What was found
FLT 6473 - JFK-IAD - DURING DESCENT, AIRCRAFT MADE AN SCHEDULED LANDING WITH ONE DISCREPANCY WHICH WAS LOST ALL HYDRAULIC PRESSURE AND CREW HAD TO PUMP GEAR DOWN. AIRCRAFT LANDED AND WENT TO GATE WITH NO FURTHER PROBLEMS. MAINTENANCE INSPECTED AND REMOVED AND REPLACED TWO HYDRAULIC LINES THAT WERE CHAFED. OPS CHECK OK. AIRCRAFT WAS RELEASED AND APPROVED FOR RETURN TO SERVICE. (M)