Narrative:

While on rest break; the other relief pilot and I were called up to the cockpit by the captain following 'blanking' of the left main fuel tank quantity indicator. After consultation with checklists; dispatch; maintenance control; MEL (for reference only); and applicable landing data; the captain elected to return to departure airport; declare an in flight emergency and land overweight.

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Original NASA ASRS Text

Title: B777 Relief Pilots are informed one hour into flight by the operating crew that they have lost fuel quantity indication in the left main tank and are returning to the departure airport. An uneventful overweight landing ensues.

Narrative: While on rest break; the other Relief Pilot and I were called up to the cockpit by the Captain following 'blanking' of the left main fuel tank quantity indicator. After consultation with checklists; Dispatch; Maintenance Control; MEL (for reference only); and applicable landing data; the Captain elected to return to departure airport; declare an in flight emergency and land overweight.

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.