EASA Part-66 Module 10 Deep Dive: Aviation Legislation, CRS & EASA Form 1

What Is Regulation (EU) No 1321/2014?

Regulation (EU) No 1321/2014 — the regulation on the continuing airworthiness of aircraft and aeronautical products, parts and appliances, and on the approval of organisations and personnel involved in these tasks — is the EU rule that establishes the standards for aircraft maintenance and the licensing of the people who perform it. It is the rule that turns an engineer's knowledge into a legally recognised action: without compliance with its annexes, no maintenance is valid and no aircraft may be released to service.

The Part-66 module exams draw heavily from this regulation. Module 10 (Aviation Legislation, 64 questions in 80 minutes, 75% pass mark) covers the regulation and its annexes as its core subject, and the requirements also appear throughout the technical modules — particularly the release-to-service rules and maintenance records. You can retake a failed module exam by re-registering with an approved maintenance training organisation (MTO) and paying the exam fee again.

The regulation is organised into annexes and subparts, and each annex attracts different numbers of questions — the Part-66 Appendix I syllabus defines a focused scope. Understanding exactly which parts are included and, just as importantly, which ones attract the most questions, is the key to efficient study.

For a broader overview of how legislation fits into the full Part-66 licensing picture, including exam format details and general study advice, read our EASA Part-66 legislation guide. This deep dive goes further, providing granular detail on each annex of the regulation, exact references, and advanced question-type analysis.

Annexes of Regulation (EU) No 1321/2014

The Part-66 Appendix I syllabus specifies that legislation questions draw from the full scope of the regulation, with particular emphasis on Part-66 licensing, Part-145 organisations, Part-M continuing airworthiness, the Certificate of Release to Service, EASA Form 1, and the airworthiness review. Each annex carries a different weight, and within each annex, specific requirements are tested more frequently than others. Here is the complete breakdown.

Annex III (Part-66) — The Aircraft Maintenance Licence

Part-66 defines the aircraft maintenance licence: who may hold it, how it is obtained, and what privileges it grants. Key sections include 66.A.5 (licence categories — A, B1.1, B1.2, B1.3, B1.4, B2, B3), 66.A.20 (privileges — what each category may certify), 66.A.25 (basic knowledge requirements — the 17 modules and the 75% pass mark), and 66.A.30 (experience requirements — for example 5 years for B1.1, B1.3 and B2, 4 years for B1.2, 2 years for A and B3, reduced where recognised training or a recognised diploma is held).

Key points tested:

• Category privileges — B1 covers mechanical maintenance and may sign CRS for the airframe and engine work within its scope; B2 covers avionics; A covers limited line maintenance tasks; B3 covers non-pressurised piston helicopters. Questions may test which category is authorised for a given task.
• Experience requirements — 66.A.30 sets the years of practical experience per category, documented in a logbook and supervised by certifying staff, with reductions for recognised training and diplomas.
• Module structure — The 17 modules of Appendix I (M1 to M17) and the depth levels 1-2-3 required per category.

Study tip: Memorise the eight categories and their scope. The exam frequently asks which category or licence is required for a given task, or how many years of experience are needed for a specific category.

Annex II (Part-145) — Approved Maintenance Organisations

Part-145 governs approved maintenance organisations: the requirements they must meet for approval, the privileges granted by the approval (aircraft maintenance, component maintenance, and/or specialised services), the personnel and facility requirements, the quality system, and the release to service of aircraft and components. Certifying staff in a Part-145 organisation work under the organisation's procedures and authorisation.

Study tip: Questions on this annex usually test the distinction between the organisation's responsibilities (approval, quality system, certifying staff authorisation, EASA Form 1 for components) and the individual engineer's responsibilities (performing the work, signing the CRS within their privileges). Part-145.A.50 governs the CRS for aircraft; Part-145.A.50(b) and the Form 1 govern component release.

Annex I (Part-M) — Continuing Airworthiness

Part-M is one of the most heavily tested annexes. It covers continuing airworthiness management: the obligations of owners and operators (Part-M.A.201), the continuing airworthiness management organisation or CAMO (Part-M.A. Subpart G), the aircraft maintenance programme, the performance of maintenance (Part-M.A. Subpart F), AD compliance, and the airworthiness review (Part-M.A. Subpart I) which ends with the issue of the airworthiness review certificate. It also defines the maintenance records required and the periods for which they must be retained.

Key points tested:

• CAMO role — The CAMO manages the maintenance programme, ensures AD compliance, and organises the airworthiness review. Understanding its duties versus the maintenance organisation's duties is a frequent question.
• Airworthiness review — The review process, the airworthiness review certificate, and its validity period (typically 1 year, with the possibility of a 3-year programme for private aircraft under certain conditions).
• Records — What records must be kept, by whom, and for how long.

Study tip: Build a table of "who does what": CAMO (programme, AD tracking, review), Part-145 organisation (execution of maintenance, CRS, Form 1), certifying staff (signing within privileges). The exam frequently asks which entity is responsible for a given obligation.

Training Organisations (Formerly Part-147, Evolving via Regulation (EU) 2023/989)

The training organisation framework (Annex IV to Regulation (EU) No 1321/2014, formerly Part-147) governs approved maintenance training organisations (MTOs) that deliver the basic training and module exams. Regulation (EU) 2023/989 is transitioning the framework, including the examination rules, into a more integrated system. Module certificates are issued by MTOs after you pass each module exam, and they form the basic knowledge evidence for your licence application.

Study tip: Know that module exams are administered by approved MTOs, that each module has a set question quota and time limit, and that module certificates are the evidence of basic knowledge for the licence application. Also know the distinction between basic training (modules) and type training (on a specific aircraft type, with type ratings).

The Certificate of Release to Service (CRS) and EASA Form 1

The Certificate of Release to Service is the document by which an aircraft is released after maintenance, signed by certifying staff under Part-M.A.801 or Part-145.A.50. It must identify the aircraft, reference the work performed and the data used, and be signed by the authorised certifying staff member. The EASA Form 1 is the equivalent document for components, engines, and propellers released from a Part-145 organisation (or from production under a POA).

Key points tested:

• Who signs what — Aircraft maintenance → CRS signed by certifying staff (B1/B2/A per privileges); component maintenance → EASA Form 1; both reference the approved data used.
• What makes a Form 1 invalid — Incorrect completion, missing signatures, alterations, or release not in accordance with approved data.
• Records — The CRS and Form 1 become part of the aircraft or component records retained per Part-M.

Study tip: Practise the "who signs what" matrix: aircraft line/base maintenance → CRS by B1/B2/A certifying staff; component release → EASA Form 1; airworthiness review → airworthiness review certificate by the CAMO or review organisation. Mixing these up is a classic Module 10 mistake.

Most Tested Subjects Summary

Based on Part-66 Appendix I and extensive candidate feedback, here is a ranked list of the most frequently tested Module 10 topics:

1. Part-66 licence categories and privileges — consistently the most heavily tested single subject
2. The Certificate of Release to Service (Part-M.A.801 / Part-145.A.50 content and signatories)
3. EASA Form 1 (when required, what it certifies, validity)
4. Part-M continuing airworthiness (CAMO, maintenance programme, airworthiness review)
5. Experience requirements (66.A.30) and module requirements (66.A.25)
6. Part-145 organisation requirements (approval, quality system, certifying staff)
7. Airworthiness Directives (compliance and recording)
8. Regulation (EU) 2023/989 and the training organisation framework
9. Airworthiness review certificate (process and validity)
10. Maintenance records (content and retention)

If you master these ten areas, you will have covered the vast majority of Module 10 questions that appear on the exam.

Common Question Types

Module 10 questions fall into three broad categories. Understanding the format of each type will help you approach them strategically on exam day.

1. Direct Regulation Questions

These questions ask you to recall a specific requirement, reference, or detail. They are the most straightforward type and test your ability to remember exact Part-66 or Part-M content.

Example: "Under Part-66 66.A.25, what is the pass mark for all module examinations?"

These are "easy marks" if you have done the memorisation work. The key is not just knowing the reference but understanding what it actually requires. Multiple-choice options for direct questions often include plausible-but-wrong requirements from the same annex.

2. Scenario-Based Questions

These questions describe a real-world maintenance scenario and ask you to identify the correct regulatory response. They are the most challenging question type because they require you to synthesise knowledge from multiple annexes and apply it to a specific situation.

Example: "A B1.1 certifying engineer completes a scheduled maintenance check on an aeroplane operated under Part-M. What document is required before the aircraft can return to service, and who signs it?"

Scenario questions test your ability to navigate the regulatory framework — not just book knowledge. They require you to determine which requirements apply, in what order, and what documentation or authorisation is needed. The best preparation for these questions is working through as many practice scenarios as possible.

3. Classification and Privilege Questions

These questions ask you to classify a task or identify which licence category or organisation is authorised for a given activity — major versus minor repair, B1 versus B2 scope, CRS versus EASA Form 1, CAMO versus Part-145 responsibility. They test your understanding of the boundaries between categories and annexes.

Example: "Replacing a radio navigation unit on a transport-category aircraft is most likely to fall within the scope of which licence category?"

Classification questions require precise knowledge of privileges and scope. The same action might be classified differently depending on the context — for example, servicing a landing gear strut by adding nitrogen is a limited task, but replacing the strut seal is a full maintenance task. These nuances are exactly what classification questions test.

Exam strategy tip: When you encounter a scenario question, read the question first (before the scenario), then read the scenario with the question in mind. This helps you focus on what is relevant and filter out extraneous details that might be included as distractors.

Study Tips for Module 10

Module 10 rewards a specific type of study approach. Here are the strategies that consistently produce the best results:

1. Read the Actual Regulation Text

Do not rely solely on third-party summaries. The exam questions are drafted from the regulatory text, and the precise wording matters. A summary might say "records must be signed," but Part-M specifies exactly what a maintenance record must contain — and those details are what the exam tests. Read Regulation (EU) No 1321/2014 in EUR-Lex (it is free) and focus on the exact wording of the sections listed above.

2. Use the Part-66 Appendix I Syllabus as Your Checklist

The Part-66 Appendix I syllabus lists every subject and depth level for Module 10. Print it out and use it as a checklist. For each learning objective, ask yourself: "Can I explain this to a fellow apprentice without looking at the book?" If you cannot, you have not fully mastered that objective. The syllabus is freely available and is the single most authoritative study resource.

3. Practise with Realistic Mock Exams

The best predictor of exam performance is practice test performance. Take timed mock exams under realistic conditions — 64 questions in 80 minutes, no notes, no interruptions. After each mock exam, review every question you got wrong and every question you guessed on. Understand why the correct answer is correct and why each distractor is wrong.

4. Create a Reference Mnemonic System

The exam requires you to know specific references (66.A.25 for modules and pass mark, 66.A.30 for experience, Part-M.A.801 for CRS, Part-145.A.50 for release). Create mnemonics to lock these in memory — for example, "66.A.30 = thirty months of... experience" (well, five years for B1.1 — the point is to build memorable associations). The more memorable the association, the better it sticks in exam conditions.

5. Study the Interconnections

The annexes are not isolated — Part-66 connects to Part-145 (who works where), Part-145 connects to Part-M (who manages what), and the CAMO connects to both (maintenance programme, AD tracking, airworthiness review). Understanding how the annexes connect is what separates passing scores from high scores. Draw connection diagrams showing how the parts reference each other.

For more advanced study strategies, including time management techniques and the most common mistakes candidates make, see our EASA Part-66 legislation study guide.

Sample Module 10 Exam Question

Here is one realistic Module 10-style question similar to what you will see on the actual exam. Try to answer it before revealing the answer below.

Want more practice questions like this? Try our free Part-66 practice questions — 10 realistic questions covering modules across the Part-66 syllabus, with the same reveal answer format. No signup required.

How Skylicence Europe Prepares You for the Part-66 Module Exams

Skylicence Europe was built specifically to address the unique challenges of the EASA Part-66 module exams. Our platform combines AI-powered adaptive learning with a question bank aligned to Part-66 Appendix I. Here is how it works:

• Adaptive difficulty — The AI identifies your weak areas across all module subjects and generates targeted questions to strengthen them. If you consistently miss questions about the CRS or EASA Form 1, the system will give you more scenarios from those subjects until your performance improves.
• Detailed explanations — Every practice question includes a full explanation of why the correct answer is correct and why each distractor is wrong, with direct regulation references. This transforms every practice session into a learning opportunity.
• Realistic exam simulation — Our timed exam mode replicates the actual module formats: 64 questions in 80 minutes for Module 10, with the same mix of direct, scenario-based, and classification questions.
• Progress tracking — See your performance broken down by module and by individual subject area. Know exactly where you stand and what you need to review next.
• Mobile-friendly — Study on the go. Our platform works on any device, so you can practise during commute breaks, lunch hours, or whenever you have a few minutes.

The Skylicence Europe Module 10 bank is aligned specifically with the Part-66 Appendix I legislation syllabus and covers every subject discussed in this deep dive — from licence categories and privileges to the CRS and EASA Form 1 requirements.

Start your Part-66 exam preparation with Skylicence Europe today →

Putting It All Together: Your Module 10 Study Plan

Here is a suggested 3-week study plan based on the breakdown above:

• Week 1: Read the full text of Regulation (EU) No 1321/2014 on EUR-Lex. Master Part-66 (licence categories, modules, experience) and the structure of the annexes. Create your reference flashcards. Take a baseline practice test to identify initial strengths and weaknesses.
• Week 2: Deep dive into the CRS (Part-M.A.801 / Part-145.A.50) and the EASA Form 1 — the release documents, their content, and who signs them. Spend at least 6 hours on these subjects and the differences between aircraft and component release.
• Week 3: Part-M continuing airworthiness (CAMO, maintenance programme, airworthiness review) and the Part-145 organisation requirements. Study AD compliance and Regulation (EU) 2023/989. Take 2–3 full-length timed mock exams. Review every mistake and drill your weakest subjects.

For a complete overview of all the Part-66 modules and how legislation fits into the broader licensing process, read our Part-66 module exams guide. And to understand the full experience and licensing pathway from start to finish, see our apprentice and OJT guide.

Frequently Asked Questions