Regulation (EU) 2020/270
For the purpose of this Part, the competent authority shall be:
1. for the oversight of the continuing airworthiness of individual aircraft and the issue of airworthiness review certificates the authority designated by the Member State of registry;
2. for the oversight of a maintenance organisation as specified in Section A, Subpart F of this Annex (Part-M):
(i) the authority designated by the Member State where that organisation's principle place of business is located;
(ii) the Agency if the organisation is located in a third country;
3. for the approval of aircraft maintenance programmes (‘AMP’), one of the following:
(i) the authority designated by the Member State of registry of the aircraft;
(ii) if prior to the approval of the aircraft maintenance programme the Member State of registry agrees, one of the following:
(a) the authority designated by the Member State where the operator has its principal place of business or, in case the operator has no principal place of business, the authority designated by the Member State where the operator has its place of establishment or where the operator resides;
(b) the authority responsible for the oversight of the organisation managing the continuing airworthiness of the aircraft or with which the owner has concluded a limited contract in accordance with point (i)(3) of point M.A.201.
4. for the oversight of a continuing airworthiness management organisation as specified in Section A, Subpart G of this Annex (Part-M):
(i) the authority designated by the Member State where that organisation's principle place of business is located if the approval is not included in an air operator's certificate;
(ii) the authority designated by the Member State of the operator if the approval is included in an air operator's certificate;
(iii) the Agency if the organisation is located in a third country.
ED Decision 2015/029/R
A competent authority may be a ministry, a national aviation authority or any aviation body designated by the Member State and located within that Member State. A Member State may designate more than one competent authority to cover different areas of responsibility, as long as the designation decision contains a list of the competencies of each authority and there is only one competent authority responsible for each given area of responsibility.
ED Decision 2022/017/R
TRANSFER OF RESPONSIBILITY FOR THE APPROVAL OF THE AIRCRAFT MAINTENANCE PROGRAMME
(a) The aircraft maintenance programme (AMP) may be approved by an authority other than the one designated by the Member State of registry of the aircraft when that Member State concludes a written contract with the Member State of the operator, of the continuing airworthiness management organisation (CAMO) or of the combined airworthiness organisation (CAO) if the conditions of point M.1.(3)(ii) apply. The written contract between the two Member States contains a reference to the aircraft and the competent authorities (CAs), as well as the terms and conditions for the transfer of responsibility between the CAs.
(b) If the responsibility for the approval of the AMP is transferred to the competent authority that is responsible for the CAMO or CAO, that AMP may be approved through an indirect approval procedure (see point M.A.302(c)) that the CAMO or CAO may have prior to the transfer unless otherwise specified by the terms and conditions for the transfer that are referred to in point (a).