Investigation Summary
The accident was initiated by a mechanical failure in the right engine's thrust reverser system, which deployed while the aircraft was in a high-power takeoff climb. The Fokker 100 is equipped with a safety mechanism designed to automatically pull the throttle lever to the idle position if a reverser deploys in flight, preventing dangerous asymmetrical thrust. However, the crew had not been adequately trained on this specific failure mode or the automatic throttle movement associated with it. Believing the throttle was slipping, the first officer manually forced the lever forward twice. The second time, the force applied by the pilot against the opposing force of the safety actuator caused the throttle cable to part at the turnbuckle connection. With the cable broken, the safety system could no longer retard the engine, and the pilot successfully pushed the right engine to full takeoff power. Because the reverser buckets were still deployed, the engine produced maximum reverse thrust. The aircraft entered a severe right-wing-down roll that could not be corrected at low altitude, striking several houses in the densely populated Jabaquara district.
Final Conclusions
The investigation concluded that the primary cause was the uncommanded deployment of the right engine thrust reverser, compounded by the crew's lack of specific training regarding the aircraft's automatic protection systems. The physical override of the safety mechanism led to the failure of the throttle cable, which removed the final protection against catastrophic asymmetrical thrust. The crash resulted in 99 total fatalities: 90 passengers, 5 crew members, and 4 individuals on the ground.
Video Analysis
Air Crash Investigation [English] - Carnage In Sao Paulo — A detailed look at the technical failures and crew actions that led to the crash of TAM Flight 402 in a residential area of São Paulo.
If playback is blocked, the owner has disabled embedding — use the link above.
Airframe & Maintenance
Crew Experience
Captain
Graduated from Mogi-Mirim Airclub in 1987.
First Officer
Graduated from Rio Claro Airclub in 1988.
Systems & Failure Modes
Thrust Reverser Safety Actuator
A mechanical system designed to automatically pull the throttle lever to the idle position if the thrust reverser deploys unexpectedly, preventing high-power reverse thrust.
Rolls-Royce Tay 650-15 Engines
The turbofan engines equipped with clamshell-style thrust reversers; the right engine's reverser deployed due to a mechanical failure during the takeoff roll.
Secondary Lock Actuators
Components intended to keep the thrust reverser stowed; the units on PT-MRK performed significantly below safety standards during post-accident testing.
Thrust Selector Valve
A valve that could be moved with less than 2% of normal functioning pressure when de-energized, contributing to the unstable state of the reverser system.
Interesting Facts
- 01The aircraft was painted in a special blue livery commemorating TAM's 'Regional Airline of the Year' award.
- 02The crash killed all 95 people on board and 4 people on the ground, totaling 99 fatalities.
- 03The Fokker 100 safety system was designed to prevent the exact scenario that occurred, but it was overridden by pilot input.
- 04The first officer had only 160 hours of experience on the Fokker 100 type at the time of the accident.
- 05The aircraft, MSN 11440, was manufactured in 1993.
Safety Actions & Advisories
Thrust Reverser Training
Aviation authorities and Fokker mandated enhanced training for pilots to recognize and respond to uncommanded thrust reverser deployment without overriding automatic safety protections.
Hardware Modifications
Recommendations were made to improve the reliability of the thrust reverser locking mechanisms to prevent uncommanded deployment.
Known Controversies & Unanswered Questions
Airworthiness Certification Dispute
Reference ↗The CENIPA investigation found that the Fokker 100's thrust reverser system, specifically the 'Post-Mod' version, did not meet the airworthiness requirements of FAR 25.1309 and 25.933. The system allowed for power higher than idle to be applied while buckets were partially open and inhibited critical warning lights (RSVS UNLK) during the most vulnerable phase of flight (between 80 knots and 1,000 feet).