What happened
On June 5, 1993, at approximately 22:50 Z, a Beechcraft BE-90, registration PP-FPP, operated by the Brazilian Federal Police, crashed into terrain in the Chapada dos Guimarães region, approximately 34 nautical miles north of Cuiabá, Mato Grosso.
The flight departed from Alta Floresta bound for Cuiabá. During the descent, the crew requested and received authorization to descend to FL 060. While the aircraft was 67 NM from Cuiabá, the pilot reported the start of the descent. However, a significant delay was noted in the aircraft's progress; while the flight time for 10 NM should have been approximately 3 minutes and 15 seconds, it took the aircraft 23 minutes and 30 seconds to travel from 67 NM to 57 NM DME. During this interval, the crew failed to report their altitude. The aircraft eventually struck elevated terrain at approximately 1,960 feet MSL, 4,000 feet below the authorized altitude.
The investigation
CENIPA's investigation focused on the flight's progress and the crew's training status. Investigators found that the aircraft's engines and propellers were producing power and traction consistent with cruise flight at the time of impact. There were no signs of mechanical failure, fuel contamination, or in-flight fire.
The investigation revealed that the co-pilot, who was acting as the pilot in command at the time of the accident, had very limited experience in the BE-90, with only 15:30 hours of instruction over the previous eight months. The investigation also noted that the organization lacked a formal, standardized training program, leading to improvised training maneuvers during the flight. The presence of wreckage patterns suggested a high-speed impact consistent with a stall recovery attempt or spatial disorientation.
Findings
- Inadequate training: The co-pilot lacked sufficient recent experience in the aircraft type, and the organization lacked a structured training and supervision program.
- Improvised maneuvers: The significant delay in the descent suggests the crew was likely performing unapproved flight maneuvers or basic instrument training.
- Loss of situational awareness: The crew's failure to maintain the authorized altitude and the pilot's failure to report altitude during radio contact indicate a high level of distraction or fixation on training tasks.
- Spatial disorientation: The night operation over unpopulated, featureless terrain likely contributed to spatial disorientation, making it difficult to recover from an abnormal attitude.
- Lack of safety equipment: The aircraft was not equipped with an Emergency Locator Transmitter (ELT) and lacked a jungle survival kit, despite flying over forested areas.