What was found
DURING CLIMBOUT FROM BGTL DOOR NOT LATCH LIGHT ILLUMINATED AFTER RAISING MAIN LANDING GEAR. THE CREW ACCOMPLISHED COM PROCEDURE AND THE LIGHT STAYED ON. BOTH ALTERNATING MAIN LANDING GEAR LIGHTS WERE OUT AND TESTED GOOD. THE CREW LANDED IN KTOL WITHOUT FURTHER INCIDENT. MAINTENANCE REPLACED LEFT UPLATCH CYLINDER. JACKED AIRCRAFT AND SWUNG GEAR NUMEROUS TIMES. OPERATIONAL CHECK GOOD IAW DACO MAINTENANCE MANUAL 32-30-0. AIRCRAFT WAS RETURNED TO SERVICE.