P=39's and flat spins.

Tumblin' P-39s

I've read the factory findings about the in depth testing done to determine
whether this condition actually existed and if so, how to correct it. No
amount of adjustment resulted in the factory test pilots to duplicate the
manuever described by so many combat pilots. Frustrated, the factory asked the
air corps to provide one or more combat pilots who said they had encountered
'tumble' to come to the factory and assist in recreating the situation
necessary to cause it. After several test flights with various data points
matching what the combat pilots reported, no one was ever able to force a P-39
to tumble. I read this in a 'lessons learned'-type report generated after the
extensive testing had been completed.

v/r
Gordon
====(A+C====
USN SAR Aircrew

"Got anything on your radar, SENSO?"
"Nothing but my forehead, sir."