What happened
On June 7, 2014, a Centrair 201 Marianne glider, registration F-CGMH, was performing a winch launch at the Troyes-Barberey aerodrome for a pleasure flight. During the climb, at an altitude of approximately 130 meters and a speed of 120 km/h, the synthetic winch cable snapped.
Following the cable break, the pilot experienced a rapid drop in airspeed. To maintain control, the pilot pushed the nose down to regain an optimal approach speed of 110 km/h and deployed the airbrakes once the altitude dropped below 100 meters. To avoid obstacles at the end of the active runway, the pilot opted to land on the intersecting runway (runway 23). During the turn toward this runway, the right wing dropped, leading to a stall. The pilot responded by pushing the nose down to recover speed and retracted the airbrakes, but the aircraft's right wing struck the ground first, resulting in a collision that left two persons injured and the glider destroyed.
The investigation
The BEA examined the flight data from the aircraft's FLARM system and interviewed the pilot. The investigation focused on the mechanics of the cable failure and the pilot's decision-making process during the emergency. Investigators analyzed the condition of the synthetic Dyneema cable, which had been previously repaired using a splice technique. The investigation also reviewed the club's procedures for winch launch interruptions and cable maintenance.
Findings
- The primary cause of the cable failure was a defective splice within the synthetic cable, which had weakened the material at the repair point.
- The pilot's decision to execute a turn toward runway 23 likely resulted in a steep bank angle. This increased the load factor and stall speed, which, combined with the deployment of airbrakes, led to the wing drop and subsequent ground impact.
- The club lacked a formal, written procedure for managing winch launch interruptions and did not have a verification process for cable splice repairs.
- While the pilot had briefed the procedure for a cable break, the high-pressure nature of the intermediate altitude (between 100m and 200m) made rapid decision-making difficult.