As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT NR 0693 - EWR - THE 'A' SYSTEM HYDRAULIC QUANTITY DROPPED TO ZERO AFTER TAKEOFF FROM EWR. FUEL WAS DUMPED AND THE AIRCRAFT WAS RETURNED TO EWR WHERE IT LANDED WITHOUT INCIDENT. MAINTENANCE FOUND THE NR 1 ENGINE DRIVEN HYDRAULIC PUMP LEAKING. THE NR 1 HYDRAULIC PUMP WAS REMOVED AND REPLACED. LEAK AND OPERATIONAL CHECKS WERE GOOD. (W)