Incident Summary
A pilot reported smoke in the cockpit, which he stated originated from underneath the instrument panel. During the event, the trim tab switch became inoperative, the flight controls became "heavy," and the weather radar circuit breaker popped even though the radar was off. The pilot stated that the smoke eventually stopped, and he continued to the destination and landed without incident.
Examination Findings
Examination of the aircraft revealed that inside the right wing, near the root section, the wires for the navigation light, strobe light, and fuel quantity transmitter had shorted and burned. These wires were located next to a fuel vent line that had been changed.
Maintenance History
Review of maintenance records disclosed that approximately three years ago, a radar pod and radome were installed. This installation involved routing wires through the area where the shorted wires were located.