Narrative:

We were on the arrival inbound to ZZZ. We were on with approach approximately 20 NM southwest of the VOR. We received a master warning for avionics smoke. Both pilots looked behind my seat for any sign of smoke. Neither of us saw smoke or smelled any odor indicating a fire. I elected to call the flight attendant and asked him to check the area near the air stairs for any sign of smoke. He indicated that he did not see any smoke or smell an odor. I declared an emergency with approach. I explained that we had an avionics smoke warning; but did not have any indications of a fire. I requested that the fire trucks stand by and that; for the time being; we were not planning an evacuate/evacuation. I made a PA to the passenger explaining the situation. Next I completed the descent and approach checklists while the first officer continued the visual approach to ZZZ. Finally; I made a quick call to dispatch to give them a heads up of our situation. I would've liked to have called them earlier; but with all the other tasks to complete I felt I called them as soon as I could. The first officer landed without incident. We taxied clear of the runway and talked to crash fire rescue equipment to see if they saw anything abnormal from the outside. They said everything looked good. I asked to have a truck follow us to the gate just in case something happened. We parked at the gate a short time later and canceled the emergency. Supplemental information from acn 711867: we consulted the QRH; declared an emergency with ATC and requested crash fire rescue equipment. The warning ceased after 2-3 mins and did not return. We still continued as quickly as possible to the airport and I; as the PF; made visual approach and landed.

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Original NASA ASRS Text

Title: A CE750 AVIONICS SMOKE DETECTOR ALERTED FLT CREW WITHOUT VISUAL SMOKE PRESENT. AN EMER WAS DECLARED.

Narrative: WE WERE ON THE ARR INBOUND TO ZZZ. WE WERE ON WITH APCH APPROX 20 NM SW OF THE VOR. WE RECEIVED A MASTER WARNING FOR AVIONICS SMOKE. BOTH PLTS LOOKED BEHIND MY SEAT FOR ANY SIGN OF SMOKE. NEITHER OF US SAW SMOKE OR SMELLED ANY ODOR INDICATING A FIRE. I ELECTED TO CALL THE FLT ATTENDANT AND ASKED HIM TO CHK THE AREA NEAR THE AIR STAIRS FOR ANY SIGN OF SMOKE. HE INDICATED THAT HE DID NOT SEE ANY SMOKE OR SMELL AN ODOR. I DECLARED AN EMER WITH APCH. I EXPLAINED THAT WE HAD AN AVIONICS SMOKE WARNING; BUT DID NOT HAVE ANY INDICATIONS OF A FIRE. I REQUESTED THAT THE FIRE TRUCKS STAND BY AND THAT; FOR THE TIME BEING; WE WERE NOT PLANNING AN EVAC. I MADE A PA TO THE PAX EXPLAINING THE SIT. NEXT I COMPLETED THE DSCNT AND APCH CHKLISTS WHILE THE FO CONTINUED THE VISUAL APCH TO ZZZ. FINALLY; I MADE A QUICK CALL TO DISPATCH TO GIVE THEM A HEADS UP OF OUR SIT. I WOULD'VE LIKED TO HAVE CALLED THEM EARLIER; BUT WITH ALL THE OTHER TASKS TO COMPLETE I FELT I CALLED THEM AS SOON AS I COULD. THE FO LANDED WITHOUT INCIDENT. WE TAXIED CLR OF THE RWY AND TALKED TO CFR TO SEE IF THEY SAW ANYTHING ABNORMAL FROM THE OUTSIDE. THEY SAID EVERYTHING LOOKED GOOD. I ASKED TO HAVE A TRUCK FOLLOW US TO THE GATE JUST IN CASE SOMETHING HAPPENED. WE PARKED AT THE GATE A SHORT TIME LATER AND CANCELED THE EMER. SUPPLEMENTAL INFO FROM ACN 711867: WE CONSULTED THE QRH; DECLARED AN EMER WITH ATC AND REQUESTED CFR. THE WARNING CEASED AFTER 2-3 MINS AND DID NOT RETURN. WE STILL CONTINUED AS QUICKLY AS POSSIBLE TO THE ARPT AND I; AS THE PF; MADE VISUAL APCH AND LANDED.

Data retrieved from NASA's ASRS site as of January 2009 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.