Narrative:

During cruise flight approximately 1.5 hours [into flight]; FL340; observed 'RF' indication on center hydraulic system; started clock and determined constant decreasing quantity. Declared emergency [and] diverted to [nearest suitable airport]. Post flight confirmed center hydraulic fluid leak.

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Original NASA ASRS Text

Title: B767-300ER Captain reported inflight loss of center hydraulic system. Flight diverted to nearest suitable airport.

Narrative: During cruise flight approximately 1.5 hours [into flight]; FL340; observed 'RF' indication on center hydraulic system; started clock and determined constant decreasing quantity. Declared emergency [and] diverted to [nearest suitable airport]. Post flight confirmed center hydraulic fluid leak.

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.