Supplementary Instruction
CAP 413
Safety and Airspace Regulation Group
Airspace, ATM & Aerodromes
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Number: 2023/01 Issued: 7 July 2023
Issue: 1 Effective: 7 September 2023
Police, HEMS and SAR Callsigns
1 Introduction
1.1 The purpose of this Supplementary Instruction (SI) is to detail changes being made to the to the
Radiotelephony Manual (CAP 413) relating to callsign suffixes used in Police, Helicopter
Emergency Medical Services (HEMS), and Search And Rescue (SAR) activities and the
associated procedures detailed within the manual. In addition, this SI also introduces changes
to callsigns used in SAR activities.
2 Background
2.1 Following the CAA’s review of callsigns and suffixes used in Police, HEMS and SAR operations
an airspace policy statement has been published to regulate their use and to introduce
improvements.
2.2 This airspace policy statement introduces the following changes to CAP 413:
1 Police and HEMS aircraft engaged in training will suffix their callsign with the word “Zulu”
to alert ATS units of the corresponding flight priority.
2 Aircraft operators involved in SAR activities will now use the callsign:
a. “BRITISH RESCUE” when the safety of life is involved, including HEMS emergency
operational tasks or humanitarian tasks. The callsign “BRITISH RESCUE” may be
abbreviated to “RESCUE” by an ATS unit after initial contact when appropriate within
the UK FIR.
b. “COASTGUARD” when engaged in other tasks, including SAR or HEMS positioning
flights, and training flights.
2.3 For further information please review the airspace policy statement, which can be downloaded
from the CAA’s website using the following hyperlink:
Policy for the management of Police, Helicopter Emergency Medical Services and Search And
Rescue flight callsigns (Published: 7 July 2023).
3 Amendment to CAP 413
3.1 With effect from 7 September 2023, CAP 413 is amended as shown at Annex A to this SI.
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3.2 This change will be incorporated into CAP 413 with the next publication.
4 Queries
4.1 Any queries or further guidance required on the content of this SI should be marked for the
attention of Airspace & ATM Policy and sent to [email protected]o.uk
4.2 Any queries relating to the availability of this SI should be marked for the attention of Safety &
Business Delivery and sent to ats.documents@caa.co.uk
5 Cancellation
5.1 This SI shall remain in force until incorporated into CAP 413 or is cancelled, suspended or
amended.
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Annex A
Chapter 2: Radiotelephony
Police Flights
2.31 A Police flight is defined as a flight by an aircraft operating under a Police Air Operator’s
Certificate, the purpose of which is to facilitate police operations, which includes the following:
1. Responding to a ‘Police Emergency’. The pilot of a police aircraft is likely to declare a
“Police Emergency” in situations where an immediate response is required when life is at
immediate risk, or a serious crime or major incident is in progress.
2. Supporting ground personnel in often sensitive and serious operations.
3. Non-standard and other flights.
The callsign for a Police flight consists of three elements:
1. The radiotelephony callsign “POLICE”.
2. A two, or exceptionally three-digit individual aircraft identifier.
3. The two, or three-digit aircraft identifier may be suffixed with a flight category to indicate
the priority required by the pilot. Suffix “Alpha” indicates a ‘Police Emergency’ is in
progress, e.g., “POLICE 01 Alpha”. The absence of a suffix indicates the flight is to be
handled as flight category ‘B’. Suffix “Zulu” indicates flight training, testing or other flights
involving Police aircraft, e.g., “POLICE 01 Zulu”.
The flight categories relevant to Police flying operations are:
1. Flight Category A: authorised for use by aircraft which have declared a “Police
Emergency”.
2. Flight Category B: normal operational priority.
3. Flight Category Z: used for training, test and other flights involving Police aircraft.
Helicopter Emergency Medical Service Flights
2.32 A HEMS flight is a flight by a helicopter operating under a HEMS approval, the purpose of
which is to facilitate emergency medical assistance, where immediate and rapid transportation
is essential.
The callsign for a HEMS flight consists of three elements:
1. The radiotelephony callsign “HELIMED”.
2. A two-digit individual aircraft identifier allocated to each HEMS aircraft by CAA.
3. The two-digit individual aircraft identifier may be suffixed with the flight category to
indicate the priority required by the pilot. Suffix “Alpha”, “Echo”, or “Zulu” indicates the
corresponding flight category. The absence of a suffix indicates the ‘normal flight’
category, e.g. “HELIMED 01”.
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The flight categories relevant to HEMS operations are:
1. Flight Category A – applies to all HEMS flights, as defined at above paragraph.
2. Flight Category E - is authorised for use by an aircraft positioning for the purpose of
conducting HEMS duties, e.g., returning to base after delivering a casualty to hospital. It
is afforded priority over normal flights.
3. Flight Category Z - used for training flights.
Search And Rescue
2.33 SAR flights operate to and from incidents where a response is required for the safety of life,
which might be time critical and may also involve the transportation of casualties to hospital.
The callsign for SAR flights consists of the following elements:
1. The radiotelephony callsign is task dependent and will be “COASTGUARD” or “BRITISH
RESCUE”. “COASTGUARD” callsigns can be re-tasked by the JRCC and such flights
will adopt the “BRITISH RESCUE” callsign. In addition, SAR helicopters may on
occasions be required to undertake HEMS tasks and will also use the “BRITISH
RESCUE” callsign. The callsign “BRITISH RESCUE” may be abbreviated to “RESCUE”,
by an Air Traffic Services Unit within the UK FIR when appropriate after initial contact.
2. A three-digit individual aircraft callsign allocated to each SAR Base and aircraft by the
Joint Rescue Coordination Centre (JRCC).
3. The three-digit individual aircraft identifier may be suffixed with the flight category to
indicate the priority required by the pilot. Suffix “Alpha”, “Bravo”, “Echo”, or “Zulu”
indicates the corresponding flight category. The absence of a suffix indicates the ‘normal
flight’ category.
The flight categories relevant to SAR operations are:
1. Flight Category A: applies to SAR flights when the safety of life is involved, including
HEMS tasks. Callsign “BRITISH RESCUE [XXX] Alpha”
2. Flight Category B: applies to SAR or humanitarian flights when priority is required,
including HEMS tasks. Callsign “BRITISH RESCUE [XXX] Bravo”
3. Flight Category E: is authorised for use by SAR aircraft carrying out a positioning flight
following a SAR or HEMS task, e.g., returning to its base after delivering a
patient/casualty. Callsign “COASTGUARD [XXX] Echo”
4. Normal Flight Category: applies to SAR aircraft in circumstance when additional priority
is not required. Callsign “COASTGUARD [XXX]”
5. Flight Category Z: used for training and testing flights in SAR aircraft. Callsign
“COASTGUARD [XXX] Zulu”
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Student Flights
2.34 On initial contact with an ATSU, student pilots who are flying solo shall use the callsign prefix
‘STUDENT’. Once acknowledged, it will not normally be necessary for student pilots to use the
prefix in subsequent transmissions unless they feel they are being instructed to do something
with which they are unfamiliar. Controllers will acknowledge the initial call, again using the
prefix, and can be expected, as far as practicable, to make due allowance for the limited
experience and ability of student pilots in determining the pace and complexity of instructions
and/or information which are subsequently passed.
