to assume that most of that related to mechanical equipment.  That was with technology that had literally just been invented.  In a vehicle designed from the beginning with operating economies in mind, using a relatively mature technology, this might be dramatically lower.

I think so much of the reuse concerns have been overstated.  So, again, I agree with you.

Online Lars-J

  • Senior Member
  • *****
  • Posts: 4428
  • California
  • Liked: 3964
  • Likes Given: 2398
Re: Refurbishment of Used Stages/Vehicles
« Reply #74 on: 01/03/2016 06:31 PM »

Shouldn't be surprising.  The center engine was fired 4 times during the launch and landing; two other engines were fired 3 times (I think - launch, boostback, and braking burns?)   Unless there was physical damage due to interaction with stuff on the ground (sand, grit, gators ...), there's no reason they couldn't just be fired up again - they're designed to be both reusable and restartable.

Would they do it that way, wouldn't that tend to make them unnecessarily swap engine positions later? Wouldn't it be cheaper to apply a sequential even spread choice (with the possible exception of the center engine for the final single engine burn), as even as the octagon allows? I guess I am asking for photo evidence or other information on engine use.

The center engine is used in all burns. And as far as why you would use the same other two engines for multiple burns - we don't know - but it has been assumed, since when each engine has a its own supply of ignition fluids (TEA/TEB) it makes more sense to just give 3 engines more of it instead of giving all engines the same restart capability. (It is nasty dangerous stuff) But I could be wrong on the last point.

Offline guckyfan

  • Senior Member
  • *****
  • Posts: 6791
  • Germany
  • Liked: 1809
  • Likes Given: 1842
Re: Refurbishment of Used Stages/Vehicles
« Reply #75 on: 01/03/2016 07:24 PM »
The center engine is used in all burns. And as far as why you would use the same other two engines for multiple burns - we don't know - but it has been assumed, since when each engine has a its own supply of ignition fluids (TEA/TEB) it makes more sense to just give 3 engines more of it instead of giving all engines the same restart capability. (It is nasty dangerous stuff) But I could be wrong on the last point.

I am assuming something else. All engines are ground started from an external supply. So why would they not be air started by a common supply? It would be a pure software command, which engine restarts. That would make it possible to use the outer engines in turn. Only the center engine would need to be replaced/refurbished sooner. Unless there are other reasons in the geometry of the stage to always use the same engines.

Offline sanman

  • Senior Member
  • *****
  • Posts: 4487
  • Liked: 682
  • Likes Given: 8
Re: Refurbishment of Used Stages/Vehicles
« Reply #76 on: 01/03/2016 09:07 PM »
The center engine is used in all burns. And as far as why you would use the same other two engines for multiple burns - we don't know - but it has been assumed, since when each engine has a its own supply of ignition fluids (TEA/TEB) it makes more sense to just give 3 engines more of it instead of giving all engines the same restart capability. (It is nasty dangerous stuff) But I could be wrong on the last point.

So on the one hand there's the idea that across multiple reflights, you keep the same engines in the same spots, using them in exactly the same way again and again. This means that the 3 engines used for multiple burns within a flight are a bit more suped up - particularly that central engine that gets used for landing.

Then on the other hand, there's the idea that you "rotate the tires" across multiple reflights - swapping the less used engines in place of the more used ones, so that they all get their fair share of wear and tear.

Which way is the better way out of those 2 approaches - and why? Are there any other approaches that might be better still? Why?
« Last Edit: 01/03/2016 09:09 PM by sanman »

Offline Coastal Ron

  • Senior Member
  • *****
  • Posts: 4311
  • I live... along the coast
  • Liked: 2940
  • Likes Given: 3879
Re: Refurbishment of Used Stages/Vehicles
« Reply #77 on: 01/03/2016 09:23 PM »
So on the one hand there's the idea that across multiple reflights, you keep the same engines in the same spots, using them in exactly the same way again and again. This means that the 3 engines used for multiple burns within a flight are a bit more suped up - particularly that central engine that gets used for landing.

Then on the other hand, there's the idea that you "rotate the tires" across multiple reflights - swapping the less used engines in place of the more used ones, so that they all get their fair share of wear and tear.

Which way is the better way out of those 2 approaches - and why? Are there any other approaches that might be better still? Why?

Early on SpaceX may be taking engines off at a much higher rate to validate empirically how they're doing, so let's ignore that for right now.

Once they have validated engine reliability, I'm not familiar with how airlines handle this but I would imagine that you would not remove an engine unless there is a reason you don't want it to fly on the next flight.

Over time you're going to end up with a mix of used engines, including the potential for some to be flown on new stages, so "rotating" them is not going to add much value, especially the eight outboard engines.

My $0.02
If we don't continuously lower the cost to access space, how are we ever going to afford to expand humanity out into space?

Offline HIP2BSQRE

  • Regular
  • Full Member
  • ****
  • Posts: 661
  • Liked: 41
  • Likes Given: 14
Re: Refurbishment of Used Stages/Vehicles
« Reply #78 on: 01/03/2016 09:26 PM »
Anybody know what the theoretical or static-tested value is for the number of times the engines can be re-fired? Surely this must have been measured through rigorous ground testing.

I don't know if they have tested any of the engines to destruction, so it's hard to say.  I recall Ms. Shotwell noting at one point, a good year ago, that they were figuring on being able to fly each stage at least 10 times, but that their then-current testing indicated that the actual number of re-flights might become open-ended.  The phrase "maybe 40 or 50, maybe more" sticks in my head.

I won't be surprised if the actual number is a lot less than 40 or 50.  But I don't think anything official has been stated in terms of expected number of re-uses, and that SpaceX seems to think that 10 re-flights is a good number to toss out, but might be really conservative.

Here is the quote " “If you are able to refly your first stage, you need to establish how many times can you refly it -- is it 20 times, 40 times, 50 times?”  SpaceX does not know.    http://www.bloomberg.com/news/articles/2015-04-13/spacex-plans-to-try-again-to-land-rocket-booster-on-barge-at-sea

Offline guckyfan

  • Senior Member
  • *****
  • Posts: 6791
  • Germany
  • Liked: 1809
  • Likes Given: 1842
Re: Refurbishment of Used Stages/Vehicles
« Reply #79 on: 01/03/2016 09:49 PM »
Here is the quote " “If you are able to refly your first stage, you need to establish how many times can you refly it -- is it 20 times, 40 times, 50 times?”  SpaceX does not know.    http://www.bloomberg.com/news/articles/2015-04-13/spacex-plans-to-try-again-to-land-rocket-booster-on-barge-at-sea

That's for the airframe. They were and probably are not yet sure how many reflights they can do with that. But there is the statement of Elon Musk about the engines. 40 cycles, which was assumed to be ignitions between refurbishments. But the engines have no meaningful limit of use. After 40 cycles some highly stressed components need to be replaced.

Tags: