The Canadian Department of National Defence has identified a need for improved Engine Health Monitoring procedures for the new Canadian Patrol Frigate (CPF). The CPF propulsion system includes two General Electric LM2500 gas turbines, a high-pressure-ratio engine with multiple stages of compressor variable geometry. A general method for predicting the thermodynamic performance of variable geometry axial compressors has been developed. The new modeling technique is based on a meanline stage-stacking analysis and relies only on the limited performance data typically made available by engine manufacturers. The method has been applied to the LM2500-30 marine gas turbine and the variations in engine performance that can result from a malfunction of the variable geometry system in service have been estimated.

The F404-GE-400 engines of the CF-18 aircraft are the first engines of the Canadian Forces to be maintained under a formal on-condition maintenance program. In support of this program, the Canadian Forces are developing advanced troubleshooting and performance monitoring procedures based on information recorded by the aircraft In-flight Engine Condition Monitoring System (IECMS). A suite of computer programs has been developed that enables maintenance personnel to access, display, and analyze in-flight event data recorded by the IECMS and to track the performance of individual engines based on “health indices” derived from the IECMS take-off ground roll recordings. The new techniques have been under evaluation at each of the CF-18 main operating bases for a period of approximately 14 months. Results to date indicate that the IECMS recordings provide a considerable amount of information of benefit to engine technicians and maintenance planners.

The F404-GE-400 engines of the CF-18 aircraft are the first engines of the Canadian Forces to be maintained under a formal on-condition maintenance program. In support of this program, the Canadian Forces are developing advanced troubleshooting and performance monitoring procedures based on information recorded by the aircraft In-flight Engine Condition Monitoring System (IECMS). A suite of computer programs has been developed which enables maintenance personnel to access, display and analyze in-flight event data recorded by the IECMS and to track the performance of individual engines based on “health indices” derived from the IECMS takeoff ground roll recordings. The new techniques have been under evaluation at each of the CF-18 main operating bases for a period of approximately 14 months. Results to-date indicate that the IECMS recordings provide a considerable amount of information of benefit to engine technicians and maintenance planners.