Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!accuvax.nwu.edu!delta.eecs.nwu.edu!phil
From: phil@delta.eecs.nwu.edu (William LeFebvre)
Newsgroups: sci.space.shuttle
Subject: Re: shuttle escape systems
Message-ID: <1321@accuvax.nwu.edu>
Date: 17 Oct 89 22:06:34 GMT
References: <538.252A3A3B@mamab.FIDONET.ORG> <34577@srcsip.UUCP> <126311@sun.Eng.Sun.COM> <1307@accuvax.nwu.edu> <15596@netnews.upenn.edu>
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Reply-To: phil@delta.eecs.nwu.edu (William LeFebvre)
Organization: Northwestern U, Evanston IL, USA
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In article <15596@netnews.upenn.edu> santerel@clarke.cis.upenn.edu.UUCP (Walter Santarelli) writes:
>In article <1307@accuvax.nwu.edu> phil@delta.eecs.nwu.edu (William LeFebvre) writes:
>>separation.  It is acknowledged that the first two minutes of
>>ascent---the time when the SRBs are burning---is the most critical and
>>the most sensitive to disaster....
>
>This is the reason I'm still amazed that we launch people on the
>current system at all. I believe the original concept called for a
>re-usable liquid fueled booster. Liquid fueled boosters offer the
>advantage that they can be throttled....

And the disadvantage that they are much more volatile.  The actual
explosion that broke up the Challenger was the nearly instantaneous
combustion of the liquid fuel, NOT the solid fuel (and if you want to
be picky, the solid fuel wasn't even the initial technical cause---the
segmented booster construction was).  It's a matter of tradeoffs.

I am of the impression that solid fuel gives greater force for the
weight than liquid fuel does.  Is that not true?

>It's the system we've got now, might as well use it as safely as
>possible. Hopefully the next vehicle won't suffer from the budget
>cutter's axe in quite the same way.

And hopefully it will be much safer.  Let's hope future space
shuttle/plane builders learn from the mistakes of the STS program!

		William LeFebvre
		Department of Electrical Engineering and Computer Science
		Northwestern University
		<phil@eecs.nwu.edu>