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From: eugene@ames.UUCP (Eugene Miya)
Newsgroups: net.space
Subject: Re: Computer Shuttle Landing
Message-ID: <706@ames.UUCP>
Date: Sat, 15-Dec-84 17:22:02 EST
Article-I.D.: ames.706
Posted: Sat Dec 15 17:22:02 1984
Date-Received: Wed, 19-Dec-84 03:25:12 EST
References: <-2700@tektools.UUCP> <73300001@hpfclq.UUCP> <18025@lanl.ARPA>
Organization: NASA-Ames Research Center, Mtn. View, CA
Lines: 51

> > 
> > 
> > I believe the answer is "yes".  I know that the on-board flight
> > computers land the vehicle but I don't remember if they also inject
> > the Shuttle into the re-entry path.  I also think that it wasn't
> > until the sixth misssion that a pilot actually landed the craft
> > manually.  Knowing NASA, it seems to me that they probably could land
> > the Shuttle without human help for safety reasons if nothing else.

No, not quite.  The Shuttle is not THAT automated.  You give it too much
credit.

> 
> 
> I remember it the other way around!  I don't think the computer was
> allowed to control the whole landing sequence until the fifth or sixth
> flight.  The reentry burn has traditionally been computer (or even
> ground) controlled* but the actual landing of the shuttle is similar
> enough to conventional aircraft that the final part of the landing
> sequence is usually handled by the pilot.  Except for the Shuttle and
> some carrier based aircraft I don't think that there are ANY aircraft
> that are presently even capable of fully automated landing.  As I
> remember, the Shuttle was landed manually for the first few flights in
> order to more fully test the flight computer.  Each of the first few
> flights remained under computer control until successively later times
> in the reentry sequence, until the computer finally landed the craft
> on its own.  Is there anyone out ther who actually KNOWS?
> 
> * - Remember the problems caused when the automatic controls failed on
>     the Mercury flights and the pilot had to control the attitude for
>     the reentry burn manually.

jlg is right.  Some Shuttle pilots went thru here the other day, and I
will be going down to Dryden next month [to look at our ELXSI] and I
can inquire about reentry burn.  To be fully truthful about the
computers, it's a matter of degree [just like there are dozens of different
types of flight simulators (some move, other don't, some don't have
the pretty pictures, etc.)].  The Shuttle is not a "fly by wire" craft like
a 747.  Everything is digitally relayed so computers "fly" to differing
degrees.

A fair portion of this is due to pilot desire [everybody else at Ames
is going to jump on me for this!].  We had a Director's Colloquia on
the subject automating aircraft.  Many PILOTs don't want this.
[You read or see Tom Wolfe?]  One plane to watch by the way is the
X-29 which is heavily wired.  

--eugene miya
  NASA Ames Research Center
  {hplabs,ihnp4,dual,hao,vortex}!ames!aurora!eugene
  emiya@ames-vmsb.ARPA