Narrative:

I was training a developmental who gave an incorrect taxi clearance and as soon as I heard the incorrect portion of the taxi instructions, I stopped listening and missed the bigger mistake which was the issuance to hold short of the wrong runway. While discussing the initial mistake with the trainee, I also missed the pilot's readback. Thus, small aircraft X crossed the runway without coordination. It was discovered by air carrier Y who was cleared for takeoff on runway 30L but didn't roll because he thought small aircraft X was taxiing too quickly to hold short. So, he questioned the local controller, who questioned us and we initially thought it was a pilot deviation. But after listening to the tape, the trainee clearly stated hold short of the wrong runway, the pilot read back the instructions as issued and proceeded accordingly.

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Original NASA ASRS Text

Title: UNCOORD RWY XING ENTRY.

Narrative: I WAS TRAINING A DEVELOPMENTAL WHO GAVE AN INCORRECT TAXI CLRNC AND AS SOON AS I HEARD THE INCORRECT PORTION OF THE TAXI INSTRUCTIONS, I STOPPED LISTENING AND MISSED THE BIGGER MISTAKE WHICH WAS THE ISSUANCE TO HOLD SHORT OF THE WRONG RWY. WHILE DISCUSSING THE INITIAL MISTAKE WITH THE TRAINEE, I ALSO MISSED THE PLT'S READBACK. THUS, SMA X CROSSED THE RWY WITHOUT COORD. IT WAS DISCOVERED BY ACR Y WHO WAS CLRED FOR TKOF ON RWY 30L BUT DIDN'T ROLL BECAUSE HE THOUGHT SMA X WAS TAXIING TOO QUICKLY TO HOLD SHORT. SO, HE QUESTIONED THE LCL CTLR, WHO QUESTIONED US AND WE INITIALLY THOUGHT IT WAS A PLTDEV. BUT AFTER LISTENING TO THE TAPE, THE TRAINEE CLRLY STATED HOLD SHORT OF THE WRONG RWY, THE PLT READ BACK THE INSTRUCTIONS AS ISSUED AND PROCEEDED ACCORDINGLY.

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.