JT,
I cannot argue with any of your maths, and all this stuff certainly has little relevance to a practicing ATPL. But to an ATPL student it is essential stuff. If KK is studying for his technical exams, or has any thoughts of doing so in the future, researching this kind of stuff can be nothing but helpful.
Similarly, the nomogram I referred to will be of little value in the cockpit, but if he wants to try to devise his own shortcut equations, or modify any he gets from reference books, it will enable him to test them without lots of button pushing.
[ 14 February 2002: Message edited by: Keith Williams. ]</p>