What was found
AIRCRAFT RETURNED OF FLIGHT, STRONG VIBRATION IN NOSE LANDING GEAR. DURING MAINTENANCE CHECK WAS DETECTED LT NOSE LANDING GEAR DOOR OPENED, DOOR AND ACTUATOR WERE CHECKED AND ACTUATOR WAS REPLACED IAW MM 32-22-01, TEST FLIGHT WAS PERFORMED AND THREE CYCLES OF LANDING GEAR WERE ACCOMPLISHED, ALL CORRECT.