Most jets can do 10,000fpm+. It is going to take a couple of minutes in any
case, that is why it is required for either one pilot to be wearing a mask
or to have quick donning masks immediatly available.

Mike
MU-2

"Montblack" wrote in message
...
("Roy Smith" wrote)
[snip]
I believe that emergency descent capability is one of the factors that
limits allowable operating ceilings. Some aircraft could get higher than
their certified ceilings, but are not allowed to do so because getting
down
to breathable air before the pax suffocated would involve tearing the
wings
off (or some other overspeed disaster).


What is the time limit - 3 minutes? Tell me it's not 4 minutes.

What are planes/jets doing (ft/min) in emergency descents - and how low
must they go to get to "breathable air?" What's the reg for breathable air
out of an emergency descent - 18,000 ft?


Montblack