What happened
On Sunday, 15 June 2025, a Mudry Cap 232 registered F-HKAP departed Chavenay - Villepreux aerodrome at 13:56 local time. The aircraft was on a ferry flight to Rochefort - Charente-Maritime for an aerobatics course. Shortly after takeoff, as the pilot exited the Radio Mandatory Zone (RMZ), he noticed the canopy was slightly open. Attempting to close it, the mechanism failed, causing the canopy to fully open and then separate from the fuselage.
The sudden loss of the canopy exposed the pilot to high relative wind, tearing part of his headset away and making it difficult to maintain visual references or read instruments. The pilot lost radio contact with air traffic control (ATC) and initiated a return to the departure aerodrome. ATC observed the aircraft on radar but could not establish communication. The pilot performed a low pass near the control tower to demonstrate the missing canopy, then attempted a final approach to runway 28. Due to impaired perception of altitude and difficulty controlling the aircraft without the canopy, the plane struck the ground approximately 350 meters from the start of the runway. The pilot was injured, and the aircraft was destroyed.
The investigation
The BEA examined wreckage, pilot statements, radar data, and meteorological records. The weather was calm with good visibility. The investigation focused on the canopy locking system, which allows a "slightly open" position for ventilation during taxiing. The pilot admitted to leaving the canopy in this position before takeoff to circulate air in the cockpit. When he attempted to transition from the slightly open to the closed position in flight, the locking rod likely disengaged incorrectly, leading to full opening and separation.
The BEA noted that the Cap 232 flight manual requires a pre-takeoff check of the canopy lock but does not provide a specific abnormal procedure for an unlocked canopy in flight. The pilot’s difficulty in maintaining control was attributed to the aerodynamic effects of the missing canopy and the physical strain of fighting the wind, which also prevented him from displaying the emergency transponder code 7700.
Findings
The primary causal factor was the separation of the canopy during an attempt to close it in flight. Contributing factors included:
- The pilot’s decision to leave the canopy in the slightly open position before takeoff.
- The lack of a specific emergency procedure for this scenario in the aircraft manual.
- Impaired visual references and control difficulties due to wind exposure, which led to a low-altitude approach and collision with the ground.