Newsgroups: sci.space.shuttle
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: Orbiter/SRB separation
Message-ID: <1988Jun5.025213.23613@utzoo.uucp>
Organization: U of Toronto Zoology
References: <50665@ti-csl.CSNET>
Date: Sun, 5 Jun 88 02:52:13 GMT

> ... As long as the various
> components separate cleanly, and don't make any extremely radical changes in 
> relation to flight path, I see no reason why the OV and ET/SRB (as separate
> units) couldn't stay intact...

As I've mentioned before, the aerodynamics of this sort of separation
process are not trivial and should not be assumed to be trouble-free.
Military aircraft are tested very carefully for proper separation of
missiles, drop tanks, etc.

> Besides, if the SSME's were still burning, at
> least at partial throttle as I suggested above, the "jerk" would be greatly
> reduced (if it matters at all), and the OV could quickly accelerate away 
> from the impending ET/SRB fireball (or whatever)...

Uh, using what for fuel?  The orbiter has no built-in tanks for the SSMEs,
only for the low-thrust OMS.  The SSMEs would have to be shut down either
before or at the instant of separation.  Once it separates, the orbiter is
a glider; the ET/SRB combination will quickly accelerate away from it,
potentially exposing it to the SRB exhaust.  (Those who still think this
is a trivial issue should consider that rocket engines have been used
experimentally for drilling tunnels through hard rock; close-range exposure
to the exhaust of a big rocket engine is likely to be fatal to something
as flimsy as a shuttle orbiter).
-- 
"For perfect safety... sit on a fence|  Henry Spencer @ U of Toronto Zoology
and watch the birds." --Wilbur Wright| {ihnp4,decvax,uunet!mnetor}!utzoo!henry