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Reliability Model and Data Acquisition for Solid Propellant Missiles


OBJECTIVE: Develop an innovative high-fidelity, comprehensive framework that estimates reliability and aids in reliability growth for missile systems employing solid propellant motors. DESCRIPTION: The Targets and Countermeasures Directorate of the Missile Defense Agency (MDA) employs refurbished target systems to simulate current threats with improved reliability. Innovative techniques to enhance confidence levels in high reliability target systems are solicited. Reliability is generally defined as the probability that a given item will perform its intended function for a given time period under a given set of conditions. For a missile system this translates into the probability of a payload being delivered to a point-in-space to within a spatial and temporal accuracy requirement. The time period is the time of missile flight and the conditions are the flight environments. Reliability growth is the positive improvement in the reliability parameter of a system over a period of time due to implementation of corrective actions to system design, operation, or maintenance procedures, or the associated manufacturing processes (Reference 1). Reliability parameters are determined for the overall system reliability probability with confidence limit(s), as well as for critical components (e.g. solid rocket motors) reliability. The reliability framework involves both processes in the course of missile system development and an analytical model to track reliability estimates over the developmental and operational time. This framework will be used by independent government assessments. Thus, proposers must address at a minimum (1) methods to identifying the most probable failure points, (2) handling of both single-point-of-failure components as well as components with backup redundancies, (3) the acquisition of component reliability data, (4) assessment of quality/reliability in manufacturing processes as evidenced by acceptance testing results, (5) subsystem qualification test results, (6) system integration testing, and (7) any redesign and retesting that results. A portion of the Phase II activity will apply the framework to a generic MDA/TC target system. Since MDA flight tests are expensive, high reliabilities (>90%) with high confidence are required. PHASE I: Phase I of this effort should concentrate on the overall framework of a general purpose reliability growth process and the reliability estimation tracking applicable to any missile system employing solid propellants (e.g. tactical missiles, cruise missiles, space launch missiles, offensive ballistic missiles, test missiles, and/or interceptors). The emphasis should also be on the management approach to reliability growth during the design/testing phases and paths to obtain fundamental component reliability data. The bidder can assume that model inputs for the eventual user will include such traditional data as (1) Electrical, Mechanical, and Thermal Stress Analyses, (2) Failure Modes, Effects, and Criticality Analysis (FMECA) efforts, (3) dormant storage time/conditions, and (4) results of acceptance, qualification and integration testing. The bidder shall show how component level reliability data can be obtained (including mechanical, electrical, and software/firmware components), and how through qualification and integration testing the reliability estimate can be verified and further refined. All elements of the final analytical model are not expected at the completion of Phase I; but the structure and the requirements for the analytical model and the management approach to reliability growth are expected. PHASE II: Phase II shall (1) complete the analytical model, (2) expand the management approach to reliability growth to include the operational phase of the missile systems, and (3) apply the comprehensive framework to a specific government furnished target system. The analytical model shall be capable of predicting total missile system reliability. All required inputs shall be defined, all algorithms encoded, and all outputs designed and formatted. A User"s Manual shall be written. Another major output of Phase II shall be a description of the recommended reliability growth processes in a form suitable for target acquisition request for proposals (RFPs). During Phase II a tailoring of the framework (both processes and analytical model) specifically for MDA Targets is expected. A generic targets parts list will be provided at the onset of Phase II. Special attention shall be paid to legacy solid rocket motors and their testing prior to use. PHASE III: The contractor will work with existing target contractors to implement the reliability processes that have been approved by MDA to the degree acceptable to the target prime contractor. DUAL USE/COMMERCIALIZATION POTENTIAL: Much of the statistical modeling and process of reliability growth with test is applicable to many complex systems employing mechanical, electrical and software components. This could include aircraft, unmanned aerial vehicles, manufacturing apparatus, ground transportation systems, and home or office appliances.
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