What happened
On December 29, 2011, an AS-350B2 helicopter, registration PR-JLL, was performing a flight from Fábrica Fortaleza to Fazenda Gentilândia. During the mission, the pilot planned an intermediate stop in a non-aerodrome area near Beach Park, in Aquiraz, Ceará, to pick up an additional passenger.
The landing site consisted of a 30x30 meter plateau of dry clay, which was slightly elevated above the surrounding terrain. As the pilot executed the final approach and performed a flare to reduce airspeed, the tail rotor made contact with the ground. This impact caused a severe vibration in the flight controls and a subsequent loss of aircraft control. To mitigate the impact, the pilot reduced engine power to the "stop" position, resulting in an autorotative landing. The aircraft spun around its vertical axis upon touchdown, causing substantial damage to the tail boom, tail rotor, vertical fin, and landing gear. All four occupants (the pilot and three passengers) escaped the accident without injury.
The investigation
CENIPA's investigation was significantly hindered because the occurrence was not reported to the authorities until approximately six months after the event. This delay prevented the use of advanced investigative techniques and physical testing.
The investigation examined the pilot's experience, the aircraft's maintenance history, and the environmental conditions at the landing site. The aircraft's maintenance records were up to date, and the pilot was fully qualified with a valid commercial license and medical certificate. The investigation focused on the pilot's decision-making regarding the landing maneuver and the visual challenges presented by the terrain.