What happened
On 4 August 2023, during the World Advanced Glider Aerobatic Championships at Torun aerodrome (EPTO), a collision occurred between a tow plane and a MDM-1M SoloFox glider, registration SP-80 and 00.
Following the agreed-upon procedure for the competition, the tow plane released the glider at an altitude of approximately 1,220 meters. After the release, the glider pilot turned toward the aerobatic zone axis to begin a flight sequence. However, the tow plane pilot did not immediately execute the pre-briefed 90-degree right turn to exit the zone. Instead, the tow plane maintained its heading for approximately 10 seconds, placing it on a collision course with the descending glider.
As the glider pilot began the first figure of the sequence, the right wing of the MDM-1M SoloFox struck the tow line. The line coiled around the aircraft's tail, becoming jammed in the gap between the fuselage and the right wing. This entanglement caused the elevator to become stuck in the full-down position. Realizing the loss of control, the pilot jettisoned the cabin fairing, unbuckled, and performed an emergency parachute jump. The glider subsequently impacted the ground, resulting in the destruction of the aircraft, while the tow plane sustained slight damage. No injuries were sustained by either pilot.
The investigation
The PKBWL investigation examined the flight patterns, radio communications, and the adherence to the pre-flight briefing protocols. The investigation reviewed video footage from both the glider cockpit and the competition organizers to reconstruct the sequence of events. The commission also analyzed the roles of the Flights Director and the Chief Contest Judge in monitoring the aerobatic zone occupancy.
Findings
- The tow plane pilot did not comply with the established traffic pattern agreed upon during the pre-flight briefing.
- The glider pilot failed to verify that the tow plane had cleared the aerobatic zone before initiating the sequence.
- The Flights Director did not monitor the aircraft'ability after the tow line release.
- The lack of height measuring devices (HMDs) led the pilots to attempt the sequence as quickly as possible to conserve altitude, reducing the margin for error.
- The Chief Contest Judge was unable to issue a warning because the collision maneuver and the start of the aerobatic sequence occurred almost simultaneously.