SAE Aerospace Information Report AIR1871 provides valuable insight into lessons learned in the development, implementation, and operation of various health monitoring systems for propulsion engines and drive train systems. This document provides an overview of the lessons learned for ground-based systems, oil debris monitoring systems, lubrication systems, and Health and Usage Monitoring Systems (HUMS) for military and commercial programs. For each case study, this document presents a brief technical description, the design requirements, accomplishments, lessons learned, and future recommendations.The lessons learned presented in this document represent a fragment of the knowledge gained through experience when developing and implementing a propulsion health management system. Previous versions of this document contain additional lessons learned during the 1980's and 1990's that may be of additional value to the reader. This document will be maintained as technology progresses so that industry members may benefit from the lessons learned of others.This AIR is not intended to be used as a standard or legal document but rather provide an objective statement of the more important lessons learned during the development and operation of the health monitoring systems with widely varying operational requirements. It is through the use of ARP1587 and SP-478, an awareness of prior lessons learned and a clear definition of engine operational maintenance concepts that future health monitoring systems can be developed to meet the specific needs of the user.
