Statistical Reliability Estimation of Deep Space Satellites and Launch Vehicles: 1958–2022

Abstract

On-orbit flight data for deep space satellites and space launch vehicles (SLVs) servicing deep space missions operated between 1958 and 2022 is analyzed due to a lack of reliability research combining both satellites and SLVs for this class of mission. Satellite reliability is first estimated by the Kaplan–Meier estimator, and then parameterized through the Weibull distribution. This process is applied to the general deep space satellite data set as well as the delimitation of the data according to decade. SLV reliability is computed using standard maximum likelihood estimation and an evolving first-level Bayesian estimation scheme. Results from the satellite analysis demonstrated the differences between the parameterization methods used. The bulk satellite data set indicated that deep space satellites suffer from infant mortality, while certain subsets were found to have a primary wear-out failure mode. In general, U.S. deep space missions demonstrated the highest reliability. Deep space satellite reliability was also found to have increased as a function of time. Results from the SLV data set revealed that deep space launches are primarily performed by four main launch vehicle families. Additionally, most deep space SLV failures occurred in the space age (1959–1975), with the USA and USSR/Russia being the only two countries to experience deep space launch failures. With both deep space SLV and satellite reliability increasing over time, reliability is not expected to be a major hindrance to future deep space missions.