Narrative:

Approximately 5 minutes after level off at FL370; noticed smoke emanating from the area behind the captain's chair. Initiated immediate descent; donned oxygen mask; informed ATC of problem and requested lower altitude.passing FL250 during descent; the smoke abated. Continued descent to 12000 ft and proceeded to ZZZ for landing.

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Original NASA ASRS Text

Title: Falcon 900 Captain reported smoke in the cockpit emanating from the area behind the Captain's seat. A descent was initiated and the smoke began to dissipate on descent.

Narrative: Approximately 5 minutes after level off at FL370; noticed smoke emanating from the area behind the Captain's chair. Initiated immediate descent; donned oxygen mask; informed ATC of problem and requested lower altitude.Passing FL250 during descent; the smoke abated. Continued descent to 12000 ft and proceeded to ZZZ for landing.

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.