What was found
DURING PREFLIGHT CHECK DISCOVERED, RIGHT AILERON AND TAB DAMAGED. SUBSEQUENT INSPECTION REVEALED NR 8 FLAP TRANSMISSION SPLINED COUPLING RETAINING NUT BACKING OFF CAUSING DAMAGES TO THE ABOVE. REPLACED NR 8 AND NR 7 FLAP TRANSMISSIONS FOR PRECAUTIONARY, TORQUE CHECK ACCOMPLISHED ON FLAP DRIVE COUPLING NUTS. REPLACED DAMAGED RIGHT T/E FLAP MID FLAP, AILERON, AND TAB ASSY. PERFORMED TEST FLIGHT AND AIRCRAFT RETURNED TO SERVICE. (M)