Event Overview
The airplane was conducting an aerial pipeline observation flight when an in-flight fire occurred. The pilot stated that he conducted a thorough preflight examination of the aircraft, including fuel samples from each tank, and reported no fuel, oil, or other discrepancies. Approximately 1 hour and 20 minutes into the flight, the pilot smelled wisps of smoke. The smell became stronger, forcing him to search for its source. He then felt heat on his left shin and detected smoke emitting from beneath the left side of the instrument panel. Opening the door to release smoke from the cabin, the pilot noticed a small flame coming from the electrical wiring bundle. He used the fire extinguisher to douse the flame, and the engine continued to run normally at that time.
Fire Progression and Emergency Landing
The pilot initially turned toward the closest airport, approximately nine miles from his position. However, a large, black cloud of smoke then filled the cockpit. Deciding to land as soon as possible, the pilot placed his head outside the pilot's side door window to navigate and breathe. While doing so, he observed a flame emitting from the right side of the engine cowl. The pilot executed a forced landing with the landing gear retracted in a field.
Post-Landing and Examination
After landing, the pilot evacuated the airplane before the fire engulfed three-fourths of the fuselage. An on-scene examination was performed. Flight control continuity was established from the surfaces to the cabin area. Testing of systems was unable to be performed due to the extent of fire damage.