Part-66 Type Ratings and Aircraft Groups

Passing your modules and getting a basic licence is the first half of becoming a certifying engineer on larger aircraft. The second half is the aircraft rating. If you are researching Part-66 type ratings, you probably want to know three things: whether your aircraft needs one, how type training and on-the-job training work, and what it costs. This guide answers all three, explains aircraft groups and group ratings, covers limitations, and points to the UK type list.

Part-66 Prep is an independent study aid for the basic knowledge modules; we do not provide type training. Rules here are from Part-66 66.A.5, 66.A.45, 66.A.50 and Appendix III, in the EU text consolidated in the EASA Easy Access Rules for Continuing Airworthiness and the retained UK Part-66 on legislation.gov.uk. For licence categories themselves, see the licence categories hub.

Category vs rating: two different things

Your licence category (A, B1, B2, B2L, B3, C) decides what kind of work you may certify: structure and engines, avionics, base maintenance release and so on. Your aircraft ratings decide which aircraft you may certify that work on. A B1.1 licence with no ratings lets you certify nothing on a Boeing or Airbus airliner; add the type rating and you can, within your company authorisation.

There is a third layer: the certification authorisation from your maintenance organisation under Part-145 or Part-CAO. Even with a licence and a type rating, you may only sign for what your organisation authorises. Category A is a special case: it needs no aircraft rating on the licence, and the tasks you may certify are listed on the authorisation instead.

Aircraft groups under 66.A.5

Group	What it includes	Rating needed (B1, B2, C)
1	Complex motor-powered aircraft, multi-engine helicopters, aeroplanes certified to operate above FL290, fly-by-wire aircraft, gas airships other than ELA2, and other types the authority says need a type rating	Individual type rating
2a	Single turboprop aeroplanes, plus turbojet and multi-turboprop aeroplanes the authority classes as lower complexity	Type, manufacturer subgroup or full subgroup
2b	Single turbine helicopters, plus multi-turbine helicopters classed as lower complexity	Type, manufacturer subgroup or full subgroup
2c	Single piston helicopters, plus multi-piston helicopters classed as lower complexity	Type, manufacturer subgroup or full subgroup
3	Piston aeroplanes not in Group 1	Type or full Group 3
4	Sailplanes, powered sailplanes, balloons and airships not in Group 1	Full Group 4 (B2)

The authority can move an aircraft that technically meets Group 1 criteria down to Group 2, 3 or 4 if its lower complexity justifies it, and it decides which airframe and engine combinations make up each type rating. In the UK that list is published by the CAA as SRG 1782, linked from the CAA's type rating page. Check it for the exact rating title before you book a course.

Ratings for B2L and B3

B2L licences cover aircraft outside Group 1, so they carry subgroup and group ratings, never individual type ratings: manufacturer or full subgroup for Group 2, and full group for Groups 3 and 4, based on practical experience. See the B2L guide. B3 has a single rating, "piston-engine non-pressurised aeroplanes of 2,000 kg MTOM and below", also based on practical experience.

How a type rating is earned

Under 66.A.45, endorsing a type rating needs type training to the Appendix III standard, plus on-the-job training if it is your first type in that category or subcategory.

Type training

Appendix III divides it into two parts:

Part	Content	Who delivers it
Theoretical training and examination	The aircraft, its systems, engines and maintenance data, at the depth for your category (B1, B2 or C), ending in exams	A Part-147 organisation, or another organisation with a course directly approved by the authority
Practical training and assessment	A representative cross section of maintenance tasks on the type, with demonstrations using the aircraft, components, simulators or training devices, ending in an assessment	Same

Both parts must be started and completed within the 3 years before you apply for the endorsement. The CAA advises against taking type training long before you hold a licence, because the certificate can run out before you can use it. Category C has theoretical training only.

Differences training covers the gap between two types from the same manufacturer, such as engine variants or closely related models. It is defined case by case, and the new rating is only endorsed if you already hold the base type or have completed its type training.

On-the-job training for your first type

For your first type rating in a licence category or subcategory (except category C), you also need OJT. Appendix III section 6 sets the rules:

• It must be approved by the authority and carried out at, and under the control of, a maintenance organisation approved for that aircraft type.
• It must be started and completed within 3 years before the application.
• It covers a cross section of tasks representative of the aircraft and its systems, simple and complex, each signed by you and countersigned by a designated supervisor, referring to an actual job card or work order.
• It ends with a final assessment by a qualified designated assessor.
• You submit detailed worksheets or a logbook and a compliance report showing how the OJT meets the rule.

The CAA's guidance uses the aircraft type practical experience task list in the AMC to Appendix III as a benchmark: the list has roughly 381 tasks for turbine aeroplanes, 282 for piston aeroplanes, 325 for turbine helicopters and 288 for piston helicopters, and the OJT requirement is about 50% of the representative tasks overall, not 50% in every ATA chapter. Tasks are chosen for their frequency, safety relevance and novelty on that type. The CAA is explicit that a supervisor should not sign a task unless you achieved the required competence.

Key fact: In the UK, OJT done outside the UK only counts if it was carried out by a UK-approved Part-145 organisation whose OJT procedures are approved by the CAA. EASA notes that OJT must be performed on the type you are seeking, with only a limited number of tasks on similar types counted.

The Group 2 and 3 alternative

For Group 2 and 3 aircraft, 66.A.45(d) allows another route: pass the relevant category type examination to the Appendix III standard and, for B1 and B2, demonstrate practical experience on the type covering a representative cross section of maintenance activities. It is useful for lighter aircraft where a full type course may not be available.

Group and subgroup ratings

Instead of collecting types one by one on Group 2 and 3 aircraft, you can earn wider ratings:

• Manufacturer subgroup (B1 and C): meet the type rating requirements on at least two types from the same manufacturer that together represent the subgroup.
• Full subgroup (B1 and C): at least three types from different manufacturers that together represent the subgroup.
• B2 and B2L subgroup ratings: demonstrated practical experience across the subgroup.
• Full Group 3 (B1, B2, B2L, C): demonstrated practical experience. For B1, unless you show the relevant experience, the Group 3 rating carries limitations for pressurised aeroplanes, metal, composite and wooden structures, and fabric-covered metal tube structures.

Limitations and how to remove them

A limitation is an exclusion from your certification privileges written on the licence (66.A.50). Limitations linked to aircraft ratings affect the aircraft as a whole, and are removed by demonstrating appropriate experience or passing a practical assessment by the authority. Some older limitations, from converted national licences, are removed by passing specific modules or part-modules.

In the UK there are two services: removing limitations from the basic category, and removing limitations from type ratings. For basic category limitations the CAA asks for at least 6 months of relevant experience in a CAP 741-style logbook in ATA order, certified exam evidence where a module or part-module is required, and an SRG1029 recommendation from your quality department. The fee is £74 per application as of October 2026, with no extra application fee if you lift type rating limitations at the same time.

Keeping a type rating usable

A type rating has no separate expiry date. It stays on the licence as long as the licence is renewed every five years. What can lapse is your right to use it. Under 66.A.20(b) you may only exercise privileges if you have had 6 months of maintenance experience in line with them in the previous 2 years, and if you are competent to certify on the aircraft concerned.

The EASA Part-66 FAQs explain how this works for ratings. The experience should be on the type itself or on similar types, covering at least one type per aircraft structure (metal, composite or wood). If you lose recency on a type, the ways back include repeating type training, passing a type evaluation with a practical assessment, or, for some licences and groups, showing practical experience across a representative cross section of maintenance activities. Your organisation will also expect type-specific continuation training before it renews your authorisation.

This matters most for engineers who move between fleets. If you hold several ratings but only work on one type for two years, the others stay on the licence, but your organisation should not authorise you on them until you are current again. Keep a record of the types you work on each month; it is the simplest evidence when someone asks.

What a type rating costs

Item	UK CAA (as of October 2026)
Endorsing a type rating	£183 per type
Rolling renewal when the licence is reissued	Prorated renewal charge based on your expiry date
Removing basic category limitations	£74 per application

Source: the CAA type rating and limitations pages and the CAA Scheme of Charges (ORS5). Because adding a type reissues the licence, its five-year validity restarts, which is why the rolling renewal charge applies; the renewal guide explains it.

The big cost is the type course itself. Prices are set by training organisations, vary with the aircraft and category, and are not published by any authority, so we do not quote a figure. Type training on Group 1 aircraft is commonly funded by the employer, and some employers use training agreements that require repayment if you leave within a set period. If you are offered one, read it before you sign. The Part-66 licence cost guide covers the full budget.

Applying for the endorsement in the UK

The CAA process for adding a type, checked October 2026:

1. Hold a UK Part-66 licence in the right category.
2. Complete type training at a UK Part-147 organisation or on a directly approved course (66.B.130), and OJT for a first type.
3. Apply through the aircraft maintenance licence online form on the Customer Portal, uploading ID, certified copies of the type training certificates, certified logbook or OJT worksheets, the OJT compliance report for a first type, and an SRG1029 recommendation.
4. Pay £183 per type plus the rolling renewal charge, and post your original licence to the CAA.
5. A licensing officer assesses the application within 10 working days of receiving the licence.

In the EU you apply to the authority that issued your licence on EASA Form 19. The application guide covers both systems.

Where the basic modules fit

Type training assumes you already have the basic knowledge from your modules. Module 10 in particular covers 66.A.45, aircraft groups, Part-145 certification authorisations and Part-147 type training, so you will meet much of this page again in the exam; the Module 10 questions guide explains how it is examined. For the full route from apprentice to type-rated engineer, see how to become a B1 engineer and the Part-66 B1 licence guide.

What to do next

1. Finish the basic modules for your category; type training cannot be endorsed without a licence. The free licence categories note lists the modules and the aircraft groups.
2. Ask your employer which type they expect you to be rated on, and check its title in the CAA type list (SRG 1782) or your authority's equivalent.
3. Keep your logbook in ATA order now; it doubles as evidence for OJT and limitation removal later.
4. If Module 10 is still ahead, start with the free Module 10 paper 1 and Module 10 quick practice, or the free B1.1 diagnostic for an overview of every module.