Based on the press briefing:
What hit the tiles appeared to be only insulation. The tiles are brittle,
but a chunk of insulation shouldn't have damaged them.
Based purely on sensors failure sequences the failure APPEARED to progress
from the trailing edge of the left wing, forward. However, this could be
explained by alternate damage to the wiring harnesses. So APPEARED is
highly stressed. There has been more substantial tile damage in the past
that has not created this problem on reentry.
The failure did occur during the highest heating point in the landing
cycle.
Crew did not report a loss of control, nor any vehicle originated sensor
anomalies (ground reported the failures back to the shuttle, who was in the
process of acknowledging when contact was lost).
NASA stresses that while it's easy to make the insulation hit look like the
smoking gun, rarely in a system as complex as the shuttle is something so
cut and dried.
There is no mechanism for inspecting the bottom side of the shuttle, nor
ANY method for inflight repairs.
When they lost the drogue chute door a few missions ago, they said that
"remote observation" yielded no clues. Very vague, but I presume they had
the SRO turn a bird on the shuttles rear. However, the lighting was
unlikely to be ideal, and camera angle may have played a part. As a result
of the lack of success with remote observation last time, they elected not
to do it this time, either. And the tiles are black, so it would be hard to
discern any detail.
Exhaustive analysis was done based on the crew films of the external tank
and the ground cameras. They're pretty convinced there is no hardware in
the chunk of insulation that hit.
That's about it, for now.
In the press briefing, too many idiotic reporters were asking the same
questions. And the one woman that asked the smart question that I had been
wondering about was glossed over. That being were any SRO assets focused on
the shuttle during re-entry. I realize that the pan speed of the cameras
may be slow, but the widefield views still have a lot of detail.
The other question that was never asked is what intrinsically explosive
gases or fluids run through the wing area. Hydrazine? Hydrogen? Any O2
tanks in the wing? Could one of them have ruptured or sparked off and blown
away part of the wing?
--John
> -----Original Message-----
> From: cctalk-admin_at_classiccmp.org
> [mailto:cctalk-admin_at_classiccmp.org]On
> Behalf Of Adrian Vickers
> Sent: Saturday, February 01, 2003 17:34
> To: cctalk_at_classiccmp.org
> Subject: Re: Columbia
>
>
> At 20:38 01/02/2003, you wrote:
>
> >Somewhat speculative info:
> >
> >I heard on ABC news this afternoon that there had been
> >some external fuel tank insulation knocked off during
> >launch of the Columbia, and it had impacted the wing
> >surface or some such on I think the left side. Then
> >there's a report of a temperature variation in the
> >same wing during the early reentry period.
>
> Although that sounds somewhat implausible (how would ABC
> know, when no-one
> else does?), I wouldn't be entirely surprised if it was the case.
>
> Incidentally, does anyone know if Columbia had been updated
> to the latest
> flight s/w & h/w? I know there was work on-going to do this,
> but I've no
> knowledge of what stage they'd got to.
>
> >The news report said that since the mission didn't
> >have the mech arm they couldn't inspect the wing
> >during the mission, but used instead video footage of
> >the launch to determine that there wasn't any damage.
> >
> >Perhaps, unfortunately, it was worse after the
> >vibrations of launch?
>
> It seems to me that maybe a little complacency might have set
> in. Maybe
> they've landed slightly damaged orbiters before, with no ill effects.
> Certainly the post-Challenger analysis was that safety
> procedures were less
> rigorous than they ought to have been. There've been nearly a hundred
> flights since then (or is it slightly more, I forget), maybe
> - just maybe -
> someone made a wrong call based on the fact "it's always
> worked before".
>
> The trouble is, even if they'd aborted the landing (before
> the Shuttle left
> ISS presumably), what then?
>
> I do feel for the astronaut's families, and in almost equal
> measure for the
> future of humanity in space. We have *got* to find a better
> way of getting
> in and out of the gravity well.
>
> --
> Cheers, Ade.
> Be where it's at, B-Racing!
> http://b-racing.com
Received on Sat Feb 01 2003 - 17:22:00 GMT