What happened
On the scheduled flight from Hong Kong to Bangkok, which included an intermediate stop in Saigon, a Boeing 747 (implied by engine count/context) was performing a takeoff roll on runway 13. The crew configuration included a co-pilot in the left-hand seat, a pilot-in-command in the right-hand seat for performance monitoring, and a check captain in the jump seat.
At approximately 10:34, the aircraft began its takeoff roll. During the acceleration phase, once the aircraft reached just under 120 kt, the crew experienced intense vibrations. In response to these vibrations, the co-pilot initiated an aborted takeoff by reducing power and applying maximum braking and spoilers. Although the power levers were closed promptly, there was a brief delay of several seconds before reverse thrust was engaged.
The aircraft continued to accelerate slightly after the abort command until reaching 137 kt before deceleration began. During the braking process, the crew noted that the antiskid system did not appear to be cycling. The aircraft initially maintained its path but then began veering toward the right. Despite attempts to correct the deviation using opposite rudder and differential braking—which eventually required releasing the right brake entirely—the aircraft could not be stabilized. The plane exited the runway, crossed a grass strip, and passed through a seawall. Upon impacting the sea, the four engines separated from the airframe, and the fuselage sustained structural fractures. The accident resulted in 1 fatality and 33 injuries.
Findings
Investigations determined that the primary cause of the loss of directional control was the separation of the right nose-wheel tread. Additionally, the aircraft was unable to stop within the available runway distance due to a combination of factors: the necessity of using differential braking, reduced performance, an increase in tailwind, and an aircraft weight that exceeded the parameters used for takeoff performance calculations.