What was found
JFK - FLT 1077 - AFTER TAKEOFF EWR DURING CLIMB-OUT, SYSTEM 1 HYDRAULIC QTY AND PRESSURE WENT TO ZERO. ACCOMPLISHED ABNORMAL PROCEDURES AND AIRCRAFT DIVERTED TO JFK. ACCOMPLISHED ALTERNATE GEAR EXTENSION AND AIRCRAFT LANDED OVERWEIGHT WITHOUT INCIDENT. REPLACED BROKEN UNION ON NR 1 ENGINE HYDRAULIC SILENCER. SYSTEM LEAK AND GROUND CHECKED NORMAL OPERATION. ACCOMPLISHED OVERWEIGHT LANDING INSPECTION WITH NO DEFECTS FOUND. (M)