What happened
On March 20, 2016, at Zábřeh Airport (LKZA), a pilot was performing circuit training flights. Following a successful initial solo flight, the pilot began a second flight at 11:22 UTC, launched via winch from runway 28L.
During the fourth turn of the circuit, the pilot extended the flaps. During this maneuver, the pilot accidentally bumped the airbrake lever, causing the brakes to partially deploy. The pilot misidentified the resulting increase in sink rate as an increase in headwind. Realizing the aircraft would not reach the runway, the pilot opted to land on a grassy strip north of the runway axis to avoid a plowed field. During the landing roll, the rear of the glider struck concrete panels located near a service road, causing damage to the tail section and the horizontal stabilizer. The pilot was uninjured.
The investigation
The ÚZPLN examined the flight sequence, the aircraft's maintenance history, and the meteorological conditions at the time of the accident. The investigation focused on the pilot's actions during the configuration of the aircraft and the subsequent decision-making process regarding the landing site. The investigation also reviewed the physical damage to the L 13A Blaník, registration OK-2718, and the presence of the obstacle at the landing site.
Findings
- The pilot was qualified and medically fit for flight.
- The aircraft was airworthy and had undergone a recent annual inspection.
- While manipulating the flaps, the pilot accidentally disengaged the airbrake lever, causing the brakes to extend.
- The pilot failed to verify the position of the airbrake lever after the maneuver.
- The pilot incorrectly attributed the increased descent rate to changing wind conditions.
- The landing was forced due to the increased sink rate caused by the partially deployed airbrakes.
- The damage to the L 13A Blaník was caused by contact with concrete panels acting as a fixed obstacle.