Narrative:

Pilot and front seat passenger smelled and shortly after saw smoke emanating from the instrument panel. I turned off the #2 navigation/communication and found that the smoke ceased. I then pulled the circuit breaker and opened the vent window to air out the cabin. I advised ATC of the problem and requested and received clearance to the departure airport. I asked the front seat passenger to advise the rest of the occupants of the situation, to remain calm, and asked him to retrieve my approach charts. This led to an uneventful landing. I contacted the tower and was told no report was required to be filed. I have learned to keep handy, the plate for the approach in use at the departure airport in the event I ever have to return for landing during IFR conditions.

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Original NASA ASRS Text

Title: A FAULTED CIRCUIT CTLING AN SMA'S #2 COM RADIO PRODUCED SMOKE IN THE COCKPIT. THE SYS WAS TURNED OFF, SMOKE ABATED AND A RETURN AND LAND WAS MADE AT ACK, MA.

Narrative: PLT AND FRONT SEAT PAX SMELLED AND SHORTLY AFTER SAW SMOKE EMANATING FROM THE INST PANEL. I TURNED OFF THE #2 NAV/COM AND FOUND THAT THE SMOKE CEASED. I THEN PULLED THE CIRCUIT BREAKER AND OPENED THE VENT WINDOW TO AIR OUT THE CABIN. I ADVISED ATC OF THE PROB AND REQUESTED AND RECEIVED CLRNC TO THE DEP ARPT. I ASKED THE FRONT SEAT PAX TO ADVISE THE REST OF THE OCCUPANTS OF THE SIT, TO REMAIN CALM, AND ASKED HIM TO RETRIEVE MY APCH CHARTS. THIS LED TO AN UNEVENTFUL LNDG. I CONTACTED THE TWR AND WAS TOLD NO RPT WAS REQUIRED TO BE FILED. I HAVE LEARNED TO KEEP HANDY, THE PLATE FOR THE APCH IN USE AT THE DEP ARPT IN THE EVENT I EVER HAVE TO RETURN FOR LNDG DURING IFR CONDITIONS.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.