Certifying Staff — Maintenance
Part-66 (CAR 66) and the aircraft maintenance licence — categories A, B1, B2, B3 and C, the sub-categories, knowledge/experience/type-training requirements, recency and CRS privileges.
Certifying staff — summary notes
Free- Part-66 (CAR 66 for the GCAA) sets the Aircraft Maintenance Licence (AML) — the qualification a person must hold to certify maintenance and issue a Certificate of Release to Service (CRS).
- Licence categories: A — line maintenance certifying mechanic, for minor scheduled line maintenance and simple defect rectification within the tasks specifically endorsed. B1 — mechanical: structure, powerplant and mechanical/electrical systems, plus avionic work needing only simple tests. B2 — avionic: avionic and electrical systems. B3 — piston-engine non-pressurised aeroplanes of 2000 kg MTOM or below. C — base maintenance, issuing the CRS for the whole aircraft after base maintenance.
- Sub-categories reflect the aircraft: B1.1 aeroplanes turbine, B1.2 aeroplanes piston, B1.3 helicopters turbine, B1.4 helicopters piston.
- Three things are needed for the licence: basic KNOWLEDGE (the Part-66 module examinations, this syllabus), EXPERIENCE (practical maintenance experience, reduced if training is approved), and for signing on a specific type, TYPE TRAINING and a type rating on the licence.
- Recency to exercise CRS privileges: within the last two years the holder must have six months of relevant maintenance experience, or have met the requirements for issue of the relevant privileges. Continuation training keeps knowledge current.
- The CRS is the licensed person's statement that the recorded work was done to approved data and the aircraft/component is fit for service; the holder must only certify within the scope and ratings the licence and the organisation's approval permit.
- ⚠ Exam trap: B1 is mechanical, B2 is avionic — and a Category C engineer issues the base-maintenance CRS for the whole aircraft, whereas A/B1/B2 support line and component work. Recency is 6 months of experience in the preceding 24 months.
- Categories
- A line · B1 mechanical · B2 avionic · B3 light piston aeroplane · C base
- B1 sub-categories
- B1.1 aero-turbine · B1.2 aero-piston · B1.3 heli-turbine · B1.4 heli-piston
- Recency
- 6 months relevant experience within the preceding 24 months
- B3 scope
- piston, non-pressurised aeroplanes ≤ 2000 kg MTOM
An engineer needs to certify avionic (autopilot and radio) system work on an aircraft type. Which licence category and additional qualification are required?
A Category B2 licence covers avionic and electrical systems, and to certify on that specific type the licence must carry the appropriate type rating gained through approved type training. Holding B2 alone, without the type rating, does not permit certifying that type.
A licensed engineer has done no maintenance for the past 30 months but holds a valid, in-date licence. Can they exercise CRS privileges?
No. Even with a valid licence, the recency rule requires six months of relevant maintenance experience within the preceding two years. Having done none for 30 months, they must regain recent experience (e.g. under supervision) before exercising certification privileges.
Part-66 licence concept map
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