Identification and Classification of Modes of Failure in Aeronautical Equipment

This paper discusses four different kinds of "failure mode" identifications. These are: By symptom, by primary failed part, by failure mechanism, and by "failure mechanism and its cause." Two years of experience with a failure mode analysis system have led to the classification of approximately 10,000 malfunctions. About 6000 of these were analyzed in sufficient detail to establish at least the identity of the primary failed piece part. About 1500 different modes of failure were thus identified. Another 1000 modes of failure by symptom were also identified. Corrective actions were expedited when the nature of part failure was identified. Identified modes of failure also form a basis for Design Review Checklists for application to future designs.