What happened
On August 20, 2015, during the Polish Junior Glider Championships, a SZD-48-1 Jantar Std 2 (registration SP-3224) operated by Aeroklub Jeleniogórski was participating in a 335 km triangle course. As thermal activity declined in the afternoon, the pilot initiated a water ballast dump to reduce weight. However, a significant amount of water remained in the left wing tank due to a malfunction.
As thermals dissipated, the pilot decided to perform an out-of-field landing near Nietków. After identifying a suitable field, the pilot approached with a trailing wind from the east. To prevent the aerodynamic brakes from catching on the tall flax crops, the pilot closed the brakes during the flare. During the landing roll, the glider's left wing struck the tall vegetation, causing the aircraft to pivot approximately 190 degrees around its vertical axis.
The investigation
The PKBWL investigation examined the flight data (IGC file) and the aircraft's condition following the incident. The investigation focused on the effectiveness of the ballast discharge, the landing approach parameters, and the impact of the high crops on the aircraft's stability during the roll.
Findings
- The left wing ballast tank failed to vent properly, leaving a substantial amount of water in the left wing.
- The aircraft's left wing struck high-standing crops during the landing roll, triggering the ground loop.
- The pilot performed the landing with a trailing wind component; the investigation noted that a headwind approach would have significantly reduced the ground speed and likely prevented the structural damage.
- The aircraft sustained damage to the left wing trailing edge and tip, the fuselage skin near the rear wheel, and the horizontal stabilizer fittings.