A description of a guidance or orbital control process, particularly applicable for use with a 24-hour communications satellite. The process deals with certain of the guidance problems involved in such a satellite, namely, the determination of the differences between the actual and the desired orbit, so that the corrections may be applied to keep the satellite on station. The orbit is observed from ground stations, and the errors calculated, so that commands to apply corrective thrust can be transmitted to the vehicle. The work presented will make it possible to determine the amount of fuel needed to return the satellite to its desired orbit. 94 pp.