Incident Description
While cruising at 5,000 feet, the pilot detected an odor of electrical fumes and observed smoke emanating from the flap indicator gauge. He pulled the wing flap circuit breaker, but shortly thereafter, thick smoke emerged from under the instrument panel, and flames were visible behind it.
Response
The pilot attempted to extinguish the fire using a dry chemical fire extinguisher, which proved ineffective. He subsequently diverted the aircraft to Asheboro. Upon landing, the flames ceased.
Damage and Investigation
Fire damage was confined to the flap indicator gauge. However, heat damage prevented investigators from determining the specific cause of an internal electrical short. The flap indicator had been modified 216 flight hours prior to the incident, but the modification did not involve the wiring. It was noted that the flap indicator is protected by the starter circuit breaker; this information is included in wiring diagrams but not in the descriptions of the flap or electrical systems.