Saudia Cargo flight 916 suffered a runway excursion during takeoff from runway 21 at Maastricht-Aachen Airport, the Netherlands. The aircraft, a Boeing 747-400F, was cleared for departure from runway 21 for a flight to Jeddah, Saudi Arabia. Shortly after initiating the takeoff roll, the aircraft swerved to the right. The flight crew was not able to regain directional control and the aircraft ran onto the grass where it was brought to a stop. Runway 21 has a Takeoff Distance Available (TODA) of 2500 meters. Conclusion: The runway excursion was caused by the pilot’s inability to maintain directional control under the conditions of prolonged asymmetric thrust that resulted from the loss of thrust on engine #4 at low speed. The loss of engine thrust was caused by a compressor stall. Contributing factors The thrust levers were not retarded immediately after the loss of thrust. Such delays and not following trained procedures have been associated with the phenomenon known as the ‘startle effect’. During training courses in flight simulators, the lessons learned from unexpected situations, such as engine failures, are quite limited as the crews know what to expect.