On Monday 03 February 2003 11:28 pm, Bill Brandt wrote:
> Christian - I heard someone suggest something today on the radio that made
> the most sense. It wasn't the tiles - because they have lost tiles before
> without catastrophic consequences. The leading edge of the wing has the
> most heat during re-entry (obviously) and had a different material from the
> tiles.

Now that it is the most "scientific" or "accurate" source of information,
check out the "slashdot" site [slashdot.org -- you'll have to go back to the
"saturday" edition]  Note that there are two stories -- the first generated
over 2000 messages, the second some 800+  [something like a new message every
37 seconds...]

As to missing tiles, I have heard in the past they can lose some tiles "as a
percentage of the whole" and not have a problem -- I think the assumption is
the tiles are lost in various/random locations and not lost in a localized
area.  That said, the last transmission had to do with tire pressure, with a
request for a repeat of the message.  Although the request to repeat was due
to the fact the original transmission was garbled, it does bring up some
assumptions: (1) the pressure reported was "abnormal" -- if the pressure
reported "sounded" normal (though garbled), there may not have been a need to
request confirmation -- we humans are remarkably adept at deciphering words
in noisy environments ESPECIALLY when the word spoken is the one we are
expecting  [note: I haven't heard a recording of the actual transmission, so
it may have been so truly "garbled" that the request to repeat was truly
routine]

(2) presuming the reported pressure was unexpected, and by that I also imply
"unexpectedly HIGH", we look to a probable cause: intense heat in the wheel
well, due [most likely] to missing tiles in the affected area -- tires are
basically baloons, and if they get hot, they expand like a hot-air baloon,
and may eventually pop -- the resulting "explosion" could destabalize the
craft to the point where the wings get over-stressed and tear off; and the
whole thing just "cascades" in failures...

> When the foam - or whatever it was - broke off during liftoff and hit the
> wing - that's when the damage occurred. And if that was the case (who knows
> right now?) then there wouldn't have been a thing anybody could have done.
> Columbia was doomed from the liftoff.

Actually, what they could have done "on the way out" was abort the mission
before they got to space, and simply fly back to earth [ditching at sea as
"worst case"]  Apearently this "foam" has come off before, struck & removed
tiles before, so "this happened before and nothing bad came of it", so nobody
thought about it much.  I'm sure the techs that said "no problem" feel like
they are the lowest form of life on the planet right now [even below
lawyers], but I'm willing to bet the next launch that has tiles
loosened/removed due to "bits of foam" will have flight controllers jumping
all over themselve to get to the abort button...

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