EASA Form 1 After Brexit: What UK Organisations Need to Know

Brexit changed the regulatory basis on which UK maintenance organisations release aircraft components. Before the UK left the European Union, UK Part 145 organisations could issue an EASA Form 1, which was generally accepted throughout the EASA system.

That position no longer applies. UK organisations must distinguish between a UK CAA Part 145 approval and a CAA Form 1, and between an EASA Part 145 approval and an EASA Form 1.

The form itself has changed very little. The significant difference is the regulatory approval under which it is issued.

UK Part 145 organisations issue a CAA Form 1

A UK-based maintenance organisation requires UK CAA Part 145 approval to issue a CAA Form 1 for an eligible component. Organisations should check the latest UK CAA guidance for maintenance organisations when establishing the approval and procedural requirements that apply to their activities.

The CAA Form 1 certifies that the component has been manufactured, maintained or inspected in accordance with the applicable UK requirements and the organisation's approved scope of work. Its layout is almost identical to the former EASA Form 1. In practical terms, the most visible difference is the authority block at the top of the document.

However, a CAA Form 1 is not automatically equivalent to an EASA Form 1 for every European regulatory purpose. The receiving operator, owner or maintenance organisation must establish whether the component and its release document are acceptable under the applicable approval and aircraft registration requirements.

The form cannot be considered separately from the approval under which it was issued. For broader background on the regulatory framework, see our guide to CAA legislation, including Part 145 and Part 147.

Releasing components to EU-registered aircraft

If a UK organisation also wants to release components into the EASA system for use on EU-registered aircraft, a UK CAA Part 145 approval alone is generally insufficient.

The organisation will normally need a separate EASA Part 145 approval as a third-country maintenance organisation. EASA provides specific information on third-country maintenance organisations and their regulatory approval arrangements.

This creates a dual-approval structure:

• UK CAA Part 145 approval for work released with a CAA Form 1.
• EASA Part 145 approval for work released with an EASA Form 1.

For a UK MRO, this can mean:

• two regulatory audits;
• two sets of application and approval fees;
• separate continuing compliance obligations;
• two regulatory manuals, or clearly segregated procedures within one manual;
• separate findings and corrective action processes; and
• two sets of ongoing surveillance activity.

The organisation must also ensure that its approval scope, facilities, tooling, data, personnel authorisations and quality or compliance arrangements support both regulatory frameworks.

These requirements should be read alongside the current EASA continuing airworthiness rules, as applicable to the organisation's approval and release activities.

The same engineer may need to identify the approval route first

Dual approval creates an important operational issue. The same certifying staff member may perform the same maintenance task on the same component, but the release route may differ.

Before issuing the certificate, the engineer and the organisation must establish:

• which authority's approval covers the work;
• which customer or aircraft registration requirement applies;
• which approved maintenance data is being used;
• whether the component is being released under the UK or EASA approval;
• whether the engineer is authorised under that specific organisation approval; and
• which Form 1 must be completed and issued.

A certifying engineer does not choose between a CAA Form 1 and an EASA Form 1 simply because the documents look similar. The choice follows the organisation's approval, the work package and the intended regulatory destination of the component.

The organisation should build this decision into its work order, planning and certification procedures. Relying on informal knowledge or individual judgement creates a risk of issuing the correct-looking document under the wrong approval basis.

Where the work involves an independent inspection or duplicate inspection, personnel should also understand the applicable competence, authorisation and independence requirements. Our guide explains who can perform an independent inspection in aircraft maintenance.

The Form 1 is not the approval

A Form 1 is a release certificate. It is not, by itself, evidence that the issuing organisation is approved by every authority whose system may later receive the component.

The receiving party may need to verify:

• the issuing organisation's Part 145 approval;
• the organisation's approval scope;
• the validity of the approval on the date of release;
• the identity and authorisation of the certifying staff;
• the component's part number, serial number and status;
• the applicable maintenance or inspection data; and
• the acceptance provisions applying to the destination aircraft or operator.

This is particularly important where a component is transferred between UK, EU and other international regulatory systems. Acceptance depends on the relevant bilateral arrangements, third-country rules and operator requirements, not merely on the title printed on the certificate.

What changed for US and other third-country organisations?

US and other third-country MROs experienced a particularly visible change.

Before Brexit, the EU-US aviation safety arrangements allowed appropriately approved FAA repair stations to issue EASA Form 1 documentation in circumstances covered by the applicable agreement. The UK also accepted that arrangement while it was part of the EU regulatory framework.

That position changed on 1 January 2025. From that date, US repair stations releasing parts into the UK system require UK CAA Part 145 approval and must issue a CAA Form 1 for the relevant UK release route. Organisations should verify the current position against the applicable UK-EU and international arrangements rather than relying on historic acceptance practices.

The FAA Part 145 repair station framework remains relevant to US operators and repair stations, but it is a US regulatory system and should not be treated as the default route for UK or EASA acceptance. An FAA approval, an EASA approval and a UK CAA approval are separate regulatory permissions.

More than 700 US repair stations reportedly applied for UK approval. Organisations that did not obtain the necessary approval can no longer legally release parts into the UK system on the basis of their previous EASA arrangements.

Internal controls UK organisations should review

UK organisations holding, or planning to hold, both UK and EASA Part 145 approvals should review the following areas.

Work order identification

Work orders should identify the intended release authority before maintenance begins. The organisation should not wait until certification to decide whether the component requires a CAA Form 1 or an EASA Form 1.

Scope and capability

The organisation must confirm that the relevant approval covers:

• the component category;
• the applicable rating;
• the maintenance capability;
• the facility and location;
• the approved data; and
• the intended release document.

For component organisations, this is particularly important where different workstations or specialist processes sit under different approval scopes.

Certifying staff authorisations

Certifying staff must be authorised by the relevant organisation under the applicable Part 145 procedures. Technical experience or a personal aircraft maintenance licence does not, by itself, grant authority to issue either form.

Authorisations should clearly reflect the organisation, approval route, component scope and certification privileges involved. Engineers should also keep accurate evidence of relevant experience and competence. AeroTech Careers explains how to fill out a CAP 741 logbook and how to avoid common CAP 741 logbook mistakes.

Maintain clearer Part 66 records with Part 66 Logbook Analysis. Analyse your logbook today and identify gaps before they affect your licensing or competence evidence.

Manuals and procedures

The exposition or maintenance organisation procedures manual should explain how the organisation:

• separates UK and EASA work;
• controls the use of approved data;
• identifies the applicable release certificate;
• manages subcontracted and contracted work;
• handles component transfers between approval systems;
• controls stamps, signatures and electronic certification; and
• prevents an incorrect form from being issued.

For help understanding the documents used during maintenance planning and certification, see our explanation of AMM, IPC, SRM and wiring diagrams.

Where one manual supports both approvals, the interfaces must be explicit. Broad statements that the organisation complies with both systems are insufficient.

Training and recurrent competence

Certifying and support staff need more than awareness of the visual difference between the two forms. They must understand the regulatory conditions that determine when each document may be issued.

Organisations with UK CAA and EASA Part 145 approvals must manage recurrent training and competence in accordance with the applicable requirements. Under Part 145 arrangements, certifying and support staff are required to receive recurrent training within a two-year period. Training should address practical changes affecting the organisation, including:

• approval boundaries;
• release certification;
• authority-specific procedures;
• changes to acceptance requirements; and
• lessons identified through audits, findings and operational events.

A short briefing on the form layout is unlikely to be sufficient where staff work across two approval systems. Organisations developing internal capability can also review available Part 147 training schools.

Common compliance mistakes

Treating the CAA Form 1 as an EASA Form 1

The near-identical layout can lead staff or customers to assume that the documents are interchangeable. They are not interchangeable simply because their fields and appearance are similar.

Issuing the form under the wrong approval

A component may have been maintained correctly, but the certificate can still be unacceptable if it was issued under an approval that does not support the intended destination.

Assuming customer location determines the release route

The customer's location is not always decisive. The organisation must consider the aircraft registration, operator requirements, destination regulatory system and applicable approval arrangements.

Using an EASA procedure for a UK release

A UK organisation with both approvals must ensure that the work is controlled under the correct approved procedures. Staff should not use an EASA release process for a component being released solely under the UK approval, or vice versa.

Failing to control subcontracted work

Subcontractors must be approved, contracted and controlled under the appropriate regulatory arrangements. A subcontractor's certificate cannot automatically be accepted merely because the subcontractor is familiar or has been used previously.

A practical decision process

Before releasing a component, a UK organisation should be able to answer five questions:

1. Where will the component be used or accepted?
2. Which authority's approval covers the release?
3. Does the organisation hold the required approval and scope?
4. Is the certifying staff member authorised under that approval?
5. Which release certificate is required, a CAA Form 1 or an EASA Form 1?

If any answer is unclear, the component should not be released until the organisation's quality, compliance or airworthiness function has resolved the issue.

What UK organisations should do now

UK MROs should treat Form 1 control as an approval management issue, not a document format issue. Practical actions include:

• mapping customers and aircraft registrations against the required release route;
• confirming whether an EASA Part 145 third-country approval is commercially necessary;
• reviewing UK CAA and EASA approval scopes;
• separating work orders and certification records by approval basis;
• auditing certifying staff authorisations;
• updating manuals and electronic maintenance systems;
• verifying subcontractor and supplier acceptance routes;
• providing authority-specific recurrent training; and
• checking that commercial teams do not promise EASA release where the organisation holds only UK approval.

Organisations should also monitor current regulatory publications directly from the UK Civil Aviation Authority and EASA, particularly when approval arrangements or bilateral agreements change.

The post-Brexit position

The post-Brexit environment has not made component certification impossible, but it has removed the assumption that one UK approval automatically provides access to the entire EASA system.

For UK organisations, the distinction is straightforward:

• UK CAA Part 145 approval supports the issue of a CAA Form 1.
• EASA Part 145 approval supports the issue of an EASA Form 1.
• A UK organisation seeking access to both markets may need both approvals.

The physical form is familiar, but the regulatory basis is different. UK MROs that understand and control that distinction will be better placed to avoid rejected components, delayed deliveries, audit findings and unauthorised releases.

For further aviation maintenance guidance, visit the AeroTech Careers Blog.