Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT_ZIP/spacedig/V13_4/V13_477.ZIP/V13_477

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Subject: SPACE Digest V13 #477

SPACE Digest                                     Volume 13 : Issue 477

Today's Topics:
             Re:  Saturn V vs ALS
               Re: Saturn V and the ALS
               Re: Saturn V and the ALS
                Galileo works?
             Re: Saturn V vs. ALS
            space news from March 11 AW&ST
             Re: Galileo Solution
             Re: Saturn V vs. ALS
               Another Galileo Sulution

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Date: 28 Apr 91 07:33:27 GMT
From: cs.utexas.edu!swrinde!sdd.hp.com!uakari.primate.wisc.edu!dali.cs.montana.edu!milton!hardy.u.washington.edu![e-mail]  (Brett Vansteenwyk)
Subject: Re:  Saturn V vs ALS

Consider the following development pedigree:
  Saturn V:  Return to heavy lift capability
  Saturn VI:  Using what we learned in the '70s and '80s to lighten/improve
        the basic Saturn V design
  Saturn VII:  A Saturn VI modified so that the first stage is now a flyback
        booster (the Boeing proposal).
The end result (or even a Saturn VI) would probably contain most of the
desirable features of modern boosters, including one the "modern" ones don't
have:  it will be reliable.  Making a program where you first try to get
operational with a reasonable existing design, then incrementally improve
along what would seem to be a well-marked trail, would keep you improving
without forcing you to go through no-op phases that last a year or more.
You will improve while staying operational--and staying operational seems to
be a feature that we have come to appreciate more and more (at least, our
gov't opinion leaders are giving more lip service to it).  The development
trail would be longer, but I think that a flyback Saturn V would have some
technical advantages over the ALS, and in the meantime we would have access
to orbit at a reasonable cost.

    I do have one concern--and I admit I have not read all the postings on
this subject, so I do not know if this was covered--what would the Saturn V
based cargo booster configuration look like?  I could see a case for only
keeping the first two stages since they are sufficient by themselves for
getting into orbit.  Unfortunately, if memory serves me, all the smarts of
this rocket are in the third stage.  Would there be a problem in putting them
in a section of the payload canister?  Would a third stage the size of the
original Saturn V third stage be justified even for geosynchronous orbit
delivery?

                    ---Brett Van Steenwyk

------------------------------

Date: 26 Apr 91 15:06:41 GMT
From: agate!bionet!uwm.edu!caen!uakari.primate.wisc.edu!crdgw1!gecrdvm1![e-mail]
Subject: Re: Saturn V and the ALS

In article <[e-mail]>,
[e-mail] (Glenn A. Serre) says:
>
>Indeed, two of ALS goals are to be big and cheap. However,
>1) Current ALS designs are cheap only with high launch rates.
>2) ALS will be very expensive and time-consuming to develop and build;
>starting
>over if it turns out not to be cheap doesn't seem very likely.  Consider the
>shuttle.  One of its design goals was to be cheap.  It is not cheap, and we
>haven't started over, we've built another one.
>3) Big and Cheap are only two of ALS design goals.  Henry pointed out earlier
Maybe the whole trick is to have as an actual goal of being cheap and or
big, rather than a "research" program sold on false promises (cheap).
methinks that if NASA/US Gov't really wanted a cheap launcher it could
build one quite easily, but then there would be no excuse for further
research.  Besides which, wouldn't the rest of the launch companies
go belly up if company X blows them away with a cheap,reliable launcher?

------------------------------

Date: 26 Apr 91 14:16:08 GMT
From: crdgw1!gecrdvm1![e-mail]
Subject: Re: Saturn V and the ALS

In article <[e-mail]>,
[e-mail] (Glenn A. Serre) says:
>
>
>   > *not* have to debug the design significantly.  For example, we know the
>   > engines run reliably without serious combustion instability... and that
>   > is several years' development bypassed right there.
>
>   BUT, engines could be made that burn less fuel and therefore lift
>   even more to orbit.  Maybe rocketdyne could modify the F-1 to
>   bring it up to date.
>
>This is how we got the SSMEs.  Increasing performance does not decrease
>cost, nor does it increase reliability (neccessarily).  The Saturn V could
It is my understanding that the SSME and the F-1 are two different beasts
a   main difference being fuels. Isn't there alsoa difference in the
method of fuel delivery/combustion in which the SSME opted for the
more risky/tempermental approach (sort o like the difference in a
rotary vs piston engine?).  Have to cry here for the experts'
explaination, and advice: could the F-1 be improved easily, either
performance or manufacturability, or is it fine the way it is?

>lift plenty of weight (mass, whatever) to orbit: 265,000 pounds.
in light of several people asserting that it is the cost of the
payload rather than the launcher which defines current launch rate,
would a big booster by itself more expensive (but cheaper/kg) reduce
overall launch costs by eliminating the need for expensive miniaturi-
zation of the payload?


>
>
>and they worked reliably.  Maybe if we had been building and using F-1s since
>the Apollo days, they would now be somewhat improved, but we scrapped the
>tried and true Saturn for the complex, high-performance Shuttle and its
>SSMEs.
Ah, the wisdom of hindsight. It's about as useful as ifsight. Like, IF
the shuttle had been done right (yeah I know I'm in a minority in saying
the shuttle could have been built properly.  I'm not saying it was the
best of ideas, or that its promises were realistic, but I believe that
a shuttle could have been built that was more up to spec) there would
have been no regret about scrapping Saturn.  or IF politics and
porkbarreling weren't part of the space program we might actually be
getting our money's worth.

------------------------------

Date: 28 Apr 91 14:35:58 GMT
From: bionet!uwm.edu!wuarchive!rex!rouge![e-mail]  (Fraering Philip)
Subject: Galileo works?

I heard from a friend over here (who I guess heard it on the news)
that the moment of inertia for the Galileo probe is totally in
agreement with a correctly-performed antenna deployment. In short, the
antenna deployed, but the sensor doesn't know (sound familiar to
anyone?).

Anyway, although more asteroid missions, in my humble opinion, might
be a good thing, many thousands of people worked very hard on Galileo
for the express purpose of looking at Jupiter and its satellites. It
might even be optimized to the task. Moving Galileo to look at
asteroids would probrably waste a great deal of the instruments for
analyzing the space enviornment unless asteroids have ionospheres and
magnetic fields.

--
Phil Fraering
[e-mail]
Joke going around: "How many country music singers does it take to
change a light bulb? Four. One to change the bulb, and three to sing
about the old one."

------------------------------

Date: 28 Apr 91 14:48:15 GMT
From: agate!bionet!uwm.edu!wuarchive!rex!rouge![e-mail]  (Fraering Philip)
Subject: Re: Saturn V vs. ALS

In article <[e-mail]> [e-mail] (Henry Spencer) writes:

>It is.  Now for the hard part of the assignment:  name three more such
>investments, to justify the plural in "companies".  The OSC/Hercules
>Pegasus effort is a rare exception, not the rule.

Space related: How about the decision by General Dynamics to go ahead
with building the new Atlas-Centaur production line without enough
orders in place already to pay for it?

The proposed Iridium system?

Aerospace related: the decision by Northrup to develop the F-20? They
lost a billion dollars or so on that long-term investment thanks to
the fact that noone would buy it unless the Air Force bought it, and
the Air Force likes the F-16 more, even though the plane had to be
totally re-done to get the contract the two planes were competing
for...

777? The recent flight-test program for the 747-400, which (or so I
gather) went above and beyond the call of duty in testing overloaded
planes taking off and landing, among other things?

--
Phil Fraering
[e-mail]
Joke going around: "How many country music singers does it take to
change a light bulb? Four. One to change the bulb, and three to sing
about the old one."

------------------------------

Date: 29 Apr 91 01:10:39 GMT
From: bonnie.concordia.ca!news-server.csri.toronto.edu!utzoo![e-mail]  (Henry Spencer)
Subject: space news from March 11 AW&ST

NASA's Precision Segmented Reflector program, aimed at mirrors for space
astronomy, will terminate at the end of FY91.  The excuse offered is that
advances in adaptive optics etc. require some rethinking.

The U of Houston Wake Shield project, intended to fly on the end of the
orbiter's arm, is being upgraded to a free-flier, separated from the
shuttle for a few days during a mission.  The intent of the project is
to provide an ultra-clean environment in the wake of a conical shield,
and concerns about contamination from the orbiter have arisen.

NASA decides to launch Atlantis despite minor hinge cracks.  The cracks
found in Atlantis are actually closer to being scratches, and are not as
serious as the ones in Discovery and Columbia.

The Ariane mission delayed due to third-stage worries flies; no problem.

Launch dates for Cassini and CRAF have been swapped to give CRAF more
development time and weight margin.  Cassini goes in Nov 1995, CRAF in
Feb 1996.  The changes also include a Venus gravity assist for CRAF,
which will add eight months to the flight time but increase payload
and provide better fallback launch windows if CRAF can't make Feb 1996.

NASA engineer at Reston, asked by visitor why his office and adjacent
hallways lack models, photos, paintings of Fred, comments:  "Are you
kidding me?  This is the Space Station Office.  We don't know anything
about hardware here!"  [Meant humorously, but oh so appropriate...]

OSC to get two new NASA contracts:  seven Pegasus launches (plus options
on three more) for Goddard's Small Explorer series, starting 1993 and
running two per year, and five years of data from OSC's proposed SeaStar
commercial remote-sensing satellite, starting in Oct 1993.  The latter
is noteworthy as the first government purchase of such data from a fully
private venture.

DARA (the German space agency) recommends cutting the size of the Columbus
lab for Fred by a factor of two, mostly to cut costs but also to permit a
fully-equipped launch.  "If NASA is going to reduce their space station,
I think we have the right to reduce ours as well."  The resulting module
will be about the size of Spacelab.  The change would also help keep
Columbus logistic support within its current allotment of shuttle space.
NASA has not reacted officially, but Lenoir has said in the past that the
NASA changes might well spark changes in the foreign modules, and that
the US:foreign interfaces remain unchanged and the impact thus is minimal.

ESA has also asked NASA whether the Columbus man-tended free-flyer can be
serviced by the shuttle rather than by docking to Fred.  This would be
cheaper, but another concern is that docking the free-flyer to the station
will be trickier with the more closely-spaced solar arrays of the new
Fred design.

DARA also thinks that the man-tended free-flyer and Hermes should get a
program stretch, as both funding and manpower are tight for doing them,
the Columbus Fred module, and Ariane 5 simultaneously.

Arianespace is proposing to boost the performance of Ariane 5 [again!]
because Hermes keeps gaining weight.
--
And the bean-counter replied,           | Henry Spencer @ U of Toronto Zoology
"beans are more important".             |  [e-mail]  utzoo!henry

------------------------------

Date: 29 Apr 91 04:20:23 GMT
From: agate!lightning.Berkeley.EDU![e-mail]  (Frank Crary)
Subject: Re: Galileo Solution

In article <[e-mail]> [e-mail] (Paul Dietz) writes:
>Perhaps a more sensible approach would be to jettison the reentry
>probe, change the second gravity assist and salvage some science by
>abandoning Jupiter and converting to a multiple asteroid flyby
>mission.  It could repeatedly swing by earth and/or mars to be
>directed onto flybys of new asteroids.  With luck, we could get
>pictures of half a dozen or so, with the data from each encounter
>played back over the low gain antenna at the next flyby of earth.
While Galileo's scientific return from Jupiter would be much less if its
antenna can not be fixed, that does not mean it will return no data at all.

Also, Galileo's instruments are not intended for asteroid fly-bys. Since
they are on the way, Galileo is looking at two of them, but that does not
make Galileo a good platform for this work.

In addition, the Jovian atmospheric probe could operate at 100%, even with
out a high gain antenna on the orbiter. The orbiter could store the probe's
data and slowly send it back to Earth.

Even if the high-gain antenna cannot be deployed (why are you assming this
by the way), Galileo would, in my mind, still be more usefull as a partially
successful Juptier mission, instead of an improvised asteroid observer.

                                           Frank Crary
                       UC Berkeley

------------------------------

Date: 29 Apr 91 04:09:30 GMT
From: agate!lightning.Berkeley.EDU![e-mail]  (Frank Crary)
Subject: Re: Saturn V vs. ALS

In article <[e-mail]> [e-mail] (Richard Caley) writes:
>The shuttle is really only a first stage and given that they won't use
>a decent second stage for safety reasons, it might be nice to have
>something bigger.
>For instance, how long would Galleleo have taken to get to Jupiter if
>launched on something with an engine under it? Would it be so much
>more expensive when things like the ground support for all that time
>are costed in?

Yes, if Galileo had been launched on a liquid fuel upper stage, it
would get to Jupiter in only a fraction of the time it will actually
take. But this is an issue of crew (and orbiter) safty, not of payload
size. The shuttle could (if one wanted to take the risk) have sent
Galileo on a direct transfer. An unmanned rocket only slightly larger
than a Titan could have. Such a launch would not have required a heavy
lift launch vehicle.
>Besides, there is nothing sacred about one payload per rocket. If you
>have reasonable reliability, put two or three on it and have some
>capacity left to be able to design heavier, cheaper payloads.

While it is possible to launch several payloads on a single vehicle,
this is not always possible. All of the launched payloads must want to
go into more or less the same orbit. The builders must have all the
payloads ready for launch at the same time (unless one company is
willing to wait, and delay their launch for the benifit of another.)

These things can be done, but you should not count on them when figuring
launch costs. In reality, about half of the time, the launcher will
have only a single payload, even if it is only half the maximum launchable
mass.

                       Frank Crary
                       UC Berkeley

------------------------------

Date: Sun, 28 Apr 1991 18:16 CDT
From: [e-mail]
Subject: Another Galileo Sulution

Although putting a communications relay satellite in orbit around Jupiter
is a good idea, one must remember that Jupiter's position changes during
it's year, sometimes making it even further away from Galileo than Earth
would be.

Another possibility would be to launch a relay station into a trajectory
aimed directly at Galileo, thus the relative position between it and
Galileo remain unchanged. Relay-1 can then take on the task of tracking
Earth. Later, as Relay-1 gets far enough away from Earth, Relay-2 can
be launched to follow behind Relay-1 making it theoretically possible to
follow Galileo as long as we keep launching relay probes.

This approach would be ideal for following either Voyager 1 or 2, since
both are far enough away from here to make their 22 watt signals increasing
difficult and unreliable to receive.

Just how much would it cost to design, build, launch and maintain a probe
who's sole purpose would be to follow another probe, relaying transmissions
from it to Earth (or another relay in the chain) and back again? Just
how much payback would there be for such a simple probe if we are able to
collect scientific data from increasing distances away from the Sun's
influence, possible even as far away as the Oort cloud and further?

As long as we are hypothetically sending another probe to act as relay to
the first, we need to remember that the original satellites are going
to run out of power someday. If each successive probe were fitted with it's
own set of scientific measuring instruments, as the lead probe was finally
shut down the next probe could be "powered up" so to speak to take over
the responsibility of the mission.

Any thoughts on this approach? Has this already been considered by JPL
personnel? I would think that with the advances in our technology since
the original Voyager probes were launched, fitting a new satellite to
perform the basic task of relay station (plus having a good compliment
it's own scietific equipment) would mae for a smaller, more cost-effective
probe that could bring about a new level of scietific understanding of
the extended solar environment.

Robert Brown
[e-mail]

------------------------------

End of SPACE Digest V13 #477
*******************