Unreliability of a complex system with parallel redundancy and repair

Abstract An analytical method has been developed for evaluating the unreliability of complex systems with repair when redundancy is active. Failures of components are assumed to follow the Poisson process and to be independent of each other. The calculation algorithms of the method can be used in practice for approximations of fault tree. A numerical comparison of the method with the Markov process and a complete example of a fault tree evaluation are presented.