Narrative:

While descending through about 18;000 feet into [destination] both the captain and I noticed a burning smell in the cockpit. We thought the smell was similar to paper or cigarettes burning and thought that a passenger might have smoked in the lav. I immediately contacted the lead flight attendant and asked if she too smelled a strange smell and if she would look into the bathrooms and see if she could identify the source of the smell. She said that she smelled the odor and would investigate and get back to us. We accomplished the smoke; fumes; odor non-normal checklist and attempted to identify any systems that may have malfunctioned and caused the smoky smell. We did not see any abnormalities and did not have any indications of problems other than a status message which appeared shortly thereafter L2 air compressor. Per the checklist we shut off the recirculation fans and power outlets and the smell diminished. The lead flight attendant called back with a report that the fumes had been perceived throughout the cabin and that they were diminishing but that some passengers were concerned and asked that we make an announcement. The captain also had one of the deadheading pilots in the cabin give him a report over the interphone which echoed what the lead flight attendant told us. The captain then assigned the flying and ATC duties to me so that he could address the passengers and tell them that we were working on the problem and that we would be landing very soon. At this point we were very close to the airport and were vectored to intercept final. After intercepting the localizer and starting to descend on the approach we thought that the smell increased again so the captain [advised ATC] and asked for the emergency vehicles to meet us at the gate to check for any visible smoke outside the aircraft. We had just enough time to brief the lead flight attendant before landing that the emergency vehicles would be meeting us. After an uneventful landing we taxied to the gate and I briefed the passengers that we had requested emergency vehicles as a precaution only and that we did not show any abnormalities. The fire and rescue personnel checked out the exterior of the plane and did not find any indication of smoke or flames so the captain canceled the emergency and the passengers deplaned.

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Original NASA ASRS Text

Title: B787 First Officer reported noticing a smoky smell in the aircraft about the same time they received a status message for the L2 air compressor.

Narrative: While descending through about 18;000 feet into [destination] both the Captain and I noticed a burning smell in the cockpit. We thought the smell was similar to paper or cigarettes burning and thought that a passenger might have smoked in the lav. I immediately contacted the lead flight attendant and asked if she too smelled a strange smell and if she would look into the bathrooms and see if she could identify the source of the smell. She said that she smelled the odor and would investigate and get back to us. We accomplished the smoke; fumes; odor non-normal checklist and attempted to identify any systems that may have malfunctioned and caused the smoky smell. We did not see any abnormalities and did not have any indications of problems other than a status message which appeared shortly thereafter L2 air compressor. Per the checklist we shut off the recirculation fans and power outlets and the smell diminished. The lead flight attendant called back with a report that the fumes had been perceived throughout the cabin and that they were diminishing but that some passengers were concerned and asked that we make an announcement. The Captain also had one of the deadheading pilots in the cabin give him a report over the interphone which echoed what the lead flight attendant told us. The Captain then assigned the flying and ATC duties to me so that he could address the passengers and tell them that we were working on the problem and that we would be landing very soon. At this point we were very close to the airport and were vectored to intercept final. After intercepting the localizer and starting to descend on the approach we thought that the smell increased again so the Captain [advised ATC] and asked for the emergency vehicles to meet us at the gate to check for any visible smoke outside the aircraft. We had just enough time to brief the lead flight attendant before landing that the emergency vehicles would be meeting us. After an uneventful landing we taxied to the gate and I briefed the passengers that we had requested emergency vehicles as a precaution only and that we did not show any abnormalities. The fire and rescue personnel checked out the exterior of the plane and did not find any indication of smoke or flames so the Captain canceled the emergency and the passengers deplaned.

Data retrieved from NASA's ASRS site 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.