What happened
During the takeoff roll, the captain observed that the control forces required to pull the yoke aft were significantly higher than expected, indicating the aircraft was not responding to rotation commands at the current speed. In response to this difficulty in rotating the aircraft, the pilot initiated an aborted takeoff. As the aircraft continued down the runway, it became apparent that the remaining distance was insufficient to come to a complete stop. To prevent a collision with vehicles on a nearby highway, the pilot steered the aircraft toward the right side of the runway.
During the excursion, the aircraft struck ILS equipment, which caused the landing gear to collapse. The impact resulted in all four engines being torn from the airframe, and the aircraft was subsequently consumed by fire. There were no fatalities reported in the incident.
Findings
Investigations determined that the flight engineer had incorrectly calculated the takeoff speeds and the horizontal stabilizer trim settings. The calculations were based on a takeoff weight of 242,000 lbs, whereas the actual weight of the aircraft was 342,000 lbs. This discrepancy meant that the rotation speed used was 28 knots slower than what was required for the actual weight. Crucially, neither the captain nor the first officer had verified the takeoff data prepared by the flight engineer. Additionally, investigators identified deficiencies in the operator's training programs and noted issues regarding the scheduling of crew members with limited experience.