What happened
On July 18, 2019, during a student training session at the Aeroklub Lubelski flying club, two gliders were performing solo thermal flights. The first aircraft, an SZD-30 Pirat with registration SP-3914, departed via winch launch at 12:03 LMT. The second aircraft, an SZD-30 Pirat with registration SP-3652, followed at 12:11 LMT.
Both gliders eventually encountered a thermal column south of the Radawiec airfield. While circling in the thermal, the aircraft's flight paths intersected. The pilot of SP-3652 attempted to contact the other pilot via mobile phone, but received no response and subsequently exited the thermal to move toward a different sector.
At approximately 13:36 LMT, at an altitude of 1,100 meters near Palikije, the two gliders collided. The left wing of SP-3914 struck the lower fuselage of SP-3652 from below. The impact caused the fuselage of SP-3652 to break into multiple pieces, separating the cockpit and wings from the tail section. The pilot of SP-3652 was forced to perform an emergency parachute egress. During the exit, the pilot sustained one serious injury due to contact with the cockpit canopy and the airframe. The parachute deployed correctly, and the pilot landed safely in a field. The pilot of SP-3914 was able to maintain control and landed the aircraft safely back at the airfield.
The investigation
The PKBWL investigation examined the flight history, aircraft maintenance records, and the physical wreckage. The investigation relied on the testimonies of both student pilots and the analysis of impact marks on the aircraft. Investigators noted that the pilot of SP-3914 had released the air brakes and lowered the control stick shortly before the collision, which increased the aircraft's speed and caused it to descend into the path of the leading glider. Physical evidence, including red paint transfers on the left wing of SP-3914, confirmed the point of impact on the lower fuselage of SP-3652.