Narrative:

While at cruise about 2 hours into flight; flight attendant calls saying he smelled something burning. We asked if there was smoke and if he could locate it and to move the passengers from the area and search for the source. He came back on saying he could not locate the smell; but it was getting stronger and that we had to get the aircraft on the ground. At that point I declared an emergency and landed at the closest suitable airport. The smell seemed to lessen but did not go away as passengers reported still smelling it as we landed. A slightly overweight landing at 145;500 was made at a rate of decent of around 250 FPM. We stopped on the ramp and firemen came on with heat seeking equipment and could find nothing hot. We proceeded to a gate and unloaded the passengers and maintenance came on and inspected the aircraft and could not find anything but a burned out reading light. Maintenance released the aircraft and we continued to our destiantion. I do not know what the burning smell was. I think a passenger may have had some device; but that is just a guess on my part. I do know that the flight attendants wanted the airplane on the ground as soon as possible. They are my eyes and ears in the cabin and had to trust their judgment. They both have been here over 20 years so they have experienced a lot and were concerned enough about it to request that we land. I have no suggestions on avoiding this happening again. We all performed as we are trained to do in this situation. The ending was that everyone was safe. Could we have continued? As it turned out; maybe; but that is after the fact. If it happened again I would do the exact same thing.

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Original NASA ASRS Text

Title: An A320 diverted to a nearby airport after a flight attendant reported a strong burning smell in the cabin. An emergency was declared and neither the fire crew nor maintenance could find the odor's source once on the ground.

Narrative: While at cruise about 2 hours into flight; Flight Attendant calls saying he smelled something burning. We asked if there was smoke and if he could locate it and to move the passengers from the area and search for the source. He came back on saying he could not locate the smell; but it was getting stronger and that we had to get the aircraft on the ground. At that point I declared an emergency and landed at the closest suitable airport. The smell seemed to lessen but did not go away as passengers reported still smelling it as we landed. A slightly overweight landing at 145;500 was made at a rate of decent of around 250 FPM. We stopped on the ramp and firemen came on with heat seeking equipment and could find nothing hot. We proceeded to a gate and unloaded the passengers and maintenance came on and inspected the aircraft and could not find anything but a burned out reading light. Maintenance released the aircraft and we continued to our destiantion. I do not know what the burning smell was. I think a passenger may have had some device; but that is just a guess on my part. I do know that the flight attendants wanted the airplane on the ground as soon as possible. They are my eyes and ears in the cabin and had to trust their judgment. They both have been here over 20 years so they have experienced a lot and were concerned enough about it to request that we land. I have no suggestions on avoiding this happening again. We all performed as we are trained to do in this situation. The ending was that everyone was safe. Could we have continued? As it turned out; maybe; but that is after the fact. If it happened again I would do the exact same thing.

Data retrieved from NASA's ASRS site as of April 2012 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.