Narrative:

This B747 aircraft has a chronic unwanted fuel transfer problem in flight. It's been written up 10+ times in the last three months. Each time maintenance just does a test of the fuel quantity indicating system (fqis) and signs it off; or else finds something convenient and easy to defer so they can keep the airplane moving. Discrepancy noted in october 2013 describes the problem exactly. Prior to reaching a tank-to-engine configuration; fuel is disappearing from main tank #1 when it shouldn't. Also; prior to reaching tank-to-engine; but after depleting the center tank; main tank #3 decreases faster than main tank #2. This all happens with the engine fuel flows matched perfectly. The tanks have been dripped to confirm the accuracy of the cockpit gauges. There is nothing else this could be but an unwanted transfer or a leak. After this flight; a mechanic told me that a crew needs to refuse this airplane so they can get it into the hangar and do a thorough troubleshooting job. But here's the problem with that... The maintenance history presented to the crew during flight planning only shows the last twenty items of history. This list is almost completely populated with cabin defects (reading lights; video monitors; etc.); so it masks the real problems with the airplane. There is no way for a crew to know that there is three months of history on a fuel system malfunction unless they remember the airplane from a previous flight and go looking for it -- which is how I stumbled across it. The maintenance history presented to the crew really needs to be stripped of non-essential items so the crew can focus on actual system malfunctions. There are not a lot of places to land in the middle of the ocean. Somebody needs to fix the fuel system problems in this airplane before they lead to something bigger.

Related reports:

Google
 

Original NASA ASRS Text

Title: A First Officer reports that a company B747 aircraft has chronic unwanted fuel transfer problems in flight that have been written up 10+ times in the last three months. Fuel is disappearing from Main Tank #1 when it should not be; and after depleting the Center Tank; Main tank #3 decreases faster than Main tank #2.

Narrative: This B747 aircraft has a chronic unwanted fuel transfer problem in flight. It's been written up 10+ times in the last three months. Each time Maintenance just does a test of the Fuel Quantity Indicating System (FQIS) and signs it off; or else finds something convenient and easy to defer so they can keep the airplane moving. Discrepancy noted in October 2013 describes the problem exactly. Prior to reaching a Tank-to-Engine Configuration; fuel is disappearing from Main tank #1 when it shouldn't. Also; prior to reaching Tank-to-Engine; but after depleting the Center tank; Main tank #3 decreases faster than Main tank #2. This all happens with the engine fuel flows matched perfectly. The tanks have been dripped to confirm the accuracy of the cockpit gauges. There is nothing else this could be but an unwanted transfer or a leak. After this flight; a Mechanic told me that a crew needs to refuse this airplane so they can get it into the Hangar and do a thorough troubleshooting job. But here's the problem with that... The maintenance history presented to the crew during flight planning only shows the last twenty items of history. This list is almost completely populated with cabin defects (reading lights; video monitors; etc.); so it masks the real problems with the airplane. There is no way for a crew to know that there is three months of history on a fuel system malfunction unless they remember the airplane from a previous flight and go looking for it -- which is how I stumbled across it. The maintenance history presented to the crew really needs to be stripped of non-essential items so the crew can focus on actual system malfunctions. There are not a lot of places to land in the middle of the Ocean. Somebody needs to fix the fuel system problems in this airplane before they lead to something bigger.

Data retrieved from NASA's ASRS site as of July 2013 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.