What happened
On January 6, 2022, at approximately 15:00 local time, a Sonaca S201, registration HB-KGF, was conducting a private flight under Visual Flight Rules (VFR) at Locarno Airport (LSZL). The aircraft departed from and was intended to return to the same airfield. During the flight, the pilot observed the development of smoke within the engine compartment, which subsequently spread into the aircraft cabin.
In response to the smoke, the pilot executed an emergency landing at Locarno Airport. There were no fatalities and no injuries reported following the incident.
The investigation
The Swiss Transportation Safety Investigation Board (SUST) opened an inquiry into the occurrence to determine the origin of the smoke. The preliminary investigation focused on the mechanical conditions of the engine compartment and the cabin environment at the time of the event.