Accident Sequence
A single-engine aircraft departed Figari-Sud-Corse Airport on a positioning flight to Saint-Tropez-La Môle with one pilot and one passenger on board. Weather at the destination was poor, with a ceiling of 1,800 feet and rain. The pilot contacted Nice Approach and was cleared to descend to 6,000 feet and to report over EM for an approach to La Môle Airport Runway 24. During the final approach, the pilot was unable to establish visual contact with the runway and initiated a go-around procedure. Minutes later, he completed a second approach and landed the airplane 200 meters past the runway threshold at a speed of 136 knots. Spoilers were deployed, but the airplane could not stop within the remaining distance. It veered slightly to the left, departed the end of the runway, crossed a river, and came to rest against an embankment located about 100 meters past the runway end. The pilot escaped unhurt, while the passenger was slightly injured. The aircraft was damaged beyond repair.
Probable Cause
The official investigation determined that the landing distance of the airplane on a wet runway, as defined in the Airplane Flight Manual (AFM) performance tables, was not compatible with the length of runway available at La Môle Aerodrome. When preparing the flight, the pilot used the flight record provided by the operator ProAir to determine landing performance. The landing distance on a wet runway presented in the file increased that on a dry runway by 15%. However, the 15% increase on a wet runway can only be used in conjunction with the increase of 60% imposed in commercial operation; otherwise, it may be inappropriate. The resulting calculated value was, in this case, wrong and less than the value indicated in the aircraft flight manual. The pilot probably did not use the EFB application for the calculation of performance or the flight manual to verify this value. Thus, the pilot undertook the flight on the basis of erroneous performance values, without realizing that he could not land at this aerodrome if the runway was wet. In addition, during the final approach, the speed of the aircraft was greater than the reference approach speed, and the approach slope was also greater than the nominal slope, which resulted in an increase in landing distance. During the landing roll, the aircraft exited the runway longitudinally at a speed of 41 knots. The pilot failed to stop the aircraft before it collided violently with obstacles at the end of the track.
Contributing Factors
The investigation identified several contributing factors: the operator's use of the same operations manual for two different types of operations; the absence in the operations manual of a calculation method, coefficient, and safety margin for calculating performance in non-commercial transport; lack of knowledge by the pilot and the operator of the method of calculating landing performance in non-commercial transport; and the lack of indication in the operations manual that the landing performances at La Môle aerodrome are limiting in case of a wet or contaminated runway.