Narrative:

Before taxiing I was having problems with my audio box. My head set was cutting in and out. I believed the controller had cleared us to runway 28L. I taxied to runway 28L and on the way I xed runway 28C. The airport was under heavy construction and it is not unusual for either runway to be closed. Upon arriving at runway 28L the controller said he had cleared us to runway 28C and that we had xed an active runway.

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Original NASA ASRS Text

Title: MLG CLEARED TO RWY 28C. THOUGHT CLEARED TO RWY 28L AND CROSSED RWY 28C WHILE GETTING THERE.

Narrative: BEFORE TAXIING I WAS HAVING PROBS WITH MY AUDIO BOX. MY HEAD SET WAS CUTTING IN AND OUT. I BELIEVED THE CTLR HAD CLRED US TO RWY 28L. I TAXIED TO RWY 28L AND ON THE WAY I XED RWY 28C. THE ARPT WAS UNDER HEAVY CONSTRUCTION AND IT IS NOT UNUSUAL FOR EITHER RWY TO BE CLOSED. UPON ARRIVING AT RWY 28L THE CTLR SAID HE HAD CLRED US TO RWY 28C AND THAT WE HAD XED AN ACTIVE RWY.

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.