Narrative:

Flight den-sat had been previously MEL'ed regarding the service interphone chime in the cockpit. During the flight, out of curiosity, it was discovered the original MEL #1, was in error and should have related to MEL #2. Oddly enough, the inoperative chime still could have been interpreted for the original write-up due to poorly written MEL #1. Flight deck to cabin, cabin to cabin, cabin to flight deck interphone system may be inoperative provided alternate, normal, and emergency procedures are established and used and the PA system operates normally. This seemed to suffice until we made ourselves aware of MEL #2. This MEL still under service interphone system relates to the alerting system. It reads that the visual signal may be inoperative in the cockpit saying nothing about the chime. So comes the confusion. The system itself could be inoperative under MEL #2 but a component within the system (i.e., an alerting chime) could not. All being said it was concluded that the chime could not be written off as an MEL and we notified the company upon landing in ksat. This started them to rethinking the placard, eventually grounding the aircraft until the repair was made, ending the dispute. Since I was part of the flight crew interpreting the MEL on the conservative side, I feel possibly at risk from a poorly written assessment of the cockpit chime dealing with the interphone.

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Original NASA ASRS Text

Title: FLC ACR MLG ACFT INADVERTENTLY OPERATED THE ACFT IN NON COMPLIANCE WITH AN ACFT MEL PROVISIONS.

Narrative: FLT DEN-SAT HAD BEEN PREVIOUSLY MEL'ED REGARDING THE SVC INTERPHONE CHIME IN THE COCKPIT. DURING THE FLT, OUT OF CURIOSITY, IT WAS DISCOVERED THE ORIGINAL MEL #1, WAS IN ERROR AND SHOULD HAVE RELATED TO MEL #2. ODDLY ENOUGH, THE INOP CHIME STILL COULD HAVE BEEN INTERPRETED FOR THE ORIGINAL WRITE-UP DUE TO POORLY WRITTEN MEL #1. FLT DECK TO CABIN, CABIN TO CABIN, CABIN TO FLT DECK INTERPHONE SYS MAY BE INOP PROVIDED ALTERNATE, NORMAL, AND EMER PROCS ARE ESTABLISHED AND USED AND THE PA SYS OPERATES NORMALLY. THIS SEEMED TO SUFFICE UNTIL WE MADE OURSELVES AWARE OF MEL #2. THIS MEL STILL UNDER SVC INTERPHONE SYS RELATES TO THE ALERTING SYS. IT READS THAT THE VISUAL SIGNAL MAY BE INOP IN THE COCKPIT SAYING NOTHING ABOUT THE CHIME. SO COMES THE CONFUSION. THE SYS ITSELF COULD BE INOP UNDER MEL #2 BUT A COMPONENT WITHIN THE SYS (I.E., AN ALERTING CHIME) COULD NOT. ALL BEING SAID IT WAS CONCLUDED THAT THE CHIME COULD NOT BE WRITTEN OFF AS AN MEL AND WE NOTIFIED THE COMPANY UPON LNDG IN KSAT. THIS STARTED THEM TO RETHINKING THE PLACARD, EVENTUALLY GNDING THE ACFT UNTIL THE REPAIR WAS MADE, ENDING THE DISPUTE. SINCE I WAS PART OF THE FLC INTERPRETING THE MEL ON THE CONSERVATIVE SIDE, I FEEL POSSIBLY AT RISK FROM A POORLY WRITTEN ASSESSMENT OF THE COCKPIT CHIME DEALING WITH THE INTERPHONE.

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.