Narrative:

On jan/fri/04, the autoplt was MEL'ed. I reviewed the MEL procedure for autoplt to confirm compliance with it. The broken part of the autoplt was merely the vertical speed select knob. In accordance with autoplt MEL the whole unit was disabled by pulling and collaring the circuit breaker. On jan/sat/04, the autoplt was reinstalled by maintenance and I performed the preflight inspection on it, discovering that the unit was not fixed properly rendering all autoplt functions inoperative. Maintenance was notified but they simply tried to MEL it again. I then discovered a problem: an MEL (altitude alerter, requiring the altitude hold function of the autoplt) that had been complied with before the jan/fri/04, was not being complied with after jan/fri/04, because the autoplt was collared off, disabling the required altitude hold function of the autoplt. I refused to fly the aircraft. Maintenance responded by saying that all crews had flown the aircraft in this confign last week. I was one of those crew members and was surprised that I had made that mistake, as I am a thorough person. Upon careful review of my mistake I found the following contributing factors: the MEL made reference that autoplt altitude hold must work when there is no altitude alerter, but did not reference that altitude alerter must work when altitude hold is under MEL. Because I was in compliance with the altitude alerter prior to the autoplt problem and no reference was made of the altitude alerter in the autoplt MEL, I missed the connection. Solution: the MEL should be rewritten with proper xrefs so there is no confusion in the future.

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Original NASA ASRS Text

Title: A BEECH 1900 WAS DISPATCHED IN NON COMPLIANCE WITH THE ALT ALERTER INOP AND THE ALT HOLD ALSO INOP BOTH DEFERRED PER THE MEL. ONE SYS MUST BE OPERATIVE TO MEET MEL LIMITS.

Narrative: ON JAN/FRI/04, THE AUTOPLT WAS MEL'ED. I REVIEWED THE MEL PROC FOR AUTOPLT TO CONFIRM COMPLIANCE WITH IT. THE BROKEN PART OF THE AUTOPLT WAS MERELY THE VERT SPD SELECT KNOB. IN ACCORDANCE WITH AUTOPLT MEL THE WHOLE UNIT WAS DISABLED BY PULLING AND COLLARING THE CIRCUIT BREAKER. ON JAN/SAT/04, THE AUTOPLT WAS REINSTALLED BY MAINT AND I PERFORMED THE PREFLT INSPECTION ON IT, DISCOVERING THAT THE UNIT WAS NOT FIXED PROPERLY RENDERING ALL AUTOPLT FUNCTIONS INOP. MAINT WAS NOTIFIED BUT THEY SIMPLY TRIED TO MEL IT AGAIN. I THEN DISCOVERED A PROB: AN MEL (ALT ALERTER, REQUIRING THE ALT HOLD FUNCTION OF THE AUTOPLT) THAT HAD BEEN COMPLIED WITH BEFORE THE JAN/FRI/04, WAS NOT BEING COMPLIED WITH AFTER JAN/FRI/04, BECAUSE THE AUTOPLT WAS COLLARED OFF, DISABLING THE REQUIRED ALT HOLD FUNCTION OF THE AUTOPLT. I REFUSED TO FLY THE ACFT. MAINT RESPONDED BY SAYING THAT ALL CREWS HAD FLOWN THE ACFT IN THIS CONFIGN LAST WK. I WAS ONE OF THOSE CREW MEMBERS AND WAS SURPRISED THAT I HAD MADE THAT MISTAKE, AS I AM A THOROUGH PERSON. UPON CAREFUL REVIEW OF MY MISTAKE I FOUND THE FOLLOWING CONTRIBUTING FACTORS: THE MEL MADE REF THAT AUTOPLT ALT HOLD MUST WORK WHEN THERE IS NO ALT ALERTER, BUT DID NOT REF THAT ALT ALERTER MUST WORK WHEN ALT HOLD IS UNDER MEL. BECAUSE I WAS IN COMPLIANCE WITH THE ALT ALERTER PRIOR TO THE AUTOPLT PROB AND NO REF WAS MADE OF THE ALT ALERTER IN THE AUTOPLT MEL, I MISSED THE CONNECTION. SOLUTION: THE MEL SHOULD BE REWRITTEN WITH PROPER XREFS SO THERE IS NO CONFUSION IN THE FUTURE.

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.