Narrative:

Flight was cleared onto runway 17R at dfw to hold. Several landing aircraft were then cleared across the departure end of runway 17R. When it appeared all that had been cleared across were across, we were cleared for takeoff. I noticed that there was an air carrier widebody transport still holding short of runway 17R. As I advanced power I noticed that the widebody transport had started moving forward. I retarded the power. The widebody transport did cross the runway. While he was crossing, the tower stated that we were cleared for takeoff. Again, we waited until the widebody transport was clear of the runway and then asked tower to confirm we were now cleared for takeoff. I don't believe the tower ever knew that there was another plane on the runway during the time we were cleared to go.

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Original NASA ASRS Text

Title: ACR CLEARED FOR TKOF SEES WDB STARTING TO CROSS RWY. TWR AGAIN STATES CLEARED FOR TKOF. FLT CREW RETARDED PWR AND WAITED UNTIL WDB CROSSED.

Narrative: FLT WAS CLRED ONTO RWY 17R AT DFW TO HOLD. SEVERAL LNDG ACFT WERE THEN CLRED ACROSS THE DEP END OF RWY 17R. WHEN IT APPEARED ALL THAT HAD BEEN CLRED ACROSS WERE ACROSS, WE WERE CLRED FOR TKOF. I NOTICED THAT THERE WAS AN ACR WDB STILL HOLDING SHORT OF RWY 17R. AS I ADVANCED PWR I NOTICED THAT THE WDB HAD STARTED MOVING FORWARD. I RETARDED THE PWR. THE WDB DID CROSS THE RWY. WHILE HE WAS XING, THE TWR STATED THAT WE WERE CLRED FOR TKOF. AGAIN, WE WAITED UNTIL THE WDB WAS CLR OF THE RWY AND THEN ASKED TWR TO CONFIRM WE WERE NOW CLRED FOR TKOF. I DON'T BELIEVE THE TWR EVER KNEW THAT THERE WAS ANOTHER PLANE ON THE RWY DURING THE TIME WE WERE CLRED TO GO.

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.