Narrative:

When advancing power to takeoff, takeoff warning horn sounded. Immediate rechk of spdbrake, parking brake light, flaps, and takeoff trim setting confirmed normal takeoff settings. Takeoff was discontinued at approximately 30 KTS and taxi off runway 05 at clt was accomplished with no use of brakes until turning off at normal taxi speed. Another rechk of the position of items on takeoff warning circuit after exiting runway produced no different result until the speed brake, which was in the down detent position, was given a firm push forward against its stop. At this point the takeoff warning horn stopped sounding when tested. We suspected the spdbrake part of the circuit was at fault but weren't sure at this point. However the system was working normally and we saw no reason to return to the gate for maintenance. The before takeoff checklist was run again and a normal takeoff was accomplished. The cause of this problem was probably a touchy switch that completes the speed brake part of the takeoff warning circuit. This was the second consecutive leg we flew in this particular airplane and no problem was encountered on the previous leg. The next leg, we tested the takeoff warning circuit early, pushing up a throttle momentarily. The warning sounded, we tapped the speed brake level forward and the warning stopped. This confirmed, in our minds, that the speed brake part of the circuit was the actual problem. Again the system was working normally and we saw no reason to return to the gate for maintenance. We then wrote that particular item in the logbook for maintenance to inspect at the next stop. I have no suggestions on how to prevent this from occurring again. Mechanical things break and small switches are subject to contamination from dirt, etc. An incident like this is normally not a valid reason to return to the gate for maintenance, when viewed through the eyes of a cautious, competent pilot who exercises good judgment. The reason this report is necessary is the vindictive attitude of the FAA, which assumes that such a takeoff warning indicates the crew failed to run the checklist properly. Crews shouldn't feel pressured to return to the gate for maintenance for minor items that are correctable without the aid of maintenance, just because their occurrence caused an aborted takeoff.

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Original NASA ASRS Text

Title: ACR MLG TKOF ABORTED ACCOUNT FAULTY SPOILER SPD BRAKE HANDLE POS SENSING SWITCH. PROB KNOWN, FLT CONTINUED.

Narrative: WHEN ADVANCING PWR TO TKOF, TKOF WARNING HORN SOUNDED. IMMEDIATE RECHK OF SPDBRAKE, PARKING BRAKE LIGHT, FLAPS, AND TKOF TRIM SETTING CONFIRMED NORMAL TKOF SETTINGS. TKOF WAS DISCONTINUED AT APPROX 30 KTS AND TAXI OFF RWY 05 AT CLT WAS ACCOMPLISHED WITH NO USE OF BRAKES UNTIL TURNING OFF AT NORMAL TAXI SPD. ANOTHER RECHK OF THE POS OF ITEMS ON TKOF WARNING CIRCUIT AFTER EXITING RWY PRODUCED NO DIFFERENT RESULT UNTIL THE SPD BRAKE, WHICH WAS IN THE DOWN DETENT POS, WAS GIVEN A FIRM PUSH FORWARD AGAINST ITS STOP. AT THIS POINT THE TKOF WARNING HORN STOPPED SOUNDING WHEN TESTED. WE SUSPECTED THE SPDBRAKE PART OF THE CIRCUIT WAS AT FAULT BUT WEREN'T SURE AT THIS POINT. HOWEVER THE SYSTEM WAS WORKING NORMALLY AND WE SAW NO REASON TO RETURN TO THE GATE FOR MAINT. THE BEFORE TKOF CHKLIST WAS RUN AGAIN AND A NORMAL TKOF WAS ACCOMPLISHED. THE CAUSE OF THIS PROB WAS PROBABLY A TOUCHY SWITCH THAT COMPLETES THE SPD BRAKE PART OF THE TKOF WARNING CIRCUIT. THIS WAS THE SECOND CONSECUTIVE LEG WE FLEW IN THIS PARTICULAR AIRPLANE AND NO PROB WAS ENCOUNTERED ON THE PREVIOUS LEG. THE NEXT LEG, WE TESTED THE TKOF WARNING CIRCUIT EARLY, PUSHING UP A THROTTLE MOMENTARILY. THE WARNING SOUNDED, WE TAPPED THE SPD BRAKE LEVEL FORWARD AND THE WARNING STOPPED. THIS CONFIRMED, IN OUR MINDS, THAT THE SPD BRAKE PART OF THE CIRCUIT WAS THE ACTUAL PROB. AGAIN THE SYSTEM WAS WORKING NORMALLY AND WE SAW NO REASON TO RETURN TO THE GATE FOR MAINT. WE THEN WROTE THAT PARTICULAR ITEM IN THE LOGBOOK FOR MAINT TO INSPECT AT THE NEXT STOP. I HAVE NO SUGGESTIONS ON HOW TO PREVENT THIS FROM OCCURRING AGAIN. MECHANICAL THINGS BREAK AND SMALL SWITCHES ARE SUBJECT TO CONTAMINATION FROM DIRT, ETC. AN INCIDENT LIKE THIS IS NORMALLY NOT A VALID REASON TO RETURN TO THE GATE FOR MAINT, WHEN VIEWED THROUGH THE EYES OF A CAUTIOUS, COMPETENT PLT WHO EXERCISES GOOD JUDGMENT. THE REASON THIS RPT IS NECESSARY IS THE VINDICTIVE ATTITUDE OF THE FAA, WHICH ASSUMES THAT SUCH A TKOF WARNING INDICATES THE CREW FAILED TO RUN THE CHKLIST PROPERLY. CREWS SHOULDN'T FEEL PRESSURED TO RETURN TO THE GATE FOR MAINT FOR MINOR ITEMS THAT ARE CORRECTABLE WITHOUT THE AID OF MAINT, JUST BECAUSE THEIR OCCURRENCE CAUSED AN ABORTED TKOF.

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.