Narrative:

Clearance delivery requested direction of takeoff. I stated runway 13. It should have been runway 31. Spx is an uncontrolled airport. A couple of aircraft (one a stearsman) were in the pattern but it appeared, especially the stearsman, were above pattern altitude on extended downwind. I departed and turned outbound below downwind aircraft to outside traffic before climbing to pattern altitude and assigned after takeoff heading. Called hou departure. Rest of flight ok. Mistakes: wrong runway (transposed numbers) and flew below and across downwind aircraft.

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Original NASA ASRS Text

Title: AN SMA PVT PLT TOOK OFF THE WRONG WAY AT AN UNCLTED ARPT.

Narrative: CLRNC DELIVERY REQUESTED DIRECTION OF TKOF. I STATED RWY 13. IT SHOULD HAVE BEEN RWY 31. SPX IS AN UNCTLED ARPT. A COUPLE OF ACFT (ONE A STEARSMAN) WERE IN THE PATTERN BUT IT APPEARED, ESPECIALLY THE STEARSMAN, WERE ABOVE PATTERN ALT ON EXTENDED DOWNWIND. I DEPARTED AND TURNED OUTBOUND BELOW DOWNWIND ACFT TO OUTSIDE TFC BEFORE CLBING TO PATTERN ALT AND ASSIGNED AFTER TKOF HDG. CALLED HOU DEP. REST OF FLT OK. MISTAKES: WRONG RWY (TRANSPOSED NUMBERS) AND FLEW BELOW AND ACROSS DOWNWIND ACFT.

Data retrieved from NASA's ASRS site as of July 2007 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.