The world record for helos is held by a French helicopter called a Lama at
something like FL410. Pretty unusual to hear of any flying above 10,000. I
don't think that I have ever seen a preasurized helicopter, certainly never
ridden in one.

Mike
MU-2

"Robert M. Gary" wrote in message
om...
The other day I heard on Center "Helicopter 1234 with you Flight Level
340". This can't be possible, can it? Is there enough air up there for
the rotors to be effective?
-Robert