B757 flight crew reports departing with multiple mels concerning inoperative fuel gauges and discove...

Narrative:

Aircraft had 3 MEL's 28-xx-X; 28-xx-Y; 28-xx-Z. There were other issues with the aircraft involving an autopilot and auto throttle that required maintenance to be aboard the aircraft. All the deferrals required long; convoluted language to review so I decided to query the maintenance personnel if all procedures where completed via the MEL. The fuel load was approximately 14.2 in the mains and 8.0 in the center. After reviewing all MEL procedures more than once; we decided that the aircraft was good to go for normal operation per MEL procedures 28-xx-Y. The hidden problem was MEL 28-xx-X that the flight could not operate with the cross feed open. This conflicted with the previous MEL since fuel was in the center tank. Per the center fuel pump inop procedures we took off and fuel was used at a normal point until depleted prior to ZZZ. No other legs after that required fuel in the center tank. Our flight release had no notation the crossfeed valve was restricted. I also operated on the best knowledge that we were being dispatched to ZZZ tankering fuel to ZZZ precluding the need to uplift fuel in ZZZ and that the maintenance personnel provided me information knowing they knew that fuel was in the center tank. These multiple MEL's were convoluted and confusing at best. Our previous flight that day with a flip to a night operation could also been a contributing factor in the form of fatigue.

Original NASA ASRS Text

Title: B757 flight crew reports departing with multiple MELs concerning inoperative fuel gauges and discovers; once airborne; that they may have had conflicting requirements.

Narrative: Aircraft had 3 MEL's 28-XX-X; 28-XX-Y; 28-XX-Z. There were other issues with the aircraft involving an autopilot and auto throttle that required maintenance to be aboard the aircraft. All the deferrals required long; convoluted language to review so I decided to query the maintenance personnel if all procedures where completed via the MEL. The fuel load was approximately 14.2 in the mains and 8.0 in the center. After reviewing all MEL procedures more than once; we decided that the aircraft was good to go for normal operation per MEL procedures 28-XX-Y. The hidden problem was MEL 28-XX-X that the flight could not operate with the cross feed open. This conflicted with the previous MEL since fuel was in the center tank. Per the center fuel pump inop procedures we took off and fuel was used at a normal point until depleted prior to ZZZ. No other legs after that required fuel in the center tank. Our flight release had no notation the crossfeed valve was restricted. I also operated on the best knowledge that we were being dispatched to ZZZ tankering fuel to ZZZ precluding the need to uplift fuel in ZZZ and that the maintenance personnel provided me information knowing they knew that fuel was in the center tank. These multiple MEL's were convoluted and confusing at best. Our previous flight that day with a flip to a night operation could also been a contributing factor in the form of fatigue.

Data retrieved from NASA's ASRS site 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.

Attributes
ACN	1227690
Time
Date	201412
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	IMC
Light	Night
Aircraft 1
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	Parked
Route In Use	Other Controlled
Component
Aircraft Component	Fuel Quantity-Pressure Indication
Person 1
Function	First Officer Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Person 2
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Less Severe Deviation - Procedural MEL Deviation - Procedural Published Material / Policy

B757 flight crew reports departing with multiple mels concerning inoperative fuel gauges and discovers; once airborne; that they may have had conflicting requirements.