Cessna Citation Sovereign (C680)
Flight Crew Air Transport Pilot (ATP)
Workload
Aircraft Equipment Problem Critical; Ground Excursion Runway
Flight Crew Diverted; Flight Crew Landed in Emergency Condition; General Declared Emergency
Aircraft
Shortly after landing gear retraction; the amber CAS message Hydraulic Volume Low illuminated. The EICAS indicator showed 0 volume in the hydraulic reservoir. We climbed to a safe altitude and ran the checklist for the malfunction and continued toward the mainland to determine a suitable landing site. The company was contacted regarding the problem and requested we land at an isolated field. We determined a larger airport had more suitable runways and informed ATC we would be making an emergency landing there. Based on the landing numbers per the checklist criteria; Runway XX was suitable. We rehearsed the landing sequence prior to touchdown to ensure we were coordinated in our efforts. Upon touchdown; the emergency braking system was applied; but seemed to have little effect. The airplane coasted to a stop.  All passengers and crew were OK.
A CE680 EICAS alerted HYDRAULIC VOLUME LOW after landing gear retraction so the flight diverted and after landing when the aircraft's braking systems failed; the aircraft rolled safely to a stop.