March 27, 2023


Sofema Aviation Services (SAS) looks at the regulatory drivers for the issue of Airworthiness Directives (ADs) by the United Kingdom Civil Aviation Authority (UK CAA)

Introduction to Airworthiness Directives

Airworthiness Directives are issued to address unsafe conditions.

Aircraft on the UK Register are required to comply with all applicable Airworthiness Directives.

As a result of the UK leaving the EU, and because the CAA is no longer a member of EASA, the process of identifying the ADs that are applicable to your product has changed.

Check out the following document

Mandatory Requirements for Airworthiness CAP 747

Section 1, Part 1 provides flowcharts to assist in identifying the applicable ADs and other mandatory requirements for airworthiness relating to your product. For ADs issued for a product, part or appliance from 01/01/2021.

Action Required When There is a Potential Need to Report – You should contact the National Aviation Authority of the State of Design.

  • Note: Prior to July 2003, UK ADs for UK Products were a number only linked to a CAA-declared Mandatory Service Bulletin (SB) issued by the Type Certificate Holder.
  • If you have the SB you have the AD. These AD and SB Numbers are listed in CAP 476, which is currently in the final issue (September 2004) and no longer amended.

o Those Service Bulletins remain mandatory unless cancelled and/or superseded by a new AD.

Note: Mandatory Requirements issued by the CAA for non-Part 21 products of UK Design or CAA ADs for Part 21 products issued under Article 70 of UK Regulation (EU) No. 2018/1139 are available for download from the website before they are published in CAA publication CAP 747.

Current Position regarding CAP 747

  • Before 1 January 2021, these Mandatory Requirements were removed from the website after they were incorporated in CAP 747.
  • However, in order to provide a single place where all ADs issued by the CAA since 1 January 2021 can be found, these ADs will now remain available on the website after they have been incorporated in CAP 747.

A list of United Kingdom Civil Aviation Authority Airworthiness Directives – UK CAA AD’s is available here

Concerning State of Design ADs not Adopted by the CAA (from 1 January 2021)

Note: From 1 January 2021, CAP 747 now also includes (in Section 2 Part 2), State of Design Airworthiness Directives not Adopted by the CAA. These ADs are listed on the CAA website:

See document here 

Alternate Method of Compliance to an Airworthiness Directive (AMOC)

Please see the following link to view the document

Next Steps

Follow this link to our Library to find & Download related documents for Free.

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