What happened
On March 16, 2007, at approximately 14:20 local time, a Blanik L-13 A glider, registration S5-710 and 06, was conducting a recreational soaring flight near Ajdovščina, Slovenia. The flight began with a tow from Ajdovščina airfield, with the pilot releasing the tow cable at an altitude of 600 m QFE.
After climbing to between 1600 m and 1700 m using thermal lift, the pilot transitioned into a glide toward the Golaki hills. While navigating the terrain between Mali Golak and Moščančarski hrib, the aircraft began a rapid descent. The glider struck the treetops on the slope of Moščančarski hrib with a high positive glide angle and a nose-up attitude of approximately 45 degrees. The impact caused the aircraft to slide through the canopy, striking several tree trunks, which resulted in the 100% destruction of the aircraft. The pilot was able to exit the wreckage unharmed and notified the aeroclub via radio.
The investigation
The investigation examined the technical condition of the aircraft, the flight path reconstruction, and the meteorological conditions at the time of the accident. Investigators analyzed the extensive damage to the airframe, noting that the left wing partially detached from the fuselage and the horizontal stabilizer was severely damaged. The reconstruction of the flight path was based on the pilot's statements, physical evidence at the crash site, and an analysis of the wind conditions, which included light to moderate thermal activity and a valley breeze of approximately 5 to 10 knots.
Findings
- The primary cause of the accident was insufficient altitude maintained while flying over terrain, which led to the loss of control and subsequent impact.
- The aircraft sustained catastrophic structural failure, including the separation of wing components and fuselage deformation.
- Meteorological conditions were generally clear with visibility exceeding 10 km, though the pilot'1s flight path lacked the necessary altitude to clear the ridge safely.