UK Part-CAO is a combined Maintenance and Airworthiness Management Organisation Approval for General Aviation Aircraft. A UK Part-CAO organisation may perform both continuing airworthiness management activities and maintenance on aircraft within the scope of UK Part-ML and non-complex aircraft within the scope of UK Part-M (up to 5700 kg MTOW). The approval is limited to aircraft not used by a licenced air carrier.
- Applications for a Part-CAO approval can be made using the online application form.
- Applications should include a Combined Airworthiness Exposition (CAE) and a quality audit to show that your organisation is in compliance with the requirements. The CAE document should be in the format specified in AMC1 CAO.A.025 Combined airworthiness exposition (CAE). The Part-CAO Example Expositions in the section below are in the correct format.
- The Scheme of Charges offers current fee information for Airworthiness, Noise Certification and Aircraft and Aircraft Engine Emissions).
If you need to change your Part-CAO approval, you must notify the Civil Aviation Authority (CAA) of your proposals before the changes take place.
Variation (any variation to the terms of approval needing approval by the CAA)
A Variation to a Part-CAO Approval is a change affecting the information contained in the approval certificate [CAO.A.105 (a) 1.]. Applications for a variation to a Part-CAO approval can be made using the online application form. Applications should include a revised Combined Airworthiness Exposition (CAE) and an internal audit to show that your organisation is in compliance with the requirements. Once your application is accepted you will be contacted by your surveyor to process the variation.
Change (any change to the organisation managed by the organisation)
The following changes require CAA approval or acceptance [CAO.A.105 (a) 2-5]:
- change of CAO.A.035 nominated staff
- changes in the scope of approval related to complete turbine engines
- changes in aircraft subject to Part M regulation
- changes in control procedure set out in the CAE, Section A5
- Acceptance of Airworthiness Review Staff
Civil Aviation Authority (CAA) Light Aircraft Maintenance Programme (LAMP) cannot be used after 24 March 2021. CAA LAMP has been withdrawn. All aircraft within the scope of Part-ML must transfer to a Part-ML-compliant maintenance programme at the next Airworthiness Review.
GR No.17 and GR No.24 have been revised to remove their applicability to aircraft maintained under Part-ML.
Deviations from the Design Approval Holder's Instructions for Continuing Airworthiness (DAH ICA), such as the extension of time between overhaul (TBO) intervals, should be evaluated using a risk-based approach in accordance with ML.A.302.
The risk-based approach should consider aspects such as the operation of aircraft, type of aircraft, hours/years in service, maintenance of the aircraft, compensating measures, redundancy of components, etc.
Alternative tasks or intervals (for example, escalations) to the DAH ICA by the Continuing Airworthiness Management Organisation (CAMO) or Combined Airworthiness Organisation (CAO) do not need to be approved by the Civil Aviation Authority (CAA). Justification of these deviations are to be documented and retained by the CAMO or CAO.
Where an aircraft subject to Part-ML is not used for commercial operations and the owner elects to manage the continuing airworthiness of the aircraft themselves, the owner issues a declaration for the maintenance programme and in this case, no justification of such deviations is required.
Details can be found in Part-ML Paragraph ML.A.302 and AMC1 ML.A.302(c)(3). Owners, operators and approved organisations should ensure they are familiar with the revised regulations as well as the safety implications of any proposed deviations from the DAH ICA.
It is important to note that deviations with respect to tasks classified as mandatory (for example, Airworthiness Directives, requirements specified on the type certificate data sheet, airworthiness limitations) are not permitted.
The following information is intended to provide simple guide to some of the changes in regulations when Part-ML became applicable for Part-CAO and Part-145 organisations maintaining aircraft in accordance with the revised Part-M and Part-ML.
In all cases the UK Regulations and AMC/GM are the definitive documents.
A Part-CAO organisation can maintain and manage aircraft within the scope of Part-ML.
A Part-CAO organisation can also maintain and manage aircraft within the scope of Part-M that are not classified as complex motor-powered aircraft and are not listed in the air operator certificate of an air carrier licensed in accordance with UK Regulation (EC) No 1008/2008.
A full list of aircraft and operations that can only be managed and maintained by Part-CAMO/Part-145 Organisations is in Part M, M.A.201 (e), (f) and (g). Aircraft in this category are not within the scope of a Part-CAO.
These documents have been produced by the UK Civil Aviation Authority (CAA) as examples of a compliant Part-CAO Combined Airworthiness Exposition (CAE) and the associated BCAR A8-24 & A8-25 supplements.
They have been produced with the intent of assisting new applicants and those organisations transitioning from Part-MF & Part-MG to Part-CAO. The notes page at the beginning of each document contains important information to be read prior to use of the content:
If an organisation has aircraft within the scope of Part-M and Part-ML it must have Airworthiness Review staff qualified in accordance with both Part M, M.A.707 and Part-ML, ML.A.904.
If you maintain both classes of aircraft, you need procedures appropriate to each set of regulations. Part-ML does not allow the voluntary application of Part-M requirements to aircraft in the scope of Part-ML.
Use of parts which have been released by a UK Part-CAO (under a component rating) by a UK Part-145 organisation
Parts released by a Part-CAO under a Component rating can be used by a Part-145 organisation, but the components cannot used for aircraft included in Part M, M.A.201 (e), (f) and (g).
This means if an aircraft can only be managed by a Part-CAMO organisation, parts released by a Part-CAO cannot be used.
As it says on the Civil Aviation Authority (CAA) Form 1 “This certificate does not automatically constitute authority to install the item(s).”
This guidance sets out the principles to be used by Part-CAO organisations when installing used components maintained by an FAA Part-145 repair station (USA) that does not hold a CAA Part-145 or Part-CAO approval.
The following conditions must be met:
- the component has a Form 8130-3 (FAA)
- the installer (Part-CAO) has verified compliance with all applicable airworthiness directives
- the installer has verified that the component does not contain repairs or modifications that have not been approved in accordance with UK Part 21
- the installer has inspected the component for satisfactory condition including damage, corrosion, or leakage
- the installer has issued a CAA Form 1
Please note Part-CAO organisations can issue a CAA Form 1 providing they have the appropriate product (Aircraft) rating for the aircraft on which the component is being installed. Individual component ratings (for example, C3: communications and navigation and so on) are not required.
The full text for the UK Continuing Airworthiness Acceptable Means of Compliance and Guidance Material for UK Regulation (EU) No.1321/2014 provides further information.
The Civil Aviation Authority (CAA) template for the Combined Airworthiness Exposition (CAE) does not include a chapter for Occurrence Reporting Procedures.
The UK Occurrence Reporting (OR) Regulation states that each organisation shall establish a mandatory reporting system to facilitate the collection of details of occurrences. However, in many cases small organisations cannot fulfil some requirements of this regulation, for example, a person to handle independently the collection, evaluation, processing, analysis and storage of details of occurrences reported.
One of the key principles of the OR regulation is the obligation for designated persons to report certain occurrences, small Part-CAO organisations should ensure that these responsibilities are fully understood.
In a Part-CAO organisation a designated person is a person who signs an airworthiness review certificate, or a release to service in respect of an aircraft or any equipment or part thereof.
Where organisations are too small to fully comply with all the requirements of the OR regulation, designated personnel should report as individuals until such time as Part-CAO is aligned with OR regulation.
Voluntary reporting systems should accompany the mandatory reporting systems, and both should allow individuals to report details of aviation safety-related occurrences in a timely manner.
All organisations should implement a just culture where occurrence reporting is encouraged, and safety is discussed regularly as tool-box talks or informal meetings.
Just culture means a culture in which front-line operators or other people are not punished for actions, absence or decisions taken by them that are relative with their experience and training, but in which gross negligence, deliberate violations and destructive acts are not tolerated.
A report for an occurrence can also be made and further to this, there is also a list of classifying occurrences (UK Regulation No 2015/1018) that is required to be reported.
CAO.A.100 allows small Combined Airworthiness Organisation (CAO) organisations to replace the quality system with regular organisational reviews subject to the approval of the Civil Aviation Authority (CAA). In small CAO organisations, an organisational review is expected to be less complex than a quality system, however the one principle that both an organisational review and a quality system should have in common is the requirement of independence.
In line with GM1 CAO.A.100(a), the requirement of independence should be established by always ensuring that audits are carried out by personnel who are not responsible for the functions, procedures or products that are audited. In other words, the independence is to be applied to the process of how an organisational review is conducted rather than there being a requirement for an auditor not being connected to the organisation.
In a small organisation consisting of two persons for example, the accountable manager would be the person responsible for the organisational review and the one performing the review, thus being independent from the person responsible for Certifying maintenance or issuing Airworthiness Review Certificates.
A person authorised to issue Airworthiness Review Certificates within the organisation would not be considered independent if they were conducting an organisational review of the continuing airworthiness procedures or maintenance programme approval.
A person Certifying Maintenance within the organisation would not be considered independent if they were conducting an organisational review of maintenance procedures.
Since 01 January 2021 it is only possible to issue a Civil Aviation Authority (CAA) Form 15c for aircraft within the scope of Part-ML (New Issue).
If an aircraft holds a current EASA Form 15b or Form 15c, that has not been extended for either the first or second time, it is possible to extend this ARC until the first and second extensions expire. This is only possible where the aircraft has been continuously managed for the previous 12 months by the Continuing Airworthiness Management Organisation (CAMO) (Subpart MG, Part-CAMO or CAO) granting the extension after ensuring that the other requirements of ML.A.901(c) are also met.
Approved organisations may issue Airworthiness Review Certificates (ARCs) directly using the Word version of Civil Aviation Authority (CAA) Form 15C Issue 2, suitably amended with their approval number, aircraft details and dating protocols.
A copy of the ARC issued or extended for an aircraft must be sent to the CAA: email@example.com within 10 days, as required by ML.A.903 (h).
For those organisations that have been granted the additional privilege to issue Permits to Fly, a copy of the issued CAA Form 20b Permit to Fly will need to be provided to the Civil Aviation Authority (CAA) including the details of the organisation issuing the permit to fly, a copy of the approved flight conditions and any other relevant information. A CAA Template for the CAA Form 20b is available for organisations to use.
Light aircraft' means the following non-complex motor-powered aircraft not listed in the air operator certificate of an air carrier licensed in accordance with UK Regulation (EC) No 1008/2008:
- aeroplanes of 2,730 kg maximum take-off mass (MTOM) or less
- rotorcraft of 1,200 kg MTOM or less, certified for a maximum of up to 4 occupants
- other ELA2 aircraft (for example, sailplanes, balloons, small airships)