21L.A.105 Declaration of design compliance for minor changes

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

IRImplementing rule

21L.A.105Declaration of design compliance for minor changes

(a)Prior to installing or incorporating or agreeing with a production organisation to install or incorporate a minor 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 minor change shall declare that the design of that minor change complies 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declaration of design compliance of the aircraft, unless those detailed technical specifications or parts of them are no longer applicable in accordance with point 21L.B.61 because the Agency has determined that experience from other similar products in service or products that have similar design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 declarant or the organisation that has designed the minor change shall maintain a register of minor changes to the design of aircraft for which design compliance has been declared, and make any declaration made in accordance with point (a) available to the Agency upon request.

IR · 21L.A.105 — 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.105(a)Declaration of design compliance for minor changes

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REQUIREMENTS FOR THE DECLARATION OF A MINOR CHANGE

(a)Applicability of point 21L.A.105 Point 21L.A.105 should be complied with by declarants for the declaration of compliance of a minor change, 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.105(c) for declarations of compliance for minor changes, the substantiating data and the declaration of compliance required by point 21L.A.105(a) should be produced but does 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 change;

(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 change 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.105(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.108(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.108(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 (point (e)) on embodiment/installation instructions.

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

AMC · AMC1 21L.A.105(a) — 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.105(b)Declaration of design compliance for minor changes

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FORM AND MANNER The declarant should complete and file a declaration of compliance for the minor change using the form 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 change, 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

1. Designation
Minor Change	Minor Repair
	Minor Repair

2. Product Identification
Small Aeroplane with a MTOM of 1200Kg or less and a max seating configuration of 2 persons.		Sailplane with a MTOM of 1200kg or less Powered Sailplane with a MTOM of 1200kg or less Balloon designed for no more than 4 persons Hot Airship designed for no more than 4 persons.
2.2 Applicability
2.2.1 Design details	Registered Declaration Number for the original product
	Original Declarant
	Type Name
	Model(s)
2.3 Applicable technical specifications	Please specify the applicable airworthiness code, 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.105 (a)(1) or (2) then this should be indicated here).

3. Description
3.1 Title	Please limit to 40 characters
3.2 Description
3.3 Affected Areas (including manuals)
3.4 Re-Investigations

4. Declarants’ declaration and acceptance of the General Conditions
I declare that I have the legal capacity to make this declaration and that all information provided in this declaration is correct and complete. I hereby declare that the design of the minor 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. I hereby declare that no features or characteristics have been identified that may make the aircraft after the minor change or repair has been incorporated 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.106 of Annex Ib to Regulation (EU) 748/2012. I declare that I have provided the required information and that it is accurate and complete and indicated where it is not applicable.

Date/Location	Name	Signature
This Declaration should be retained by the declarant and made available upon request by EASA

AMC · AMC1 21L.A.105(b) — 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.105(c)Declaration of design compliance for minor changes

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REGISTER OF DECLARATIONS FOR MINOR CHANGES The register that is used by the declarant to record the declarations of design compliance for minor changes 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.

AMC · AMC1 21L.A.105(c) — 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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