Abstract
This paper describes a preventive maintenance technology for Jumbo-Jet. To prevent malfunction of system, there are two methods. One is to establish adequate maintenance requirement and carry out the each task. Maintenance requirement for Jumbo-jet is based on Maintenance Steering Group (MSG) logic. MSG was established in 1968 and has reviewed and updated. The other is to monitor the condition of airplane system during daily operation. The 747-400, called Hi-Tech Junbo, has Aircraft Condition Monitoring System (ACMS) and Central Maintenance Computer System (CMC).
