If no deal is agreed between the EU and the UK, organisations (Part 21 Subpart O) which require approvals for equipment to be installed on aircraft might need to take action to maximise continuity and stability for the aviation sector. The actions required would depend on individual circumstances and are a matter for each business and individual to consider. This page sets what you need to consider to prepare for such an eventuality.

Technical Standard Order (Part 21 Subpart O)

Would the CAA duplicate the existing Technical Standard Order/European Technical Standard Order systems in the UK after the UK has left the EU?

Except in the case where appropriate TSO/ETSO standards do not already exist, the CAA does not intend to generate equipment specification requirements separate to ETSO and TSO for a two-year time-limited period. We will adopt the standards currently in CS-ETSO for any applications during that time.


My organisation holds Alternative Procedures to Design Organisations (ADOA) under Subpart O from EASA and issues data to UK Production Organisations (POA) for manufacture and release. Do I need to apply for a UK AP to DOA to continue to do this after EU exit in a no-deal scenario?

Not at the moment. EASA ADOA data (including minor changes under Subpart O) would be accepted for manufacture under a UK POA for the two-year time-limited period, and permanently after that date provided that the design data has not changed.

If at the end of the two-year time limited period there is no agreement for continued acceptance of EASA approvals, and there was a need to make such a design change, existing ADOA organisations would need to make an application to the CAA to continue to manufacture under a UK POA.

ADOA organisations wishing to make major changes or to make new applications for equipment approval during the two-year time limited period would need to seek UK ADOA approval to manufacture under a UK POA.

The CAA’s Scheme of Charges sets out the fees required by those organisations planning to make an application to the CAA for ADOA after the date of EU exit.


If my ADOA continues to be accepted, what is the effect of the UK’s exit from the EU on my current ETSO arrangements?

In the event that the UK leaves the EU without an agreement, UK POAs would no longer be able to release your equipment/appliances using an EASA Form 1. From that date, the POA would have to make releases via a CAA Form 1. Please refer to the dedicated Aerospace Production Organisation section of the microsite for further details of the options available for production organisations.


How could my organisation make major changes requiring a new Part Number or make an application for new equipment approvals after the date the UK leaves the EU?

Your organisation would need to make an application to the CAA for ADOA to support a release under a UK Part 21G. Note that if the appliance is also going to be released under an approval issued by EASA, a corresponding change would also need to be approved in the EASA system.