Narrative:

We were pushed back for taxi. Ground control then cleared us to taxi to runway 21. There was only 1 way to get to runway 21 from the way we were positioned on the ramp after pushback. We crossed runway 21 at taxiway T and then turned right on taxiway north. The controller then said, 'why didn't you use taxiway Q to get to runway 21?' we said we weren't cleared to taxi to runway 21 via taxiway Q. The controller assumed we were familiar with how to get to runway 21. We both were very unfamiliar with sat. I personally had forgotten that a clearance to taxi to runway 21 is not a clearance to cross runway 21. I was also a little distraction as the captain taxied the aircraft. I'm not sure by what, but I remember my situational awareness was low.

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Original NASA ASRS Text

Title: A TXWY AND RWY INCURSION OCCURRED DURING A NIGHT OP WHEN THE CREW OF A B767 CARGO FLT CROSSED THE ACTIVE RWY ON THE WRONG TXWY AT SAT, TX.

Narrative: WE WERE PUSHED BACK FOR TAXI. GND CTL THEN CLRED US TO TAXI TO RWY 21. THERE WAS ONLY 1 WAY TO GET TO RWY 21 FROM THE WAY WE WERE POSITIONED ON THE RAMP AFTER PUSHBACK. WE CROSSED RWY 21 AT TXWY T AND THEN TURNED R ON TXWY N. THE CTLR THEN SAID, 'WHY DIDN'T YOU USE TXWY Q TO GET TO RWY 21?' WE SAID WE WEREN'T CLRED TO TAXI TO RWY 21 VIA TXWY Q. THE CTLR ASSUMED WE WERE FAMILIAR WITH HOW TO GET TO RWY 21. WE BOTH WERE VERY UNFAMILIAR WITH SAT. I PERSONALLY HAD FORGOTTEN THAT A CLRNC TO TAXI TO RWY 21 IS NOT A CLRNC TO CROSS RWY 21. I WAS ALSO A LITTLE DISTR AS THE CAPT TAXIED THE ACFT. I'M NOT SURE BY WHAT, BUT I REMEMBER MY SITUATIONAL AWARENESS WAS LOW.

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.