What happened
During preparations for a flight to France, an Air France Boeing 747-200 cargo aircraft was being serviced at gate 111 at Montreal International (Mirabel) Airport. As the engine start-up sequence concluded, the flight crew received taxi clearance from the apron controller. Shortly after beginning to move, the aircraft's right wing main landing gear struck a ground power unit (GPU) vehicle that was still positioned under the wing.
The impact pushed the vehicle approximately three feet. The captain immediately halted the aircraft, preventing further movement. There were no injuries reported, though the aircraft sustained minor damage to a wheel-well door and two main wheel tires.
The investigation
The investigation examined the ground handling procedures and the communication between the flight crew and ground staff. It was established that while both Air France and the ground handler, Air Canada, had procedures requiring all equipment to be clear of the aircraft's safety perimeter before the "all clear" signal, local practice at Mirabel involved keeping the GPU vehicle near the aircraft for convenience.
Investigators found that the ground handler in charge of communications had informed the pilots that the aircraft was clear, despite the GPU vehicle still being present. Furthermore, the flight crew was distracted by non-standard radio phraseology used by the controller, which they initially misheard. The investigation also noted that the signalman's position was at the edge of the co-pilot's peripheral vision due to the airport's open ramp layout, and his high-visibility gloves were faded and dirty, reducing their effectiveness.
Findings
- The flight crew advanced the aircraft after misinterpreting a hand signal from the signalman as a signal to proceed.
- The ground handler incorrectly communicated to the flight crew that the aircraft was clear while the GPU vehicle remained under the aircraft.
- The GPU vehicle stalled when the ground handler attempted to drive it away from the aircraft's path.
- The signalman's fluorescent gloves were faded and dirty, which may have hindered visibility.
- Non-standard phraseology used by the apron controller distracted the flight crew during their ground checklists.
- Local ground handling practices at Mirabel deviated from the established safety procedures of both the air carrier and the ground handling company.
Safety action
Following the occurrence, Air France amended its General Line Manual to ensure more accurate ground-to-aircraft communications and implemented stricter verification of crew compliance. Air Canada also updated its procedures at Mirabel Airport to ensure all vehicles are moved clear of the aircraft before the signalman provides the "all clear" signal to the crew.