Part-CAMO and Part-CAO arrived in the same regulation, on the same day, and organisations still ask which one they are supposed to hold. The honest answer is that they are not two tiers of the same approval. They are two different shapes of organisation, and the choice is usually made for you by the aircraft on your books rather than by preference.

Two annexes, two jobs

Both sit inside Regulation (EU) No 1321/2014, and both were inserted by Commission Implementing Regulation (EU) 2019/1383.

• Part-CAMO is Annex Vc. A continuing airworthiness management organisation. It manages continuing airworthiness. It does not maintain aircraft.
• Part-CAO is Annex Vd. A combined airworthiness organisation. One approval that can both manage continuing airworthiness and carry out the maintenance.

That word “combined” is the whole idea. A Part-CAMO operator needs a separate maintenance organisation — a Part-145, typically — to do the physical work. A CAO can hold both sides of that relationship inside one certificate.

The test that decides it

Part-CAO is not open to everyone. It is aimed at the lighter end: aircraft other than complex motor-powered aircraft. That phrase is a defined term, not a judgement about how big an aircraft looks. It captures, broadly, aeroplanes above a defined maximum take-off mass or passenger-seating threshold, multi-engine turboprops, business and airline jets, and larger multi-engine helicopters.

So the first question is not “which approval suits us” but “what is on our fleet list”:

• Complex motor-powered aircraft, or aircraft operated in commercial air transport by a licensed air carrier, must be managed by an approved Part-CAMO. A CAO is not an option.
• Other than complex motor-powered aircraft, off a licensed carrier’s AOC, can be managed by either — and this is where the choice is real.

This is the same boundary that separates Part-M from Part-ML, which is why the two questions usually arrive together. We cover that split in detail in Part-M or Part-ML? The Line That Decides Which Rules You Follow.

What a CAO can do that a CAMO cannot

A CAO’s privileges, set out in Annex Vd and fixed by the scope of its individual approval, can cover maintenance of aircraft and components, continuing airworthiness management, airworthiness review, and the issue of permits to fly. Not every CAO holds all of them — the approval defines what each organisation may actually do — but the point is that they can sit in one certificate.

For a small maintenance business already turning spanners on light aircraft, that is the attraction. Instead of a maintenance approval plus a contract with a separate CAMO, the whole obligation lives under one roof, with one exposition, one accountable manager and one audit.

Part-CAMO’s advantage runs the other way. It carries no aircraft-complexity ceiling, and it brings the full management-system architecture — safety management and compliance monitoring as an explicit backbone — described in CAMO.A.200. If the fleet might grow into complex or commercial aircraft, a CAMO is the approval that grows with it.

Where both of them came from

Neither annex appeared from nothing, and knowing the lineage is genuinely useful, because older manuals, older auditors and older habits still speak the previous language.

Continuing airworthiness management organisations used to be approved under Part-M Section A, Subpart G — the “Subpart G CAMO”. Its requirements already covered the exposition, nominated personnel, the management of continuing airworthiness and airworthiness review privileges. Alongside it, Part-M Subpart F provided a lighter maintenance organisation approval for smaller aircraft, an alternative to full Part-145 in that segment.

Regulation 2019/1383 replaced both. Subpart G work moved to Part-CAMO, which added the explicit management-system, safety-management and compliance-monitoring spine that Subpart G lacked. Subpart F’s light-maintenance role moved to Part-CAO with maintenance privileges, or to Part-145. The substance carried across; the architecture changed. When you read a CAME today, you are reading the descendant of a Subpart G exposition with a safety management system built into it.

This waypoint from our free introduction course walks that lineage, and it is the clearest three minutes you will spend on why the two annexes are shaped the way they are.

The transition was run through transitional measures in Article 4 of the regulation, amended by Commission Implementing Regulation (EU) 2020/270. Subpart G CAMOs converted to Part-CAMO or Part-CAO; Subpart F organisations converted to Part-CAO or Part-145. Neither organisation type should exist today.

The comparison in one table

Choosing, in practice

If any aircraft you manage is complex motor-powered, or sits on a licensed air carrier’s AOC, the decision is made: Part-CAMO. Nothing else is available to you, and the question is only how to build it.

If your fleet is entirely below that line, ask what you already do. An organisation that maintains aircraft and is being pulled into managing them — or the reverse — is the natural CAO case, because the combined approval removes a contract, an interface and a second set of audits. An organisation that only ever manages, and contracts maintenance out by design, gains less from combining and may prefer the CAMO structure it already resembles.

Then ask where the fleet is going. The complexity ceiling on a CAO is not a formality. An organisation that takes on its first complex motor-powered aircraft, or whose client puts an aircraft onto an AOC, has not just added work — it has moved outside what its approval permits. That is a far more expensive discovery than an approval upgrade planned in advance.

Test how well you know the two approvals with the free Part-M & Part-CAMO quiz: 300 timed questions on EASA continuing airworthiness, with the regulation behind every answer.

Training on this

Our free Part-M and Part-CAMO: An Introduction covers the architecture of Regulation 1321/2014, the annexes and who they apply to, and what a CAMO is responsible for. It takes about 30 minutes, costs nothing, and ends with a certificate. The waypoint above is one of its lessons.

For the regulation covered end to end, see the Part-M and Part-CAMO Familiarisation course. Staff already working in continuing airworthiness who need each process built out in detail should look at the Part-M and Part-CAMO Specialisation course.

Further reading

• Part-CAMO: A Complete Compliance Guide — the full organisation picture once you know which approval you need
• How to Build a CAMO from Scratch — what the approval process actually involves
• How to Write a CAME — the exposition that descends from Subpart G
• Contracted vs Subcontracted CAMO Activities — the interfaces a CAO removes

Frequently asked questions