What happened
On January 21, 2025, a Pilatus PC-6/B2-H4, registration HB-FDU, was conducting a cargo flight from Cayenne-Félix Éboué to Maripasoula aerodrome in French Guiana. The aircraft was transporting food supplies under a dry lease arrangement.
During the approach to runway 07, the pilot performed a 180-degree turn to align with the runway axis. As the aircraft transitioned to short final, the pilot extended the flaps to near-maximum deployment. During this phase, the aircraft's pitch attitude increased significantly while the indicated airspeed dropped. The pilot attempted to correct the pitch and increase power, but the aircraft's speed continued to decay until it reached approximately 46 knots, falling below the stall speed. The pilot lost control, and the aircraft collided with the ground approximately 160 meters from the runway threshold, coming to rest on the left side of the runway. The pilot sustained serious injuries, and the aircraft was substantially damaged.
The investigation
The BEA examined the wreckage, flight data, and maintenance records. Investigators found the aircraft was heavily loaded with approximately 1,069 kg of cargo. While a weight and balance sheet provided by the pilot indicated the aircraft was within limits, manufacturer analysis suggested the aircraft was operating near its maximum landing weight and at an aft center of gravity limit.
Technical examination of the flight controls showed they were functional, and the engine was producing moderate to high power at the moment of impact. The investigation also reviewed the engine's idle control settings and the impact of high outside air temperatures (approximately 30°C) on flight performance.
Findings
Several factors contributed to the loss of control:
- The aircraft was operating with an aft center of gravity and near its maximum landing weight.
- The deployment of flaps to a near-maximum setting created significant nose-up torque and increased drag.
- The high weight and increased drag likely caused a rapid deceleration that the pilot could not effectively counter with power adjustments.
- High pilot workload during the final approach, caused by the rapid configuration of the aircraft, likely led to insufficient monitoring of the airspeed.