Author Topic: DARPA Experimental Spaceplane 1 (XS-1) Program  (Read 419611 times)

Offline jongoff

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #500 on: 04/25/2016 09:51 pm »
Jeff Foust –  ‏@jeff_foust

Melroy: decided to do a full and open competition for Phase 2 of XS-1 because we’re hoping to bring in some fresh ideas.

https://mobile.twitter.com/jeff_foust/status/724614984865558528

Which is kind of interesting in some regards. It suggests to me that either they're not confident any of the existing teams are capable of meeting all their goals, or that they've been lobbied by some outsiders who think they could be competitive (or something else entirely). Not sure which of the three.

~Jon

Offline Star One

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #501 on: 05/16/2016 04:09 pm »
Why DARPA is pursuing a reusable spaceplane

Quote
Tousley said DARPA would contribute “a healthy fraction” to the development of the spaceplane. XS-1 has been the agency’s top-funded space program the last two years. The White House asked for $50 million for the program in its budget request for fiscal year 2017.

Quote
“One of the critical parameters that’s coming out of the Phase 2 solicitation for XS-1 is the requirement that before we launch this asset for the first time, the vendors are going to prove to DARPA through a ground test of their propulsion system 10 times in 10 days,” he said. “We’re gojng to burn a lot of risk down”

http://spacenews.com/why-darpa-is-pursuing-a-reusable-spaceplane/

Offline strangequark

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Offline Star One

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #503 on: 05/26/2016 04:51 pm »
XS-1: Government’s Last Shot at Reusable Launch Vehicles

Quote
Sponable acknowledged that the funding DARPA has set aside for XS-1 won’t be enough to fully fund the winning vehicle’s development and flight tests. “It’s enough to pick someone and go. It’s probably not enough to fully fund what we have envisioned,” he said.

DARPA will make the XS-1 award using its Other Transaction Authority, which is more flexible than a traditional contract. “That implies cost share,” he said, with the winning company expected to contribute its own money to some degree to fully fund the vehicle’s development.

Quote
“We feel that a lot of these technologies, particularly the reusable ones, have come a long ways since we started the program a couple of years ago,” said Pamela Melroy, deputy director of DARPA’s Tactical Technology Office, during an April 25 presentation to the National Academies’ Aeronautics and Space Engineering Board. “So we’re throwing this to a full and open competition for phase two in the hope that we bring in some fresh ideas.”

Any new entrant, though, will be at a disadvantage to the three original companies, whose studies are roughly equivalent to a preliminary design review. “We are looking for a level of detail in the response that will make it very difficult for some people to come in off the fly and respond,” Sponable said.

Quote
Work on XS-1 has helped Masten’s workforce to more than double in the last year, but the company still has fewer than 40 employees, company founder Dave Masten said in a Space Access ’16 presentation. The company and its team of contractors were wrapping up work on their phase one contract and preparing for phase two. The company is also working to raise a $50 million financing round to support that effort, and plans to raise even more should it win the competition.

The company’s XS-1 design, like previous vehicles it has developed, takes off and lands vertically, although it has stubby wings to allow it to fly back to its launch site to make that vertical landing. “We don’t know what wheels, landing gear or runways are,” he quipped.

Quote
By contrast, XS-1 will use technologies further along in their development: at a technology readiness level of at least five, which on the one-to-nine TRL scale means at least some components of key technologies have been validated. Sponable said that earlier efforts often used technologies with TRLs of three or less.

But if DARPA fails with XS-1, it might not get another chance to work on an RLV program for years to come, and it’s unlikely anyone else in the federal government would, either. NASA is working on the heavy-lift, but expendable, Space Launch System. The Air Force is now focused on developing a new engine to replace the Atlas 5’s RD-180. Neither has any clear interest in, or funding for, RLVs.

http://www.spacenewsmag.com/feature/xs-1-the-governments-last-shot-at-reusable-launch-vehicles/
« Last Edit: 05/26/2016 04:59 pm by Star One »

Offline Archibald

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #504 on: 06/02/2016 03:55 pm »
I think that the XS-1, if it ever fly, should be used to try suborbital refueling. It would be ideal for the role - to settle for once if that (intriguing) idea is workable or not. 
Incidentally Michell Burnside Clapp works at DARPA (albeit on the cancelled ALASA program, and he is aparently to retire soon).
« Last Edit: 06/02/2016 03:57 pm by Archibald »
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Offline Chris Bergin

Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #505 on: 07/13/2016 04:27 pm »
Yay, we've done an article on this now :)

https://www.nasaspaceflight.com/2016/07/darpa-pushing-experimental-spaceplane-xs-1/

By Chris Gebhardt, with thanks to Derrick Stamos for being at the event to video Mr. Sponable's comments and grab slides, etc.
« Last Edit: 07/13/2016 06:26 pm by Chris Bergin »
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Offline Chris Bergin

Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #506 on: 07/13/2016 04:51 pm »
Oooh and Masten see the article and send us an updated render....added to the article.
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Offline Chalmer

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #507 on: 07/13/2016 07:16 pm »
The XS-1 program seems to have been completely overtaken by reality. Go 10 years back and I can see the usefulness of seeding a small, cheap and reusable rocket/spaceplane. But with the virtual explosion in small rocket companies, it just seem unnecessary. 

And with regards to lowering the cost of bigger DOD payloads, SpaceX is actually doing that as we speak. Blue Origin is on their way too. Both testing reusable systems. And I have a hard time seeing how XS-1 would have helped in this regard anyway.

Lastly, what is the justification for the 10 flights within 10 days? Seems like an arbitrary choice. What happens after those 10 days. Stand down for a year or some other unspecified time??

DARPA should spend the their money on something better.

Offline BrightLight

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #508 on: 07/13/2016 07:17 pm »
Yay, we've done an article on this now :)

https://www.nasaspaceflight.com/2016/07/darpa-pushing-experimental-spaceplane-xs-1/

By Chris Gebhardt, with thanks to Derrick Stamos for being at the event to video Mr. Sponable's comments and grab slides, etc.
Really nice article Chris - the metallic TPS - do you or anyone know if the idea is to use the TPS originally proposed for the X-33 and what TRL does DARPA expect from the TPS?

Offline BrightLight

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #509 on: 07/13/2016 07:21 pm »
It would be kind of fun to have the Pan Am logo on the fins of the spaceplane in the aerospace port picture :)

Offline whitelancer64

Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #510 on: 07/13/2016 08:01 pm »
The XS-1 program seems to have been completely overtaken by reality. Go 10 years back and I can see the usefulness of seeding a small, cheap and reusable rocket/spaceplane. But with the virtual explosion in small rocket companies, it just seem unnecessary. 

And with regards to lowering the cost of bigger DOD payloads, SpaceX is actually doing that as we speak. Blue Origin is on their way too. Both testing reusable systems. And I have a hard time seeing how XS-1 would have helped in this regard anyway.

Lastly, what is the justification for the 10 flights within 10 days? Seems like an arbitrary choice. What happens after those 10 days. Stand down for a year or some other unspecified time??

DARPA should spend the their money on something better.

There has been an increase in small-payload orbital rockets, but they still require several months to build, prep, and launch.

I'm guessing that 10 flights in 10 days goal isn't a realistic plan for regular operations, i.e. they will not be launching 365 times per year (not that that would be possible, considering weather, etc.). What they want is having the capability for daily turnarounds and a booster stage robust enough to fly 10+ times without major overhauls. With 10 times in 10 days being possible, say, for war time operations. Other than that it might just operate on weekly turn around basis, which would reduce the stresses on the launch vehicle and extend its operational life. The end result will be a "launch on demand" capability for small payloads, rather than having to plan years in advance to launch something.

This is a capability that does not yet exist, nor will it exist in the near future, even with small rockets like Firefly Alpha and Electron.
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Offline Rocket Science

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #511 on: 07/13/2016 08:02 pm »
Great article and visuals Chris G and Derrick. :) 10 flights in 10 days seem like someone has been reading from Elon's playbook. I see they are open to both horizontal or vertical landing. I still feel that horizontal landing is less stressful on the vehicle and requiring less refurbishment (hence my winged Flyback Falcon a few years back) I will still be happy if SpaceX proves me wrong. ;) Looks like more exciting times ahead for rocketry! 8)
« Last Edit: 07/13/2016 08:04 pm by Rocket Science »
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Offline john smith 19

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #512 on: 07/13/2016 09:07 pm »
Jeff Foust –  ‏@jeff_foust

Melroy: decided to do a full and open competition for Phase 2 of XS-1 because we’re hoping to bring in some fresh ideas.

https://mobile.twitter.com/jeff_foust/status/724614984865558528

Which is kind of interesting in some regards. It suggests to me that either they're not confident any of the existing teams are capable of meeting all their goals, or that they've been lobbied by some outsiders who think they could be competitive (or something else entirely). Not sure which of the three.

~Jon
Indeed.

The 2020 engine readiness requirement would make the use of a sub scale version of SABRE, from REL, difficult.
MCT ITS BFR SS. The worlds first Methane fueled FFSC engined CFRP SS structure A380 sized aerospaceplane tail sitter capable of Earth & Mars atmospheric flight.First flight to Mars by end of 2022 TBC. T&C apply. Trust nothing. Run your own #s "Extraordinary claims require extraordinary proof" R. Simberg."Competitve" means cheaper ¬cheap SCramjet proposed 1956. First +ve thrust 2004. US R&D spend to date > $10Bn. #deployed designs. Zero.

Offline john smith 19

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #513 on: 07/13/2016 09:08 pm »
Really nice article Chris - the metallic TPS - do you or anyone know if the idea is to use the TPS originally proposed for the X-33 and what TRL does DARPA expect from the TPS?
IIRC the LM X33 TPS was made by Rohr industries. One of the AIAA reports on it said they had come up with a preliminary improved design that was much lighter. Key features were scraping the capped tubes holding the mounting bolts in favor of some wire fasteners that can be locked in using a special hand tool.

After propulsion TPS is the big issue. Figures from the now defunct Shuttle TPSX database gave replacement costs of $12m/m^2 for tiels and $3m for blankets.

That suggests any design of vehicle and/or TPS must either a)Keep the amount of damaged TPS per flight to 1 m^2 or less or b)radically lower the cost of NDT/repair/replacement of TPS.

There are bright spots.

The mission is not a cruise mission and is not to full orbital velocity. Once the 2nd stage is deployed the vehicle can start slowing down immediately so the total integrated heat pulse can be relatively short. 

Grumman pitched what was essentially Autoclave Aerated Concrete for the Shuttle tiles. They are closed cell (and hence waterproof) and float in water, but they weren't the 95% air that the Lockheed stuff was. OTOH they did not need re-waterproofing, are available in huge quantities at low cost and can be machined to fairly close tolerances.

Work was done for Aluminum alloys for commercial supersonic transports. This resulted in powder metallurgy alloys with uses up to 450c. I'm not sure if they are commercially available, although I believe some Iron based PM alloys are planned for ESA lifting body reentry demonstrators.

This is relevant because historically the density of Ni based superalloys is so high TPS designs have been honeycomb panels with the skins slightly thicker than the interior honeycomb, making them very prone to damage.

Note that a TPS with good thermal conductivity sideways can conduct heat so efficiently it can keep the system below the materials melting point, which is what makes Aluminum rocket combustion chambers possible. An interesting riff on this was adding silicone to (IIRC) the oxidizer of the Agena stage to deposit a layer of Silica on the chamber walls. This could be adapted to a flame sprayed re-coating of any metallic TPS.

So a PM Aluminum front face, perhaps with some kind of clips between panels, with a stainless steel HC and back face, might be  viable.

One thing no seems to talk about. Ceramic nuts, bolts, washers, rods and tubes are available off the shelf. Yes they are relatively fragile but they excellent insulators and small enough that they should very good thermal shock resistance. With proper design I think a "snap fit" approach is possible.

I have yet to see a TPS design that acknowledges they even exist  :(
MCT ITS BFR SS. The worlds first Methane fueled FFSC engined CFRP SS structure A380 sized aerospaceplane tail sitter capable of Earth & Mars atmospheric flight.First flight to Mars by end of 2022 TBC. T&C apply. Trust nothing. Run your own #s "Extraordinary claims require extraordinary proof" R. Simberg."Competitve" means cheaper ¬cheap SCramjet proposed 1956. First +ve thrust 2004. US R&D spend to date > $10Bn. #deployed designs. Zero.

Offline john smith 19

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #514 on: 07/13/2016 09:23 pm »
10 flights in 10 days seem like someone has been reading from Elon's playbook.
You have that backward. Sponable was Project Manager for the DC-X project that demonstrated 2 flights in 26 hours for a M3 capable LH2 fueled vehicle 25 years ago.
Quote
I see they are open to both horizontal or vertical landing. I still feel that horizontal landing is less stressful on the vehicle and requiring less refurbishment (hence my winged Flyback Falcon a few years back)
Depends. A VTHL design gives you the worst of both worlds for stresses, needing a shape structure that's strong in 2 axes, one of which has to be phenomenally light to allow takeoff at all.
Quote
I will still be happy if SpaceX proves me wrong. ;) Looks like more exciting times ahead for rocketry! 8)
We're still waiting for the first 2nd launch of an F9 first stage.

The real question is how much will it lower the price of that launch by?
MCT ITS BFR SS. The worlds first Methane fueled FFSC engined CFRP SS structure A380 sized aerospaceplane tail sitter capable of Earth & Mars atmospheric flight.First flight to Mars by end of 2022 TBC. T&C apply. Trust nothing. Run your own #s "Extraordinary claims require extraordinary proof" R. Simberg."Competitve" means cheaper ¬cheap SCramjet proposed 1956. First +ve thrust 2004. US R&D spend to date > $10Bn. #deployed designs. Zero.

Offline Star One

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #515 on: 07/13/2016 09:29 pm »
The XS-1 program seems to have been completely overtaken by reality. Go 10 years back and I can see the usefulness of seeding a small, cheap and reusable rocket/spaceplane. But with the virtual explosion in small rocket companies, it just seem unnecessary. 

And with regards to lowering the cost of bigger DOD payloads, SpaceX is actually doing that as we speak. Blue Origin is on their way too. Both testing reusable systems. And I have a hard time seeing how XS-1 would have helped in this regard anyway.

Lastly, what is the justification for the 10 flights within 10 days? Seems like an arbitrary choice. What happens after those 10 days. Stand down for a year or some other unspecified time??

DARPA should spend the their money on something better.
I imagine a lot of those payloads will be classified ones. The DOD made it clear more than once that one way of achieving survivability in space is through more but cheaper and smaller payloads. Too small for conventional launchers and needing quicker reactions than normal launchers.

Offline Coastal Ron

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #516 on: 07/13/2016 09:43 pm »
Great NSF article.  However I'm still scratching my head over this DARPA effort.

Yes, reusable launch systems are good things to pursue, but it really does seem like they are ignoring current events.  For instance, wouldn't it make sense to focus on current technologies to see how far they can go?

I guess what bothers me is that DARPA is being overly specific about what they want, such as the 10 launches in 10 days, and to me fake requirements breed capabilities that don't match reality - which means the systems could end up being unsustainable (i.e. why not 5 in 10 days, or??).  Not unlike the Shuttle, which was supposedly designed for high reusability, yet there wasn't a need for it's full capabilities.

It just seems like DARPA has skipped too far ahead of this issue, and is missing out on surveying WHAT IS POSSIBLE using the technologies that have far less risk.  Especially since they point out that this effort has a TRL of 5, and the X-33 program, which was very challenging, had a TRL of 3.  Plus they don't have much money, which further muddies things.  I think their risk/reward ratio is not right.

As an example, what if instead of focusing on an SSTO that has a low payload capability, that they focused on using existing reusable stage technology, and added a reusable upper stage?  Which is essentially what Elon Musk had originally hoped he could do with the Falcon family, but I think they found such a capability was a lower priority than the various other efforts they were working.

Any who, still watching this with a curious eye...
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Offline Rocket Science

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Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #517 on: 07/13/2016 10:07 pm »
10 flights in 10 days seem like someone has been reading from Elon's playbook.
You have that backward. Sponable was Project Manager for the DC-X project that demonstrated 2 flights in 26 hours for a M3 capable LH2 fueled vehicle 25 years ago.
Quote
I see they are open to both horizontal or vertical landing. I still feel that horizontal landing is less stressful on the vehicle and requiring less refurbishment (hence my winged Flyback Falcon a few years back)
Depends. A VTHL design gives you the worst of both worlds for stresses, needing a shape structure that's strong in 2 axes, one of which has to be phenomenally light to allow takeoff at all.
Quote
I will still be happy if SpaceX proves me wrong. ;) Looks like more exciting times ahead for rocketry! 8)
We're still waiting for the first 2nd launch of an F9 first stage.

The real question is how much will it lower the price of that launch by?
The DC-X was a great demonstrator John, but it never flew it the flight regimes of a Falcon 9R S1. Of  course re-usabilty much less, economic re-usablity has to be proven, as I have been on record as saying. Shapes and structures are all compromises as we know.
I will still continue to cheer on you bird of choice SKYLON and look forward to her first flight. Like I said, exciting times! :)
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Offline whitelancer64

Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #518 on: 07/13/2016 10:22 pm »
Great NSF article.  However I'm still scratching my head over this DARPA effort.

Yes, reusable launch systems are good things to pursue, but it really does seem like they are ignoring current events.  For instance, wouldn't it make sense to focus on current technologies to see how far they can go?

I guess what bothers me is that DARPA is being overly specific about what they want, such as the 10 launches in 10 days, and to me fake requirements breed capabilities that don't match reality - which means the systems could end up being unsustainable (i.e. why not 5 in 10 days, or??).  Not unlike the Shuttle, which was supposedly designed for high reusability, yet there wasn't a need for it's full capabilities.

It just seems like DARPA has skipped too far ahead of this issue, and is missing out on surveying WHAT IS POSSIBLE using the technologies that have far less risk.  Especially since they point out that this effort has a TRL of 5, and the X-33 program, which was very challenging, had a TRL of 3.  Plus they don't have much money, which further muddies things.  I think their risk/reward ratio is not right.

As an example, what if instead of focusing on an SSTO that has a low payload capability, that they focused on using existing reusable stage technology, and added a reusable upper stage?  Which is essentially what Elon Musk had originally hoped he could do with the Falcon family, but I think they found such a capability was a lower priority than the various other efforts they were working.

Any who, still watching this with a curious eye...

DARPA's never focused on current technologies. It is always focused on the future, what's next, how to force iteration and innovation of current technologies to provide the capabilites they want to have, but nobody is providing or will likely provide soon.

DARPA, by its nature runs VERY high risk / high reward programs. Their projects often do not succeed... but when they do, they win big.

SX-1 is not an SSTO. It is a rapidly reusable first stage. Second stage reuse has a fundamental issue with weight for heat shielding and landing legs / gear / fuel cutting into payload capacity which means it is impractical for small to medium sized rockets.
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
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Offline whitelancer64

Re: DARPA Experimental Spaceplane 1 (XS-1) Program
« Reply #519 on: 07/13/2016 11:00 pm »
Great NSF article.  However I'm still scratching my head over this DARPA effort.
*snip
I guess what bothers me is that DARPA is being overly specific about what they want, such as the 10 launches in 10 days, and to me fake requirements breed capabilities that don't match reality
*snip

To expound: DARPA is a military think tank. 200 geniuses in an office building doing nothing but thinking of how to win the next big war. What capabilities are needed to respond to an enemy attack? Or what capability do we need to intercept that attack? Or prevent that attack from happening, or rendering the attack's effects inconsequential?

In this case, I think the scenario is an enemy taking out our orbital intelligence gathering or communications assets. An easy enough thing to do, really. Our military satellites are big, easily tracked, and expensive. And the response I think they think might be best seems to be quickly replacing those assets with a flock of smallsats. This requires having these smallsat assets designed, built, and stockpiled, along with a stockpile of second stages. But that's trivial. What we don't have, and what nobody has, is a booster rocket that can be rapidly deployed and launched on demand repeatedly and economically. I suspect that's the capacity DARPA wants.

Another benefit of this capacity is that even if we aren't attacked, we can retire our big, easily tracked, difficult to replace satellites and economically replace them with smallsats, where if a few get taken out, it's no big loss.
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

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