In a message dated 3/25/99 2:22:54 PM Pacific Standard Time,
[log in to unmask] writes:

<< Hi Phil
 I think the Kapton issue in aircraft relates to an incident with Boeing 747.
 I believe over time the Kapton can deteriorate and wires short out causing
 sparks, which from memory of the TV article I saw, was a possible
 cause of the centre fuel tank explosion.
 You may like to try Boeing for clarification. Or maybe FAA incident
 reports.
 Regards - Garry >>

Hi Phil and Garry!

    Good memory Garry! Here's a paragraph from the Systems Group Chairmans
Factual Report of the investigation of TWA Flight 800 (you can read the entire
113-pages from:         http://www.newsday.com/jet/year/exhibits.htm                    it's a *.PDF
file.

"The wiring from the scavenge pump relay was found to have deeply hot stamped
wire markings and a crack was propagating from a numeral "1". It was found
that the crack penetrated the inner layer of insulation to the core conductor.
The wire was found to be BMS13-42 (Aliphatic Polyimide) and used with a
commercial name of "Poly-X" (Made by Raychem) and has two layers. BMS13-42 is
known to have a cracking phenomenon when subjected to stress, such as tight
bend radii, according to Boeing representatives. The group noted that wiring
removed for an airworthiness directive (AD) pertaining to wing fuel pumps had
cracked insulation."

    As some of you know, they've never conclusively determined what caused the
plane to go down. They know that a fuel tank blew up, but not precisely what
caused the tank to blow. There were rumors of a missile and what-not, but it
does seem to me that a wiring problem could have caused a spark. Not to be
morbid about this, but as you look what's documented about this crash, and
where they had to recover the wreckage from, it amazes me that they can
determine the details they do about this stuff...

-Steve Gregory-

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