Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!uunet!pilchuck!seahcx!phred!petej
From: petej@phred.UUCP (Pete Jarvis)
Newsgroups: sci.space.shuttle
Subject: Re: Will we lose another orbiter
Message-ID: <3034@phred.UUCP>
Date: 9 Apr 90 18:03:33 GMT
References: <1990Mar29.184206.16592@utzoo.uucp> <278@flight.UUCP> <1990Apr6.024844.16083@utzoo.uucp> <2836@rodan.acs.syr.edu>
Reply-To: petej@phred.UUCP (Pete Jarvis)
Organization: <2836@rodan.acs.syr.edu>o
Lines: 16

In article <2836@rodan.acs.syr.edu> amichiel@rodan.acs.syr.edu (Allen J Michielsen) writes:
>
>   On a side note, correct me if my memory has fogged considerably...
>Isn't the gear down system a spring loaded explosive system ?
>I kinda remember understanding that the gear was locked in place by
>explosive bolts, which are blown & the gear drops.  Gravity & springs
>then drop the gear.  If that's correct the gear could only stay up if
>the explosive bolts don't fire.

The explosive charges that are available to "blow" the gear down are
only activated if the gear is not down and locked within 2 seconds.
The Pilot has a 2-switch sequence to get the gear down. The first
switch arms the pyro-techics, the 2nd switch lowers the gear. The gear
then has 2 second to go down and lock. If not, they are "blown" down 
automatically.
Peter Jarvis........