Incident
Approximately 42 minutes after departing from Cuiabá Airport, the aircraft was cruising at 10,000 feet. The captain obtained permission to descend to 8,000 feet to avoid a low-pressure area with thunderstorm activity and heavy rainfall. Seconds later, the twin-engine aircraft went out of control, dove into the ground, and crashed in an open field in Tangará da Serra. All four passengers and both pilots were killed. The aircraft was destroyed on impact.
Investigation
The official investigation determined that the loss of control was probably caused by spatial disorientation of the pilot in command, who was unable to establish his correct position due to poor visibility from heavy rainfall. Additionally, the investigation identified several factors that may have contributed to the captain's loss of control: disease, visual and hearing impairment, arteriosclerosis, obesity, and heart problems.
Probable Cause
The probable cause was poor flight preparation on the part of the flying crew, who did not take into consideration the probability of en route deterioration of weather conditions.