An md-11 was dispatched with the left transfer valve inoperative; and experienced multiple fuel anom...

Attributes
ACN	788794
Time
Date	200805
Local Time Of Day	1201 To 1800
Place
Locale Reference	airport : zzz.airport
State Reference	US
Altitude	msl single value : 10000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tracon : zzz.tracon
Operator	common carrier : air carrier
Make Model Name	MD-11
Operating Under FAR Part	Part 121
Flight Phase	descent : approach
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Experience	flight time last 90 days : 26 flight time total : 7500 flight time type : 26
ASRS Report	788794
Events
Anomaly	aircraft equipment problem : less severe
Independent Detector	other flight crewa
Resolutory Action	flight crew : overcame equipment problem
Supplementary
Problem Areas	Aircraft Maintenance Human Performance
Primary Problem	Ambiguous

Narrative:

On this particular flight; we had the left xfer valve deferred on the fuel system; and were operating the fuel system in manual per MEL procedures. During the flight we had numerous faults with the left tank on the fuel system; such as: tip tank trapped fuel; left tank quantity indicator; left tip tank low; etc. These all self-cleared. On descent in the ZZZ area; we received fuel imbal. Approximately 5 mins before that; I had checked the quantities and they were within tolerance of balanced. The fuel imbal alert did not appear until the left tank showed 5000 pounds less than center tank and right tank. I continued to fly while the captain re-balanced the fuel. This amount was twice the value of our limitation tolerance. When this alert appeared; I did disconnect the autoplt and the aircraft seemed slightly right wing heavy with zero trim on aileron and rudder. I did this because we wanted to confirm the quantity indicators accuracy by feel. We balanced the fuel manually; and made an uneventful approach and landing as scheduled in ZZZ. Perhaps maintenance should have looked at the fuel system more closely before they deferred the left fuel xfer valve or researched other problems with the fuel system history. The aircraft seemed to have a lot of problems with the fuel system.

Original NASA ASRS Text

Title: AN MD-11 WAS DISPATCHED WITH THE LEFT TRANSFER VALVE INOP; AND EXPERIENCED MULTIPLE FUEL ANOMALIES INCLUDING IMBALANCE.

Narrative: ON THIS PARTICULAR FLT; WE HAD THE L XFER VALVE DEFERRED ON THE FUEL SYS; AND WERE OPERATING THE FUEL SYS IN MANUAL PER MEL PROCS. DURING THE FLT WE HAD NUMEROUS FAULTS WITH THE L TANK ON THE FUEL SYS; SUCH AS: TIP TANK TRAPPED FUEL; L TANK QUANTITY INDICATOR; L TIP TANK LOW; ETC. THESE ALL SELF-CLRED. ON DSCNT IN THE ZZZ AREA; WE RECEIVED FUEL IMBAL. APPROX 5 MINS BEFORE THAT; I HAD CHKED THE QUANTITIES AND THEY WERE WITHIN TOLERANCE OF BALANCED. THE FUEL IMBAL ALERT DID NOT APPEAR UNTIL THE L TANK SHOWED 5000 LBS LESS THAN CTR TANK AND R TANK. I CONTINUED TO FLY WHILE THE CAPT RE-BALANCED THE FUEL. THIS AMOUNT WAS TWICE THE VALUE OF OUR LIMITATION TOLERANCE. WHEN THIS ALERT APPEARED; I DID DISCONNECT THE AUTOPLT AND THE ACFT SEEMED SLIGHTLY R WING HVY WITH ZERO TRIM ON AILERON AND RUDDER. I DID THIS BECAUSE WE WANTED TO CONFIRM THE QUANTITY INDICATORS ACCURACY BY FEEL. WE BALANCED THE FUEL MANUALLY; AND MADE AN UNEVENTFUL APCH AND LNDG AS SCHEDULED IN ZZZ. PERHAPS MAINT SHOULD HAVE LOOKED AT THE FUEL SYS MORE CLOSELY BEFORE THEY DEFERRED THE L FUEL XFER VALVE OR RESEARCHED OTHER PROBS WITH THE FUEL SYS HISTORY. THE ACFT SEEMED TO HAVE A LOT OF PROBS WITH THE FUEL SYS.

Data retrieved from NASA's ASRS site as of May 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.

An md-11 was dispatched with the left transfer valve inoperative; and experienced multiple fuel anomalies including imbalance.