We use necessary cookies to make our website work. We'd also like to use optional cookies to understand how you use it, and to help us improve it.

For more information, please read our cookie policy.

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.

Air Traffic Controllers can report an Alleged Breach of Air Navigation Legislation (ABANL) by completing the CA 939 form.

Examples of when a report may be required include, but are not limited to:

  • infringement of controlled airspace
  • low flying
  • failure to comply with ATC instructions

Please email the completed CA939 form to iet@caa.co.uk or return it by post to address shown on the form.

Please note that the CA939 form is only for use by Air Traffic Controllers

Guidance for members of the public on how to report a potential breach of aviation law

Making a report

Please ensure that the event is described with as much detail as possible.

Reports should include the following information where appropriate:

  • the identification of all aircraft involved together with relative tracks and times
  • any loss of separation associated with the ABANL
  • a statement as to the degree of actual impact the event had on ATC operations including any tactical avoiding or delaying action taken by ATC

Detailed guidance for Air Traffic Controllers wishing to report an ABANL is available in Section 6 of CAP 493.