What was found
ROTOR SHAFT SHEARED OFF JUST AFT OF SEAL RUNNER BUSHING. THE BREAK IN THE SHAFT APPEARS TO HAVE BEEN CRACKED FOR SOME TIME. THIS ENGINE HAD MAJOR OVERHAUL 441 HOURS AGO FOR PROP STRIKE. THE RIGHT MAGNETO IS DIRECT DRIVE (NO IMPULSE), AND SUSPECT THE SHAFT FAILURE WAS DUE TO SUDDEN STOP OR TORSIONAL SHOCK TO MAGNETO ROTORSHAFT. THE ENGINE HAD SUDDEN STOPPAGE PREVIOUSLY, AND PROP WAS SEVERELY CURLED THE FIRST STRIKE. LOGS SHOW LEFT MAG TO BE ORIGINAL EQUIPMENT.