What happened
On 15 July 2019, a Schleicher ASK13 glider, registered F-CLAM, was conducting a local flight from the Montagne Noire aerodrome. After completing a flight with an instructor, the pilot took off in a towed flight and reached an altitude of approximately 1,000 m before releasing the tow rope. Following roughly 30 minutes of soaring, the pilot reached an altitude of about 300 m and joined the runway circuit.
While performing the base leg for runway 30, the pilot widened the traffic pattern to allow another glider to vacate the runway. During the final turn toward the runway, the aircraft descended below the required approach path. Fearing that attempting to reach the runway might result in an aerodynamic stall, the pilot decided to abort the approach and instead targeted the treetops located below the aerodrome level. Just before impact, the pilot executed a pull-up maneuver to reduce the energy of the collision. The aircraft sustained substantial damage during the landing in the trees.
The investigation
The BEA examined the flight data from the aircraft's FlyMaster F1 computer, meteorological reports, and statements from the pilot and an instructor. The investigation noted that the pilot had obtained his glider license only two months prior to the accident and had approximately 60 total flight hours. The investigation also reviewed the specific terrain and wind conditions at Montagne Noire, noting that runway 30 features a 10% downhill gradient and is susceptible to downdrafts when winds are from the northwest.
Findings
- The pilot did not sufficiently account for the effects of the northwesterly wind during the approach.
- The pilot lacked sufficient experience in managing the specific flight conditions and potential downdrafts associated with using runway 30 under northwesterly airflow.
- The decision to land in the trees was a deliberate choice to avoid a potential stall caused by being below the glide path.