What happened
On December 4, 2015, a Robin DR400-140, registration F-GAHG, departed Chavenay for Colmar Houssen under Visual Flight Rules (VFR). The flight, operated by a local flying club, included the pilot and one passenger.
During the flight, the pilot maintained contact with various flight information services, including Saint-Dizier and Strasbourg. While cruising at FL75, the pilot inquired about the weather at the destination. Information received indicated overcast skies and fragmented clouds at various altitudes. Seeking better conditions, the pilot adjusted the course toward the southeast. However, shortly after leaving the Strasbourg frequency and contacting the Basel flight information service, the pilot reported entering Instrument Meteorological Conditions (IMC). Moments later, the aircraft collided with terrain in the Vosges mountains near La Bresse.
The investigation
The investigation focused on the wreckage, which was recovered from a mountain slope at approximately 3,000 ft. Analysis of the wreckage showed the aircraft struck the ground with high energy and a level wing attitude, with the engine still producing power at the moment of impact. The flight controls were found to be functional.
Investigators noted that the aircraft was not equipped with a GNSS receiver, and no electronic tablets or aeronautical charts were recovered from the site. Meteorological data revealed that the cloud ceiling in the area was as high as 6,000 ft, meaning the peaks of the Vosges mountains, which reach up to 4,500 ft, were obscured within the cloud layer. Furthermore, the investigation determined that the late departure time made it impossible to reach the destination before nightfall.
Findings
- The pilot's late departure prevented the flight from reaching Colmar before the onset of aeronautical night.
- Weather conditions along the route made maintaining VFR flight nearly impossible due to the cloud layer obscuring the terrain.
- The accident was driven by insufficient flight preparation and a strong desire to reach the intended destination.
- A probable excess of confidence regarding the pilot's ability to operate in degraded weather conditions contributed to the decision to continue the flight into IMC.