As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(AUS) MAIN ROTOR TRANSMISSION INPUT PINION GEAR FAILED. GEAR TEETH STARTING TO BREAK DOWN WITH DISTINCT WEAR PATTERN AND PITTING ON THE FLANK OF ALL GEAR TEETH AND ADVANCED BREAKING DOWN OF SOME OF THE TEETH. METAL CONTAMINATION OF TRANSMISSION.