21L.A.221 Scope

Regulation (EU) 2022/1358

This Subpart establishes:

(a) the procedure for declaring the compliance of repair designs to an aircraft which was subject to a declaration made in accordance with Subpart C of this Annex;

(b) the rights and obligations of the declarant making a declaration of compliance of the change referred to in point (a);

(c) provisions regarding the standard repairs that do not require a declaration of design compliance.

GM1 21L.A.221 Scope

ED Decision 2023/013/R

Manuals and other instructions for continued airworthiness (such as the manufacturer’s structural repair manual, maintenance manuals and engine manuals provided by the declarant for a declaration of design compliance) for operators contain useful information for the development and approval of repairs.

When that data is explicitly identified as being declared applicable for use, it may be used by operators without further actions to cope with anticipated in-service problems arising from normal usage provided that it is used strictly for the purpose for which it has been developed.

Declared design data is data which is declared as being applicable for use by the declarant of a declaration of design compliance.

Approved data is data which is approved by an appropriately approved design organisation.

21L.A.222 Standard repairs

Regulation (EU) 2022/1358

(a) Standard repairs are repair designs to an aircraft which was subject to a declaration made in accordance with Subpart C of this Annex and which:

1. follow the design data included in the certification specifications issued by the Agency, containing the acceptable methods, techniques and practices for carrying out and identifying standard repairs, including the associated instructions for continued airworthiness; and

2. are not in conflict with the design data covered by the declaration of aircraft design compliance made in accordance with Subpart C of this Annex.

(b) Points 21L.A.223 to 21L.A.229 are not applicable to standard repairs.

GM1 21L.A.222 Standard repairs

ED Decision 2023/013/R

CERTIFICATION SPECIFICATIONS

CS-STAN⁹⁶https://www.easa.europa.eu/en/certification-specifications/cs-stan-stan… contains the certification specifications referred to in point 21L.A.222(a)(1). Guidance on the implementation of Standard Changes and Standard Repairs may be found in AMC M.A.801 of the
AMC to Part-M.

21L.A.223 Classification of repair designs to an aircraft for which design compliance has been declared

Regulation (EU) 2022/1358

(a) Repair designs to an aircraft which was subject to a declaration made in accordance with Subpart C of this Annex shall be classified as either a major or minor, using the criteria laid down in points (b) and (c) of 21L.A.203.

(b) The design compliance of a minor repair design shall be declared in accordance with point 21L.A.225.

(c) The design compliance of a major repair design shall be declared in accordance with point 21L.A.226.

GM1 21L.A.223(a) Classification of repairs designs to an aircraft for which design compliance has been declared

ED Decision 2023/013/R

(a) Clarification of the terms ‘Major/Minor’

In line with the definitions given in point 21L.A.203, a new repair is classified as ‘major’ if the result on the aircraft, engine or propeller design has an appreciable effect on structural performance, weight, balance, systems, operational characteristics, declared noise or emissions levels or other characteristics affecting the airworthiness or the environmental compatibility of the product or part. In particular, a repair is classified as ‘major’ if it requires extensive static, fatigue and damage tolerance strength justification and/or testing in its own right, or if it requires methods, techniques or practices that are unusual (i.e. unusual material selection, heat treatment, material processes, jigging diagrams, etc.).

Repairs that require a reassessment and re-evaluation of the original substantiation data to ensure that the aircraft continues to comply with all the relevant requirements should be considered ‘major’ repairs.

Repairs whose effects are considered minor and require minimal or no assessment of the original substantiation data to ensure that the aircraft continues to comply with all the relevant requirements should be considered ‘minor’.

It is understood that not all the substantiation data will be available to those persons/organisations classifying repairs. A qualitative judgement of the effects of the repair will, therefore, be acceptable for the initial classification. A subsequent review of the design of the repair may lead to it being reclassified, owing to early judgements being no longer valid.

(b) Airworthiness and environmental protection concerns for ‘Major/Minor’ classification

The following should be considered for the magnitude of their effect when classifying repairs. Should the effect be considered significant, then the repair should be classified as ‘major’.
The repair may be classified as ‘minor’ where the effect is known to be without appreciable consequence.

(1) Structural performance

The structural performance of the product includes static strength, fatigue, damage tolerance, flutter and stiffness characteristics. Repairs to any element of the structure should be assessed for their effect upon the structural performance.

(2) Weight and balance

The weight of the repair may have a greater effect upon smaller aircraft as opposed to larger aircraft. The effects to be considered are related to overall aircraft centre of gravity and aircraft load distribution. Control surfaces are particularly sensitive to the changes due to the effect upon the stiffness, mass distribution and surface profile which may have an effect upon flutter characteristics and controllability.

(3) Systems

Repairs to any elements of a system should be assessed for the effect intended on the operation of the complete system and for the effect on system redundancy. The consequence of a structural repair on an adjacent or remote system should also be considered as above (for example, airframe repair in the area of a static port).

(4) Operational characteristics

Changes may include:

—      stall characteristics,

—      handling,

—      performance and drag,

—      vibration.

(5) Other characteristics:

—      changes to load path and load sharing,

—      fire protection/resistance,

—      characteristics affecting the environmental compatibility of the product are characteristics affecting the compliance of the product with the applicable environmental protection requirements

Note: Considerations for classifying repairs as ‘Major/Minor’ should not be limited to those listed above.

(c) Examples of ‘major’ repairs

(1) A repair that requires a permanent additional inspection to the maintenance programme, necessary to ensure the continued airworthiness of the product. Temporary repairs for which specific inspections are required prior to installation of a permanent repair do not necessarily need to be classified as ‘major’. Also, inspections and changes to inspection frequencies not required to ensure continued airworthiness do not cause the classification of the associated repair as ‘major’.

(2) A repair to life-limited or critical parts.

(3) A repair that introduces a change to the aircraft flight manual (AFM).

21L.A.224 Eligibility

Regulation (EU) 2022/1358

(a) A declarant who made a declaration of aircraft design compliance in accordance with Subpart C of this Annex may declare compliance of a minor repair design of that aircraft under the conditions laid down in this Subpart. In addition, such a declaration of compliance may be also made, under the conditions laid down in this Subpart, by a design organisation approved in accordance with point (c)(3) of point 21.A.263 of Annex I (Part 21).

(b) Only the declarant who made a declaration of aircraft design compliance in accordance with Subpart C of this Annex may declare the compliance of a major repair design to an aircraft for which design compliance has been declared in accordance with Subpart C of this Annex, under the conditions laid down in this Subpart.

(c) By derogation from point (b), if the declarant who made a declaration of aircraft design compliance in accordance with Subpart C of this Annex is no longer active or is unresponsive to requests for repair designs, the compliance of a changed aircraft design may also be declared in accordance with Subpart C of this Annex by a design organisation approved in accordance with point (c)(2) of point 21.A.263 of Annex I (Part 21) within the scope of their terms of approval, or by any other natural or legal person who is able to undertake the obligations laid down in point 21L.A.47 with respect to that changed aircraft.

21L.A.225 Declaration of design compliance for minor repair designs

Regulation (EU) 2022/1358

(a) Prior to incorporating or embodying or agreeing with a production organisation to incorporate or embody a minor repair design to an aircraft for which design compliance has been declared in accordance with Subpart C of this Annex, the declarant or the organisation that has designed the minor repair shall declare that the minor repair design complies with the detailed technical specifications and the applicable environmental protection requirements with which compliance had been declared according to point 21L.A.43.

(b) The declaration of design compliance shall be made in a form and manner established by the Agency.

(c) The declarant or the organisation that has designed the minor change shall maintain a register of minor repair designs to aircraft for which design compliance has been declared, and make any declaration made in accordance with point (a) available to the Agency upon request.

AMC1 21L.A.225(a) Declaration of design compliance for minor repair designs

ED Decision 2023/013/R

REQUIREMENTS FOR THE DECLARATION OF A MINOR REPAIR

(a) Applicability of point 21L.A.225

Point 21L.A.225 should be complied with by declarants for the declaration of compliance of a minor repair, including design organisation approval (DOA) holders that declare compliance of minor changes under their privileges as per point (c)(3) of point 21.A.263 of Annex I (Part 21).

In accordance with point 21L.A.225(c) for declarations of compliance for minor repairs, the substantiating data and the declaration of compliance required by point 21L.A.225(a) should be produced but do not need to be submitted to EASA. They should be, however, kept on record and made available to EASA upon request during any oversight visit.

(b) The declaration process

The declaration process comprises the following steps:

(1) classification of the repair;

(2) applicable detailed technical specifications;

(3) determination of compliance;

(4) declaration of design compliance.

(c) Detailed technical specifications

The detailed technical specifications for a minor repair consist of the detailed technical specifications that were incorporated by reference in the declaration of design compliance that was submitted for the particular aircraft under Subpart C unless EASA has determined that these are no longer appropriate and the latest detailed technical specifications should be complied with or the declarant elects to comply with these detailed technical specifications.

(d) Determination of compliance required by point 21L.A.103(a)

The declarant should determine compliance with the applicable detailed technical specifications established for the minor change for all areas that are either physically changed or functionally affected by the minor change.

(1) Means of compliance: the declarant should define and record the means (calculation, test or analysis, etc.) by which compliance is determined. Appendix A to AMC1 21L.A.44(a) may be used for this purpose.

(2) Compliance documents: the compliance determination should be recorded in compliance documents. For minor changes, one comprehensive compliance document may be sufficient, provided that it contains evidence of all aspects for compliance.
AMC1 21L.A.227(b) may also be used, where applicable.

(3) Aircraft manuals: where applicable, supplements to manuals (e.g. aircraft flight manual (AFM), aircraft maintenance manual (AMM), etc.) may be issued.

See also additional guidance below in point (e) on embodiment/installation instructions.

(e) Embodiment/installation instructions

The instructions for the embodiment/installation of the repair (e.g. service bulletin, modification bulletin, production work order, etc.) should be defined. This may include the installation procedure, the required materials, etc.

AMC1 21L.A.225(b) Declaration of design compliance for minor repair designs

ED Decision 2023/013/R

FORM AND MANNER

The declarant should complete and file a declaration of compliance for the minor repair using the applicable form below (which can also be downloaded from the EASA website) for the declaration of minor changes/minor repair designs.

If there are any changes to the data (e.g. propeller or engine designation) that was provided in the EASA Part 21 Light database of declared noise levels as a result of the minor repair design, then this data should be added by the declarant.

The justification of the classification of the change should also be recorded.

EASA Form 201

Declaration of design compliance for a Minor Change / Minor Repair Design

AMC1 21L.A.225(c) Declaration of design compliance for minor repair designs

ED Decision 2023/013/R

REGISTER OF DECLARATIONS FOR MINOR REPAIRS

The register that is used by the declarant to record the declarations of design compliance for minor repairs should also comply with point 21L.A.7 and be easily accessible in case EASA requests the details of a specific minor change during oversight.

21L.A.226 Declaration of design compliance of major repair designs

Regulation (EU) 2022/1358

(a) Prior to incorporating or embodying or agreeing with a production organisation to incorporate or embody a major repair design to an aircraft for which design compliance has been declared in accordance with Subpart C of this Annex, the declarant shall declare that the design of the major repair complies with the detailed technical specifications and the applicable environmental protection requirements with which compliance had been declared according to point 21L.A.43.

(b) The declaration of design compliance shall be made in a form and manner established by the Agency.

(c) The declaration shall contain at least the following information:

1. the name of the person submitting the declaration, and their address/place of business;

2. the declaration reference number of the aircraft to which the major repair design relates;

3. a unique reference for identifying the major repair design;

4. indication of the detailed technical specifications and the applicable environmental protection requirements with which the compliance of the aircraft had been declared by the declarant according to point 21L.A.43;

5. a signed statement made under the sole responsibility of the person making the declaration that the design of the major repair is in compliance with the detailed technical specifications and the applicable environmental protection requirements referred to in point (4), according to the compliance demonstration plan referred to in point (d)(3);

6. a signed statement made under the sole responsibility of the person making the declaration that no features or characteristics have been identified by that person that may make the aircraft unsafe or environmentally incompatible for the intended use;

7. a description of the damage and the repair design identifying the configuration of the type design upon which the repair is made;

8. identification of all the areas of the type design and the approved manuals that are changed or affected by the repair design.

(d) The declarant that designs a major repair shall submit the declaration referred to in point (c) to the Agency. Together with this declaration, the declarant shall provide to the Agency:

1. a description of the major repair;

2. basic data about the major repair, including the operating characteristics, design features and any limitations;

3. a compliance demonstration plan detailing the means for compliance demonstration that was followed during the compliance demonstration;

4. recorded justifications of compliance within compliance data obtained from the compliance activities that have been conducted according to the compliance demonstration plan;

5. the means by which compliance with the detailed technical specifications and the applicable environmental protection requirements with which the declarant had declared that aircraft compliance according to point 21L.A.43 has been demonstrated;

6. where compliance is demonstrated by carrying out tests, a recorded justification of the conformity of the test articles and equipment, demonstrating:

(i) for the test specimen, that:

(A) the materials and processes adequately conformed to the specifications for the design;

(B) the constituent parts of the products adequately conformed to the drawings in the design; and

(C) the manufacturing processes, construction and assembly adequately conformed to those specified in the design;

(ii) that the test and measuring equipment used for the tests were adequate for the tests and appropriately calibrated;

7. reports, results of inspections or tests that the declarant found necessary to determine that the aircraft complies with the detailed technical specifications and the applicable environmental protection requirements.

(e) The declaration of a major repair to a declaration of design compliance shall be limited to the specific configuration(s) in the declaration of design compliance to which the change relates.

AMC1 21L.A.226(b) Declaration of design compliance of major repair designs

ED Decision 2023/013/R

FORM AND MANNER

The request for registration should be completed along with the declaration of design compliance and sent to EASA by email or regular mail following the information provided on the EASA website⁹⁷https://www.easa.europa.eu/document-library/application-forms/certifica… https://ap.easa.europa.eu (accessed: 20 October 2023)..

If the data sheet for airworthiness needs to be adapted, then an amended version should also be provided.

If there are any changes to the data that was provided in the EASA Part 21 Light database of declared noise levels as a result of the major repair, then this data should be added by the declarant as a new record within the EASA Part 21 Light database identifying that it is applicable after the major repair.

EASA Form 202

PART 1 – REQUEST FOR REGISTRATION AND DECLARATION OF DESIGN COMPLIANCE FOR A MAJOR CHANGE/ MAJOR REPAIR

GM1 21L.A.226(c) Declaration of design compliance of major repair designs

ED Decision 2023/013/R

INFORMATION TO BE PROVIDED TO EASA

The documents and information that are required to be provided to EASA in point 21L.A.226(c) may be provided to EASA by the declarant in advance of the submission of the declaration of design compliance for the ‘major’ change. This would be advantageous for the declarant to facilitate EASA’s investigations and to determine the need for the first-article inspection under point 21L.B.221(b).

AMC1 21L.A.226(e) Declaration of design compliance of major repair designs

ED Decision 2023/013/R

SPECIFIC CONFIGURATION(S)

The compliance-demonstration process always takes into account the specific configuration(s) in the declaration of design compliance to which the major repair relates. This (these) configuration(s) may be defined by product models/variants or by design changes to the declaration. The demonstration of compliance applies to this (these) applicable specific configuration(s). Consequently, the declaration of the major change excludes any other configurations, in particular those that already exist but are not considered in the compliance-demonstration process, as well as those that may be declared in the future.

21L.A.227 Compliance activities for declaring compliance of a major repair design

Regulation (EU) 2022/1358

Prior to making a declaration of compliance in accordance with point 21L.A.226, the declarant shall, for that specific design:

(a) establish a compliance demonstration plan detailing the means for compliance demonstration that shall be followed during the compliance demonstration. This document shall be updated as necessary;

(b) record the justification of compliance within compliance documents according to the compliance demonstration plan;

(c) perform testing and inspections as necessary in accordance with the compliance demonstration plan;

(d) ensure and record the conformity of the test articles and equipment and ensure that the test specimen conforms to the specifications, drawings, manufacturing processes, construction and assembly means in the design;

(e) ensure that the test and measuring equipment to be used for testing are adequate for testing and appropriately calibrated;

(f) allow the Agency to conduct or participate in any inspections or tests of aircraft in the final or suitably mature design and production configuration that are necessary to determine that the product with the repair design has no feature or characteristic that makes the aircraft unsafe or environmentally incompatible for the intended use;

(g) carry out flight testing, in accordance with the flight conditions for such flight testing specified by the Agency, as necessary in order to determine that the aircraft complies with the applicable detailed technical specifications and the applicable environmental protection requirements.

GM1 21L.A.227 Compliance activities for declaring compliance of a major repair design

ED Decision 2023/013/R

VOLUNTARY INVOLVEMENT OF EASA PRIOR TO THE SUBMISSION OF DECLARATION

The declarant may choose to involve EASA prior to submitting the declaration of design compliance for a major repair design. This would allow EASA to:

(a) check the scope of the product is still within the scope of Subpart C;

(b) provide guidance on the completeness of the compliance-demonstration plan and the selection of means of compliance;

(c) advise on the selection of the applicable detailed technical specifications and applicable noise requirements;

(d) provide guidance about noise tests (if applicable) and witness them;

(e) avoid any issues or delays during the first-article inspection (after submission of the declaration of design compliance and if considered necessary under point 21L.B.221(b)).

The initiation of the project may occur before starting the compliance activities or during those activities. The assignment of a dedicated project number would facilitate any subsequent communication with EASA. This will facilitate the provision of compliance documentation required by point 21L.A.226(d) which may be provided by the declarant to EASA at key stages in the compliance demonstration prior to the submission of the declaration of design compliance for the major repair design.

AMC1 21L.A.227(a) Compliance activities for declaring compliance of a major repair design

ED Decision 2023/013/R

COMPLIANCE-DEMONSTRATION PLAN FOR A MAJOR REPAIR

The compliance-demonstration plan for a major repair is a document that allows the declarant to manage and control the design of the major repair, as well as the process of compliance demonstration, and that enables EASA to investigate the root cause(s) in the event of a safety issue being discovered.

The description of the repair should include an explanation of the purpose of the repair, the pre-repair and post-repair configuration(s) of the aircraft, schematics/pictures, and any other detailed features and boundaries of the physical change (this may be supplemented by drawings or outlines of the design, if this helps to understand the design change), as well as the identification of the areas of the aircraft that are affected by the repair, and the identification of any changes to the approved manuals.

The items of the declaration of aircraft design compliance made in accordance with Subpart C that are affected by the repair and for which a new demonstration of compliance is necessary should be identified together with the means (e.g. calculation, test or analysis) by which it is proposed to demonstrate compliance.

The compliance demonstration should include the analysis for the classification of the change in accordance with GM1 21L.A.223.

In particular, the following information should typically be expected:

—      identification of the relevant personnel that make decisions affecting airworthiness and environmental compatibility, and that will interface with EASA during any physical inspection and assessment of the repaired aircraft if required under point 21L.B.221(b);

—      subcontracting arrangements for design, environmental compatibility and/or production (if applicable).

Point 21L.A.226(d)(1) ‘Description of the major repair’

An overview of the nature and type of repair that is required should be provided that describes the changes to the previously declared design.

Point 21L.A.226(d)(2) ‘Operating characteristics, design features and limitations’

The declarant should consider whether there are any affects to the operating characteristics and limitations as a result of the repair, including:

—      operating speed limitations;

—      service ceiling, maximum airfield elevation;

—      cabin pressure;

—      limit load factors;

—      number of passengers, minimum crew, payload, range;

—      weight and centre-of-gravity (CG) envelope and fuel loading;

—      performance;

—      environmental envelope;

—      runway surface conditions;

—      other items, if considered to be more appropriate, which address the specific aeronautical product.

The declarant should provide detailed information about the means of compliance with the applicable requirements identified under point 21L.A.226(a). This should include the following:

—      a compliance checklist addressing each requirement, the proposed means of compliance (see Appendix A to AMC1 21L.A.227(a) below for the relevant codes), and the related compliance document(s);

—      identification of industry standards, methodology documents, handbooks and any other acceptable means of compliance, specified in the airworthiness or noise data sheet, which have been followed in the demonstration of compliance;

—      when the compliance demonstration involves testing, a description of the ground- and flight-test article(s), test method(s), test location(s), test schedule, test house(s), test conditions (e.g. limit load, ultimate load), as well as of the intent/objective(s) of the testing; and

—      when the compliance demonstration involves analyses/calculations, a description/ identification of the tools (e.g. name and version/release of the software programs) and methods used, the associated assumptions, limitations and/or conditions, as well as of the intended use and purpose.

For every aspect mentioned above, the declarant should clearly identify whether the demonstration of compliance involves different means than those contained in the published AMC to the relevant CSs and any method (analysis or test) which is novel or unusual for the declarant.

For every aspect related to compliance with the applicable environmental protection requirements mentioned above, the declarant should clearly identify whether the demonstration of compliance involves means that are described in ICAO Doc 9501 ‘Environmental Technical Manual’.

Appendix A to AMC1 21L.A.227(a) Compliance activities for declaring compliance of a major repair design

ED Decision 2023/013/R

MEANS-OF-COMPLIANCE CODES

AMC1 21L.A.227(b) Compliance activities for declaring compliance of a major repair design

ED Decision 2023/013/R

COMPLIANCE DOCUMENTATION

(a) Compliance documentation comprises one or more test or inspection programmes/plans, reports, drawings, design data, specifications, calculations, analyses, etc., and provides a record of the means by which compliance with the applicable detailed technical specifications and environmental protection requirements has been demonstrated.

(b) Each compliance document should typically contain:

—       the reference of the detailed technical specifications or environmental protection requirements addressed by the document;

—       substantiation data demonstrating compliance (except test or inspection programmes/plans);

—       a statement by the declarant declaring that the document provides the proof of compliance for which it has been created; and

—       the declarant’s signature.

(c) Each compliance document should be unequivocally identified by its reference and issue date. The various issues of a document should be controlled and comply with point 21L.A.7.

AMC1 21L.A.227(c);(d);(e) Compliance activities for declaring compliance of a major repair design

ED Decision 2023/013/R

INSPECTIONS AND TESTS

In accordance with point 21L.A.227(d), the declarant must address the conformity of the test specimen, as well as of the test and measuring equipment.

Conformity of the test specimen

The recorded justification of the conformity of the test articles is intended to ensure that the manufactured test specimen adequately represents the declared applicable design data. Possible types of non-conformity may be the following:

—      Non-conformity between the design of the test specimen and the originally intended design data at the time of the test. These are typically identified in the early stage of the test planning, and should be addressed as early as possible (e.g. in the test plan). There may be several reasons for such a non-conformity: to account for interfaces with the test equipment, to conservatively cover several or future design configurations, etc.

—      Non-conformity between the manufactured test specimen and the design of the test specimen. Such a non-conformity may be the result of the manufacturing of the test specimen.

While it is convenient to define any possible non-conformity as early as possible, the declarant does not need to make the distinction between the two types of non-conformity above as long as they are explicitly addressed and justified by cross reference to the test plan or other documents. However, testing for the demonstration compliance with the applicable environmental protection requirements may be conducted in the final design of the product having incorporated the repair design.

Compliance demonstration is typically an iterative process in which the design is under continuous evolution. If the aircraft design evolves after the time of the inspection or test, then the final major change design should be checked against the originally intended design (as it was at the time of the inspection or test), and the differences (if any) should be analysed to ensure that the inspection or test results are representative of the final configuration. However, such changes made to the design may lead to the invalidation of the inspection or test results and the need to repeat the inspection or test. It is recommended that the declarant should have a thorough configuration management process to track the evolving design of the major repair.

Conformity of the test and measuring equipment: the configuration of the test and measuring equipment should be defined in the test plan and include the following:

—      definition/design of the test equipment (relevant tools, mechanical parts, electronic components used to execute the test); and

—      definition of the measuring equipment:

—      type/model of sensors, together with their technical characteristics;

—      position and orientation of exciters and sensors; and

—      electronic measuring equipment (in some cases, this may also include the acquisition and post-processing of data).

The configuration of the test and measuring equipment should be defined and controlled through test plans and supporting documentation. The test plan should also include the following elements:

—      the test cases, methods, and procedures for test execution;

—      the pass–fail criteria; and

—      pre-, during- and post-test inspections.

The declarant should confirm that the test and measuring equipment conform to its definition in the test plan, and that the sensors and measuring system are appropriately calibrated. Any non-conformity should be assessed, and it should be justified that it will not compromise the test purpose and results. This may be done either in the recorded justification of the conformity of the test articles and equipment or by cross reference to other documents (test minutes of meetings, test notes, etc.).

Use of the term ‘adequate’: the test and measuring equipment is considered ‘adequate’ as long as the test execution on the manufactured test specimen (including any non-conformity) and the use of the installed test set-up do not compromise the test purpose and results (for example, by providing better performance than the proposed type design, or by masking any potential failure mode or behaviour).

Changes that affect the validity of the recorded justification of the conformity of the test articles and equipment: if changes need to be introduced to the test specimen or to the test and measurement equipment after the justification has been recorded (and before the test is undertaken), then it must be updated.

Development versus compliance demonstration tests: sometimes, tests of specimens that conform to a preliminary design, but are not intended for demonstration of compliance (known as development tests), are performed as part of a risk control strategy and to develop knowledge of a subject. Problems and failures found during development are part of the process of increasing the understanding of the design, including its failure modes and the potential for optimisation. Such development tests do not need to meet the requirements of point 21L.A.227(d) and (e).

Any planned test event should be classified in advance as either a development test or a compliance demonstration test.

It is acceptable for a development test to finally form part of the compliance demonstration, and it may be declared afterwards to be a compliance demonstration test as long as it meets the requirements of point 21L.A.227(d) and (e). For this reason, it is important to keep the configuration of such tests under control.

If the test specimen used for a compliance-demonstration test has already undergone a series of previous tests that may affect or ultimately invalidate its validity due to potential non-conformity to point 21L.A.227(d) as required by point 21L.A.226(d)(6), this aspect should be considered when justifying the conformity, and specific analyses or inspections may be required to support such a statement.

Because of the above aspects, declarants may wish to inform EASA if they intend to conduct a campaign of development tests that may eventually be used as demonstration-of-compliance tests to establish whether EASA would wish to witness the tests.

AMC1 21L.A.227(f) Compliance activities for declaring compliance of a major repair design

ED Decision 2023/013/R

PHYSICAL INSPECTION OF THE FIRST ARTICLE

The declarant should be prepared for any additional investigations as notified by EASA according to point 21L.B.222(b).

Refer to AMC 21L.A.47(a) for an explanation of the activities performed under the first-article inspection.

GM1 21L.A.227(f) Compliance activities for declaring compliance of a major repair design

ED Decision 2023/013/R

TESTS AND INSPECTIONS PERFORMED BY THE AGENCY

The declarant should inform EASA sufficiently in advance about the execution of significant inspections and tests that are used for compliance-demonstration purposes in order to permit EASA the opportunity to perform or witness these inspections or tests in advance of any physical inspection and assessment of the repaired aircraft if required by point 21L.B.221(b).

This would be advantageous for the declarant to avoid any issues or delays if a physical inspection and assessment of the repaired product is required.

Additionally, the declarant may propose to EASA to perform or witness flight or other tests of particular aspects of the product during its development and before the design of the major repair is fully defined. However, before EASA performs or witnesses any flight test, the declarant should perform these tests and should ensure that no features of the product preclude the safe conduct of the evaluation requested.

A recorded justification of the conformity of the test articles and equipment as per point 21L.A.226(d)(6) is required for the above tests.

21L.A.228 Obligations of the declarant of a declaration of design compliance of a repair design

Regulation (EU) 2022/1358

The declarant of a declaration of design compliance shall:

(a) for minor repair designs maintain a register of those declarations and shall make those declarations available to the Agency upon request;

(b) provide to the organisation performing the repair all the necessary instructions to install or embody the repair design;

(c) support any production organisation producing parts for the repair design, and ensure that those parts are produced using production data that is based upon the design data that is provided by the declarant;

(d) if a repair design is declared subject to limitations, transmit these limitations to the operator using a documented procedure that is made available to the Agency upon request;

(e) undertake the obligations of a declarant of design compliance of a repair design of Subpart A of this Annex.

21L.A.229 Unrepaired damage

Regulation (EU) 2022/1358

The declarant of design compliance of an aircraft in accordance with Subpart C of this Annex or an approved design organisation with privileges provided in accordance with point (c)(3) of point 21.A.263 of Annex I (Part 21) and with the appropriate scope of approval shall conduct an evaluation of the airworthiness and environmental compatibility consequences of any damage to such aircraft that is left unrepaired and that is not covered by previously declared data. Any necessary limitations shall be processed in accordance with point (d) of point 21L.A.228.

GM1 21L.A.229 Unrepaired damage

ED Decision 2023/013/R

This process is not intended to supersede the normal maintenance practices defined by the declarant (e.g. blending out corrosion and re-protection, stop drilling cracks, etc.), but addresses specific cases not covered in the manufacturer’s documentation.