Evidence of a possible leak in the left main tank of a B777 caused the flight crew to divert to a ne...

Attributes
ACN	825721
Time
Date	200902
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZ.Airport
State Reference	US
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Make Model Name	B777 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Flight Phase	Cruise
Flight Plan	IFR
Component
Aircraft Component	Fuel Tank
Person 1
Function	Captain Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP) Flight Crew Flight Engineer
Experience	Flight Crew Last 90 Days 150 Flight Crew Total 19000 Flight Crew Type 1700
Events
Anomaly	Aircraft Equipment Problem Critical

Narrative:

A fuel imbalance was noted of 1;000 pounds left main tank low. Total fuel on board 40;000 pounds. Fuel was balanced but left main tank quantity continued to decrease. Appropriate checklists and visual check of left wing/engine area accomplished. No visual indication of leak. A decision was made to make a precautionary landing at ZZZ. Dispatch advised ZZZ airport closed. Emergency was declared; clearance received via controller pilot datalink communications (cpdlc). ZZZ tower closed; visual approach made to runway 12 using pilot controlled lighting. Arff equipment standing by runway. Normal landing. Upon clearing runway; left engine shut down and fire handle pulled as a precaution. Evidence of fuel leak from left engine discovered at gate.

Original NASA ASRS Text

Title: Evidence of a possible leak in the left main tank of a B777 caused the flight crew to divert to a nearby oceanic airport for maintenance examination.

Narrative: A fuel imbalance was noted of 1;000 LBS left main tank low. Total fuel on board 40;000 LBS. Fuel was balanced but left main tank quantity continued to decrease. Appropriate checklists and visual check of left wing/engine area accomplished. No visual indication of leak. A decision was made to make a precautionary landing at ZZZ. Dispatch advised ZZZ Airport closed. Emergency was declared; clearance received via Controller Pilot Datalink Communications (CPDLC). ZZZ Tower closed; visual approach made to Runway 12 using pilot controlled lighting. ARFF equipment standing by runway. Normal landing. Upon clearing runway; left engine shut down and fire handle pulled as a precaution. Evidence of fuel leak from left engine discovered at gate.

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.