26.307 Damage tolerance data for existing changes to fatigue-critical structure

• Regulation (EU) 2020/1159 found in: CS-26 Additional Airworthiness Specifications for Operations (No 2015/640) Part-26 (Mar 2023)
• Regulation (EU) 2024/2954 found in: CS-26 Additional Airworthiness Specifications for Operations (Part-26) (Oct 2025)

26.307 Damage tolerance data for existing changes to fatigue-critical structure Regulation (EU) 2020/1159 (a) A holder of a type-certificate (TC) or restricted TC for a turbine-powered large aeroplane certified on or after 1 January 1958 certified to carry 30 passengers or more, or with a payload capacity of 3 402 kg (7 500 lbs) or more, for changes and fatigue-critical modified structure (FCMS) existing on 26 February 2021 shall: (i) review existing design changes (design modifications) and identify all changes that affect FCBS identified in accordance with point [26.306](#_DxCrossRefBm881534088); (ii) for each change identified in accordance with paragraph (a)(i), identify any associated fatigue-critical modified structure (FCMS); (iii) for each change identified in accordance with paragraph (a)(i), perform a damage tolerance evaluation and establish and document the associated damage tolerance inspections; (b) The holder of a type-certificate (TC) or a restricted TC shall submit the list of all fatigue-critical modified structure (FCMS) identified in accordance with paragraph (a)(ii) to the Agency before 26 February 2022, for approval. (c) The holder of a type-certificate (TC) or a restricted TC shall submit the damage tolerance data, including DTI, resulting from the evaluation performed in accordance with paragraph (a)(iii) to the Agency before 26 August 2022, for approval. (d) Upon approval by the Agency of the FCMS list submitted in accordance with paragraph (b), the holder of a type- certificate (TC) or restricted shall make that list available to operators and persons required to comply with points [26.330](#_DxCrossRefBm881534079) and [26.370](#_DxCrossRefBm881534105). #### 26.307 Damage tolerance data for existing changes to fatigue-critical structure *Regulation (EU) 2024/2954* (a) A holder of a TC or a restricted TC for a large aeroplane certified on or after 1 January 1958 and certified to carry 30 passengers or more, or with a payload capacity of 3 402 kg (7 500 lb) or more, for changes and fatigue-critical modified structures (FCMS) existing on 26 February 2021 shall: (i) review existing design changes and identify all changes that affect FCBS identified in accordance with point [26.306](#_DxCrossRefBm783605488); (ii) for each change identified in accordance with point (i), identify any associated FCMS; (iii) for each change identified in accordance with point (i), perform a damage tolerance evaluation and establish and document the associated DTIs. (b) The holder of a TC or a restricted TC shall submit the list of all FCMS identified in accordance with point (a)(ii) to the Agency before 26 February 2022, for approval. (c) The holder of a TC or a restricted TC shall submit the damage tolerance data, including DTI, resulting from the evaluation performed in accordance with point (a)(iii) to the Agency before 26 August 2022, for approval. (d) Upon approval by the Agency of the FCMS list submitted in accordance with point (b), the holder of a TC or a restricted TC shall make that list available to the holders of a STC or a major change approval that are required to comply with point [26.330](#_DxCrossRefBm783605479) and to all known operators of such aeroplanes and, on request, to organisations responsible for the management of continuing airworthiness to support the operators that are required to comply with point [26.370](#_DxCrossRefBm783605505).