On paper, EASA Part-66 and Part-145 create a harmonised system for licensing, competence and maintenance approval across Europe, but does the EASA MOE have a Transparency Gap.
A Part-66 licence should mean the same thing in Spain as it does in Germany.
A Part-145 approval should reflect the same standard whether the aircraft is in Ireland, Malta, or outside Europe under third-country approval.
In practice, the reality is more complex.EASA deliberately writes its framework using Implementing Rules supported by AMC (Acceptable Means of Compliance) and GM (Guidance Material).
These are designed to allow flexibility,authorities can approve Alternative Means of Compliance, local interpretations, and organisation-specific procedures — provided they can justify that safety objectives are met.That flexibility is where variation begins.
Each National Aviation Authority applies its own oversight culture, economic pressures, and interpretations.
Some publish guidance or policy material, but there is no central, transparent register of how each State actually applies Part-66 or Part-145.
The real detail sits inside the Maintenance Organisation Exposition (MOE), approved between the authority and the organisation — and usually not visible to customers.
This is why two organisations can hold identical approvals but operate very different competence models in practice.
Examples many in the industry will recognise:
Category A staff authorised well beyond typical line maintenance intent
Locally approved schemes where mechanics complete only selected Part-66 modules
Partial type training (e.g. hydraulics, flight controls only) with task-limited CRS privileges
Authority-approved task authorisation frameworks that substitute for full licence progression
These arrangements can be fully legal, fully approved, and commercially very attractive.
They reduce training costs, reduce labour costs, and create a workforce whose approvals are often not portable between organisations or States.
Large MROs benefit from stability and lower cost, authorities benefit from attracting business and jobs.
But the consequence is a transparency gap.
Aircraft owners, CAMOs and lessors are often choosing maintenance providers based on the presence of an approval certificate, without being able to see how that approval is actually being exercised in practice.
The system relies heavily on trust: trust in oversight, trust in ethics, trust in competence management.
For those who understand the system deeply, this variation absolutely exists and absolutely influences decisions about where aircraft are sent.
Would greater transparency improve confidence?
Would you support at least parts of the MOE (e.g. competence frameworks, certification models, use of task authorisation) being made public for transparency?
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