Narrative:

The aircraft radios were inspected and replaced at the owner's request. A training flight was undertaken from rdu to tdf and return. Upon arriving at tdf I noticed smoke coming from the instrument panel. At that time I shut off all electrical equipment and landed. After waiting approximately 20 mins, we departed tdf for rdu, VFR, testing the equipment individually to determine what was causing the problem. At the 10 mi mark north of rdu, the smoke returned. I advised ATC that 'I had smoke in the cockpit and would like to shut the radios and electrical off.' I was offered priority handling, but refused it. No emergency was declared. I was given traffic to follow to the runway (with the runway in sight, runway 23R). I was cleared to land and told to look for light signals. I landed as instructed and was met by emergency equipment. After taxiing to the ramp, I was met by an FAA inspector and gave him the above information along with my certificates. He wanted to inspect the aircraft logs to see a sign-off for the radio work. The logs had not been signed and neither had a work order been prepared. The inspector advised, that if work was done to the radios and not been documented, that I had flown an unairworthy aircraft. He was going to pass the information on in a report.

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Original NASA ASRS Text

Title: INSTRUCTOR AND STUDENT EXPERIENCE COCKPIT ELECTRICAL SMOKE, APPARENTLY FROM NEWLY SERVICED RADIOS.

Narrative: THE ACFT RADIOS WERE INSPECTED AND REPLACED AT THE OWNER'S REQUEST. A TRNING FLT WAS UNDERTAKEN FROM RDU TO TDF AND RETURN. UPON ARRIVING AT TDF I NOTICED SMOKE COMING FROM THE INSTRUMENT PANEL. AT THAT TIME I SHUT OFF ALL ELECTRICAL EQUIP AND LANDED. AFTER WAITING APPROX 20 MINS, WE DEPARTED TDF FOR RDU, VFR, TESTING THE EQUIP INDIVIDUALLY TO DETERMINE WHAT WAS CAUSING THE PROB. AT THE 10 MI MARK N OF RDU, THE SMOKE RETURNED. I ADVISED ATC THAT 'I HAD SMOKE IN THE COCKPIT AND WOULD LIKE TO SHUT THE RADIOS AND ELECTRICAL OFF.' I WAS OFFERED PRIORITY HANDLING, BUT REFUSED IT. NO EMER WAS DECLARED. I WAS GIVEN TFC TO FOLLOW TO THE RWY (WITH THE RWY IN SIGHT, RWY 23R). I WAS CLRED TO LAND AND TOLD TO LOOK FOR LIGHT SIGNALS. I LANDED AS INSTRUCTED AND WAS MET BY EMER EQUIP. AFTER TAXIING TO THE RAMP, I WAS MET BY AN FAA INSPECTOR AND GAVE HIM THE ABOVE INFO ALONG WITH MY CERTIFICATES. HE WANTED TO INSPECT THE ACFT LOGS TO SEE A SIGN-OFF FOR THE RADIO WORK. THE LOGS HAD NOT BEEN SIGNED AND NEITHER HAD A WORK ORDER BEEN PREPARED. THE INSPECTOR ADVISED, THAT IF WORK WAS DONE TO THE RADIOS AND NOT BEEN DOCUMENTED, THAT I HAD FLOWN AN UNAIRWORTHY ACFT. HE WAS GOING TO PASS THE INFO ON IN A RPT.

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.