What was found
(CAN) DURING ROUTINE MAINTENANCE THE LEFT HAND FIXED MAIN LANDING GEAR DOOR WAS FOUND TO HAVE A BROKEN FORWARD LOWER ATTACHMENT STUD. THE POINT OF FRACTURE DISPLAYED PROGRESSIVE 'TIDE MARKS' OF CORROSION WHICH INDICATED AN EXTENDED PERIOD OF FAILURE. THE DOOR OPENING SHOWED EVIDENCE THAT THE DOOR'S AFT EDGE HAD CONTACTED THE UNDERSIDE OF THE WING. THIS CONDITION WOULD ALLOW THE FORWARD EDGE OF THE DOOR TO BE EXPOSED TO AIR LOADING DURING FLIGHT.