NetNews Usenet Archive 1992 #18/NN_1992_18.iso/spool/sci/space/shuttle/2085

Internet Message Format | 1992-08-12 | 3.0 KB

Path: sparky!uunet!sun-barr!ames!nsisrv!herman!herman.gem.valpo.edu!mjensen
From: [e-mail] (Michael Jensen)
Newsgroups: sci.space.shuttle
Subject: Re: Crew separation for safety
Message-ID: <[e-mail]>
Date: 12 Aug 92 18:11:50 GMT
References: <[e-mail]> <[e-mail]>
Sender: [e-mail]
Distribution: world
Lines: 49
Nntp-Posting-Host: herman.gem.valpo.edu


|> >  The Europeans have been working on a launch system which greatly
|> >distances the crew and the engines- the crew sits out in a capsule in the
|> >front, which can be detached and landed separately in the event of trouble.
|> >
|> >Why does the space shuttle have the crew sitting right on the tank?  It
|> >seems to be the dumbest thing imaginable.
|>
|> This is going to sound harsher than it's meant:
|>
|> "Compared to what?"  or better yet, where *are* you going to put the crew?
|> If we look at any liquid fueld stack, there doesn't seem to be anywhere
|> that isn't effectively "sitting right on the tank."  In Apollo, there was
|> the heat shield between the crew and the CSM fuel.  I seriously doubt that
|> the CSM and even more of a laugh, the LEM, would do much to stop things
|> from going wrong if the Saturn stack blew.  Gemini had the experiments and
|> the retro fuel between it and the Atlas, Mercury much the sameonly less of
|> it.
|>
|> The idea of a seperate and separatable crew compartment has had merit in
|> the past.  Of the three stacks mentioned above, only Apollo had any way to
|> get the crew free - the escape rocket tower.  If you don't mind the mass,
|> in a game wehere payload is damn expensive and every ounce counts, crew
|> escape is possible.  STS-1 had ejection seats.   When you have a Saturn
|> class booster, 7.5M # thrust first stage,  100 tons to LEO (or was it 100
|> tons to Lunar Injection, 300+ tons to LEO, I forget) , there's room in
|> the energy/mass budget for escape systems.
|>
|> But there's no place besides the blockhouse on the ground that isn't
|> effectively "sitting on top the tank."
|>
|> Neil Kirby

Just as an additional point of info... there IS work going on designing a new
launch system to suplement the shuttle for getting crews up to Space Station
Freedom.  It is based on the HL-20 "lifting body" designed by the "skunk works".
It would use a "Titan" style launch system, and be basically a "mini-shuttle" which
would ride into orbit on the Titan.  This would allow for return to using a "escape
rocket" similar to that used during Apollo.  The reason that we can't have such a
device on the shuttle (much like Neil said) is because of the mass of the shuttle
you would end up wasting huge amounts of money to get anything similar.  Due to the
design of the shuttle, such a system (ie the Apollo one) is not feasable.


--
Michael C. Jensen                [e-mail]
Electrical Engineering                [e-mail]
Valparaiso University                [e-mail]
"I bet the human brain is a kludge." -- Marvin Minsky