Diagnostic Needs of the Space Shuttle Main Engine

A study is being conducted for NASA on potential diagnostic system improvements to the Space Shuttle Main Engine (SSME). This paper reports midterm progress including: (1) the results of a failure mode review identifying key diagnostic needs; (2) the results of a survey of diagnostic techniques that might be applied to the SSME; and (3) application to the SSME of a Battelle developed tool (the Failure Information Propagation Model, or FIPM) for analysis of diagnostic needs. It is concluded that opportunities for significantly improved diagnostics exist in a number of areas. Future plans are described that are directed toward development of a diagnostics strategy and design recommendations for an improved diagnostic system for the SSME.