What happened
On February 1, 2016, a Socata TBM700N, registration PP-LIG, departed from Hercílio Luz Airport (SBFL) in Florianópolis, Brazil, bound for Ji-Paraná, Rondônia. The flight was a private transport mission carrying a pilot and one passenger.
Shortly after takeoff, while climbing through approximately 3,000 feet, the aircraft began a right-hand turn. Radar data indicated that the aircraft's flight path became unstable, showing variations in course and speed that suggested manual control without the use of autopilot. At 3,600 feet, the aircraft initiated a steep right turn, completing a full 360-degree circle before disappearing from radar contact. The aircraft subsequently entered a descending spiral and impacted the sea. Debris was found on the surface the same day, and the wreckage and the two occupants were recovered 14 days later. Both the pilot and the passenger died in the impact.
The investigation
CENIPA's investigation focused on the flight dynamics and the environmental conditions during the departure. The investigation established that the aircraft was operating under Instrument Flight Rules (IFR) due to overcast conditions, with cloud bases between 1,700 and 8,000 feet.
Investigators examined the pilot's experience, noting that while the pilot held a valid Commercial Pilot license and was qualified for the aircraft type, he had limited experience conducting IFR operations in actual instrument meteorological conditions (IMC). The investigation also looked into the possibility of visual illusions caused by the night flight over the ocean, where the loss of terrestrial light references can lead to spatial disorientation. Furthermore, the investigation considered whether language barriers regarding English-language cockpit resources might have impacted the pilot's ability to manage the aircraft's systems effectively.
Findings
- The primary hypothesis is that the pilot experienced spatial disorientation during the instrument departure procedure, which led to an unrecoverable flight state.
- The flight took place at night over the ocean, creating conditions highly susceptible to visual illusions and spatial disorientation.
- The pilot's lack of extensive experience in IMC environments may have contributed to the inability to recover from the developing spiral.
- There was evidence of manual flight without autopilot assistance, which may have been complicated by a lack of familiarity with the aircraft's English-language systems and interface.
- The aircraft was operating within weight and balance limits, and the engine was producing high power at the moment of impact.