As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
IN FLIGHT TRANSMISSION PRESSURE DROPPED TO ZERO, RETURNED TO NORMAL AND BACK TO ZERO IN A 15 MINUTE FLIGHT. INSPECTION BY MAINT REVEALED THE NR 8 TAIL ROTOR DRIVE SHAFT HAD FAILED. A WO WAS OPENED FOR REPAIR OF THIS AIRCRAFT. REMOVED AND REPLACED TRANSMISSION OIL GAUGE. (K)