Part-66 Apprentice & OJT Guide: Logging Experience

What Is a Part-66 Apprentice?

A Part-66 apprentice in Europe is someone who is completing an EASA-approved training programme at a maintenance training organisation (MTO, formerly Part-147), or accumulating documented practical experience on the job, working under the supervision of licensed certifying staff. The apprentice is not yet licensed and cannot sign a release to service — but performs hands-on work under the sign-off of a qualified certifying engineer.

Think of the apprenticeship as the bridge between classroom theory and the real-world responsibility of signing maintenance records and releasing aircraft to service under Part-145. During this period, you will build the practical skills, regulatory knowledge, and professional judgment that form the foundation of your entire career as certifying staff.

Who qualifies as a Part-66 apprentice? Any individual enrolled in an EASA-approved MTO programme, or employed in an aircraft maintenance role under the supervision of certifying staff to accumulate the experience required by 66.A.30. You do not need a formal apprentice registration — you register for module exams through your training organisation or national aviation authority, and you document your experience in a logbook countersigned by the certifying staff who supervise you.

For a high-level overview of the full certification process, read our complete guide to becoming an EASA Part-66 licensed engineer in Europe.

Training Paths: EASA-Approved Maintenance Training Organisations

Every Part-66 apprenticeship begins with education — either an MTO programme or structured on-the-job training. EASA approves maintenance training organisations across Europe whose programmes satisfy the basic knowledge requirements for the licence. Graduating from an approved programme, combined with a recognised technical diploma where applicable, reduces the practical experience requirement under 66.A.30 — letting you reach the module exams and the assessment of competence faster.

Here are well-known EASA-approved Part-66 training providers in Europe:

Germany — Lufthansa Technical Training (Hamburg and Frankfurt)

Lufthansa Technical Training is one of the largest and most respected aircraft maintenance training providers in the world, delivering Part-66 programmes in English and German. Their courses combine classroom instruction with extensive practical phases on live aircraft and engines, and graduates are highly sought after by airlines and MROs across Europe.

Spain, Belgium and France — CAE

CAE operates EASA-approved maintenance training academies in Madrid (Spain), Brussels (Belgium) and Paris (France), among others. Their Part-66 programmes are structured around the full licence categories (A, B1.1, B1.3, B2), with strong airline and MRO placement partnerships and modern training facilities.

Germany — IAT (International Aviation Training Academy, Leipzig/Hamburg)

IAT offers EASA Part-66 B1.1 and B2 programmes in both English and German, with a strong emphasis on hands-on practical training. Located close to major German MRO hubs, IAT graduates benefit from direct industry connections and a high placement rate.

United Kingdom — Air Service Training (Perth, Scotland)

Air Service Training (AST) has trained aircraft maintenance engineers for over 90 years, offering EASA Part-66 programmes with extensive workshop and hangar time. Its students work on real aircraft and live engines, and the school maintains strong relationships with regional airlines and MROs.

Ireland — ESM (Dublin)

ESM provides EASA Part-66 theory and practical training at its Dublin campus, with day and evening options that suit working students and career changers. The school is well connected to the Irish and UK maintenance market.

Spain — FTEJerez (Jerez de la Frontera)

FTEJerez, better known for pilot training, also operates an EASA Part-66 maintenance training division. Its programmes are delivered in English, attracting students from across Europe, and benefit from modern facilities in the south of Spain.

Other Notable Training Organisations

• SR Technics (Zurich, Switzerland) — MRO-based Part-66 training with strong practical exposure.
• AMS (Amsterdam, Netherlands) — EASA Part-66 programmes with a focus on B1.1 and B2.
• Technical colleges across the EU — Many national technical colleges and universities of applied sciences run EASA-approved Part-66 tracks alongside engineering degrees.

Most approved programmes follow Part-66 Appendix I and cover the same core modules: mathematics and physics, electrical and electronic fundamentals, materials and hardware, maintenance practices, aerodynamics, human factors, aviation legislation, and the category-specific aircraft and propulsion modules. The key difference between schools is often the quality of hands-on training facilities, the types of aircraft available, and the strength of industry connections for post-graduation employment.

When choosing a training organisation, look for a programme that offers on-site module exam administration and airline or MRO partnerships. These features give you a head start on your exam sequence and often lead directly to full-time employment after graduation.

The Apprenticeship Process: Step by Step

The Part-66 apprenticeship process follows a clear sequence. Here is exactly how it works from start to finish:

Step 1: Complete Your Training Path

Enrol in and graduate from an EASA-approved MTO programme (typically 18-36 months), or begin accumulating practical experience on the job. If you choose the school route, you will receive module certificates and a training record showing the courses completed, and you will qualify for a reduced experience period under 66.A.30.

Step 2: Find Employment in Aircraft Maintenance

Secure a job at a Part-145 maintenance organisation, airline maintenance base, MRO, or general aviation shop. Your employer must have licensed certifying staff on site who can supervise your work and countersign your logbook. Common employers include:

• Major airline maintenance bases (Lufthansa Technik, Air France Industries KLM Engineering & Maintenance, Iberia Maintenance, TAP Maintenance & Engineering)
• MROs (SR Technics, AAR, HAECO Europe, StandardAero, Sabena technics, Aeroplex)
• General aviation maintenance shops and FBOs
• Flight school maintenance departments
• Corporate flight department hangars
• OEM service centres (Airbus, Boeing, Leonardo, Dassault, Gulfstream)

Many apprentices find their first job through school partnerships, career fairs, or direct applications. The demand for maintenance technicians is strong across Europe, but competition for positions at major airlines means you should start your job search early — ideally during your final year of training.

Step 3: Work Under Supervision and Document Your Experience

Once employed, you will work under the supervision of licensed certifying staff who guide your development. Every hour of practical maintenance you perform must be documented in your logbook — 2 years for category A, 4 years for B1.2, 5 years for B1.1/B1.3/B2, and 2 years for B3 — with entries countersigned by the certifying staff who supervised the work. This is the longest phase of the apprenticeship for the OJT route.

During this phase, you will rotate through different areas of the hangar: line maintenance, heavy maintenance, component shop, engine shop, and avionics bay. Each rotation builds different skills and contributes to your overall competency. Your supervising engineers will guide you through progressively more complex tasks as your skills develop.

Step 4: Pass the Part-66 Module Exams

You can — and should — begin taking your Part-66 module exams before you complete your experience documentation. In fact, many apprentices begin taking exams during their final year of training or within the first months of employment. The exams cover the 17 modules of Part-66 Appendix I — from M1 Mathematics to M17 Propeller — with each licence category requiring its own subset of 12 to 14 modules. The pass mark for every module exam is 75%.

For a complete breakdown of every module — including question quotas, time limits, and topic coverage — read our EASA Part-66 module exams guide.

Step 5: Take the Assessment of Competence and Get Licensed

Once you have passed your module exams and completed your experience requirements, B1 and B2 candidates schedule an assessment of competence (66.A.40) with their national aviation authority or an authorised training organisation. You present:

• Your completed logbook (experience countersigned by certifying staff)
• Your module exam certificates (the passing reports from your MTO or CAA exam centre)
• Proof of training (MTO diploma/transcript and recognised diploma, if applicable)
• A valid form of photo identification

If you pass, your national aviation authority issues the Part-66 licence with the categories you qualified for. Important: your licence is issued with the category you tested for (A, B1.1, B1.2, B1.3, B1.4, B2, or B3). You can add categories or subcategories later by taking the additional module exams and assessment. For a detailed comparison of licence categories, see our B1 vs B2 licence category guide.

Step 6: Certification Privileges

Once licensed, you gain the privilege to perform maintenance and sign the release to service within your category — the authority that makes the Part-66 licence the central credential of the profession. B1 holders certify mechanical work, B2 holders certify avionics work, A holders certify a limited set of line tasks, and B3 holders certify small non-pressurised piston helicopters. This is the moment you transition from apprentice to certifying staff, and it marks a significant milestone in both responsibility and earning potential. For a look at how salaries change once you hold that licence, read our EASA Part-66 engineer salary by country guide.

Experience Documentation: How Much, What Counts, EASA Standards

Your experience documentation — maintained in a personal logbook and countersigned by supervising certifying staff — is the single most important record of your apprenticeship. It is the official record of the practical aircraft maintenance experience you performed under supervision. Your national authority reviews it carefully before issuing your licence, and incomplete documentation is a common reason for delays.

How Much Experience Do You Need?

The minimum experience requirements under 66.A.30 depend on your licence category and training background:

• Category A (line maintenance): 2 years of practical experience.
• Category B1.2 (aeroplane piston): 4 years, reduced to 3 years with recognised MTO training.
• Categories B1.1, B1.3 and B2: 5 years, reduced to 3 years with a recognised technical diploma, or 2 years with a recognised technician licence.
• Category B3 (non-pressurised piston helicopters): 2 years of practical experience.

The key takeaway: plan for 2-5 years of full-time work experience if you are not using the MTO route, or 18-36 months of training if you are.

What Counts as Experience?

EASA is specific about what qualifies as creditable experience. The following activities count toward your experience documentation:

• Inspections: Pre-flight, daily, weekly, and phase inspections performed under supervision
• Repairs and modifications: Sheet metal repair, composite repair, component replacement, and modification installations
• Troubleshooting and diagnosis: Identifying faults and determining corrective actions
• Component removal and installation: Engines, landing gear, flight controls, and other line replaceable units
• Rigging and adjustments: Flight control rigging, engine rigging, and system calibrations
• Non-destructive testing (NDT): Dye penetrant, magnetic particle, eddy current, and ultrasonic inspections
• Corrosion control and prevention: Identifying, treating, and preventing corrosion
• Weight and balance: Performing weight and balance calculations and actual weighing of aircraft
• Functional tests: Ground runs, system operational tests, and flight control functional checks

What does NOT count: Classroom instruction, simulators, paperwork-only tasks, cleaning without inspection, and any work performed without the supervision of licensed certifying staff.

EASA Documentation Standards

EASA does not prescribe a specific logbook format, but every experience entry should contain:

• Date of the work performed
• Description of the task (be specific — "inspected landing gear" is too vague; "performed phase inspection on main landing gear shock strut, removed and serviced" is better)
• Aircraft type and registration (e.g., Airbus A320 D-AXXX)
• Hours spent on the task
• The name and licence number of the supervising certifying staff member
• Your signature and your supervisor's countersignature

For a detailed guide to documenting your experience — including common mistakes that delay certification — read our Part-66 experience logbook guide.

Part-66 Licence Categories Explained (A, B1, B2, B3)

One of the most important decisions you will make during your apprenticeship is which licence category to pursue. The category determines the scope of aircraft work you can certify and the career path you will follow.

• Category A (line maintenance): Authorises a limited set of line maintenance tasks — mostly inspections and simple replacements — performed under the supervision of B1 or B2 certifying staff. A good entry point into line operations.
• Category B1 (mechanical): The mechanical licence, with subcategories B1.1 (aeroplane turbine), B1.2 (aeroplane piston), B1.3 (helicopter turbine) and B1.4 (helicopter piston). B1 engineers certify structures, mechanical systems, and engines — the "general practitioners" of the hangar.
• Category B2 (avionics): The avionics licence, covering electrical and electronic systems — communication, navigation, instruments, radar, autopilots, and digital systems. B2 engineers are the electronics specialists of modern aircraft.
• Category B3 (non-pressurised piston helicopters): A combined mechanical/avionics licence for small, non-pressurised piston helicopters, popular in the training and light helicopter sector.

For a full comparison of the categories — including scope, difficulty, exams, and career paths — read our B1 vs B2 licence category comparison guide.

Exam Sequence: When to Take Which Modules

One of the most common questions from apprentices is: when should I take my exams? The answer is: as early as possible. You do not need to wait until you complete your experience documentation. You can sit module exams at any time, and there are strategic advantages to starting early.

Recommended Exam Sequence for Part-66 Candidates

1. Fundamentals modules first (M1-M5): Mathematics, physics, and electrical/electronic fundamentals are the foundation of everything else, and they are the modules you study earliest. Take them while the knowledge is fresh — they are also the shortest exams, making them good confidence-builders.
2. Structures and practices modules next (M6-M10): Materials and hardware, maintenance practices, basic aerodynamics, human factors, and aviation legislation build directly from your daily work — pay attention during your hangar rotations.
3. Category-specific modules (M11-M17): The aircraft and propulsion modules carry the biggest question quotas. Take them when you have the most hands-on exposure and study preparation.
4. Assessment of competence (after all modules + experience complete): Schedule with your national authority once you have passed all required module exams and completed your experience.

For detailed information on the aviation legislation module (M10) specifically, read our EASA Part-66 module exams guide for proven preparation strategies.

Tips for Surviving (and Thriving in) Your Part-66 Apprenticeship

The Part-66 apprenticeship is demanding — physically, mentally, and sometimes financially. Here is practical advice from engineers who have been through it:

1. Find a Mentor Early

The single best thing you can do for your career is find an experienced, knowledgeable certifying engineer who is willing to mentor you. A good mentor will not only supervise your logbook — they will teach you the tricks of the trade, explain why things are done a certain way, and help you avoid common mistakes. Pay attention, ask questions, and show respect for their time. A strong mentor relationship can accelerate your development by years.

2. Network Within the Industry

Aviation is a small world in Europe. Join professional maintenance associations, attend industry events, and connect with other apprentices and engineers. Job opportunities often come through personal referrals, and knowing people at different companies gives you insight into which employers offer the best training and work environment.

3. Develop Consistent Study Habits

Studying for the Part-66 module exams while working full-time is a challenge. Your best strategy is consistency: dedicate 30-60 minutes every day (or every shift cycle) to exam preparation rather than cramming in marathon sessions before each exam. Use your study time wisely by focusing on your weakest modules — this is where adaptive learning tools like Skylicence Europe are particularly valuable.

4. Document Your Experience Religiously

As mentioned above, your logbook is your ticket to certification. Treat it like a legal document — because it essentially is. Log entries daily or at the end of every shift. Be specific about tasks performed. Have your supervising engineer review your documentation regularly. Well-organised records that clearly demonstrate the breadth and depth of your experience will sail through the certification process.

5. Rotate Through Different Work Areas

If your employer allows it, volunteer for rotations through different departments: line maintenance, heavy maintenance, engine shop, component shop, and avionics. Each rotation builds different competencies and makes you a more well-rounded engineer. The authorities look for breadth of experience — you cannot safely certify an aircraft if you have only ever worked in one area.

6. Learn the Regulations Inside Out

The most respected engineers are those who know the regulations — Part-66, Part-145, Part-M/CAMO, and the implementing rules of Regulation (EU) No 1321/2014 — as well as they know the tools in their box. Regulatory knowledge protects you, your employer, and the flying public. Make it a habit to read the relevant EASA regulations and guidance material whenever you encounter a new type of task.

7. Be Patient with Your Progress

The apprenticeship can feel slow, especially in the first year when you are doing basic tasks under constant supervision. That is normal. Every licensed engineer went through the same phase. Trust the process: the experience you accumulate now — even the mundane tasks — builds the foundation for the expert judgment you will need later in your career.

How Skylicence Europe Helps You Prepare for Exams During Your Apprenticeship

Balancing a full-time job with exam preparation is no small feat. That is exactly why Skylicence Europe was built: to help apprentices prepare for the Part-66 module exams efficiently and effectively — whether you are studying before your shift, during a lunch break, or on your days off.

Here is how Skylicence Europe supports your apprenticeship:

• 4,464 questions across the full Part-66 syllabus — covering all 17 modules (Appendix I) and all 8 licence categories. Every question is mapped to the module syllabus so you know exactly which topics you are studying.
• AI-powered adaptive learning — The platform identifies your weak areas and generates targeted practice questions to strengthen them. Instead of reviewing material you already know, Skylicence Europe focuses your limited study time on the gaps that need the most work.
• AI Tutor for complex topics — Stuck on gas turbine theory? Confused by digital techniques? The AI Tutor explains difficult concepts in clear, practical language with real-world context from an experienced engineer's perspective.
• Detailed answer explanations — Every question includes a thorough explanation with references to Part-66 and EASA guidance material, so you learn the why behind each answer.
• Progress tracking by module — You always know exactly where you stand. Track your scores, identify trending weak areas, and measure improvement over time.
• Flexible access — Skylicence Europe works on desktop, tablet, and mobile. Study during your commute, between tasks at work, or at home on your own schedule.

Our students consistently report that Skylicence Europe's targeted approach cuts their exam preparation time by 30-50% compared to traditional methods. That means less time studying and more time focusing on your apprentice work — or simply enjoying your life outside the hangar.

Try free EASA Part-66 practice questions →

Whether you are just starting your apprenticeship or nearing the end of your experience documentation, Skylicence Europe helps you prepare for each module in the right sequence at the right time. Start with the fundamentals and work your way through the full curriculum at your own pace.

Part-66 Apprentice FAQ

How long does it take to become a licensed engineer in Europe?

The total time from starting training to receiving your Part-66 licence is typically 2-3.5 years via the MTO route, or 2.5-5 years via the experience route depending on the licence category. This breaks down as 18-36 months for an MTO programme (followed directly by testing), or 2-5 years of on-the-job experience (with testing interspersed). Candidates who study while working, take exams early, and maintain consistent documentation tend to complete the process faster.

Can I start my Part-66 apprenticeship without attending an MTO?

Yes — Part-66 allows the "experience" route, which requires 2 to 5 years of documented practical experience (66.A.30) depending on your category, without any formal education credit. However, this route is more difficult because you need to learn the theoretical material on your own while working full-time. Most candidates find that completing an MTO programme is significantly faster — recognised training reduces the experience requirement by up to 2 years. The school route is strongly recommended unless you already have substantial aviation maintenance experience.

Do I need to register with an authority before my apprenticeship?

You do not need a formal apprentice registration number. You register for each module exam through your training organisation or directly with your national aviation authority when you are ready to test. Your logbook — countersigned by the certifying staff who supervise you — is your official record of apprenticeship experience.

How much do Part-66 apprentices earn in Europe?

Apprentice and entry-level technician salaries typically range from €1,800 to €3,200 per month, depending on country, employer, and experience level. Technicians at major airlines or large MROs in higher-cost countries (Germany, the Netherlands, Switzerland, the Nordics) tend to earn at the higher end of this range, while those at small GA shops earn closer to the lower end. Shift premiums (evening, night, weekend) can add 10-20% to your base pay. For full details, see our EASA Part-66 salary by country guide.

Can I take my module exams while still in training?

Yes. Part-66 does not require you to complete your training before taking module exams. In fact, taking exams during training — particularly the fundamentals modules — is a smart strategy because the material is fresh and you have dedicated study time. Many MTOs administer the module exams on site and build exam preparation into their curriculum. The sooner you pass your modules, the sooner you can take the assessment of competence once your experience is complete.

What happens if I switch employers during my apprenticeship?

Switching employers is common and does not reset your progress. Your logbook transfers with you. Simply have your previous supervising engineers attest to the work you performed, and continue documenting experience at your new employer. The key is to ensure your new employer has licensed certifying staff who can supervise your work, and to keep your documentation current and complete before leaving any employer.

Can international students become licensed engineers in Europe?

Yes. EU citizenship is not required for the Part-66 licence. International students must have valid student visas for their training programme and work authorisation for on-the-job experience. Non-EU nationals can sit Part-66 module exams and obtain their licence through the national aviation authority of the member state where they qualify — the licence is then valid across all EASA member states, and many employers sponsor work visas for qualified engineers.