What was found
AIRCRAFT WAS GROUNDED. EMERGENCY DECLARED. GYE-MIA FLIGHT RETURNED TO GYE. OVERWEIGHT LANDING UNEVENTFUL. CREW REPORTED HIGH VIBRATIONS ON THE LEFT ENGINE DUE TO BIRD STRIKE. REMOVED AND REPLACED FAN BLADES 16, 17, 18, 20, 21, 22 AND BLENDED 11 FAN BLADE IAW AMM 72-31-02. OPERATIONAL CHECK GOOD.