What happened
On August 14, 2018, a Cessna 210L with registration TG-KOY was conducting a flight from an unspecified location toward Fray Bartolomé de las Casas, Alta Verapaz, Guatemala. The flight was intended to transport two passengers, though the pilot was scheduled to return alone. During the flight, the pilot attempted to manipulate the magneto selector switch. During this action, the key—which reportedly had a pre-existing fissure—fractured at its base. This mechanical failure left the switch stuck in the 'OFF' position, resulting in a total engine shutdown. The pilot subsequently performed an emergency landing on a roadway near Aldea Campur.
The investigation
The DGAC/UIA investigation examined the aircraft's maintenance records, the pilot's flight history, and the physical wreckage. Investigators found that the aircraft's maintenance was up to date and that the airworthiness of the Cessna 210L was intact prior to the event. The investigation focused on the mechanical failure of the ignition switch and the pilot's decision-making process. While the aircraft suffered substantial damage due to the impact with the ground, the pilot emerged from the wreckage uninjured.
Findings
- The primary cause of the engine shutdown was the pilot's decision to manipulate the magneto selector switch while in flight, which caused the fractured key to leave the switch in the 'OFF' position.
- A pre-existing fissure in the ignition key contributed to its breakage during the manipulation.
- The pilot had flown over 100 hours in the month preceding the accident, which was identified as a potential contributing factor due to the possibility of fatigue or stress affecting concentration and decision-making.
- The aircraft was properly maintained and the weather conditions were favorable for visual flight.