What happened
On 14 April 2018, during the fifth competition discipline of the International Flight Challenge Cup-Gliding 2018, two LS8-18 gliders collided near the Lietavska Svinna - Babkov area. The aircraft involved were registration SP-3893 (competition sign "A") and LY-GT0 (competition sign "P2").
At approximately 12:57 UTC, both gliders were maneuvering within a common upward flow. The pilot of the LY-GOT glider initiated a right turn at an altitude of 1,785 meters. Shortly after, the pilot of the SP-3893 glider began a similar right turn at an altitude of 1,794 meters, approximately 350 meters behind the first aircraft.
During the execution of the turn, the SP-3893 glider ascended above the LY-GOT glider. This change in relative position caused the pilot of the SP-3893 to lose visual contact with the other aircraft as the lower part of the cockpit canopy obscured the view. Consequently, the left wing of the SP-3893 struck the left wing of the LY-GOT at an altitude of 1,850 meters. The collision rendered both gliders uncontrollable, leading both pilots to bail out using parachutes. Both pilots landed safely with no injuries, though both gliders were destroyed upon impact with the terrain.
The investigation
The investigation examined the flight paths, the pilots' maneuvers, and the aircraft's technical status. Investigators reviewed the competition flight plans, the meteorological conditions, and the flight recorders (GNSS-FR) and FLARM traffic warning systems installed on both aircraft. The analysis focused on the sequence of the turn and the loss of visual separation between the two pilots while maneuvering in the upward flow.