Narrative:

First officer discovered takeoff warnings not working on preflight. My first reaction was 'this is a no-go item.' we looked at MEL and saw that some components of 'voice' warning could be inoperative. This planted seed so that when I went inside to call maintenance coordinator I wasn't sure of our status. I told maintenance coordinator the problem and he quickly issued a MEL number and control number authorizing dispatch. This 'convinced' me and I didn't question it further. We departed on schedule with a deferred item in logbook and placarded. A few days later I was called by our company fleet analyst and advised that we had flown with a no-go item.

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Original NASA ASRS Text

Title: FO RPTED ON PREFLT TKOF WARNING MALFUNCTION. CAPT CONTACTED MAINT WHO ISSUED A MEL NUMBER INDICATING IT WAS OK TO FLY THE ACFT. CAPT LATER ADVISED THE ACFT WAS NOT LEGAL TO FLY WITH THE DISCREPANCY.

Narrative: FO DISCOVERED TKOF WARNINGS NOT WORKING ON PREFLT. MY FIRST REACTION WAS 'THIS IS A NO-GO ITEM.' WE LOOKED AT MEL AND SAW THAT SOME COMPONENTS OF 'VOICE' WARNING COULD BE INOP. THIS PLANTED SEED SO THAT WHEN I WENT INSIDE TO CALL MAINT COORDINATOR I WASN'T SURE OF OUR STATUS. I TOLD MAINT COORDINATOR THE PROB AND HE QUICKLY ISSUED A MEL NUMBER AND CTL NUMBER AUTHORIZING DISPATCH. THIS 'CONVINCED' ME AND I DIDN'T QUESTION IT FURTHER. WE DEPARTED ON SCHEDULE WITH A DEFERRED ITEM IN LOGBOOK AND PLACARDED. A FEW DAYS LATER I WAS CALLED BY OUR COMPANY FLEET ANALYST AND ADVISED THAT WE HAD FLOWN WITH A NO-GO ITEM.

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.