What happened
On May 8, 2017, a VSO-10 glider, registration OK-1506, was performing a training flight at Jaroměř Airfield (LKJA). The pilot, who had been serving as a radio dispatcher earlier that day, was executing a series of maneuvers intended to practice landing within a restricted area.
After completing the fourth circuit leg on runway 14, the pilot deployed the air brakes fully. Noticing that the aircraft was not descending sufficiently due to a crosswind component, the pilot reduced the indicated airspeed to approximately 80 km/h and attempted a short slip to increase the sink rate and adjust the landing distance. During the slip, the pilot applied left rudder and right aileron. The aircraft began to deviate from the intended path, and in an attempt to correct the heading, the pilot increased the right aileron input. This maneuver caused the right wing to drop, leading the glider into a right-hand spin. The aircraft struck the ground in a field of tall beets, resulting in the destruction of the glider and one serious injury to the pilot.
The investigation
The ÚZPLN investigation examined the aircraft's maintenance history, flight data from the OGN tracker, and the pilot's statements. The investigation confirmed that the VSO-10 was airworthy, with its most recent 100-hour inspection completed in April 2017. The aircraft was equipped with a functional emergency parachute.
Analysis of the flight path showed that the aircraft's descent rate increased significantly during the final moments of the flight. The investigation also reviewed the pilot's experience, noting that while the pilot was highly experienced in gliders, this was a relatively new type of aircraft for them. The physical inspection of the wreckage revealed that the impact caused the nose to shatter and the right wing spar to fail, resulting in the separation of the right wing from the fuselage.