Operations and Functions of the Apollo Guidance Computer During Rendezvous

Abstract

The Lunar Orbit Rendezvous concept of two manned spacecraft is a critical activity in the success of a lunar-landing mission. In present and future Apollo flights the command module and the lunar module are both equipped with an on-board capability to enable the crew to effect and complete a rendezvous. This on-board capability is centered around the Apollo Guidance Computer which receives inputs from the crew, as well as information from other on-board subsystems, to perform the guidance and navigation computations necessary to control the intercept.The purpose of this paper is to describe the operational functions performed by both spacecraft computers, their design, program organization, control options, displays, inputs, and crew interfaces. A time history of the operations and procedures used by the crew, and the computer's role, in each vehicle during rendezvous is discussed, as well as presentation of the results obtained by the on-board system for actual flights.