What happened
On June 19, 2015, a Robin DR400-160, registration F-GJBO, was conducting a local flight involving several stops between Saint-Brieuc Armor and Ploermel Loyat. The aircraft was carrying a pilot and three passengers. During the approach to the unpaved grass runway 10 at Ploermel Loyat, the pilot encountered moderate turbulence caused by thermal activity and wind gusts. To maintain the descent profile despite these disturbances, the pilot increased engine power on short final.
This resulted in an excessive airspeed upon touchdown, causing the aircraft to land beyond the first third of the runway. As the aircraft continued down the grass strip, the pilot realized the aircraft could not be stopped before the runway end. In an attempt to avoid an overrun, the pilot initiated a go-around by applying full power. However, the aircraft lacked sufficient altitude to clear a nearby rapeseed field at the end of the runway, leading to an immediate impact and the aircraft coming to a halt in the field. There were no fatalities or injuries among the four occupants, though the aircraft sustained damage.
The investigation
The BEA examined the aircraft's configuration, the meteorological conditions, and the pilot's decision-making process. Investigators noted that the aircraft's flaps were in the landing position at the time of the accident. The investigation also reviewed the airfield's characteristics, specifically the 800-meter grass runway and the presence of thermal turbulence generated by nearby contrasting terrain, such as quarries and fields.
Findings
- The pilot's decision to initiate the go-around occurred too late.
- The pilot experienced a loss of control over key flight parameters on two occasions: first, due to turbulence causing excessive speed on final approach, and second, when realizing the aircraft could not stop on the grass surface.
- The pilot's assessment of the aircraft's ability to decelerate on the dry grass was inaccurate, likely due to the low friction of the surface and the runway slope.
- The go-around was likely unsuccessful because the aircraft did not accelerate sufficiently, possibly because the engine remained in a low-power setting or the pilot failed to properly reconfigure the aircraft due to haste.
- The investigation highlighted that failing to maintain a stabilized approach—specifically regarding airspeed and descent path—prevented the pilot from having sufficient time to either divert or plan a proper second approach.