Date: Wed, 30 Dec 92 05:21:49    
From: Space Digest maintainer <digests@isu.isunet.edu>
Reply-To: Space-request@isu.isunet.edu
Subject: Space Digest V15 #612
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Space Digest                Wed, 30 Dec 92       Volume 15 : Issue 612

Today's Topics:
                       Aluminum as rocket fuel?
        Stupid Shut Cost arguements (was Re: Terminal Velocity

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Date: Wed, 30 Dec 1992 06:56:04 GMT
From: Nick Janow <Nick_Janow@mindlink.bc.ca>
Subject: Aluminum as rocket fuel?
Newsgroups: sci.space

roberts@cmr.ncsl.nist.gov (John Roberts) writes:

> For final injection, it occurs to me that using gaseous oxygen to "blow"
> the powdered aluminum in might be an option.

That might work.  The aluminum could be formed as microfine droplets, and
then coated with another material to protect it from the oxygen until it
reaches the high-temperature reaction area.

What are the problems with using molten aluminum sprayed into the reaction
area?  Keeping the aluminum molten in a vacuum should be relatively easy.

--

Nick_Janow@mindlink.bc.ca

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

Date: 29 Dec 92 22:27:37
From: John McCarthy <jmc@SAIL.Stanford.EDU>
Subject: Stupid Shut Cost arguements (was Re: Terminal Velocity
Newsgroups: sci.space

The reason Shuttle costs are so much more than projected is that the
Shuttle requires this army to maintain it between flights.  Hydrogen
isn't much more expensive than expected, and I doubt the solid fuel
is either.  When the Shuttle was first proposed, the idea of operating
it like an airline was part of the plan from the beginning.  It
turned out that the Shuttle operated too close to the limits of the
materials and structures of which it was made.  That's why it needs
so much maintenance.

If someone proposes a new reusable vehicle for going to earth orbit,
it is reasonable to ask why its maintenance costs can be expected to
be a lot less than those of the Shuttle.  Any answer you get needs to
be evaluated skeptically.
--
John McCarthy, Computer Science Department, Stanford, CA 94305
*
He who refuses to do arithmetic is doomed to talk nonsense.

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

From: Shari L Brooks <bafta@cats.ucsc.edu>
Newsgroups: sci.space

Subject: Re: fast-track failures
Message-Id: <1hrcplINNd4u@darkstar.UCSC.EDU>
Date: 30 Dec 92 05:41:09 GMT
References: <1992Dec20.192544.2996@ke4zv.uucp> <ewright.725152007@convex.convex.com> <1992Dec29.164256.18889@murdoch.acc.Virginia.EDU>
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In article <1992Dec29.164256.18889@murdoch.acc.Virginia.EDU> 
rbw3q@rayleigh.mech.Virginia.EDU (Brad Whitehurst) writes:

>In article <ewright.725152007@convex.convex.com> ewright@convex.com (Edward 
>V. Wright) writes:

>>You think a typical engineer earns $100,000 a year?
>>
>>I want to work for your company!

>	By the time you also pay for FICA, pension, benefits, and
>overhead, a $50,000 engineer can easily cost a company double his base
>pay!  BTW, Ed, I ALSO help do the budgeting for my lab, so before you
>ask, yes, I have some experience in this!

Wow, your lab pays for FICA?  I'm impressed.  It takes up about a third
of *my* salary, when combined with income taxes.  Right out of my pay.
I was under the impression it came out of everyone's pay, that that was
the idea behind "Social Security".

-- 
If you blow fire against the wind, take care to not get the smoke in your eyes.
      Big & Growly Dragon-monster        |       bafta@cats.ucsc.edu
   --------> shari brooks <--------      |    brooks@windee.arc.nasa.gov
                      The above opinions are solely my own.

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

End of Space Digest Volume 15 : Issue 612
------------------------------