There was thread about this on another message board (that RCU won't let us name). Apparently it is possible but you obvioulsy need to start with a LOT of height just in case as the fixed pitch Corona can't have the blades changed to negative pitch while inverted. You can try it in a simulator by simply flying a simulated CP heli but not adjusting the blade pitch as you do it, that'll give you an idea of what to expect.

Cliff