What was found
(CAN) DURING FLIGHT, THE NR 1 HYDRAULIC SYSTEM FLUID LEVEL DEPLETED TO ZERO. AIRPORT CFR SERVICES WERE PLACED ON STANDBY FOR THE LANDING WHICH WAS UNEVENTFUL. SUBSEQUENT MAINTENANCE INVESTIGATION FOUND A CHAFED HYDRAULIC LINE AT THE NR 1 SYS PRESSURE MANIFOLD. THE LINE CHAFED UNDER AN ADEL CLAMP. IT APPEARS THAT THE RUBBER OF THE CLAMP CHAFED THROUGH THUS CAUSING METAL TO METAL CHAFING BETWEEN THE LINE AND THE CLAMP WHICH CAUSED THE LEAK. HYDRAULIC LINE, PN 601R75286-3, AIPC 29-11-00, FIG 15-35 AND CLAMP, PN M85052-2-6, AIPC 29-11-00, FIG 15-380.