Part-66L Information

UK continuing airworthiness regulation requires BGA inspectors to hold a UK Part-66 licence with the correct category to certify a release to service for Part-21 sailplanes, powered sailplanes, TMGs and aeroplanes. There is no requirement to hold a Part66L licence to qualify as a BGA inspector – read more about becoming a BGA inspector here.

The following information is published to support BGA inspectors and potential BGA inspectors who choose to qualify for a Part66L licence. Feedback is welcome and in particular with reference to the usefulness or otherwise of the quoted study resources.

Contents

  1. Part66L regulation
  2. Self-study guidance
  3. Theoretical knowledge testing
  4. Experience requirements
  5. Application
  6. Renewing a Part66L licence

1. The Part66L regulation

You can view the Part-66L regulation here.

To apply for a Part66L licence, the applicant is required to:

  1. demonstrate by examination a level of knowledge in the appropriate subject modules in accordance with UK Regulation (EU) No 1321/2014. The examinations can be conducted by specifically authorised invigilators, and
  2. provide practical maintenance experience on operating aircraft in a form acceptable to the CAA and signed by an appropriate signatory.

2. Self-study guidance

Each exam is listed below along with learning objectives and study resources.

The numbers, eg 1L, refer to the module in the Part66L requirements. The learning objectives take the reader to a link to source CAA information.

Note that not all of the following modules are required to qualify for a Part66L. The minimum requirement for Part66L Composite Sailplanes is a pass in 1L, 2L, 3L, 5L, 7L and 12L. For all un-powered sailplanes, a pass is required in 1L, 2L, 3L, 4L, 5L, 6L, 7L and 12L. (reference Part66 Appendix VII — basic knowledge requirements for category L aircraft maintenance licence).

The study resources have been assembled by the BGA to support self-study. As the UK gains experience of these CAA exams, the study resources will be fine tuned.

Question topics are included based on experience to date.

Recording self-study progress

The BGA’s Part66L candidate experience logbook (see below under ‘Experience requirements’) is a helpful method of recording self-study progress.

1L Basic knowledge

1L – learning objectives

1L – study resources:

Aviation Maintenance Technician Handbook – General (FAA-h-8083)

  • Chapter 1, Safety
  • Chapter 3, Mathematics
  • Chapter 5, Physics for aviation
  • Chapter 12, Fundamentals of Electricity and Electronics

AC43-13-1B (FAA) Acceptable methods, techniques and practices – aircraft inspection and repair

  • Chapter 1, Section 2, Health and Safety

2L – Human factors

2L – learning objectives

2L – study resources:

Question topics include:

Why study human factors; healthy BMI range; presbyopia; peer pressure; cold stress; colours most commonly affected by colour blindness; good judgement; satisfactory sleep; problems with inspecting in very bright light.

3L – Aviation legislation

3L – Aviation legislation learning objectives

3L – study resources:

Question topics include:

ELA1 aircraft continuing airworthiness, Part 66 licence validity, where to find instructions for standard repairs, airworthiness limitations, airworthiness maintenance programme requirements, CRS requirements, where to find pilot owner maintenance requirements, deferring defects, responsibility for continuing airworthiness, aircraft records.

4L – Airframe wooden, metal tube and fabric

4L – learning objectives

4L – study resources:

Aviation Maintenance Technician Handbook—Airframe (Volume 1):

  • Chapter 3, Aircraft Fabric Covering
  • Chapter 6, Aircraft Wood and Structural Repair
  • Chapter 8, Aircraft Painting and Finishing

AC43-13-1B (FAA) Acceptable methods, techniques and practices – aircraft inspection and repair

  • Chapter 1 Wood Structure
  • Chapter 2 Fabric covering
  • Chapter 4 Metal structure, welding and brazing
  • Chapter 6 Corrosion Inspection and protection
  • Chapter 7 Aircraft hardware, control cables and turnbuckles

Standard repairs to gliders (BGA)

The BGA glue inspection is now an official source of data

Ceconite manual

Polyfiber manual

Question topics include:

Welded steel tube airframes, welding, fungus infection on a wooden airframe structure, minimum acceptable gradient of grain in wood for an airframe repair, calculating the splice for a tapered beam repair, identifying a heavy landing a compression failure in a beam, stitching a repair to a fabric tear, applying dope to a polyester fabric, Oratex compared to Dacron, inspecting a possible crack in a welded airframe using dye penetrant, repairing corrosion detected on a tube, corrosion protection for the inside of a steel tube, identifying use of urea-formaldehyde glues, specification for aviation grade plywood, use of adhesive lines in plywood when scarfing fasteners.

5L – Airframe composite

5L – learning objectives

5L – study resources:

AC43-13-1B (FAA) Acceptable methods, techniques and practices – aircraft inspection and repair. Chapter 3. Fibreglass and plastics.

  • Repairs
  • Canopy repairs

Aviation Maintenance Technician Handbook (FAA-H-8031 31) —Volume 1 and Volume 2 Chapter 7. Composites.

Standard repairs to gliders (BGA)

Plastic plane patch primer (Ursula Hanle)

Schempp-Hirth repair manual

Slingsby repair manual

Pik30 repair manual

HPH repairing heat damage

Question topics include:

Resins, fillers, inspecting spar root and end fittings, joining two halves of a wing, preparing a hole for repair, effecting repair of a puncture/impact damage less than 5cm close to the main spar near the spar, inspecting a fuselage after a heavy landing using a tap test, use of hand tools when sanding a repair, repairing an FRP balsa sandwich panel which has a puncture penetrating both skins, FRP balsa sandwich panel core repair, balsa use and repair, moulds, gel coat and polyurethan paint, resonance frequency test.

6L – Airframe metal

6L – learning objectives

6L – study resources:

Aviation Maintenance Technician Handbook – General (FAA-h-8083)

Chapter 7 Aircraft Materials, Hardware, and Processes
Chapter 8 Cleaning and Corrosion Control.
Chapter 10 Inspection Concepts and Techniques
Chapter 11 Hand Tools and Measuring Devices

Aviation Maintenance Technician Handbook—Airframe (FAA-H-8083-31 Volumes 1 en 2):

  • Chapter 4, Aircraft Metal Structural Repair
  • Chapter 5, Aircraft Welding
  • Chapter 13, Aircraft Landing gear systems

AC43-13-1B (FAA) Acceptable methods, techniques and practices – aircraft inspection and repair.

  • Chapter 3 Section 2 Metallic sandwich secondary structure repairs
  • Chapter 4 Metal structure, welding and brazing
  • Chapter 5 Non-destructive inspection
  • Chapter 6 Corrosion Inspection and protection
  • Chapter 7 Aircraft hardware, control cables and turnbuckles
  • Chapter 9 Aircraft systems and components

Standard repairs to gliders (BGA)

Question topics include:

Use of duraluminium rivets, rivet clearance, use of lower spec rivets, dimpling, doubler plates, bending, identifying corrosion, dissimilar metal corrosion, nitriding components, cadmium plating, welding, fasteners.

7L – Airframe general

7L – learning objectives

7L – study resources:

Aviation Maintenance Technician Handbook—General:

  • Chapter 6, Weight & Balance
  • Chapter 7, Materials
  • Chapter 9, Fluid lines
  • Chapter 10, Inspection concepts and techniques
  • Chapter 12, Fundamentals of Electricity & Electronics, 12-81, 12-89-94

Aviation Maintenance Technician Handbook (FAA-H-8031 31)

  • Chapter 1, Aircraft structures
  • Chapter 7, Composites, 7-15 Non destructive inspection
  • Chapter 10, Aircraft Instruments
  • Chapter 11, Communication and Navigation
  • Chapter 12, Hydraulic and pneumatic systems
  • Chapter 13 Landing gear
  • Chapter 14 Aircraft Fuel Systems

AC43-13-1B (FAA) Acceptable methods, techniques and practices – aircraft inspection and repair.

  • Chapter 5, Non Destructive testing
  • Chapter 7, Aircraft hardware
  • Chapter 8, Engines, Fuel, Exhaust, propellers, Section 1, 8-8 & 9, Section 2, 4, 5, 6
  • Chapter 9 Aircraft Systems and components; section 1 Landing gear, section 2 Hydraulics, section 3 Emergency equipment, section 4 Cabin interior
  • Chapter 10 Weight & Balance
  • Chapter 11 Aircraft Electrical Systems
  • Chapter 12 Aircraft avionics

Standard repairs to gliders (BGA)

Question topics include:

Fault finding variometers, maximum forward load for instruments when installing or replacing CS22/CS-STAN specified instruments,

8L – Powerplant

8L – learning objectives

8L – study resources:

Aviation Maintenance Technician Handbook— Power Plant Volume 1 and Volume 2.

  • Chapter 9, propellers
  • Chapter 10, Aircraft Instruments and systems, page 3-11
  • Chapter 14 Aircraft Fuel Systems

AC43-13-1B (FAA) Acceptable methods, techniques and practices – aircraft inspection and repair.

  • Chapter 8, Engines, Fuel, Exhaust, propellers, Section 1, 2, 3, 4, 5, 6

Rotax 912 maintenance manual

PA25 owners manual

HPH jet system maintenance

FES manual

12L – Radio, Com, ELT, transponder, instruments

12L – learning objectives

12L – study resources

AC43-13-1B (FAA) Acceptable methods, techniques and practices – aircraft inspection and repair.

  • Chapter 11 Aircraft Electrical Systems

Aviation Maintenance Technician Handbook—Airframe

  • Volume 1 Chapter 9 Aircraft Electrical System

Aviation Maintenance Technician Handbook—Airframe

  • Volume 2 Chapter 11 Aircraft Electrical System

Batteries

Transponders and radios:

Other study resources

3. Theoretical knowledge testing

CAA published Part66L e-exams and module information

Please note that the CAA are responsible for the content of their exams. The Part66L examinations are only available online. The first step is for the candidate to register for the CAA customer portal. Once registered, the candidate can then engage with e-examination process. This candidate user guide explains in detail.

The training organisation is BGA and the reference number is GBR.DTO.0007.

Booked examinations are managed by BGA invigilators* who have been specifically approved by the CAA. Candidates are encouraged to contact the BGA office in good time so that an invigilator can be allocated for an online examination. Candidates are advised to only book exams once they feel fully prepared.

During the exam, those taking the exams can report issues to the CAA.

Further guidance is available from the BGA Chief Technical Officer.

*Current invigilators are Kate Byrne (SGC, Scotland & Borders), Pete Stratten (BGA office), Paul Whitehead (North East), Colin Watt (South East)p

4. Experience requirements

The required practical experience is detailed in Part66L. The BGA is developing a Part66L candidates experience logbook that can be used by prospective Part66L licence holders to record their experience which is confirmed by mentors/supervising Part66L holders who sign in the appropriate box.

A Part66L candidates experience logbook is under development.

5. Application process

Application for a Part66L licence is made direct to the CAA – read more here.

6. Renewing a Part66L licence

A Part66L licence is renewable by the CAA every five years. The BGA recommends that Part66L licence holders do not allow their licence to lapse. A Part66L licence renewal application can be submitted up to 60 days prior to expiry (in exceptional circumstances, the 60 days can be extended to 120 days) with no loss of validity period.

Application to renew a Part66L licence is made direct to the CAA – read more here.