FAQs – Aircraft Maintenance License

A Part-66 Aircraft Maintenance Licence (AML) is a licence issued by the competent authority in accordance with Annex III (Part-66) to Regulation (EU) No 1321/2014. It confirms that the holder has met the applicable Part-66 requirements for the issue of an Aircraft Maintenance Licence, including the requirements for basic knowledge, maintenance experience and, where applicable, aircraft type or group ratings.

Holding an Aircraft Maintenance Licence (AML) alone does not mean that the holder may exercise certification privileges in all cases without meeting additional requirements. Within a Part-145 organisation, the exercise of such privileges requires a certification authorisation in accordance with point 145.A.35.

Reference: points 66.A.1, 66.A.3, 66.A.20 and 66.B.100 of Annex III (Part-66), and point 145.A.35 of Annex II (Part-145).

The AML Part-66 categories define the scope of certification privileges for aircraft maintenance:

1. Category A – minor scheduled line maintenance and simple defect rectification.
2. Category B1 – maintenance of aircraft structure, powerplant, mechanical and electrical systems, including simple tasks on avionic systems.
3. Category B2 – maintenance of avionics and electrical systems, including related electrical and avionics tasks within mechanical systems.
4. Category B2L – maintenance of electrical and avionics systems within the limits of the system ratings endorsed on the licence.
5. Category B3 – maintenance of non-pressurised piston-engine aeroplanes with an MTOM of 2 000 kg or less.
6. Category L – maintenance of category L aircraft (e.g. sailplanes, powered sailplanes, balloons and airships) within the privileges of the applicable L subcategory.
7. Category C – issuing a CRS for the aircraft as a whole following completion of base maintenance.

Reference: points 66.A.3 and 66.A.20 of Annex III (Part-66).

Ne. Vydání průkazu způsobilosti AML Part-66 potvrzuje, že držitel splnil požadavky Part-66 pro příslušnou kategorii a případně typovou kvalifikaci. Samo o sobě však neopravňuje k vydání osvědčení o uvolnění do provozu (CRS) v organizaci Part-145.

Pro výkon certifikačních práv musí být držiteli organizací údržby vydána certifikační autorizace. Před jejím vydáním organizace ověří, že osoba splňuje všechny příslušné požadavky, zejména požadavky na kvalifikaci, aktuální praxi, odbornou způsobilost a rozsah oprávnění pro konkrétní letadlo nebo letadlový celek.

Reference: bod 66.A.20 přílohy III (Part-66) a body 145.A.30 a 145.A.35 přílohy II (Part-145).

The Civil Aviation Authority of the Czech Republic (CAA) accepts applications for the issue or amendment of a Part-66 Aircraft Maintenance Licence where the applicant meets at least one of the following criteria:

1. is a citizen of the Czech Republic; or
2. is a citizen of another EASA Member State; or
3. holds permanent residence in the Czech Republic; or
4. is, at the time of application, employed by a maintenance organisation approved in accordance with Part-145 or Part-CAO under Regulation (EU) No 1321/2014 and has at least 6 months of recent relevant maintenance experience within the preceding 12 months; or
5. already holds a Part-66 Aircraft Maintenance Licence issued by the Civil Aviation Authority of the Czech Republic.

Where the applicant already holds a Part-66 Aircraft Maintenance Licence issued by the competent authority of another Member State, transfer of the licence under the responsibility of the Czech CAA requires a change of competent authority in accordance with point 66.1(a)(2) of Part-66. Reference: 66.1.(a)(2)

An application for the issue, extension, renewal or other amendment of a Part-66 AML must be submitted using EASA Form 19.

Applications may be submitted:

1. in person to the Civil Aviation Authority,
2. through the applicant’s official electronic data mailbox (where applicable),
3. by post.

The supporting documentation depends on the type of application (e.g. evidence of basic knowledge, practical experience, type training or OJT). The current application forms, list of required supporting documents and information on administrative fees are published on the website of the competent authority – Letecký personál / Technik údržby letadel

Reference: 66.A.10, 66.B.100, 66.B.110, 66.B.115, 66.B.120 and Appendix V to Annex III (Part-66); CAA-ZLP-121.

No. Completion of an approved basic training course under point 147.A.200 in a Part-147 approved maintenance training organisation is not the only route to obtaining an Aircraft Maintenance Licence (AML).

The basic knowledge requirements may be met by successfully passing examinations in accordance with point 66.A.25. These examinations may be conducted by a Part-147 organisation, the competent authority or, in the case of category L, by another organisation accepted by the competent authority.

However, completion of an approved basic training course at a Part-147 approved maintenance training organisation allows the required basic experience to be reduced in accordance with point 66.A.30, provided that the conditions of that provision are met. Reference: 66.A.25, 66.A.30(a) and 147.A.200.

No. The Czech Civil Aviation Authority (CAA) does not conduct Part-66 basic knowledge examinations. These examinations may be taken at a Part-147 approved maintenance training organisation authorised to conduct basic knowledge examinations.

A list of approved Part-147 maintenance training organisations is available on the Czech CAA website – Training Organizations

Reference: point 66.A.25 of Annex III (Part-66), points 147.A.145(a)(iii) and (v) of Annex IV (Part-147), and CAA-ZLP-121.

Compliance with the Part-66 basic knowledge requirements may be demonstrated by:

• a Certificate of Recognition (CoR) on EASA Form 148, if issued by 11 June 2024;
• a Certificate of Recognition on EASA Form 148a issued by a Part-147 approved maintenance training organisation;
• a Certificate of Recognition on EASA Form 148b issued by the competent authority; or
• basic knowledge examination credits under point 66.A.25(d), supported by reference to an examination credit report approved by the competent authority.

Applicants must meet all basic knowledge module requirements applicable to the relevant AML category or subcategory as specified in Annex III (Part-66).

The basic knowledge modules required for each AML category and subcategory are shown in the table below.

Reference: 66.A.25; Appendices I and II to Annex III (Part-66) for categories A, B1, B2, B2L, B3 and C; Appendices VII and VIII to Annex III (Part-66) for category L; Appendix III to Annex IV (Part-147) for EASA Forms 148a and 148b.

For the issue of an AML or the addition of a category or subcategory, the basic knowledge examinations must have been passed within the 10 years preceding the application. The 10-year requirement applies to each individual module examination.

Where an examination was passed more than 10 years before the application, the basic knowledge requirements may be met through examination credits in accordance with point 66.A.25(d). The 10-year requirement does not apply to module examinations already passed as part of another licence category where the licence has already been issued.

Reference: points 66.A.25(c) and 66.A.25(d) of Annex III (Part-66).

Yes. If you decide to continue your Part-66 examination cycle with another Part-147 approved organisation or another competent authority, you must notify the Civil Aviation Authority of the Czech Republic (CAA).

The notification must be sent by e-mail to podatelna@caa.gov.cz and should include the applicant’s identification together with the details of the Part-147 organisations or competent authorities where previous examination attempts have been completed or where future examination attempts will be taken.

The CAA no longer issues approvals or permissions to change examination organisations. The notification is required solely to enable the CAA to monitor the applicant’s examination cycle across multiple organisations and to oversee compliance with the maximum number of examination attempts permitted within a 12-month period.

If all examinations are taken with the same Part-147 organisation or the same competent authority, no notification to the CAA is required.

Reference: CAA-ZLP-121, Section Organisation of Examinations

The required basic maintenance experience depends on:

• the AML category or subcategory;
• the applicant’s technical education;
• whether the applicant has successfully completed an approved basic training course in accordance with point 147.A.200.

The minimum experience requirements are shown in the table below.

Note: For category L, skilled-worker status does not provide a reduction of the basic experience requirement; the applicable duration is specified separately in point 66.A.30(a)(2b). Where the one-year experience route is used, the limitation specified in point 66.A.45(h)(ii)(3) is endorsed on the AML.

An approved basic training course under point 147.A.200 should not be confused with preparatory courses for Part-66 examinations. Such preparatory courses alone do not qualify for a reduction of the required basic maintenance experience.

Reference: point 66.A.30(a) and AMC1 66.A.30(a) of Annex III (Part-66), point 147.A.200 of Annex IV (Part-147), and CAA-ZLP-121.

A skilled worker in a technical trade is a person who has successfully completed training acceptable to the competent authority in the manufacture, repair, overhaul or inspection of mechanical, electrical or electronic equipment. The training must also include the use of tools and measuring equipment.

For the purpose of reducing the practical experience required by Part-66, the Civil Aviation Authority generally considers technical education in aviation, mechanical engineering or electrical engineering, including practical manual training, to be relevant.

Whether a particular qualification is considered acceptable under Part-66 is assessed individually by the CAA based on the supporting documentation provided.

Reference: 66.A.30(a), AMC1 66.A.30(a), point 2, AMC 66.B.100, CAA-ZLP-121.

When applying for the initial issue of an Aircraft Maintenance Licence (AML), at least one year of the required maintenance experience must be recent experience on aircraft relevant to the licence category or subcategory applied for.

Recent maintenance experience means that:

• at least 6 months of the required experience must have been gained within the 12 months preceding the application; and
• the remaining at least 6 months must have been gained within the 7 years preceding the application.

When applying for the addition of a category or subcategory to an existing AML, the required recent maintenance experience may be less than one year but shall not be less than 3 months. The amount of recent experience required depends on the differences between the category or subcategory already held and the one applied for.

All required maintenance experience must have been gained within the 10 years preceding the application. Reference: points 66.A.30(d) and 66.A.30(f) and AMC 66.A.30(d) of Annex III (Part-66).

The requirements for obtaining an aircraft type rating depend on the aircraft group and the licence category.

For Group 1 aircraft, an aircraft type training course is required for endorsement of the aircraft type rating. The type training consists of theoretical and practical elements; the practical element is not required for category C.

For the endorsement of the first aircraft type rating within a given AML category or subcategory, except category C, On-the-Job Training (OJT) is also required in accordance with point 66.A.45(c) and Appendix III to Part-66.

For Group 2 and Group 3 aircraft, the aircraft type rating may be obtained by completing aircraft type training or, where permitted by point 66.A.45, through an Aircraft Type Evaluation. Reference: point 66.A.45, GM1 66.A.45 and Appendix III to Part-66.

The type training course must have been started and completed within the three years preceding the application for the endorsement of the aircraft type rating in the Aircraft Maintenance Licence (AML).

If the application is submitted after this period, the aircraft type training cannot be accepted for the endorsement of the aircraft type rating. The three-year period concerns the use of the type training for the rating endorsement; once the rating has been endorsed on the AML, its validity is not limited by this three-year period. Reference: point 66.A.45 and Appendix III, point 1 to Annex III (Part-66).

Not always. Under point 66.A.45(c), OJT is required for the endorsement of the first aircraft type rating within a given AML category or subcategory, except category C.

For a subsequent aircraft type rating within the same category or subcategory, OJT is normally not required.

OJT must comply with Appendix III, Section 6 to Part-66. The list of OJT tasks and the programme must be accepted before the OJT starts by the competent authority that issued the AML. Reference: point 66.A.45(c), GM1 66.A.45 and Appendix III, Section 6 to Annex III (Part-66).

Yes. The theoretical and practical elements of aircraft type training do not have to be completed by the same organisation. Each element must independently comply with Appendix III to Part-66 and be conducted by a maintenance training organisation appropriately approved under Part-147 or, where conducted by another organisation, be directly approved by the competent authority in accordance with point 66.B.130. Reference: Appendix III to Part-66 and point 66.B.130 of Annex III (Part-66).

Although all three relate to practical maintenance activities, they serve different purposes.

Basic Experience

Basic experience is one of the requirements for the initial issue of an Aircraft Maintenance Licence (AML). The required duration depends on the licence category and on the applicant’s previous technical training or completion of a Part-147 approved basic training course.

Practical Type Training

Practical type training is the practical element of aircraft type training for a specific aircraft type. Its purpose is to develop practical maintenance skills on that type and to meet the standard of Appendix III to Part-66. Where practical type training is conducted by a Part-147 organisation, successful completion is evidenced by the applicable Certificate of Recognition.

On-the-Job Training (OJT)

On-the-Job Training (OJT) is training on a particular aircraft type in a real workplace. It is conducted at one or more maintenance organisations appropriately approved for maintenance of that aircraft type; one of those organisations controls the OJT. Under point 66.A.45(c), OJT is required for the endorsement of the first aircraft type rating within a given AML category or subcategory, except category C. Its purpose is to provide experience in maintenance best practices and correct release-to-service procedures; successful completion includes a final assessment.

Reference: points 66.A.30 and 66.A.45(c), and Appendix III, points 1 and 6 to Annex III (Part-66).