Sequence of Events
On 6 March 2013, a Piper PA28-161 registered F-GHPN departed from Persan Beaumont airfield at 20:03 local time for a night VFR navigation to Pontoise, approximately 12 nautical miles away. Seven minutes after departure, the pilot announced on the self-information frequency that he had canceled the flight due to a GPS problem and was returning for touch-and-goes on runway 10. At 20:12, he announced a go-around, and at 20:16, he reported being on final for runway 10. The aircraft was subsequently found in a field 585 meters before the displaced threshold of runway 10.
Collision and Wreckage
The aircraft struck a small isolated grove with its right wing at a distance of about 660 meters from the displaced threshold. Impact occurred at a height of approximately 5 meters on a slightly descending trajectory with nearly zero bank. The tree struck was outside the runway 10 approach clearance surface. Examination of the wreckage revealed no pre-impact malfunctions: the engine was delivering power, and the flaps were not retracted (exact position could not be determined due to damage). The altimeter was set to 1000 hPa (the local QNH) and indicated field elevation. Switches were found in various positions: transponder off, GPS off, landing light off, navigation lights off, and anticollision lights on. The pilot's seatbelt buckle was found open and in good condition; the torso restraint was stowed. The canopy was destroyed, with no evidence of opaqueness on fragments.
Pilot Information
The pilot, aged 72, held a private pilot license issued in 1999, with approximately 990 total flight hours, including 855 as pilot-in-command. He obtained a night rating in 2008 and had about 34 hours of night flying experience, including a 43-minute circuit on a PA28 at Persan eleven days prior. His last night VFR instruction flight was in September 2008. He possessed a valid Class 2 medical certificate issued in October 2012, which required corrective lenses. Autopsy revealed dilation of heart cavities—a condition that may cause cardiac rhythm disorders and fatigue—as well as a lens opacity suggestive of possible cataract, which can impair vision in low light conditions.
Additional Information
Witnesses, including an instructor and student conducting circuits, observed the aircraft was very low on both finals but did not communicate with the pilot to avoid disturbing him. Weather conditions were good and calm. Club members noted the pilot had appeared particularly tired in recent days. The flight plan for Pontoise was activated by phone but not canceled; no ATC contact was made, and the accident flight was not recorded by secondary radar. Runway 10 is paved, 830 m by 20 m, with a landing distance available of 750 m. It is equipped with low- or high-intensity edge, threshold, and end lights; the lighting was operating in low intensity at the time. No precision approach path indicator (PAPI) is installed on runway 10.
Conclusion
Investigation findings indicate that the pilot's operational performance, medical factors, and witness statements point to a state of fatigue. A possible visual discomfort from lens opacity may have increased difficulties in acquiring visual cues and controlling the trajectory on final. The pilot descended below the nominal glide path, did not realize his proximity to vegetation, and executed no evasive maneuver. The low height and trajectory at impact are characteristic of a visual illusion known as 'black hole approach' (Kraft illusion). Fatigue and degraded visual performance likely contributed to this illusion.