Narrative:

The captain called from XXX to MEL the forward flight attendant intercom system, cabin to flight deck portion. The flight attendant could hear, but could not be heard through her system. I connected the captain and I, to maintenance control in a 3-WAY phone call. The 3 of us reviewed and discussed MEL 23-4 thoroughly. Only after all of the questions and concerns were satisfied did we complete the process by maintenance issuing a tracking number and the release was amended. The captain called us back from his destination to inform us what he had discovered en route. We had all forgotten the current MEL 52-17 (flight deck door access system-keypad) that existed prior to us applying MEL 23-4. The existing MEL 52-17 clearly states that you may not also apply MEL 23-4 by referring you to MEL 23-4 with a link to that MEL. I believe we were all aware of the importance of communication within the aircraft due to security issues, thus the thorough review of MEL 23-4. However, we became too focused on the one MEL and overlooked the existing MEL. I think that if MEL 23-4 would refer to MEL 52-17, like MEL 52-17 refers to MEL 23-4, we would not have overlooked it. The MEL 23-4 was cleared before departing YYY. Hats off to the captain for catching what the three of us overlooked.

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Original NASA ASRS Text

Title: A B737 WAS DISPATCHED IN NON COMPLIANCE WITH THE FORWARD CABIN ATTENDANT FLT INTERCOM INOP IN CONFLICT WITH THE MEL.

Narrative: THE CAPT CALLED FROM XXX TO MEL THE FORWARD FLT ATTENDANT INTERCOM SYS, CABIN TO FLT DECK PORTION. THE FLT ATTENDANT COULD HEAR, BUT COULD NOT BE HEARD THROUGH HER SYS. I CONNECTED THE CAPT AND I, TO MAINT CTL IN A 3-WAY PHONE CALL. THE 3 OF US REVIEWED AND DISCUSSED MEL 23-4 THOROUGHLY. ONLY AFTER ALL OF THE QUESTIONS AND CONCERNS WERE SATISFIED DID WE COMPLETE THE PROCESS BY MAINT ISSUING A TRACKING NUMBER AND THE RELEASE WAS AMENDED. THE CAPT CALLED US BACK FROM HIS DEST TO INFORM US WHAT HE HAD DISCOVERED ENRTE. WE HAD ALL FORGOTTEN THE CURRENT MEL 52-17 (FLT DECK DOOR ACCESS SYS-KEYPAD) THAT EXISTED PRIOR TO US APPLYING MEL 23-4. THE EXISTING MEL 52-17 CLRLY STATES THAT YOU MAY NOT ALSO APPLY MEL 23-4 BY REFERRING YOU TO MEL 23-4 WITH A LINK TO THAT MEL. I BELIEVE WE WERE ALL AWARE OF THE IMPORTANCE OF COM WITHIN THE ACFT DUE TO SECURITY ISSUES, THUS THE THOROUGH REVIEW OF MEL 23-4. HOWEVER, WE BECAME TOO FOCUSED ON THE ONE MEL AND OVERLOOKED THE EXISTING MEL. I THINK THAT IF MEL 23-4 WOULD REFER TO MEL 52-17, LIKE MEL 52-17 REFERS TO MEL 23-4, WE WOULD NOT HAVE OVERLOOKED IT. THE MEL 23-4 WAS CLRED BEFORE DEPARTING YYY. HATS OFF TO THE CAPT FOR CATCHING WHAT THE THREE OF US OVERLOOKED.

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.