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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
Post #1





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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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Guest_BruceMoomaw_*
post Mar 6 2006, 07:54 AM
Post #2





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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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tty
post Mar 6 2006, 07:56 PM
Post #3


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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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Posts in this topic
- BruceMoomaw   GIGANTIC Aviation Week story   Mar 6 2006, 02:24 AM
- - tasp   QUOTE (BruceMoomaw @ Mar 5 2006, 08:24 PM...   Mar 6 2006, 02:56 AM
- - mcaplinger   Interesting, but I don't think AW&ST's...   Mar 6 2006, 02:58 AM
- - BruceMoomaw   Whatever happened to the "donuts on a rope...   Mar 6 2006, 03:44 AM
- - deglr6328   Completely fascinating. Virtually all the details...   Mar 6 2006, 06:30 AM
|- - Bob Shaw   Jeffrey Bell is really worried about the threat fr...   Mar 6 2006, 11:44 AM
- - BruceMoomaw   Jeffrey Bell, that eternal party-pooper, caught no...   Mar 6 2006, 07:54 AM
|- - paxdan   The set up described reminds me of the Tagboard pr...   Mar 6 2006, 11:37 AM
|- - tty   Actually this is a rather typical Jeff Bell effort...   Mar 6 2006, 07:56 PM
- - Myran   Thats very insightful deglr6328, and without enoug...   Mar 6 2006, 11:36 AM
- - edstrick   ET Phone Area-51? Actually, I've recently rea...   Mar 6 2006, 12:00 PM
|- - Bob Shaw   Here are grabs from the AW&ST website: http:/...   Mar 6 2006, 01:25 PM
- - Ames   Where does the undercarriage go? doesn't ...   Mar 6 2006, 02:16 PM
- - BruceMoomaw   QUOTE (tty @ Mar 6 2006, 07:56 PM) Fortun...   Mar 6 2006, 10:53 PM
- - BruceMoomaw   Footnote: the Titan 2 second stage weighed 29,000 ...   Mar 6 2006, 11:15 PM
|- - tasp   QUOTE (BruceMoomaw @ Mar 6 2006, 05:15 PM...   Mar 7 2006, 02:59 AM
|- - Bob Shaw   QUOTE (tasp @ Mar 7 2006, 02:59 AM) We ca...   Mar 7 2006, 10:23 AM
|- - Bob Shaw   One *possible* vehicle which may form part of a so...   Mar 7 2006, 04:36 PM
- - tty   Well, I’ve been doing some more figuring and I mus...   Mar 7 2006, 08:43 PM
- - dvandorn   Just a little gedankenexperiment, here -- anyone c...   Mar 7 2006, 09:48 PM
|- - AlexBlackwell   QUOTE (dvandorn @ Mar 7 2006, 09:48 PM) J...   Mar 7 2006, 09:57 PM
|- - Bob Shaw   QUOTE (dvandorn @ Mar 7 2006, 09:48 PM) J...   Mar 7 2006, 10:08 PM
|- - JTN   QUOTE (Bob Shaw @ Mar 7 2006, 10:08 PM) C...   Mar 7 2006, 10:44 PM
- - dvandorn   Good point, Alex -- NRO probably would run such an...   Mar 7 2006, 10:02 PM
- - dvandorn   I'm not trying to imply conspiracies -- though...   Mar 7 2006, 10:32 PM
- - dvandorn   I have to admit, when I saw the Blackstar story, t...   Mar 7 2006, 10:57 PM
- - BruceMoomaw   According to the article, not even the nation...   Mar 8 2006, 01:26 AM
- - GregM   So let’s see here. To start with we have the Valky...   Mar 8 2006, 04:02 AM
- - tty   Also remember that there is a school of thought th...   Mar 8 2006, 07:24 AM
|- - paxdan   Lots of info about the XB-70 What an aircraft...   Mar 8 2006, 09:58 AM
|- - Bob Shaw   Jim Oberg on MSNBC.Com Space News summed up the Bo...   Mar 8 2006, 11:09 AM
|- - Steve G   QUOTE (paxdan @ Mar 8 2006, 02:58 AM) Lot...   Mar 17 2006, 02:56 AM
|- - GregM   QUOTE (Steve G @ Mar 17 2006, 02:56 AM) I...   Mar 17 2006, 03:45 AM
|- - dvandorn   In re the Avro Arrow: QUOTE (GregM @ Mar 16 ...   Mar 18 2006, 03:19 PM
|- - Steve G   QUOTE (dvandorn @ Mar 18 2006, 08:19 AM) ...   Mar 18 2006, 09:03 PM
- - BruceMoomaw   It should be remembered that there is still -- to ...   Mar 8 2006, 11:04 AM
|- - paxdan   QUOTE (BruceMoomaw @ Mar 8 2006, 11:04 AM...   Mar 8 2006, 11:11 AM
|- - tty   [quote name='BruceMoomaw' date='Mar 8 ...   Mar 8 2006, 11:18 PM
|- - gndonald   QUOTE (BruceMoomaw @ Mar 8 2006, 07:04 PM...   Mar 17 2006, 04:14 PM
|- - Bob Shaw   QUOTE (gndonald @ Mar 17 2006, 04:14 PM) ...   Mar 17 2006, 08:40 PM
|- - ljk4-1   QUOTE (Bob Shaw @ Mar 17 2006, 03:40 PM) ...   Mar 17 2006, 09:38 PM
- - edstrick   I believe "AirCraftFilms", the companion...   Mar 8 2006, 12:41 PM
- - BruceMoomaw   QUOTE (Bob Shaw @ Mar 8 2006, 11:09 AM) J...   Mar 8 2006, 01:27 PM
|- - ljk4-1   I found this post from the FPSPACE list very inter...   Mar 8 2006, 02:49 PM
|- - AlexBlackwell   QUOTE (BruceMoomaw @ Mar 8 2006, 01:27 PM...   Mar 8 2006, 04:48 PM
- - BruceMoomaw   QUOTE (AlexBlackwell @ Mar 8 2006, 04:48 ...   Mar 9 2006, 12:39 AM
|- - ljk4-1   It is a known fact that the CIA and USSR "sup...   Mar 9 2006, 03:56 PM
|- - AlexBlackwell   QUOTE (BruceMoomaw @ Mar 9 2006, 12:39 AM...   Mar 9 2006, 04:55 PM
- - BruceMoomaw   Okay, but a magazine which (according to you) is c...   Mar 9 2006, 09:17 PM
|- - AlexBlackwell   QUOTE (BruceMoomaw @ Mar 9 2006, 09:17 PM...   Mar 9 2006, 09:32 PM
- - BruceMoomaw   QUOTE (AlexBlackwell @ Mar 9 2006, 09:32 ...   Mar 10 2006, 05:24 AM
|- - Bob Shaw   From Wikipedia: "One notable variant of the ...   Mar 10 2006, 09:46 AM
|- - ljk4-1   Blackstar: False Messiah From Groom Lake http://w...   Mar 10 2006, 12:16 PM
- - BruceMoomaw   Bell, having now read the two other Aviation Week ...   Mar 11 2006, 11:31 AM
|- - Bob Shaw   Is it a bad sign when Jeffrey Bell starts agreeing...   Mar 11 2006, 11:37 AM
|- - gpurcell   QUOTE (Bob Shaw @ Mar 11 2006, 11:37 AM) ...   Mar 12 2006, 02:23 AM
- - tty   Here it is Jeff Bell who is off speculating in the...   Mar 12 2006, 04:45 PM
|- - Bob Shaw   QUOTE (tty @ Mar 12 2006, 04:45 PM) If yo...   Mar 12 2006, 09:17 PM
- - ljk4-1   Six blind men in a zoo: Aviation Week's mythic...   Mar 13 2006, 05:13 PM
|- - AlexBlackwell   QUOTE (ljk4-1 @ Mar 13 2006, 05:13 P...   Mar 13 2006, 05:25 PM
|- - helvick   QUOTE (AlexBlackwell @ Mar 13 2006, 05:25...   Mar 13 2006, 06:04 PM
- - gpurcell   Ouch, that's GOTTA hurt.   Mar 13 2006, 07:01 PM
- - tty   Just one small point. That nuclear-powered soviet ...   Mar 13 2006, 07:05 PM
- - ljk4-1   This Web page has excerpts from the 1958 AW&ST...   Mar 13 2006, 07:29 PM
- - Myran   Two US built nuclear jet engines at Idaho National...   Mar 13 2006, 09:53 PM
- - BruceMoomaw   Having finally read all of Dwayne Day's story,...   Mar 18 2006, 03:51 AM
|- - Bob Shaw   QUOTE (BruceMoomaw @ Mar 18 2006, 03:51 A...   Mar 18 2006, 01:36 PM
|- - gpurcell   QUOTE (Bob Shaw @ Mar 18 2006, 01:36 PM) ...   Mar 18 2006, 01:58 PM
|- - BruceMoomaw   QUOTE (gpurcell @ Mar 18 2006, 01:58 PM) ...   Mar 19 2006, 01:16 AM
|- - AlexBlackwell   QUOTE (BruceMoomaw @ Mar 19 2006, 01:16 A...   Mar 20 2006, 05:13 PM
- - ljk4-1   http://www.janes.com/defence/air_forces/ne...60406...   Apr 12 2006, 06:23 PM
- - BruceMoomaw   Four more Aviation Week letters on the BlackStar s...   Apr 21 2006, 01:20 PM
- - tty   Piggybacking on a B-70 would not be a good idea ae...   Apr 21 2006, 05:07 PM
- - ljk4-1   Black projects don't seem to be having any bud...   May 23 2006, 07:09 PM
- - climber   I heard this week on the radio that the whole USA ...   May 23 2006, 07:34 PM
- - ljk4-1   Looks like they had a plan similar to the one from...   May 23 2006, 08:15 PM


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