If you work in aviation maintenance training, you hear "Part 147" and "Part 66" mentioned almost interchangeably. They are closely linked — but they are not the same thing, and the distinction matters when you are choosing how to manage your training operation.
Part 66: The Licence Regulation
EASA Part 66 defines the aircraft maintenance licence itself. It sets out:
- The categories of licence (A, B1, B2, B3, C)
- The knowledge requirements for each category, broken down into modules (there are 17 modules in the Part 66 basic knowledge syllabus)
- The examination standards that must be met
- The experience requirements for licence issue
- The privileges each licence category grants
Part 66 is primarily addressed to individuals — the engineers seeking a licence — and to the national aviation authorities that issue those licences.
Part 147: The Training Organisation Regulation
EASA Part 147 defines the standards for organisations that are approved to deliver Part 66 training. It covers:
- The facilities, equipment, and instructors an approved MTO must have
- The training programmes that can be delivered (basic training, type training)
- How examinations must be conducted and documented
- How student records must be maintained
- How a Certificate of Recognition (CoR) is issued
- The quality management system the organisation must operate
Part 147 is addressed to maintenance training organisations — the schools, training centres, and MRO-affiliated training departments that deliver the courses and examinations.
How They Relate
Part 66 defines the destination — the licence and what knowledge it certifies. Part 147 defines the approved path to get there — the training and examination an MTO must deliver.
A student attends a Part 147 MTO to complete training and examinations against the Part 66 syllabus. When they pass, the MTO issues a Certificate of Recognition (CoR), which the student presents to their NAA as evidence of training when applying for a Part 66 licence.
What This Means for Training Software
When an MTO evaluates software, both regulations are relevant:
| Feature | Why It Relates to Part 66 | Why It Relates to Part 147 |
|---|---|---|
| Question bank by module | Exam questions must cover the Part 66 syllabus | Part 147 requires examinations are conducted to standard |
| Examination management | Part 66 sets pass marks and resit rules | Part 147 requires exam records are maintained |
| Certificate of Recognition generation | CoR certifies Part 66 training completion | Part 147 defines the CoR format and content |
| Student records | Supports licence applications | Part 147 requires records are retained |
| Attendance tracking | Some programmes require minimum attendance | Part 147 mandates this is monitored |
A training management system that understands both regulations — structuring its question bank by Part 66 module, and its record-keeping by Part 147 requirements — will reduce your administrative burden significantly compared to generic tools.