Failure Analysis Through Autopsy of Undersea Acoustic Transducers

As part of the Sonar Transducer Reliability Improvement Program (STRIP), the Applied Physics Laboratory, the Naval Research Laboratory, and the Naval Undersea Systems Center have been studying ways to increase the reliability of undersea acoustic transducers, especially the watertight integrity of seals, cables, and connectors. The objectives are threefold: to investigate failures in operational transducers and determine their failure modes; to investigate developmental transducer systems; to determine aging rates for seals, cables, connectors, and other components that affect leak rates and thus life expectancy. To accomplish these tasks, (a) electrical tests and visual inspections are performed on transducer arrays currently in service to determine whether failures are occurring and to collect background data, and (b) autopsies are conducted on failed or failing developmental and in-service units to define failure modes and to recommend corrective action; besides physical dissection and inspection, the autopsies include mechanical, physical, chemical, electrical, acoustical, and metallurgical tests. Both the in-service inspections and the autopsies are documented on videotape.