What happened
On October 4, 2020, a Sonex, registration LV-X628, was conducting a general aviation training flight departing from Posadas/Bonetti airfield in Parada Leis, Misiones. After approximately 30 minutes of flight in visual conditions, the pilot attempted a low-altitude flyby over the runway. During this maneuver, the aircraft's left wing struck an ultralight aircraft, registration LV-UX056, which was parked near the edge of the runway.
The collision caused immediate structural damage to the wing of the LV-X6 and rendered the aircraft uncontrollable. The Sonex entered a steep bank and plummeted to the ground, impacting the terrain with significant force. The impact was so violent that the engine was torn from the airframe. The accident resulted in the death of the pilot and serious injuries to the passenger.
The investigation
Investigators analyzed flight footage and eyewitness accounts to reconstruct the sequence of events. The evidence indicated that the pilot was not configured for a landing; the flaps were retracted, and the airspeed was higher than a standard approach. The investigation focused on the pilot's attention, noting that the crew was likely distracted by a group of people on the ground who were waving to the aircraft.
The investigation also examined the positioning of the parked aircraft. It was determined that the LV-UX056 was parked approximately 15 meters from the runway centerline, which violated regulations requiring a larger obstacle-free zone. Furthermore, the dark color of the parked aircraft helped it blend into the surrounding vegetation, which likely hindered the pilot's depth perception.
Findings
- The accident was caused by a low-altitude flight maneuver that violated minimum safety altitude regulations.
- The pilot's attention was fixated on the people on the ground, leading to a failure to detect the parked obstacle.
- The parked aircraft was positioned within the runway's obstacle-free zone, contrary to established safety standards.
- The visual characteristics of the parked aircraft made it difficult to perceive against the landscape.
Safety action
- There is a need for increased instruction regarding regulatory compliance for minimum safety altitudes within aero clubs.
- Emphasis should be placed on training regarding Threat and Error Management (TEM) and Safety Management Systems (SMS) to improve hazard identification during flight operations.