What happened
On January 19, 1997, a Robin DR 400-180, registration F-BXVC, departed from Pierrelatte for a short local flight intended to visit Pont St Esprit and return. During the flight, while attempting to locate a passenger's house by performing a wide right-hand turn east of Pont St Eslin, the pilot entered a cloud layer and lost all external visual references.
Aware of the terrain and obstacles within the valley, the pilot elected not to descend immediately, instead turning north to attempt to regain visual contact with the ground. However, the aircraft remained in instrument meteorological conditions (IMC) for approximately three to four minutes. Unable to recover visual references, the pilot decided to perform an emergency landing while still flying "blind." The crew prepared the aircraft for impact and executed a descent on a shallow glide path at reduced speed. The ground became visible only moments before the aircraft struck trees in a wooded area.
The investigation
The investigation established that the pilot had relied on weather information obtained from other pilots returning from recent flights. This information suggested visibility of approximately 5 km and a ceiling of 1500 feet, conditions that appeared to be confirmed during the initial minutes of the flight.
However, meteorological analysis revealed more complex conditions in the area. An occluded front was moving through the region, bringing overcast skies and continuous light rain to the Rhône valley. While visibility was reported between 5 and 6 km, the presence of stratocumulus clouds at lower altitudes (between 1000 and 1300 feet) and significant turbulence contributed to the difficulty of maintaining visual flight rules.
Findings
- The primary cause of the accident was the loss of external visual references during a maneuver.
- The pilot attempted to maintain altitude to avoid valley obstacles but remained trapped in clouds for several minutes.
- The aircraft sustained significant damage, resulting in the destruction of the Robin DR 400-180.
- The accident resulted in injured occupants, including the pilot and three passengers.