What happened
On the morning of April 22, 2011, a Robin DR1050, registration F-BMPK, departed from the Annecy-Meythet aerodrome for a flight to Bellegarde. Shortly after takeoff, the pilot experienced engine vibrations and performed a 180-degree turn to return to the airfield. During the subsequent approach to the paved runway 04, the pilot changed his intention to use the grass runway. However, during the final approach, he changed his mind again, attempting to land on the paved runway. The aircraft overran the runway end to the right, where it collided with the aerodrome perimeter fence. The aircraft was destroyed, and the pilot sustained injuries.
The investigation
The investigation focused on the cause of the engine vibrations and the pilot's decision-making process. Investigators discovered that the exhaust manifold had been repaired six days prior in Bourg-en-Bresse following a previous in-flight failure. An examination of the engine revealed that the vibrations were caused by the installation of an incorrect exhaust manifold.
Furthermore, the investigation revealed that during a flight the previous day, the pilot had detected carbon monoxide in the cockpit after a control patch changed color. Although the pilot and co-owner had agreed to ground the aircraft until a full exhaust inspection was completed, the pilot decided to fly the aircraft the following day to meet an instructor in Bellegarde for a license renewal.
Findings
- The engine vibrations were caused by the installation of an incompatible exhaust manifold.
- The vibrations did not physically impair the engine's operational performance.
- The pilot's decision-making was characterized by inconsistent intentions regarding the landing surface.
- The presence of carbon monoxide in the cabin during previous operations may have contributed to impaired judgment.