What happened
On June 7, 2014, at approximately 01:27 local time, an AS 350 BA helicopter, registration PT-YJJ, crashed near Aruanã, Goiás, Brazil. The aircraft was performing a nighttime departure from a camp located on an island in the Aragua and Araguaia River.
The flight was intended to transport the pilot and four passengers to a residence approximately 14 km away. The takeoff sequence began with a vertical lift, followed by a right tail rotation. During the transition to horizontal flight, the aircraft struck the ground approximately 430 meters from the departure point. The impact caused substantial damage to the airframe and resulted in five fatalities (the pilot and four passengers).
The investigation
CENIPA's investigation focused on the circumstances surrounding the night departure from an uncertified location. Investigators examined the aircraft's maintenance records, noting that while the airworthiness certificate was valid, several scheduled inspections (including 10h, 25h, and 30h intervals) had not been recorded since February 2014.
The investigation also reviewed the pilot's qualifications, noting that while the pilot held a valid commercial license, they did not possess an instrument rating (IFRH), and the aircraft was not certified for IFR operations. Environmental factors were heavily scrutinized, specifically the lack of ground lighting and visual references at the departure site, which contributed to a high risk of spatial disorientation.
Findings
- Spatial Disorientation: The lack of ground lighting, the position of the moon behind the aircraft, and the absence of a visible horizon likely led to visual or vestibular illusions. It is hypothesized that a somatogravic illusion may have caused the pilot to incorrectly perceive the aircraft's pitch, leading to an inappropriate control input that drove the aircraft into the terrain.
- Inadequate Decision Making: The pilot chose to conduct a nighttime VFR operation from an uncertified, unlit location using an aircraft not equipped for instrument flight, without the necessary instrument rating.
- Regulatory Non-compliance: The operation violated established flight rules (ICA 100-4) regarding night VFR procedures.
- Operational Environment: The absence of external visual references and the lack of ground lighting at the riverside camp significantly increased the risk of the accident.
Safety action
CENIPA issued the following recommendations to the National Civil Aviation Agency (ANAC):
- Redefine the parameters within RBHA 91.327 regarding helicopter operations at uncertified or unregistered locations to ensure the safety of occupants and third parties.
- Redefine the minimum training requirements for civil helicopter pilots to ensure they possess comprehensive knowledge of the risks associated with spatial disorientation.