Narrative:

Level at 9000 ft MSL. Fumes in the cockpit. Went on oxygen and ind departure control cleared us to fly direct to ind VOR and maintain 9000 ft. I was flying and turned south towards the VOR and started a descent to 4000 ft which I thought I heard in the clearance. My first officer corrected me. I stopped the descent at 8500 ft and quickly returned to 9000 ft. Returned as soon as possible to runway 23L at ind with oxygen and smoke goggles on. Uneventful landing and return to gate. Cause of smoke was burned up gasper fan.

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Original NASA ASRS Text

Title: A B727 ON INITIAL CLB AT 9000 FT DECLARED AN EMER AND DIVERTED DUE TO FUMES IN THE COCKPIT CAUSED BY A FAILED GASPER FAN.

Narrative: LEVEL AT 9000 FT MSL. FUMES IN THE COCKPIT. WENT ON OXYGEN AND IND DEP CTL CLRED US TO FLY DIRECT TO IND VOR AND MAINTAIN 9000 FT. I WAS FLYING AND TURNED S TOWARDS THE VOR AND STARTED A DSCNT TO 4000 FT WHICH I THOUGHT I HEARD IN THE CLRNC. MY FO CORRECTED ME. I STOPPED THE DSCNT AT 8500 FT AND QUICKLY RETURNED TO 9000 FT. RETURNED ASAP TO RWY 23L AT IND WITH OXYGEN AND SMOKE GOGGLES ON. UNEVENTFUL LNDG AND RETURN TO GATE. CAUSE OF SMOKE WAS BURNED UP GASPER FAN.

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.