Final reliability-growth results for EMATT, a 1-shot device

A redesign effort has been carried out for the Expendable Mobile ASW (antisubmarine warfare) Training Target (EMATT), an open ocean 1-shot expendable target employed in simulated combat missions. The redesign was followed by a reliability growth, viz. a test, analyze, and fix (TAAF) program consisting of rigorous in-water testing aimed at validating redesign, verifying design margin, and continuously improving reliability. The testing was conducted in three intervals. Interval 1 consisted of in-water/laboratory runs at the manufacturer´s facility. Interval 2 consisted of simulated in-water tests and both air and surface launches. Interval 3 consisted of air and surface launches. Many important design and procedural problems were identified and corrected during, and at the conclusion of, each test phase. The Army Systems Analysis Activity (AMSAA) reliability growth model shows reliability growth from an initial 0.4 to 0.8. The reliability objective for EMATT is 0.8