What happened
On the evening of June 17, 2004, a Swiftair Fairchild SA227-AC (registration EC-GXE) was performing a non-scheduled domestic cargo flight from Valencia Airport to Madrid. The flight crew, consisting of two pilots, was preparing for takeoff on runway 30 under visual meteorological conditions. The aircraft was utilizing water/methanol injection to achieve takeoff power.
During the takeoff run, once the aircraft reached an airspeed of approximately 85 knots, the pilot flying released the Nose Wheel Steering (NWS) power lever button. Immediately following this action, the aircraft began to deviate toward the right side of the runway centerline. The captain took control and initiated a rejected takeoff procedure; however, the aircraft could not be maintained on the runway. The plane exited the right edge of the runway, traveling approximately 3 and a half hundred meters across flat terrain. The aircraft eventually skidded out of control and came to a stop 75 meters from the runway centerline. There were no fatalities and no injuries to the crew.
The investigation
The investigation examined the aircraft's mechanical systems, maintenance history, and the sequence of events recorded by the flight data recorder. Investigators reviewed the NWS system configuration, noting that while the aircraft had received certain service bulletins, it lacked more recent updates regarding the NWS amplifier and hydraulic valves.
Maintenance records and post-incident inspections were analyzed. The investigation looked into the possibility of asymmetrical engine power, wind conditions, or external factors such as wake turbulence from a preceding Boeing 757. The investigation also reviewed the cockpit procedures outlined in the Airplane Flight Manual (AFM) regarding the use of the NWS button during takeoff.