RE: HIGH SPEED STALL
There are several types of stalls, probably the term high speed stall is being confused with dynamic stall wich is the one related to 3D flying models for example. High speed stall is related to the Mach critical speed indeed, remember Chuck Yeager flights and how the high speed stall affected the flights of the X1?
Per definition, high speed stall can not happen in the current RC designs, as the air is not compressible at subsonic speeds.
I agree with the fact it is been confused with a "radio hit" .
This thread should probably needs to moved to the Aerodinamics forum.