Narrative:

A problem developed with autoplt/altitude alert system. It would not set in 100' increments as designed. Maintenance could not correct. Dispatch and maintenance control deferred the autoplt system per the MEL. However, after departing on the second leg of release, I determined that it was not an autoplt problem but an altitude alerting function which cannot be deferred. I then contacted dispatch and maintenance control to evaluate. After discussion we agreed that the system was mistakenly deferred under the wrong item and that it indeed could not be deferred. No further flts were made until the problem was corrected. I feel that the combined nature of the autoplt altitude alert system and the wording of the MEL led to this mistake.

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Original NASA ASRS Text

Title: ACR MLG CAPT THINKS THEY FAILED TO COMPLY WITH MINIMUM EQUIPMENT LIST REQUIREMENT.

Narrative: A PROB DEVELOPED WITH AUTOPLT/ALT ALERT SYS. IT WOULD NOT SET IN 100' INCREMENTS AS DESIGNED. MAINT COULD NOT CORRECT. DISPATCH AND MAINT CTL DEFERRED THE AUTOPLT SYS PER THE MEL. HOWEVER, AFTER DEPARTING ON THE SECOND LEG OF RELEASE, I DETERMINED THAT IT WAS NOT AN AUTOPLT PROB BUT AN ALT ALERTING FUNCTION WHICH CANNOT BE DEFERRED. I THEN CONTACTED DISPATCH AND MAINT CTL TO EVALUATE. AFTER DISCUSSION WE AGREED THAT THE SYS WAS MISTAKENLY DEFERRED UNDER THE WRONG ITEM AND THAT IT INDEED COULD NOT BE DEFERRED. NO FURTHER FLTS WERE MADE UNTIL THE PROB WAS CORRECTED. I FEEL THAT THE COMBINED NATURE OF THE AUTOPLT ALT ALERT SYS AND THE WORDING OF THE MEL LED TO THIS MISTAKE.

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.