What was found
LEVEL FLIGHT, THE TAIL ROTOR DRIVESHAFT STARTED SLIPPING. TAIL ROTOR DRIVESHAFT SPLINES STRIPED. ON FRONT HALF OF SHAFT, STUDENT ENTERED AN AUTOROTATION AND AIRCRAFT LANDED HARD AND RECEIVED SUBSTANTIAL DAMAGE.
As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
LEVEL FLIGHT, THE TAIL ROTOR DRIVESHAFT STARTED SLIPPING. TAIL ROTOR DRIVESHAFT SPLINES STRIPED. ON FRONT HALF OF SHAFT, STUDENT ENTERED AN AUTOROTATION AND AIRCRAFT LANDED HARD AND RECEIVED SUBSTANTIAL DAMAGE.