Space & Astronomy/Space and Astronomy (October 1993).iso/mac/TEXT/SPACEDIG/V12_5/V12_562.TXT

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Subject: SPACE Digest V12 #562

SPACE Digest                                     Volume 12 : Issue 562

Today's Topics:
          Re: CRAF/Cassini Update - 11/09/90
            Re: sci.space or talk.origins?
               Magellan News Conference
        Re: Reliability and Insurance (2 of 3)
               Re: New Shuttle Engines
             Pity The Much Abused Shuttle
           Re: Pity The Much Abused Shuttle
             Re: LNLL Inflatable Stations
          Re: CRAF/Cassini Update - 11/09/90

Administrivia:

    Submissions to the SPACE Digest/sci.space should be mailed to
  [e-mail].  Other mail, esp. [un]subscription notices,
  should be sent to [e-mail], or, if urgent, to
             [e-mail]

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

Date: 14 Nov 90 17:09:03 GMT
From: usc!wuarchive!rex!rouge![e-mail]  (Fraering Philip)
Subject: Re: CRAF/Cassini Update - 11/09/90

Hold on a sec. I thought the Viking lander did have an RTG.

Phil

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

Date: 14 Nov 90 17:02:26 GMT
From: eagle![e-mail]  (Ronald E. Graham)
Subject: Re: sci.space or talk.origins?

In article <[e-mail]>, [e-mail] (Gary Coffman) writes...

[a bunch of stuff that belongs in e-mail...and I would have responded
there if my mailer could reach the original poster...]

>I've got to ask what a creationist with this unscientific attitude is doing
>in a sci group or for that matter receiving my tax dollars at a public
>scientific institution.

Doing my job.  Which is all you should be concerned with.

The subject of this guy's posting didn't even rate talk.origins, IMPO.

RG

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

Date: 14 Nov 90 22:02:07 GMT
From: usc!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov![e-mail]  (Ron Baalke)
Subject: Magellan News Conference

MAGELLAN NEWS CONFERENCE SCHEDULED

     There will be a Magellan mission news conference at the Jet
Propulsion Laboratory's von Karman Auditorium at 1 p.m. EST,
Friday, Nov. 16.  Speakers will discuss spacecraft status and
recent science results.

     Speakers will include Magellan Project Manager Anthony
Spear, Project Scientist Dr. Stephen Saunders, Drs. Gordon
Pettengill and Sean Solomon of the Massachusetts Institute of
Technology and Dr. Ray Arvidson of Washington University, St.
Louis.  New radar images of the Venus surface and a new 3-D video
will be shown.

     The news conference will be carried on NASA Select TV,
Satcom F2R, transponder 13, at 72 degrees west longitude, 3960.0
MHz, audio 6.8 MHz, with two-way question and answer
capability.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|
     | | | |  __ \ /| | | |      Ron Baalke         | [e-mail]
  ___| | | | |__) |/  | | |___   Jet Propulsion Lab | [e-mail]
 /___| | | |  ___/    | |/__ /|  M/S 301-355        |
 |_____|/  |_|/       |_____|/   Pasadena, CA 91109 |

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

Date: 13 Nov 90 03:40:15 GMT
From: usc!elroy.jpl.nasa.gov!zardoz.cpd.com!dhw68k!ofa123![e-mail]  (Wales Larrison)
Subject: Re: Reliability and Insurance (2 of 3)


    However, this does pose some interesting questions.  If, as you
say, the Delta HLV design is 7 Deltas strapped together, does this
not imply the reliability to be .98^7 = .86?  Also, looking at the
historical data shows that a significant design change to a launcher
typically results in a pattern of failure for a few years (shown in
Delta and Scout upgrades, and in the little bit of data I have on
Titan history).  How do we avoid the "infant morality" for a major
design change to a HLV?
    For discussion sakes, lets say .90 for the new, untested HLV,
and .98 from the shuttle.
   2) The difference in launch costs.   I will accept the Shuttle is
never get the economies of scale per individual launch available in
a HLV.  So the price of an individual shuttle launch will be always
higher ($/lb) than a HLV.  However, if we can increase the shuttle
annual flight rate from 4 to the planned 12, then the cost is
reduced by $2.3 B.
     Similarly, your HLV costs can be claimed as very opimistic. If,
LLNL is going to pay for a Space Station to completely recover the
development and financing costs for a HLV, and there is no long-
term recurring market, I think the cost could be increased.  Any
problems with early system reliability, delivery schedule,
government funding lines (leading to program stretch-out), technical
problems with the LLNL station, or the HLV delivery schedules would
increase its launch costs.
    Again, for discussion purposes, let us propose increasing the
HLV cost by 30% (at least!) for these considerations, and showing
the shuttle costs at a 12 per year flight rate.  $0.195B vs $1.170B.
   3) Engineering for assembly in orbit.  I would assume the
provisions needed to assemble something on orbit are the connections
be simple and very easy to do/undo via EVA.  However, aren't these
the same connections needed if the Space Station can be maintained
on orbit by EVA?  For example, if one of the LLNL modules were to be
damaged beyond repair by orbital debris, it would necessarily have
to have these EVA dis-assembly provisions, so the module could be
unhooked and a new one hooked in.  I would rate this as a wash,
between the two.
    Combining all this, gives a set of revised numbers...

Item            HLV          Shuttle
Payload         $22.5  B       $22.5   B
Insurance       $ 2.250        $ 0.450
Launch cost     $ 0.195        $ 1.175
EVA             $ 0.0          $ 0.002
Engineering     $ 0.0          $ 0.0       Same between the two
                --------       ---------
                 24.945         24.017
     Which has now reversed.... I would say the most sensitive part
of this calculation is reliability since Shuttle total costs come
out cheaper is HLV reliability is .94 or less (shuttle at .98).
Based upon the historical patterns for launch vehicle development,
this might be a reasonable bet.

     Anyway, I think we've beat this subject to death.  Can we agree
to disagree on this?  My opinion is that we need a HLV capability,
and I think it would make sense to apply such to any Space Station
program - after a good test period (10-20 flights).  I'm just not as
hard over on killing our current programs in favor of untested new
programs - without a much better examination of what this entails.
But I support activities to examine this option.
                                               (cont)



--
Wales Larrison
Internet: [e-mail]
Compuserve: >internet:[e-mail]
--------------------------------------------------------------------------

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

Date: 14 Nov 90 16:28:26 GMT
From: usc!zaphod.mps.ohio-state.edu!van-bc!ubc-cs!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: New Shuttle Engines

In article <[e-mail]> [e-mail] (Greg Cronau/10000) writes:
>>... The Hughes/Boeing Jarvis proposal also used
>>expendable SSMEs, after they tried very hard to come up with a viable
>>scheme for reviving the F-1 and J-2 and couldn't make it work...
>
>I can understand why reviving the Saturn program would be damn near impossible,
>but what problems were encountered with reviving just the F-1 engine program?

Basically, a subset of the problems with reviving the Saturn.  The hardware
was long out of production and quite a bit of tooling and knowledge about
production processes and operations had gotten lost.  It would have required
extensive re-engineering and re-testing to produce flight-qualified engines.

(Some people may not realize just how difficult it is to duplicate a modern
high-tech product without full manufacturing data.  The problem is not that
you can't figure out what shape the turbopump blades (for example) should be,
but that it's very hard to reverse-engineer the exact heat-treatment process
used to make them durable enough.  Especially if the subcontractor who made
them has gone out of business and all records have been lost.)

People who were involved tell me that Boeing tried *very* hard to use the
old engine designs, to avoid the SSMEs and SRBs, but just could not come
up with a plan that looked economically viable.
--
"I don't *want* to be normal!"         | Henry Spencer at U of Toronto Zoology
"Not to worry."                        |  [e-mail]   utzoo!henry

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

From: Barak Pearlmutter <[e-mail]>
Date: Wed, 14 Nov 90 19:23:02 EST
Subject: Pity The Much Abused Shuttle

People have been doing some serious space shuttle bashing on this
forum for a while now, and I don't think it's fair.

The basic argument against the shuttle runs like this:

 (1) What we need is:
     (a) the ability to lift big satellites into orbit
     (b) the ability to lift small numbers of people into orbit
     (c) the ability to get small numbers of people down from orbit

 (2) Need (a) is met much more economically by big dumb rockets than by
     the shuttle; (b) is likewise met by small dumb rockets; and (c) is
     met by simple space capsules.

 (3) Since the shuttle is so much more expensive to operate than these
     alternative means of meeting our space transportation needs, we
     should scrap it, or at least be sorry we built it.

The reason I do not find this argument convincing is that I don't buy
the premise!  Remember back when the shuttle was being designed; back
in the 70s.  Way back then, the militarization of space seemed
inevitable, and the Soviet Union was a threat to our security rather
than the meek client state it has now become.

NASA has always been a dual purpose agency, pursuing civilian goals
which frequently have clear and important military utility, and
coordinating their activities closely with the military.  For
instance, many of our ballistic missiles are based on civilian
launchers, many of the shuttle's missions are military, and most
astronauts are members of the armed forces.

Viewed in this context, the shuttle should be seen as a dual purpose
vehicle.  Rather than a space truck, it's more like a space pickup or
jeep.  In a space battle, it would be a formidable weapon.  It is
manned, giving it flexibility and the ability to operate when command
and control structures have failed, which would be likely if a war
escalated into space.  The shuttle's electronics are certainly proof
against EMP, with core memories and high redundancy.  The large cargo
space can hold a couple weapons, allowing the shuttle to act as a
roving satellite killer.  In the event that manned space stations are
important, people could be tossed in a pressurized can in the cargo
compartment, allowing a considerable boarding party to be transported
to an enemy space station if necessary.  If our spy satellites have
been taken out, and our ground stations are in disarray, the shuttle
can just fly by with a telescope and a couple 35mm cameras.  If we
think a satellite is nasty but aren't sure, or aren't sure what it's
for, the shuttle can just mosey on over and have a look.  And--here's
the coup de gras--it can just reach out it's arm and plop an enemy
satellite in the cargo bay!  This would be of incalculable
intelligence benefit.

So we want a utility vehicle use in space warfare.  Now, how can we
get it debugged and gain operational practice during peacetime?  Well,
the most reasonable thing to do is to put it to civilian use in the
meantime, thus getting some practical benefit from the beast while
gaining operational experience and maintaining readiness.

For this reason, it is unfair to charge the full operational and
depreciation costs of the shuttle to civilian cargoes, as the
experience being gained, and the practice at getting the shuttle
serviced and turned around quickly, is of considerable military
importance, is primarily of benefit to the military, and should
therefore be charged against a military budget.  Besides, the military
would have to run the shuttle anyway to keep the cobwebs off, and any
civilian benefit is pure gravy.  As I see it, this is the primary
reason that the full costs of running the shuttle are being hidden
from users: because that's the fair thing to do.

Of course, things didn't quite work out the way we thought they would.
Space has not become militarized, and is unlikely to be.  So the
scenario that motivated the construction of the shuttle hasn't come to
pass, and the shuttle is left without it's intended military role,
obsolete due to future shock.  Same goes for most of our nuclear
forces, for that matter.

Well, if the shuttle is really obsolete, we should just run them into
the ground, and not replace them as they bust, because the up front
costs are already spent, and after all we're not going to get the
construction or design costs back if we mothball them, and
depreciation is one hundred percent if we decide not to fly them at
all, so you can't count depreciation against them.  We're in a shuttle
wind-down phase now, eking out the last dregs.

It is cause to rejoice when a weapon system we had every reason to
fear we'd need turns out to be unnecessary.  On the other hand, maybe
we should have been able to figure out that space wouldn't become
militarized; the reasons, namely vulnerability and expense, seem
pretty obvious in retrospect.  That would certainly have saved some
money.  But military projects frequently outlive their motivating
scenarios; that doesn't make the projects pigs.  It's an inevitable
consequence of being just human.  And maybe the shuttle actually
prevented the militarization of space, by being such a big gun that
the USSR would have been crazy to try to fight it.  If so, maybe it
actually saved us a lot of money and anxiety.

So, to those of you criticizing the shuttle for not being a Space Mac
Truck or a Space Yugo: sorry, but it wasn't meant to be.  It's a Space
Jeep.  With a place to bolt on extra seats, or light artillery, or
haul a double handful of tents, as the need may be.  Not as cheap as a
civilian vehicle.  But after all, it's mil spec.

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

Date: 15 Nov 90 02:46:55 GMT
From: swrinde!zaphod.mps.ohio-state.edu!wuarchive!rex!rouge![e-mail]  (Fraering Philip)
Subject: Re: Pity The Much Abused Shuttle

You don't get it. The shuttles cost billions a piece, and would
cost only a couple million to destroy.

Look at the old U.S. Asat design:

You know, the one that launches from a F-15?

It would very easily punch a 20-foot hole though whatever part of the
shuttle it happened to hit. And if you don't think the Russians could
build anything comparable, well, there's lots of sand in California
you can bury your hand in. All they need is a large phased-array radar and
a rocket. They launch the rocket (which has a warhead like a claymore mine
50 feet long) to the shuttle's altitude in its path and blow it up.
What happens when the shuttle hits the cloud of ball bearings at orbital
velocity is an exercise for the reader. Simply scale up (it is linearly
dependent on mass) the effect of paint chips that weigh significantly
less...

Then the Russians have wonders of wonders destroyed 25% of the entire fleet.

Their next _expendable_ shot would destroy another billion dollar jeep...

Think before you post next time.

Phil Fraering
[e-mail]

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

Date: 15 Nov 90 03:25:38 GMT
From: lib![e-mail]  (Jay Maynard)
Subject: Re: LNLL Inflatable Stations

In article <[e-mail]> [e-mail] (M Parigi) writes:
>    I don't know about you, but if I were an astronaut doing an EVA to fix
>a section of the rotating platform (from damage by space flotsam) and had to
>get out to the 1 g region, I would first have to spin my body, climb down
>the rotating station hanging on to it for dear life, with the whole universe
>and earth rotating at 4 times per second above your head, with an uncomfortable
>suit on, I certainly wouldn't be in any mood to do any work! I think if the
>kevlar shell did get damaged, the only way to get a human on the outside of
>the spinning section would be to have it despun!
>    Have you thought about this, Allen?

...For a literary treatment of just such a subject, see Heinlein's short
story, "Ordeal in Space," in _The Past Through Tomorrow_. After reading
that, you wouldn't get _me_ out to the end of LLNL's spinning hot dog on
the outside...
--
Jay Maynard, EMT-P, K5ZC, PP-ASEL | Never ascribe to malice that which can
[e-mail]  | adequately be explained by stupidity.
         "With design like this, who needs bugs?" - Boyd Roberts

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

Date: 14 Nov 90 17:22:11 GMT
From: usc!zaphod.mps.ohio-state.edu!van-bc!ubc-cs!news-server.csri.toronto.edu!utgpu!utzoo![e-mail]  (Henry Spencer)
Subject: Re: CRAF/Cassini Update - 11/09/90

In article <[e-mail]> [e-mail] (Nikhil R. Joshi  [e-mail]) writes:
> Was the Viking lander at least partially solar powered? ...

No, the Viking landers (there were two) used RTGs.  The surface of Mars
is not a good place for solar power.  You have the usual annoying problem
of it being night half the time, but the real killer is the dust storms,
which can cut surface illumination to nearly zero for months at a time.

> ... But then why can't we
> put an RTG like Voyager's on the probe?

The problem is not power, but the total lack of information on surface
conditions.
--
"I don't *want* to be normal!"         | Henry Spencer at U of Toronto Zoology
"Not to worry."                        |  [e-mail]   utzoo!henry

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

End of SPACE Digest V12 #562
*******************