Narrative:

Crew misinterped signage and commercial chart to mistake taxiway M for taxiway a extension. Held short of runway 1L on taxiway M and informed tower of error.

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Original NASA ASRS Text

Title: AN AIR CARGO FLC TAKES THE WRONG TURN AND ENDS UP ON TXWY M INSTEAD OF TXWY A, RWY 1R, AND ADVISES ATC OF HOLDING SHORT OF RWY 1L AT SFO, CA.

Narrative: CREW MISINTERPED SIGNAGE AND COMMERCIAL CHART TO MISTAKE TXWY M FOR TXWY A EXTENSION. HELD SHORT OF RWY 1L ON TXWY M AND INFORMED TWR OF ERROR.

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.