Narrative:

During taxi from the gate to the maintenance base, my partner, who was working the radio contact with the tower, misunderstood the tower to cross runway 28L&right, taxiway south to the gate. My partner called back 'clear to cross the runways 28, taxiway south to the gate.' the controller did not get back on the radio to challenge my partner's call back. As a result, we crossed runway 28L&right, taxiway south to the gate. We did not put anyone in danger because there was no aircraft taking off. The controller was new and I believe he did clear us to cross, but who knows. One factor may have been the time -- it was around XA00. The tower may have been tired.

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Original NASA ASRS Text

Title: A MAINT CREW WAS TAXIING A B737 FROM THE HANGAR TO THE TERMINAL AND CROSSED THE PARALLEL RWYS BELIEVING THEY HAD BEEN CLRED BY THE TWR.

Narrative: DURING TAXI FROM THE GATE TO THE MAINT BASE, MY PARTNER, WHO WAS WORKING THE RADIO CONTACT WITH THE TWR, MISUNDERSTOOD THE TWR TO CROSS RWY 28L&R, TXWY S TO THE GATE. MY PARTNER CALLED BACK 'CLR TO CROSS THE RWYS 28, TXWY S TO THE GATE.' THE CTLR DID NOT GET BACK ON THE RADIO TO CHALLENGE MY PARTNER'S CALL BACK. AS A RESULT, WE CROSSED RWY 28L&R, TXWY S TO THE GATE. WE DID NOT PUT ANYONE IN DANGER BECAUSE THERE WAS NO ACFT TAKING OFF. THE CTLR WAS NEW AND I BELIEVE HE DID CLR US TO CROSS, BUT WHO KNOWS. ONE FACTOR MAY HAVE BEEN THE TIME -- IT WAS AROUND XA00. THE TWR MAY HAVE BEEN TIRED.

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.