NASA uses a sylized value of 1,000 ft/sec as Mach 1 at the very high (Peak
Heating Region) altitudes.

I wish the people in the local cocktail circuit were more tuned in to
air & space. Then I could ambush somebody with this factoid.

all the best -- Dan Ford

Well, Dan you just have to wait till someone says, "Boy, we've been
having some hot weather recently!"

Whereupon you respond, "Speaking of 'hot,' did you know that at the
Peak Heating Region.....

vince norris