Narrative:

After requesting taxi, the tower controller cleared us to taxi runway 17R, taxiway south. After we crossed runway 17R at taxiway south, the tower controller asked us if we crossed the runway. We said we did and he told us we did not have clearance to cross. Possibly caused by fatigue.

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Original NASA ASRS Text

Title: DC9 CREW AT LBB CROSSED ASSIGNED RWY WITHOUT CLRNC.

Narrative: AFTER REQUESTING TAXI, THE TWR CTLR CLRED US TO TAXI RWY 17R, TXWY S. AFTER WE CROSSED RWY 17R AT TXWY S, THE TWR CTLR ASKED US IF WE CROSSED THE RWY. WE SAID WE DID AND HE TOLD US WE DID NOT HAVE CLRNC TO CROSS. POSSIBLY CAUSED BY FATIGUE.

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.