Prediction of Reliability for Environmental Control and Life Support Systems

An increasing awareness of life-support system reliability has been noticed in the aerospace community as longterm space missions become realistic objectives. Literature review indicates a significant knowledge gap in the accurate evaluation of the reliability of environmental control and life-support systems. Quantitative determination of system reliability, however, is subject to large data requirements, often limiting their applicability. In an effort to address this issue, this paper presents an approach to reliability analysis for life-support system design. A simulation tool has been developed with the capability of representing complex dynamic systems with configurable failure rate functions for life-support hardware. This tool has been applied and compared with classical reliability prediction approaches. As a result of this work, it has been determined that typical life-support system configurations are likely to be more reliable than classical approaches might suggest. This is due to an inherent buffering capacity in lifesupport system design, which might be leveraged to improve the cost effectiveness of future life-support system design.