Reliability Analysis of Life-Support Systems 640298
Advanced life-support systems have undergone considerable research and development during the past five years, so that today it is possible to make fairly accurate estimates of each system's weight and power penalties. For Projects Mercury, Gemini and Apollo straightforward analysis showed that expendables should be used for oxygen supply, carbon dioxide removal and waste provisions. For longer duration missions this problem of system selection will not be so easy, because simple trade-off studies will indicate that regenerative systems should impose less weight and volume penalties. To eliminate unfair bias, however tradeoff studies should compare systems that all have the same inherent reliability. Since operational reliability data is not available for any of these systems, it is necessary to utilize generic data to synthesize systems of equal inherent reliability and determine the true weight penalties for each type of system. This paper describes such a procedure and summarizes some of the generic failure-rate data available. In addition, an example is given to indicate more clearly the trade-off points for three carbon dioxide removal systems.