What happened
On November 8, 2008, at 15:13 UTC, a mid-air collision occurred near Arthaz-Pont-Notre-Dame, France, involving two aircraft operated by the Club Aéronautique d’Annemasse. The first aircraft, a Piper PA 28 (registration F-GOMP), was performing its third right-hand circuit for runway 12 at Annemasse aerodrome. Simultaneously, a Robin DR 400-120 (registration F-GTZK) was returning from a local flight and was integrating directly into the downwind leg of the circuit at a slightly lower altitude than the circuit pattern.
As the Piper PA 28 was executing a right turn to join the downwind leg, it collided with the Robin DR 400-120. The impact caused the structural disintegration of the Robin DR 400-120, leading to the death of its pilot. The Piper PA 28 suffered significant damage, including the loss of its wings and partial engine detachment, but the pilot managed to perform an emergency landing in a field, where he sustained serious injuries.
The investigation
The BEA investigation examined the flight trajectories using radar data from La Dole, Switzerland. The radar tracks confirmed that the Piper PA 28 was turning right toward the downwind leg while the Robin DR 400-120 was flying a straight path parallel to the A40 motorway, climbing slightly as it integrated into the downwind leg.
Investigators analyzed the cockpit communications and local aerodrome procedures. While the pilot of the Piper PA 28 had been regularly broadcasting his position on the self-information frequency, the pilot of the Robin DR 400-120 had not announced his intention to integrate into the circuit. The investigation also looked into the specific layout of the runway 12 circuit, which lacks a crosswind leg, and the local practice of skipping the overhead pass when joining the circuit.
Findings
- The primary cause of the accident was a failure of mutual visual detection between the two pilots.
- The pilot of the Robin DR 400-120 did not transmit any radio messages regarding his intention to join the circuit.
- The local practice at the aero club involved integrating directly into the circuit without performing an overhead pass, which reduced the opportunity to identify other traffic.
- The specific design of the runway 12 circuit at Annemasse, which requires a long turn and lacks a crosswind leg, created a blind spot where the Piper PA 28 could not see the Robin DR 400-120 due to its low-wing configuration, and vice versa.