Introduction to the UK Civil Aviation Authority

This article summarises content delivered by the UK Civil Aviation Authority (CAA) for the ‘Intro to the CAA’ clinic delivered in partnership with the ATI Hub in February 2023. It presents key information about the CAA and provides a simple overview of how aerospace innovators can work with the CAA. 

To register for upcoming clinics and workshops, please visit ATI Hub events.

Who is the UK CAA? 

The UK CAA is the national authority which oversees and regulates civil aviation in the UK. 

As the UK’s aviation regulator, the CAA is responsible for ensuring that: 

  • The aviation industry meets the highest safety standards. 
  • Consumers have choice, value for money, and are protected and treated fairly when they fly. 
  • The aviation industry manages security risks effectively.

The CAA has four key departments that have an interest in regulation of new and innovative technology

Where does the CAA sit in the wider regulatory landscape?

To ensure consistent levels of safety and consumer protection, most aviation regulation and policy is standardised across the world.

Worldwide safety regulations are set by the International Civil Aviation Organisation (ICAO). Whilst the ICAO provides the fundamental guidelines, countries are free to contribute their own requirements, although, amendments must be granted ICAO approval.

Every country has a national aviation authority. These agencies govern and regulate civil aviation, including certifying aircraft airworthiness, licensing pilots and air traffic controllers, licensing airports and enforcing regulations.

The European Aviation Safety Agency (EASA) is responsible for civil aviation safety across the European Union. EASA carries out certification, regulation, and standardisation, and monitors the implementation of standards through inspections in Member States. As a result of Brexit, on 31st December 2020, the UK left EASA and was no longer bound by EU aviation rules. From this date, the CAA was proclaimed the national aviation authority in the UK.

The Federal Aviation Administration (FAA) is the national aviation authority in the US and is responsible for regulating all aspects of civil aviation in North America. The FAA issues and enforces regulations and minimum standards covering manufacturing, operating, and maintaining aircraft.

How do you engage with the CAA?

Here are two key pathways for working with the CAA: pre-application and applying for regulatory approval.

1. You need some advice pre-application.

Why engage?

  • You want to understand which regulations apply to your innovation.
  • You want to find out how to obtain the regulatory approvals you need.
  • You want to learn more about how to engage with the CAA and who to contact.

Who is eligible?

  • You are developing an innovative solution for which adequate regulatory framework is not yet existing or is not mature.
  • You need guidance and advice to prepare your regulatory application.

Pre-application advisory services

The CAA Innovation Hub provides advisory services to aerospace innovators before starting an application for regulatory approval.

The Innovation Hub sits separately from the regulatory approval functions of the CAA. Advisory services are delivered in accordance with the CAA’s Innovation Principles and do not predispose regulatory approvals.
For guidance on your project and to find out how the CAA can help you, please email the Innovation Hub at

The Innovation Hub runs two pre-application advisory services which may be of interest to you.

A. The Gateway Service
The CAA Gateway Service is the first point of call if you are new to the CAA and support to help you understand how to obtain the regulatory approvals you need for your project.

Who is it for?

The Gateway service is for aerospace innovations who:

  • Do not understand which regulations apply to their regulation.
  • Do not understand how to obtain the regulatory approvals they need.
  • Do not know who to contact within the CAA or how to engage with the CAA.

What does the support look like?

The CAA Innovation Hub will set up a meeting to learn more about your innovation, discuss the goals, objectives and timescales associated with your project, as well as answer your questions on regulations.

B. Regulatory Sandbox Service

The CAA Regulatory Sandbox Service offers guidance and advice to help prepare you for your regulatory applications.

Who is it for?

The Regulatory Sandbox Service is the option for you if you are developing an innovative solution for which adequate regulatory framework is either not existing or not yet mature.

What does the support look like?

The CAA Innovation Hub will work with you to:

  • Clarify UK regulations and CAA policies applicable to your innovation.
  • Clarify where UK regulations and CAA policies are not adequate or not mature for your innovation.
  • Identify the safety hazards and define the safety risks for your innovation.
  • Propose a safety argument that mitigates the safety risks.
  • Validate the safety argument through tests and simulations.

2. You are applying for regulatory approval.

Why engage?

  • You are designing and/or producing an aircraft, engine, propellor or Auxiliary Power Unit which needs specific approvals from the CAA.
  • Design Organisation Approval.
  • Production Organisation Approval.
  • Certificate of Airworthiness.
  • Permit to Fly or Experimental Flying.

Who is eligible?

  • You already understand the regulatory framework.
  • You have already prepared your regulatory application.

Submitting an application for regulatory approval

Once you have understood the relevant regulatory frameworks, and prepped your application, you are ready to apply for regulatory approval. Broadly, there are four key types of approval:

A. Design Organisation Approval (DOA)

DOAs are required for applicants wishing to design and seek approval for ‘Part 21’ products (aircraft, engine, propeller) or modifications/repairs to those products. It is also required for applicants for UKTSO Authorisation of Auxiliary Power Units.

B. Production Organisation Approval (POA)

POAs are required for applicants wishing to build for scaled production of Part 21 aircraft, products, parts, and appliances.

C. Certificate of Airworthiness (CoA)

Aircraft that meet the applicable type design standard and are in a condition for safe operation are eligible for the issue of CoAs.

  • Type certificate is the process of establishing that the generic type design meets applicable design and safety requirements.
  • CoA is the process recognising that an individual aircraft meets its relevant Type Design. This is issued for a specific, and for each, aircraft.

D. Temporary Approvals

Where the certification of a particular aircraft is not the goal, for example a prototype not intended for commercial use, alternative temporary approvals are possible.The CAA can give approval required to enable test flights for aircraft without a Type Certificate under the following:

  • Permits to Fly (Permits to fly)
  • Experimental Flying (eConditions)

Hints and tips

  • Always engage early!
  • Provide the CAA with a detailed written description of your project.
  • Understand the CAA Scheme of Charges to estimate costs.
  • For novel technologies, attend and support industry and government level committees and working groups such as ATI, EUROCAE, Jet Zero Council etc.
  • For DOA applicants, be aware of application costs and timelines (>18 months) and attend basis airworthiness training such as Part 21 Subpart J, Accountable Manager etc. Consider using consultancies for advice.

Useful links