Newsgroups: sci.space.shuttle
From: henry@spsystems.net (Henry Spencer)
Subject: Re: Debris hits
Date: Wed, 11 Nov 1998 16:56:55 GMT

In article <sparks-0911981942300001@lrport7.csd.sc.edu>,
Sparks and Dr. Jules <sparks@campfour.win.net> wrote:
>"Inspections of Discovery's underside revealed about 136 debris hits to
>the black thermal protective tiles with about 42 hits measuring 1 inch or
>greater."
>
>just wondering if these were small meteorite hits while in orbit or while
>in reentry...

Most of those will have been hits during launch and landing, actually.
There is often quite a bit of flying debris during launch, in particular.

>I wonder how large an object the orbitor can handle being hit with and and
>what kind of protection the orbitor has to protect itself from these
>"hits"

An object a millimeter across probably wouldn't do anything drastic.  An
object a centimeter across could be big trouble.  I don't know just how
the situation looks in between.

About the only thing the orbiter can do for protection is to try to point
its vulnerable areas -- the windows in particular, and the upper surface
in general -- away from trouble.  When the orbiter deploys a satellite
with an upper stage, for example, it's routine to point the orbiter's
belly at the satellite at upper-stage ignition time.
--
Mass-market software technology has |  Henry Spencer   henry@spsystems.net
been deteriorating, not improving.  |      (aka henry@zoo.toronto.edu)