What happened
On January 4, 1998, an AS 355 F2 helicopter, registration PT-HNB, departed from Heliponto Marechiaro in Angra dos Reis, Rio de Janeiro, bound for Santos Dumont Airport. The aircraft was carrying the pilot and four passengers. During the flight, the crew encountered a heavy rain formation over the sea.
While flying at an altitude of approximately 300 feet, the aircraft entered the rain formation and was subjected to significant turbulence and wind gusts. During this period, the tail boom of the helicopter struck the water surface, causing a loss of control. The aircraft subsequently crashed into the sea and sank. While the pilot and three passengers successfully evacuated the cabin, one passenger remained trapped by their seatbelt and disappeared with the sinking aircraft. The wreckage was recovered approximately three months later.
The investigation
CENIPA's investigation focused on the mechanical condition of the aircraft, the pilot's qualifications, and the operational environment. Technical examinations of the engines, conducted by Rolls-Royce, revealed no mechanical abnormalities that could have contributed to the accident, noting only corrosion and marine growth resulting from the prolonged submersion in saltwater.
The investigation established that the pilot was qualified and experienced, but was operating with an expired Instrument Flight Rules (IFR) certificate. Furthermore, the investigation found that the aircraft was operating as an air taxi (TPX) despite being registered as private transport (TPP). The investigation also noted that the aircraft was not equipped with a sea survival kit or life jackets, and the passengers had not received safety briefings regarding emergency procedures or water landings.
Findings
- The primary cause of the accident was the pilot's decision to continue the flight into adverse weather conditions characterized by heavy rain and low visibility.
- Severe turbulence within the rain formation caused the tail boom to strike the water, leading to the loss of control.
- The pilot's decision-making was influenced by a desire to complete the mission before a scheduled maintenance period and a limited fuel reserve that discouraged significant deviations.
- Operational deficiencies included a lack of proper supervision by the operator, which failed to ensure necessary survival equipment was on board and that pilots maintained valid IFR certifications.
- The lack of passenger safety briefings and the absence of life jackets contributed to the fatality of the passenger who could not extricate themselves from the seatbelt.