Meshesha, Million (PhD)Gudeta, Haileleoul (PhD)Abebe, Meskerem2020-06-122023-11-182020-06-122023-11-182009-10http://etd.aau.edu.et/handle/12345678/21549Fault isolation and diagnosis is one of the key aircraft maintenance activities performed in Ethiopian Airlines. The main features of fault diagnosis in aircraft maintenance involve multidisciplinary knowledge in aircraft functional systems and the indefinite relationship between .symptom and source or failure. In order 10 facilitate these activities the experience and knowledge of aircraft technicians plays a significant role in quickly solving aircraft system failures without delaying flight schedules. However the airline is losing significant amount of skilled and experienced technicians whose contribution to the fault diagnosis was invaluable. A knowledge based system is developed to .facilitate the fault isolation technique., in aircrafi maintenance using the experience and knowledge of skilled technicians along with the relevant mail1lenance documents and maintenance records. The domain knowledge modeling is performed using decision trees in such a way that a rule based inference can be implemented for knowledge representation. The prototype developed employs the utilization of,/ac(s and come up with conclusions based on the backward chaining inference. The rules in (he knowledge base are constructed Form analyzing the records of the aircraft maintenance resume book along with (he available maintenance documel1ls. A prolog programming language is used to demonstrate the prototype and (he result of the study has revealed that there is an accuracy of 86%. Adopting the knowledge based system is supposed to retain the aircraft maintenance knowledge and makes the airline stronger by itself rather than depending fully on human experts. The knowledge based .system needs further works in updating its knowledge base when new facts are introduced besides of creating generalized pattern for identifying system faults.enInformation ScienceThesis