"Chad Irby" wrote in message
m...

All of the other speed records set up until that time were in horizontal
flight.


Irrelevan't. We're not talking about setting records, we're talking about
achieving supersonic flight.



We lost more than one fighter from compressibility, and it's quite
possible that one or more made it "through" Mach 1 and back.


No, it's not at all possible.