Narrative:

Cleared to taxi to 19L via delta. Taxied to the end of runway, completed run-up, and called tower for takeoff. Tower responded with 'taxi into position and hold.' I did so. Tower called and asked me 'location, please?' I looked at runway #'south and idented 19R and asked if I should clear. Tower said 'no,' and cleared takeoff. Considerations: 1) I was unfamiliar with airport. 2) immediately preceding flight I had problems with FBO who had charged me for fuel, but had not done so. 3) as I taxied, I recall identing 19L as being on my left (error). Corrective action: never taxi west/O an airport diagram in my lap. Verify and double check runway and taxiway identify. Concern: this one really got my attention. I could easily have precipitated an accident.

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Original NASA ASRS Text

Title: GA SMA TOOK TKOF POSITION ON THE WRONG RWY AT LAS. TWR SAW THE ERROR AND CHANGED TKOF CLRNC.

Narrative: CLRED TO TAXI TO 19L VIA DELTA. TAXIED TO THE END OF RWY, COMPLETED RUN-UP, AND CALLED TWR FOR TKOF. TWR RESPONDED WITH 'TAXI INTO POS AND HOLD.' I DID SO. TWR CALLED AND ASKED ME 'LOCATION, PLEASE?' I LOOKED AT RWY #'S AND IDENTED 19R AND ASKED IF I SHOULD CLEAR. TWR SAID 'NO,' AND CLRED TKOF. CONSIDERATIONS: 1) I WAS UNFAMILIAR WITH ARPT. 2) IMMEDIATELY PRECEDING FLT I HAD PROBS WITH FBO WHO HAD CHARGED ME FOR FUEL, BUT HAD NOT DONE SO. 3) AS I TAXIED, I RECALL IDENTING 19L AS BEING ON MY LEFT (ERROR). CORRECTIVE ACTION: NEVER TAXI W/O AN ARPT DIAGRAM IN MY LAP. VERIFY AND DOUBLE CHK RWY AND TXWY IDENT. CONCERN: THIS ONE REALLY GOT MY ATTN. I COULD EASILY HAVE PRECIPITATED AN ACCIDENT.

Data retrieved from NASA's ASRS site as of August 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.