The C-5 Malfunction Detection Analysis and Recording (MADAR) subsystem performs these on-board functions for selected subsystems, including the TF39-GE-I engine. Studies were made by General Electric, the engine manufacturer, to define the extent of detection, analysis, and recording necessary for the TF39. These studies, together with the selected maintenance philosophy, defined a number of line replaceable units (LRU's) associated with the engine. The selected LRU's then determined the parameters to be monitored for the engines. Further studies defined the instrumentation requirements for obtaining the parameters. The computer programs for on-board fault isolation and incipient malfunction detection have been partially defined. Further analysis to establish limits and correlation procedures is to be completed.In addition, recorded information is analyzed in a central data bank (CDB) in a ground processing system (GPS), where refined prediction programs are being developed. The ground processing system, together with the MADAR system form a complete maintenance information system for the C-5.Future expansion of the MADAR/GPS concept would allow individual C-5's to be monitored instantaneously from a maintenance information central with all the advantages such a concept implies.