Narrative:

Issued takeoff clearance. Upon advancing throttles, the takeoff warning horn sounded. Idled throttles and again verified trim, flap setting and speed brake in down detent. Again advanced throttles and horn sounded. Asked tower to clear runway. Upon clearing runway, recycled flaps, spdbrake, advanced throttles and now, no horn. Asked for clearance and then took off. Engines were never spooled and speed never above walking speed before clearing runway.

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Original NASA ASRS Text

Title: ACR HAS WARNING HORN SOUND AS THROTTLES ADVANCED. VERIFIED FLAPS, TRIM, SPD BRAKES DOWN, ADVANCED AGAIN. HORN SOUNDED. CLRED RWY, RECYCLED EQUIP, ADVANCED THROTTLES, NO HORN. NORMAL TKOF.

Narrative: ISSUED TKOF CLRNC. UPON ADVANCING THROTTLES, THE TKOF WARNING HORN SOUNDED. IDLED THROTTLES AND AGAIN VERIFIED TRIM, FLAP SETTING AND SPD BRAKE IN DOWN DETENT. AGAIN ADVANCED THROTTLES AND HORN SOUNDED. ASKED TWR TO CLR RWY. UPON CLRING RWY, RECYCLED FLAPS, SPDBRAKE, ADVANCED THROTTLES AND NOW, NO HORN. ASKED FOR CLRNC AND THEN TOOK OFF. ENGS WERE NEVER SPOOLED AND SPD NEVER ABOVE WALKING SPD BEFORE CLRING RWY.

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.