What happened
A commuter airplane was parked at the gate with its engines stopped, chocks in place, and the airstair door open. At the time of the incident, the crew of three was seated in the cockpit completing paperwork, and 50 passengers were seated on board.
The incident involved two baggage tractors. One tractor, identified as DH4, had experienced a mechanical breakdown. The operator of another tractor, DH65, was requested to push the disabled unit to the end of the ramp to await service. As DH6 began pushing DH4, the disabled tractor steered to pass approximately 15 to 20 feet to the left of the aircraft.
As DH4 entered the service road and began turning right to head west, DH65 had not yet entered the service road and continued traveling southwest for several additional feet. During this maneuver, the left side of the front hitch on DH65 made contact with the right side of the rear hitch on DH4. This hitch contact jerked the front of DH65 to the right, causing the driver to be pitched halfway off the left side of the vehicle. As the driver fell, his hand pulled down on the steering wheel and his foot pressed the accelerator pedal, causing DH65 to veer into the nose of the airplane.