Covering form of preliminary or final report
Back| Date of event: | 2022.02.12 |
|---|---|
| Incident number: | CZ-22-0050 |
| Report: | Final report |
| Place of event: | ATZ LKPL |
| Registration mark: | Accident |
| Weight category MTOM:: | <2250 kg |
| Type of operation: | Recreational and sport aviation |
| Plane / SFM: | Airplanes |
| Type of plane / SFM: | L-13 Blaník |
| Health effects of event: | Without injury |
| PDF document: |
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Description:
Description
On 12 February 2022, the AAII was notified of an accident of the L-13 Blaník glider at LKPL ATZ. The pilot with another person on board carried out a local thermal flight as part of organised flying. After a few turns performed south of the airport, he joined the circuit with the glider. Having finished the fourth turn, he extended brake flaps and continued approaching towards RWY 08L. Given a steep descent, the pilot secured the brake flaps again and closed also the wing flaps. The glider was below the level of the Háje hill and it was obvious that it would not be able to reach the airport. The pilot decided to make a left turn with the intention to land into the terrain. During this manoeuvre, the glider came into contact with the grown trees below the peak of a steep slope. The glider remained wedged in tree branches and the crew left the cabin by roping down.
The glider was heavily destroyed by the collision with an obstacle. The pilot was not hurt. The passenger was taken to the Faculty Hospital for examination because of his chest pain.
SUMMARY
Synopsis
The pilot with another person on board carried out a local thermal flight as part of organised flying. After a few turns performed south of the airport, he joined the circuit with the glider. Having finished the fourth turn, he extended brake flaps and continued approaching towards RWY 08L. Given a steep descent, the pilot secured the brake flaps again and closed also the wing flaps. The glider was below the level of the Háje hill and it was obvious that it would not be able to reach the airport. The pilot decided to make a left turn with the intention to land into the terrain. During this manoeuvre, the glider came into contact with the grown trees below the peak of a steep slope. The glider remained wedged in tree branches and the crew left the cabin by roping down.
The glider was heavily destroyed by the collision with an obstacle. The pilot was not hurt. The passenger was taken to the Faculty Hospital for examination because of his chest pain.
Factual Information
The pilot with another person on board (hereinafter the passenger) carried out a local thermal flight as part of organised flying at LKPL. After take-off at 13:19 from RWY 26 in aerotow behind the Dynamic UL aircraft, the glider was smoothly climbing up to the altitude of 900 m above the airport. After release of the glider from the towing aircraft, the pilot made a few turns in the area south of the airport and then joined the right RWY 08L circuit. The third circuit turn was initiated at the altitude of 260 m AAL. Having finished the turn, the pilot extended wing flaps and continued flying on a circuit.
The critical situation occurred after completion of the fourth turn, when the pilot extended brake flaps and continued approaching towards RWY 08L. Given a steep descent, the pilot secured the brake flaps again and closed also the wing flaps. The glider was already below the level of the Háje hill and it was obvious that it would not be able to reach the airport. The pilot decided to make a left turn with the intention to land into the terrain below the slope on the field near the municipal district Koterov. During this manoeuvre, the glider came into contact with the grown trees below the peak of a steep slope west of the Koterov observation point. The glider remained wedged in tree branches at the altitude of about 6 meters.
Analyses
OGN Tracker records clearly show that the pilot joined the right RWY 08L circuit in the downwind position at the altitude of 325 m AAL. He initiated the third circuit turn at the altitude of 260 m AAL and, having finished the turn, continued in the 350° heading into the fourth turn, which he initiated at the altitude of 160 m AAL. Having completed the turn at the altitude of 100 m AAL, the glider was located above an extended axis of the runway at the distance of approx. 1,200 m from RWY 08L threshold marks and approx. 600 m northwest of the Háje hill. At this phase of the flight, the glider flew into the wind rotor caused by the southeast vortex flow through an obstacle. At a distance of approx. 1 km far from the airport, when the glider was located above the valley of the Úslava river and given the flight altitude of approx. 50 m AAL (approx. 150 m above the valley), it was obvious that it would neither be able to reach the airport of planned landing nor fly over the peak of a steep slope below the Koterov observation point. Pilot’s late decision to land into the terrain caused a contact of the end of the right wing with the treetops of fully grown trees when performing a left turn in close proximity to the slope. Having crashed into a height obstacle, the glider remained hanging approx 6 m above the ground, with its nose and tail part wedged in the branches of fully grown trees at about 60° left roll. Upon a crash into an obstacle, the leading edge of the end of the right half of the wing, which was partially broken off the fixture in the centre plane, was torn. As the glider crashed into tree branches, the pilot cab canopy was destroyed, the tail part was deformed at the mounting point of the vertical stabilizer, and the fuselage was partially broken in the area behind the centre plane.
Conclusions/Causes
The accident was caused by the late decision of the pilot to interrupt an approach to the airport and his subsequent failed manoeuvre before forced landing into the terrain when the glider crashed into a height obstacle.
Given the cause of the accident, the AAII issues no safety recommendations.Attached final report in PDF file is in original Czech language.