What was found
ENG WOULD NOT START. INVESTIGATION FOUND ACCESSORIES AND STARTER MOTOR WOULD TURN BUT ENGINE N1 AND N2 ROTORS DID NOT. FOUND HORIZ DR SHAFT (PN 3070201-11) HAD UNCOUPLED FROM ACCY GEARBOX DUE TO RETAINER RING (M27426-3116A) BECOMING UNLOCKED AND ALLOWING MOVEMENT OF SHAFT. PRIOR TO 2000, RETAINER RINGS NOT ROUTINELY REMOVED FROM TRANSFER GB HSGS. IF REMOVED, WERE PERMITTED TO BE REUSED, ONLY BEING REPLACED (ON CONDITION). AFTER 11/2000, ALL ENG UNDERGOING MPI OR GREATER INSP ARE REQUIRED TO HAVE RETAINER RING REMOVED AND REPLACED NEW. REPLACEMENT IS NOW MANDATORY AND ROUTINE.