The Life Distribution and Reliability of a System with Spare Components

Abstract

The distribution of the operating life of a series system of like elements supplied with a set of spare components has been obtained for the situation when failed elements are in turn replaced by spares. This distribution has been evaluated for some common types of component life densities, and tables of expected total system life have been constructed. These expectations have been compared with those of systems with no spares as a measure of the efficacy of the additional spare components. The reliability of systems with spares has also been studied.