Overview
On 16 March 2007, a glider accident occurred involving a Blanik L-13A, registration S5-7106, operated by Aeroklub Josip Križaj Ajdovščina. The aircraft was destroyed upon impact with tree crowns on the slope of Moščančarski hrib (1356 m) near Ajdovščina. The pilot, a Slovenian national born in 1970, held a valid glider pilot license and medical certificate. He was not injured in the accident.
Flight Sequence
The pilot departed from Ajdovščina airfield at 13:05 local time on a soaring flight. The glider was towed to 600 m QFE (height above the airfield) before releasing the tow rope and beginning independent soaring. The pilot climbed to an altitude of 1600 m in the area between the Hublja spring and Kovk hill. He then continued toward Kucelj hill (1237 m) and later toward the Golaki range. While flying above the slope between Mali Golak (1480 m) and Moščančarski hrib, the glider began losing altitude rapidly. Despite the pilot's efforts to avoid a collision, the aircraft struck tree crowns at 14:20 local time and became lodged in the trees. The pilot removed the canopy and exited the glider, then radioed the club manager in Ajdovščina to report the accident location.
Aircraft Information
The glider was a Blanik L-13A, serial number 026238, manufactured in 1976 by LET UH. Hradište – Kunovice, ČSSR. It was registered in Slovenia (S5-7106) since 6 May 1993 with a valid Certificate of Airworthiness. The total time on the airframe was 5373 hours and 28 minutes. The owner was Aeroklub Edvard Rusjan Nova Gorica.
Pilot Information
The pilot was a 36-year-old Slovenian citizen (born 1970). He held a glider pilot license issued on 11 May 1993, valid until 6 April 2007. His last proficiency check consisted of two control flights on the day of the accident. He had a valid Class 2 medical certificate, with his last general medical examination on 4 April 2005 and an electrocardiogram on 13 March 2003. His total flight experience was 190 hours and 57 minutes, with 10 hours and 27 minutes in 2006 and only 9 minutes in 2007 prior to the accident.
Meteorological Conditions
The weather at the time of the accident, as provided by the Slovenian Environment Agency, showed visibility over 10 km, mostly clear sky with up to 2/8 low cumulus clouds, temperature 20°C in the valley and about 14°C at 1000 m altitude. Valley wind in the Vipava Valley was around 5 knots with gusts up to 10 knots; on Otlica (965 m) a slope wind of about 5 knots with gusts to 12 knots was recorded. No strong prevailing winds were present over the broader area. Turbulence was associated with weak to moderate thermal updrafts and downdrafts.
Damage and Injuries
The glider and its equipment were destroyed (100% damaged) and considered beyond repair. A small number of trees were damaged by the impact. No other property damage occurred. The pilot was uninjured; no other persons were involved.
Communication and Navigation
The glider was equipped with a VHF-COMM Dittel FSG 15 radio. Communication was established on frequency 123.500 MHz. The pilot reported the accident via radio immediately after the collision. The aircraft had two LUN-type compasses, one in the front and one in the rear cockpit.
Investigation
The investigation was conducted by the Sector for Aircraft Accident and Incident Investigation of the Ministry of Transport of the Republic of Slovenia. The commission consisted of Roman Rovanšek (chief investigator) and Viktor Bečan (member). The report includes facts, analysis, conclusions, and safety recommendations, but the provided text does not specify a probable cause.