The Spacecraft Test and Evaluation Program

Essential to the success of any development program are: (a) sound basic design; (b) discriminate selection of materials and components; and (c) careful fabrication. The function of test evaluation, as a fourth phase in the development plan, is to determine the degree to which the three basic requirements listed have been satisfied. It might be suggested that a unique feature of the Telstar satellite program has been the joint achievement of depth and concurrency in all four development phases. Such an approach has been dictated both by program urgency and the extraordinary cost of failure in an undertaking of this nature. In the process, each phase of the spacecraft development effort has served to reinforce collaterally every other phase, to a degree not normally realized in a sequentially structured program. The spacecraft design is largely derived from existing systems of proven reliability. Maximum safety margins permitted by size and weight limitations have been utilized. Components and materials have been selected wherever possible on the basis of successful prior use in related applications. Manufacture and assembly operations have been carried out under carefully controlled conditions. The spacecraft test evaluation has served to demonstrate the effectiveness of these measures in providing a design which would survive the launch and operate satisfactorily in the orbital environment. This article will cover both general and detailed aspects of the spacecraft test evaluation, as the 1007