What happened
On June 6, 2004, at 15:44 UTC, an Zephyr 2000 ultralight aircraft, registration OK-HUQ 30, crashed in the municipality of Kravaře during a recreational flight. After flying over the Velké Hoštice airfield, the pilot executed a left climbing turn followed by a sharp transition into a right descending turn. During the transition to level flight, the aircraft struck the ground.
The impact was severe, resulting in the total destruction of the aircraft. The right wing separated from the fuselage, the nose landing gear was dislodged, and the fuselage sustained heavy damage. The impact caused the fuel tank to rupture, spilling approximately 10 to 15 liters of fuel onto the ground. The crash resulted in one fatality (the passenger) and one serious injury (the pilot).
The investigation
The ÚZPLN investigation established that the aircraft was significantly overweight at the time of the accident. While the maximum takeoff weight for the aircraft is 450 kg, the actual weight at the moment of the crash was approximately 519.5 kg, exceeding the limit by roughly 69.5 kg (an overload of 15.4%).
The investigation also identified several secondary findings:
- The passenger was likely not properly restrained by a seatbelt at the time of impact.
- An unidentifiable pyrotechnic rescue system was installed in the fuselage but was not marked with the required warning triangle.
- The aircraft lacked required regulatory markings, such as notices stating that the aircraft is not subject to CAA approval and that acrobatic maneuvers are prohibited.
- The aircraft's stall speed had increased due to the overload, rising from 76 km/h to approximately 82.5 km/h.
Findings
The primary cause of the accident was the execution of a descending maneuver in a turn while the aircraft was overweight, at an altitude that did not allow for the safe completion of the maneuver. Contributing factors included the pilot's failure to maintain the minimum required altitude of 150 meters during the maneuver and the likely failure to properly secure the passenger.