Narrative:

I was notified in may of a deferral I performed in march. I was told that I had deferred an engine fire loop and after several flights later and two maintenance line checks a pilot noticed that the switch was in the wrong position. The aircraft apparently had been flying around with no fire protection because the switch was on the deferral loop. I know this was not the way I deferred it because I remember going through the troubleshooting and deferral over the phone with maintenance control. We made sure during our discussion that the switch was in the proper position. The switch getting pushed into the inoperative loop occurred after I was done flying that aircraft. It was done by another pilot or mechanic during a line check.

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Original NASA ASRS Text

Title: A CAPTAIN REPORTS MAKING A DEFERRAL PER THE MEL OF A SINGLE FIRE WARNING LOOP. LATER IT WAS REPORTED THE SWITCH WAS IN THE INOPERATIVE LOOP POSITION.

Narrative: I WAS NOTIFIED IN MAY OF A DEFERRAL I PERFORMED IN MARCH. I WAS TOLD THAT I HAD DEFERRED AN ENGINE FIRE LOOP AND AFTER SEVERAL FLIGHTS LATER AND TWO MAINTENANCE LINE CHECKS A PILOT NOTICED THAT THE SWITCH WAS IN THE WRONG POSITION. THE AIRCRAFT APPARENTLY HAD BEEN FLYING AROUND WITH NO FIRE PROTECTION BECAUSE THE SWITCH WAS ON THE DEFERRAL LOOP. I KNOW THIS WAS NOT THE WAY I DEFERRED IT BECAUSE I REMEMBER GOING THROUGH THE TROUBLESHOOTING AND DEFERRAL OVER THE PHONE WITH MAINTENANCE CONTROL. WE MADE SURE DURING OUR DISCUSSION THAT THE SWITCH WAS IN THE PROPER POSITION. THE SWITCH GETTING PUSHED INTO THE INOP LOOP OCCURRED AFTER I WAS DONE FLYING THAT AIRCRAFT. IT WAS DONE BY ANOTHER PILOT OR MECHANIC DURING A LINE CHECK.

Data retrieved from NASA's ASRS site as of January 2009 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.