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21L.B.43 Type-certification basis for a type certificate

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

IRImplementing rule

21L.B.43Type-certification basis for a type certificate

(a)The Agency shall establish the type-certification basis and notify it to the applicant. The type-certification basis shall consist of:

1.the certification specifications for airworthiness designated by the Agency from those applicable to the product at the date of application for that certificate, unless:

(i)the applicant chooses to comply with certification specifications which became applicable after the date of the application; if an applicant chooses to comply with a certification specification which became applicable after the date of the application, the Agency shall include in the type-certification basis any other certification specification that is directly related; or

(ii)the Agency accepts any alternative to a designated certification specification that cannot be complied with, for which compensating factors have been found that provide an equivalent level of safety; or

(iii)the Agency accepts or prescribes other means that demonstrate compliance with the essential requirements of Annex II to Regulation (EU) 2018/1139;

2.any special condition prescribed by the Agency in accordance with point 21L.B.44(a).

(b)The Agency may amend the type-certification basis at any point before the issuance of the type certificate if it 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 type-certification basis that was established and notified to the applicant does not address this unsafe condition.

IR · 21L.B.43 — Regulation (EU) No 748/2012 · Regulation (EU) 2022/1358 · Initial Airworthiness Easy Access Rules · EAR revision 27 Nov 2025

GMGuidance material

GM1 21L.B.43(a)Type-certification basis for a type certificate

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1.INTRODUCTION This GM addresses the type-certification basis for a type certificate (TC).

2.APPLICABLE CERTIFICATION SPECIFICATIONS (CSs) The type-certification basis for a TC consists of the airworthiness CSs that were effective on the date of application and were applicable for the particular certificate.

3.ELECT TO COMPLY (see point 21L.B.43(a)(1)(i)) It is also possible for an applicant to elect to comply with a CS that became applicable after the date on which the applicant has submitted the application. The Agency should assess whether the proposed certification basis is appropriate to ensure that the ‘elect to comply’ proposal includes any other CSs that are ‘directly related’ to one or several of the CSs in it. Directly related CSs are those that are deemed to contribute to the same safety objective by building on each other’s requirements, addressing complementary aspects of the same safety concern, etc. Typically, they are adopted simultaneously with, or prior to, the CSs with which the applicant has elected to comply.

4.EQUIVALENT LEVEL OF SAFETY (see point 21L.B.43(a)(1)(ii)) In cases in which the applicable CSs cannot be literally complied with, either fully or in part, EASA may accept a suitable alternative which provides an equivalent level of safety through the use of appropriate compensating factors. In cases in which the requirements contain not only objectives but also prescriptive parts, an equivalent level of safety may be accepted if: the objectives are met by designs or features other than those required in the CSs; or suitable compensating factors are proposed.

5.ALTERNATIVE MEANS OF COMPLIANCE (see point 21L.B.43(a)(1)(iii)) If the intent of the CSs defined in point 21L.B.43(a)(1) cannot be met, EASA may accept mitigating factors to the CSs, provided that the safety objective is met. In the case of a TC, the alternative means should provide a demonstration of compliance with the essential requirements for airworthiness laid down in Annex II to Regulation (EU) 2018/1139. Note: ‘Alternative means of compliance’ should not be confused with ‘AMC’.

6.SPECIAL CONDITIONS (see point 21L.B.43(a)(2)) The Agency may also prescribe special conditions in accordance with point 21L.B.44. Guidance on special conditions is provided in GM1 21L.B.44.

GM · GM1 21L.B.43(a) — Regulation (EU) No 748/2012 · ED Decision 2023/013/R · Initial Airworthiness Easy Access Rules · EAR revision 27 Nov 2025

All rules in SECTION B - PROCEDURES FOR COMPETENT AUTHORITIES

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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