Abstract :
The concepts of operational capability and life-cycle cost are used to develop a managerial decision model for establishing design goals for system reliability and maintainability (R&M), and the apportionment of these goals to subsystem design levels, during the conceptual phase of system development. The model uses experience, engineering judgment, etc. to provide input data on attainable R&M levels and the programs required for achieving them. Solving the model allocates effort where the results are best according to a life-cycle cost objective function which reflects managerial aversion to cost and risk. Specifically, the model (with the solution technique) provides program managers a systematic approach for establishing R&M design goals when: 1) attainable R&M levels are not known with certainty; 2) costs are not known with certainty; 3) limited funds are available for system development; 4) constraints exist on at least some of the following factors: system availability, weight, and R&M; 5) some R&M alternatives are interdependent; and 6) the suitability of establishing R&M design goals depends on both cost and risk considerations. Utility of the model for R&M program decision making is demonstrated by applying it to the analysis of a system with 20 subsystems, each of which has a maximum of 9 possible R&M combinations.
