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From: smb@ulysses.homer.nj.att.com (Steven M. Bellovin)
Newsgroups: sci.space,sci.space.shuttle
Subject: Re: space news from May 15 AW&ST (replacing computers)
Message-ID: <11749@ulysses.homer.nj.att.com>
Date: 3 Jul 89 22:57:12 GMT
References: <1989Jul2.054432.5054@utzoo.uucp> <3827@phri.UUCP> <1989Jul2.210944.15387@utzoo.uucp>
Organization: AT&T Bell Laboratories, Murray Hill
Lines: 13

In article <1989Jul2.210944.15387@utzoo.uucp>, henry@utzoo.uucp (Henry Spencer) writes:
> The real botch here is that the computers are so inaccessible that it takes
> four hours to replace one.

Sorry, I don't necessarily agree.  As Henry obviously knows, design of
something like a space shuttle is a series of tradeoffs.  While accessbility
of the computers for replacement is certainly important, so is accessiblity
of other equipment, lockers, etc.  The designers felt -- rightly, I'd say --
that in-orbit failure was a comparatively low probability, and chose not
to optimize for such a situation.  Given that this is the first time
the replacement has been done, I'd have to agree with them.

		--Steve Bellovin