Narrative:

The first officer was the PF. After leveling at cruise FL260; flight attendant called the cockpit to report smoke in the aft cabin and both aft lavatory smoke detectors had activated. I asked if she could determine the source of the smoke. She could not. The first officer and I donned oxygen masks and I declared an emergency with center. Center cleared us direct to ZZZ; and we proceeded direct to the airport. The flight attendant stayed on the interphone with me while I proceeded with the emergency checklist. As I worked through the checklist; the flight attendant reported that the smoke was still present but the smoke detectors had stopped. A few mins later; she reported that the smoke seemed to be getting better. We continued to ZZZ and landed on runway. After stopping on the runway; the fire chief inspected the aircraft and could find no signs of smoke or fire. We decided to taxi to the gate. Because the fire crew had no heat detecting capabilities; they were unable to determine any fire/heat source that may have been in the cargo bins. As a precaution; I requested a fire truck follow us to the gate. We asked for and received priority handling to the gate. We arrived at the gate and deplaned the passenger without any further mishaps. It would have been of great help if the fire crew had the equipment to determine heat within the cargo bins of the aircraft. The source of the smoke/heat could not be determined by the crew and I felt a fire threat could very possibly still be present as we taxied. Supplemental information from acn 814345: mechanics were waiting upon our arrival. One stated that this aircraft had a prior 'history' of the same problem.

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Original NASA ASRS Text

Title: MD88 CABIN ATTENDANT INFORMS FLIGHT CREW OF SMOKE IN CABIN. CREW DECLARES EMERGENCY AND PROCEEDS DIRECTLY TO DESTINATION FOR LANDING. SMOKE DISSIPATES PRIOR TO LANDING.

Narrative: THE FO WAS THE PF. AFTER LEVELING AT CRUISE FL260; FLT ATTENDANT CALLED THE COCKPIT TO RPT SMOKE IN THE AFT CABIN AND BOTH AFT LAVATORY SMOKE DETECTORS HAD ACTIVATED. I ASKED IF SHE COULD DETERMINE THE SOURCE OF THE SMOKE. SHE COULD NOT. THE FO AND I DONNED OXYGEN MASKS AND I DECLARED AN EMER WITH CTR. CTR CLRED US DIRECT TO ZZZ; AND WE PROCEEDED DIRECT TO THE ARPT. THE FLT ATTENDANT STAYED ON THE INTERPHONE WITH ME WHILE I PROCEEDED WITH THE EMER CHKLIST. AS I WORKED THROUGH THE CHKLIST; THE FLT ATTENDANT RPTED THAT THE SMOKE WAS STILL PRESENT BUT THE SMOKE DETECTORS HAD STOPPED. A FEW MINS LATER; SHE RPTED THAT THE SMOKE SEEMED TO BE GETTING BETTER. WE CONTINUED TO ZZZ AND LANDED ON RWY. AFTER STOPPING ON THE RWY; THE FIRE CHIEF INSPECTED THE ACFT AND COULD FIND NO SIGNS OF SMOKE OR FIRE. WE DECIDED TO TAXI TO THE GATE. BECAUSE THE FIRE CREW HAD NO HEAT DETECTING CAPABILITIES; THEY WERE UNABLE TO DETERMINE ANY FIRE/HEAT SOURCE THAT MAY HAVE BEEN IN THE CARGO BINS. AS A PRECAUTION; I REQUESTED A FIRE TRUCK FOLLOW US TO THE GATE. WE ASKED FOR AND RECEIVED PRIORITY HANDLING TO THE GATE. WE ARRIVED AT THE GATE AND DEPLANED THE PAX WITHOUT ANY FURTHER MISHAPS. IT WOULD HAVE BEEN OF GREAT HELP IF THE FIRE CREW HAD THE EQUIP TO DETERMINE HEAT WITHIN THE CARGO BINS OF THE ACFT. THE SOURCE OF THE SMOKE/HEAT COULD NOT BE DETERMINED BY THE CREW AND I FELT A FIRE THREAT COULD VERY POSSIBLY STILL BE PRESENT AS WE TAXIED. SUPPLEMENTAL INFO FROM ACN 814345: MECHS WERE WAITING UPON OUR ARR. ONE STATED THAT THIS ACFT HAD A PRIOR 'HISTORY' OF THE SAME PROB.

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.