What was found
EWR - FLT 668 - THE ACFT HAD A HISTORY OF THE FLAPS NOT EXTENDING FOR LANDING. THE 'ABNORMAL' PROCEDURES WERE COMPLIED WITH AND THE ACFT LANDED WITHOUT INCIDENT. MAINTENANCE FOUND THE RT SIMPLEX BEVEL GEARBOX IN THE NR 6 POSITION BINDING. THE NR 6 RT SIMPLEX BEVEL GEARBOX WAS REMOVED AND REPLACED. IN ADDITION, THE NR 1 AND NR 2 RT FLAP TRANSMISSIONS WERE REMOVED AND REPLACED AS A PRECAUTIONARY MEASURE DUE TO THE HISTORY OF FLAPS LOCKING OUT. A FUNCTIONAL RIG CHECK OF THE RT FLAP SYSTEM WAS PERFORMED PER MM 27-51-00 AND ALL OPERATION CHECKED GOOD. (W)