Narrative:

During engine spool up for takeoff, the takeoff warning horn sounded. First officer immediately noticed flaps not in position 1 detent and moved flap handle to the position 1 detent. After a few seconds thrust levers were again advanced, and (takeoff) continued normally. After we had time to evaluate the situation, here is what we came up with: the flaps were not in position 1 for takeoff. They were either not completely selected in the flap 1 detent, or in the up detent -- we could not determine which. Neither pilot could remember positively whether or not the 'before takeoff checklist' concerning the flaps was completed. There is evidence that the before takeoff checklist was not completed because of all the ground confusion. (Initially we both thought we did it, but after much discussion and thought, we cannot be sure we did.)

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Original NASA ASRS Text

Title: FLC OF AN MLG FAILED TO SET THE FLAPS FOR TKOF DUE TO NOT COMPLETING THE BEFORE TKOF CHKLIST.

Narrative: DURING ENG SPOOL UP FOR TKOF, THE TKOF WARNING HORN SOUNDED. FO IMMEDIATELY NOTICED FLAPS NOT IN POS 1 DETENT AND MOVED FLAP HANDLE TO THE POS 1 DETENT. AFTER A FEW SECONDS THRUST LEVERS WERE AGAIN ADVANCED, AND (TKOF) CONTINUED NORMALLY. AFTER WE HAD TIME TO EVALUATE THE SIT, HERE IS WHAT WE CAME UP WITH: THE FLAPS WERE NOT IN POS 1 FOR TKOF. THEY WERE EITHER NOT COMPLETELY SELECTED IN THE FLAP 1 DETENT, OR IN THE UP DETENT -- WE COULD NOT DETERMINE WHICH. NEITHER PLT COULD REMEMBER POSITIVELY WHETHER OR NOT THE 'BEFORE TKOF CHKLIST' CONCERNING THE FLAPS WAS COMPLETED. THERE IS EVIDENCE THAT THE BEFORE TKOF CHKLIST WAS NOT COMPLETED BECAUSE OF ALL THE GND CONFUSION. (INITIALLY WE BOTH THOUGHT WE DID IT, BUT AFTER MUCH DISCUSSION AND THOUGHT, WE CANNOT BE SURE WE DID.)

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.