Occurrence
On Saturday, 6 August 2022, at 13:45 UTC, a Schleicher K6Cr sailplane was launched by winch from Runway 11 at the aerodrome of Tournai/Maubray (EBTY). The aircraft was the 17th sailplane to take off that day, and its first flight of the day. Following pre-flight checks with the pilot owner, the pilot boarded, prepared the flight, and radioed the winchman. The winch launch commenced, and the sailplane accelerated along the runway. Immediately after becoming airborne, it climbed with a notably high pitch attitude. During the climb, observers noticed the aircraft drifting slightly to the left with a left wing down attitude. The pilot appeared to correct this, but then the right wing dropped and the sailplane entered an incipient spin at a height of approximately 100 meters (300 feet) above ground, equivalent to about seven times the wingspan. The sailplane completed one and a half clockwise rotations before impacting the ground. The impact destroyed the aircraft and caused fatal injuries to the pilot.
Contextual Information
The pilot was a 48-year-old Belgian national holding a Sailplane Pilot License first issued on 28 September 2021, with ratings for aerotow and winch operations. His medical certificate (LAPL) was valid until 14 September 2023. His total flying experience comprised 179 flights and 58.3 flight hours, including 142 winch take-offs. In the 90 days prior, he had completed 6 flights, 5 with winch starts. His last flight before the accident was on 23 July 2022 in an ASK-21 with a winch start. This was his first winch launch in a Ka6; he had previously flown the similar Ka8 on winch launches.
The aircraft, a Schleicher Ka6 CR (serial 6132, built 1963), was registered with the Belgian Civil Aviation Authority. Its last Airworthiness Review Certificate was issued on 1 May 2022 and valid until 24 May 2023. The empty mass was 208 kg, and maximum take-off mass 300 kg. The pilot's weight was estimated between 75 and 85 kg. The aircraft was equipped with a center-of-gravity winch hook (TOST Europa G72) slightly offset to the left, causing a slight yaw to the right during cable pull. The elevator was fitted with a Flettner tab that functioned as both an anti-servo and trim tab, adjustable via a cockpit lever.
Weather conditions were dominated by a high-pressure system. METAR reports from nearby aerodromes (Chièvres, Lille-Lesquin, Kortrijk) indicated variable winds from the northeast at 7-10 knots, with some variation. The aerodrome has a single grass runway 11/29 of 640 m length and 18 m width, elevation 153 ft.
Investigation
The investigation was conducted by the Belgian Air Accident Investigation Unit (AAIU) as a limited-scope, fact-gathering effort. The wreckage was reconstructed and inspected on 11 August 2022. The fuselage was broken into four main sections, the cockpit disintegrated, and both wings severely damaged. The control rods were weakened but still in place. The canopy was broken but the cockpit locking handle was in the locked position. The winch used was a KLu T2 model with about 300 hp. No flight recorder was installed; a witness video was available.
Injuries and Damage
The pilot sustained fatal injuries. The aircraft was destroyed.