What happened
On 11 December 2021, at approximately 16:30, a ROBIN DR400 - 160, registered F-BUSE, was performing a local flight at Lyon-Bron airport. The aircraft was following a Piper PA28, registered F-GCQE, which was conducting a local instruction flight.
As the pilot of F-BUSE reached the end of the downwind leg for runway 34, the air traffic controller informed him that he was second in sequence behind the PA28. The controller instructed the pilot of F-BUSE to call back once on final approach. During the transition from the downwind leg to the base leg, the pilot of F-BUSE initiated a right turn with a bank angle of approximately 20-30 degrees and began a descent.
At this time, the aircraft was on a converging path with the PA28. The air traffic controller observed the proximity and queried the pilot of F-BUSE regarding whether he had visual contact with the preceding aircraft. When the pilot reported that he did not have sight of the PA28, the controller instructed F-BUSE to perform a go-around. The instructor on board the PA28 reported that the ROBIN DR400 had missed their aircraft by approximately 10 m. The pilot of F-BUSE executed the go-around and subsequently landed after completing an airport circuit.
The investigation
The investigation examined the flight paths, radio communications, and the responsibilities of both the flight crews and air traffic control. The investigation established that the airport operates in Class D airspace, where air traffic controllers provide traffic information and avoidance advice upon request, but do not provide separation between VFR flights. Under these regulations, VFR pilots are responsible for maintaining separation through the "see-and-avoid" principle.
Findings
- The pilot of F-BUSE initiated the turn toward the final approach without visually searching for the preceding aircraft.
- The pilot of F-BUSE demonstrated a lack of understanding regarding the specific services provided by controllers to VFR aircraft in Class D airspace, mistakenly believing the controller was responsible for ensuring separation.
- The potential collision was avoided due to the controller's effective visual monitoring of the circuit and the use of calm, firm, and appropriate phraseology during the go-around instruction, which prevented unnecessary pilot stress.