Digital Command - A Network for Manned Spaceflight

Error-free radio command control of manned and unmanned spacecraft used in the manned spacecraft program is mandatory for mission success. This paper outlines the history, philosophies, and methods used in the development of the Digital Command Network implemented for this purpose. This network is designed to the concepts of error detection, versatility, and reliability. This paper will explain the basic concepts of design, the configuration of ground command sites involved, and the overall network which evolved to satisfy the command requirements of manned spaceflight control.