Narrative:

We were at cruise; when we noticed the smell of smoke. The engineer opened the door to the courier/lavatory section of the aircraft. I xferred control of the aircraft to the first officer and went to investigate. Smoke was pouring out of the bottom of the lavatory. There was the loud sound of a motor grinding. We believed that it was the lavatory motor. I instructed the first officer to declare an emergency and head for the nearest suitable airport. I instructed the flight engineer to find and pull the lavatory circuit breaker. I got the fire ax and the fire extinguisher and attempted to get into the lavatory compartment. The ax bounced off the steel compartment cover. I finally got the zeuss fasteners opened with a dime. I deployed the extinguisher and the smoke and noise stopped. Upon returning to the cockpit; the first officer was in a descent for ZZZ. The rest of the flight was uneventful. Arff was standing by and met the aircraft upon parking. It was later determined that the recirculation fan motor was the culprit. It is located under the lavatory.

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Original NASA ASRS Text

Title: SMOKE WAS DISCOVERED COMING FROM THE LAVATORY AREA OF A HEAVY FREIGHT ACFT. EMER WAS DECLARED; AND THE FLT DIVERTED; EXTINGUISHING THE SOURCE OF THE SMOKE IN THE DESCENT.

Narrative: WE WERE AT CRUISE; WHEN WE NOTICED THE SMELL OF SMOKE. THE ENGINEER OPENED THE DOOR TO THE COURIER/LAVATORY SECTION OF THE ACFT. I XFERRED CTL OF THE ACFT TO THE FO AND WENT TO INVESTIGATE. SMOKE WAS POURING OUT OF THE BOTTOM OF THE LAVATORY. THERE WAS THE LOUD SOUND OF A MOTOR GRINDING. WE BELIEVED THAT IT WAS THE LAVATORY MOTOR. I INSTRUCTED THE FO TO DECLARE AN EMER AND HEAD FOR THE NEAREST SUITABLE ARPT. I INSTRUCTED THE FE TO FIND AND PULL THE LAVATORY CIRCUIT BREAKER. I GOT THE FIRE AX AND THE FIRE EXTINGUISHER AND ATTEMPTED TO GET INTO THE LAVATORY COMPARTMENT. THE AX BOUNCED OFF THE STEEL COMPARTMENT COVER. I FINALLY GOT THE ZEUSS FASTENERS OPENED WITH A DIME. I DEPLOYED THE EXTINGUISHER AND THE SMOKE AND NOISE STOPPED. UPON RETURNING TO THE COCKPIT; THE FO WAS IN A DSCNT FOR ZZZ. THE REST OF THE FLT WAS UNEVENTFUL. ARFF WAS STANDING BY AND MET THE ACFT UPON PARKING. IT WAS LATER DETERMINED THAT THE RECIRCULATION FAN MOTOR WAS THE CULPRIT. IT IS LOCATED UNDER THE LAVATORY.

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.