Accident to the Jonker JS1 registered ZS-GEO on 25/05/2021 at Château-Arnoux Saint-Auban (Indre)

Cat. 3 investigation report: report concerning an occurrence with limited consequences, based on one or more statements not independently validated by the BEA.

This is a courtesy translation by the BEA of the Final Report on the Safety Investigation published in December 2021. As accurate as the translation may be, the original text in French is the work of reference.

Note: The following information is principally based on statements made by the pilot. This information has not been independently validated by the BEA.

1 - HISTORY OF THE FLIGHT

The pilot carried out a towed take-off from Château-Arnoux-Saint-Auban airfield at about 13:50 for a local flight.
After just over four hours of flight, he joined the circuit to land on axis 020°. During the downwind leg, he extended the flaps to the L position^[1], and the landing gear.
A person on the ground indicated on the radio that the wind was from 325° at 15 kt[2]. During the final approach and landing, the glider’s speed was 120 km/h. On landing, the glider touched down hard and bounced twice. On the second bounce, the pilot lost control of the glider. The glider yawed and rolled to the left, made a ground loop and came to rest facing south-west.
The rear section of the glider fuselage was ruptured and there was damage to the wing tip wheels. 

2 - ADDITIONAL INFORMATION
2.1 Aerodrome information

Château-Arnoux-Saint-Auban aerodrome is an uncontrolled airfield where the landing distance available is approximately 1,200 m on the main axis 022°.

2.2 Glider information

According to the flight manual, the flaps can be extended to six different positions: 1, 2, 3, 4, 5 and L.
The aerodrome circuit is flown with the flaps extended to positions 3 to 5 (+5° to +16.7°). For a short landing, the flaps can be set to L (+20°) on final approach.
In moderate crosswind conditions, the flaps should be set to position 4. The flight manual does not specify a crosswind speed range in which this configuration should be adopted.
In strong crosswind conditions, greater than 14 kt, the flaps should be extended to position 3.

2.3 Pilot information

The 64-year-old pilot held a glider pilot licence issued in 1987. At the time of the accident, he had logged 1,440 glider flight hours, including three hours in the last 90 days.
He also held a PPL(A) private pilot licence and had logged 125 flight hours.

2.4 Pilot’s statement

The pilot explained that he had not flown this type of glider for two years. He stated that he had extended the flaps to the L position in the downwind leg because he wanted to reduce his workload on final approach. He added that this flap position could have decreased the effectiveness of the ailerons and could have contributed to the loss of control.
He added that another contributing factor might have been the choice of a landing path that was not in line with the wind though at this aerodrome, home-based glider pilots (as was his case) can adapt their landing path to land preferentially into the wind. 
The pilot explained that he usually flew between 80 and 100 hours per year, but that the COVID-19 restrictions had not allowed him to practice as much during the year of the accident. In hindsight, the pilot felt that it would have been beneficial to perform a runway circuit with the glider, or even to carry out a dual flight on another type of glider, before performing a local flight.