An AID to preliminary design of missile prelaunch checkout equipment

The purpose of a missile prelaunch confidence checkout is to assure the commander that the weapon contains no undetected mission‐failure‐causing defects and, indeed, is ready to perform its assigned mission. If all the prelaunch tests that would be desirable cannot be scheduled because of the operational necessity to launch within a limited amount of time, then engineering and operational evaluations must be employed to determine the theoretically optimum content of the limited checkout and also the required capability of the checkout equipment. As an aid in preliminary design, perhaps as an objective point of departure for design compromises, this paper addresses the problem of making these design decisions from an operational viewpoint and, by use of reliability estimates as the basis for the analysis, develops (1) quantitative criteria for the value of inclusion of individual checks in the checkout, (2) an expression for the required efficiency of the checkout equipment, and (3) a mathematical method for determining the content of a theoretically optimum checkout. The latter result is for the case exemplified by ballistic missiles where, in general, all missile functions are energized prior to launch and where one operational constraint is dominant, namely, time allowed for checkout. The determination of the optimum checkout content can be done graphically, and the method developed can also be used to ascertain the launch confidence achieved by the checkout equipment of present missile systems.