Narrative:

Upon review of the log history during pre-flight planning; it was evident that the aircraft had numerous write ups regarding a suspect loud pressure leak at door 1L or possible duct leak. Maintenance had been performed each time indicating that the problem had been addressed properly. We departed and climbed to our cruise altitude of FL360 without incident. We queried the purser at this time and she said all was normal. Shortly thereafter (5-10 minutes); we got a call saying that the noise around 1L was back and both the captain and I investigated it. We both agreed that the noise was not normal; in fact it was loud enough to be heard in the cockpit with the door closed. The captain elected to divert and we obtained a clearance from ATC. We were about 90 miles from the diversion airport and had started our descent when the purser informed us of light smoke in the cabin and that they could not determine the source. The captain declared an emergency and ATC cleared us direct to the airport. The appropriate qrc was completed followed by a normal landing. Following an inspection by the fire marshal; the flight attendants informed us that the smoke had subsided and the captain taxied safely to the gate.

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Original NASA ASRS Text

Title: A B757-200 was diverting to an enroute airport for a suspected main cabin door seal leak when the Flight Attendants reported smoke in the cabin. An emergency was declared and the flight proceeded directly to the airport.

Narrative: Upon review of the log history during pre-flight planning; it was evident that the aircraft had numerous write ups regarding a suspect loud pressure leak at door 1L or possible duct leak. Maintenance had been performed each time indicating that the problem had been addressed properly. We departed and climbed to our cruise altitude of FL360 without incident. We queried the purser at this time and she said all was normal. Shortly thereafter (5-10 minutes); we got a call saying that the noise around 1L was back and both the Captain and I investigated it. We both agreed that the noise was not normal; in fact it was loud enough to be heard in the cockpit with the door closed. The Captain elected to divert and we obtained a clearance from ATC. We were about 90 miles from the diversion airport and had started our descent when the purser informed us of light smoke in the cabin and that they could not determine the source. The Captain declared an emergency and ATC cleared us direct to the airport. The appropriate QRC was completed followed by a normal landing. Following an inspection by the Fire Marshal; the Flight Attendants informed us that the smoke had subsided and the captain taxied safely to the gate.

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.