Narrative:

We were at iad and cleared for takeoff on runway 30. We entered the runway from taxiway Q and were in position to take off when tower cleared another aircraft into position and hold. I thought the other aircraft was behind us on taxiway Q. At this time, I noticed a citation cj on taxiway Z. As I brought the throttles up and called for 'set power,' I looked at the cj to make sure he was stopping, but he continued toward the runway. At this time I aborted the takeoff and went left of centerline about 20 ft as the cj entered the runway from taxiway Z. Just as I was aborting, someone on tower frequency yelled 'stop.' the cj's nose was on the runway when we went by him. We were doing less than 60 KTS when we aborted and my first officer didn't see anything because he was setting the power. I asked tower if it was anything we did and they said no. They thought the cj was on another taxiway.

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Original NASA ASRS Text

Title: CE650 FLT CREW ABORTS THEIR TKOF AFTER A CITATION JET TAXIES ONTO THE ACTIVE RWY AT IAD DUE TO POS AND HOLD IAD TWR CLRNC.

Narrative: WE WERE AT IAD AND CLRED FOR TKOF ON RWY 30. WE ENTERED THE RWY FROM TXWY Q AND WERE IN POS TO TAKE OFF WHEN TWR CLRED ANOTHER ACFT INTO POS AND HOLD. I THOUGHT THE OTHER ACFT WAS BEHIND US ON TXWY Q. AT THIS TIME, I NOTICED A CITATION CJ ON TXWY Z. AS I BROUGHT THE THROTTLES UP AND CALLED FOR 'SET PWR,' I LOOKED AT THE CJ TO MAKE SURE HE WAS STOPPING, BUT HE CONTINUED TOWARD THE RWY. AT THIS TIME I ABORTED THE TKOF AND WENT L OF CTRLINE ABOUT 20 FT AS THE CJ ENTERED THE RWY FROM TXWY Z. JUST AS I WAS ABORTING, SOMEONE ON TWR FREQ YELLED 'STOP.' THE CJ'S NOSE WAS ON THE RWY WHEN WE WENT BY HIM. WE WERE DOING LESS THAN 60 KTS WHEN WE ABORTED AND MY FO DIDN'T SEE ANYTHING BECAUSE HE WAS SETTING THE PWR. I ASKED TWR IF IT WAS ANYTHING WE DID AND THEY SAID NO. THEY THOUGHT THE CJ WAS ON ANOTHER TXWY.

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.