What happened
On February 5, 2009, a Morane Saulnier MS 504, registration F-AZMD, was performing a local flight when it veered off the runway during landing at Clermont-Ferrand. While on final approach to runway 08, the pilot received wind information from the controller indicating a 12-knot wind from the south. Upon touchdown, the aircraft experienced a sudden veer to the right, exiting the paved surface approximately 100 meters after the wheels made contact with the runway.
As the aircraft moved onto the grass, the pilot managed to avoid one concrete manhole protruding about 15 centimeters from the ground. However, the aircraft struck a second concrete structure, causing the left landing gear to break. This impact caused the aircraft to settle onto the ground, leading the left wingtip to strike the surface, resulting in heavy damage to the aircraft.
The investigation
The investigation focused on the accuracy of the wind data provided to the pilot and the state of the runway surroundings. Investigators determined that the wind information provided by the controller was derived from a repeater in the control tower, which received data from a sensor located approximately 2,000 meters from the landing point. Due to the local terrain south of the aerodrome, wind readings from this sensor can be significantly lower than the actual conditions experienced during landing, particularly when using runway 08.
Furthermore, the investigation examined the presence of the concrete manholes within the runway safety area. It was noted that these structures were located within the runway strip/servitudes and that the local civil aviation authority had previously requested that the aerodrome manager perform leveling work to mitigate such hazards.
Findings
- The primary cause of the excursion was the transmission of unrepresentative wind information, as the reported 12-knot wind did not accurately reflect the actual wind conditions encountered during the landing.
- The wind sock located near the threshold of runway 08 provided insufficient information for the pilot to accurately assess the wind direction and intensity.
- The presence of unlevelled concrete manholes within the runway safety area contributed to the severity of the damage after the initial excursion.