What was found
AIRCRAFT WAS GROUNDED: DURING TAKEOFF AND LANDING MID FREQUENCY VIBRATION FELT THROUGHOUT THE CABIN. OCCURRED WITH MAIN TIRES ON THE GROUND AND VIBRATION FREQUENCY CORRESPONDED TO AIRCRAFT GROUND SPEED. DURING DISCUSION WITH TOWER AARF WAS DISPATCHED AIRCRAFT LANDED WITHOUT INCIDENT. INSPECTED MLG WHEELS IAW FIM 32-11-00-810-802, FOUND NR 1 & 4 TIRES FLAT SPOTTED AND WORN. MAINTENANCE REPLACED NR 1 MAIN WHEEL ASSY'S IAW AMM 32-45-11.