Narrative:

Received right hydraulic quantity message. Checked quantity/confirmed condition (fluid was down to stand pipe). Completed procedure (turned off right engine and electrical pumps). Declared emergency with center; notified dispatch; requested crash fire rescue equipment at ZZZZ. Uneventful landing. Maintenance personnel arrived next day and replaced blown o-ring.

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Original NASA ASRS Text

Title: B757-200 FLT CREW HAS EICAS 'R HYD QUANTITY' MESSAGE; COMPLETES QRH PROCS. DECLARES EMER; DIVERTS FOR LNDG.

Narrative: RECEIVED R HYD QUANTITY MESSAGE. CHKED QUANTITY/CONFIRMED CONDITION (FLUID WAS DOWN TO STAND PIPE). COMPLETED PROC (TURNED OFF R ENG AND ELECTRICAL PUMPS). DECLARED EMER WITH CTR; NOTIFIED DISPATCH; REQUESTED CFR AT ZZZZ. UNEVENTFUL LNDG. MAINT PERSONNEL ARRIVED NEXT DAY AND REPLACED BLOWN O-RING.

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