Abstract. The article provides an overview of the analysis of early spacecraft. The results of reliability studies are considered and the causes of failures are identified. As a result, some studies examined cause-and-effect hypotheses for reducing the failure rate of spacecraft, and some considered design or implementation deficiencies. Failure classes are listed in order of increasing severity of failures and they are in turn divided into categories. The article concludes with a division of failures into hazard categories, shown in a tabular form, and summary data are presented.

Keywords: spacecraft, reliability, infant mortality, systematic malfunctions, launch vehicle, software.