Narrative:

We were getting a line check from an FAA examiner which was in the jump seat, from pit to jhw. After completing the before start checklist, after start checklist, we obtained a taxi clearance and taxied to the active runway. While taxiing we completed the taxi checklist and now we were #1 for takeoff. When we were cleared onto the runway for takeoff, we completed the line-up checklist and were ready for departure. Then the captain added power and we were rolling down the runway when a warning horn sounded. The captain immediately verified that the conditions were forward, which they were, and that the flaps were up, and they were, and that the trim was in the green arc for takeoff, which it wasn't. Therefore, the captain aborted the takeoff and we taxied clear of the runway. The captain reset the trim to an appropriate takeoff position and we taxied back to the active runway for departure. When taxiing back we encountered a heading comparator warning light which we were able to reset and extinguish the warning light. This happened twice. We completed all the appropriate checklists and again we were cleared for takeoff. On takeoff the heading comparator warning light illuminated again so the captain aborted the takeoff and taxied back to the gate. Maintenance was called and it was determined that one of the aircraft's computers had a problem and was grounded. The flight was canceled. Note: that new checklists were made to improve the flow of the previous ones, and were only implemented a few days prior to this.

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Original NASA ASRS Text

Title: ACR LTT CREW PERFORMS 2 TKOF ATTEMPTS AND 2 ABORTED TKOFS.

Narrative: WE WERE GETTING A LINE CHK FROM AN FAA EXAMINER WHICH WAS IN THE JUMP SEAT, FROM PIT TO JHW. AFTER COMPLETING THE BEFORE START CHKLIST, AFTER START CHKLIST, WE OBTAINED A TAXI CLRNC AND TAXIED TO THE ACTIVE RWY. WHILE TAXIING WE COMPLETED THE TAXI CHKLIST AND NOW WE WERE #1 FOR TKOF. WHEN WE WERE CLRED ONTO THE RWY FOR TKOF, WE COMPLETED THE LINE-UP CHKLIST AND WERE READY FOR DEP. THEN THE CAPT ADDED PWR AND WE WERE ROLLING DOWN THE RWY WHEN A WARNING HORN SOUNDED. THE CAPT IMMEDIATELY VERIFIED THAT THE CONDITIONS WERE FORWARD, WHICH THEY WERE, AND THAT THE FLAPS WERE UP, AND THEY WERE, AND THAT THE TRIM WAS IN THE GREEN ARC FOR TKOF, WHICH IT WASN'T. THEREFORE, THE CAPT ABORTED THE TKOF AND WE TAXIED CLR OF THE RWY. THE CAPT RESET THE TRIM TO AN APPROPRIATE TKOF POS AND WE TAXIED BACK TO THE ACTIVE RWY FOR DEP. WHEN TAXIING BACK WE ENCOUNTERED A HDG COMPARATOR WARNING LIGHT WHICH WE WERE ABLE TO RESET AND EXTINGUISH THE WARNING LIGHT. THIS HAPPENED TWICE. WE COMPLETED ALL THE APPROPRIATE CHKLISTS AND AGAIN WE WERE CLRED FOR TKOF. ON TKOF THE HDG COMPARATOR WARNING LIGHT ILLUMINATED AGAIN SO THE CAPT ABORTED THE TKOF AND TAXIED BACK TO THE GATE. MAINT WAS CALLED AND IT WAS DETERMINED THAT ONE OF THE ACFT'S COMPUTERS HAD A PROB AND WAS GNDED. THE FLT WAS CANCELED. NOTE: THAT NEW CHKLISTS WERE MADE TO IMPROVE THE FLOW OF THE PREVIOUS ONES, AND WERE ONLY IMPLEMENTED A FEW DAYS PRIOR TO THIS.

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.