"G.R. Patterson III" wrote in message
...


Aviation wrote:

On the one hand, passengers need to get denser air to breathe
but large aircraft have oxygen masks that drop down.

If the aircraft is much above 25,000', the masks will do little good. You
need
a pressure mask to survive long at (for example) 35,000'. Those used by
the
airlines for passengers are not good enough for that.

(I could
do some rough estimates that the average fat slob can hold
their breath for less than a minute so, without masks, the jet
would have to go from let's say 30000 feet to 5000 feet in
30-45 seconds. My ears would explode.)

Nobody can hold their breath in that situation - the pressure difference
will
cause you to exhale. Above about 25,000', the air pressure is low enough
that
oxygen actually passes backwards out of your bloodstream into the lungs
and out
of the body. As for your ears, they're already toast. The pressure just
dropped
from the pressure at 8,000' to that at cruise altitude in a few seconds.

Agreed

Basically, the pilots need to get their masks on and get the plane down
below
25,000' as rapidly as it can possibly be done. The descent to 10,000' can
be made
a little more leisurely, but not much - there's always someone in the
cattle
section who panicked and isn't wearing a mask. If that's one of the flight
attendants, you're really in trouble.

Agreed.

There is 1 further issue not yet addressed. Ambient Temp at altitude.
Ambient temps of -30 degrees F or lower are not uncommon at altitudes
25,000 ASL.

Decompression, explosive or otherwise, results in a significant drop in
cabin Temp resulting in ~ fairly rapid freezing.

There have been any number of documented incidents, military & civilian,
over the years where an A/C lost pressure at altitude, disabling the crew,
with the A/C continuing on "Auto Pilot", crashing when fuel exhausted. It is
routine for A/C in this situation to be intercepted/followed/kept under
surveillance/filmed by military A/C. The most recent "Widely/Highly
Publicized Example"of this was the "Payne Stewart" incident.
Ralph Nesbitt
Professional FD/CFR/ARFF Type