What happened
On August 16, 2023, at approximately 10:10 local time, a ZLIN Z326M, registration EC-MKQ, was involved in an accident at the Robledillo de Mohernando airfield in Guadalajara, Spain. The flight, a private local operation, began around 09:45 local time. Shortly after takeoff, the passenger began feeling unwell due to motion sickness.
In response, the pilot returned to the airfield and landed on runway 19. The aircraft was brought to a stop off the runway with the engine still running and the canopy open, a configuration intended to provide airflow to assist the passenger. As the passenger attempted to exit the aircraft in a hurried and disorganized manner, the pilot stood up and began to exit the cockpit to provide assistance. During this process, the throttle was inadvertently moved, causing the aircraft to accelerate forward for approximately 30 meters until it struck the airfield's perimeter fence. The impact caused the pilot to fall from the wing onto the ground.
The investigation
The investigation examined the sequence of events following the passenger's sudden attempt to unbuckle restraints and exit the cockpit. Investigators analyzed the cockpit layout, noting that the throttle control is located on the left side of the cabin. While the passenger suggested the movement may have been caused by their knee, the investigation considered that the movement likely resulted from the passenger using their hands to push against the controls while struggling to exit.
Technical inspections of the ZLIN Z306M revealed no mechanical deficiencies that contributed to the event. The investigation focused on the pilot's actions during the period when the engine was still operational and the aircraft was unattended.
Findings
- The pilot failed to follow standard operating procedures by exiting the aircraft without first shutting down the engine or engaging the parking brake.
- The passenger's sudden and uncoordinated attempt to exit the aircraft, likely driven by distress from motion sickness, led to the accidental movement of the throttle.
- The aircraft sustained significant damage to the propeller and wing surfaces, and the airfield fence was also damaged.
- The pilot sustained a broken nose and various contusions due to the fall from the wing, while the passenger remained uninjured.