On January 13, 1999, about 1655 Eastern Standard Time, a ground support handler was seriously injured when a cargo door strut on a Boeing 727-200, N785AT, crushed her hand. At the time, the airplane, which was operating as American Trans Air flight 751/752, was parked at a gate at La Guardia International Airport (LGA), New York, New York. The captain, first officer, second officer, 4 flight attendants, and 153 passengers were uninjured. The flight was preparing to depart, operating under 14 CFR Part 121. According to a written statement by the handler, her supervisor told her to close one of the cargo doors. The handler wrote: "The baggage compartment doors are held wide open above and perpendicular to the fuselage of the 727 by an expandable metal bar. The expandable metal bar is connected to the inside and left hand side (looking at the bar from the inside) of the door and it latches into a notch on the right hand side (looking at it from the outside) of the fuselage of the airplane. I attempted to close the aft baggage compartment door, but when I tried to undo the latch, the bar violently popped out of the notch. The door came crashing down at high velocities, the bar swung into the belly of the aircraft with my hand. With that, the bar penetrating, crushing and tearing the left palm between the pointer finger and thumb, also injuring arm/shoulder/neck." The accident was not reported by the airline. It was reported to the Safety Board by the injured handler in August 1999, and confirmed in September 1999. According to the airline's director of safety, the handler had worked for Signature Flight Support, which provided the ground support to the airline at La Guardia. The airline was unaware of the accident because Signature had not reported it. In a letter to the airline dated August 18,1999, the handler's supervisor wrote that the handler had reported to work on the day of the accident after recuperating for a couple of days, from a lower back injury. She was going to be on light duty, and was instructed to only wing walk and assist with radio communications. The supervisor also stated that the handler was signed off to work on the ramp and on the Boeing 727, and that she had "received on-the-job training for this particular task." In another statement dated January 13, 1999, the supervisor stated that when he asked the handler what happened, she said that the door came down on her while she was closing it. "She was holding the bar that braces the door up with her right hand. It probably came down on her too hard, and she couldn't handle it...." In an undated statement, a witness wrote that he saw the handler pull out the bar that secured the baggage door when it was it open. "She lost control of the bar, turn[ed] side way[s] to brace from the impact of the aircraft door. The door hit her and she fell to the ground...." The Boeing 727 maintenance manual excerpt provided by the airline stated that the aft cargo door was a plug-type, outward-upward opening door. The door was equipped with two balance mechanisms to counterbalance the weight of the door to facilitate door opening. The forward balance mechanism had a rotary snubber to prevent the door from opening or closing with excessive force. A support strut was also present, to secure each door in the fully open position. The maintenance manual also stated that the cargo door would have been closed "by removing the support strut from the fuselage fitting, telescoping the strut and stowing it in the slotted bracket by the door....The cargo door then swings down...." The ground service manual in use included the following procedure: "Pull cargo door down using Support Strut." According to the airline's maintenance records, a discrepancy was written up on the cargo door, dated December 25, 1998. It stated: "Aft cargo door heavy to open." The corrective action was: "Found fwd counterbalance hinge loose from mount. Resecured counterbalance hinge as required. Ops check good at this time." On February 7, 1999, the following discrepancy was written: "Aft cargo door heavy when opening." The following day, the corrective action was: "Adjusted cable tension on fwd balance as required...." The airline also reported that on the day of the accident, a daily service check was performed on the airplane. Part of the service check required a visual inspection of the cargo bay area, which required the mechanic to open, and then secure, the cargo bay door.