Incident Overview
On 18 July 2017, a student pilot was conducting his second solo thermal flight of the day in a SZD 30 Pirat glider. The incident occurred near Masłów, Poland. The pilot was unharmed, and the glider sustained damage to its fuselage skin.
Flight History
After takeoff at approximately 100 meters, the towing aircraft performed a left turn. According to the IGC flight data, the tow speed varied between 100 and 140 km/h, and vertical speed ranged from -1.5 m/s to +4.5 m/s. After leveling out on a westward heading, the tow speed fluctuated between 96 and 103 km/h, with vertical speed between -2 m/s and +4 m/s. The student reported that glider control felt difficult, leading him to believe the glider was damaged. He focused entirely on flying and did not monitor airspeed. At an altitude of about 250 meters and 2 km from the airfield, the tow plane began a right turn. During the first circle, the student heard an unusual noise and felt a loss of control, prompting him to release the tow line. Data suggests the glider encountered significant turbulence at that point.
Decision to Land
After releasing at approximately 350 meters, the student maintained a northwest heading. The supervising instructor radioed, noting the low altitude and ordering a return to the airfield. The student perceived excessive sink rate and abnormal control response, concluding he could not reach the airfield. He decided to land in an open field and informed the instructor, who confirmed the decision. The student chose a suitable landing site but realized during approach that the airbrakes were open. The landing was performed with a light tailwind and a slight overshoot, ending on a field boundary.
Damage and Injuries
During the rollout, the glider struck a protruding stone with its left fuselage side at low speed. This impact damaged the fuselage skin near the front skid and in the lower rear section. The student pilot suffered no injuries.
Cause
The investigation identified the cause of the incident as the student pilot unintentionally opening the airbrakes (or them being sucked open) during towing in turbulent air, leading to the off-airfield landing. The landing with an overshoot was also noted as a contributing cause.