Narrative:

We started our engines and performed a taxi checklist. Receiving a takeoff clearance, we performed the before checklist entering the runway. As we performed the checklist, the takeoff warning (flaps) sounded and we taxied clear of runway 29. We cycled the flaps to up and back to a takeoff setting of 18 degrees. Once again, we performed a takeoff checklist and again received a flap takeoff warning. We taxied down runway 29 and exited at taxiway D as instructed by ATC. The problem was rectified by resetting the flap takeoff condition computer to flap 18 degrees, rather than flaps 11 degrees, the normal setting. At that point, we departed for atl uneventfully. A flaps 18 degree takeoff is a non normal flap setting. Although the flaps were positioned at the correct setting of 18 degrees and indicated 18 degrees, the takeoff condition computer was misset. The takeoff condition computer was misset during the before start checklist, but it was still corrected by the proper use of the takeoff checklist.

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Original NASA ASRS Text

Title: FLT CREW OF MD80 REJECT 2 TKOFS FROM PWM WHEN TKOF WARNING HORN AND FLAPS ALERT SOUNDED. DISCOVERED ACFT TKOF PERFORMANCE COMPUTER IMPROPERLY PROGRAMMED.

Narrative: WE STARTED OUR ENGS AND PERFORMED A TAXI CHKLIST. RECEIVING A TKOF CLRNC, WE PERFORMED THE BEFORE CHKLIST ENTERING THE RWY. AS WE PERFORMED THE CHKLIST, THE TKOF WARNING (FLAPS) SOUNDED AND WE TAXIED CLR OF RWY 29. WE CYCLED THE FLAPS TO UP AND BACK TO A TKOF SETTING OF 18 DEGS. ONCE AGAIN, WE PERFORMED A TKOF CHKLIST AND AGAIN RECEIVED A FLAP TKOF WARNING. WE TAXIED DOWN RWY 29 AND EXITED AT TXWY D AS INSTRUCTED BY ATC. THE PROB WAS RECTIFIED BY RESETTING THE FLAP TKOF CONDITION COMPUTER TO FLAP 18 DEGS, RATHER THAN FLAPS 11 DEGS, THE NORMAL SETTING. AT THAT POINT, WE DEPARTED FOR ATL UNEVENTFULLY. A FLAPS 18 DEG TKOF IS A NON NORMAL FLAP SETTING. ALTHOUGH THE FLAPS WERE POSITIONED AT THE CORRECT SETTING OF 18 DEGS AND INDICATED 18 DEGS, THE TKOF CONDITION COMPUTER WAS MISSET. THE TKOF CONDITION COMPUTER WAS MISSET DURING THE BEFORE START CHKLIST, BUT IT WAS STILL CORRECTED BY THE PROPER USE OF THE TKOF CHKLIST.

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.