What was found
LGA-FLIGHT 3960 CREW REPORTED LOSS OF NR 1 HYDRAULIC FLUID IN FLIGHT. ISOLATION LIGHT ILLUMINATED. HYDRAULIC CONTENTS AT .5 QUARTS. NR 1 HYDRAULIC PUMP CAUTION LIGHT ALSO ILLUMINATED, BUT PRESSURE REMAINED NORMAL. EMERGENCY WAS DECLARED. FLIGHT LANDED WITH OUT ANY LOSS OF BRAKES NOR ANY PROBLEMS WITH LANDING GEAR. MAINTENANCE FOUND A HYDRAULIC LINE TO NR 1 INLET PRESSURE MANIFOLD SEVERED. RIGID HYDRAULIC LINE WAS REPLACED WITH A FLEXIBLE LINE IN ACCORDANCE WITH DEHAVILLAND DASH 8 MAINTENANCE MANUAL 20-50-52. HYDRAULIC SYSTEM BLED. NO LEAKS WERE NOTED, AIRCRAFT RETURNED TO SERVICE.