What was found
ICT - DURING CRUISE, NR 1 ENGINE, S/N 3210, SPOOLED DOWN. SHUT DOWN ENGINE. FOUND INTERNAL MALFUNCTION IN N-2 ACCESSORY GEARBOX, MFG P/N 758300. CHANGED ENGINE AND ENGINE OPERATION CHECKED NORMAL. INVESTIGATION OF SPOOL DOWN OF NR 1 ENGINE, REVEALED A BUSHING, P/N 783310, ALLOWED THE INPUT GEAR TO SHIFT CAUSING RAPID TOOTH WEAR, RESULTING IN GEARBOX FAILURE. GEARBOX REPAIRED AND RETURNED TO SERVICE. (M)