What happened
On June 20, 1998, at approximately 16:20 local time, a LAK-12 “Lietuva” glider, registration LY-GDH, was involved in an accident during takeoff at Pociūnai Aerodrome. The flight was being conducted by a member of the Kaunas District Aviation Sports Club as part of a routine flight within the aerodrome vicinity. Meteorological conditions were reported as good and favorable for flight.
The pilot initiated the takeoff roll on an unpaved section of the aerodrome, following a W-35 “Wilga” aircraft. As the glider accelerated, it encountered a slight rightward slope, causing the wing to scrape through the grass. At a speed of approximately 60 km/h, roughly 80 to 100 meters from the start of the takeoff roll, the right wing encountered taller grass reaching heights of up to 0.5 meters. The resulting increased resistance on the right side triggered an uncontrolled ground loop around the vertical axis.
At nearly the same moment that the rotation began, the glider pilot and the tow aircraft pilot engaged the towline. The sudden braking of the right wing caused the left wing to accelerate, lifting the glider to an altitude of approximately 2 meters before it struck the ground at a shallow angle with its nose. The impact involved the nose, the landing gear wheel, and the tail support.
There were no injuries to the pilot or any other persons during the event.
The investigation
The investigation examined the takeoff surface, the aircraft's structural condition following the impact, and the actions of both the glider and tow aircraft pilots. The inspection of the LAK-12 “Lietuva” revealed several points of damage, including a broken wheel lever, structural deformation in two locations, damaged stabilizer edges near the trailing edges, and a broken canopy mounting bracket. The investigation determined that the repairs required could only be performed in factory conditions.
Findings
The accident was caused by the following factors:
- Pilot error, specifically failing to disconnect from the towplane in a timely manner.
- Improper selection of the takeoff site, as the chosen area contained uneven terrain and tall grass that interfered with the wingtip.
- Increased resistance on the right wing due to the uneven surface and vegetation, leading to the loss of directional control.