- airworthiness limitation section
(ALS) means a section in the instructions for continued airworthiness, as required by points 21.A.61, 21.A.107 and 21.A.120A of Annex I (Part 21) to Regulation (EU) No 748/2012, that contains airworthiness limitations that set out each mandatory replacement time, inspection interval and related inspection procedure;
- baseline structure
means the structure that is designed under the type certificate or restricted type certificate for that aeroplane model (that is, the ‘as delivered aeroplane model configuration’);
- corrosion prevention and control programme
(‘CPCP’) means a document reflecting a systematic approach to prevent and to control corrosion in an aeroplane’s primary structure, consisting of basic corrosion tasks, including inspections, areas subject to those tasks, defined corrosion levels and compliance times (implementation thresholds and repeat intervals);
- damage tolerance inspection
(DTI) means a documented inspection requirement or any other maintenance action developed by holders of a type certificate, restricted type certificate, supplemental type certificate or existing major change approval as specified in Annex I (Part-26) as a result of a damage tolerance evaluation, including the areas to be inspected, the inspection method, the inspection procedures (including the sequential inspection steps and acceptance and rejection criteria), the inspection threshold and any repetitive intervals associated with those inspections and also, where appropriate, specification of maintenance actions such as replacement, repair or change;
- fatigue-critical baseline structure
(‘FCBS’) means the baseline structure of an aeroplane that is classified by the type-certificate or restricted type-certificate holder as a fatigue-critical structure;
- 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;
- fatigue-critical structure
(FCS) means a structure of an aeroplane that is susceptible to fatigue cracking that could lead to a catastrophic failure of the aeroplane.
- large aeroplane
means an aeroplane that has the Certification Specifications for Large Aeroplanes ‘CS-25’ or equivalent in its certification basis;
- large helicopter
means a helicopter that has the Certification Specifications for Large Rotorcraft ‘CS-29’ or equivalent in its certification basis;
- limit of validity
(LOV) means, in the context of the engineering data that supports the structural maintenance programme, a period of time, stated as a number of total accumulated flight cycles or flight hours or both, during which it is demonstrated that widespread fatigue damage will not occur in the aeroplane;
- low-occupancy aeroplane
means an aeroplane that has a maximum operational passenger seating configuration of:
- maximum operational passenger seating configuration
shall mean the maximum passenger seating capacity of an individual aircraft, excluding crew seats, established for operational purposes and specified in the operations manual;
- repair evaluation guideline
(‘REG’) means a process and implementation schedule for conducting surveys established by the type-certificate or restricted type-certificate holder for repairs that affect fatigue-critical structures to ensure the continued structural integrity of all relevant repairs, as specified in point 26.309 of Annex I (Part-26);
- small aeroplane
means an aeroplane that has the Certification Specifications for Normal-Category Aeroplanes ‘CS-23’ or equivalent in its certification basis;
- small category A helicopter
means a small helicopter that has all the characteristics of category A as defined in point (17) of Annex I to Regulation (EU) No 965/2012 and has in its certification basis the additional specifications set out in the Certification Specifications for Large Rotorcraft (CS-29) that are applicable by virtue of the reference in Appendix C to CS-27, or equivalent;
- small helicopter
means a helicopter that has the Certification Specifications for Small Rotorcraft ‘CS-27’ or equivalent in its certification basis;
- Substantiated sea conditions
means those sea conditions which were selected by the applicant for a type certificate or supplemental type certificate against which the resistance of the rotorcraft to capsize has been demonstrated and subsequently certified for ditching or emergency flotation provisions;
- widespread fatigue damage
(WFD) means a simultaneous presence of cracks at multiple locations in the structure of an aeroplane that are of such size and number that the structure will no longer meet the fail-safe strength or residual strength used for certification of that structure;