As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE IN FLIGHT, PILOT NOTICED SUDDEN VIBRATION IN TAIL ROTOR PEDALS AND CYCLIC. LANDED THE AIRCRAFT AND CALLED TECHNICIAN. TECHNICIAN CHECKED THE TAIL ROTOR AND SURROUNDING AREA. CHECKED TAIL ROTOR GEAR BOX FOR SECURITY AND ALSO THE TAIL ROTOR CHIP DETECTOR AND FOUND NOTHING. ASKED THE PILOT TO START THE ENGINE AND THEN HEARD A VERY LOUD WHINING SOUND COMING FROM THE TAIL ROTOR GEAR BOX. THE TAIL ROTOR GEAR BOX WAS THEN REMOVED AND SENT FOR REPAIR.