What happened
On September 28, 2013, during the "AVIATIK ŠOU 2013" airshow at the SLZ Bojkovice airfield, an Antonov AN-2, registration OM-PYB, was taxiing to its assigned parking position. After completing a flight demonstration, the pilot taxied toward a designated parking area. To execute a 180-degree turn and position the aircraft correctly within the parking row, the pilot increased engine power to overcome resistance from the soft, saturated grass surface.
As the pilot applied power, the resulting propeller blast struck a nearby Zephyr 200 and OK-HUG 06 ultralight aircraft parked approximately 30 meters behind the AN-2. The force of the airflow caught the ultralight, flipping it onto its back. The incident resulted in significant damage to the Zephyr 200, including a broken cockpit frame, a cracked canopy, and damage to the propeller cone and wing structure. No injuries were reported.
The investigation
The ÚZPLN investigation established that the pilot of the AN-2 was experienced and aware of the propeller blast effects, but had performed a similar taxi maneuver earlier that day without incident. The investigation found that the pilot likely overestimated the ability of an event organizer, who was standing near the ultralight, to secure the parked aircraft against the wind.
Furthermore, the investigation revealed that the event organizer was conducting the public flight display without the required approval from the Civil Aviation Authority (ÚCL). The investigation also noted that the parking arrangements did not comply with established safety conditions for organizing public flight displays, specifically regarding the separation of aircraft types and parking procedures.
Findings
- The pilot increased engine power to facilitate a turn on a wet, muddy grass surface.
- The pilot underestimated the impact of the propeller blast on a nearby, unsecured object.
- The propeller blast was the direct cause of the ultralight aircraft overturning.
- The event organizer failed to follow safety regulations regarding aircraft parking and separation.
- The airshow was being operated without official authorization from the Civil Aviation Authority.