TAM Transportes Aéreos Regionais Flight 402
PT-MRK, the aircraft involved in the accident at the same airport on March 1996, about 7 months prior to the crash.
|Date||31 October 1996|
|Summary||Mechanical failure; uncommanded deployment of thrust reverser after takeoff.|
|Site||São Paulo, Brazil|
|Fatalities||99 (all aboard, plus 3 on the ground)|
|Aircraft type||Fokker 100|
|Operator||TAM Transportes Aéreos Regionais|
TAM Transportes Aéreos Regionais Flight 402 was a scheduled domestic flight from Congonhas-São Paulo International Airport in São Paulo, Brazil to Recife International Airport in Recife via Santos Dumont Airport in Rio de Janeiro. On 31 October 1996, at 08:27 (UTC-3), the Fokker 100 operating the route suffered uncommanded thrust reverser deployment on its starboard engine while climbing from Congonhas, making the aircraft stall, roll beyond control to the right, strike two buildings and crash into several houses in a heavily populated area only 24 seconds after takeoff, killing all 96 people aboard as well as three on the ground. It is the fourth deadliest accident in Brazilian aviation history, the second at the time.
The aircraft involved, a Fokker 100, was registered PT-MRK and wore a special promotion blue livery on its fuselage with the inscription "Number 1", in reference to a "Regional Airline of the Year" award given to TAM Transportes Aéreos Regionais by Air Transport World magazine. The Aircraft has been Acquired by TAM In April 1995 and was previously owned by Indonesian defunct airline namely Sempati Air which was owned by president Suharto. The aircraft had made its first flight 7 years and nine months earlier, on 8 February 1993, and had accumulated 8,171 flying hours.
Sequence of events
At 08:25 the flight crew, captain José Antônio Moreno and first officer Ricardo Luiz Gomes Martins, received clearance for takeoff from runway 17R. Wind was given as 060 degrees. The throttles were advanced for takeoff thrust at 08:26:00. Ten seconds later a double chime was heard. The captain then warned "O autothrottle tá fora" ("Autothrottle is off"), and the first officer adjusted the throttles manually, informing the captain "Thrust checked", thus confirming that the takeoff power had been adjusted and verified. At 08:26:19 the airplane accelerated through 80 knots, with the first officer indicating "V one" at 08:26:32. Two seconds later the airplane rotated at a speed of 131 knots.
At 08:26:36 the air/ground switch transited from "ground" to "air". When the airspeed was increasing to 136 knots and the airplane was climbing at an angle of 10 degrees, a shock was felt and the engine pressure ratio (EPR) of engine number 2 (starboard) dropped from 1.69 to 1.34, indicating loss of power. In fact, the engine thrust reverser had deployed. An eye witness confirmed to have seen at least two complete cycles of opening and closing of the number 2 thrust reverser buckets during the short flight.
The loss of power on the starboard side caused the aircraft to start a roll to the right and the captain applied left rudder and left aileron inputs to counteract the movement. The first officer advanced both thrust levers, but they retarded again almost immediately, causing the power of the number 1 (port) engine to drop to 1.33 EPR and engine number 2 to 1.13 EPR. Obviously not aware of the malfunction, both crew members then vainly forced the thrust levers forward again. At 08:26:44 the captain ordered the autothrottle to be disengaged. One second later the number 2 thrust lever retarded again and remained at idle for two seconds, the airspeed fell to 126 knots. At 08:26:48 the first officer announced that he had disengaged the autothrottles and then jammed the number 2 thrust lever fully forward again. Both engines now reached 1.72 EPR.
With the thrust reverser deployed, this maneuver made the airspeed decrease even faster, at 2 knots per second. At 08:26:55 the stick shaker activated, warning of an impending stall. The airplane rolled to an irrecoverable 39 degree bank angle and the ground proximity warning system activated. Seven seconds later the airplane impacted a building and crashed into a heavily populated neighborhood.
- Accident description at the Aviation Safety Network
- Reproduction animation of TAM Linhas Aéreas Flight 402
- Image of the Number 1 Livery from Airliners.net