Incident Overview
During a pushback operation at an airport, a Boeing 737 contacted a lavatory service truck that had positioned itself under the aircraft's tail to service the aft lavatory. The contact occurred shortly after the pushback began, and the handler stopped upon feeling resistance and hearing shouts from the truck driver.
Sequence of Events
The airline uses one-person pushback procedures for B737s at this station. The ground handler conducted a walk-around after the jetway bridge was retracted. After receiving clearance from the flight crew, he leaned over the tow bar for a final check, then boarded the tractor to initiate the push. He did not see the lavatory service truck at any point, and the truck driver did not verbally announce his presence or intentions.
The flight crew activated the rotating beacon just before the aircraft began moving. The lavatory truck driver, who had responded to a service call originally made for another driver, arrived approximately seven minutes before the scheduled departure. When he arrived, the rotating beacon was off, leading him to believe that the pushback was not imminent. He parked his truck under the tail and began servicing the aft lavatory. As the aircraft started moving, it made contact with his truck.
Relevant Procedures
The airline's ramp operations manual stipulates that before approaching an aircraft for last-minute servicing near departure time, personnel must establish positive verbal communication with the pushback tractor driver. In this incident, such communication did not occur.