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UK Civil Aviation Regulations

These are published by the CAA on our UK Regulations pages. EU Regulations and EASA Access Guides published by EASA no longer apply in the UK. Our website and publications are being reviewed to update all references. Any references to EU law and EASA Access guides should be disregarded and where applicable the equivalent UK versions referred to instead.



In 2014 the Civil Aviation Authority (CAA), in response to events, carried out a review of Offshore Helicopter Operations. The review was published in Safety review of offshore public transport helicopter operations in support of the exploitation of oil and gas (CAP1145) considering Passenger Safety and Survivability, Operations, Research and Airworthiness.

The airworthiness aspects, of the review, made several actions and recommendations to the CAA and external stakeholders. One of those actions, known as A31, said the CAA would establish an Offshore Maintenance Standards Improvement Team with Offshore helicopter operators. The objective of this group was to achieve a step change in maintenance standards.

After an initial meeting with offshore operators and wider industry, the CAA agreed to expand the Maintenance Standards Improvement Team concept to all sectors of aviation.

Since 2014 the CAA has worked with industry to establish several working groups, with over 50 organisations representing the UK aviation industry.

To reflect the broad approach being taken to cover all aspects of Airworthiness, in 2020 the name was changed from Maintenance Standards Improvement Team (MSIT) to Airworthiness Standards Improvement Team (AWSIT).

Working groups are now established in the following areas:

  • Part-145
  • Part-M/CAMO
  • Part-66/147
  • Part-21G
  • Rotorcraft

The Maintenance / Airworthiness Standards Improvement initiative represented an important change, with the CAA and Industry working in collaboration to improve safety, specifically the ability to perform maintenance, manage continued airworthiness, manage production and train engineers to the highest standards.

The support of industry in developing the work of the AWSIT has been crucial. Each organisation and its representatives contribute their time and effort for the benefit of improving standards and enhancing safety.

Through this collaborative approach we have shared knowledge of industry strengths and weaknesses, along with the challenges and opportunities to improve. The groups continue to work towards delivering outputs for the benefit of industry which includes further guidance: