What was found
THE AIRCRAFT LANDED AT NRT WITH THE RT MLG NR 4 WHEEL/TIRE ASSEMBLY MISSING. THE AIRCRAFT LANDED SAFELY. THE RT MLG TRUCK ASSEMBLY WAS REPLACED DUE TO NR 4 AXLE DAMAGE. THE NR 4 BRAKE ASSEMBLY WAS REPLACED DUE TO DAMAGE CAUSED BY DEPARTURE OF NR 4 WHEEL ASSEMBLY. A TIRE AND WHEEL ASSEMBLY WAS INSTALLED IN THE NR 4 POSITION. IN ADDITION, THE NR 3, 7 AND 8 WHEEL ASSEMBLIES WERE REPLACED DUE TO OVERLOAD. *S/D* ENGINEERING CONCLUDED THAT THE LOSS OF THE RT MLG NR 4 WHEEL/TIRE ASSEMBLY WAS DUE TO BEARING FAILURE.