What happened
On May 29, 2015, an AS-355N helicopter, registration PR-ADA, crashed in the state of Amazonas, Brazil, while performing a patient transport mission. The flight departed from Aldeia Pentiaquinho, destined for Tabatinga.
During the flight, approximately 19 nautical miles from Tabatinga, the aircraft collided with treetops between the municipalities of Atalaia do Norte and Benjamin Constant. The impact caused the aircraft to strike the ground, triggering a post-crash fire that destroyed much of the airframe. The pilot and four passengers were killed in the accident.
The investigation
CENIPA's investigation determined the accident was a controlled flight into terrain (CFIT). The investigation established that the pilot was flying under Visual Flight Rules (VFR) at night, despite the aircraft not being certified for Instrument Flight Rules (IFR) and the pilot not holding an IFR rating.
Investigators found that the pilot had requested an extension of the radio operating hours at Tabatinga to accommodate a late arrival. Meteorological data and radar images indicated the presence of significant rain clouds, including Towering Cumulus and Cumulonimbus, in the area. Local reports also confirmed thunderstorms and heavy rain. To maintain visual contact with the terrain in the deteriorating weather, the pilot flew at a very low altitude, which ultimately led to the collision with the forest canopy.
Findings
- The pilot's decision to fly at night, knowing the arrival would occur after sunset, significantly increased operational risks.
- Adverse meteorological conditions, specifically heavy rain and thunderstorms, reduced visibility and compromised the pilot's ability to maintain situational awareness.
- The pilot's attempt to maintain visual contact with the ground by flying at low altitude reduced the safety margin between the aircraft and obstacles.
- The pilot exhibited a complacent attitude toward regulations, specifically regarding night-time VFR operations outside of controlled airspace.
- Organizational failures within the operator were noted, specifically a lack of oversight regarding crew performance and adherence to operational standards.
- Inadequate flight planning occurred due to the short notice provided for the medical transport mission.