What happened
On the afternoon of the accident, an international flight scheduled to travel from Rome, Italy, to Athens, Greece, began its departure sequence. The aircraft commenced its takeoff roll on runway 25 at 13:07 GMT. During the acceleration phase, once the aircraft had exceeded 80 knots, the pilot-in-command observed that the No. 4 engine pressure ratio gauge indicated zero thrust. Almost simultaneously, a warning light appeared indicating that the thrust reverser for the No. 2 engine had deployed.
Because the aircraft had not yet reached its V1 decision speed, the pilot elected to abort the takeoff and assumed control of the aircraft. As the plane moved approximately 800 to 900 meters past the runway threshold, it began to decelerate, though at a rate significantly lower than anticipated. During this process, the aircraft veered sharply to the right, causing the right landing gear to scrape the edge of the runway. In an effort to correct the directional deviation and return to the centerline, the crew reduced reverse thrust on both right-side engines.
The aircraft failed to stop within the runway limits and collided with a maintenance pavement roller located on taxiway 16/34. The impact caused the No. 4 engine to strike the vehicle, leading to a fuel leak. After traveling an additional 260 meters, the aircraft came to a halt while on fire. A sequence of explosions followed, and the aircraft was consumed by flames and destroyed. The accident resulted in 49 fatalities (comprising five crew members and 44 passengers) and 24 injuries, several of which were serious.
Findings
Investigations revealed that a malfunction occurred within the No. 2 engine's reverse thrust system, specifically involving a disconnected duct that caused a loss of pressure in the pneumatic mechanism for the clamshell door. This defect was not detectable via cockpit instruments and caused the engine to produce significant forward thrust despite the levers being set to reverse. The collision with the maintenance roller ruptured the fuel feed tube for the No. 4 engine, igniting the spilled fuel. Additionally, a blocked valve prevented proper drainage from the surge tank, allowing fuel to escape through the vent scoop toward the wing fire. The presence of an explosive fuel-air vapor mixture within the tanks contributed to the series of explosions observed during the event.