As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(AUS) ENGINE FAILED. INITIAL INVESTIGATION REVEALED A FAILURE OF THE MAGNETO DRIVE SYSTEM. DURING AUTO ROTATION AND LANDING, ONE MAIN ROTOR BLADE CONTACTED THE TAILBOOM. FURTHER EXAMINATION FOUND THE CRANKSHAFT IDLER GEAR DAMAGED. SUSPECT CAUSED BY LOSS OF TORQUE ON THE STUD HOLDING THE CRANKSHAFT IDLER GEAR POSSIBLY CAUSED BY THREAD BEING STRIPPED DURING ASSEMBLY.