Originally Posted by
rickair7777
For academic problems, unless otherwise stated, assume the lapse rate stops lapsing at 36,000 and -57* C.
In the real world, that will rarely be the case. But any airliner that can fly that high will do all the math for you.
ya tell my jet that its all academic when Im at 35000 over Siberia and the temp is -68.... lol... when it gets so cold for so long you get fuel freeze caution messages.... lol