Narrative:

Just leveled at 9000 ft when I noticed smoke coming from the center avionics rack. There appeared to be an electrical short, smoke, and possibly fire in the avionics annunciator panel. I cancelled IFR and advised cmi approach that I was making a precautionary descent into dec, as I had smoke in the cabin. I also advised that I would be removing electrical power from the aircraft and would they call dec tower and tell them I'm coming. I used a portable handheld communication unit with an emergency antenna on the aircraft underside to communicate to dec tower. I told them that I would not require emergency equipment, however their fire truck was standing by. After landing I found the radio communication and selector panel had shorted in the MB test and lighting circuiting. The unit was removed and the flight continued to the original destination. The handheld radio with the emergency antenna was installed just for this kind of occurrence. It worked very well. However, I had no smoke goggles, no fire extinguisher and no protective breathing equipment on board. Had this situation become out of hand, I would have been unprepared to deal with it. You can bet my aircraft will have the right equipment next time.

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Original NASA ASRS Text

Title: PLT IN SMA ACFT EXPERIENCED SMOKE FROM ELECTRICAL IN COCKPIT. LANDED NEAREST SUITABLE.

Narrative: JUST LEVELED AT 9000 FT WHEN I NOTICED SMOKE COMING FROM THE CENTER AVIONICS RACK. THERE APPEARED TO BE AN ELECTRICAL SHORT, SMOKE, AND POSSIBLY FIRE IN THE AVIONICS ANNUNCIATOR PANEL. I CANCELLED IFR AND ADVISED CMI APCH THAT I WAS MAKING A PRECAUTIONARY DSCNT INTO DEC, AS I HAD SMOKE IN THE CABIN. I ALSO ADVISED THAT I WOULD BE REMOVING ELECTRICAL PWR FROM THE ACFT AND WOULD THEY CALL DEC TWR AND TELL THEM I'M COMING. I USED A PORTABLE HANDHELD COM UNIT WITH AN EMER ANTENNA ON THE ACFT UNDERSIDE TO COMMUNICATE TO DEC TWR. I TOLD THEM THAT I WOULD NOT REQUIRE EMER EQUIP, HOWEVER THEIR FIRE TRUCK WAS STANDING BY. AFTER LNDG I FOUND THE RADIO COM AND SELECTOR PANEL HAD SHORTED IN THE MB TEST AND LIGHTING CIRCUITING. THE UNIT WAS REMOVED AND THE FLT CONTINUED TO THE ORIGINAL DEST. THE HANDHELD RADIO WITH THE EMER ANTENNA WAS INSTALLED JUST FOR THIS KIND OF OCCURRENCE. IT WORKED VERY WELL. HOWEVER, I HAD NO SMOKE GOGGLES, NO FIRE EXTINGUISHER AND NO PROTECTIVE BREATHING EQUIP ON BOARD. HAD THIS SITUATION BECOME OUT OF HAND, I WOULD HAVE BEEN UNPREPARED TO DEAL WITH IT. YOU CAN BET MY ACFT WILL HAVE THE RIGHT EQUIP NEXT TIME.

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.