Narrative:

We were given a taxi clearance to taxi to runway 21L via taxiway C and taxiway a. At the end of taxiway a you must cross over the approach end of runway 25 to get to runway 21L. We thought because we had been given clearance to taxi to runway 21L we were permitted to cross all txwys and runways. ATC did not say hold short of runway 25. After we were at the hold short line for runway 21L and called ready for takeoff, the controller then advised us we had crossed an active runway (runway 25). We apologized, and said we thought we had been cleared to taxi to the end of runway 21L. The controller said 'that's all right.' we learned we will always question before crossing a runway.

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Original NASA ASRS Text

Title: A CPR CITATION II FLC IS ACCUSED BY TWR CTLR OF XING AN ACTIVE RWY, RWY 25, AT LUK WHEN THEY HAD BEEN CLRED TO RWY 21L.

Narrative: WE WERE GIVEN A TAXI CLRNC TO TAXI TO RWY 21L VIA TXWY C AND TXWY A. AT THE END OF TXWY A YOU MUST CROSS OVER THE APCH END OF RWY 25 TO GET TO RWY 21L. WE THOUGHT BECAUSE WE HAD BEEN GIVEN CLRNC TO TAXI TO RWY 21L WE WERE PERMITTED TO CROSS ALL TXWYS AND RWYS. ATC DID NOT SAY HOLD SHORT OF RWY 25. AFTER WE WERE AT THE HOLD SHORT LINE FOR RWY 21L AND CALLED READY FOR TKOF, THE CTLR THEN ADVISED US WE HAD CROSSED AN ACTIVE RWY (RWY 25). WE APOLOGIZED, AND SAID WE THOUGHT WE HAD BEEN CLRED TO TAXI TO THE END OF RWY 21L. THE CTLR SAID 'THAT'S ALL RIGHT.' WE LEARNED WE WILL ALWAYS QUESTION BEFORE XING A RWY.

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.