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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.



The approval of engines in accordance with Part 21 is ratified by the issue of a Type Certificate (TC) or Restricted TC (RTC) by the CAA.

In general, there will be a Type Certificate Data Sheet (TCDS) associated with each TC or RTC issued.

The TCDS records the basis of certification, the designation of each approved variant and general information concerning the design.

The UK left the European Union aviation system on 31 December 2020, and as such is no longer part of European Union aviation institutions, including the European Union Aviation Safety Agency (EASA).

TCDSs valid up to this date are considered approved by the CAA and have been published as they were released by EASA, including their identification number.

Going forward, some TCDSs will continue to refer to EU law and carry the EASA logo until they are required to be amended. Where references to EU law are made, they now relate to those laws as retained (and amended in UK domestic law) under the European Union (Withdrawal) Act 2018.

Once amended, a TCDS will have a new identification number to make readily intelligible the difference and will be published on this page.