Narrative:

[I had a] possible intrusion into class D airspace. Aircraft was temporarily deviated from intended flight path and pilot descended from altitude due to rough engine operation. Decision was made to land when engine operation progressively got worse. Application of carburetor heat; lean mixture and abrupt change in pitch attitude temporarily resolved the engine problem. Upon landing; fuel contamination was found.

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Original NASA ASRS Text

Title: PA28 pilot reports a possible Class D airspace incursion while attempting to troubleshoot a rough running engine. The reporter elects to land at the airport in question where contaminated fuel is discovered.

Narrative: [I had a] possible intrusion into Class D Airspace. Aircraft was temporarily deviated from intended flight path and pilot descended from altitude due to rough engine operation. Decision was made to land when engine operation progressively got worse. Application of carburetor heat; lean mixture and abrupt change in pitch attitude temporarily resolved the engine problem. Upon landing; fuel contamination was found.

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.