Narrative:

We were on the gep 4 arrival approximately 40 mi from the smp airport which was our destination. The 'avionic smoke' annunciator illuminated. Although there was no sight or smell of smoke, we completed the memory items and QRH checklist. We also contacted the flight attendant to make sure that he did not see or smell smoke. The flight attendant confirmed that there was no sight or smell of smoke. We contacted our maintenance department and dispatch and decided ti was best to declare an emergency with ATC. The first officer made an uneventful landing in msp. The arff (crash fire rescue equipment) inspected the aircraft upon landing and did not see any signs of smoke or fire. As we were taxiing into the gate the 'avionic smoke' light extinguished. I believe it was a faulty indication of avionic smoke.

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Original NASA ASRS Text

Title: AN SF340 FLT CREW DECLARES AN EMER 40 NM FROM DEST ARPT AFTER NOTING AN AVIONICS SMOKE WARNING ON THEIR ANNUNCIATOR, LANDS WITH CFR EQUIP IN ATTENDANCE AT MSP, MN.

Narrative: WE WERE ON THE GEP 4 ARR APPROX 40 MI FROM THE SMP ARPT WHICH WAS OUR DEST. THE 'AVIONIC SMOKE' ANNUNCIATOR ILLUMINATED. ALTHOUGH THERE WAS NO SIGHT OR SMELL OF SMOKE, WE COMPLETED THE MEMORY ITEMS AND QRH CHKLIST. WE ALSO CONTACTED THE FLT ATTENDANT TO MAKE SURE THAT HE DID NOT SEE OR SMELL SMOKE. THE FLT ATTENDANT CONFIRMED THAT THERE WAS NO SIGHT OR SMELL OF SMOKE. WE CONTACTED OUR MAINT DEPARTMENT AND DISPATCH AND DECIDED TI WAS BEST TO DECLARE AN EMER WITH ATC. THE FO MADE AN UNEVENTFUL LNDG IN MSP. THE ARFF (CFR) INSPECTED THE ACFT UPON LNDG AND DID NOT SEE ANY SIGNS OF SMOKE OR FIRE. AS WE WERE TAXIING INTO THE GATE THE 'AVIONIC SMOKE' LIGHT EXTINGUISHED. I BELIEVE IT WAS A FAULTY INDICATION OF AVIONIC SMOKE.

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.