What was found
THE FLIGHT RETURNED TO JFK DUE TO LOSS OF THE CENTER HYDRAULIC SYSTEM AND A FLAPPING NOISE FROM UNDER THE RIGHT WING AREA. THE FLIGHT CREW DECLARED AN EMERGENCY AND LANDED OVERWEIGHT AT 351,000 POUNDS. TOUCHDOWN WAS AT 170 KTS BUT NO DESCENT RATE WAS GIVEN. MAINTENANCE DISCOVERED A BROKEN HYDRAULIC LINE IN THE RIGHT WHEEL WELL GOING TO THE RIGHT MAIN LANDING GEAR SEQUENCE VALVE. THE LINE WAS REPLACED AND SYSTEM OPERATION WAS NORMAL THEREAFTER (2010-D0828)(DL764101853).