Design and Development Concepts for Very Long Range Spacecraft Command System

During the period from May of 1960 to date a series of flight command subsystems have been designed, developed, built and flown for deep space interplanetary probes.* These subsystems, each consisting of approximately three thousand parts, have achieved a measured mean time to failure in excess of fifty thousand hours. It is felt the techniques used in achieving this high level of reliability are of significance to any persons engaged in the field of Aerospace Technology.