Narrative:

[After takeoff] at approximately 100 ft AGL engine began to run noticeably rough; but maintained partial power. [I] immediately advised tower that [I] was landing with a rough running engine. [I] was cleared to land xxr. [Corporate jet] on final for xxr was advised to prepare for possible go-around. Was able to land xxr and clear under power without further incident. [Corporate jet] was advised runway was clear and landed without incident. [I] taxied under power to parking spot for further investigation. [I] called tower who advised that it was a non-reportable incident. Incident reaffirms wisdom of always briefing a departure emergency plan.

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Original NASA ASRS Text

Title: PA-12-150 pilot reported a rough running engine early in the climb and returned to land at the departure airport.

Narrative: [After takeoff] at approximately 100 FT AGL engine began to run noticeably rough; but maintained partial power. [I] immediately advised Tower that [I] was landing with a rough running engine. [I] was cleared to land XXR. [Corporate jet] on final for XXR was advised to prepare for possible go-around. Was able to land XXR and clear under power without further incident. [Corporate jet] was advised runway was clear and landed without incident. [I] taxied under power to parking spot for further investigation. [I] called Tower who advised that it was a non-reportable incident. Incident reaffirms wisdom of always briefing a departure emergency plan.

Data retrieved from NASA's ASRS site as of July 2013 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.