QUESTION:
I wanted to know if the K.A.O. is able to fly above an altitude of 41,000
feet?  If not, why?

ANSWER from Terry Rager on October 30,1995:
The KAO can fly higher than 41,000 ft. Ten years ago we flew about 10% of
our flights up to 45,000 ft. and sometimes we still do. There are a couple
reasons for not flying at higher altitudes. First, the air at higher
altitudes is thinner so the engines have to work much harder to propel the
airplane fast enough to create the amount of lift required to stay at that
altitude. We have to be very light to fly that high. By the time we have
burned off enough fuel to get to 45,000 ft., we have to start down about
45 minutes later. Secondly, the airplane is less stable at higher
altitudes and "wallows" around, like a boat on a rough lake. This makes
the telescope work harder at staying steady and the astronomers have a
more difficult time staying on their object. Lastly, airplanes must be
designed to come down as well as go up. Because we carry passengers the
airplane must be designed to descend to a safe altitude, fast enough, so
that no one would be seriously injured if we had a rapid decompression and
lost all pressurization in the cabin. That is a limitation on all
commercial aircraft. 

I hope this answered you question. Thanks!!!

Terry Rager,Project Pilot, KAO