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GIGANTIC Aviation Week story, Pentagon has been flying 2-stage orbital spaceplane throughout 1990s&#
Guest_BruceMoomaw_*
post Mar 6 2006, 02:24 AM
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It may even have been manned:
http://www.aviationnow.com/avnow/news/chan...ws/030606p1.xml

My God, what a story -- if it's even partially true. And, judging from this article, they are absolutely certain they have proof (along with proof that the thing, although it works, has recently been mothballed as not
cost-effective).

It's important to keep in mind, though, that this thing is NOT a workable prototype of the originally planned 2-stage winged Space Shuttle. The second stage -- the spaceplane that actually achieved orbit -- was relatively small and probably very inefficient as a cargo carrier; its advantage lay in allowing the US to get a military reconaissance (or weapons) satellite into orbit surreptitiously, with no advance warning of the launch going to other countries. Even at that, as I say, AW reports that the thing has been recently canned as not worth its (doubtless huge) black-budget expense.
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tasp
post Mar 6 2006, 02:56 AM
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QUOTE (BruceMoomaw @ Mar 5 2006, 08:24 PM) *
It may even have been manned:
http://www.aviationnow.com/avnow/news/chan...ws/030606p1.xml

My God, what a story -- if it's even partially true. And, judging from this article, they are absolutely certain they have proof (along with proof that the thing, although it works, has recently been mothballed as not
cost-effective).

It's important to keep in mind, though, that this thing is NOT a workable prototype of the originally planned 2-stage winged Space Shuttle. The second stage -- the spaceplane that actually achieved orbit -- was relatively small and probably very inefficient as a cargo carrier; its advantage lay in allowing the US to get a military reconaissance (or weapons) satellite into orbit surreptitiously, with no advance warning of the launch going to other countries. Even at that, as I say, AW reports that the thing has been recently canned as not worth its (doubtless huge) black-budget expense.



Sundstrand (maker of aircraft electrical power generators) put together a proposal for a new electrical generating system for the SR-71 in the very late 80s or early 90s.

It was assumed (by those of us at a 'low level') that the generators would not, in fact, be used on an SR-71.

I would suspect they were for the carrier craft.


Always wondered what they were up to . . . .

blink.gif



Wonder what the $ per pound for LEO is with this system and if it is competitive with . . .
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mcaplinger
post Mar 6 2006, 02:58 AM
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Interesting, but I don't think AW&ST's track record on this sort of thing is too good. For every success (they broke the story of the F-117, IIRC) there are two or three questionable bits of uncorroborated science fiction. I'm remembering a story they did in the early '90s on a saucer-shaped military aircraft that was powered by the Earth's magnetic field, or some similar bit of fringe science. And of course there's the "donuts on a rope" pulse-detonation engine sightings, "Darkstar November", etc.

Not for nothing is it called "Aviation Leak and Space Mythology." smile.gif


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Disclaimer: This post is based on public information only. Any opinions are my own.
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Guest_BruceMoomaw_*
post Mar 6 2006, 03:44 AM
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Whatever happened to the "donuts on a rope" story? I remember the photos from that story, and the magazine was reporting auditory observations of the supposed pulse-engine long before that.
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deglr6328
post Mar 6 2006, 06:30 AM
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Completely fascinating. Virtually all the details seem to be very plausible. Except for one glaring oddity. The section stating: "The spaceplane is capable of carrying an advanced imaging suite that features 1-meter-aperture adaptive optics with an integral sodium-ion-sensing laser. By compensating in real-time for atmospheric turbulence." makes no sense. Sodium lasers used for AO are used to create artificial guide stars in the earth's natrual sodium layer at ~90 km up. If you are orbiting and looking down, this is useless to you. >90% of the phase altering atmospheric turbulence occurs below this layer and shinging a bright yellow laser DOWN, to say nothing of its utterly unacceptable use in a clandestine situation, would do virtually nothing for you in terms of image sharpening. I have little doubt that this thing exists (how else could they've dumped the SR-71??!) but there are a few little things that make it seem like while they were getting the story at least a few people wanted to have a little fun with them.
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Guest_BruceMoomaw_*
post Mar 6 2006, 07:54 AM
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Jeffrey Bell, that eternal party-pooper, caught not only that one but a large set of what look like additional downright fatal errors in the whole story, to wit:
______________________________________


This story is riddled with absurdities:

"A large 'mothership,' closely resembling the U.S. Air Force's historic
XB-70 supersonic bomber, carries the orbital component conformally under
its fuselage, accelerating to supersonic speeds at high altitude before
dropping the spaceplane. The orbiter's engines fire and boost the
vehicle into space."

Starting out from Mach 3 and ~100,000' will not give enough of a boost
that a small single-stage vehicle can reach orbit, or even a once-around
trajectory. Whoever wrote this article has been reading too much
t/space propaganda.

"The manned orbiter's primary military advantage would be surprise
overflight. There would be no forewarning of its presence, prior to the
first orbit, allowing ground targets to be imaged before they could be
hidden."

Soviet missile-warning satellites would pick up the IR plume from the
second stage, and since it would not be at a known space launch site
they would interpret it as a covert nuclear missile launch. At a minimum
you would get a major diplomatic crisis, at worst an accidental nuclear war!

"The spaceplane is capable of carrying an advanced imaging suite that
features 1-meter-aperture adaptive optics with an integral
sodium-ion-sensing laser."

This technology only works looking up, not down. The turbulent layer in
the atmosphere is close to the ground and far away from orbit. You
don't need it in space (besides the provocation of firing a laser at a
Soviet installation from orbit).

"The orbiter's belly appears to be contoured with channels, riblets or
'strakelets' that direct airflow to engine inlets and help dissipate
aerodynamic heating. These shallow channels may direct air to a complex
system of internal, advanced composite-material ducts, according to an
engineer who says he helped build one version of the orbiter in the
early 1990s."

Composite materials are held together with epoxy glue and are highly
flammable (see DC-X fires). You need Ti or steel for hypersonic intake
ducts because the air is red-hot.

"One version of the B-70 could have been used as a recoverable booster
system to launch things into low-Earth orbit. . . . The DynaSoar
program, the first effort by the [U.S.] to use a manned boost-glider to
fly in near-orbital space and return, was considered in this context in
November 1959. The B-70 was to carry the 10,000-lb. DynaSoar glider and
a 40,000-lb. liquid rocket booster to 70,000 ft. and release them while
traveling at Mach 3. With this lofty start, the booster could then push
the glider into its final 300-mi. orbit."

Again, the rocket equation tells you this won't work. You would need
something bigger than Titan II for the booster and that is far too heavy
for the B-70 to lift. North American was notorious in those days for
proposing unworkable ideas, e.g. the orbital X-15.

So to me, this article has as much credibility as last year's article on
spaceships powered by zero-point energy. It seems that AvWeek's staff
now lacks even basic technical knowledge.
__________________________________________

Which presumably means that I do too, since I didn't catch any of this at the time. Put not your trust in Aviation Week, apparently (although I still wonder if this may have been a distorted version of a real story).
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Guest_Myran_*
post Mar 6 2006, 11:36 AM
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Thats very insightful deglr6328, and without enough knowledge about engineering and the feasability of a spaceplane as the one described. The part about a sodium laser guidance for adaptive optics that look down is what caught my attention.
In fact I thought it sounded like complete hogwash since they would have a 'guide star' compensating for the very thin upper part of the atmosphere that way.

But I wouldnt say that the rest of the details seems likely, theres one other and BruceMoomaw pointed it out (or was that a quote?) The launch of the upper stage would be tracked by the Soviet early warning system and cause a number of alarms from the infrared signature as well as tracking radar while in orbit, yes they were fully able to track objects in low orbit around the Earth especially those flying over their own territory. Yet there have been no diplomatic crizis over anything resembling this, and I have kept track of such even those caused by simple sounding rockets fired from ESRANGE.

So only from these two viewpoints I have to say that we should not put that much trust in this story.
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paxdan
post Mar 6 2006, 11:37 AM
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The set up described reminds me of the Tagboard project utilising a modified A-12 (which was the precursor to the YF-12 and SR-71) known as the M-21.

Here is a picture of the M-21 and D-21. The program described in the AW&ST article sounds like the logical extension of the research avenue.

I would be supprised if something along the lines described in the article didn't exist, even if it is just an unmanned test vehicle, strapped to the belly of a supersonic bomber.
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Bob Shaw
post Mar 6 2006, 11:44 AM
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Jeffrey Bell is really worried about the threat from the Soviet Union, isn't he? I'm glad he never makes any, er, unsubstantiated statements!

On a more serious note, I'm sure that the DoD would have loved a black manned orbital capability, especially if it could be seen as an SR-71 follow-on (so pilots woulda had to be involved). And after Challenger, the DoD were no longer committed to the Shuttle they'd halfway designed, so yes, it kinda makes sense. However, not quite *enough* sense.

I'd be prepared to believe in a number of black projects, including air-launched not-quite-orbital unmanned payloads, covert ops insertion and rescue vehicles, an unmanned SR-71 replacement and so forth, but sadly I can't really buy DynaSoar Mk II.

Bob Shaw


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Remember: Time Flies like the wind - but Fruit Flies like bananas!
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edstrick
post Mar 6 2006, 12:00 PM
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ET Phone Area-51?

Actually, I've recently read another CG animated movie in the works is "Escape from Area-51"... in which a group of captive ET's break out of Area 51 in a "great escape". Sounds funnier than a lot of lame hollywood ideas to me!
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Bob Shaw
post Mar 6 2006, 01:25 PM
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Here are grabs from the AW&ST website:

http://www.aviationnow.com/avnow/news/chan...ws/030606p1.xml

Bob Shaw
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Ames
post Mar 6 2006, 02:16 PM
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Where does the undercarriage go?

doesn't "look" right

Nick
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tty
post Mar 6 2006, 07:56 PM
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Actually this is a rather typical Jeff Bell effort. Partly true, partly exaggerated and partly nonsensical

QUOTE
This story is riddled with absurdities:

"A large 'mothership,' closely resembling the U.S. Air Force's historic
XB-70 supersonic bomber, carries the orbital component conformally under
its fuselage, accelerating to supersonic speeds at high altitude before
dropping the spaceplane. The orbiter's engines fire and boost the
vehicle into space."

Starting out from Mach 3 and ~100,000' will not give enough of a boost
that a small single-stage vehicle can reach orbit, or even a once-around
trajectory. Whoever wrote this article has been reading too much
t/space propaganda.


Actually it just about would. It would cut the deltavee needed for LEO from 9.5-10 kms-1 to something like 8.5 kms-1. With an Isp of 450 s (similar to the Shuttle main engine or the X-33 aerospike engine) this would require a fuel fraction in the 80-85% range which is perfectly practical for a small single stage ELV with a recoverable Corona-style capsule. Whether it is practical for a spaceplane is perhaps more dubious.


QUOTE
"The manned orbiter's primary military advantage would be surprise
overflight. There would be no forewarning of its presence, prior to the
first orbit, allowing ground targets to be imaged before they could be
hidden."

Soviet missile-warning satellites would pick up the IR plume from the
second stage, and since it would not be at a known space launch site
they would interpret it as a covert nuclear missile launch. At a minimum
you would get a major diplomatic crisis, at worst an accidental nuclear war!



Fortunately the Soviet Union doesn't exist any longer, and even when it did I don't think they would have started a nuclear war every time a smallish missile or sounding rocket was launched anywhere in the World.



QUOTE
"The spaceplane is capable of carrying an advanced imaging suite that
features 1-meter-aperture adaptive optics with an integral
sodium-ion-sensing laser."

This technology only works looking up, not down. The turbulent layer in
the atmosphere is close to the ground and far away from orbit. You
don't need it in space (besides the provocation of firing a laser at a
Soviet installation from orbit).


True

QUOTE
"The orbiter's belly appears to be contoured with channels, riblets or
'strakelets' that direct airflow to engine inlets and help dissipate
aerodynamic heating. These shallow channels may direct air to a complex
system of internal, advanced composite-material ducts, according to an
engineer who says he helped build one version of the orbiter in the
early 1990s."

Composite materials are held together with epoxy glue and are highly
flammable (see DC-X fires). You need Ti or steel for hypersonic intake
ducts because the air is red-hot.


This is the nonsense part. Titanium and steel besides being heavy are useless at hypersonic speeds. The X-15 used them, and that was about the end of the line. There was repeated problems with heat damage and when the X-15 was modified to exceed Mach 6 an ablative coating had to be added (and even so there was serious damage on that Mach 6.72 record flight).
Apparently Bell is unaware that more than one type of composite material exists. Actually just about the only feasible material would be SiC-coated RCC composite.

QUOTE
"One version of the B-70 could have been used as a recoverable booster
system to launch things into low-Earth orbit. . . . The DynaSoar
program, the first effort by the [U.S.] to use a manned boost-glider to
fly in near-orbital space and return, was considered in this context in
November 1959. The B-70 was to carry the 10,000-lb. DynaSoar glider and
a 40,000-lb. liquid rocket booster to 70,000 ft. and release them while
traveling at Mach 3. With this lofty start, the booster could then push
the glider into its final 300-mi. orbit."

Again, the rocket equation tells you this won't work. You would need
something bigger than Titan II for the booster and that is far too heavy
for the B-70 to lift. North American was notorious in those days for
proposing unworkable ideas, e.g. the orbital X-15.


Since the Dyna Soar was meant to be launched from the ground by a Titan III it seems to me a rather smaller booster would suffice. A 40,000 lb booster does sound a bit on the small side to reach orbit, but not absurdly so.

tty
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Guest_BruceMoomaw_*
post Mar 6 2006, 10:53 PM
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QUOTE (tty @ Mar 6 2006, 07:56 PM) *
Fortunately the Soviet Union doesn't exist any longer, and even when it did I don't think they would have started a nuclear war every time a smallish missile or sounding rocket was launched anywhere in the World.


Whoa, horsey. Russia -- under Yeltsin -- damn near started one in Jan. 1995 after misinterpreting the launch of a Norwegian scientific sounding rocket, which was far smaller than this thing would be. (See the Nov. 1997 "Scientific American" for the grisly details.) And, as I understand it, there were some very close calls earlier, during the Soviet days -- and not just on the Soviet side.

You couldn't use the Spaceplane to sneak up on Russia, or any other nation that had missile-launch warning satellites -- but does even China have those? I don't think so. However, even if we decided to use the Spaceplane against nations that did lack that ability, the US would have had to inform Russia about the existence of the thing, while demanding that Russia keep the information to itself -- which is decidedly shaky practically.

Regarding some of your other points:

(1) "Actually it just about would. It would cut the deltavee needed for LEO from 9.5-10 kms-1 to something like 8.5 kms-1. With an Isp of 450 s (similar to the Shuttle main engine or the X-33 aerospike engine) this would require a fuel fraction in the 80-85% range which is perfectly practical for a small single stage ELV with a recoverable Corona-style capsule. Whether it is practical for a spaceplane is perhaps more dubious."

But what you're talking about is just the equivalent of a Pegasus-type launch for military purposes. Maybe worth doing (if you ignore the difficulties mentioned above about Russia detecting the launch and spilling the beans), but hardly revolutionary.

(2) "Since the Dyna Soar was meant to be launched from the ground by a Titan III it seems to me a rather smaller booster would suffice. A 40,000 lb booster does sound a bit on the small side to reach orbit, but not absurdly so."

But a Titan 2 was needed to put Gemini into orbit -- and Dyna-Soar weighed 1/3 more. Even given the initial boost from the XB-70 (which might substitute for the Titan 2's first stage, I suppose, since I haven't yet checked their comparative speeds and payload masses), you'd need a very large second stage -- surely weighing more than 20 tons.

So: I remain in the position, at this point, of pooh-poohing my own earlier Electrifying Announcement. Pretty much the story of my life.
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Guest_BruceMoomaw_*
post Mar 6 2006, 11:15 PM
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Footnote: the Titan 2 second stage weighed 29,000 kg. I can't find any information on the velocity of the first stage at burnout on a Gemini launch -- but clearly, unless the B-70 was moving at MUCH higher velocity than the Titan first stage and/or the second stage used much more efficient propellant than that in the Titan 2 second stage, there is no conceivable way a 40,000-pound second stage would be adequate to put a Dyna-Soar in orbit.
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