Narrative:

During cruise checklist at FL400 noticed a side hydraulic quantity at 20% and decreasing. Received cas message shortly thereafter indicating hydraulic volume a low and ran appropriate checklist. Notified ATC of situation; declared an emergency; and chose our diversion airport. Notified the owner on board of the situation and sent a message to the company as well. Completed all appropriate checklists and executed the landing. Crash; fire; rescue was standing by and surrounded the aircraft after landing on the runway. The aircraft was secured and towed into the FBO. Hydraulic fluid was found on the runway after landing and along the left side fuselage. Owners were transferred to another company aircraft that was prepared for them when we arrived at the FBO.

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Original NASA ASRS Text

Title: A CE-750 flight crew declared an emergency and diverted to a nearby airport due to low and decreasing hydraulic quantity in the A Side system.

Narrative: During cruise checklist at FL400 noticed A Side Hydraulic quantity at 20% and decreasing. Received CAS message shortly thereafter indicating Hydraulic Volume A low and ran appropriate checklist. Notified ATC of situation; declared an emergency; and chose our diversion airport. Notified the owner on board of the situation and sent a message to the company as well. Completed all appropriate checklists and executed the landing. Crash; fire; rescue was standing by and surrounded the aircraft after landing on the runway. The aircraft was secured and towed into the FBO. Hydraulic fluid was found on the runway after landing and along the left side fuselage. Owners were transferred to another company aircraft that was prepared for them when we arrived at the FBO.

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.