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21L.A.107 Declaration of design compliance for a major change

Annex Ib · Regulation (EU) No 748/2012 · EAR revision 27 Nov 2025

IRImplementing rule

21L.A.107Declaration of design compliance for a major change

(a)Prior to installing or incorporating or agreeing with a production organisation to install or incorporate a major change to the design of an aircraft for which design compliance has been declared in accordance with Subpart C of this Annex, the organisation that has designed that major change shall declare that the design of that major change and the areas affected by that change comply with:

1.either the detailed technical specifications incorporated by reference in the declaration of design compliance of the aircraft, unless those detailed technical specifications or parts of them are no longer applicable in accordance with point 21L.B.61 because the Agency has determined that experience from other similar products in service or products that have similar design features has shown that unsafe conditions may develop and the detailed technical specifications that were referenced in the declaration of design compliance of the aircraft do not address this unsafe condition, or

2.the detailed technical specifications applicable on the date on which the declaration is made in accordance with point 21L.B.61, if chosen by the declarant; and

3.the applicable environmental protection requirements referred to in point 21L.B.61 which are applicable on the date on which the declaration is made.

(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 change relates;

3.a unique reference for identifying the major change;

4.indication of the detailed technical specifications and the applicable environmental protection requirements with which the declarant declares compliance;

5.a signed statement made under the sole responsibility of the person making the declaration that the design of the major change 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 signed commitment that the person making the declaration will undertake the obligations referred to in point 21L.A.47 in respect of the changed aircraft design;

8.the instructions for continued airworthiness;

9.the operating limitations, if changed;

10.the data sheet for airworthiness and, if applicable, the record of emissions compliance;

11.the data sheet for noise, if applicable;

12.any other conditions or limitations prescribed for the aircraft in the applicable detailed technical specifications and the applicable environmental protection requirements with which the declarant declares compliance.

(d)The declarant that designs a major change 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 change;

2.basic data about the major change, 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 the compliance data obtained from the compliance activities that have been conducted according to the compliance demonstration plan;

5.the means by which such compliance with the applicable detailed technical specifications and applicable environmental protection requirements in point 21L.B.61 has been demonstrated;

6.where compliance is demonstrated by carrying out tests, 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 test were adequate for the test and appropriately calibrated;

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

(e)The declaration of a major change 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.

IR · 21L.A.107 — Regulation (EU) No 748/2012 · Regulation (EU) 2022/1358 · Initial Airworthiness Easy Access Rules · EAR revision 27 Nov 2025

AMCAcceptable means of compliance

AMC1 21L.A.107(b)Declaration of design compliance for a major change

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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 website. 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 change, 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 change. EASA Form 202 PART 1 – REQUEST FOR REGISTRATION AND DECLARATION OF DESIGN COMPLIANCE FOR A MAJOR CHANGE/ MAJOR REPAIR

1. Identification of Activity
Major ChangeMajor Repair
2. Product Identification
2.1 ApplicabilityDeclared Type Name (this must be a unique means to identify the aircraft)
Declared Model Name(s)
Original Declarant
Registered Declaration No
2.2 Product CategorySmall Aeroplane with a MTOW of 1 200 kg or less and a max. seating configuration of 2 persons Sailplane with a MTOW of 1 200 kg or less Powered Sailplane with a MTOW of 1 200 kg or less Balloon designed for no more than 4 persons Hot Air Airship designed for no more than 4 persons
2.3 Technical SpecificationsPlease specify the applicable technical specifications, e.g. CS-23 (if these are not the original technical specifications against which compliance was originally declared in accordance with Part 21 Light Subpart C due to the reasons stated in 21L.A.107 (a)(1) or (2) then this should be indicated here).
2.4 Environmental Protection Requirements (if applicable)Please specify the environmental protection requirements with which compliance has been determined
3. Description
3.1 TitlePlease limit to 40 characters
3.2 Description
3.3 Affected Areas including manuals
3.4 Re-InvestigationsCompliance Demonstration Plan – doc. Ref.: (Please provide the reference of the Compliance Demonstration Plan required by 21L.A.107(d)(3) or 21L.A.226(d)(3), respectively) Documentation, if changed, to submit with the Declaration in accordance 21L.A.107(c): • Airworthiness Data Sheet • Aircraft Flight Manual including any limitations • Instructions for Continued Airworthiness • Any other conditions/limitations which the declarant wishes to declare • EASA Noise Record Number
4. Declarant’s Statement
4.1. Declaration of Compliance
I declare that I have the legal capacity to submit this Declaration to EASA and that all information provided in this Declaration form is correct and complete. I hereby declare that the design of the major change/repair described in Section 3 is in compliance with the applicable detailed technical specifications detailed in Section 2.3 and the applicable environmental protection requirements (if applicable) in Section 2.4 in accordance with the compliance demonstration plan detailed in Section 3.4. I hereby declare that no features or characteristics have been identified that, after the major change or repair has been incorporated, may make the aircraft unsafe or environmentally incompatible for the intended use. I hereby commit to undertake the obligations of a Declarant of a Declaration of Design Compliance as detailed in point 21L.A.47 and for major repairs (if applicable) point 21L.A.228 of Annex Ib to Regulation (EU) 748/2012. I declare that I have provided the required information in 3.4 and that it is accurate and complete and indicated where it is not applicable.
Date/LocationNameSignature
Important Note: EASA cannot accept Declarations without signature. Please make sure that you sign the Declaration.
This declaration should be sent by email to: applicant.services@easa.europa.eu

AMC · AMC1 21L.A.107(b) — Regulation (EU) No 748/2012 · ED Decision 2023/013/R · Initial Airworthiness Easy Access Rules · EAR revision 27 Nov 2025

GMGuidance material

GM1 21L.A.107(c)Declaration of design compliance for a major change

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INFORMATION TO BE PROVIDED TO EASA The documents and information that are required to be provided to EASA under point 21L.A.107(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.121(b).

GM · GM1 21L.A.107(c) — Regulation (EU) No 748/2012 · ED Decision 2023/013/R · Initial Airworthiness Easy Access Rules · EAR revision 27 Nov 2025

AMCAcceptable means of compliance

AMC1 21L.A.107(e)Declaration of design compliance for a major change

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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 change 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.

AMC · AMC1 21L.A.107(e) — Regulation (EU) No 748/2012 · ED Decision 2023/013/R · Initial Airworthiness Easy Access Rules · EAR revision 27 Nov 2025

All rules in SECTION A - TECHNICAL REQUIREMENTS

Consolidated from the EASA Easy Access Rules (revision 27 Nov 2025, extracted 17 Aug 2026) for convenience. Not the official publication — verify against the Official Journal of the European Union and the EASA publications before operational use.

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