The throttle was in the full forward position too, indicating full power was being applied, but again might have been from impact.  Adding full power could accelerate the snap roll.  You are correct in your assesment; however another outside possibility would be wake turbulance.  This is what the NTSB is sorting through and will release preliminary findings soon.

Ron Galbraith

"...upside down at about 45 degree angle" sure sounds like a full stall with a snap roll, just like mine would do if I didn't know how to recognize and recover from the situation before it turned so bad. What else could do it?

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