I've read that the U2 (or is it U-2) has a 4 knot speed range at altitude.
Too fast, you get mach buffet-too slow, you stall.

mike

"Mxsmanic" wrote in message
...
mike regish writes:

I've only heard of the "coffin corner" in reference to helicopter flight.

The U-2 is famous for its coffin corner, and some other aircraft have
one as well.

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