What was found
ON TAKEOFF WHEN LANDING GEAR WAS CALLED UP HYDRAULIC "A" SYSTEM QUANTITY WENT TO ZERO, HYDRAULIC "A" SYSTEM LOSS COMPLETED APPROPRIATE ABNORMAL CHECK LIST. NORMAL LANDING, HYDRAULIC "A" SYSTEM PUMP SWITCHES AND FLUID SHUTOFF WERE TURNED OFF FOR 27 MINUTES. CORRECTIVE ACTION: REPLACED TWO FLEXIBLE HOSES AT NOSE LANDING GEAR ACTUATOR UP LINE LOCATED 5 FEET AFT THE FORWARD PIT FORWARD BULKHEAD PER GMM6.3.23-1, REPLACED NR 1 ENGINE HYDRAULIC PUMP AND CASE DRAIN FILTER, IAW 29-11-32 AND M/M29-11-41. CHECK NORMAL.