The X-37B: Exploring expanded capabilities for ISS missions

[manboy]

Orion is NASA's BLEO solution. ISS Commercial Crew solutions will be judged on the basis of ISS only, nothing more.

From the NASA perspective, maybe. SpaceX obviously has grandiose ambitions for Dragon, and I recall a Boeing engineer telling me CST was designed for lunar-class reentry velocities.

Well it's the same shape as the Apollo Command Module and uses the same material for its heatshield.

[phred]

CST was designed for lunar-class reentry velocities.

What kind of reentry velocities was X-37 designed for?

[Rocket Science]

Orion is NASA's BLEO solution. ISS Commercial Crew solutions will be judged on the basis of ISS only, nothing more.

From the NASA perspective, maybe. SpaceX obviously has grandiose ambitions for Dragon, and I recall a Boeing engineer telling me CST was designed for lunar-class reentry velocities. The fact that CST is capable of such future missions (and an X-37 based vehicle is not) may have impacted the capsule being chosen as Boeing's bid.

I  agree with you Simon as I felt that Boeing was hedging its bet with the choice of the CST-100 moldline...

[Patchouli]

Well it's the same shape as the Apollo Command Module and uses the same material for its heatshield.

I heard it's an all new material called BLA or Boeing light weight ablator probably similar to PICA.

If it is similar to PICA then it should be capable of lunar reentries with minor modifications.

Orion is NASA's BLEO solution. ISS Commercial Crew solutions will be judged on the basis of ISS only, nothing more.

From the NASA perspective, maybe. SpaceX obviously has grandiose ambitions for Dragon, and I recall a Boeing engineer telling me CST was designed for lunar-class reentry velocities. The fact that CST is capable of such future missions (and an X-37 based vehicle is not) may have impacted the capsule being chosen as Boeing's bid.

I remember reading lunar velocity reentries supposedly were one reason why SNC rejected the similar X-34 shape for their orbital vehicle.

With the X-34 shape temps on the TPS were just too close to the failure points to be comfortable.
Something within 200 to 400C of the failure point.
It sounds like a lot of margin but really it's a razor thin margin when you looking at temps of 3600C or more.

On the CST-100 I heard Boeing chose it because they could reuse much of the Apollo flight data.
You have good estimates of what to expect so not as much need for scale testing or to over engineer the TPS.

[Lars_J]

I have my doubts the X-37C would be a simple scale-up.  It would be unshrouded with a ~7.7m wingspan, and by my back-of-the-envelope scribbling it seems the weight ceiling (payload of an Atlas V 551/552, DIVH too expensive) might be a challenge too.   (1.7 ^3 = 4.91 x 5 mT X-37B loaded weight = 24.6 mT, plus pressurized space with life support system and pusher escape system.  Maybe that loaded weight included depleted uranium anvils to drop on DPRK,  though, and weight scaling isn't an issue.)

Yep, you are probably onto something here. The scale-up is not as trivial as some think.

[Robotbeat]

More capable? CST-100 seems much more capable of BLEO than X-37(x).

Which is completely irrelevant here when it comes to servicing the ISS.

not at all. A plan that has significant traction is to extend ISS to a Lagrange point, to facilitate BLEO exploration. That still has logistical needs.

Orion is NASA's BLEO solution. ISS Commercial Crew solutions will be judged on the basis of ISS only, nothing more.

Why?

EDIT:
That contradicts what is said here:
http://www.nasa.gov/offices/c3po/home/c3po_goal_objectives.html

Commercial Crew and Cargo Program Office (C3PO)
 
Program Goal

The C3PO will extend human presence in space by enabling an expanding and robust U.S. commercial space transportation industry.

Program Objectives

*Implement U.S. Space Exploration policy with investments to stimulate the commercial space industry

*Facilitate U.S. private industry demonstration of cargo and crew space transportation capabilities with the goal of achieving safe, reliable, cost effective access to low-Earth orbit

*Create a market environment in which commercial space transportation services are available to Government and private sector customers

Clearly, being usable for beyond-LEO is helpful for both the first and last bullet points.

[Lobo]

Orion is NASA's BLEO solution. ISS Commercial Crew solutions will be judged on the basis of ISS only, nothing more.

From the NASA perspective, maybe. SpaceX obviously has grandiose ambitions for Dragon, and I recall a Boeing engineer telling me CST was designed for lunar-class reentry velocities.

Well it's the same shape as the Apollo Command Module and uses the same material for its heatshield.

Isn't CST-100 based on Boeing's original proposal for Orion?  That lost out to LM's proposal? (Or I guess it would have been referred to as the "CEV" -Crew Exploration Vehicle, back then.  )
And LM later came out with an "Orion-Lite" concept based on the chosen Orion design, and was confused for awhile with CST-100 (perhaps before the name CST-100 was being commonly referred to as?).  But Orion Lite was based on LM's CEV proposal, where CST-100 was based on Boeing's CEV proposal.
If that's correct, it would seem by default to have the ability of lunar velocity reentries since it was based on a vehicle that was designed for that purpose.

[Lobo]

I have my doubts the X-37C would be a simple scale-up.  It would be unshrouded with a ~7.7m wingspan, and by my back-of-the-envelope scribbling it seems the weight ceiling (payload of an Atlas V 551/552, DIVH too expensive) might be a challenge too.   (1.7 ^3 = 4.91 x 5 mT X-37B loaded weight = 24.6 mT, plus pressurized space with life support system and pusher escape system.  Maybe that loaded weight included depleted uranium anvils to drop on DPRK,  though, and weight scaling isn't an issue.)

Yep, you are probably onto something here. The scale-up is not as trivial as some think.

Yea, I think the time for the X-37B to be used as a demonstrator for an X-37C “mini-shuttle” to be used to service the ISS was maybe way back during ESAS, if ESAS would have entertained such a vehicle for LEO service, while then developing the CEV for BLEO operation.  It still would have been somewhat redundant because the CEV was intended to be fully capable of servicing the ISS, as well as act as a cargo carrier with the CEV service module (per the ESAS report).  Still, it might not have been a bad backup to use in conjunction with the CEV/Orion and launching on a single stick Atlas variant.  Orion could also launch on an Atlas-552, just not with it’s full TEI propellant load in it’s service module, which it would need for a lunar mission, and thus NASA felt they needed to develop Ares 1 unfortunately.  (Of course, AVH would have been a far easier development program than Ares 1, and thus a single stick Atlas would be man-rated for launching Orion and X-37C to the ISS…but we’ll not go down that road here.  :-) )

As it sits now, as cool as the X-37B is, it’s just too small I think to really be of much use to the ISS.  I think it really is a demonstrator, rather than a useful vehicle unto itself.  Which means an X-37C would have to be developed.  But there is already a reusable space plane of similar size and capability that will launch on a man-rated Atlas if memory serves.  (what’s the name of that thing?....Dream-something I think… ;-)  )  And it’s already pretty far along, where X-37C would have to be started from scratch.

Plus, we are already running into the problem of too many LEO spacecraft for ISS servicing, not too few.  Which means lots of development costs and low flight rates.  There will be one, two , or even maybe three vehicles completely or near completely developed for Commercial Crew.  There are two for Commercial Cargo.  Plus there’s always Orion, which is the official ISS crew backup I think (I believe I read that somewhere) and really could launch to the ISS on an Atlas-552 as I mentioned before.  Like Apollo launching on Saturn 1B, it only needs a fraction of it’s 8mt service module main propellant capacity to go to the ISS.  Once Atlas is man-rated, it’ll be curious if NASA develops a payload adaptor to fit Orion, just in case.  Then they wouldn’t have to stack and roll out a whole Block 1 SLS if Orion needs to get to the ISS for some reason.  Just launch from where ever CST-100 or DC are launching from. 

[Lobo]

It would be more accurate to say that both NG/Boeing's CEV proposal and CST-100 are based on Boeing's OSP proposal.

Yea, I kinda forgot about how the CEV program was started.  (or more accurately, I wasn't following it much back then).  with lifting bodies as CEV's.  And then those contractor designes were thrown out, and NASA said they'd design the CEV as a big capsule, and then award a contract ot build their design. 

http://www.astronautix.com/craft/cev.htm

So I think CST-100 was based on some of that initial work done by Boeing before the actual contract to build Orion was awarded to LM?

Man...it just seems like things work SO much better/faster/cheaper when the contractor is just given performance requirements, and then comes up with their own design, rather than NASA designing it and telling a contractor to build it.  Nothing that hasn't been said 100 times around here...but you'd think someone would look back at history and figure that out.  :-)

[Lobo]

I have my doubts the X-37C would be a simple scale-up.  It would be unshrouded with a ~7.7m wingspan, and by my back-of-the-envelope scribbling it seems the weight ceiling (payload of an Atlas V 551/552, DIVH too expensive) might be a challenge too.   (1.7 ^3 = 4.91 x 5 mT X-37B loaded weight = 24.6 mT, plus pressurized space with life support system and pusher escape system.  Maybe that loaded weight included depleted uranium anvils to drop on DPRK,  though, and weight scaling isn't an issue.)

Yep, you are probably onto something here. The scale-up is not as trivial as some think.

On a bit of a hypothetical direction, how big could the X-37 geometry be made?  Could it be made (or have been made) into something the size of the STS orbiter?  Except with a hydrolox tank and J2 derivative engines on the back where the storable tanks are on the X-37B?  And then the orbiter would have been launched vertically on a booster rather than side mount.
Is the design scalable up that large?  Or is it only feasible in smaller sizes like the X-37B or C?

[Lobo]

I suspect you're still not comprehending.

Boeing's OSP proposal was a capsule. The name "OSP" itself was a misnomer; it wasn't limited to spaceplanes.

CST-100 is a younger sibling of NG/Boeing's CEV, not a child of it.

So, Boeing’s “Orbital Space Plane” was actually a capsule.  Umm….yea…I guess I didn’t comprehend that.  ;-)

But it makes sense, as I couldn’t pull up any images for an actual orbital space plane from Boeing for the CEV competition.  Only the one by LM.   It kept showing a capsule proposal from Boing for it’s “OSP” for the CEV competition.
And then references to X-40 and X-37 “Orbital Space Plane” for NASA’s “Space Launch Initiative” program.

Again, in this Astronautix page on the CEV, it looks like it shows a Boeing plane “OSP”, and a capsule “OSP”.

http://www.astronautix.com/craft/cev.htm

So I’m guessing that CST-100 was based on the ballistic capsule “OSP”?

But yea, I’ll be the first to admit I’m not well read up on all the history of that time.  But I’m learning more now.

[vt_hokie]

I suspect you're still not comprehending.

Boeing's OSP proposal was a capsule. The name "OSP" itself was a misnomer; it wasn't limited to spaceplanes.

CST-100 is a younger sibling of NG/Boeing's CEV, not a child of it.

So, Boeing’s “Orbital Space Plane” was actually a capsule.  Umm….yea…I guess I didn’t comprehend that.  ;-)

Well, at one point it was an X-37 based space plane design:

http://www.boeing.com/news/releases/2003/q2/nr_030418s.html

[Elmar Moelzer]

Yeah, IIRC, they had concepts for both.

[QuantumG]

"space plane" apparently means "reuse operations similar to an aircraft", and doesn't include the booster phase.. or so I've heard capsule pushers suggest.

If the booster phase is included, the term "gas-and-go" can be used, but probably won't be.

[Jim]

"space plane" apparently means "reuse operations similar to an aircraft", and doesn't include the booster phase.. or so I've heard capsule pushers suggest.

That wasn't the goal of OSP

[Elmar Moelzer]

That wasn't the goal of OSP

A lot of people, me included have wondered what the goals of the OSP really were... I thought it was not particularly "inspired" a program.

[Jim]

A lot of people, me included have wondered what the goals of the OSP really were... I thought it was not particularly "inspired" a program.

It wasn't a lot.

Same goal as Commercial Crew without the commercial part.

[Elmar Moelzer]

A lot of people, me included have wondered what the goals of the OSP really were... I thought it was not particularly "inspired" a program.

It wasn't a lot.

Same goal as Commercial Crew without the commercial part.

Yeah, only that the "commercial" part makes all the difference.

[Jim]

A lot of people, me included have wondered what the goals of the OSP really were... I thought it was not particularly "inspired" a program.

It wasn't a lot.

Same goal as Commercial Crew without the commercial part.

Yeah, only that the "commercial" part makes all the difference.

Nah, that is a minor part of it

[Elmar Moelzer]

A lot of people, me included have wondered what the goals of the OSP really were... I thought it was not particularly "inspired" a program.

It wasn't a lot.

Same goal as Commercial Crew without the commercial part.

Yeah, only that the "commercial" part makes all the difference.

Nah, that is a minor part of it

No, it isnt a "minor" part of it.