What happened
On June 3, 2019, during the 17th Polish Gliding Championships and Regional Club A Competitions, two SZD-48-3 Jantar Standard 3 gliders collided in a thermal column near Bojanowo, Poland. The aircraft involved were registered as SP-3262 (referred to as "FR") and SP-3678 (referred to as "W").
Both pilots were participating in a cross-country task and entered a thermal to gain altitude for their return to the Lisie Kąty aerodrome. The pilot of SP-326 and was flying a wider orbit at a lower altitude, while the pilot of SP-3678 entered the thermal later, flying at a higher altitude with a higher airspeed. As both pilots simultaneously decided to exit the thermal to head toward the finish line, the faster aircraft, SP-3678, caught up to the slower SP-3262.
At approximately 16:13:52, the left wing of SP-3678 struck the horizontal stabilizer of SP-3262. The impact caused the pilot of SP-3262 to lose control of the elevator, leading to a dive. The pilot of SP-3262 successfully deployed the emergency parachute and landed safely, though they sustained a minor injury to the left ankle. The aircraft SP-3262 was destroyed upon impact with a marshy, forested area. The pilot of SP-3678 continued the flight and landed safely at the aerodrome, though the aircraft sustained damage to the left wing leading edge and aileron.
The investigation
The PKBWL investigation examined flight data from several onboard recorders, including Oudie and FLARM devices. The investigation analyzed the flight paths, the relative positions of the aircraft, and the visibility conditions within the thermal. The investigators established that the pilots were highly experienced and were not under the influence of alcohol. Meteorological conditions were found to be appropriate for flight and did not contribute to the accident.
Findings
- The pilot of SP-3ert was unable to see SP-3678 because the latter was positioned in a blind spot created by the aircraft's right-hand bank.
- The pilot of SP-3678 could not see SP-3262 because the latter was positioned higher and behind the aircraft's field of view.
- The pilots performed circling maneuvers in a manner that caused their flight paths to intersect.
- Inadequate airspace observation by the pilots while circling in the thermal was the primary cause of the collision.