Narrative:

After normal preflight and boarding of passenger, flight departed gate on schedule, started engines and was cleared to taxi to runway 25 for takeoff. I called for the pretkof checklist during taxi out after the cabin was reported secure by senior F/a. The checklist was completed well before arriving at departure runway. Flight was cleared for takeoff by tower, the below the line portion of the pretkof checklist was accomplished while going into position as per our normal procedures. The takeoff warning horn sounded as the throttles were advanced and we discontinued takeoff immediately (engines had not spooled up) and taxied clear of runway. The flaps were up. Both the copilot and I are normally very thorough and attention-to-detail oriented, especially when it comes to checklists. Neither of us could explain or remember how we both could have missed this very important item on the checklist, but we did. After positioning the flaps to proper position and doing the checklist again in its entirety, I made a short but honest passenger announcement before the flight continued west/O further incident. As best as I can remember there were no major distrs during our taxi out. The WX was clear, no wind, and we were the only aircraft moving at the time. The cabin had been secured and the cockpit door was closed. Both the copilot and I had at least 8 hours of sleep. Copilot awoke early enough to run prior to joining me for breakfast. In this case, even with human error involved, the system worked.

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Original NASA ASRS Text

Title: TKOF WARNING HORN SOUNDED. TKOF ABORTED. FOUND FLAPS IN UP POSITION ON MLG ACR.

Narrative: AFTER NORMAL PREFLT AND BOARDING OF PAX, FLT DEPARTED GATE ON SCHEDULE, STARTED ENGS AND WAS CLRED TO TAXI TO RWY 25 FOR TKOF. I CALLED FOR THE PRETKOF CHKLIST DURING TAXI OUT AFTER THE CABIN WAS RPTED SECURE BY SENIOR F/A. THE CHKLIST WAS COMPLETED WELL BEFORE ARRIVING AT DEP RWY. FLT WAS CLRED FOR TKOF BY TWR, THE BELOW THE LINE PORTION OF THE PRETKOF CHKLIST WAS ACCOMPLISHED WHILE GOING INTO POS AS PER OUR NORMAL PROCS. THE TKOF WARNING HORN SOUNDED AS THE THROTTLES WERE ADVANCED AND WE DISCONTINUED TKOF IMMEDIATELY (ENGS HAD NOT SPOOLED UP) AND TAXIED CLR OF RWY. THE FLAPS WERE UP. BOTH THE COPLT AND I ARE NORMALLY VERY THOROUGH AND ATTN-TO-DETAIL ORIENTED, ESPECIALLY WHEN IT COMES TO CHKLISTS. NEITHER OF US COULD EXPLAIN OR REMEMBER HOW WE BOTH COULD HAVE MISSED THIS VERY IMPORTANT ITEM ON THE CHKLIST, BUT WE DID. AFTER POSITIONING THE FLAPS TO PROPER POS AND DOING THE CHKLIST AGAIN IN ITS ENTIRETY, I MADE A SHORT BUT HONEST PAX ANNOUNCEMENT BEFORE THE FLT CONTINUED W/O FURTHER INCIDENT. AS BEST AS I CAN REMEMBER THERE WERE NO MAJOR DISTRS DURING OUR TAXI OUT. THE WX WAS CLR, NO WIND, AND WE WERE THE ONLY ACFT MOVING AT THE TIME. THE CABIN HAD BEEN SECURED AND THE COCKPIT DOOR WAS CLOSED. BOTH THE COPLT AND I HAD AT LEAST 8 HRS OF SLEEP. COPLT AWOKE EARLY ENOUGH TO RUN PRIOR TO JOINING ME FOR BREAKFAST. IN THIS CASE, EVEN WITH HUMAN ERROR INVOLVED, THE SYS WORKED.

Data retrieved from NASA's ASRS site as of August 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.