Event Details
While in cruise flight at an altitude of 2,500 feet, the pilot reported feeling a "thump" and subsequently observed black smoke or soot on the outer third of the aileron. In response, the pilot executed an emergency descent and landed at a private airport without further incident.
Examination Findings
Post-landing inspection of the right wing revealed extensive fire damage concentrated in the center of the wing. The damage included ballooning of the wing skin and soot trailing over the right aileron. Despite a thorough examination, investigators were unable to determine the source of fuel or fuel vapor, or the ignition source that initiated the fire, due to the extent of the fire damage.