Newsgroups: sci.space.shuttle
Path: utzoo!henry
From: henry@utzoo.uucp (Henry Spencer)
Subject: Re: shuttle escape systems
Message-ID: <1989Oct26.165608.5154@utzoo.uucp>
Organization: U of Toronto Zoology
References: <1989Oct12.021826.7915@utzoo.uucp> <23280001@hpcvia.CV.HP.COM>
Date: Thu, 26 Oct 89 16:56:08 GMT

In article <23280001@hpcvia.CV.HP.COM> kas@hpcvia.CV.HP.COM (ken_scofield) writes:
>>(For those who aren't up on this, a Return To Launch Site abort involves
>>doing a U-turn at hypersonic speeds.)
>
>  OK, here's a question I've been wanting to ask for a long time:  Why is the
>  (apparently) preferred manuever a "pitch over"?  
>
>  I assume that the manuever is a half-inside-loop, such that the initially
>  upside-down shuttle comes out of the bottom of the loop right-side-up and
>  heading back toward KSC.  This seems fairly simple in principle, but isn't
>  there going to be a loss of gobs and gobs of (I assume) precious altitude?

I *think* the answer is "you're thinking aircraft, when you should be
thinking rocket".  This maneuver is being done at extremely high altitude
by a vehicle with powerful rocket engines still operating.  Any loss of
altitude can be fixed in seconds by pitching up a bit afterwards.

>  And one last question:  Is the ET still attached during RTLS abort...

Yes.  RTLS involves *thrusting* backward, not just doing a gliding U-turn.
(Again, rocket, not aircraft.)  The ET is attached and the main engines
are still firing.
-- 
A bit of tolerance is worth a  |     Henry Spencer at U of Toronto Zoology
megabyte of flaming.           | uunet!attcan!utzoo!henry henry@zoo.toronto.edu