Narrative
Two employees began a pushback procedure for an airplane preparing for departure. One employee operated a Lektro electric pushback vehicle, while a second employee served as a wing-walker on the left side of the airplane. As the pushback started, the vehicle moved into a jack-knife position toward the airplane's right engine, which was running, and the propeller was turning in the "feathered" position. At that point, the Captain and First Officer signaled for ground personnel to halt the pushback. However, the vehicle continued to turn about the nose of the airplane until the wing-walker ran to the vehicle and stopped the movement.
The original operator then exited the vehicle on its left side, toward the right wing, and began walking backwards toward the turning propeller. After a few steps, the employee was struck by the propeller "at least twice" before falling to the ground.
Investigation
According to the company's push-out/towing procedures, "when the headsets are inoperative or the ramp has been advised of lightning in the area, hand signals will be used for communication between ground personnel and the Captain and an additional ground agent will be required." The operator of the pushback vehicle and the wing-walker were not wearing ground-to-cockpit headsets at the time of the accident because the headsets were not working properly. The operator reported that it was the first time the injured employee had operated the pushback vehicle alone.