X-37B crew launcher

[Jim]

Bump

[Lee Jay]

Bump

What?  Is something happening here?

[mlorrey]

Bump

What?  Is something happening here?

No, Jim just wants to promote the fact that he thinks he won an argument.

[Jason1701]

This is an old and tired subject
NASA did consider for OSP and it lost to the capsule design.  Wing vehicles do not have passive abort and entry capabilities

If it was an "old and tired subject" three years ago, I wonder what it classifies as now.

[Silmfeanor]

This is an old and tired subject
NASA did consider for OSP and it lost to the capsule design.  Wing vehicles do not have passive abort and entry capabilities

If it was an "old and tired subject" three years ago, I wonder what it classifies as now.

It still is!
It would need LAS, have it's size, structure and systems dramatically changed. You'd need a whole new lifting-body spacecraft, instead of prodding on with the X-37b.

( and it's name is dream chaser and that is not the same as the X-37 )

Rockets are not legos...

[go4mars]

Is X37b for delivering munitions? 

[grakenverb]

Was this the reason for the "bump"?

http://www.aviationweek.com/aw/generic/story_channel.jsp?channel=defense&id=news/awst/2011/10/10/AW_10_10_2011_p47-378479.xml&headline=X-37B%20Vehicle%20Derivative%20Plan%20Revealed

[Kharkov]

Is X37b for delivering munitions? 

The X-37B? No.

I'd say the X-37B is a prototype for an eventual weapons platform which will be quite similar to (and bigger than) the X-37.

The US Airforce/DOD is probably envisioning a fleet (not more than 20, I'd say) of them in inclined orbits & retrograde equatorial & polar orbits, capable of launching a small interceptor missile (or missiles) to take out selected 'enemy' satellites.

Once they run out of ammo, they can re-enter the Earth's atmosphere, using their cross-range capability to speedily return to an airbase for rearming & return to a launch site.

[douglas100]

That makes no sense to me. You don't need a spaceplane to launch an ASAT weapon. You certainly don't need a "fleet" of them. Operationally it makes much more sense to keep your weapons on the ground, (whether direct impact weapons or perhaps directed-energy weapons) and out of harms way and launch them only as required.

[Ben the Space Brit]

I've long thought that the X-37 is the aerodynamic and hardware prototype for a re-usable quick-reaction vehicle of some sort.  What it is supposed to react quickly to and its mission is unknown but, given the difficulties of orbital mechanics, ASAT or orbital attack is unlikely; a ballistic missile would carry out both these missions better.

The only reason why X-37 could be the prototype of a weapons platform would be if there is a tacit understanding between the superpowers that land- and submarine-based ballistic missiles will only carry nuclear warheads for ease of international threat identification.  In such a scenario, some kind of mid-duration robot delivery vehicle that stays on the ground until needed and is then launched into an orbit overflying its target is one possible solution for sub-nuclear QR attack.

[Kharkov]

Do you need a spaceplane to launch an ASAT weapon? No.

Is there a benefit to launching from one? Yes.

Imagine a scenario. The US decides to destroy the satellites belonging to... let's say Russia or China. Launching ASAT weapons from the ground means a fairly significant time between launch & arrival on target. Even worse, you can only target part of the enemy's satellite fleet. Part of it will be too far away - you'll need to wait until orbital mechanics bring them closer, into reach. Even if that wasn't an issue, the time lag between launch & arrival on target would be so long that the target would have time to manoeuvre away.

Even worse, a launch from the ground would be detected by an enemy's early-warning system - the thermal bloom when the rocket launches.

On the other hand, if you launch from a small, winged weapons platform in orbit, you could have all your platforms firing, targeting all the enemy's satellites at once. The travel time would be greatly reduced & the chance of the launch not being noticed (or not being noticed in time to do anything about it) would be increased. The complete removal of the enemy's satellites would cause chaos for the enemy.

This, incidentally, is why I strongly disapprove of the X-37 program. It doesn't advance space technology as anything it learns will be classified & buried. I suspect that one of the reasons that American aerospace companies aren't trying to develop an SSTO (without being instructed/paid to by NASA) is the fear that, halfway down the road, they'll be informed by the Air Force/DOD that they're impinging on classified X-37 technology.

Even worse, such weapons would be very destabilising and so would hamper civilian access to orbit & the civilian development of space.

[Jim]

Is X37b for delivering munitions? 

The X-37B? No.

I'd say the X-37B is a prototype for an eventual weapons platform which will be quite similar to (and bigger than) the X-37.

The US Airforce/DOD is probably envisioning a fleet (not more than 20, I'd say) of them in inclined orbits & retrograde equatorial & polar orbits, capable of launching a small interceptor missile (or missiles) to take out selected 'enemy' satellites.

Once they run out of ammo, they can re-enter the Earth's atmosphere, using their cross-range capability to speedily return to an airbase for rearming & return to a launch site.

It is nothing of the sort.

It isn't a prototype.  It is an "X" vehicle, which is a test vehicle.

[aquanaut99]

Even worse, such weapons would be very destabilising and so would hamper civilian access to orbit & the civilian development of space.

And finally, the last thing we need is armed space assets shooting at other space assets in LEO. We already have a huge space debris problem there. After a few rounds of satellite-killing, we would almost certainly get a runaway Kessler syndrome, making LEO unusable for anything and anyone for decades to come.

[Jim]

Is there a benefit to launching from one? Yes.

Imagine a scenario. The US decides to destroy the satellites belonging to... let's say Russia or China. Launching ASAT weapons from the ground means a fairly significant time between launch & arrival on target. Even worse, you can only target part of the enemy's satellite fleet. Part of it will be too far away - you'll need to wait until orbital mechanics bring them closer, into reach. Even if that wasn't an issue, the time lag between launch & arrival on target would be so long that the target would have time to manoeuvre away.

Even worse, a launch from the ground would be detected by an enemy's early-warning system - the thermal bloom when the rocket launches.

On the other hand, if you launch from a small, winged weapons platform in orbit, you could have all your platforms firing, targeting all the enemy's satellites at once. The travel time would be greatly reduced & the chance of the launch not being noticed (or not being noticed in time to do anything about it) would be increased. The complete removal of the enemy's satellites would cause chaos for the enemy.

Wrong in so many different ways.
There is no benefit and it is just as detectable.

Having the platform on orbit means it is less able to hit targets and slower reaction time.  The only viable method for an ASAT on orbit, is the coorbital type, where the ASAT in the same orbit as the target.
Direct ascent ASATs such as the MHV or the SM3 use lower velocities than orbital, can hit multiple inclinations, have quicker response and reaction times.

It takes a lot more energy to do a direct ascent type intercept from orbit, since the orbital energy would be working against it. 

You really don't understand orbital mechanics.

[Jim]

1.  This, incidentally, is why I strongly disapprove of the X-37 program. It doesn't advance space technology as anything it learns will be classified & buried.

2.  I suspect that one of the reasons that American aerospace companies aren't trying to develop an SSTO (without being instructed/paid to by NASA) is the fear that, halfway down the road, they'll be informed by the Air Force/DOD that they're impinging on classified X-37 technology.

That is not a legitimate reason and also wrong.

1.  It isn't any different than what the DOD/NRO have done in the past.  They have always secretly tested space technology, which has remained classified.

2.  Huh?  That is just plain nonsense.  There is no such connection.  The X-37 is not being tested, what is carries is being tested.  The X-37 is a spacecraft and not a launch vehicle.  It has nothing to do with SSTO.  It requires a launch vehicle to put it in orbit. Data from X-37 operations such as entry is available.   

[Jim]

Launching ASAT weapons from the ground means a fairly significant time between launch & arrival on target.

no, it is less than 10 minutes.  Current ASATs are only for LEO.  There are no ASATs for GPS or GSO orbits. Anyway, a co orbital or "orbital direct ascent" would take hours.

[Kharkov]

Wow, Jim had a lot to say...

Ok, yes, you're right - the X-37 IS a test vehicle & not intended to be a weapon itself. The upcoming X-37C (bigger) will not be a weapon either. I'm still of the opinion that it is intended to pave the way for a small orbital weapons platform. Various X-craft provided the answers that allowed the next generation of aircraft to be designed.

I agree with aquanaut99. Space is the last place we should be militarising.

Back to Jim again...

I admit that I don't know that an orbital vehicle launching a missile would be more or less detectable than launching from the ground. That said, I reason or suppose that, unless all of LEO is being observed, you could launch something from something already in LEO without it being noticed, or noticed in time to matter.

I'm a former accountant, not an engineer so I bow to you on orbital mechanics but it seems to me, if you've got a weapon platform & a target satellite in a 45 degree inclined orbit at the same (or almost the same) height then you should be able to shoot from one to the other without too much trouble.

If the target is heading southeast & the launch vehicle is heading northeast & they're going to pass close to each other, surely a missile from one would hit the other at 90 degrees with only a short flight time. Intercepting an incoming warhead (ICBM's, say) is tricky but a satellite? You'd have its orbit plotted in & you'd know where it was going to be.

And Jim again...

Yes, I disapprove (not that that means anything, I know) of the DOD/NRO hiding their earlier efforts too.

My point about SSTO, which, truth be told, I didn't put forward well, was that anything learned by a classified program which might be of use to a civilian SSTO program, won't be made available.

I don't think I mentioned GPS or GSO.

Anyway, perhaps it would be useful to ask, what is the X-37 for? A manned mini-spaceplane? Dream Chaser is already there so it seems like unnecessary duplication. If it's not intended to lead to a weapons platform, then what is it for?

[Jim]

Wow, Jim had a lot to say...

Ok, yes, you're right - the X-37 IS a test vehicle & not intended to be a weapon itself. The upcoming X-37C (bigger)

There is no upcoming X-37C.  It is just dead proposal.

[Jim]

Anyway, perhaps it would be useful to ask, what is the X-37 for? A manned mini-spaceplane? Dream Chaser is already there so it seems like unnecessary duplication. If it's not intended to lead to a weapons platform, then what is it for?

The X-37 predates Dreamchaser by 10 years.
X-37 is a reusable spacecraft platform. 

[Jim]

I'm still of the opinion that it is intended to pave the way for a small orbital weapons platform.

It has no relation to orbital weapons platforms.