I was interested to read that you too lost a PC9 due to elevator flutter! Mine was coming of the bottom of a loop then a loud drumming noise was heard and then no elevator control, straight in!!!! Total right off, even damaged my receiver! I looked through the wreckage and the metal quick link complete with security tube still over it had ripped out of the control horn, unreel! This was it's first flight after about 8 mins would you believe? Shame as it flew perfectly with no trim adjustments needed at all.
As i was well peed off i wrote to the distributors JP Distribution U.K. and after a couple of letters, returning the tail of the plane and a conversation with the MD, as a jesture of goodwill they gave me credit to the full retail cost of the kit! It was never decided what caused the flutter, but my best guess is that the pushrod had warped after being fitted and became flexible. Who knows, but it is definately a kit problem, factory fitted supported pushrods would certainly cure it.

Regards,

Dave Weatherhead (England)