Reliability and Service Life Concepts for Sonar Transducer Applications

摘要

In recent years, the Navy has begun to include reliability requirements in procurement specifications for wet-end sonar hardware. For the most part the requested reliability evaluations have focused on exponential modeling and the use of handbook methods originally developed primarily for electronics systems. In this report, we examine the relevance of this and other approaches. Reliability concepts are reviewed without restricting their scope to the description of a single class of operating behavior. The discussion begins with the indoctrination of the mathematical functions most commonly used in reliability descriptions. Modeling of the constant, increasing, and decreasing hazard rate situations is discussed. Reliability and service-life concepts are compared and contrasted from the prediction viewpoint. The task of demonstrating reliability in as-built equipment is also dealt with. The report calls attention to some of the special problems such as limited production and long intended life associated with evaluating sonar equipment reliability. It concludes with several recommendations directed toward the systematic improvement of sonar hardware. (Author)