What happened
On December 30, 2011, a Robinson R44 II helicopter, registration PR-FPE, was performing a visual flight approach to a public square in Iguaba Grande, Rio de Janeiro. The flight, operated by EGEMP Gestão Patrimonial Ltda., was intended to facilitate a landing at a local festival.
During the final approach, the aircraft entered an abnormal attitude, characterized by a violent yaw to the right. The pilot was unable to regain control of the aircraft, leading to a collision with an inflatable toy structure located within the event area. The impact caused substantial damage to the helicopter, including damage to the main rotor blades, main rotor shaft, transmission, upper fuselage structure, and tail boom, as well as a broken windshield.
While the pilot remained uninjured, the three passengers sustained light injuries. A child present in the square suffered serious injuries as a result of the accident.
The investigation
CENIPA's investigation focused on the aerodynamic conditions during the approach and the legality of the landing site. Investigators determined that the pilot performed the approach with a crosswind/tailwind component. The analysis established that the aircraft experienced Loss of Tail Rotor Effectiveness (LTE), a critical aerodynamic phenomenon occurring at low speeds where the tail rotor fails to produce sufficient thrust to counteract yaw, often triggered by specific wind angles.
Furthermore, the investigation noted that the landing site was not a certified helipad and lacked the necessary dimensions for a safe operation. The investigation also found that the operation lacked the required prior authorization from the National Civil Aviation Agency (ANATEL/ANAC) for landing at a scheduled public event.
Findings
- The primary cause of the loss of control was Loss of Tail Rotor Effectiveness (LTE).
- The pilot's control inputs were insufficient to counteract the sudden yaw.
- The landing area was not a recognized or approved landing site and did not meet the physical requirements of a standard helipad.
- The pilot did not utilize available meteorological information during the flight.
- The operation was conducted without the necessary prior authorization from the competent aeronautical authority for a programmed event.