Service difficulty report · Compensator · Boeing 737990ER

Difficulty date
December 28, 2020
Submitted
December 30, 2020
Operation
Air carrier
Aircraft
N481AS
Make and model
Boeing 737990ER
Aircraft serial
44106
Aircraft time
20,434 hours, 6,523 cycles
Part
Compensator
Part number
2020202
Part serial
17137
Condition
Malfunctioned
Location
Lt Wing
Part time
20,434 hours, 6,523 cycles
Stage of operation
TO
How discovered
O
Nature of condition
J
Precautionary procedure
O

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

ON TAKE-OFF ROTATION LEFT MAIN FUEL INDICATIONS SLOWLY DROPPED TO 7370 POUNDS WITH FUEL IN CENTER TANK ALL 6 FUEL PUMPS ON AND CROSSFEED CLOSED. MAX IMBALANCE WAS 1200 POUNDS. AFTER CENTER TANK FUEL WAS USED WE USED FUEL OUT OF RIGHT TANK TO SET IMBALANCE TO 300 POUNDS. GROUNDED - YES. REMOVED DEBRIS FROM NR 1 FUEL TANK AT NR 1 FQIS COMPENSATOR MOUNTING LOCATION. WHILE IN THE NR 1 MAIN FUEL TANK AT THIS LOCATION REMOVED AND REPLACED NR 1 FQIS COMPENSATOR AND TANK UNIT NR 1 PRECAUTIONARY, REF B737-900 AMM 28-41-21/401. NR 1 FQIS SYSTEM TEST GOOD, REF AMM TASK 28-41-00-730-801. FOR INSPECTION REQUIREMENTS, DEACTIVATION AND LEAK CHECK, REF TANK ENTRY PERMIT 78528000-LINE. REF LOG PAGE NR 60010401 FOR OP DEFERRAL, REF LOG PAGE NR 60010404 FOR FUEL IMBALANCE EXCEEDANCE CONDITIONAL INSPECTION.