What happened
On June 9, 2008, a Qualt 201J ultralight aircraft, registration OK-JUU 44, crashed in a park near the village of Vokšice, Czech Republic. The flight was being conducted by a pilot who had recently completed instructor training, accompanied by an experienced instructor. The purpose of the flight was to practice handling non-standard situations from the instructor's seat, specifically focusing on improving techniques for managing unusual flight conditions.
During the flight, the aircraft was observed by several witnesses near the Jičín airport area. Witnesses reported that the aircraft initially reduced engine power to idle and increased its angle of attack, likely attempting to reach a stall speed. This maneuver led the aircraft into an autorotative state. Witnesses noted that the aircraft underwent several rapid rotations with a vertical axis. Despite apparent attempts to recover—including increases in engine power that momentarily changed the aircraft's pitch—the aircraft continued to rotate steeply toward the ground. The aircraft eventually struck trees in a local park at a high angle, resulting in the fatal deaths of both crew members and the total destruction of the aircraft.
The investigation
The ÚZPLN investigation examined the aircraft wreckage, witness testimonies, and the pilot's training records. Investigators found no evidence of mechanical failure in the engine or the flight control systems; the engine was likely operating at idle power just before impact. The investigation also reviewed the aircraft's weight and balance, noting that the aircraft was significantly overweight at the time of takeoff. Furthermore, the investigation analyzed the flight manual, which prohibited aerobatic maneuvers, including intentional spins, and lacked specific procedures for recovering from unintentional spins.
Findings
- The aircraft was overweight, exceeding its maximum takeoff weight by approximately 30 kg due to the combined weight of the crew and fuel.
- The crew intentionally entered a flight regime (unintentional spin/autorotation) that was prohibited for this category of ultralight aircraft.
- The crew failed to recover from the developed autorotative state.
- The pilot, while highly skilled in standard operations, lacked specific training in aerobatics and spin recovery.
- The flight manual did not provide necessary guidance for recovering from unintentional stalls or spins.