Narrative:

DC9 was instructed to taxi to runway 11L. Both I and ground control noticed the DC9 passing taxiway A4 and tried to reach him prior to him crossing runway 21, but were unsuccessful until the aircraft was already on runway 21.

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Original NASA ASRS Text

Title: FLC MISINTERPRETED OR WAS UNFAMILIAR WITH THE TAXI RTE TO RWY 11L AT TUS WHICH RESULTED IN A TRANSGRESSION ONTO RWY 21. ATC RPTR DID NOT INDICATE THAT THERE WAS ANY OTHER TFC INVOLVED.

Narrative: DC9 WAS INSTRUCTED TO TAXI TO RWY 11L. BOTH I AND GND CTL NOTICED THE DC9 PASSING TXWY A4 AND TRIED TO REACH HIM PRIOR TO HIM XING RWY 21, BUT WERE UNSUCCESSFUL UNTIL THE ACFT WAS ALREADY ON RWY 21.

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.