What happened
On the afternoon of July 29, 2022, a Robin DR400-100, registration F-GKQE, was performing a left-hand runway circuit at Biarritz - Pays Basque airport. The flight was an instructional session involving an instructor and a student pilot. As the aircraft was on final approach to runway 27, at an altitude of approximately 450 feet, the crew identified a group of four to five large birds, potentially birds of prey, near the flight path.
During the approach, a bird changed course and collided with the propeller before striking the left-hand wing. Following the impact, the instructor determined that the aircraft remained controllable. The instructor notified air traffic control of the strike and declared the intention to perform a full-stop landing rather than a touch-and-go. The student pilot, who was maintaining control of the aircraft, completed the landing without further incident.
The investigation
Investigators examined the structural integrity of the Robin DR400-100 following the event. The inspection revealed that while the propeller blade, the elevator, and the left-hand main landing gear fairing showed marks from the impact, they sustained no visible structural damage. However, the leading edge of the left-hand wing suffered significant damage; the plywood and a wing rib were destroyed, resulting in a dent and tear approximately 10 cm wide and 20 cm deep.
The investigation also reviewed the environmental conditions at Biarritz - Pays Basque airport. The airport features extensive grassland that attracts various bird species. While management implements several mitigation strategies, such as night mowing and bird-scaring techniques, the investigation noted that these measures are ineffective against large-scale bird migrations occurring between March and November.
Findings
- The primary cause of the incident was a bird strike involving a large bird, possibly a vulture, during the final approach.
- The low airspeed of the aircraft during the final approach and the limited time remaining before touchdown likely mitigated the extent of the structural damage.
- The instructor's decision to allow the student pilot to continue the landing was influenced by the fact that the aircraft's controllability was not compromised.
- The structural vulnerability of the aircraft's wood and canvas construction contributes to the severity of damage during high-energy collisions.