What happened
On June 5, 2005, during the first competition of the 50th Polish Glider Championships in the Standard Class, a pilot flying an SZD-48-3 Jantar std 3 was participating in a cross-country task. The flight conditions were challenging due to wind speeds ranging from 18 to 26 km/h, with gusts up to 60 km and significant Cumulonimbus cloud activity. After traveling approximately 140 km, the pilot encountered a loss of thermal lift, making it impossible to continue the task.
The pilot decided to perform an off-field landing in an area near Sarbinowo, where several other gliders from the competition were already landing. The pilot initiated a 180-degree turn at an altitude of 140 m AGL. Flight logger data indicates that by the fourth turn, the altitude had decreased to 70 m AGL. During the final approach, the pilot executed a sideslip to alter the approach profile. However, due to excessive vertical speed and the aircraft's inertia, the landing lacked a proper flare phase. Seven seconds before the aircraft came to a stop, the vertical speed was recorded at -4.5 m/s. The glider struck the ground nose-first and underwent a nose-over, resulting in a total loss of the aircraft due to irreparable structural damage.
The investigation
The PKBWL investigation focused on the flight path recorded by the logger, the pilot's decision-making regarding the landing maneuver, and the aircraft's weight configuration. The investigators examined the structural damage, which included a crushed forward fuselage, a broken and detached tail boom and stabilizer, deformed main frame geometry, and broken control surfaces. The investigation also reviewed the presence of water ballast remaining in the aircraft's tanks at the time of the accident.
Findings
- The primary cause of the accident was the execution of an inappropriate landing maneuver; the pilot performed a deep sideslip at a low altitude when a flat approach would have been more suitable for correcting errors or responding to changing conditions in unknown terrain.
- The presence of remaining water ballast in the tanks acted as a contributing factor, increasing the aircraft's weight, wing loading, and inertia.
- The pilot's management of the water ballast was deemed improper and showed a lack of adherence to established procedures, as the remaining weight was unnecessary for the landing.