fatigue-critical modified structure

EASA defines “fatigue-critical modified structure” in one regulation. The wording below is reproduced verbatim from the EASA Easy Access Rules, with a link to the paragraph it comes from.

“fatigue-critical modified structure” (FCMS) means any fatigue critical structure of an aeroplane introduced or affected by a change to its type design and that is not already listed as part of the fatigue-critical baseline structure;

Article 2 · Additional Airworthiness Specifications · Regulation (EU) 2015/640 · Easy Access Rules, 20 Mar 2026 revision · Read Article 2

Defined in the same article

airworthiness limitation section
baseline structure
corrosion prevention and control programme
damage tolerance evaluation
damage tolerance inspection
fatigue-critical baseline structure
fatigue-critical structure
large aeroplane

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