Narrative:

Started smelling smoke in the cockpit. Donned oxygen masks; contacted ATC; declared an emergency and asked for a return to ZZZ. Ran the qrc for smoke. The smoke began dissipating. Gave cabin advisory to flight attendants. Landed without event at ZZZ. Emergency vehicles followed us to gate per our request. Offloaded the passenger through the jetway. At last contact; the mechanics were thinking the cause of the smoke was a blower fan.

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Original NASA ASRS Text

Title: COCKPIT SMOKE WAS ENCOUNTERED BY AN A320 FLT CREW. EMER WAS DECLARED AND FLT DIVERTED TO THE DEP ARPT FOR AN UNEVENTFUL LNDG.

Narrative: STARTED SMELLING SMOKE IN THE COCKPIT. DONNED OXYGEN MASKS; CONTACTED ATC; DECLARED AN EMER AND ASKED FOR A RETURN TO ZZZ. RAN THE QRC FOR SMOKE. THE SMOKE BEGAN DISSIPATING. GAVE CABIN ADVISORY TO FLT ATTENDANTS. LANDED WITHOUT EVENT AT ZZZ. EMER VEHICLES FOLLOWED US TO GATE PER OUR REQUEST. OFFLOADED THE PAX THROUGH THE JETWAY. AT LAST CONTACT; THE MECHS WERE THINKING THE CAUSE OF THE SMOKE WAS A BLOWER FAN.

Data retrieved from NASA's ASRS site as of May 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.