Narrative:

We were dispatched with the main tank 1 aft fuel pump inoperative. This drove several non-normal requirements. One of those requirements was to have a minimum of 17;000 pounds of fuel in the center tank for takeoff. Once the fuel was placed into the center tank; it began to decrease from 17.0 to 16.3 with the center override pumps off. Also; by following standard operating procedures to configure the fuel panel prior to accomplishing the before start checklist; the center tank fuel would be below the 17.0 for takeoff given taxi and apu fuel burn. After takeoff; the first officer advised me that the center tank fuel was 15.7 at the start of the takeoff roll. It is unknown why we burned 3.2 in a 12 minute taxi out. Had I known that we were below the 17.0 at powerup; I would have aborted the takeoff. I believe that the first officer thought the anomaly was due to inaccuracies in the system and that we did have the 17.0 onboard. The MEL item card needs to be rewritten to clarify flight crew fuel panel procedures to keep the center override pumps off until takeoff or require the center tank fuel to be fueled to accommodate taxi fuel and apu burn. The MEL card caused confusion in the cockpit about how to configure the fuel panel. The card needs to be rewritten to clarify exactly the pump and crossfeed configurations required. Fuel imbalance during climbout (we got a fuel imbalance EICAS message). There was an imbalance of about 4000 pounds between main tank 1 and main tank 4 with the center tank override pumps on and 1 and 4 crossfeeds open. Fuel in all main tanks was symmetrical at takeoff. We believe that this should not have happened since all engines should have been feeding off the center tank. Premature center tank low message. Also during climbout with 4 degrees anu; we got the EICAS messages to turn off the center tank override pumps with 6.8 remaining in the tank. Shortly thereafter; with 4.5 in the center tank; we got an EICAS message that the center right override pump had failed. We accomplished the irregular procedure. We contacted maintenance control through dispatch and advised them of these anomalies. We were concerned because the deferral of the main tank 1 aft pump requires that the following operate normally: 1. Remaining 7 fuel pumps 2. Main tanks 1 and 4 transfer valves 3. Both center tank pumps. Upon arrival at ZZZZ; a mechanic called me on the flight interphone and wanted to know why we were operating with center tank fuel. I had to explain to him the requirements of the fuel pump deferral. Cycling circuit breakers seems to be an inadequate fix? I later checked the computer maintenance records and saw that the corrective action by maintenance was to cycle some circuit breakers and clear our write ups. It seems to me that there was never an understanding by maintenance as to what was causing the problems. This is very troubling in light of the operational equipment requirements outlined above. Some circuit breakers were cycled and the aircraft was dispatched to fly from ZZZZ back to the USA. This flight was complicated by the following: 1) fuel pump deferral with numerous additional flight planning and crew requirements. 2)onfusing and incomplete MEL item. 3) difficulty in transferring the fuel into the center tank for unknown reason. 4) routing around a typhoon. 5) center tank fuel decreasing for unknown reason. 6) delay in fueling due to airport requirements to have fire truck present. 7) last minute ATC reroute just prior to taking the runway. 8) subsequent lengthy en route reroute during climbout. 9) less than required center tank fuel at takeoff. 10) fuel imbalance after takeoff. 11) center tank low fuel message coming on 3000 pounds early. 12) center tank pump failure. 13) worse than forecast weather at ZZZZ with unforecast windshear advisories in effect. We made a normal landing in ZZZZ.

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Original NASA ASRS Text

Title: A B747-400 Captain details numerous operational problems associated with the operational MEL requirements for an inoperative left main tank boost pump.

Narrative: We were dispatched with the MAIN TANK 1 AFT fuel pump inoperative. This drove several non-normal requirements. One of those requirements was to have a minimum of 17;000 pounds of fuel in the center tank for takeoff. Once the fuel was placed into the center tank; it began to decrease from 17.0 to 16.3 with the center override pumps OFF. Also; by following standard operating procedures to configure the fuel panel prior to accomplishing the BEFORE START CHECKLIST; the center tank fuel would be below the 17.0 for takeoff given taxi and apu fuel burn. After takeoff; the First Officer advised me that the center tank fuel was 15.7 at the start of the takeoff roll. It is unknown why we burned 3.2 in a 12 minute taxi out. Had I known that we were below the 17.0 at powerup; I would have aborted the takeoff. I believe that the First Officer thought the anomaly was due to inaccuracies in the system and that we did have the 17.0 onboard. The MEL item card needs to be rewritten to clarify flight crew fuel panel procedures to keep the center override pumps off until takeoff or require the center tank fuel to be fueled to accommodate taxi fuel and apu burn. The MEL card caused confusion in the cockpit about how to configure the fuel panel. The card needs to be rewritten to clarify exactly the pump and crossfeed configurations required. Fuel imbalance during climbout (we got a FUEL IMBALANCE EICAS message). There was an imbalance of about 4000 pounds between MAIN TANK 1 AND MAIN TANK 4 with the center tank override pumps on and 1 and 4 crossfeeds open. Fuel in all main tanks was symmetrical at takeoff. We believe that this should not have happened since all engines should have been feeding off the center tank. Premature center tank low message. Also during climbout with 4 degrees ANU; we got the EICAS messages to turn off the center tank override pumps with 6.8 remaining in the tank. Shortly thereafter; with 4.5 in the center tank; we got an EICAS message that the center right override pump had failed. We accomplished the irregular procedure. We contacted Maintenance Control through Dispatch and advised them of these anomalies. We were concerned because the deferral of the MAIN TANK 1 AFT pump requires that the following operate normally: 1. remaining 7 fuel pumps 2. main tanks 1 and 4 transfer valves 3. both center tank pumps. Upon arrival at ZZZZ; a Mechanic called me on the flight interphone and wanted to know why we were operating with center tank fuel. I had to explain to him the requirements of the fuel pump deferral. Cycling circuit breakers seems to be an inadequate fix? I later checked the computer maintenance records and saw that the corrective action by Maintenance was to cycle some circuit breakers and clear our write ups. It seems to me that there was never an understanding by Maintenance as to what was causing the problems. This is very troubling in light of the operational equipment requirements outlined above. Some circuit breakers were cycled and the aircraft was dispatched to fly from ZZZZ back to the USA. This flight was complicated by the following: 1) Fuel pump deferral with numerous additional flight planning and crew requirements. 2)onfusing and incomplete MEL item. 3) Difficulty in transferring the fuel into the center tank for unknown reason. 4) Routing around a typhoon. 5) Center tank fuel decreasing for unknown reason. 6) Delay in fueling due to airport requirements to have fire truck present. 7) Last minute ATC reroute just prior to taking the runway. 8) Subsequent lengthy en route reroute during climbout. 9) Less than required center tank fuel at takeoff. 10) Fuel imbalance after takeoff. 11) Center tank low fuel message coming on 3000 pounds early. 12) Center tank pump failure. 13) Worse than forecast weather at ZZZZ with unforecast windshear advisories in effect. We made a normal landing in ZZZZ.

Data retrieved from NASA's ASRS site as of April 2012 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.