Incident Overview
On October 16, 1998, at 14:06 local time (UTC+2), a privately owned Robin DR 400-140B with registration HB-KDB was involved in an accident at the Ecuvillens aerodrome in Switzerland. The aircraft was operated by a student pilot holding a valid license for single-engine airplanes. The flight originated from Sion and followed a planned route to Ecuvillens. During the final approach, the pilot executed a stabilized landing on runway 28.
Sequence of Events
Witnesses described the touchdown as a precise three-point landing with wings level, though at an apparently high speed. Immediately after contact with the ground, the aircraft began to turn slowly to the right without apparent corrective action from the pilot. The plane left the paved runway, crossed the grass safety area, and entered a freshly plowed field. As the trajectory curved left, the nose gear dug into the soil, causing the right wing to strike the ground. The aircraft subsequently rolled over, resting on its nose wheel and propeller.
Investigation Findings
The investigation determined that the pilot was in good health and the aircraft was airworthy, with weight and balance within limits. Technical inspections of the braking system revealed no defects or maintenance issues. Skid marks indicated that the left main wheel skidded due to centrifugal force generated by the right turn, confirming that the wheel rotation was not obstructed.
Probable Cause Analysis
The accident was attributed to a loss of control during the deceleration phase after landing. The probable cause was identified as an erroneous action on the rudder pedals. The pilot later acknowledged a tendency to press the right pedal when the aircraft deviated to the right, particularly under stress or divided attention. This realization led the student to discontinue their flight training.