What happened
On July 2, 2011, a Robin DR400-160, registration F-GKIM, was preparing for a local flight around the Gulf of Morbihan from Quiberon Aerodrome. The pilot, who was accompanied by three passengers, had decided to perform this flight following a change in weather conditions. After refueling the aircraft to its maximum capacity, the pilot lined up on runway 11.
During the takeoff roll, the pilot applied full power. Aware that the aircraft was near its maximum takeoff weight, the pilot chose to rotate at 110 km/h, which was higher than the 100 km/h speed specified in the flight manual. Shortly after rotation, the stall warning alarm activated. The pilot momentarily relaxed pressure on the controls to regain a sense of the aircraft's behavior and shifted his attention toward the external environment rather than monitoring airspeed.
As the aircraft flew near the shoreline at the end of the runway, the pilot applied further back-pressure on the controls, triggering the stall warning a second time. The aircraft entered an asymmetric stall to the right at a low altitude. The pilot was unable to recover control, and the aircraft impacted the ground. Before impact, the pilot had moved the throttle to idle and attempted to secure the aircraft by turning the magnetos off and closing the mixture.
The investigation
Investigators examined the aircraft's weight and balance configuration and the pilot's flight preparation. The investigation established that the aircraft was at its maximum takeoff weight (within a 10 kg margin) and that the center of gravity was near the aft limit (3-30.5% of the 33% limit).
Air Traffic Services (AFIS) personnel observed the aircraft maintaining a high pitch attitude early in the climb, followed by a level attitude at low altitude, before the pitch increased significantly again leading into the stall. The investigation also noted that while the pilot had received theoretical training on weight and balance, he had not specifically evaluated the center of gravity for this flight and had not fully accounted for how the high mass would affect flight performance.
Findings
- The primary cause of the accident was the insufficient consideration of weight and balance parameters during flight preparation.
- The pilot was surprised by the impact of the aircraft's high mass on takeoff performance and handling.
- The pilot's attention shifted from airspeed monitoring to environmental awareness due to the proximity of the sea at the end of the runway.
- The pilot's decision to apply back-pressure on the controls while at a low altitude and high weight led to the final stall.
- There was a lack of practical understanding regarding how maximum weight affects the power required for flight and how aft center of gravity affects stability and maneuverability.