Failure Modes and Effects Summary
FMESSection 06: System Safety & Functional Safety
Definition
A summary-level analysis that consolidates the results of detailed FMEAs to present the system-level effects of component failure modes. The FMES identifies the failure modes of replaceable items (typically LRUs — Line Replaceable Units) and their effects at the system and aircraft level. It provides a higher-level view than the detailed FMEA and is used as input to the SSA and to operational and maintenance documentation.
Where This Shows Up
The FMES is often the bridge between detailed component-level FMEA and the system-level safety assessment. While the FMEA may analyze every component within an LRU, the FMES summarizes the externally visible failure modes of each LRU and their system-level effects. This makes the FMES more useful for system integrators and for developing maintenance procedures.
Primary Sources
Describes the FMES as a summary-level companion to detailed FMEA.
Related Terms
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