henry@utzoo.uucp (Henry Spencer) (06/17/88)
[As you have probably noticed, I am behind on AW&ST summaries. I will
try and catch up a bit before I leave for Usenix. However, this one
won't wait. The June 6 issue just arrived, and the lead story is the
best news in years. So here's a special out-of-sequence report.]
New launcher: Pegasus, a winged three-stage design that will be air-
launched from a B-52. It's a joint effort of Orbital Sciences and
Hercules, with Rutan building the wing. Payload is 600lb into low
polar orbit, 900 into low equatorial orbit.
Now the GOOD news... Pegasus is 100% private, although the first customer
is DARPA. Total funding is $40-45M, about a third of it already spent.
It has been underway about one year, they are already bending metal on
the first one, and it flies NEXT YEAR! There is already a lineup of
customers. Cost to orbit will be half or less that of similar-sized
payloads on existing launchers.
[At **LAST**, a launcher being built by sensible people! Note the modest
size, the rapid schedule -- two years from startup to launch -- and the
miniscule budget. Not to mention the lack of any attempt to force the
taxpayers to fund it. This is how commercial launchers OUGHT to be done;
thank all the gods that somebody had the guts to try doing it right!]
DARPA is in the final stages of becoming the first customer, with a
contract expected to be signed next week. The nature of the payload has
not been released, but it is thought to be a small experimental comsat.
Launch is set for July 1989. DARPA is buying launch services only, no
funding for development is involved.
Second launch will probably be another DoD payload from "a different
agency" [betcha it's SDI] in Oct 1989. A NASA science payload is a
candidate for number three in Dec 1989.
OSC and Hercules are splitting the development cost 50-50 and will split
profits the same way. Funding is entirely from internal resources and no
outside capital is involved. Contractors have been picked, staff has
been hired, parts are being built.
Pegasus uses three new-design Hercules solid motors. Use of existing
motors was considered, but new motors looked like a better bet. Cases
are graphite composite, as is the wing, being developed by Burt Rutan.
The thing is 49 feet long with a wing span of 22 feet, total weight
40klbs. These numbers are almost identical to those of the X-15, and
the X-15's old B-52 will be the initial carrier aircraft. Gordon
Fullerton, NASA research pilot and former astronaut (two shuttle missions)
will command the B-52 for the first launch. Pegasus will pay NASA for
the use of the aircraft for commercial launches. Up to 15 launches
might be made from the NASA B-52, after which transition to a commercial
heavy transport is expected. The aircraft has been picked but its
identity is proprietary as yet.
[Now why would they keep the identity of the aircraft secret? I mean,
the 747 is the obvious choice. Unless... you don't suppose they're
going to use an Airbus A340?!? Congress will be livid.]
Drop will be at 40,000 ft. The first stage will light and fly a shallow
wing-borne trajectory to Mach 8.7 at 208,000 ft. The wing is on the
first stage, so the second and third stages fly more conventional
upper-stage trajectories into orbit.
The first launch will be into polar orbit, starting offshore from
Vandenberg. Using air launch, of course, launch site and direction are
pretty much arbitrary. It also means that Pegasus does not have to
fight for access to launch facilities. [And they don't have to deal
with the government, or mortgage their mothers to pay for insurance
against launch-site damage.]
Pegasus develoment is considered 50% complete; OSC+Hercules will hold
a major engineering review this week. Late this month they will start
using Ames's supercomputers for aerodynamic simulation -- Pegasus will
not be wind-tunnel tested. They are already working with Ames people.
[Eugene? You involved in this?]
OSC+Hercules expect to price a Pegasus launch at under $10M. They
forecast 10-12 per year and believe that it can support itself with
half that. Breakeven will be reached after 16-18 launches, and with
luck this will be two or three years after the first flight. Lots
of people are interested, and a relatively diverse mix of customers
is likely. This should give a fairly stable customer base.
Pegasus's payload shroud is relatively large for the payload mass, 72in
long by 46in wide, permitting a wide range of payload designs. Pegasus
is being built for minimum prelaunch handling; eventually it is hoped
that only 6-7 technicians will be needed for final assembly and launch.
This will help costs a *lot*. Minimal ground hardware will be needed;
no cranes.
Also of interest, especially to Ames, is hypersonic flight testing at
high altitudes and Mach numbers. The early Pegasus flights will carry
quite a bit of Ames instrumentation to gather data relevant to the
Aerospace Plane. 1500 lbs could be carried on a dedicated suborbital
flight.
Air launch turns out to give a 10-15% reduction in the necessary delta-V.
The forward speed of the aircraft helps a bit. Launching at 40,000 ft
helps much more: it reduces drag, reduces stress on the structure,
reduces aerodynamic heating, reduces pressure loss in the exhaust,
and permits a higher expansion ratio in the first-stage nozzle. The
horizontal launch and the wing permit flying a much flatter and more
efficient trajectory, and also greatly reduce the angle of attack
needed for an air launch (a wingless air-launched rocket would have
to make a sharp turn upward). The excellent supersonic wing (L:D 4:1)
gives better performance than a similar weight of rocket fuel. (The
wing will actually start to char just before first-stage burnout, but
it doesn't matter since Pegasus is not reusable.) The net result is
twice the payload mass fraction of a ground-launched booster.
[Like I said, this is the best news in years. I hope OSC and Hercules
make a bundle from this: they deserve it.]
[Hmmm... 900 pounds, 42 inches. Kind of tight, and the upper-stage
accelerations look uncomfortably high, but I bet you could man-rate it
if you really tried.]
--
Man is the best computer we can | Henry Spencer @ U of Toronto Zoology
put aboard a spacecraft. --Von Braun | {ihnp4,decvax,uunet!mnetor}!utzoo!henryroy@phri.UUCP (Roy Smith) (06/18/88)
henry@utzoo.uucp (Henry Spencer) writes: > Pegasus, a winged three-stage design that will be air-launched from a B-52. > [...] Payload is 600lb into low polar orbit, 900 into low equatorial orbit. For the benefit of us interested-but-ignorant observers, can you give me some idea of how useful a 600-900 pound (still no metric!) payload is? What does a typical commsat weigh, for example? Or a typical package of scientific instrumentation? Or (God forbid), a typical military payload (warhead, spysat, whatever). Is there even such a thing as "typical"? Would such a delivery system be useful for making small emergency shipments to a permanent space station ("Houston, we, uh, seem to have loaded our camera wrong and wasted all our film; think you could Pegasus up another few rolls before this comet goes out of range?"). Sounds like putting one of these up might be a lot faster than waiting for the next scheduled shuttle. -- Roy Smith, System Administrator Public Health Research Institute 455 First Avenue, New York, NY 10016 {allegra,philabs,cmcl2,rutgers}!phri!roy -or- phri!roy@uunet.uu.net
web@garnet.berkeley.edu (06/19/88)
In article <1988Jun17.053132.5314@utzoo.uucp>, henry@utzoo (Henry Spencer) writes: > The June 6 issue just arrived, and the lead story is the >best news in years. So here's a special out-of-sequence report.] > >New launcher: Pegasus, a winged three-stage design that will be air- >launched from a B-52. It's a joint effort of Orbital Sciences and >Hercules, with Rutan building the wing. Payload is 600lb into low >polar orbit, 900 into low equatorial orbit. > >Now the GOOD news... Pegasus is 100% private, although the first customer >is DARPA. Total funding is $40-45M, about a third of it already spent. >It has been underway about one year, they are already bending metal on >the first one, and it flies NEXT YEAR! There is already a lineup of >customers. Cost to orbit will be half or less that of similar-sized >payloads on existing launchers. > Private development is not new-- Space Services Inc. of Houston has designed, built and *flown* the Conestoga using private funds. And they are offering their launchers to DARPA on a strictly commercial basis. Furthermore, it is an exaggerated claim that the $10M launch price (or is it expected launch price) of the Pegasus is half that of the competition. If DARPA commits to buying launches on a vehicle which is still in the development stage, how is that significantly different from them paying for development? What happens when there are cost overruns and production delays? The article also raises questions about possible hidden subsidies: How much are OSC and Hercules paying for use of the NASA B52? How much are they paying for computing at Ames? There are certainly advantages to a B52-launched vehicle, and Henry mentioned several. But there are still large obstacles to be overcome. Hercules and OSC claim that they will develop, build and certify not one, not two, but three new motors with $45M, and in one year. I hope so! How is Hercules doing on its more luxuriously funded motor development programs? One of the more important aspects of this article is the tense. The Pegasus will cost less than $10M per launch. The Pegasus will fly next summer, even though none of the three motors has yet been built. The Pegasus will only cost $45M to develop. The Pegasus will succeed because the project needs only five to six missions annually to remain viable. Hercules and OSC have far to go before this project amounts to much more than the inflated claims of a marketing campaign. I sincerely hope they succeed, and wish them luck. -- --
henry@utzoo.uucp (Henry Spencer) (06/20/88)
> ...some idea of how useful a 600-900 pound (still no metric!) payload is? It's not big enough for most recent payloads, which have tended heavily toward the pile-everything-into-one-huge-lump school of design. However, many people feel that this tendency has gone much too far, and that there would be many benefits from going back to small single-mission satellites for a lot of jobs. 600-900 lbs is lots for *one* scientific experiment plus support equipment, and is enough to be useful for things like communications and espionage if you are willing to design the equipment to fit. Personally, I suspect you could make money on even smaller payloads if you offered cheap, frequent, short-notice, low-hassle launches. > Would such a delivery system be useful for making small emergency > shipments to a permanent space station... Yes, assuming a solution to the unmanned-rendezvous-and-docking issue. (The OMV now under development might suffice.) -- Man is the best computer we can | Henry Spencer @ U of Toronto Zoology put aboard a spacecraft. --Von Braun | {ihnp4,decvax,uunet!mnetor}!utzoo!henry
karn@thumper.bellcore.com (Phil R. Karn) (06/22/88)
> Man is the best computer we can put aboard a spacecraft. --Von Braun
Last week's successful Ariane-4 launch put AMSAT Phase 3-C and two other
satellites into the following orbit:
perigee 221 km (nominal: 220 km)
apogee 36,359 km (nominal: 36,294 km)
inclination 10.01 deg (nominal: 10 deg)
I'd like to see some fighter jock/astronaut do as well by flying a
launch manually. Perhaps you should limit the scope of this statement
somewhat.
Von Braun, of all people, should have known better. But he was not
exactly known as one who always placed high ethical standards above
doing and saying whatever was required to get funding from whomever he
happened to be working for at the time.
Philtodd@uop.edu (Dr. Nethack is back) (06/22/88)
In article <1176@thumper.bellcore.com>, karn@thumper.bellcore.com (Phil R. Karn) writes: > > Man is the best computer we can put aboard a spacecraft. --Von Braun > > Last week's successful Ariane-4 launch put AMSAT Phase 3-C and two other > satellites into the following orbit: > > perigee 221 km (nominal: 220 km) > apogee 36,359 km (nominal: 36,294 km) > inclination 10.01 deg (nominal: 10 deg) > > I'd like to see some fighter jock/astronaut do as well by flying a > launch manually. Perhaps you should limit the scope of this statement > somewhat. Computer operations can, at times be more efficient, perhaps his claim was more philosophic.. when a computer breaks, or malfunctions, or (at times) performs its task, it still is not capable of the intuitive things a human is. And there is the kicker. Has nothing to do with jockness. And everything to do with improvisation.. Computers *helped* bring back Apollo 13, as a tool to devise various probabilties, etc. But Men brought her home, both ground crew, and otherwise. Now are you going to say, she should have never flown? That would be as absurd as saying you can tell me whenever a jet should never take to the skies. You can't predict everything...at least a human is flexible enough to *try* different things. Voyager's computers had to be re-tweaked from the ground due to damage, could it do that itself? (Maybe we are finally getting close enough in technology for self corrections but there is still the cause and effect of needing a human in the chain somewhere.. if only to look at the images!)
rhorn@infinet.UUCP (Rob Horn) (06/24/88)
In article <3361@phri.UUCP> roy@phri.UUCP (Roy Smith) writes: >henry@utzoo.uucp (Henry Spencer) writes: >> Pegasus, a winged three-stage design that will be air-launched from a B-52. >> [...] Payload is 600lb into low polar orbit, 900 into low equatorial orbit. > >What does a typical commsat weigh, for example? Depends on the type. Geosynch tend to be heavier. 2000kg and up. One major consideration is power supply and another is fuel for station keeping. BUT, low earth orbit fit easily in this. The latest AMSAT (Up and WORKING !!!! yeah) weights 140 kg. This kind of satellite supports packet radio techniques. DARPA has funded paper studies of a ``cloud'' of these as an alternative to geosynch. > Or a typical package of >scientific instrumentation? I've gotten data from a 10kg satellite. But there is no typical. > Or (God forbid), a typical military payload >(warhead, spysat, whatever). Spysats are HUGE, partly because optics are huge and partly because they want maneuvering capability (fuel+motor) and partly for long life. But a lot of this is the result of the present difficulty in making a decision to launch on a day's notice. (Optics being the exception.) -- Rob Horn UUCP: ...harvard!adelie!infinet!rhorn ...ulowell!infinet!rhorn, ..decvax!infinet!rhorn Snail: Infinet, 40 High St., North Andover, MA
fiddler%concertina@Sun.COM (Steve Hix) (06/28/88)
[ Description of Pegasus, and accompanying comments, deleted. ] Best news I've heard in years. Hope the responsible parties get filthy rich for doing it. It's no more than they deserve.