Abstract:Uncertainty analysis of system reliability estimate is presented to optimize system reliability estimate.All minimal cut sets were obtained through fault tree qualitative analysis.The fault tree was converted to series parallel system based on minimal cut sets,and the system reliability estimate variance could be approximately represented as a linear combination of the variance estimates of the individual components.Then,some components which have a great effect on the variance associated with the system reliability estimate are discriminated. Finally,efficiency and accuracy of the method was demonstrated through uncertainty analysis of an torpedo system reliability estimate.