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From: pamp@bcsaic.UUCP (pam pincha)
Newsgroups: net.space
Subject: Re: Did the Challenger Wobble?
Message-ID: <462@bcsaic.UUCP>
Date: Tue, 25-Feb-86 16:45:25 EST
Article-I.D.: bcsaic.462
Posted: Tue Feb 25 16:45:25 1986
Date-Received: Sun, 2-Mar-86 18:58:36 EST
References: <8602202058.AA00624@mcchi-proteus>
Reply-To: pamp@bcsaic.UUCP (pam pincha)
Organization: Boeing Computer Services AI Center, Seattle
Lines: 25

In article <8602202058.AA00624@mcchi-proteus> cater%mcchi2@MCC.ARPA (John P. Cater) writes:
>It's my guess that what you see on your tape, when speeded up, is nothing
>more than the normal course and alignment corrections produced by the
>steerable rocket engines.  These adjustable jets make the orbiter-
>SRB system fly slightly like a bicycle rides (a constant wobbling motion) to
>maintain positional stability.  Remember, that system in not in a 
>maximally stable position when flying vertical and being pushed from the 
>rear (try balancing a pencil on your fingertip -- the only possible
>way to do it is to wobble your finger back and forth to maintain
>vertical stability).  So I think you are seeing a normal artifact of the
>guidance control. I may be wrong, but my bet's on normal guidance wobble.
> 
Actually, the information coming out in the time table info at the
commission talks seem to indicate that the Shuttle DID WOBBLE just
before the accident. In fact the guidence system was trying to correct
for the wobble just as everything blew. I suggest you try to correlate
the tracking data with the tape. I don't believe that this fellow
picked-up just a normal event.

(Note: For those interested, CNN and C-SPAN cable networks have been
airing the Comission talks. C-Span even showed a whole week's worth
of talks the last couple of weekends. I recommend watching. It's rather
instructive.)

P.M.Pincha-Wagener