What happened
On March 26, 2005, a Cessna 172 R Skyhawk, registered F-HAJA, was conducting a VFR flight from Amiens to Fayence, with a scheduled stop in Clermont Ferrand. The aircraft was carrying a pilot and two passengers. After refueling in Clermont Ferrand, the flight continued toward its destination.
During the second leg of the journey, the aircraft''s radar track showed it passing near Avignon and moving toward the coast. At 16:55 UTC, the pilot established contact with Nice Information, stating they were descending from 3,700 ft to 2,000 ft. However, radar data and transponder records indicated the aircraft was actually much lower, at approximately 2,700 ft. Shortly after, the aircraft disappeared from radar. The wreckage was discovered the following morning near the summit of the Colle Dure mountain.
The investigation
The investigation focused on the flight conditions and the pilot's navigation. The aircraft was equipped with a GPS coupled to an autopilot, which appeared to have maintained a steady course despite significant crosswinds. Investigators found that the pilot was flying under Visual Flight Rules (VFR) but was likely operating in Instrument Meteorological Conditions (IMC) due to heavy cloud cover.
Analysis of the transponder data revealed a significant discrepancy between the pilot's reported altitude and the actual altitude. While the pilot announced a descent to 2,000 ft while believing they were at 3,700 ft, the transponder showed the aircraft was already at 2,700 ft. The investigation also noted that the pilot had not consulted recent meteorological updates during the stop in Clermont Ferrand.
Findings
- The collision with the terrain occurred at an altitude of 1,650 ft during a descent.
- The three fatalities occurred because the aircraft struck the mountain while flying in clouds that obscured the terrain.
- The pilot likely suffered from an altimeter reading error, leading them to believe they were at a safe altitude when they were actually much lower.
- The decision to continue the flight despite deteriorating weather conditions contributed to the accident.
- The use of the GPS-coupled autopilot may have provided a false sense of security regarding navigation and altitude.