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66.A.45 specifies the requirements for adding aircraft type ratings to a Part 66 licence, including the type training course, examination, and practical experience components that must be completed.
What it means in practice
Before you can certify maintenance on a specific aircraft type, that type must be endorsed on your licence. For Group 1 (complex) aircraft, this means completing an approved type training course delivered by a Part 147 organisation or the aircraft type certificate holder, passing a type examination, and accumulating practical experience on the type. The practical experience must include a representative cross-section of maintenance activities relevant to the type.
For Group 2 and Group 3 aircraft, the process can be simpler. A full group or subgroup rating may be endorsed based on appropriate training and experience without requiring a formal type training course for each individual aircraft type. However, for any new type within a group, the licence holder and their organisation should ensure adequate familiarisation before exercising certification privileges.
Key requirements
For Group 1 aircraft type ratings, the approved type training course must cover both theoretical and practical elements. The theoretical element covers the aircraft systems, structure, and powerplant. The practical element involves hands-on tasks representative of the maintenance that certifying staff will be authorising. The type examination must be passed within three years of completing the type training course.
Practical experience requirements for type endorsement vary by licence category. Category B1 and B2 applicants typically need a defined period of practical experience on the specific aircraft type. Category C applicants must demonstrate familiarity with base maintenance on the type. On-the-job training (OJT) structured in accordance with Appendix III to Part 66 is a common way to fulfil the practical experience element for type endorsements.
Common compliance gaps
A recurring issue is the gap between completing a type training course and accumulating the required practical experience. Engineers sometimes complete their theoretical type training but struggle to access sufficient hands-on time on the aircraft before the three-year validity window for the type examination closes. Another gap is inadequate on-the-job training records, where the practical tasks completed are not properly documented against the OJT requirements, making it difficult to demonstrate compliance to the competent authority.
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