What happened
On March 15, 2003, at 16:48 UTC, an air traffic incident occurred at Geneva Airport involving an Alitalia ATR72 (AZA593) and a private Mooney 20M (F-GLHK). The Mooney 20M was operating a VFR flight from Muret-Lherm to Geneva. Upon arrival, the pilot of F-GLHK requested landing on the paved runway rather than the designated grass runway due to the aircraft's retractable landing gear.
While the tower controller was managing a high volume of traffic, the Alitalia flight was cleared for an immediate takeoff on runway 05. Simultaneously, the pilot of the Mooney 20M began a left turn to join the traffic pattern. As the ATR72 climbed through 2500 feet, the aircraft's TCAS issued a Resolution Advisory (RA) commanding a descent. The Alitalia crew immediately responded by leveling off and reducing power to avoid a conflict. The minimum separation between the two aircraft was approximately 0.5 NM laterally and 500 feet vertically.
The investigation
The investigation examined the flight paths, radio communications, and air traffic control management. It was established that the tower controller in charge of the communications was a trainee under the supervision of a coach. The investigation found that the trainee controller had authorized the Alitalia flight to take off while the Mooney 20M was still maneuvering in the vicinity.
Radar records and flight path analysis confirmed that the Mooney 20M was not following the specific arrival instructions provided by the controller. The controller had instructed the pilot to report at a specific waypoint and join the pattern after passing another, but the pilot's trajectory deviated significantly from the assigned route. Furthermore, the supervising coach admitted to allowing the trainee to integrate the VFR aircraft into the IFR arrival sequence for instructional purposes despite the heavy traffic load, and noted that visual contact with the Mooney 20M had been lost due to tower obstructions.