Modular licensing for aircraft engineers

We have introduced a flexible pathway for you to get your aircraft engineer licence (a Part 66 licence).

This pathway adopts a modular licensing structure, which allows you to:

  • get a licence sooner with exclusions (limitations)
  • add to the scope of your licence (remove the exclusions). This applies as you get more experience and, where applicable, pass further exams.

Benefits to modular licensing

Modular licensing provides you with greater flexibility to:

  • quickly achieve an initial Part 66 licence
  • gradually increase the scope of your licence as you get more experience and, where applicable, pass further exams.

It is ideal if you:

  • wish to specialise and remain within a certain licence scope
  • do not have a strong interest in other aspects of the full category licence
  • do not have access to work experience for all aspects of a full category licence.

Maintenance organisations also have flexibility to expand the licence scope of their employees to meet the needs of the business.

How modular licensing works

Once you have completed the core basic knowledge exams and experience required for a particular modular licence you can apply for the licence.

We issue the licence with 'exclusions' endorsed on it that define the scope of 'certification privileges' of your licence. If you wish, you can complete further exams and gain further experience to have those 'exclusions' removed.

Understanding exclusions

An exclusion is a limitation applied to the licence by us. It excludes the holder of the licence from certifying maintenance carried out on an aircraft system for which you have not been trained on. For example, no basic knowledge and practical experience on the aircraft system.

Understanding your certification privileges

You can find privileges of your licence under section 66.A.20 of the Part 66 Manual of Standards (MOS).

Within the Part 66 licensing system, there are 2 levels of certification of maintenance. They are:

  • a maintenance certification
  • a certificate of release to service (CRS).

The 2 levels form the basis of the ‘certification privileges’ the holder of a Part 66 licence may exercise.

For more information on licence privileges, refer to Section 3 of Advisory Circular AC 66-08 – Part 66 aircraft engineer licences – privileges

Category B licences

Currently a Part 66 Category B1 (mechanical) licence has the following subcategories:

  • B1.1 aeroplanes - turbine
  • B1.2 aeroplanes - piston
  • B1.3 helicopters - turbine
  • B1.4 helicopters - piston

A Part 66 Category B2 (avionics) licence does not have any subcategories.

In the modular licensing structure you have the following options:

Category B1 licence options:

  • aeroplane airframes only
  • helicopter airframes only
  • powerplant piston engines only
  • powerplant turbine engines only
  • electrical / instrument systems extension.

Category B2 licence options

  • electrical systems only
  • instrument systems only
  • radio systems only.

B1 modular licences — certification privileges and limitations

B1.1 / B1.2 Aeroplanes - airframes only

You may certify completion of maintenance for:

  • all aeroplane mechanical and structural systems.

You are excluded from certifying maintenance for:

  • powerplant (turbine and piston), electrical and avionics systems.

B1.3 / B1.4 Helicopters - airframes only

You may certify completion of maintenance for:

  • all helicopter mechanical and structural systems.

You are excluded from certifying maintenance for:

  • powerplant (turbine and piston) electrical and avionics systems.

B1.2 / B1.4 Powerplant - piston engines only

You may certify completion of maintenance for:

  • all piston powerplant components and systems.

You are excluded from certifying maintenance for:

  • airframe systems, turbine engines, electrical and avionics systems.

B1.1 / B1.3 Powerplant - turbine engines only

You may certify completion of maintenance for:

  • all turbine powerplant components and systems.

You are excluded from certifying maintenance for:

  • excludes airframes systems, piston engines, electrical and avionics systems.

B1 basic knowledge — subject module requirements

You must successfully complete:

  • 8 examinations to qualify for an airframe-only licence
  • 8 examinations to qualify for a powerplant-only licence
  • 7 examinations to qualify for a turbine powerplant-only licence (for aircraft that do not have a propeller, such as turbofan aeroplanes).

B1 modular licence examination requirements

The following table shows which subject modules apply to each B1 modular licence.

Note:

  • Cells with 'Yes' means the subject module applies to the modular licence.
  • Cells with '—' means the subject module doesn’t apply to the modular licence.
Table 1: B1 modular licence examination requirements
Subject moduleB1.1 / B1.2 aeroplane (airframe)B1.3 / B1.4 helicopter (airframe)B1.2 / B1.4 piston (powerplant)B1.1 / B1.3 turbine (powerplant
1. MathematicsYesYesYesYes
2. PhysicsYesYesYesYes
3. Electrical fundamentals————
4. Electronic fundamentals————
5. Digital techniques electronic instrument systems————
6.Materials and hardwareYesYesYesYes
7. Maintenance practicesYesYesYesYes
8. Basic aerodynamicsYesYes——
9. Human factorsYesYesYesYes
10. Aviation legislationYesYesYesYes
11A. Turbine aeroplane aerodynamics, structures and systemsYes (B1.1)———
11B. Piston aeroplane aerodynamics, structures and systemsYes (B1.2)———
12. Helicopter aerodynamics, structures and systems—Yes——
15. Gas turbine engines———Yes
16. Piston engines——Yes—
17. Propeller——Yes (B1.2)Yes (B1.1)

* Optional for turbine powerplants in aircraft without propellers (such as turbofan aeroplanes)

Additional subjects may be undertaken to qualify for licence extensions. You may undertake these at the same time as the exams required in Table 1 or defer until needed.

Optional B1 extension examinations

Some subject modules provide an electrical systems and instrument systems extension to a B1 modular licence. These include:

  • Module 3: Electrical fundamentals
  • Module 4: Electronic fundamentals
  • Module 5: Digital techniques electronic instrument systems

What a modular licence looks like

A modular licence looks much the same as a full licence. It identifies the date of issue, the category or subcategory of licence you hold and the extent of privileges of your licence, defined by the range of exclusions endorsed on your licence.

B2 modular licences — certification privileges and limitations

B2 - Electrical Systems only

You may certify completion of maintenance for:

  • all electrical generation storage and distribution systems. Electrically powered aeronautical products such as starter motors, flap actuation systems etc.

You are excluded from certifying maintenance for:

  • all instrument systems and radio systems.

B2 - Instrument systems only

You may certify completion of maintenance for:

  • all instrumentation systems.

You are excluded from certifying maintenance for:

  • all electrical systems and radio systems.

B2 - Radio systems only

You may certify completion of maintenance for:

  • all radio communication and navigation systems.

You are excluded from certifying maintenance for:

  • all electrical systems and instrument systems.

B2 basic knowledge — subject module requirements

You must successfully complete 10 examinations plus applicable (but not all) topics from module 13 (aircraft structures and systems).

B2 modular licence examination requirements

The following table shows which subject modules apply to each B2 modular licence.

Note:

  • Cells with ‘Yes’ means the subject module applies to the modular licence.
  • Cells with ‘—' means the subject module doesn’t apply to the modular licence.
Table 2: B2 modular licence examination requirements
Subject modulesB2 electrical systems onlyB2 instrument systems onlyB2 radio systems only
1. MathematicsYesYesYes
2. PhysicsYesYesYes
3. Electrical fundamentalsYesYesYes
4. Electronic fundamentalsYesYesYes
5. Digital techniques electronic instrument systemsYesYesYes
6. Materials and hardwareYesYesYes
7. Maintenance practicesYesYesYes
8. Basic aerodynamicsYesYesYes
9. Human factorsYesYesYes
10. Aviation legislationYesYesYes
11A. Turbine aeroplane aerodynamics, structures and systems———
11B. Piston aeroplane aerodynamics, structures, and systems———
12. Helicopter aerodynamics, structures, and systems———
13. Aircraft structures and systems. Topic 13.1 Theory of flightYesYesYes
Topic 13.2 Structures-general conceptsYesYesYes
Topic 13.3 Autopilots (ATA22)—Yes—
Topic 13.4 Communication and navigation (ATA23/34)—YesYes
Topic 13.5 Electrical power (ATA24)Yes——
Topic.13.6 Equipment and furnishings (ATA25)Yes——
Topic 13.7 Flight controls (ATA27)YesYes—
Topic 13.8 Instruments (ATA31)—Yes—
Topic 13.9 Lights (ATA33)Yes——
Topic 13.10 On-board maintenance systems (ATA45)Yes——
Topic 13.11 Air-conditioning and cabin pressurisation (ATA21)Yes——
Topic 13.12 Fire protection (ATA26)Yes——
Topic 13.13 Fuel systems (ATA 28)Yes——
Topic 13.14 Hydraulic power (ATA 29)Yes——
Topic 13.15 Ice and rain protection (ATA 30)Yes——
Topic 13.16 Landing gear (ATA 32)Yes——
Topic 13.17 Oxygen (ATA 35) Yes—
Topic 13.18 Pneumatic/ vacuum (ATA 36)Yes——
Topic 13.19 Water/waste (ATA 38)Yes——
Topic 13.20 Integrated modular avionics (ATA 42)—YesYes
Topic 13.21 Cabin systems (ATA 44)—YesYes
Topic 13.22 Information systems (ATA 46)—YesYes
14. Propulsion — avionic systems—Yes—

How exclusions work

Your modular licence initially will include many exclusions. As you gain further practical experience and pass more basic knowledge exams, you can have these exclusions removed from your licence.

B1 modular licence exclusions

The following table shows exclusions we may apply to a B1 modular licence.

Note:

  • Cells with ‘Yes’ means the exclusion applies to the modular licence
  • Cells with ‘—' means the exclusion doesn’t apply.
ExclusionB1.1 / B1.2 aeroplane (airframe)B1.3 / B1.4 helicopter (airframe)B1.1 / B1.3 turbine (powerplant)B1.2 / B1.4 piston (powerplant)
E1 – Excluding electrical systemsYesYesYesYes
E2 - Excluding mechanical or structural——YesYes
E3 - Excluding powerplant systemsYesYes——
E4 – Excluding electrical subsystems of mechanical, powerplant or structural systems.YesYesYesYes
E5 - Excluding instrument subsystems of mechanical, powerplant or structural systems.YesYesYesYes
E6 - Excluding avionic LRUsYesYesYesYes
E9 - Excluding fabric surfacesYes———
E10 - Excluding wooden structuresYes (B1.2 only)———
E12 - Excluding propellers——YesYes (B1.4 only)

Further exclusions may also appear on your licence. To get these exclusions removed, you will need to successfully complete the relevant CASA knowledge module examination(s) (if applicable) and gain the required practical experience on the excluded system.

B1 modular licence — additional exclusions

The following additional exclusions may be applied to a B1 modular licence, subject to an assessment:

  • E31: Excluding pressurisation systems
  • E33: Excluding supercharging systems
  • E41: Excluding oxygen systems
  • E42: Excluding landing gear retraction systems.

B2 modular licence exclusions

The following table shows exclusions we may apply to a B2 modular licence.

Note:

  • Cells with 'Yes' means the exclusion applies to the modular licence
  • Cells with '—' means the exclusion doesn’t apply.
ExclusionB2 electrical systemsB2 instrument systemsB2 radio systems
E5 - Excluding instrument subsystems of mechanical, powerplant or structural systems.Yes—Yes
E7 - Excluding instrument aspects of avionic systems - ATA 22, 27, 31, 34 and 42Yes—Yes
E8 - Excluding radio aspects of avionic systems - ATA 23, 34, 42 and 44YesYes—

Further exclusions may also appear on your licence. To get these exclusions removed from your licence, you will need to successfully complete the relevant CASA knowledge module examination(s) (if applicable) and gain the required practical experience on the excluded system.

B2 modular licence — additional exclusions

The following additional exclusions may be applied to a B2 modular licence, subject to an assessment:

Note:

  • Cells with ‘Yes’ means the exclusion applies to the modular licence
  • Cells with ‘—' means the exclusion doesn’t apply.
ExclusionB2 instrument systems

B2 radio systems

 

E11 - Excluding audio CVR systems—Yes
E18 - Excluding ADF systems—Yes
E19 - Excluding VOR systems—Yes
E20 - Excluding ILS systems—Yes
E21 - Excluding weather radar systems—Yes
E22 - Excluding ATC transponder systems—Yes
E23 - Excluding radar altimeter systems—Yes
E24 - Excluding DME systems—Yes
E26 - Excluding satellite navigation systems—Yes
E27 - Excluding autopilotsYes—
E30 - Excluding Inertial navigation and reference systemsYes—
E31 - Excluding pressurisation systemsYes—
Last updated:
4 Apr 2024
Online version available at: https://www.casa.gov.au//licences-and-certificates/maintenance-engineers/modular-licensing-aircraft-engineers
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