Background
On 14 December 2021, at 13:59 local time, a pilot departed Sion airfield (LSGS) alone aboard a single-engine Robin DR-400/140 B, registered as F-HLLD. The flight was conducted under visual flight rules (VFR) as a private operation. The aircraft was owned by NSBC International and operated by Groupe de Vol à Moteur de l'Aéro-Club du Valais.
Incident
The pilot flew over Col du Pillon to Saanen airfield (LSGK), intending to land on runway 26. At 14:21, during the first final approach, the pilot judged the altitude as too high and initiated a go-around. A second attempt also resulted in a go-around for the same reason. On the third final approach, the pilot found the approach satisfactory and decided to land.
The pilot crossed the runway threshold at approximately 50 ft above ground with full flaps and a ground speed of 93 kt. The pilot noted the high approach speed but considered it acceptable given the 1400 m runway length. Over the displaced threshold, providing 1040 m of available landing distance, the ground speed was 83 kt. The aircraft touched down abeam the operations buildings, with about 550 m of runway remaining and a ground speed of 65 kt.
The runway was partially covered with snow and ice. The pilot was unable to stop the aircraft within the remaining runway. F-HLLD overran the runway end and became stuck in the adjacent snowfield.
According to the pilot, visibility at the beginning of the runway was better than toward the end; the runway end was not discernible through haze when crossing the threshold.
Analysis
The calculated landing distance per the flight manual, assuming maximum landing mass, a speed of 63 KIAS at 50 ft and 51 KIAS at touchdown, a dry hard surface, and maximum braking, is approximately 400 m from 50 ft and 200 m from touchdown. The pilot's actual approach speed (approximately 90 KIAS) exceeded the recommended 63 KIAS by about 27 kt.
The report notes that such excess speed significantly lengthens the flare and landing roll. In this case, the aircraft touched down in the second half of the runway at a speed more than 10 kt above the manufacturer's recommended touchdown speed. Given the contaminated runway conditions, stopping within the remaining distance was not possible.
Probable Cause
The pilot's decision to continue the unstabilized final approach under challenging visibility conditions until landing was therefore not safety-conscious.
Recommendations
A separate paragraph for recommendations is not included as the source does not provide any beyond the analysis.