What happened
On January 20, 2024, a Robin DR40 and00-120, registration F-GUXI, was performing local circuit training at Saint-Cyr-l’École aerodrome. Due to operational restrictions in place that day, which prohibited touch-and-go landings and landings followed by a return to the holding point, the pilot intended to perform missed approaches for each circuit.
During the third approach on runway 11L, the aircraft passed over the adjacent A12 motorway at an extremely low altitude. While flying over the motorway, the pilot felt a light impact, which he believed was caused by striking an articulated lorry. The pilot immediately initiated a go-around. Following the incident, the aerodrome controller suggested a low pass over runway 11R to inspect the landing gear. Upon inspection after the flight, the pilot discovered rub marks and slight damage to the left wheel fairing.
The investigation
The investigation utilized Flarm flight data to reconstruct the aircraft's path. The data revealed that during the first two approaches, the aircraft flew over the motorway at heights of seven and nine meters, respectively. On the third approach, the aircraft's altitude dropped to just four metres above the motorway, a height consistent with the top of an articulated lorry.
The investigation also examined the pilot's recent flight experience and the aerodrome's operational environment. The pilot had logged 257 total hours but had very little recent activity, with only one 55-minute flight in the preceding three months. Additionally, the investigation noted that the use of displaced thresholds at Saint-Cyr-l’École reduces the available landing distance, and the pilot had focused more on the go-around procedure than on maintaining the correct approach slope and aiming point.
Findings
- The primary cause of the incident was the pilot's failure to maintain the correct approach slope and monitor the aiming point.
- The pilot's decision to perform missed approaches unaccompanied, despite a lack of recent experience and limited familiarity with runway 11L, contributed to the event.
- The aircraft's left main landing gear likely struck a lorry traveling north on the A12 motorway.
Safety action
- Aerodrome air traffic control has notified users of the incident, emphasizing the necessity of following published procedures and respecting displaced thresholds.
- The flying club intends to incorporate training on approach slope management and aiming point visualization into instructor-led recurrent training flights.