What happened
On September 21, 2010, an HB 350B helicopter, registration PT-HLD, was performing a flight from a local village to a FUNASA post in Surucucu, Brazil. During the final approach to landing, the aircraft was operating near its maximum takeoff weight, having been loaded with passengers and cargo based on estimates rather than precise weighing.
As the pilot executed a flare approximately one meter above the ground, the aircraft entered an unintended 180-degree rotation to the right. During this maneuver, the helicopter descended, causing the right skid to strike the ground. The impact caused the aircraft to capsize onto its right side, resulting in severe damage to the airframe, engine, and rotors. The pilot and four passengers sustained minor injuries.
The investigation
CENIPA's investigation focused on the pilot's decision-making and the aircraft's technical status. Investigators found that while the pilot was highly experienced in the region, he lacked specific type training for the HB 350B model, having been trained on the HB 355 instead.
Technical inspections revealed that the aircraft's maintenance logs were out of date, with some entries recorded after the accident occurred. Furthermore, the investigation identified issues within the hydraulic system, specifically that two nitrogen bottles in the accumulators were at zero pressure and the system was contaminated. The investigation also noted that the aircraft was operating with a tailwind and that the pilot had failed to use the manufacturer's checklist during the loading process.
Findings
- Overconfidence and poor judgment: The pilot's extensive experience in the Amazon region contributed to a sense of invulnerability, leading to a failure to properly account for wind direction, wind speed, and the aircraft's actual weight.
- Inadequate flight planning: The pilot opted to carry 60% fuel capacity when 40% would have sufficed, unnecessarily increasing the aircraft's weight near its maximum limit.
- Improper command application: The pilot performed a flare during a tailwind approach, which, combined with the high weight, contributed to the loss of control.
- Lack of specific training: The pilot had not received the required initial training for the HB 350B model for this specific operation.
- Inadequate management supervision: The operator failed to ensure the pilot used proper checklists and failed to verify the precise weight of passengers and cargo.