Summary
A serious incident occurred on December 28, 2022, involving an SZD-48-1 "Jantar Std. 2" glider (registration SP-3719) during a descent after a wave flight. The movable part of the canopy separated from the aircraft, struck the tail, and fell in a residential area of Bielsko-Biała. The pilot landed safely without injury. The Polish State Commission for Aircraft Accident Investigation (PKBWL) conducted the investigation.
Flight History
The pilot, a 47-year-old male holding a valid Sailplane Pilot Licence (SPL), departed from EPBA (Bielsko-Biała/Aleksandrowice) at 09:47 LMT on a wave flight over the Silesian Beskids. After more than five hours, he returned to the vicinity of the airfield. While descending over the western part of Bielsko-Biała at approximately 800 m AGL, with speed about 120 km/h, he had extended the airbrakes and landing gear. Around 15:15 LMT, the movable canopy section rotated on its aft hinge and detached, hitting the tail surfaces. It caused damage to the paint on the horizontal and vertical stabilizers, dented the fuselage, and deformed the variometer pitot tube. The pilot did not notice the collision due to sudden noise and cold air entering the cockpit. He checked controls, declared an emergency, and landed safely at EPBA. The canopy was later found in a central residential area about 2.6 km northeast of the airport. No injuries or ground damage occurred.
Damage
The glider sustained minor damage: paint damage on leading edges of tail surfaces, scratches on the rudder, a dent in the fuselage near the hinge requiring workshop repair, and a deformed variometer tube. The canopy itself was completely destroyed upon impact.
Probable Cause
The PKBWL determined the cause as: the pilot inadvertently contacted and unlocked the right canopy locking lever while moving the landing gear lever forward, creating a gap between the canopy and fuselage.
Contributing Factors
Three contributing factors were identified: 1) slack in the canopy locking mechanism after closing and locking; 2) vibrations of the movable canopy part caused by superimposition of vibrations from the open airbrakes and surrounding air turbulence; 3) pilot fatigue, cold exposure, and reduced perception after a long high-altitude flight.
No safety recommendations were issued.