During taxi for takeoff an SF340's FMC began smoking so the crew alerted airport rescue and fire fig...

Attributes
ACN	923701
Time
Date	201012
Local Time Of Day	1201-1800
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Light	Daylight
Aircraft 1
Make Model Name	Saab 340 Undifferentiated
Operating Under FAR Part	Part 121
Flight Phase	Taxi
Flight Plan	IFR
Component
Aircraft Component	FMS/FMC
Person 1
Function	Captain
Qualification	Flight Crew Air Transport Pilot (ATP)
Experience	Flight Crew Last 90 Days 12 Flight Crew Total 9500 Flight Crew Type 8000
Events
Anomaly	Flight Deck / Cabin / Aircraft Event Smoke / Fire / Fumes / Odor

Narrative:

As we were taxing north to taxiway uniform the first officer started the before takeoff checklist. During this time the first officer noticed smoke coming from the area of the FMS. We called ground control and reported avionics smoke in the flight deck and requested airport rescue and fire fighting. I than set the parking brake and we performed the action card/non-normal checklist for avionics smoke. We pulled the 'area nav' circuit breaker and turned off the left and right avionics switches. This stopped the smoke. After assessing the situation we taxied back to the gate with airport rescue and fire fighting following us while ventilating the flight deck as per the non-normal procedures. We deplaned normally.

Original NASA ASRS Text

Title: During taxi for takeoff an SF340's FMC began smoking so the crew alerted Airport Rescue and Fire Fighting; turned avionics equipment off to successfully stop the smoke and returned to the gate.

Narrative: As we were taxing north to Taxiway Uniform the First Officer started the before takeoff checklist. During this time the First Officer noticed smoke coming from the area of the FMS. We called Ground Control and reported avionics smoke in the flight deck and requested Airport Rescue and Fire Fighting. I than set the parking brake and we performed the action card/non-normal checklist for avionics smoke. We pulled the 'Area Nav' circuit breaker and turned off the left and right avionics switches. This stopped the smoke. After assessing the situation we taxied back to the gate with Airport Rescue and Fire Fighting following us while ventilating the flight deck as per the non-normal procedures. We deplaned normally.

Data retrieved from NASA's ASRS site as of April 2012 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.

During taxi for takeoff an SF340's FMC began smoking so the crew alerted airport rescue and fire fighting; turned avionics equipment off to successfully stop the smoke and returned to the gate.