Narrative:

While taxiing for departure, the controller was operating ground and tower frequency. We were told to hold short of runway 24R or 'left.' the first officer read back hold short of runway 24L on 'left,' and got no response. The tower informed us that we had not been cleared to cross runway 24R! No traffic in the area.

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Original NASA ASRS Text

Title: UNAUTH RWY OP XING ENTRY IN A NIGHT OPERATION.

Narrative: WHILE TAXIING FOR DEP, THE CTLR WAS OPERATING GND AND TWR FREQ. WE WERE TOLD TO HOLD SHORT OF RWY 24R OR 'L.' THE FO READ BACK HOLD SHORT OF RWY 24L ON 'L,' AND GOT NO RESPONSE. THE TWR INFORMED US THAT WE HAD NOT BEEN CLRED TO CROSS RWY 24R! NO TFC IN THE AREA.

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.