Narrative:

At FL410 enroute after reaching cruise altitude. EICAS indicated a hydraulic qty <16%. Thus we declared an emergency and complied with checklist. As a result we made a flaps 15 landing after blowing landing gear down and using emergency brake. We stopped aircraft on runway and were towed off. No injuries and no damage.

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Original NASA ASRS Text

Title: A Citation X's hydraulic system A fluid indicated a low level at cruise altitude; an emergency was declared with a subsequent diversion to a nearby airport.

Narrative: At FL410 enroute after reaching cruise altitude. EICAS indicated a HYD QTY <16%. Thus we declared an emergency and complied with checklist. As a result we made a Flaps 15 landing after blowing landing gear down and using emergency brake. We stopped aircraft on runway and were towed off. No injuries and no damage.

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.