What was found
ON LANDING ROLL, HAD A COMPLETE LOSS OF SYSTEM HYD FLUID AND EMERGENCY BRAKE WAS USED, AIRCRAFT HYDROPLANED BUT STOPPED SAFELY, NO VISIBLE DAMAGE TO AIRCRAFT. REPLACED ORING PLUG, ON "A" HYDRAULIC MANIFOLD, AND OPERATIONALLY TESTED, BLED SYSTEM AND LEAK CHECKED, IAW CE750 M/M CP: 29-10-01.