What was found
DURING FLIGHT, LOSS OF FLUID QUANTITY WAS NOTED ON GREEN HYDRAULIC SYSTEM. ON DEPARTURE, QUANTITY WAS APPROXIMATELY 7/8 ON GAUGE. APPROX 30-35 MINUTES INTO FLIGHT, RESERVOIR LOW LEVEL LIGHT ILLUMINATED; QTY WAS IN YELLOW ARC. CONSTANT DECREASE IN QUANTITY WAS NOTED FOR THE DURATION OF THE FLIGHT. UPON LANDING, FLUID QUANTITY WAS IN YELLOW ARC; FLUID PRESSURE REMAINED IN GREEN ARC DURING ALL PHASED/NO CAUTION SIGNS OBSERVED. MANUAL GEAR EXTENSION PERFORMED OUT OF CONCERN FOR PARTIAL GEAR EXTENSION (FREE FALL). AN EMERGENCY WAS DECLARED AS A PRECAUTION. INSTALLED NEW LEFT ENGINE DRIVEN PUMP MAIN PRESSURE LINE (120-35694-025) PER EMB 120 MM 20-10-04. REPLENISHED RESERVOIR, LEAK CHECK GOOD.