What happened
During the takeoff roll on runway 04L, the aircraft began to deviate toward the left side of the runway. At the time of the incident, the runway surface was covered in patches of snow and ice, with winds recorded at 11 knots from 330 degrees. The deviation occurred before the first officer could communicate the 80-knot airspeed milestone. The Boeing 747 subsequently exited the left side of the runway, striking electrical transformers and various signs.
Findings
Investigations into the accident identified that the captain had applied excessive control to the nosewheel steering via the tiller. Furthermore, the pilot failed to provide enough or sufficiently timely right rudder input to correct the directional deviation. It was also noted that the captain briefly ceased an attempt to abort the takeoff by increasing forward thrust before the aircraft left the paved surface.
Analysis indicated that the existing Boeing 747 operating procedures did not offer enough instruction regarding the risk of losing directional control at low speeds when using the tiller on contaminated runways. Additionally, the flight manual lacked clear guidance on the appropriate timing for rejecting a takeoff once a loss of control is detected. The investigation concluded that inadequate flight manual guidance and procedures regarding takeoff rejection and tiller use contributed to the event, suggesting a need for better simulator training fidelity for slippery runway conditions.