Narrative:

As power was advanced for takeoff the confign warning horn sounded and the takeoff rejected. Finding all parameters normal, the speed brakes, flaps, trim and leading edge devices were cycled to ensure that sensors were positively engaged. Aircraft was positioned for takeoff and again as power was advanced, the horn sounded again. I notified company of our intention to return to the gate and requested maintenance. Once at the gate I observed the 'leading edge device' circuit breaker was out. In retrospect, the first officer had strapped in a couple of times before pushback and the strap or buckle had caught on the circuit breaker (located behind the first officer's seat headrest). We conferred with maintenance and they checked aircraft history to verify no chronic problem existed. Permission was given to reset the circuit breaker and proceed. Subsequent departure and flight was operations normal. An event report was filed to the chief pilot's office upon return to base at XA15 local. An 'information-only' write-up in the logbook was not accomplished in lieu of the event report and conversation with maintenance. The problem of shoulder straps catching on and tripping circuit breakers is common enough that a bulletin was issued in the past to address the situation. In the B737-200 it created a gear retraction malfunction since those are the circuit breakers located in that relative position behind the first officer. A guard or strap stiffener could be helpful to preclude this type of problem. In addition to the company event report, and the coordination with maintenance control, an information-only write up may have been useful in case a chronic problem with the confign warning system coincidentally began to develop. A contributing factor that led to the original corrective attempt is the fact the sensors and squat switches often operate in close tolerances and false indications are remedied by cycling the system which can establish more positive contact.

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Original NASA ASRS Text

Title: B737-200 FLC REJECTED TKOF AND RETURNED TO GATE AFTER 2 ATTEMPTS TO BRING UP ENG PWR PRODUCED TKOF CONFIGN WARNING HORN. PROB FOUND TO BE FO'S LAP BELT BUCKLE INADVERTENTLY CAUGHT AND PULLED ONE OR MORE CIRCUIT BREAKERS WHEN STRAPPING IN SEAT.

Narrative: AS PWR WAS ADVANCED FOR TKOF THE CONFIGN WARNING HORN SOUNDED AND THE TKOF REJECTED. FINDING ALL PARAMETERS NORMAL, THE SPD BRAKES, FLAPS, TRIM AND LEADING EDGE DEVICES WERE CYCLED TO ENSURE THAT SENSORS WERE POSITIVELY ENGAGED. ACFT WAS POSITIONED FOR TKOF AND AGAIN AS PWR WAS ADVANCED, THE HORN SOUNDED AGAIN. I NOTIFIED COMPANY OF OUR INTENTION TO RETURN TO THE GATE AND REQUESTED MAINT. ONCE AT THE GATE I OBSERVED THE 'LEADING EDGE DEVICE' CIRCUIT BREAKER WAS OUT. IN RETROSPECT, THE FO HAD STRAPPED IN A COUPLE OF TIMES BEFORE PUSHBACK AND THE STRAP OR BUCKLE HAD CAUGHT ON THE CIRCUIT BREAKER (LOCATED BEHIND THE FO'S SEAT HEADREST). WE CONFERRED WITH MAINT AND THEY CHKED ACFT HISTORY TO VERIFY NO CHRONIC PROB EXISTED. PERMISSION WAS GIVEN TO RESET THE CIRCUIT BREAKER AND PROCEED. SUBSEQUENT DEP AND FLT WAS OPS NORMAL. AN EVENT RPT WAS FILED TO THE CHIEF PLT'S OFFICE UPON RETURN TO BASE AT XA15 LCL. AN 'INFO-ONLY' WRITE-UP IN THE LOGBOOK WAS NOT ACCOMPLISHED IN LIEU OF THE EVENT RPT AND CONVERSATION WITH MAINT. THE PROB OF SHOULDER STRAPS CATCHING ON AND TRIPPING CIRCUIT BREAKERS IS COMMON ENOUGH THAT A BULLETIN WAS ISSUED IN THE PAST TO ADDRESS THE SIT. IN THE B737-200 IT CREATED A GEAR RETRACTION MALFUNCTION SINCE THOSE ARE THE CIRCUIT BREAKERS LOCATED IN THAT RELATIVE POS BEHIND THE FO. A GUARD OR STRAP STIFFENER COULD BE HELPFUL TO PRECLUDE THIS TYPE OF PROB. IN ADDITION TO THE COMPANY EVENT RPT, AND THE COORD WITH MAINT CTL, AN INFO-ONLY WRITE UP MAY HAVE BEEN USEFUL IN CASE A CHRONIC PROB WITH THE CONFIGN WARNING SYS COINCIDENTALLY BEGAN TO DEVELOP. A CONTRIBUTING FACTOR THAT LED TO THE ORIGINAL CORRECTIVE ATTEMPT IS THE FACT THE SENSORS AND SQUAT SWITCHES OFTEN OPERATE IN CLOSE TOLERANCES AND FALSE INDICATIONS ARE REMEDIED BY CYCLING THE SYS WHICH CAN ESTABLISH MORE POSITIVE CONTACT.

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.