What happened
On 18 April 2007, an Airbus A319-131, registration G-DBCI, was performing a commercial passenger flight from Amsterdam Schiphol Airport to London Heathrow. During the takeoff roll on Runway 36L, the aircraft experienced a rapid yaw to the right. At approximately 124 KIAS, a significant right rudder pedal input occurred, causing the aircraft to deviate from the runway centerline by 18 degrees.
During the sequence, the commander called out "engine failure," which led the crew to believe a mechanical issue had occurred. The aircraft lifted off at a speed 5 kt below the calculated VR, narrowly avoiding the edge of the runway surface. The crew subsequently maneuvered the aircraft back onto the centerline and continued the flight. Due to the presence of rubber marks on the runway, the crew feared damage to the right main landing gear and elected to perform a precautionary emergency landing at London Heathrow. There were no fatalities and no injuries to the 5 crew members or 112 passengers on board.
The investigation
The investigation examined Flight Data Recorder (FDR) parameters, including rudder deflection, pedal inputs, and aircraft motion. Investigators also inspected the runway at Schiphol, where black rubber deposits were found, matching the aircraft's wheel track.
Technical analysis of the Airbus A319-131 rudder control system, including ground rig testing by the manufacturer, ruled out any mechanical malfunction or hydraulic failure. The investigation also considered the possibility of wake turbulence from a preceding Airbus A330, though no significant evidence was found to support this. Furthermore, the crew's previous training and the psychological impact of the sudden yaw were evaluated to understand the flight deck's response.
Findings
- The aircraft deviated from the centerline due to a full right rudder pedal input.
- The specific cause for the initial rudder pedal movement could not be determined.
- The commander's announcement of an engine failure likely triggered an alarmed response, leading to the application of excessive rudder.
- The crew's decision to continue the takeoff, despite the deviation, was influenced by the lack of a clear 'STOP' command from the commander.
- The presence of tyre marks on the runway was caused by the aircraft's deviation, not by a tyre burst or malfunction.
- The crew's focus was potentially compromised by under-arousal during the benign takeoff conditions prior to the event.