scope:

Purpose - The purpose of this handbook is to establish and maintain consistent and uniform methods for estimating the inherent reliability (i.e., the reliability of a mature design) of military electronic equipment and systems. It provides a common basis for reliability predictions during acquisition programs for military electronic systems and equipment. It also establishes a common basis for comparing and evaluating reliability predictions of related or competitive designs. The handbook is intended to be used as a tool to increase the reliability of the equipment being designed.

Application - This handbook contains two methods of reliability prediction - "Part Stress Analysis" in Sections 5 through 23 and "Parts Count" in Appendix A. These methods vary in degree of information needed to apply them. The Part Stress Analysis Method require as greater amount of detailed information and is applicable during the later design phase when actual hardware and circuits are being designed. The Parts Count Method requires less information, generally part quantities, quality level, and the application environment. This method is applicable during the early design phase and during proposal formulation. In general, the Parts Count Method will usually result in a more-conservative estimate (i.e., higher failure rate) of system reliability than the Parts Stress Method.

Computerized Reliability Prediction - Rome Laboratory - ORACLE is a computer program developed to aid in applying the part stress analysis procedure of MIL-HDBK-217. Based on environmental use characteristics, piece part count, thermal and electrical stresses, subsystem repair rates and system configuration, the program calculates piece part, assembly and subassembly failure rates. It also flags overstressed parts, allows the user to perform tradeoff analyses and provides system meantime-to-failure and availability. The ORACLE computer program software (availability both VAX and IBM compatible PC versions) is available at replacement tape/disc cost to all DoD organizations, and to contractors for application on specific DoD contracts as government furnished property (GFP). A statement of terms and conditions may be obtained upon written request to: Rome Laboratory/ERSR, Griffiss AFB, NY 13441-5700.