Article 2 Definitions

SI No. 1203/2021

For the purposes of this Regulation,

(a)  ‘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;

(b)  ‘baseline structure’  refers to the structure that is designed under the type certificate for that aeroplane model (that is, the ‘as delivered aeroplane model configuration’);

(c)  ‘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). A baseline CPCP is established by the type certificate holder, which can be adapted by operators to create a CPCP in their maintenance programme specific to their operations;

(d)  ‘damage tolerance evaluation’  (DTE) is a process that leads to a determination of maintenance actions necessary to detect or preclude fatigue cracking that could contribute to a catastrophic failure. When applied to repairs and changes, a DTE includes the evaluation of the repair or change and the fatigue critical structure affected by the repair or change;

(e)  ‘damage tolerance inspection’  (DTI) means a documented inspection requirement or other maintenance action developed by holders of a type-certificate or restricted type-certificate as a result of a damage tolerance evaluation. A DTI includes 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. DTIs may also specify maintenance actions such as replacement, repair or modification;

(f)  ‘fatigue-critical baseline structure’  (FCBS) means the baseline structure of an aeroplane that is classified by the type certificate holder as a fatigue-critical structure;

(g)  ‘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;

(h)  ‘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;

(i)  ‘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;

(j)  ‘maximum operational passenger seating configuration’  means the maximum passenger seating capacity of an individual aircraft, excluding crew seats, established for operational purposes and specified in the operations manual;

(k)  ‘large aeroplane’  means an aeroplane that has the Certification Specifications for large aeroplanes ’CS-25’  or equivalent in its certification basis;

(l)  ‘large helicopter’  means a helicopter that has the Certification Specifications for large rotorcraft ’CS-29’  or equivalent in its certification basis;

(m)  ‘low-occupancy aeroplane’  means an aeroplane that has a maximum operational passenger seating configuration of:

(1)  up to and including 19 seats, or;

(2)  up to and including one third of the maximum passenger seating capacity of the type- certified aeroplane, as indicated in the aeroplane type-certificate data sheet (TCDS), provided that both of the following conditions are met:

(a)  the total number of passenger seats approved for occupancy during taxiing, take- off or landing does not exceed 100 per deck;

(b)  the maximum operational passenger seating configuration during taxiing, take-off or landing in any individual zone between pairs of emergency exits (or any dead- end zone) does not exceed one third of the sum of the passenger seat allowances for the emergency exit pairs bounding that zone (using the passenger seat allowance for each emergency exit pairs as defined by the applicable certification basis of the aeroplane). For the purpose of determining compliance with this zonal limitation, in the case of an aeroplane that has deactivated emergency exits, it shall be assumed that all emergency exits are functional.

(n)  ‘repair evaluation guideline’  (REG) means a process established by the type certificate holder that guides operators to establish damage tolerance inspections for repairs that affect fatigue-critical structure to ensure the continued structural integrity of all relevant repairs;

(o)  ‘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.