Re: 42,000 feet

Date:         18 Mar 97 03:14:50 
From: (Mark Mallory)
Organization: Netcom On-Line Services
References:   1
Followups:    1 2
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Andrew Goldfinger ( wrote:
:      I recently flew at 41,000 feet in a commercial airliner (actually FL
: 410, I assume).  According to a friend, at around 42,000 feet free
: flowing oxygen is no longer adequate for maintenance of life, and
: pressure breathing is required.  Therefore, the emergency oxygen system
: (as an SWA flight attendent put it: "these are not party hats") on
: commercial aircraft would not be sufficient.  Does this limit the
: practical ceiling of commercial flights?  What is done for emergency
: oxygen on the Concord?

I flew recently on a BA Concorde, and that was the one question I
was planning to ask the flight crew if I had gotten a chance (which I
didn't get).  But a relevant observation: the passenger cabin
windows are TINY (about the size of a post card).  My guess is that
at least one reason for the tiny windows is to limit the rate of
pressure loss if one fails, such that if an emergency descent is immediately
started from FL 600 the cabin altitude will never get above FL 400 or so.
(Don't know what would happen if a Flight Deck window were to fail.)

Also: at supersonic cruise, one can feel radiant heat coming from the
window; sort of like there was a hot stove sitting right outside!

It's all scary enough to make you ask for *another* glass of champagne. :)