CAMO vs Part-145: Understanding the Split
Introduction
If you have spent time around an airline’s technical department, you have probably heard both terms used almost interchangeably: CAMO and Part-145. They are not the same thing, and confusing them leads to real misunderstandings about who is actually responsible for an aircraft’s condition. This article explains the difference between CAMO vs Part-145 in plain terms, using the kind of scenarios that come up on the line every day.
CAMO (Continuing Airworthiness Management Organisation) is the organisation that plans, tracks, and manages an aircraft’s airworthiness over its operational life. A Part-145 approved maintenance organisation is the one that physically performs the maintenance, repairs, and inspections. One thinks and schedules; the other executes with tools in hand.
If you have already read my related article on Continuing Airworthiness Explained, this piece builds on that foundation and focuses specifically on how these two organisations divide responsibility, and why an airline cannot safely operate with only one of them.
What CAMO and Part-145 Actually Do
A Quick Recap: Continuing Airworthiness
Continuing airworthiness is the ongoing process of ensuring an aircraft remains fit to fly throughout its operational life, not just at the point of certification or delivery. This involves scheduled maintenance, defect rectification, compliance with Airworthiness Directives (ADs), and constant monitoring of the aircraft’s condition.
The What Is Continuing Airworthiness? How Aircraft Stay Safe Throughout Their Service Life article covers this concept in depth. Here, we assume you understand that continuing airworthiness is not a single event but a continuous management process, and we focus on the two organisations that carry it out.
CAMO: The Airworthiness Planner
A CAMO, under EASA’s Part-CAMO regulation (formerly Part-M Subpart G before the 2019 restructuring), is responsible for managing the continuing airworthiness of an aircraft. In plain terms, CAMO decides what maintenance needs to happen, when it needs to happen, and confirms that it did happen correctly.
CAMO’s core responsibilities typically include:
- Developing and maintaining the Aircraft Maintenance Program (AMP)
- Monitoring compliance with Airworthiness Directives and mandatory Service Bulletins
- Scheduling maintenance checks based on flight hours, cycles, or calendar time
- Reviewing completed maintenance records for accuracy and completeness
- Issuing the Airworthiness Review Certificate (ARC) recommendation
- Conducting reliability monitoring and analysis
- Managing deferred defects through the Minimum Equipment List (MEL)
- Coordinating with OEMs, lessors, and regulatory authorities on technical matters
A CAMO does not typically touch the aircraft. It manages the paperwork, the planning logic, and the oversight function that ensures maintenance is neither missed nor performed incorrectly.
Part-145: The Maintenance Executor
A Part-145 approved organisation, under EASA’s Part-145 regulation (or an equivalent national approval such as FAA Part 145 repair stations), is authorised to physically perform maintenance, repair, overhaul, and inspection on aircraft, engines, and components.
Part-145’s core responsibilities typically include:
- Performing scheduled maintenance checks (A-checks, C-checks, and similar)
- Rectifying defects reported by flight crew or found during inspection
- Carrying out repairs in accordance with approved data (AMM, SRM, IPC)
- Embodying Service Bulletins and Airworthiness Directives as instructed by CAMO
- Issuing the Certificate of Release to Service (CRS) after work is completed
- Maintaining task cards, work orders, and shop records
- Reporting findings back to CAMO for further evaluation
A Part-145 organisation does not decide what maintenance is due. It receives instructions, in the form of work packages or work orders, and executes them using approved data and licensed personnel.
Why This Split Exists
The separation between planning and execution is not a bureaucratic accident. ICAO Annex 6 establishes the principle that operators must ensure continuing airworthiness through structured management, while the physical maintenance work itself requires separate technical competence, tooling, and facilities.
Keeping these two functions distinct creates a built-in check. The organisation that decides what needs to be done is not the same one certifying that it was done correctly, at least not through the same reporting line. This separation reduces the risk of shortcuts, whether intentional or accidental, and creates a documented handoff at every stage.
In practice, this means:
- CAMO cannot simply skip a scheduled check because it is inconvenient. It must reschedule within regulatory limits and document the justification.
- Part-145 cannot decide on its own to extend an inspection interval. It performs what CAMO has planned, based on the approved maintenance program.
- Both organisations independently retain records, creating traceability if something is later questioned by an authority or an accident investigation.
This is also why, under EASA regulation, a CAMO approval and a Part-145 approval are separate certificates, even when both functions exist within the same airline group. An airline may hold both approvals internally, but the regulation still requires functional separation between the two roles.
CAMO vs Part-145: Side-by-Side Comparison
| Aspect | CAMO | Part-145 |
|---|---|---|
| Primary Function | Plans, manages, and monitors airworthiness | Physically performs maintenance and repairs |
| Regulatory Basis (EASA) | Part-CAMO | Part-145 |
| Regulatory Basis (FAA equivalent) | Continuing airworthiness responsibilities under 14 CFR Part 121/135 operator requirements | 14 CFR Part 145 repair stations |
| Key Output | Aircraft Maintenance Program, ARC recommendation, work orders | Completed maintenance, Certificate of Release to Service (CRS) |
| Typical Personnel | Airworthiness engineers, reliability engineers, planning engineers | Licensed Aircraft Maintenance Engineers (LAMEs), technicians, inspectors |
| Decision Authority | Determines what maintenance is due and when | Determines how the maintenance task is technically executed within approved data |
| Location | Office-based, though often near operations | Hangar, line, or workshop based |
| Documentation Focus | Technical records, compliance status, reliability data | Task cards, work packs, shop findings |
| Accountability | Ensures the aircraft is scheduled correctly and remains compliant | Ensures the work performed meets approved standards |
| Interaction with Authority | Coordinates ARC issuance, submits occurrence reports | Subject to Part-145 audits and approval renewal |
How Information Flows Between CAMO and Part-145
Understanding the relationship between these two organisations is easier through a realistic scenario.
Scenario: A Scheduled C-Check
- CAMO identifies, based on the Aircraft Maintenance Program, that the aircraft is due for a C-check within the next 200 flight hours.
- CAMO compiles the work package, including routine tasks, applicable Airworthiness Directives, open Service Bulletins, and any deferred defects that must be closed during this visit.
- The work package is issued to the Part-145 organisation, whether that is an in-house MRO (Maintenance, Repair, and Overhaul) facility or a third-party contractor.
- Part-145 personnel perform the tasks using approved data such as the Aircraft Maintenance Manual (AMM) and Structural Repair Manual (SRM) where applicable.
- Findings during the check, such as unexpected corrosion or a component nearing its life limit, are documented and reported back to CAMO.
- CAMO evaluates these findings, decides whether additional maintenance action or an engineering disposition is required, and updates the technical records accordingly.
- Once all tasks are complete, Part-145 issues the Certificate of Release to Service (CRS).
- CAMO reviews the completed records for accuracy before confirming the aircraft is airworthy and can return to service.
Scenario: A Deferred Defect
A flight crew reports a minor system fault before departure. The Part-145 line engineer assesses the fault against the Minimum Equipment List (MEL) and determines it can be deferred under specified operating conditions. The defect is logged, the repair category and time limit are recorded, and Part-145 issues a limited CRS reflecting the deferral.
CAMO then tracks this deferred defect to ensure it is rectified within the MEL-specified rectification interval (Category A, B, C, or D, depending on the item). If the interval is approaching expiry, CAMO schedules the repair into an upcoming maintenance visit and notifies Part-145 accordingly.
This example shows the pattern clearly: Part-145 makes the immediate technical judgment at the point of maintenance, while CAMO manages the follow-through over time.
Operational Perspective
From the Airline’s Perspective
The airline, as the aircraft operator, holds ultimate responsibility for ensuring the aircraft is airworthy before every flight. It satisfies this obligation by contracting or maintaining both a CAMO and a Part-145 organisation, whether internally or externally. The airline’s technical management must ensure the interface between these two functions works smoothly, since gaps in communication directly affect dispatch reliability.
From CAMO’s Perspective
CAMO engineers think in terms of compliance status, forecasting, and risk. Their daily concerns include whether the maintenance program is current, whether reliability data suggests an emerging trend, and whether upcoming Airworthiness Directives will affect fleet availability. A CAMO engineer rarely sees the aircraft physically but must understand its condition through documentation.
From Part-145’s Perspective
Part-145 personnel think in terms of task execution, approved data, and physical condition. Their daily concerns include tooling availability, technical data accuracy, and whether the work package received from CAMO is complete and correctly prioritised. Findings during maintenance often prompt direct communication back to CAMO, particularly when something unexpected is discovered.
From the Licensed Aircraft Engineer’s Perspective
The Licensed Aircraft Maintenance Engineer (LAME) signing the CRS is personally accountable for the work performed. This individual accountability is a defining feature of Part-145 operations and is separate from CAMO’s organisational accountability for planning.
From the Flight Crew’s Perspective
Pilots interact primarily with the outcome of both organisations’ work: a serviceable aircraft with valid documentation, or a documented deferred defect they must operate around under MEL conditions. Flight crew do not typically interact with CAMO or Part-145 directly but rely on the technical log as the communication bridge.
From the Civil Aviation Authority’s Perspective
Regulators audit CAMO and Part-145 separately, under their respective approvals, even when both belong to the same airline group. This is because the competencies, oversight requirements, and failure modes differ between planning an airworthiness program and physically executing maintenance tasks.
Common Misconceptions
| Myth | Reality |
|---|---|
| CAMO and Part-145 are just two names for the same department | They are distinct approvals with different regulatory responsibilities, even if housed within the same airline |
| Part-145 decides when maintenance is due | CAMO determines maintenance scheduling based on the approved maintenance program; Part-145 executes it |
| CAMO physically inspects the aircraft | CAMO manages documentation and planning; physical inspection and maintenance are Part-145 functions |
| A licensed engineer can work for either organisation interchangeably without distinction | Roles differ significantly; CAMO engineers typically focus on planning and compliance, while Part-145 engineers hold maintenance licenses tied to specific aircraft type ratings |
| An airline only needs one Part-145 approval or one CAMO approval to operate globally | Approvals are jurisdiction-specific; an EASA Part-145 approval does not automatically satisfy FAA or other national requirements |
| CAMO’s job ends once the maintenance program is written | CAMO continuously monitors reliability, compliance, and emerging findings throughout the aircraft’s operational life |
| Deferred defects are Part-145’s responsibility alone | Part-145 defers the item at the point of maintenance, but CAMO tracks and manages rectification within MEL time limits |
| Outsourcing maintenance to a Part-145 MRO removes the airline’s airworthiness responsibility | The airline, through its CAMO function, retains ultimate responsibility for continuing airworthiness regardless of who performs the physical work |
Frequently Asked Questions
What is the main difference between CAMO and Part-145? CAMO manages and plans an aircraft’s continuing airworthiness, while Part-145 physically performs maintenance, repairs, and inspections. CAMO decides what needs to be done; Part-145 does the work.
Can one organisation hold both CAMO and Part-145 approvals? Yes. Many airlines and MRO groups hold both approvals, but EASA regulation requires clear functional separation between the two roles, even within the same corporate structure.
Who issues the Certificate of Release to Service? The Part-145 organisation issues the CRS after maintenance is completed, confirming the work meets approved standards. CAMO does not issue the CRS but reviews it as part of the airworthiness review process.
Does CAMO ever touch the aircraft directly? No. CAMO’s function is documentation, planning, and oversight. Physical work on the aircraft is performed exclusively by Part-145 licensed personnel.
What happens if CAMO and Part-145 disagree on a finding? Technical disagreements are typically resolved through engineering evaluation, often involving the OEM or the Design Organisation Approval (DOA) holder, since CAMO’s airworthiness determination ultimately governs whether the aircraft can return to service.
Is Part-145 the same as an MRO? Not exactly. MRO (Maintenance, Repair, and Overhaul) is a general industry term for organisations performing maintenance work. Part-145 is the specific EASA regulatory approval that authorises an organisation to perform that work legally. A facility can be described as an MRO and hold a Part-145 approval simultaneously.
Does the FAA have an equivalent split to CAMO and Part-145? The FAA framework differs structurally. FAA-regulated operators (under Part 121 or 135) hold direct responsibility for continuing airworthiness within their own operations specifications, while Part 145 repair stations perform maintenance similarly to EASA Part-145. The FAA does not use a standalone “CAMO approval” in the same regulatory sense as EASA.
Who is responsible if an aircraft is dispatched with an undetected defect? Responsibility depends on where the failure in process occurred. If the defect was missed during maintenance execution, Part-145 accountability applies. If it stemmed from a planning or scheduling gap, CAMO accountability applies. Investigations typically examine both records to determine the root cause.
Why can’t an airline operate with only a Part-145 approval and no CAMO? Without CAMO, there is no structured mechanism to determine what maintenance is due, track compliance, or manage the aircraft’s ongoing airworthiness status. Part-145 alone only addresses execution, not planning or oversight.
Conclusion
CAMO and Part-145 are two halves of the same continuing airworthiness process, but they are not interchangeable. CAMO plans, tracks, and certifies that the right maintenance is scheduled and properly closed out. Part-145 performs that maintenance using approved data and licensed personnel, then certifies the work itself through the Certificate of Release to Service.
The practical takeaway for anyone working in or around this industry: if you are troubleshooting a communication gap in your airline’s technical department, check whether the issue sits on the planning side or the execution side first. Most delays and disputes trace back to a breakdown in the handoff between these two functions, not a failure within either one alone.