Narrative:

On climb out of stl, at approximately 5000 ft MSL, electric smoke indication on cap. I was flying, captain ran checklist. Captain then took aircraft and had me re-do checklist. Upon completion of checklist, I declared an emergency with ATC, requesting return to stl. I then notified flight attendants of situation, made an announcement to passenger, and contacted flight control. As we descended through approximately 3000 ft electrical smoke light went out. On short final lowered gear by re-engaging acw generators. Landed without incident. Returned to gate without evacing passenger, as light out and no smoke in cabin. Maintenance notified of problem. Upon completion of their tests, problem did not recur so aircraft was returned on line.

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Original NASA ASRS Text

Title: AN MDT COMMERCIAL FIXED WING ACFT DECLARED AN EMER AND DIVERTED DUE TO A SMOKE DETECTOR WARNING.

Narrative: ON CLBOUT OF STL, AT APPROX 5000 FT MSL, ELECTRIC SMOKE INDICATION ON CAP. I WAS FLYING, CAPT RAN CHKLIST. CAPT THEN TOOK ACFT AND HAD ME RE-DO CHKLIST. UPON COMPLETION OF CHKLIST, I DECLARED AN EMER WITH ATC, REQUESTING RETURN TO STL. I THEN NOTIFIED FLT ATTENDANTS OF SIT, MADE AN ANNOUNCEMENT TO PAX, AND CONTACTED FLT CTL. AS WE DSNDED THROUGH APPROX 3000 FT ELECTRICAL SMOKE LIGHT WENT OUT. ON SHORT FINAL LOWERED GEAR BY RE-ENGAGING ACW GENERATORS. LANDED WITHOUT INCIDENT. RETURNED TO GATE WITHOUT EVACING PAX, AS LIGHT OUT AND NO SMOKE IN CABIN. MAINT NOTIFIED OF PROB. UPON COMPLETION OF THEIR TESTS, PROB DID NOT RECUR SO ACFT WAS RETURNED ON LINE.

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.