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Date: Tue, 12 Mar 91 02:21:17 -0500 (EST)
Subject: SPACE Digest V13 #263

SPACE Digest                                     Volume 13 : Issue 263

Today's Topics:
Re: German conference highlights doubts about ESA's manned space plans
		      Magellan Update - 03/11/91
		Re: Value per pound vs. cost per pound
   Round 2: CFD, reorganization of the misc.jobs.offered heirarchy
			Re: O-Ring and Feynman
			  Re: Space Profits

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

Date: 11 Mar 91 16:56:26 GMT
From: swrinde!cs.utexas.edu!uwm.edu!ux1.cso.uiuc.edu!usenet@ucsd.edu  (Doug McDonald)
Subject: Re: German conference highlights doubts about ESA's manned space plans


In article <1991Mar11.165626.25181@zoo.toronto.edu> kcarroll@zoo.toronto.edu (Kieran A. Carroll) writes:
>
>All those satellites that we've seen fail on orbit, including the ones that
>the Shuttle was sent up to repair, were designed by people who tried
>to ``make sure that it works'' befoire launch. Many of the people involved 
>in design of these are very smart, and very conscientious, probably more so
>than you and I.

No comment.

> Satellites don't typically fail because of sloppy design or 
>construction. They fail because >nobody< can imagine beforehand >all< the things 
>that might go wrong with a complicated, custom-built device.
>


True but irrelevant!!!! Most fatal problems are so simple that they
CAN be expected!


I certainly can imagine that a Viton O-Ring exposed to very high sudden
load changes would fail if cooled to 20 degrees F before use!!! It 
is blatently obvious to anybody who either hs USED them - or to anybody
who reads the blurb sheets on O-Rings published by the Parker Co.


I certainly can imagine that if you fail to test the components of 
a Cassegrain telescope together that you risk having problems.


Examples of something that might be beyond guessing beforehand is the
sunlight induced jitter problem in the Hubble.


Doug McDonald

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

Date: 12 Mar 91 00:47:11 GMT
From: swrinde!elroy.jpl.nasa.gov!jato!mars.jpl.nasa.gov!baalke@ucsd.edu  (Ron Baalke)
Subject: Magellan Update - 03/11/91


                          MAGELLAN STATUS REPORT
                              March 11, 1991
 
     The Magellan spacecraft is performing nominally.  All but one of the
STARCALS (star calibrations) during the weekend were successful.  The DESATS
(desaturations of the reactions wheels) were successful.
 
     The spacecraft temperatures continue to be in the acceptable range.  Bay
10 of the spacecraft bus has gone up slightly and is currently at 68 degrees C,
with an alarm limit of 75 degrees C.
 
     The Spacecraft Team is performing a sequence load of AACS (Attitude and
Articulation Control Subsystem) Memory B, which had been disabled since soon
after the second spacecraft anomaly last August.  A memory readout test is
scheduled for tomorrow.  When the testing is complete later this week, the new
sequence load will make Memory B fully functional and restore the memory
redundancy.
 
     The weekly command upload M1072 with its associated parameter files is
scheduled for tomorrow evening.
      ___    _____     ___
     /_ /|  /____/ \  /_ /|      Ron Baalke         | baalke@mars.jpl.nasa.gov
     | | | |  __ \ /| | | |      Jet Propulsion Lab | 
  ___| | | | |__) |/  | | |___   M/S 301-355        | Change is constant. 
 /___| | | |  ___/    | |/__ /|  Pasadena, CA 91109 | 
 |_____|/  |_|/       |_____|/                      |

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

Date: 11 Mar 91 21:28:39 GMT
From: usc!rpi!zaphod.mps.ohio-state.edu!samsung!rex!rouge!dlbres10@ucsd.edu  (Fraering Philip)
Subject: Re: Value per pound vs. cost per pound

In article <21317@crg5.UUCP> szabo@crg5.UUCP (Nick Szabo) writes:

>Essentially, space transportation customers want what every other 
>transportation customer wants (surprise!).  Chemical rockets seem 
>to be only capable of meeting these needs at a rate over
>$5,000/lb.


>-- 
>Nick Szabo			szabo@sequent.com
>"What are the _facts_, and to how many decimal places?"  -- RAH

Two comments:

1. Okay, I want to see the facts on that assertion about the limiting
factor in chemical rocket price, and to several different decimal
places. To paraphrase RAH, it's math, or it's opinion. I tell you
what, I have a friend who knows Max Hunter. I might even be able to
get you his phone number. Then you can ask him why he thinks he can do
it for a lot less than five thousand a pound. Also, let's start using
different units: kg instead of pounds, and Canadian instead of
American dollars.

2. Re: Pegasus: Its first customer was military. And for commercial
work, OSC has proposed its Taurus vehicle more than Pegasus. For those
of you who don't know about Taurus, it seems to basically be a Pegasus
without wings on top of an MX first stage. It also seems that Pegasus
is meant to be military than commercial in that commercial payloads
don't need to be launchable from anywhere. At the expense (additional,
it may seem, for with Taurus OSC seems to be abandoning the approach)
of having to pay for a carrier aircraft, Pegasus can launch anywhere
the plane can take off. Adding onto the quality of rapid dispersement,
etc... 

Heck, our military probrably needs a Pegasus-like vehicle. But if
Pegasus is so good, why are they developing Taurus? I feel certian
that I'm not the only one who wants to know.

Phil Fraering
dlbres10@pc.usl.edu

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

Date: 11 Mar 91 21:57:18 GMT
From: sdd.hp.com!usc!skat.usc.edu!kriz@ucsd.edu  (Dennis Kriz)
Subject: Round 2: CFD, reorganization of the misc.jobs.offered heirarchy


From last week's discussion the following proposal seemed to get the most
support.  It would break the existing "misc.jobs.offered" news-group into:

	misc.jobs.offered.sci.comp -- job offerings in CS
	misc.jobs.offered.sci.engr -- job offerings in engineering
	misc.jobs.offered.sci      -- job offerings in the sciences 
	misc.jobs.offered          -- all other job offerings

Any further comments/suggestions?

dennis
kriz@skat.usc.edu

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

Date: 11 Mar 91 23:50:22 GMT
From: marf@athena.mit.edu  (Matthew R Feulner)
Subject: Re: O-Ring and Feynman

In article <1991Mar11.150257.28368@nstn.ns.ca> roberts@Iris1.ucis.dal.ca (Greg Roberts) writes:
>I have the most absoluterespect for Feynman. He took at the technical mumbo
>jumbo from the MT engineering staff, and made it crystal clear so that anyone,
>including Neil Armstrong, could understand it. Temperature. O-Ring. Failure.
>
>Greg
>Department of Mechanical Engineering, TUNS

I hardly think Neil Armstrong should be singled out since he has either
a bachelors or masters degree in aerospace engineering from Purdue.  Do
you think he's an idiot?  How demeaning.

Matthew Feulner

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

Date: 12 Mar 91 03:27:26 GMT
From: sun-barr!ccut!wnoc-tyo-news!astemgw!kuis!rins!will@ames.arc.nasa.gov  (will)
Subject: Re: Space Profits

In article <21314@crg5.UUCP>, szabo@crg5.UUCP (Nick Szabo) writes:

> Current space infrastructure is being designed from scratch by
> government agencies, with no economically scaled antecedents, and
> with business analysis (if any) thrown in as an afterthought.  In large
> part, that why it is failing.

	I agree that in the past this was true, but, and I mean BUT, in todays
society (In America), most of these people that are doing this stuff by scratch
don't even understand the difference between the space shuttle and their cars.

	You can congradulate the U.S. government on this, It distroyed the U.S.
educational system.

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

End of SPACE Digest V13 #263
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