Narrative:

After takeoff from runway xxr at airport ZZZ smoke began to fill the cockpit at approximately 2;000 feet. Requested to level off at 3;000 feet then [advised ATC] and requested a return to airport. Turned off left recirculation fan as this seemed to be source of the smoke; smoke then cleared rapidly. Landed uneventfully on runway xxl and returned to the gate where maintenance began a check for source of the smoke and overweight landing.

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Original NASA ASRS Text

Title: A B-737-800 flight crew noted dark grey smoke in the cockpit after takeoff at about 2;000 feet. They requested level off at 3;000 feet; and requested return to departure airport. They turned off the left recirculation fan and the smoke stopped. They landed uneventfully at 1;000 pounds over max landing weight.

Narrative: After takeoff from runway XXR at Airport ZZZ Smoke began to fill the cockpit at approximately 2;000 feet. Requested to level off at 3;000 feet then [advised ATC] and requested a return to Airport. Turned off Left recirculation fan as this seemed to be source of the smoke; smoke then cleared rapidly. Landed uneventfully on runway XXL and returned to the gate where maintenance began a check for source of the smoke and overweight 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.