What happened
On the morning of September 29, 1968, a Piper J3C, registration HB-ODG, departed from Porrentruy for a private local flight. The pilot was accompanied by his brother. The flight was intended to include a low-altitude overflight of the pilot's family home. During maneuvers near the farmstead of Les Côtes, the aircraft descended rapidly and struck the ground near a path leading to the Ordons ridge. The impact, which occurred at an angle of at least 45 degrees, destroyed the aircraft and resulted in two fatalities.
The investigation
Investigators examined the wreckage and found no evidence of mechanical failure. The engine, propeller, and flight controls were all in functional condition prior to the impact. The investigation also reviewed the pilot's flight logs, which revealed that while he held a valid private pilot license, his training was highly irregular. After completing his initial training in late 1967, he had not performed any significant flight activity for over ten months prior to the accident.
Additionally, investigators analyzed a Super 8mm film found at the scene. The footage, captured from the passenger seat, documented the flight path from Porrentruy through various landmarks, ending with the aircraft performing turns over the family farm. The investigation also considered the possibility of passenger interference, as the passenger had been filming during the flight.
Findings
- The primary cause of the accident was a loss of control at an altitude too low to allow for recovery.
- The pilot was considered inexperienced and poorly trained due to a long period of flight inactivity.
- The aircraft likely entered a stall, potentially caused by insufficient monitoring of airspeed or an accidental movement of the flight controls by the passenger while filming.
- Light turbulence or a sudden gust of wind may have contributed to the loss of lift during the maneuver.