Narrative:

Shortly after takeoff; a burning smell in all cabins of aircraft. I elected to return. Aircraft was landed overweight at 137;000 pounds. I declared an emergency with ATC due to smell and overweight landing. Landing normal. Smell was due to heavy pine pollen ingested into aircraft pack system.

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Original NASA ASRS Text

Title: MD80 Captain reports burning smell in the cabin shortly after takeoff. An emergency is declared and flight returns to departure airport for an overweight landing. Pine tree pollen is believed to be the cause of the smell.

Narrative: Shortly after takeoff; a burning smell in all cabins of aircraft. I elected to return. Aircraft was landed overweight at 137;000 LBS. I declared an emergency with ATC due to smell and overweight landing. Landing normal. Smell was due to heavy pine pollen ingested into aircraft pack system.

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.