Pegasus launch from Valkyrie (or ...
Vincent Cate
George William Herbert:
>Pegasus is a three-stage winged [first stage] solid rocket able to launch
>600 lbs into a 250nm polar orbit or 900 lbs into a 250nm equitorial orbit.
>
>The vehicle itself is 49.2 feet long, with a diameter of 48 inches and a
>wingspan of 22 feet. It weighs 40,000 pounds at launch ...
>
>The launch costs are estimated at $8 million per launch, or about $10,000
>per pound to orbit. This is unfavorable compared to other launchers on a
>per pound basis, but the small total cost remains attractive to those not
>needing large payloads. It is considerably better than other small launchers.
So the 1,000 MPH difference due to the rotation of the Earth results in a
300 lb payload difference. Clearly if you had a plane that could fly South
at 1,600 MPH instead of the 600 MPH that the B-52 does you could get the
300 lbs back. At $10,000/lb, this extra 300 lbs is worth $3,000,000.
I don't really know what current planes could carry 40,000 lbs at such speeds;
however, I know that the North American XB-70 Valkyrie flew at 2,000 MPH,
could weigh over 500,000 lbs on takeoff and carried up to 300,000 lbs of fuel.
It was designed to be a bomber (B-70) but became an experimental aircraft (XB-70)
when funding was cut. It flew at over 70,000 feet. The extra 30,000 feet over
the B-52 and the extra 1,400 MPH would really be nice for launching something
like the Pegasus. This might have made the equitorial launch go from a 900 lb
payload to 1,400 lbs or more. In other words, if the Valkyrie were used instead
of the B-52, it might add $5,000,000 to the value of the launch.
Unfortunately, the Valkyrie stopped flying 20 years ago. In the 25 years since
the Valkyrie came out, has there been another plane that was better for launching
something like the Pegasus into orbit?
Does anything come close to the Valkyrie?
What can the B-1 and B-2 do?
The B-52 is really the first stage in the Pegasus out of a total of 4 stages.
In general it seems that using a high and fast plane as the true first stage should
be a great way to reduce the cost of getting a payload into orbit.
The space plane idea of taking the whole plane all the way into orbit seems wrong.
Multiple stages really are a good idea. A plane that flew to 6,000 MPH (which I think
they might be able to do using hydrogen powered scram jets) would eliminate the need
for the "first stage" on the Pegasus. This is most of the rocket. This would
have to reduce costs alot. A really fast plane that could carry a rocket makes far
more sense than a plane that goes all the way to orbit.
How soon will there be a hyrogen powered scram-jet plane?
Are there any other planes that have interesting possibilities?
-- Vince
Allen W. Sherzer
>I don't really know what current planes could carry 40,000 lbs at such speeds;
I was wondering if a FB-111 would do? My copy of Janes says it will carry a
bomb load of 37,500 which is pretty close. Perhaps you could upgrade the
engines to P&W F100's for the extra thrust needed. However, I have NO idea
how you would integrate the Pegasus with the FB-111. The only thing I could
think of is to add a centerline station (use the internal bay for more fuel)
and mount the aircraft and Pegasus on a magnetically levitated platform. This
would allow the 111 to take off wiht gear up, launch the Pegasus and land
with its regular gear. I know the Air Force is looking at similar platforms
to allow aircraft to take off from cratered airstrips.
The main advantage to this however, would be cost and not more altitude/
speed. OSI is looking at buying/leasing a 747 for non DoD launches. They
could buy a FB-111 (if the line is still open and tooling is available)
for a lot less than a 747. There is of course, also the added risk of changes
to the 111 which will be needed.
Just thinking out loud
Allen
-----------------------------------------------------------------------------
| Allen W. Sherzer | If guns are outlawed, |
| a...@iti.org | how will we shoot the liberals? |
-----------------------------------------------------------------------------
Henry Spencer
Pegasus might need some redesign for this, however, given the thinner air
and greater aerodynamic heating. It's really a pity that XB-70 #2 crashed,
since it had the definitive control systems and generally solved some of
#1's problems. (#2's crash was one of the things that killed proposals
for an XB-70-launched successor to the X-15.)
>...In the 25 years since the Valkyrie came out, has there been another
>plane that was better for launching something like the Pegasus into orbit?
>Does anything come close to the Valkyrie?
In a word, no. Highly-supersonic flight has largely gone out of fashion
for military purposes. (This was one of the reasons the B-70 died.) An
SR-71 just might be capable of it, although its career as a drone launcher
was cut short by a nasty separation accident that wrote off both drone
and SR-71. That only marginally counts, since the SR-71 dates back to
the same era as the XB-70.
(Say, I wonder what the payload of a Foxbat is...! :-))
>What can the B-1 and B-2 do?
The B-1A was supersonic, but not greatly so; I think the B-1B abandoned
supersonic capability when its engine inlets were redesigned to reduce
radar signature. The B-2 is subsonic.
>How soon will there be a hyrogen powered scram-jet plane?
Apart from the Aerospace Plane, whose future is uncertain, West Germany's
Saenger project -- aimed at a reusable space launcher with a hypersonic
jet as the first stage -- is the only serious effort even talking about
such a thing. It has no other civilian applications, and the military
prefers flying low and slow nowadays.
--
With features like this, | Henry Spencer at U of Toronto Zoology
who needs bugs? | uunet!attcan!utzoo!henry he...@zoo.toronto.edu
Allen W. Sherzer
>>>I don't really know what current planes could carry 40,000 lbs at such speeds;
>>I was wondering if a FB-111 would do?
>It's not exactly in the same speed class as B-70 or FB-111,
Agreed. What I was thinking was that it might be a lot cheaper to buy and
operate a FB-111. I believe 747's cost ~$150 mil but a doubt a FB-111 costs
more that ~$70 mil. I don't know about operating costs however.
After I wrote the above another thought occured to me. Using a 747 or B-52
they could launch 2 or 3 at a time. Anybody know if there are any plans to
do that?
David Smith
>
>I was wondering if a FB-111 would do?
It's not exactly in the same speed class as B-70 or FB-111, but I saw an
article several years ago (in AW&ST?) about an idea for a small propane+LOX
space plane with a large drop tank, to be air launched from the back of a 747.
Not just an ordinary 747. This one had an SSME mounted in the tail to get a
healthy climb rate at a steep angle.
--
David R. Smith, HP Labs | "It is said that St. Patrick drove the
dsm...@hplabs.hp.com | snakes out of Ireland. They were last seen
(415) 857-7898 | selling junk bonds." -- Johnny Carson
Henry Spencer
>>... what current planes could carry 40,000 lbs at such speeds;
>
>I was wondering if a FB-111 would do? My copy of Janes says it will carry a
With such loads it is almost certainly subsonic, giving no advantage over
the B-52. The F-111 family is generally overweight and underpowered, and
is "supersonic" only by courtesy. :-) It's vanishingly unlikely that any
of them could reach, say, Mach 2 with a heavy external load.
A B-58 might be able to do it, if there were any of them left. It was
*designed* to carry a heavy external load supersonic, since it had no
bomb bay -- its bomb was built into its huge drop tank. There may still
be some left in storage at Davis-Monthan or related places, but it would
probably be difficult and expensive to refurbish one, even assuming the
USAF would sell you one.
Henry Spencer
>Not just an ordinary 747. This one had an SSME mounted in the tail to get a
>healthy climb rate at a steep angle.
Actually, later they discarded the SSME idea in favor of burning hydrogen
in the bypass ducts of the turbofans! As I recall, it more than doubles
the thrust and will not hurt the engine if you don't do it for more than
about 30 seconds.
The biggest problem with using a 747 as a first stage is simply the limited
cargo load. NASA's shuttle carrier has major structural reinforcements and
is still at the limit of what a 747 can do.
Al Bowers
>>What can the B-1 and B-2 do?
>The B-1A was supersonic, but not greatly so; I think the B-1B abandoned
>supersonic capability when its engine inlets were redesigned to reduce
>radar signature. The B-2 is subsonic.
B-1A was capable of Mach 2.2 at altitude. It had all sorts of ramps
and hydraulics in the inlets (not very stealthy) to do it though. The
B-1B is a Mach 1.2 bird at about 40,000 feet. The variable geometry
inlets were deleted to save cost (and improve stealth). There was
also a proposal to delete the wing sweep feature, but that was shot
down as it would have cost even more for the redesign to do so (?!?).
So we are left with a low altitude penetrator strategic bomber that
has a high altitude (marginally) supersonic capability that is not a
part of the specification. BTW, the F/A-18 has fixed inlets too and
has a reasonable supersonic capability (1.8) as does the F-16 (2.2).
--
Albion H. Bowers bow...@elxsi.dfrf.nasa.gov ames!elxsi.dfrf.nasa.gov!bowers
`In the changing of the times, they were like autumn lightning, a
thing out of season, an empty promise of rain that would fall unheeded
on fields already bare.'
attributed to Abe Shosaburo by Dave Lowery
Mark SOKOLOWSKI
as in the scenes that are shown in the film "outland", where the guys that
commit suicide by going into the wrong elevetor repaint the walls in red.
I suppose that given a boiling point for water at 37 degrees C at 1/20th
of an athmosphere, you body's fluid would be gazeified very rapidly.
But I have heard stories that the skin would be resistant enough to create
an internal pressure counteracting this effect. Any comments?
john.a.welsh
> In article <56...@hplabsb.HP.COM> dsm...@hplabsb.UUCP (David Smith) writes:
> >>>I don't really know what current planes could carry 40,000 lbs at such speeds;
>
> >>I was wondering if a FB-111 would do?
> >It's not exactly in the same speed class as B-70 or FB-111,
We have seen here that if you want to launch more with a Pegasus,
you need more speed in the booster plane. There is only 1 B70
left, and I don't think the Airforce Museum in Dayton will let
anybody use it (who would certify it air worthy, too?). So how
about the next fastest bomber, the B58? Were they all broken
up or are there other museum pieces around (other then Dayton's)?
A B58 held the coast to coast record that the SR71 broke (LA - NY
in about 2 hours) and they were in regular airforce service, so
they were not experimental oddities. They had external pods so
they could carry more than their bomb bays could hold, though I
am not sure if they could go supersonic with the pods (I think
they could). If we are discussing B70s here, why couldn't we have
a B58 launch Pegasus?
Henry Spencer
>[B-58] They had external pods so
>they could carry more than their bomb bays could hold, though I
The B-58 in fact had no bomb bay; *all* the payload was in the pod. And
yes, they could go supersonic with the pod in place, although the one
major constraint on going supersonic was "pod fuel tanks empty", which
might imply a constraint on how much weight could be in the pod at
supersonic speed.
Mary Shafer (OFV)
>We have seen here that if you want to launch more with a Pegasus,
>you need more speed in the booster plane. There is only 1 B70
>left, and I don't think the Airforce Museum in Dayton will let
>anybody use it (who would certify it air worthy, too?).
Somehow, I don't think that flying a stainless steel airplane
that's sat outside at Wright-Patterson, in the rain and snow,
for over a decade is a real good idea. I saw the rust weeping
from it.
>So how
>about the next fastest bomber, the B58? Were they all broken
>up or are there other museum pieces around (other then Dayton's)?
When last I looked, there was a B-58 sitting on the lakebed just
off Mercury Drive here at Edwards, destined for the museum. Of
course it's sat outside at Edwards, in the rain and snow, for over
a decade, but we have a lot less rain and snow and it's not stainless
steel, so it's probably a better idea.
>A B58 held the coast to coast record that the SR71 broke (LA - NY
>in about 2 hours) and they were in regular airforce service, so
>they were not experimental oddities. They had external pods so
>they could carry more than their bomb bays could hold, though I
>am not sure if they could go supersonic with the pods (I think
>they could). If we are discussing B70s here, why couldn't we have
>a B58 launch Pegasus?
The only drawback I see at first glance is that the B-58 is too close
to the ground. The gear wouldn't touch if there was a Pegasus under
the wing.
But this is also true of the F-111 and someone proposed a mag-lev cart
for takeoff. I believe that a largish fighter has taken off using a
ground-effect cart, rather than gear (although I can't confirm this
'til Monday, when I get to work and references).
Or you could put gear on Pegasus.
Or use fall-away gear like the outriggers on the U-2.
Actually, I thought that a large, high-wing plane like the C-5 or
C-141 would be the easiest to modify, but they're so _slow_.
--
Mary Shafer sha...@skipper.dfrf.nasa.gov ames!skipper.dfrf.nasa.gov!shafer
NASA Ames Dryden Flight Research Facility, Edwards, CA
Of course I don't speak for NASA
Mark Earnshaw
>The only drawback I see at first glance is that the B-58 is too close
>to the ground. The gear wouldn't touch if there was a Pegasus under
>the wing.
>
>But this is also true of the F-111 and someone proposed a mag-lev cart
>for takeoff. I believe that a largish fighter has taken off using a
>ground-effect cart, rather than gear (although I can't confirm this
>'til Monday, when I get to work and references).
>
>Or you could put gear on Pegasus.
>
>Or use fall-away gear like the outriggers on the U-2.
Would this cause trouble if something went wrong during the pre-launch part of
the flight? If the carrier plane were forced to land without actually having
launched Pegasus, then I assume that there would be problems if it had taken
off from a cart or had used fall-away gear. I suppose Pegasus could be ditched
somewhere (nearest body of water?), but I don't think that this would do it
or its payload much good.
Of course, if Pegasus' reliability is a guaranteed 100%, then this would not be
a concern. :-)
--------------------------------------------------------------------------------
Mark Earnshaw, Systems Design Engineering {uunet,utai}!watmath!watnow!mark
University of Waterloo, Ontario, Canada ma...@watnow.waterloo.{edu,cdn}
Henry Spencer
>to the ground. The gear wouldn't touch if there was a Pegasus under
>the wing.
Surely Pegasus would go in place of the B-58's bomb/fuel pod, under the
fuselage, not under a wing? The bomb pod was both longer (62ft) and
fatter (7-8ft) than Pegasus, and it weighed about as much (40klbs) at
takeoff, although drop weight was about half that and some work would
be needed to qualify the B-58 for dropping Pegasus. Clearance for the
Pegasus wing between the inboard engines looks adequate at first glance,
although I don't have B-58 drawings and it isn't a large aircraft. You
might have to fit a slot in the fuselage for Pegasus's tailfin (if OSC+H
ends up using a Tristar for commercial launches, such a slot will be
needed in it).
Allen W. Sherzer
>>I was wondering if a FB-111 would do? My copy of Janes says it will carry a
>>bomb load of 37,500 which is pretty close...
>With such loads it is almost certainly subsonic, giving no advantage over
>the B-52.
It might give a cost advantage. I understand B-52's are pretty expensive and
it is almost impossible to get parts.
>The F-111 family is generally overweight and underpowered, and
>is "supersonic" only by courtesy. :-)
Which is why I proposed upgrading the engines to F-100's which would
each add another 9,000 pounds of thrust.
>It's vanishingly unlikely that any
>of them could reach, say, Mach 2 with a heavy external load.
Agreed. However, it MAY be cheaper to operate than using a B-52 or 747.
This thread started as a way to reduce cost to orbit by increasing payload.
There are two ways to reduce cost to orbit. One is to increase the payload
and the other is to reduce operational cost. My postings on this address
the latter way.
IMHO if you don't use operational aircraft you will make it more expensive
to put a pound to orbit. There were lots of mach 2 aircraft out there, but
getting any operational just to add a few hundred pounds to payload won't
get you anything.
Mary Shafer (OFV)
>In article <SHAFER.90A...@skipper.dfrf.nasa.gov> sha...@skipper.dfrf.nasa.gov (Mary Shafer (OFV)) writes:
>>The only drawback I see at first glance is that the B-58 is too close
>>to the ground. The gear wouldn't touch if there was a Pegasus under
>>the wing.
Let me point out that it would be even worse if the Pegasus were under
the fuselage. I'm pretty sure that the B-58 gear would be a problem.
>>But this is also true of the F-111 and someone proposed a mag-lev cart
>>for takeoff. I believe that a largish fighter has taken off using a
>>ground-effect cart, rather than gear (although I can't confirm this
>>'til Monday, when I get to work and references).
>>
>>Or you could put gear on Pegasus.
>>
>>Or use fall-away gear like the outriggers on the U-2.
>Would this cause trouble if something went wrong during the pre-launch part of
>the flight? If the carrier plane were forced to land without actually having
>launched Pegasus, then I assume that there would be problems if it had taken
>off from a cart or had used fall-away gear. I suppose Pegasus could be ditched
>somewhere (nearest body of water?), but I don't think that this would do it
>or its payload much good.
Just punch it off over the PIRA (bombing range) going low and slow.
The payload should survive and the Pegasus will probably only need
refurbishment.
You'd have to put a kicker system on the pylon, of course, to push it
off the airplane at the launch condition, so a hung store won't be a
problem.
All of this discussion of the B-58 begs the real question, though: Why
in the world would OSC be so stupid as to tie themselves to the health
and welfare of an obsolete, barely supportable airplane?
We (Dryden) routinely fly obsolete airplanes and it is a real burden,
in terms of support logistics and up time. We only do it because
we've got them and, in many cases, don't have the money to replace
them. I don't think anyone here would recommend starting with an
obsolete airplane (we certainly never intended to have obsolete
planes; we've just ended up with them--sort of a process of
non-attrition :-).
Mark Gabriele
>We (Dryden) routinely fly obsolete airplanes and it is a real burden,
>in terms of support logistics and up time. We only do it because
>we've got them and, in many cases, don't have the money to replace
>them. I don't think anyone here would recommend starting with an
>obsolete airplane (we certainly never intended to have obsolete
>planes; we've just ended up with them--sort of a process of
>non-attrition :-).
I agree that in flying an obsolete plane in an operational role, there
are bound to be lots of obstacles. However, it might be worthwhile to
calculate the potential cost per pound savings, or the increase in
payload size, which might come of a Mach 2.2 Pegasus launch from a
higher altitude. I don't have the resources to make these
calculations - but I think it might be good to know that they had been
made, and that Pegasus was getting the most "bang for the buck" in its
choice of a launch platform.
=Mark
(gabr...@hub.toronto.edu)
Henry Spencer
>I am wondering wheter or not a human body exposed to void would explode,
Sigh, another one for our nonexistent frequently-asked-questions list...
From an earlier posting of mine on the subject:
Rapid decompression to low-grade vacuum has been tried (on animals).
Nobody's tried whole-body exposure to vacuum on humans, that I know of,
but exposing parts of the body (e.g. hands) has been done a fair bit.
Contrary to popular mythology, none of these awful things happen. The
animals exhibit some distress (understandable!) and after some seconds lose
consciousness. After repressurization they recover and show no serious
aftereffects. Parts of the human body in vacuum will swell somewhat
after a minute or so, but no particular pain is involved, there is no
explosion, and the effects seem to be fully reversible on recompression.
Loss of air from the lungs is inevitable, but the rate would normally be
limited by other factors (e.g. how big the hole in the wall was), and the
only significant hazard would be rupturing your eardrums if you had a cold
or otherwise didn't get your ears depressurized properly. There is some
cooling effect from evaporation of sweat, much as there is in air, but
vacuum has no temperature and there is no reason why you would "rapidly
freeze". And your skin is a good grade of leather, and does a good job
(temporarily!) of holding in your body water.
After ten minutes it would undoubtedly be different, but the only problem
with a brief exposure to vacuum is inability to breathe.
Brian or James
I believe that tests exposing humans to a soft vacuum were done
by Nazi Germany. The impression I have is that these tests were
done to destruction of the human subject, but I have no idea
what, if anything, was ever done with the results [or if the
records survived the war in any meaningful way]. This is a bit
like the hypothermia test the Germans did, in that while the
test procedure was inhumane, the results may have been put to
good use. To fend off flames, don't take this as a recommendation
that NASA or any other group start performing intentionally lethal
tests on humans.
As an aside, while the dogs involved in the '60s vacuuum exposure
tests were exposed until dead, for some reason the primates were not.
This is probably because of the cost of getting new primates, rather
than any primate prejudice.
JDN
Allen W. Sherzer
> I believe that tests exposing humans to a soft vacuum were done
>by Nazi Germany.
Yep. Goering wanted information on the effects of high altitude
on unprotected pilots. Goering also wanted information on the effects
on pilots who ditch in cold water to see what sort of protection they
would need. This lead to the hyperthermia experiments. There is an account
of this in "The Rise and Fall of the Third Reich". Pretty gruesom chapter.
>The impression I have is that these tests were
>done to destruction of the human subject,
Sometimes. More often, it was just done over and over to the same person.
Many survived the experiments but all were killed afterwards.
What a swell bunch of guys.
Steve Robiner
>In article <30...@calvin.cs.mcgill.ca> ms...@calvin.cs.mcgill.ca (Mark SOKOLOWSKI) writes:
>>I am wondering wheter or not a human body exposed to void would explode,
>
>explosion, and the effects seem to be fully reversible on recompression.
>
Well, in a similar situation, like SCUBA diving, sudden decompression
from 2 ATMs to 1 can be fatal, if not extremely painful. This may be
different from 1 ATM to 0, however.
In cases of emergency ascent, subject sometimes become unconscious shortly
after surfacing. Air embelisms or stroke may result if repressurization
is not implemented imeadiately. Air bubbles trapped in blood vessels are
extremely painful.
=steve=
Vincent Cate
Fraering Philip:
>The carrier airplane isn't the problem in terms of high launch cost.
>The Pegasus rocket itself might be.
Rockets are expensive, planes are really cheap to operate by comparison.
If there were a faster plane that could be used even if it were much
more expensive it would increase the payload to orbit so much that it
would be worth using. Remember, and increase of 300 lbs worth of payload
at $10,000/lb is worth $3,000,000. There are no planes that cost that
much per flight.
>A fully or partially reusable vehicle using RL-10 engines, similar to
>Third Millenium Inc.'s _original_ design for the Space Van, and with
>multiple stages, would probrably have a lower price.
Sounds interesting. Can you tell us more about this?
>So, in summary: please stop bugging Mary Shafer about which of the
>experimental aircraft in her stable at Dryden will improve the
>performance of a launcher that uses 325 Isp fuel when (although with
>a little more difficulty) 450 Isp fuel (Hydrogen/Oxygen) could be used
>instead. Think about it.
>
>Remember: The cost of developing Pegasus from point zero: $40 million.
>Cost of refurbishing B-70 Valkyrie: probrably lots more.
Part of the reason the Pegasus cost only $40 million to develop was that
they used the simpler fuel.
I did not really mean to suggest that we use the Valkyrie. I just knew
that 25 years ago we had a fast big plane and wondered if we had one
today. I see that we do not. Oh well.
Developing a plane to do this could save lots of money independent of
what type of rocket the plane actually launches. It should be able
to add millions to the value of the launch no matter what Isp the
fuel in the rocket is.
So, even if a redesigned Pegasus size rocket could have a lower
operating cost (as you imply - which lower Isp alone does not
guarantee) it might still be the case that it was better to spend
money on developing a fast plane than a cheaper rocket.
But, it looks like the fast plane would have to be built from
scratch which would cost lots of money. So, on to towing a Pegasus
with a 10 mile kevlar wire!!!!
-- Vince
Fraering Philip
About all of this talk about adapting the Pegasus to other airplanes:
It looks like y'all are really building up to a real goat-roping to me.
The carrier airplane isn't the problem in terms of high launch cost.
The Pegasus rocket itself might be.
Keep in mind that it took somewhere around $ 40 million to develop and
build, which is probrably less than some of the carrier aircraft being
proposed here.
A fully or partially reusable vehicle using RL-10 engines, similar to
Third Millenium Inc.'s _original_ design for the Space Van, and with
multiple stages, would probrably have a lower price.
Third Millenium was, as far as I can tell, unsucsessful at obtaining
investment capital. Of course, now that air-launch of spacecraft has
been shown to be possible, getting capital should be easier.
So, in summary: please stop bugging Mary Shafer about which of the
experimental aircraft in her stable at Dryden will improve the
performance of a launcher that uses 325 Isp fuel when (although with
a little more difficulty) 450 Isp fuel (Hydrogen/Oxygen) could be used
instead. Think about it.
Remember: The cost of developing Pegasus from point zero: $40 million.
Cost of refurbishing B-70 Valkyrie: probrably lots more.
Philip Fraering
dlbr...@pc.usl.edu
"I'm troubled, I'm dissatisfied, and I'm Irish." - Marianne Moore
Tom Neff
anything. People are properly posting articles addressing the *issue* --
not any specific person -- and Mary chooses to contribute because of
her interest in the subject.
--
"Of course, this is a, this is a Hunt, you |*==| Tom Neff
will -- that will uncover a lot of things. |===| tn...@bfmny0.UU.NET
You open that scab, there's a hell of a lot
of things... This involves these Cubans, Hunt, and a lot of hanky-panky
that we have nothing to do with ourselves." -- RN 6/23/72
Vincent Cate
Fraering Philip:
>So, in summary: please stop bugging Mary Shafer about which of the
>experimental aircraft in her stable at Dryden will improve the
>performance of a launcher that uses 325 Isp fuel when (although with
>a little more difficulty) 450 Isp fuel (Hydrogen/Oxygen) could be used
>instead. Think about it.
>
>Remember: The cost of developing Pegasus from point zero: $40 million.
>Cost of refurbishing B-70 Valkyrie: probrably lots more.
Refurbishing the one and only B-70 is out of the question and bringing
back planes in general seems like an expensive way to go. If there are
no current experimental planes that would be good for such things maybe
the USAF or NASA should think about making one, but it would cost a
fair chunck of change.
How about the concord?
Seems like it goes at 1,200 MPH or so and at something nice like 70,000 feet.
This should be a big improvement over the 600 MPH and 40,000 feet of a
B-52. Should increase the payload to orbit by 150 lbs or more and so be
worth around $1,500,000 per flight. I doubt Orbital Sciences Corp could
rent a concord for this purpose. Anyone know how much the concord sells for?
How many flights per year would we need to justify the payments on a
concord?
-- Vince
PS What about the kevlar towline stuff?
Ben Burch
presently unremembered) is shown a mechanically-pressurized suit from the
mid-1950's. This was an elastic pressure garment which used the skin as the
vapor barrier and which used skin evaporation for thermal regulation. It had
a separate oxygen pressurized helmet. No doubt the pressures in the helmet
were of the order of 3.5 psi to minimize leakage and the amount of mechanical
force required to keep the helmet mantlet gasket on the shoulders. This is
one of those really elegant ideas that one looks at sometimes, unable to
understand what, besides social inertia, killed it.
Oh yes, the fingers were encased in what looked like rubber finger cots.
- Ben Burch (bu...@quik07.enet.dec.com)
"Views expressed herein are not those of Digital Equipment Corporation."
Fraering Philip
o
o Philip Fraering :
o >A fully or partially reusable vehicle using RL-10 engines, similar to
o >Third Millenium Inc.'s _original_ design for the Space Van, and with
o >multiple stages, would probrably have a lower price.
o
o Sounds interesting. Can you tell us more about this?
o
o >So, in summary: please stop bugging Mary Shafer about which of the
o >experimental aircraft in her stable at Dryden will improve the
o >performance of a launcher that uses 325 Isp fuel when (although with
o >a little more difficulty) 450 Isp fuel (Hydrogen/Oxygen) could be used
o >instead. Think about it.
o >
o >Remember: The cost of developing Pegasus from point zero: $40 million.
o >Cost of refurbishing B-70 Valkyrie: probrably lots more.
o
o Part of the reason the Pegasus cost only $40 million to develop was that
o they used the simpler fuel.
o
o
Third Millenium Corp., also abbreviated as MMI, had been (and may still be)
seeking development money for a design for a mini-shuttle called the
"space van." The design was never frozen; one of the early ones involved a
vehicle that launched from a 747 which could either go into orbit itself on
the last gasp of fuel, with enough weight for one pilot and retrorocket fuel,
or could carry a space stage up to Mach 5 or so. The space stage could carry
3000 kg into orbit. The Space Van itself was recoverable; it had 6-8 RL-10
engines. The space stage had one, but it was not recoverable, except maybe
if the Space Van went up and recovered it. The details of recovering objects
with very small tugs, etc. have been covered extensively in the recent
postings on laser-launchings. Of course, the space stage could be refuelled,
or taken apart and the tankage used, ...
It should be noted that the RL-10 cryogenic engine is the oldest liquid
hydrogen engine ever used; it may have even been the first. (Anyone out
there have details?) I suspect that the first one may even have been shaped
using flint tools. (:-)"
Using it should be absurdly easy. It would even be cheaper than using
solid fuel due to the insurance savings: you can't abort a solid booster
very well. If something goes wrong, there goes the mission, or probrably
the vehicle.
The things with the winch or whip sound much more risky than changing to an
engine that has seen 20 years of reliable use. In fact, it sounds a lot like
what is called in the oilfield a "goat-roping exercise."
Winch launch has been used on low-speed gliders, but I doubt anything else.
Phil Fraering
dlbres10
Henry Spencer
Concorde, please. Not impossible, but Concorde is not built for dropping
things, and it would take quite a bit of work to fit it for the job and
test things out properly. (Proper separation of a dropped object at
supersonic speed is not to be taken for granted -- fighter designers work
fairly hard on this and test it at great length.)
A more fundamental problem is that it's an expensive bird to operate --
the current ones make money (yes, they do, they were subsidized once but
not any more) only by having very high fares -- and none of the existing
ones is for sale.
Edward V. Wright
>Third Millenium Corp., also abbreviated as MMI, had been (and may still be)
>seeking development money for a design for a mini-shuttle called the
>"space van." The design was never frozen; one of the early ones involved a
>vehicle that launched from a 747 which could either go into orbit itself on
>the last gasp of fuel, with enough weight for one pilot and retrorocket fuel,
>or could carry a space stage up to Mach 5 or so.
This version of the Space Van was for passenger, including tourist,
flights. The payload was actually one pilot and five passengers,
if memory serves me right.
>The space stage could carry
>3000 kg into orbit. The Space Van itself was recoverable; it had 6-8 RL-10
>engines. The space stage had one, but it was not recoverable, except maybe
>if the Space Van went up and recovered it.
There were, in fact, plans to do this. Only the engine module would have
been recovered, the Space Stage propellent tanks and payload fairing,
being cheap, would be expended. One Space Van mission could recover
several Space Stage propulsion packages.
>It should be noted that the RL-10 cryogenic engine is the oldest liquid
>hydrogen engine ever used; it may have even been the first.
It is also one of the most reliable engines ever built. It has been
used on the Centaur upper stage for more than 20 years without a single
inflight failure. Although not designed as a reuseable engine, its
ability to sustain multiple restarts and long firing life -- the qualities
you need in a reuseable engine -- have been demonstrated in static firings
under simulated space conditions.
Henry Spencer
>The only way that the Concorde shows a profit is that the acquisition
>costs was written off rather than amortized. It's a lot easier to make
>a profit on an airplane if someone gives you the airplane...
On the other hand, it's virtually impossible to make a profit on the
airplane if they insist on getting back all the development costs of a
very ambitious project by selling a production run of less than 20.
Given the impossibility of ever recovering the investment, giving the
things to the national airlines wasn't an unreasonable thing to do.
The cost situation isn't that dissimilar to what it would have been if
zillions of them had been sold -- they'd have purchase prices to repay
but maintenance would be quite a bit cheaper (getting spares made is
very costly for such a small fleet).
>What you want for the Pegasus launch vehicle is a good workhorse, with
>a large fleet for support, inexpensive to operate. You don't want a
>plane that's a bigger risk than the Pegasus.
This, on the other hand :-), I agree with. Using Concorde would have
to be a huge win to make it worthwhile. It would help, but not that much.
Tom Neff
it it doesn't sound so silly anymore.
What about launching Pegasus from a dirigible?
OK, you don't get as many initial MPH as from a Buff, but the aircraft's
speed is only a tiny fraction of what the rocket itself generates, so does
it matter that much? (Specifically, could you make up for it in rocket
performance given a dirigible launcher?)
In exchange for slowing down, you get INFINITE time to hang around in the
air and get ready for launch. And lots of space for a launch rack that's
more freely optimized for its job, instead of fitting into a streamlined
fuselage.
There do exist big LTA designs considered buildable if you had a reason.
The Soviets are supposedly going to start a big heavylifter for cargo
work, according to a recent AvWeek.
Just something to think about.
--
"We must never forget that if the war in Vietnam \ $ Tom Neff
is lost... the right of free speech will be X tn...@bfmny0.UU.NET
extinguished throughout the world." -- RN 10/27/65 $ \ uunet!bfmny0!tneff
Stephen Duncan
convinced to part with one. How much effect does the pod have on the
ability of an aircraft to go supersonic? I seem to remember hearing
that the Concorde could go about Mach 2.2. (An unmodified 747 or B-52
goes what, about Mach .7 to .8?)
Steve Duncan
dun...@rti.rti.org
Greg Wilkins
>>I am wondering wheter or not a human body exposed to void would explode,
>
>limited by other factors (e.g. how big the hole in the wall was), and the
>only significant hazard would be rupturing your eardrums if you had a cold
>or otherwise didn't get your ears depressurized properly. There is some
>cooling effect from evaporation of sweat, much as there is in air, but
>vacuum has no temperature and there is no reason why you would "rapidly
>freeze". And your skin is a good grade of leather, and does a good job
>(temporarily!) of holding in your body water.
>
>After ten minutes it would undoubtedly be different, but the only problem
>with a brief exposure to vacuum is inability to breathe.
>--
From Scuba diving experience, any time ambient pressure is halved, a person
is in danger of decompression sickness (The bends). I understand this is
why the shuttle crew must spend some time pre-breathing O2 before suiting
up for a "out-of-vehicle-experience!!!:-)".
Recompression alone will NOT cure the bends. Bubbles of gas formed in the
blood stream are compressed, but not removed by recompression. As for
damage to the brain/lungs/etc from stroke type injuries caused by
circulation blockage, biochemical changes in the blood,..... etc etc (lots
of nasty details deleted).
Recompression therapy for the bends often involves pressures higher than
those experience before the decompression, together with breathing pure
O2 (always dangerous, more so when pressure is involved).
May I suggest reading "Decompression in Depth - proceedings of the Seminar,
PADI, 1243 East Warner Ave, Santa Ana, CA 92705".
Decompression to vacuum is probably survivable -> But I doubt that it would
be so with out medical complications.
-gregw
Mary Shafer
soften in the heat.
In my opinion, Concorde is a bad launch aircraft, too. There are only
a few of them, they're obsolete, and they're expensive. Each of the
two airlines have one plane that they're cannibalizing for spares.
The only way that the Concorde shows a profit is that the acquisition
costs was written off rather than amortized. It's a lot easier to make
a profit on an airplane if someone gives you the airplane and that, in
bookkeeping terms, is what happened.
What you want for the Pegasus launch vehicle is a good workhorse, with
a large fleet for support, inexpensive to operate. You don't want a
plane that's a bigger risk than the Pegasus.
Mary Shafer
:In article <SHAFER.90A...@skipper.dfrf.nasa.gov> sha...@skipper.dfrf.nasa.gov (Mary Shafer) writes:
:>The only way that the Concorde shows a profit is that the acquisition
:>costs was written off rather than amortized. It's a lot easier to make
:>a profit on an airplane if someone gives you the airplane...
:On the other hand, it's virtually impossible to make a profit on the
:airplane if they insist on getting back all the development costs of a
:very ambitious project by selling a production run of less than 20.
:Given the impossibility of ever recovering the investment, giving the
:things to the national airlines wasn't an unreasonable thing to do.
:The cost situation isn't that dissimilar to what it would have been if
:zillions of them had been sold -- they'd have purchase prices to repay
:but maintenance would be quite a bit cheaper (getting spares made is
:very costly for such a small fleet).
I wasn't criticizing them for writing off the debt. Once the market
didn't prove out, the Concorde production run was obviously going to
be short and expensive. When I was working at Lockheed during the FAA
certification phase of the L-1011 Tristar they told us that the
company wouldn't start to make a profit until the breakeven airplane,
which was about number 200. There's no way that the Concorde even
approached the breakeven point.
I'll mention that the bookkeeping legerdemain was part of the UK
privatization drive and it was just as sensible as any other
accounting procedure is. However, I'll leave it as an exercise for
the reader to determine how sensible accounting is.
My point was that developing and operating limited-run or one-off
aircraft is expensive and difficult. The fact that British Airways
"makes a profit" on such an aircraft, the Concorde, is the result
of bookkeeping techniques. A small company like OSC (versus a
huge national airline) can't hide reality with these techniques.
Loren Carpenter
A 747 cruises at about .86 Mach. However, I recall a story from my days
at Boeing. In the 70's (and probably still) Boeing tried real hard to get
the USAF to buy 747's for cargo, tankers, ANYTHING. In the process, there
were a lot of demo flights for generals and other influential people.
One particular flight was accompanied by a friend of a friend. I don't
think I ever knew his responsibilites, but he had occasion to stand in the
cockpit doorway from time to time. So, out over eastern Washington state
(sagebrush and wheat for miles) this general says to the pilot, "Just how
fast does this thing go???". Well, the plane was essentially empty, and
they were cleared for silly maneuvers, so the pilot reached for the
throttles and pulled them back to takeoff power, then pushed the nose
down a few degrees. The noise level started to rise, from the aerodynamic
buffeting that you might expect. In fact, it got quite loud (loud enough
to scare the passengers, if this were a commercial flight.). Then all of
a sudden it got real quiet, except for the engine vibrations through the
structure. After they all finished laughing, the pilot backed off the
throttles and slowed the plane to normal cruise speed. My friend always
wondered how many tractor seats got wet that day.
Loren Carpenter
...ucbvax!pixar!loren
Bruce Dunn
The velocity imparted by launching Pegasus from a moving airplane and the
reduction in air drag by launching at altitude are not the only reasons for air
launching. Another major cause of increased payloads is that rockets have a
higher exhaust velocity in a vacuum than in air, and launching above much of
the earth's atmosphere gives a substantial performance improvement to the first
stage.
--
Bruce Dunn Vancouver, Canada a7...@mindlink.UUCP
Marcus Hall
Fraering Philip:
]Remember: The cost of developing Pegasus from point zero: $40 million.
]Cost of refurbishing B-70 Valkyrie: probrably lots more.
Vincent Cate:
>.... Remember, and increase of 300 lbs worth of payload
>at $10,000/lb is worth $3,000,000. There are no planes that cost that
>much per flight.
Actually, I've heard that the XB-70 cost about $10,000,000 per flight. This
was counting all the development costs, but still, it was quite expensive.
I don't know what the actual operational costs were, presumably they were
something close to reasonable since it was intended to be an operational
plane.
>I did not really mean to suggest that we use the Valkyrie. I just knew
>that 25 years ago we had a fast big plane and wondered if we had one
>today. I see that we do not. Oh well.
Yea, 25 years ago we had alot of things (Saturn production, etc.) Rather
depressing to see what's become of it all..
marcus hall
bxr...@csc.anu.oz
Why not use the B1-B? While not as fast as the XB-70, it is quite fast
at altitude (about Mach 2 if my memory serves me) and it should be able to
carry a Pegasus without too much trouble. The other alternative might be to
hire the Soviet's to do it for you with a "Blackjack" ;-)
Brian Ross
Walt Leipold
combination, why not use your LTA capability to get Pegasus up to about
80,000' and drop the silly thing? By the time it gets down to the
altitude that the B-52 launches it from (50k feet?), it should be going
at least Mach 0.7 or so, and you can fly the original flight profile
from there. If LTA is really a cheaper way to get payloads to high
altitudes, then you can get identical performance at a lower cost.
--
"As long as you've lit one candle, Walt Leipold
you're allowed to curse the darkness." (leipolw%es...@dupont.com)
--
--
The UUCP Mailer
David Smith
>"As long as you've lit one candle, Walt Leipold
>you're allowed to curse the darkness." (leipolw%es...@dupont.com)
Curse the candle, let's have the night sky!
--
David R. Smith, HP Labs
dsm...@hplabs.hp.com
(415) 857-7898