Narrative:

On takeoff, smoke appeared in aft portion of main cabin. Flight attendant #2 called me to report it, and the first officer said it had been written up on the last flight (on the inbound leg) and that it should dissipate in about 1 min. It never did. It was a thick gray haze, there was a smell with it. The crew told us they would try a couple of different things to get rid of it, but nothing worked. The captain declared an emergency and we returned to mia. I relayed the emergency information to the rest of our crew, and we began to secure the cabin for landing. The captain made a PA, and we prepared the passenger for a regular landing. We landed and taxied to a gate, where the fire department boarded the aircraft. No one was hurt, crew or passenger. There was never an obvious cause, but it was mentioned that the APU may have leaked oil into an air-conditioning pack and that the heat from the engine caused it to heat up and smoke.

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Original NASA ASRS Text

Title: FLT ATTENDANT RPT, DC9-80, MIA-BOS, SMOKE AND FUMES IN CABIN. RETURN TO MIAMI.

Narrative: ON TKOF, SMOKE APPEARED IN AFT PORTION OF MAIN CABIN. FLT ATTENDANT #2 CALLED ME TO RPT IT, AND THE FO SAID IT HAD BEEN WRITTEN UP ON THE LAST FLT (ON THE INBOUND LEG) AND THAT IT SHOULD DISSIPATE IN ABOUT 1 MIN. IT NEVER DID. IT WAS A THICK GRAY HAZE, THERE WAS A SMELL WITH IT. THE CREW TOLD US THEY WOULD TRY A COUPLE OF DIFFERENT THINGS TO GET RID OF IT, BUT NOTHING WORKED. THE CAPT DECLARED AN EMER AND WE RETURNED TO MIA. I RELAYED THE EMER INFO TO THE REST OF OUR CREW, AND WE BEGAN TO SECURE THE CABIN FOR LNDG. THE CAPT MADE A PA, AND WE PREPARED THE PAX FOR A REGULAR LNDG. WE LANDED AND TAXIED TO A GATE, WHERE THE FIRE DEPT BOARDED THE ACFT. NO ONE WAS HURT, CREW OR PAX. THERE WAS NEVER AN OBVIOUS CAUSE, BUT IT WAS MENTIONED THAT THE APU MAY HAVE LEAKED OIL INTO AN AIR-CONDITIONING PACK AND THAT THE HEAT FROM THE ENG CAUSED IT TO HEAT UP AND SMOKE.

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.