Accident Overview
On September 29, 2006, a Boeing 737-8EH (registration PR-GTD) operating as Gol Transportes Aéreos Flight 1907 from Manaus to Rio de Janeiro collided in flight with an Embraer EMB-135BJ Legacy (registration N600XL) over the Brazilian Amazon. The Boeing 737, carrying 6 crew and 148 passengers, was en route to Rio de Janeiro with a planned stop in Brasília. The Legacy, with 2 crew and 5 passengers, had departed São José dos Campos bound for Manaus and then Fort Lauderdale, Florida.
The Boeing 737's last radio contact was at 19:53 UTC with Amazonic Area Control Center (ACC AZ), after which it was instructed to contact Brasília ACC (ACC BS) at NABOL, but the call was not made. At 20:14 UTC, ACC AZ received a relay from Polar Air Cargo 71 that the Legacy declared an emergency due to flight control difficulties and was diverting for an emergency landing at SBCC (Campo de Provas Brigadeiro Veloso in Novo Progresso, Pará). After landing, the Legacy crew reported colliding in flight with an unknown object. The Legacy sustained damage to its left wingtip and left elevator. The wreckage of the Boeing 737 was found the next day in a forested region of Peixoto de Azevedo, Mato Grosso. All 154 occupants of the Boeing 737 perished.
Investigation Findings
The official investigation identified human factors and active failures related to the Legacy crew and air traffic control. For the Legacy crew, active failures included inadequate flight planning, insufficient knowledge of the flight plan, lack of a pre-departure briefing, unintentional change of transponder setting, failure to prioritize attention, failure to perceive transponder non-transmission, delay in recognizing communication problems, and non-compliance with communication failure procedures. Low situational awareness (airmanship) was considered a relevant factor.
The breakdown in situational awareness began during flight preparation, which the crew considered routine. Contributing factors included: inadequate planning influenced by habitual procedures; haste to depart and passenger pressure hindering flight plan knowledge; poor crew dynamics with lack of task division and monitoring; and lack of specific Standard Operational Procedures (SOPs) from the company for that aircraft model. The inadvertent transponder shutoff was possibly due to the pilots' inexperience with the aircraft's avionics. The crew did not notice the transponder was off due to reduced awareness of TCAS alerts, nor did they realize they had a communication problem. They flew at a non-standard flight level for nearly an hour without seeking ATC confirmation.
Organizational factors also contributed: inadequate pilot designation for the operation, insufficient training, and routine flight planning procedures lacking full crew participation.
In the air traffic control domain, several non-conformities were identified. The Brasília ACC controllers involved refused to participate in interviews, hindering precise identification of individual aspects. Among the findings:
- Incomplete flight clearance transmission by an assistant controller, deviating from procedure and adopting an informal pattern. This led the Legacy crew to believe they should maintain FL 370 all the way to Manaus.
- The ATCO of sectors 5 and 6 of Brasília ACC did not provide necessary information when coordinating and handing off the Legacy, indicating low situational awareness.
- The ATCO 1 of sectors 7, 8, and 9 of ACC BS did not contact the Legacy to change flight level or frequency, did not perceive the loss of Mode C, assumed FL 360, and failed to perform prescribed procedures for loss of transponder in RVSM airspace and for control position relief. The incomplete handoff contributed to diminished situational awareness, allowing the aircraft to exit frequency coverage and join the UZ6 airway at an incorrect level.
Aircraft and Damages
The Boeing 737-8EH was destroyed in the crash. The Embraer EMB-135BJ Legacy sustained damage to the left wingtip and left elevator but landed safely at SBCC.
Occupants
The Boeing 737 carried 6 crew and 148 passengers; all died. The Legacy carried 2 crew and 5 passengers; no injuries reported.
Probable Cause
The official probable cause cited human factors involving the Legacy crew and air traffic control. Specific active failures included lack of adequate flight planning, insufficient knowledge of the flight plan, non-execution of pre-departure briefing, unintentional transponder change, failure to prioritize attention, failure to perceive transponder non-transmission, delay in recognizing communication problems, and non-compliance with procedures. Low situational awareness was a relevant factor. Additionally, organizational and ATC non-conformities were identified, including incomplete clearances and coordination failures.