JETA: A knowledge-based approach to aircraft gas turbine engine maintenance

Abstract

Aircraft gas turbine engine maintenance is a complex task requiring not only specialized technical skill but effective integration of many sources of information. Traditionally, military maintenance technicians make extensive use of common sense knowledge, equipment manuals, pilot reports, instrument readings, engine settings and physical observations. Reasoning based upon patterns in sensor data, case histories and past maintenance is infrequently carried out. Difficulties in maintenance arise from the need to quickly restore the engines to an operational state, the frequent reassignment of technicians and the awkward access to, and interpretation of, data. There is a need to overcome these factors. This paper describes a knowledge-based diagnostic system for military gas turbine aero-engines. The objectives were to develop a system which encodes the heuristics of technicians and to provide an expandable framework for automating the technical manuals and incorporating explanations, data interpretation, as well as case history and model-based reasoning. The eventual goal is to apply the system to the maintenance of complex mechanical equipment and have it reason, in an on-line mode, with data obtained from a data acquisition system. A description of the application area and the features of the system, in its current stage of development, are discussed. This paper will be of practical benefit to those developing knowledge-based maintenance systems for complex mechanical equipment.