ceiling figures are based on the actual performance
of the aircraft

In theory, "service ceiling" is the altitude at which an aircraft can
no longer climb at 100 feet per minute. "Absolute ceiling" is the
altitude at which it can no longer climb at all.

However, it is an honored tradition to hand out misleading ceiling
information. The B-36 had a service ceiling I believe in the high
30Ks, but was known to have flown at 50K and above.

I'm amazed at the notion of a 50K-plus service ceiling being thrown
around here. This modern fighters must be more like rockets than jet
planes. In the 1950s-1960s the only planes that could get up that high
were semi-gliders like the B-36 and the U-2.

What is the practical altitude limit at which a jet can no longer
ingest enough air to keep it operational?

all the best -- Dan Ford
email: (requires authentication)

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com