What was found
GUM - FLT 953 - AFTER DEPARTURE AT CRUISE FLT 310, HYD SYSTEM 'A' QTY BEGAN TO DROP SLOWLY. THE QTY DROPPED STEADILY FROM 4.3 GALLONS TO 2.6 GALLONS IN APPROX 20 MINUTES. THE QTY STABILIZED AT 2.6 GALLONS. AIR RETURN TO GUAM. MAINTENANCE T/S SYSTEM FOUND RIGID LINE ON 'B' SYSTEM SUPPLY LINE CHAFING. REMOVED FAULTY LINE AND INSTALLED SERVICEABLE FLEX-LINE (HOSE) PER MM SEC 29-00. SERVICED AS REQUIRED, OPS CNA LEAK CHECKED GOOD. NEEDS TO ISSUE DIP TO REPLACE FLEX LINE WITH RIGID LINE. (M)