IIRC, the Apollo capsule wire insulation was FEP, and was ignited when the
power conductor it insulated was mechanically pinched and shorted to ground.
It overheated enough from fault current to ignite before the breaker
tripped.

Kapton tape was blamed in the Swissair 400(?) cockpit fire and crash in
Newfoundland(?) a few years back.

Gasoline vapor fuel fires were ignited by early pagers and first generation
cell phones which used tiny universal motors with eccentric weights as
silent ring annunciators. Find one of those old beasts and try running that
motor in a flammable environment.

The technical basis of this is covered in a text: "Intrinsic Safety" by
Redding, published by Mc Graw Hill.

--

Crazy George
Remove N O and S P A M imbedded in return address
"DarkMatter" wrote in message
...
On Wed, 17 Mar 2004 21:33:43 GMT, Dave Shrader
Gave us:


So, it is possible that pressing the PTT or the ON/OFF switch causes the
necessary spark.

Both in handheld radio transceivers, and cell phones, there are NO
switches that pass any power level that causes a spark to exhibit upon
contact or release.

Sheesh.

Remember the Apollo ground fire.

It was a pure oxy environment. There was, as a rule nothing
flammable on board. The problem was that materials were not tested
for their flammability in such an oxy rich environ. The kapton tape
is what was set afire by the spark, and that fire grew ferociously in
the oxygen. The oxygen was the oxidizer, not what burned.

A switch/spark caused
an oxygen explosion.

Are you sure you aren't just pulling that one out of you ass as
well? I was taught that it was the spark caused by a dropped wrench,
and that tape is what burned. An explosion would have blown the craft
open from the inside. That did not happen.

One would think that all the switches on Apollo were already gas
tight.