What happened
On April 8, 2023, at approximately 16:30, a Jodel DR250-160 registered HB-KFS was performing a takeoff from runway 05 at the Saulieu-Liernais aerodrome in France. The flight was part of a cross-country trip involving multiple aircraft and passengers. Prior to the accident, another aircraft, a Cessna registered HB-COE, performed a low pass on the left side of the runway while the HB-KFS was beginning its takeoff roll.
As the HB-KFS accelerated and the tailwheel left the ground, the aircraft began to deviate toward the left side of the runway. Despite the pilot applying right rudder input, the deviation continued, bringing the aircraft toward the edge of the runway. During this maneuver, the left wing of the HB-PTFS struck a pedestrian who was standing on the grass near the runway edge while filming the aircraft. The aircraft continued to veer left, exited the runway, and overran a ditch, eventually coming to rest on its back. The accident resulted in one pedestrian seriously injured and three occupants of the aircraft injured, while the aircraft was destroyed.
The investigation
The BEA examined the wreckage of the HB-KFS, focusing on the rudder controls and landing gear. The investigation found no mechanical failures; the rudder control cables were intact, and the tailwheel and landing gear were in good working condition. Video footage from the pedestrian's mobile phone confirmed that the aircraft was relatively centered upon lining up but drifted significantly to the left during the takeoff run. The footage also showed the rudder was deflected to the right during the excursion.
The investigation also reviewed the circumstances surrounding the flight, including the presence of alcohol. A blood sample taken from the pilot of the HB-KFS approximately three hours after the accident showed an ethanol level of 0.32 g/L. Additionally, the pilot of the HB-COE admitted to consuming alcohol during a lunch held earlier that day.
Findings
- The primary cause of the deviation was a combination of the aircraft's natural takeoff characteristics (spiraling slipstream and torque), the windvane effect from a crosswind, and the aerodynamic disturbance caused by the wake turbulence from the HB-COE low pass.
- Alcohol consumption likely contributed to the accident by impairing the pilot's judgment and reaction time, potentially preventing a decision to abort the takeoff and hindering the ability to correct the flight path.
- The consumption of alcohol by the various parties involved likely led to a poor assessment of risk, specifically regarding the pedestrian's proximity to the runway and the decision to perform a low pass in close proximity to an active takeoff.