Narrative:

This report covers 2 flts; air carrier X ZZZ-ZZZY; nov/xa/06 and air carrier X ZZZY-ZZZ nov/xb/06 and subsequent maintenance action on nov/xz/06 regarding aircraft B757. The same crew was assigned for both flts in the same aircraft. Prior to our initial flight of air carrier X; the preflight logbook inspection revealed repeated write-ups on center right fuel pump EICAS message. Write-ups indicated that regardless of right center tank switch position or center fuel quantity; the center right fuel pump EICAS appeared. Message continued to appear intermittently even after center tank fuel exhausted and the pump turned off. Fuel load was roughly 45000 pounds with 5000 pounds being tanker fuel; including roughly 16.5 in center tank. Maintenance personnel were onboard upon arrival and were in the process of reapplying the same MEL's once again; pump low pressure lights inoperative; pump and center tank fuel pumps. This MEL combination required right center fuel pump to be deactivated. The circuit breaker was pulled and collared. I expressed my opinion to the maintenance personnel that neither of these MEL's addressed the anomaly as the pump low pressure light located in the pump switch was not being described at fault and neither was pump operation. Both the pump and its associated light were operating normal in all respects. In my opinion the anomaly was in the electrical signal being sent from the fuel system to the EICAS system for display. Their system knowledge appeared limited and they were only applying the MEL's as directed by maintenance control. Upon relaying my concerns to maintenance control; they relayed to me that maintenance control indicated this would sufficiently address the issue at hand and that the aircraft was released for flight. By this time dispatch was involved trying to interject that now all center tank fuel now had to be considered payload and that the aircraft would have to be defueled down to a total quantity of 38.6 in order to carry the load. A good catch by dispatch; thanks. When the captain arrived with the original and now new paperwork for release 2 with the MEL's applied and the new fuel load; I expressed my opinion to him that the incorrect MEL's were being applied and that neither applied to these circumstances. My 8 yrs experience on this aircraft and my 25+ yrs of aviation maintenance experience suggested to me that a wiring issue was the cause of this discrepancy and it was likely related to recent maintenance on the fuel system; perhaps the recent center tank fuel airworthiness directive. The captain talked to maintenance control and to dispatch regarding the operation. He reiterated that maintenance control was remaining firm that the action of deactivating the right center fuel pump would solve the problem and concluded the aircraft was safe for flight and appropriate for this operation regardless of the fact that in the past the same action had had no effect on the EICAS message. By this time passenger and cargo were loaded. After some additional delay; the appropriate fuel load was established and balanced in the appropriate tanks. I reluctantly acquiesced to the captain's experience and authority/authorized and upon the substantial assurance that maintenance control put in their actions. Given our limited system training these days; it's difficult to assess every system problem. En route to ZZZY; fuel had to be xferred from the center tank to the left main tank and then via the xfeed valve to the right main tank. No specific guidance is provided for this eventuality. En route to ZZZY the identical center right fuel pump EICAS message reappeared intermittently on at least 7 occasions regardless of center tank fuel quantity. By this time I thought I had convinced the captain that the MEL's were in fact misapplied to these circumstances. We spent 45+ mins reviewing aom; the communication; the MEL book and the various fault codes that would be appropriate for this circumstance and came to the conclusion that no specific fault code idented this anomaly; nor any appropriate MEL relief. The captain developed and entered an appropriate logbook entry and sent same via ACARS. Upon arrival in ZZZY we received an ACARS message to contact maintenance control regarding the write-up. The captain talked with maintenance control. The essence of that conversation relayed to me was that this maintenance control supervisor acknowledged the previous MEL attempts were and would continue to be fruitless and; that no MEL was available for relief and that maintenance action was required to fix the problem.

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Original NASA ASRS Text

Title: A B757 WAS DISPATCHED WITH THE R CTR TANK FUEL PUMP AND PRESSURE INDICATION DEFERRED INOP PER THE MEL. PROB WAS INTERMITTENT EICAS MESSAGE 'CTR R FUEL PUMP.' PUMP AND PRESSURE SWITCH OP OK.

Narrative: THIS RPT COVERS 2 FLTS; ACR X ZZZ-ZZZY; NOV/XA/06 AND ACR X ZZZY-ZZZ NOV/XB/06 AND SUBSEQUENT MAINT ACTION ON NOV/XZ/06 REGARDING ACFT B757. THE SAME CREW WAS ASSIGNED FOR BOTH FLTS IN THE SAME ACFT. PRIOR TO OUR INITIAL FLT OF ACR X; THE PREFLT LOGBOOK INSPECTION REVEALED REPEATED WRITE-UPS ON CTR R FUEL PUMP EICAS MESSAGE. WRITE-UPS INDICATED THAT REGARDLESS OF R CTR TANK SWITCH POS OR CTR FUEL QUANTITY; THE CTR R FUEL PUMP EICAS APPEARED. MESSAGE CONTINUED TO APPEAR INTERMITTENTLY EVEN AFTER CTR TANK FUEL EXHAUSTED AND THE PUMP TURNED OFF. FUEL LOAD WAS ROUGHLY 45000 LBS WITH 5000 LBS BEING TANKER FUEL; INCLUDING ROUGHLY 16.5 IN CTR TANK. MAINT PERSONNEL WERE ONBOARD UPON ARR AND WERE IN THE PROCESS OF REAPPLYING THE SAME MEL'S ONCE AGAIN; PUMP LOW PRESSURE LIGHTS INOP; PUMP AND CTR TANK FUEL PUMPS. THIS MEL COMBINATION REQUIRED R CTR FUEL PUMP TO BE DEACTIVATED. THE CIRCUIT BREAKER WAS PULLED AND COLLARED. I EXPRESSED MY OPINION TO THE MAINT PERSONNEL THAT NEITHER OF THESE MEL'S ADDRESSED THE ANOMALY AS THE PUMP LOW PRESSURE LIGHT LOCATED IN THE PUMP SWITCH WAS NOT BEING DESCRIBED AT FAULT AND NEITHER WAS PUMP OP. BOTH THE PUMP AND ITS ASSOCIATED LIGHT WERE OPERATING NORMAL IN ALL RESPECTS. IN MY OPINION THE ANOMALY WAS IN THE ELECTRICAL SIGNAL BEING SENT FROM THE FUEL SYS TO THE EICAS SYS FOR DISPLAY. THEIR SYS KNOWLEDGE APPEARED LIMITED AND THEY WERE ONLY APPLYING THE MEL'S AS DIRECTED BY MAINT CTL. UPON RELAYING MY CONCERNS TO MAINT CTL; THEY RELAYED TO ME THAT MAINT CTL INDICATED THIS WOULD SUFFICIENTLY ADDRESS THE ISSUE AT HAND AND THAT THE ACFT WAS RELEASED FOR FLT. BY THIS TIME DISPATCH WAS INVOLVED TRYING TO INTERJECT THAT NOW ALL CTR TANK FUEL NOW HAD TO BE CONSIDERED PAYLOAD AND THAT THE ACFT WOULD HAVE TO BE DEFUELED DOWN TO A TOTAL QUANTITY OF 38.6 IN ORDER TO CARRY THE LOAD. A GOOD CATCH BY DISPATCH; THANKS. WHEN THE CAPT ARRIVED WITH THE ORIGINAL AND NOW NEW PAPERWORK FOR RELEASE 2 WITH THE MEL'S APPLIED AND THE NEW FUEL LOAD; I EXPRESSED MY OPINION TO HIM THAT THE INCORRECT MEL'S WERE BEING APPLIED AND THAT NEITHER APPLIED TO THESE CIRCUMSTANCES. MY 8 YRS EXPERIENCE ON THIS ACFT AND MY 25+ YRS OF AVIATION MAINT EXPERIENCE SUGGESTED TO ME THAT A WIRING ISSUE WAS THE CAUSE OF THIS DISCREPANCY AND IT WAS LIKELY RELATED TO RECENT MAINT ON THE FUEL SYS; PERHAPS THE RECENT CTR TANK FUEL AIRWORTHINESS DIRECTIVE. THE CAPT TALKED TO MAINT CTL AND TO DISPATCH REGARDING THE OP. HE REITERATED THAT MAINT CTL WAS REMAINING FIRM THAT THE ACTION OF DEACTIVATING THE R CTR FUEL PUMP WOULD SOLVE THE PROB AND CONCLUDED THE ACFT WAS SAFE FOR FLT AND APPROPRIATE FOR THIS OP REGARDLESS OF THE FACT THAT IN THE PAST THE SAME ACTION HAD HAD NO EFFECT ON THE EICAS MESSAGE. BY THIS TIME PAX AND CARGO WERE LOADED. AFTER SOME ADDITIONAL DELAY; THE APPROPRIATE FUEL LOAD WAS ESTABLISHED AND BALANCED IN THE APPROPRIATE TANKS. I RELUCTANTLY ACQUIESCED TO THE CAPT'S EXPERIENCE AND AUTH AND UPON THE SUBSTANTIAL ASSURANCE THAT MAINT CTL PUT IN THEIR ACTIONS. GIVEN OUR LIMITED SYS TRAINING THESE DAYS; IT'S DIFFICULT TO ASSESS EVERY SYS PROB. ENRTE TO ZZZY; FUEL HAD TO BE XFERRED FROM THE CTR TANK TO THE L MAIN TANK AND THEN VIA THE XFEED VALVE TO THE R MAIN TANK. NO SPECIFIC GUIDANCE IS PROVIDED FOR THIS EVENTUALITY. ENRTE TO ZZZY THE IDENTICAL CTR R FUEL PUMP EICAS MESSAGE REAPPEARED INTERMITTENTLY ON AT LEAST 7 OCCASIONS REGARDLESS OF CTR TANK FUEL QUANTITY. BY THIS TIME I THOUGHT I HAD CONVINCED THE CAPT THAT THE MEL'S WERE IN FACT MISAPPLIED TO THESE CIRCUMSTANCES. WE SPENT 45+ MINS REVIEWING AOM; THE COM; THE MEL BOOK AND THE VARIOUS FAULT CODES THAT WOULD BE APPROPRIATE FOR THIS CIRCUMSTANCE AND CAME TO THE CONCLUSION THAT NO SPECIFIC FAULT CODE IDENTED THIS ANOMALY; NOR ANY APPROPRIATE MEL RELIEF. THE CAPT DEVELOPED AND ENTERED AN APPROPRIATE LOGBOOK ENTRY AND SENT SAME VIA ACARS. UPON ARR IN ZZZY WE RECEIVED AN ACARS MESSAGE TO CONTACT MAINT CTL REGARDING THE WRITE-UP. THE CAPT TALKED WITH MAINT CTL. THE ESSENCE OF THAT CONVERSATION RELAYED TO ME WAS THAT THIS MAINT CTL SUPVR ACKNOWLEDGED THE PREVIOUS MEL ATTEMPTS WERE AND WOULD CONTINUE TO BE FRUITLESS AND; THAT NO MEL WAS AVAILABLE FOR RELIEF AND THAT MAINT ACTION WAS REQUIRED TO FIX THE PROB.

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.