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From: knudsen@IHWPT.UUCP
Newsgroups: net.space
Subject: Re: rocket engine not equivalent to balancing pencil on finger
Message-ID: <8602281649.AA00772@decwrl.DEC.COM>
Date: Fri, 28-Feb-86 08:48:09 EST
Article-I.D.: decwrl.8602281649.AA00772
Posted: Fri Feb 28 08:48:09 1986
Date-Received: Sat, 1-Mar-86 18:18:11 EST
References: <8602231417.AA19482@s1-b.arpa>
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Your analysis is good.  However, while a rocket is first lifting
off, and for a while afterwards, the relevant moment arm IS still
that of gravity, not just the engine's thrust.

So, the more a rocket leans over, the harder gravity will
pull it over some more ..

Oops -- you really are right on all counts! Cancel the above.
But you still need to point the thrust vector thru the
center of gravity (or oscillation, or percussion),
which explains why space shuttles take off a bit sideways,
with the orbiter a little bit under the tank.
	mike k