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HKAR-66 Aircraft Maintenance Licence

Introduction

The information below helps new applicants understand the experience and examination requirements for a HKAR-66 licence. As such it is a guide only and readers should refer to HKAR-66 for the detailed requirements before applying. The effective and compliance dates of HKAR-66 are 1 April 2002 and 1 April 2004 respectively. HKAR-66 is available from the Flight Standards and Airworthiness Division of Hong Kong Civil Aviation Department (CAD).

Licence Structure

HKAR-66 is a set of requirements for the qualification of aircraft maintenance staff by the issue of an Aircraft Maintenance Licence. Whilst this licence is intended to be used as the basis for a HKAR-145 Approved Maintenance Organisation to issue a Certification Authorisation, the "basic" element of the licence may be considered as providing a qualification in aircraft maintenance that demonstrates the achievement of an underpinning level of knowledge and competence. HKAR-66 is applicable to the release to service of aeroplanes and helicopters for all weights.

The licence is divided broadly between Mechanical and Avionic trade disciplines although in view of the various technologies and combinations applicable to certain aircraft the Mechanical licence category is further subdivided. In addition there are various levels within the licence, which allow the holder to be authorised to perform certain roles within line and/or base maintenance. These reflect different levels of task complexity and are supported by different standards of experience and knowledge. There is however no reason why an individual cannot hold a combination of licence categories.

The three levels within the licence are:

Category A	- Line Maintenance Certifying Mechanic
Category B1	- Line Maintenance Certifying Engineer (Mechanical)
Category B2*	- Line Maintenance Certifying Engineer (Avionic)
Category B3	- Simple Light Aeroplane Maintenance Certifying Engineer
Category C	- Base Maintenance Certifying Engineer

Category A

A Category A Licence is intended to be the basis for Limited Authorisation allowing an experienced and knowledgeable mechanic to be authorised to certify certain simple inspections and routine tasks. It is not intended that the Category A licence is used alone to support line maintenance activities. The Category A licence does not carry any type ratings but, following appropriate task training within a HKAR-147 or HKAR-145 approved organisation, may be used as the basis for a certification authorisation for certain prescribed tasks.

The Category A Licence is divided into sub-categories; however there is no avionic specific sub category A since the majority of the tasks are either mechanical or electrical in nature. Personnel who have either existing experience or are taking a course of approved training which is of an avionic bias may still qualify for Category A in an appropriate sub category subject to variations in experience or knowledge requirements which apply in such cases. The Category A "basic" licence represents an underpinning level of knowledge and competence upon which to build task training.

The sub categories for Category A - Line Maintenance Certifying Mechanic are:

Sub Category	A1 -	Aeroplanes Turbine
	A2 -	Aeroplanes Piston
	A3 -	Helicopters Turbine
	A4 -	Helicopters Piston

The experience requirements vary according to the amount and type of training received but must be relevant to the sub category of licence and must satisfy certain criteria in respect of recency. The experience for Category A is as follows:

• 3 years - where no previous experience or formal training has been achieved.
• 2 years - where the applicant has completed a training considered relevant by the Director- General as a skilled worker, in a technical trade.
• 1 year - where the applicant has satisfactorily completed a HKAR-147 approved course of basic training in Category A, B1 or A combined with B2*.

Category B

The Category B Licence will be the mainstay licence qualification for aircraft maintenance staff under the Hong Kong Aviation Requirements. Category B licence are available in both mechanical and avionic disciplines with sub categories as for Category A. Although primarily for line maintenance use at Engineer level, it is intended that certain base maintenance staff who do not issue a Certificate of Release to Service (CRS), but who contribute to the final CRS issue by the Category C engineer, will also be required to hold a Category B1 or B2* licence as appropriate.

The sub categories for Category B Line Maintenance Certifying Engineer/Base Maintenance Engineer are:

Sub Category	B1.1 -	Aeroplanes Turbine
	B1.2 -	Aeroplanes Piston
	B1.3 -	Helicopters Turbine
	B1.4 -	Helicopters Piston
Category	B2* -	Avionics (no further sub division)
Category	B3 -	Simple Light Aeroplane (no further sub division)

Category B1 is mechanically orientated and covers aircraft structure, airframe systems, engines and propellers or rotors as appropriate. The licence holder will also be able to certify all electrical work including power and distribution systems and control and indication systems for systems within their privileges. Additionally a capability for authorisation for the replacement of avionic line replaceable units, requiring simple tests to prove serviceability, may be held.

Category B2* is avionic biased, covering ATA Chapters 22 - Autoflight, 23 - Communications, 31 - Instruments, 34 - Navigation and 45 – On Board Maintenance Systems and confers privileges similar to those of the mechanical engineer to cover electrical power and distribution and control and indication systems associated with avionic systems.

There is a degree of overlap where both category B1 and B2* can work and certify. There are also areas and systems where avionic and mechanical engineers must work together to effect complete certification of flying controls and the interface to an autopilot and autoland system. The inclusion of electrical privileges for power distribution and control in both licence disciplines reflects the philosophy that the licence holder becomes self supporting for many tasks rather than relying on the involvement of other staff.

The wider privileges of the Category B licence and the role of the Engineer in defect diagnosis and rectification and system inspection require a more detailed knowledge than that for Category A. This is implemented by a longer period of experience and by examination at a higher level generally than for Category A. The experience required for Category B2* and subcategories B1.1 and B1.3 is as follows:

• 5 years - where no previous experience or formal training has been achieved.
• 3 years - where the applicant has satisfactorily completed a training considered relevant by the Director-General as a skilled worker, in a technical trade.
• 2 years - where the applicant has satisfactorily completed a HKAR-147 approved course of basic training at Category B1 or B2* level.
• 3 years - where the applicant has completed a training acceptable to CAD for a graduated candidate holding an appropriate engineering degree.

The experience required must be practical maintenance experience of operating aircraft appropriate to the licence category of sub category being applied for.

A Category B1 or B2* licence is issued in the appropriate sub-category or category for which the applicant has met the relevant requirements. The licence may be endorsed with type ratings when additional training, examination and experience requirements have been satisfied.

Category B3 is also mechanically orientated and covers those systems as for B1. However, B3 licence is specifically used for the simple light aeroplane, which means un-pressurised piston-engine aeroplane with a maximum take off mass less than 5700 kg and not fitted with a full authority coupled autopilot/flight director. HKAR-145 does not require a Category C certifying staff for the certification of simple light aeroplanes as Category B3 covers all maintenance.

Category C

The Category C licence is considered more of a qualification related to the management of maintenance during base maintenance. It is not a licence which allows the holder to perform detailed inspections, diagnosis and replacements which collectively make up a base maintenance input. The Category C certifier will be supported by appropriately qualified B1 and B2* engineers who carry out these tasks and who verify and sign that they have been completed properly. The Category C licence is intended to be used to certify the process of maintenance, built upon the experience and knowledge of the individual and their ability to manage the input. As such, the route to qualification may be either from a mechanical or avionic background as a Category B1 and B2* licence holder or the equivalent position in base maintenance, a base maintenance engineer/technician.

An alternative qualification path is available based on a qualification at degree level in an appropriate discipline acceptable to the CAD. Acceptance will take into consideration the university which issued the degree and the course content. The degree by itself does not meet the whole qualification as there are additional experience and examination requirements to be satisfied. Graduates may not hold a Category B1 or B2* licence without meeting the 5 years minimum maintenance experience required for that Category.

The experience requirements for Category C are as follows:

• Complex motor-powered aircraft
  - B1.1, B1.3 or B2* licence holders - 3 years experience in line maintenance certification or
  supporting the Category C certifier in base maintenance.
  - B1.2 or B1.4 licence holders - 5 years experience in line maintenance certification of supporting the Category C certifier in base maintenance.
• Other than complex motor-powered aircraft
  - B1.1, B1.3 or B2* licence holders - 3 years experience in line maintenance certification or supporting the Category C certifier in base maintenance.
• Graduates
  - 3 years experience in a civil aircraft maintenance environment including six months observation of or participation in base maintenance tasks. Applicants via this route will still have to satisfy either the B1 or B2* knowledge requirements.

Knowledge Requirements and Examinations

The knowledge requirements are shown in modular format in HKAR-66 Appendix 1.

Unless qualifying for exemptions, all licence applicants will have to sit the appropriate examinations. These will consist of various modular examinations in multi choice question format, intended to sample the knowledge across the appropriate syllabus, and an essay paper to verify the candidate's use of written English. The content of the examinations varies both in the range and complexity according to licence category. Applicants intending to apply for a Category A licence may wish to consider taking examinations at Category B level to avoid having to retake examinations at the higher level later provided that they are able to meet the higher experience requirements within the time limit allowed after passing the examinations. The essay examination is required for licence issue only.

Table 1 Syllabus subject modules

The multi-choice examinations are arranged according to the modules shown in Tables 1 and 2. Examinations are to be conducted by CAD. Candidates must achieve a minimum of 75% in any examination to pass. Modules may be taken singly or in combinations in any order. While an incremental approach may appear more attractive, it may ultimately prove more expensive and time consuming. Once passed, modules are held in credit for a period of 10 years. If all the modules required for licence issue and the appropriate experience are not gained during this period with a successful application for licence issue being made, the examinations have to be repeated. Seventy five seconds are allowed for each multi choice question. Essay papers will consist of four questions, with 20 minutes allowed for each question, drawn from the subjects in modules 7, 9 and 10.

Table 2 Syllabus module applicability

* This module is not applicable to Category A

Aircraft Type Endorsements

Holders of HKAR-66 Aircraft Maintenance Licences in Category B1, B2*, B3 and C may apply for inclusion of an Aircraft Type Rating subject to meeting certain requirements. These are the completion of a HKAR-147 Approved Type Training Course on that type OR an aircraft type training approved by the Director-General of CAD, covering the subjects appropriate to the licence category being endorsed and those topics listed in HKAR 66.45 and the associated AMC/GM. A minimum period of practical experience is required on the aircraft type prior to application.

Type training for Category C differs from that required for Category B1, B2* or B3. Category C type training may be at a general level providing the applicant has previously attended and passed at least one full training course to B1 or B2* level on an aircraft type of a similar technology. Practical training is not normally required. Category C type training will not therefore qualify for type endorsement in Category B1 or B2*. Type courses at Category B1 or B2* level may also allow the licence holder to qualify for Category C level at the same time, providing they already hold a Category C basic licence. CAD will endorse type ratings on HKAR-66 licences.

Licence Certification Privileges

A type rated HKAR-66 Aircraft Maintenance Licence normally does not confer any certification privileges on the holder in their own right. Such licence must be used in conjunction with a HKAR-145 certification authorisation.
However, in minority of cases, a type rated HKAR-66 Aircraft Maintenance Licence may be used to make certification(s) where the licence is endorsed to permit this.
Note: A HKAR-66 Aircraft Maintenance Licence can be issued without any aircraft type ratings, but it should be remembered that an aircraft type rating is one of the prerequisites for a HKAR-145 certification authorisation. HKAR-145 contains additional requirements to qualify to make certification(s).

Logbooks and records

Whilst not mandatory, CAD advises all candidates to maintain log books or records on a progressive basis to support any subsequent licence application. Entries should be made periodically to show periods of work, the nature of the work, the aircraft type involved and such records should be countersigned by a suitable referee. This may be a supervisor, quality manager or HKAR-66 licence holder. For aircraft type ratings a record of the tasks undertaken on the type being applied for will allow CAD to consider the adequacy of the applicant's practical experience in relation to the requirements of HKAR 66.45. CAD may request details of a candidate's experience for perusal.

Exemptions

There is provision under HKAR-66 for exemptions from some of the knowledge or experience requirements for applicants who have any of the following:

1. Proof of previous qualification as a skilled worker in a trade acceptable to the CAD.
2. An ICAO Aircraft Maintenance Licence.
3. Academic examinations or qualifications recognised or acceptable to the CAD.
4. University degrees in an appropriate discipline and as accepted by the CAD.

Please note that none of these has yet been agreed and an evaluation will be required by CAD before any can be accepted as a standard or exemption. CAD may charge for the cost of any such assessment.

Applications

Those intending to obtain a HKAR-66 licence should determine which examination modules they need to pass at the level appropriate to the licence category sought. They may apply on CAD application form for examination. There is no oral examination. Once all written examinations have been passed, applicant should submit the experience to apply for grant of licence. Examination and grant of Licence application forms are available from Personnel Licensing Office or CAD website. All appropriate sections of the form must be completed: failure to do so will result in the application being rejected. The form must be countersigned by a suitable referee and supported by any certificates of examination, records of experience and proof of other qualifications where exemptions are being claimed. The CAD reserves the right to require additional confirmation of details if necessary.

Enquiries

Any enquiries related to aircraft maintenance licensing may be made to:

Personnel Licensing Office
Flight Standards and Airworthiness Division
Civil Aviation Department
1 Tung Fai Road, Hong Kong International Airport,
Lantau, Hong Kong

E-mail: aml@cad.gov.hk