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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.

Letters to Owners and Operators (LTOs) were issued by the CAA to owners and operators of aircraft on the UK register.

They generally contain information relating to a variety of technical issues, for example, reminders of forthcoming requirements or clarification of the interpretation of Airworthiness Directives.

LTOs are not mandatory in themselves; however, they may contain significant airworthiness information received from a foreign Aviation Authority or refer to a rule or regulation that is mandatory. The following are still current, however we no longer issue LTOs, we now issue Safety Notices.