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.

The purpose of this Supplementary Instruction (SI) to the Radiotelephony Manual (CAP 413) is to detail changes to callsign suffixes used in Police, Helicopter Emergency Medical Services (HEMS), and Search And Rescue (SAR) activities as well as the associated procedures detailed within the manual. In addition, this SI also introduces changes to callsigns used in SAR activities.
Review comment:
Version date:
View file:

This publication features in the following categories.

This publication features in the following series.