What happened
Following maintenance performed on the engine turbochargers and exhaust systems several days prior to the flight, the pilot departed and subsequently reported that the left engine lost power. In response to the power loss, the pilot elected to return to the airport.
A witness observed the aircraft heading toward the airport with an orange glow visible under the left wing, approximately four feet outboard of the fuselage. The witness then heard a loud pop, after which the left wing separated from the airplane, causing the aircraft to fall to the ground.
The investigation
Post-accident inspection revealed extensive fire damage located in the area of the left wheel well and spar. This damage was situated behind the firewall, immediately aft of the turbocharger exhaust. During the examination, it was found that fuel lines in the wheel well area had burned away. Additionally, the left engine turbocharger tail pipe and the Marmon connector clamp were missing from the aircraft. The engines involved were equipped with AiResearch turbochargers under STC SA909WE.