What happened
While preparing for departure at its origin airport, baggage was loaded into a Douglas DC-9-31 by contract ramp personnel. During the climb through approximately 20,000 feet mean sea level, the flight crew heard a loud pop, followed by a sudden cabin depressurization. The crew immediately donned oxygen masks and diverted to the nearest suitable airport, where they completed an uneventful landing.
The investigation
A postflight inspection of the aircraft revealed a fuselage skin tear measuring 12 inches by 5 inches, located approximately 6 feet forward of the forward cargo door. The investigation determined that during the baggage loading or off-loading process, the engine of the belt loader ceased operating. To move the equipment, the senior of three ground agents attempted to push the belt loader away from the aircraft using a luggage tug. During this maneuver, the cab of the tug made contact with the fuselage.
Findings
Following the impact, the senior ground agent instructed another employee involved in the flight not to report the incident. The investigation concluded that the actions taken by the senior ground agent were contrary to the instructions provided in the company's training handbook and operation manual.