As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) INSPECTION FOUND DRIVE SPLINES SHEARED OFF. HELICOPTER HAS NO HISTORY OF TAIL ROTOR STRIKE. INVESTIGATION INCLUDING ENGINEERING FAILURE ANALYSIS OF PART. OPERATORS FLEET INFORMED AND INSPECTED FOR SIMILAR PROBLEM. WILL FORWARD RESULTS.