What was found
UPON RECEIPT OF ENGINE FOR MAINTENANCE, IT WAS DISCOVERED THAT THE POWER TURBINE LOCKNUT HAD LOST TORQUE AND BACKED OFF OF THE POWER TURBINE TIE BOLT. THE PROBABLE CAUSE WAS LOSS OF TORQUE. A SPECIAL INSPECTION WAS INITIATED TO INCLUDE INSPECTING RUN-ON TORQUE. A SPECIAL INSPECTION WAS INITIATED TO INCLUDE INSPECTING RUN-ON TORQUE AND PERFORMING AN NDT INSP OF ALL LOCKNUTS IN INVENTORY AND THOSE UNDERGOING MAINT. ALL LOCKNUTS CURRENTLY INSTALLED ON AC WILL BE REPLACED AND THOSE LOCKNUTS WILL BE RETURNED TO REPAIR STA FOR INSP. MFG WILL BE NOTIFIED OF INCIDENT IMMEDIATELAY. (K)