CAP 413 User Manual

Safety Regulation Group

CAP 413

Radiotelephony Manual

Edition 20

www.caa.co.uk

Safety Regulation Group

CAP 413

Radiotelephony Manual

Edition 20

17 November 2011

CAP 413 Radiotelephony Manual

© Civil Aviation Authority 2011

All rights reserved. Copies of this publication may be reproduced for personal use, or for use within a
company or organisation, but may not otherwise be reproduced for publication.

To use or reference CAA publications for any other purpose, for example within training material for
students, please contact the CAA at the address below for formal agreement.

ISBN 978 0 11792 610 3

First published September 1978
Second edition April 1984
Third edition August 1992
Fourth edition January 1994
Fifth edition January 1995
Sixth edition January 1996
Seventh edition December 1996
Eighth edition January 1998
Ninth edition January 1999
Tenth edition January 2000
Eleventh edition January 2001
Twelfth edition 5 February 2002 (corrected 7 February 2002)
Thirteenth edition 1 October 2002
Fourteenth edition 1 September 2003
Fifteenth edition 1 September 2004
Sixteenth edition 1 May 2006
Seventeenth edition 21 July 2008
Eighteenth edition 19 February 2009 (effective date 12 March 2009)
Nineteenth edition 15 December 2009
Twentieth edition 31 March 2011
Twentieth edition incorporating amendments to 17 November 2011

Enquiries regarding the content of this publication should be addressed to:
Aerodrome and Air Traffic Standards Division, Safety Regulation Group, Civil Aviation Authority, Aviation
House, Gatwick Airport South, West Sussex, RH6 0YR

The latest version of this document is available in electronic format at www.caa.co.uk/publications,
where you may also register for e-mail notification of amendments.

Published by TSO (The Stationery Office) on behalf of the UK Civil Aviation Authority.

Printed copy available from:

TSO, PO Box 29, Norwich NR3 1GN www.tsoshop.co.uk
Telephone orders/General enquiries: 0844 477 7300 E-mail: [e-mail]
Fax orders: 0870 600 5533 Textphone: 0870 240 3701

CAP 413 Radiotelephony Manual

Amendment Record

Amendment
Number

1 17 November 2011 CAA 17 November 2011

Amendment Date Incorporated by Incorporated on

CAP 413 Radiotelephony Manual

Amendment
Number

Amendment Date Incorporated by Incorporated on

CAP 413 Radiotelephony Manual

List of Effective Pages

Chapter Page Date Chapter Page Date

iii 17 November 2011
iv 17 November 2011
v 17 November 2011
Contents 1 17 November 2011
Contents 2 17 November 2011
Contents 3 17 November 2011
Contents 4 17 November 2011
Contents 5 17 November 2011
Contents 6 17 November 2011
Contents 7 17 November 2011
Explanatory Note 1 17 November 2011
Revision History 1 17 November 2011
Revision History 2 17 November 2011
Foreword 1 31 March 2011
Foreword 2 31 March 2011
Chapter 1 1 17 November 2011
Chapter 1 2 17 November 2011
Chapter 1 3 17 November 2011
Chapter 1 4 31 March 2011
Chapter 1 5 31 March 2011
Chapter 1 6 31 March 2011
Chapter 1 7 17 November 2011
Chapter 1 8 17 November 2011
Chapter 1 9 17 November 2011
Chapter 1 10 17 November 2011
Chapter 2 1 31 March 2011
Chapter 2 2 31 March 2011
Chapter 2 3 31 March 2011
Chapter 2 4 31 March 2011
Chapter 2 5 31 March 2011
Chapter 2 6 31 March 2011
Chapter 2 7 31 March 2011
Chapter 2 8 31 March 2011
Chapter 2 9 31 March 2011
Chapter 2 10 31 March 2011
Chapter 2 11 31 March 2011
Chapter 2 12 31 March 2011
Chapter 2 13 31 March 2011
Chapter 2 14 17 November 2011
Chapter 2 15 17 November 2011
Chapter 2 16 31 March 2011
Chapter 2 17 31 March 2011
Chapter 2 18 31 March 2011
Chapter 2 19 31 March 2011

Chapter 2 20 31 March 2011
Chapter 2 21 31 March 2011
Chapter 2 22 31 March 2011
Chapter 3 1 17 November 2011
Chapter 3 2 17 November 2011
Chapter 3 3 31 March 2011
Chapter 3 4 31 March 2011
Chapter 3 5 31 March 2011
Chapter 3 6 31 March 2011
Chapter 3 7 31 March 2011
Chapter 3 8 31 March 2011
Chapter 3 9 31 March 2011
Chapter 3 10 31 March 2011
Chapter 3 11 31 March 2011
Chapter 4 1 31 March 2011
Chapter 4 2 17 November 2011
Chapter 4 3 17 November 2011
Chapter 4 4 31 March 2011
Chapter 4 5 31 March 2011
Chapter 4 6 31 March 2011
Chapter 4 7 31 March 2011
Chapter 4 8 31 March 2011
Chapter 4 9 31 March 2011
Chapter 4 10 31 March 2011
Chapter 4 11 31 March 2011
Chapter 4 12 17 November 2011
Chapter 4 13 17 November 2011
Chapter 4 14 17 November 2011
Chapter 4 15 17 November 2011
Chapter 4 16 17 November 2011
Chapter 4 17 17 November 2011
Chapter 4 18 31 March 2011
Chapter 4 19 17 November 2011
Chapter 4 20 17 November 2011
Chapter 4 21 17 November 2011
Chapter 4 22 31 March 2011
Chapter 4 23 31 March 2011
Chapter 4 24 31 March 2011
Chapter 4 25 31 March 2011
Chapter 4 26 17 November 2011
Chapter 4 27 31 March 2011
Chapter 4 28 31 March 2011
Chapter 4 29 31 March 2011
Chapter 4 30 31 March 2011

17 November 2011

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CAP 413 Radiotelephony Manual

Chapter Page Date Chapter Page Date

Chapter 4 31 17 November 2011
Chapter 4 32 31 March 2011
Chapter 4 33 17 November 2011
Chapter 4 34 31 March 2011
Chapter 4 35 31 March 2011
Chapter 4 36 17 November 2011
Chapter 4 37 31 March 2011
Chapter 4 38 31 March 2011
Chapter 4 39 31 March 2011
Chapter 4 40 31 March 2011
Chapter 4 41 31 March 2011
Chapter 4 42 31 March 2011
Chapter 4 43 17 November 2011
Chapter 4 44 17 November 2011
Chapter 4 45 17 November 2011
Chapter 4 46 17 November 2011
Chapter 5 1 31 March 2011
Chapter 5 2 31 March 2011
Chapter 5 3 31 March 2011
Chapter 5 4 17 November 2011
Chapter 5 5 17 November 2011
Chapter 5 6 17 November 2011
Chapter 5 7 17 November 2011
Chapter 5 8 17 November 2011
Chapter 5 9 17 November 2011
Chapter 5 10 17 November 2011
Chapter 5 11 17 November 2011
Chapter 6 1 31 March 2011
Chapter 6 2 31 March 2011
Chapter 6 3 31 March 2011
Chapter 6 4 31 March 2011
Chapter 6 5 31 March 2011
Chapter 6 6 31 March 2011
Chapter 6 7 17 November 2011
Chapter 6 8 31 March 2011
Chapter 6 9 31 March 2011
Chapter 6 10 31 March 2011
Chapter 6 11 31 March 2011
Chapter 6 12 31 March 2011
Chapter 6 13 31 March 2011
Chapter 6 14 31 March 2011
Chapter 6 15 31 March 2011
Chapter 6 16 31 March 2011
Chapter 6 17 31 March 2011
Chapter 6 18 31 March 2011
Chapter 6 19 31 March 2011

Chapter 6 20 31 March 2011
Chapter 6 21 31 March 2011
Chapter 6 22 31 March 2011
Chapter 6 23 31 March 2011
Chapter 6 24 17 November 2011
Chapter 6 25 31 March 2011
Chapter 6 26 31 March 2011
Chapter 6 27 31 March 2011
Chapter 6 28 17 November 2011
Chapter 6 29 17 November 2011
Chapter 6 30 17 November 2011
Chapter 7 1 31 March 2011
Chapter 7 2 31 March 2011
Chapter 7 3 31 March 2011
Chapter 7 4 31 March 2011
Chapter 7 5 31 March 2011
Chapter 8 1 31 March 2011
Chapter 8 2 31 March 2011
Chapter 8 3 17 November 2011
Chapter 8 4 17 November 2011
Chapter 8 5 17 November 2011
Chapter 8 6 17 November 2011
Chapter 8 7 17 November 2011
Chapter 9 1 31 March 2011
Chapter 9 2 31 March 2011
Chapter 9 3 31 March 2011
Chapter 9 4 31 March 2011
Chapter 9 5 31 March 2011
Chapter 9 6 31 March 2011
Chapter 9 7 31 March 2011
Chapter 10 1 31 March 2011
Chapter 10 2 31 March 2011
Chapter 10 3 31 March 2011
Chapter 10 4 31 March 2011
Chapter 10 5 31 March 2011
Chapter 10 6 31 March 2011
Chapter 10 7 31 March 2011
Chapter 10 8 31 March 2011
Chapter 10 9 31 March 2011
Chapter 10 10 31 March 2011
Chapter 10 11 31 March 2011
Chapter 10 12 31 March 2011
Chapter 10 13 31 March 2011
Chapter 10 14 17 November 2011
Chapter 10 15 31 March 2011
Chapter 10 16 31 March 2011

17 November 2011

Page iv

CAP 413 Radiotelephony Manual

Chapter Page Date Chapter Page Date

Chapter 10 17 31 March 2011
Chapter 10 18 31 March 2011
Chapter 10 19 31 March 2011
Chapter 10 20 31 March 2011
Chapter 10 21 17 November 2011
Chapter 10 22 31 March 2011
Chapter 10 23 17 November 2011
Chapter 10 24 17 November 2011
Chapter 10 25 31 March 2011
Chapter 10 26 31 March 2011
Chapter 10 27 31 March 2011
Chapter 11 1 31 March 2011
Chapter 11 2 31 March 2011
Chapter 11 3 31 March 2011
Chapter 11 4 31 March 2011
Chapter 11 5 31 March 2011
Chapter 11 6 31 March 2011
Chapter 11 7 31 March 2011
Chapter 11 8 31 March 2011
Chapter 11 9 31 March 2011
Chapter 11 10 31 March 2011
Chapter 11 11 31 March 2011
Chapter 11 12 31 March 2011
Chapter 11 13 31 March 2011
Chapter 11 14 31 March 2011
Chapter 11 15 17 November 2011
Chapter 11 16 31 March 2011
Chapter 11 17 17 November 2011
Chapter 11 18 31 March 2011
Chapter 11 19 17 November 2011
Chapter 11 20 17 November 2011
Chapter 11 21 31 March 2011
Chapter 11 22 17 November 2011
Chapter 11 23 17 November 2011
Chapter 11 24 17 November 2011
Chapter 11 25 31 March 2011
Chapter 11 26 31 March 2011
Chapter 11 27 17 November 2011
Chapter 11 28 17 November 2011
Chapter 11 29 31 March 2011
Chapter 11 30 31 March 2011
Chapter 11 31 31 March 2011
Chapter 11 32 17 November 2011
Chapter 11 33 31 March 2011
Chapter 11 34 31 March 2011
Chapter 11 35 17 November 2011

Chapter 11 36 31 March 2011
Appendix 1 1 31 March 2011
Appendix 1 2 17 November 2011
Appendix 1 3 17 November 2011
Appendix 1 4 17 November 2011
Appendix 1 5 31 March 2011
Appendix 2 1 31 March 2011
Appendix 2 2 31 March 2011
Appendix 2 3 31 March 2011
Appendix 2 4 31 March 2011
Bibliography 1 17 November 2011
Index 1 17 November 2011
Index 2 17 November 2011
Index 3 17 November 2011
Index 4 17 November 2011
Index 5 17 November 2011
Index 6 17 November 2011
Index 7 17 November 2011
Index 8 17 November 2011
Index 9 17 November 2011

17 November 2011

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CAP 413 Radiotelephony Manual

Contents

List of Effective Pages iii

Explanatory Note 1

Revision History 1

Foreword 1

Document Description 1

Document Purpose 1
Document Applicability 1
Document Source 1
Document Format 1
Document Revisions 2
Document Availability 2
Document Comments and Queries 2

Chapter 1 Glossary

Terms 1

Definitions 1
Abbreviations 5

Chapter 2 Radiotelephony

General Procedures 1

Introduction 1
Transmitting Technique 1
Transmission of Letters 2
Transmission of Numbers 3
Transmission of Time 4
Standard Words and Phrases 5
Callsigns for Aeronautical Stations 7
Callsigns for Aircraft 8
Military Aircraft Callsigns 10
Continuation of Communications 11

17 November 2011

Corrections and Repetitions 13
Acknowledgement of Receipt 13
Transfer of Communications 13
Clearance Issue and Read-back Requirements 14
Withholding Clearances 17

Contents Page 1

CAP 413 Radiotelephony Manual

Simultaneous Transmissions 18
Complying with Clearances and Instructions 18
Communication Failure 19
Test Transmissions 20
Pilot Complaints Concerning Aeronautical Telecommunications 21
Air Traffic Service Complaints Concerning Aircraft

Communications 21
Hours of Service and Communications Watch 21
Record of Communications 22
Categories of Message 22

Chapter 3 General Phraseology

General 1

Introduction 1
Level Reporting 1
Speed Control 5
Initial Call – IFR flights 6
Initial Call – VFR Flight 7
Passing Message Details 7
Position Reporting 8
Flight Plans 9
Low Visibility Procedures 10
Delays 10

Chapter 4 Aerodrome Phraseology

Aerodrome Control Service Phraseology 1

Introduction 1
Type of Service 1
Departure Information and Engine Starting Procedures 1
Pushback and Powerback 2
Taxi Instructions 2
Pre-Departure Manoeuvring 5
Take-Off Clearance 6
Aerodrome Traffic Circuit 10
Final Approach and Landing 13

17 November 2011

Missed Approach 15
Runway Vacating and Communicating after Landing 16
Essential Aerodrome Information 16
Arrestor Systems at Military Aerodromes 17

Aerodrome Flight Information Service Phraseology 18

Introduction 18

Contents Page 2

CAP 413 Radiotelephony Manual

Type of Service 18
AFIS Phraseology for Ground Movement, Take-Off,

Landing and Transit 19

Aerodrome Phraseology for Helicopters 23

Introduction 23
Helicopter Callsigns 23
Helicopter Phraseology for Taxiing 23
Helicopter Phraseology for Take-Off and Landing (ATC only) 24
Helicopter Hover Phraseology Examples (ATC and AFIS only) 24
Helicopter Taxiing Phraseology Examples (ATC and AFIS only) 25
Helicopter Take-Off and Landing Phraseology Examples

(ATC only) 25

Aerodrome Phraseology for Vehicles (ATC and AFIS only) 27

Introduction 27
Movement Instructions 27
To Cross a Runway 29
Vehicles Towing Aircraft 30
Low Visibility Procedures 31
Messages regarding Safety of an Aircraft 31
Messages regarding Wildlife 31
Driver unsure of Position 31
Broken-down Vehicle 31
Radio Failure 31

Aerodrome Air/Ground Communication Service Phraseology 32

Introduction 32
Type of Service 32
Air/Ground Station Identification 32
Phraseology and Examples 32
Offshore Communication Service 36

Radiotelephony Reports at Unattended Aerodromes 39

Introduction 39
Additional Procedures for the Use of SAFETYCOM 39
Unattended Aerodrome Phraseology Examples 40

Aerodrome Information 42

17 November 2011

Meteorological Conditions 42
Voice Weather Broadcast (VOLMET) UK 42
Runway Visual Range (RVR)/Visibility 43
Runway Surface Conditions 44
Automatic Terminal Information Service (ATIS) UK 46

Contents Page 3

CAP 413 Radiotelephony Manual

Chapter 5 Radar Phraseology

General 1

Introduction 1
Radar Identification of Aircraft 1
Secondary Surveillance Radar Phraseology 2
ATS Surveillance Service 4
Radar Vectoring 5
Traffic Information and Avoiding Action Phraseology 6
ACAS/TCAS Phraseology 8
Communications and Loss of Communications 8
Essential Traffic Information 9
Danger Area Crossing Service/Danger Area Activity Information

Service 9

Chapter 6 Approach Phraseology

Approach Control Service Phraseology 1

IFR Departures 1
VFR Departures 2
IFR Arrivals 3
VFR Arrivals 7
Special VFR Flights 8
Vectoring to Final Approach 9
Direction Finding (DF) 12
VDF Procedure 13
NDB(L) and VOR Procedures 17
Area Navigation Global Navigation Satellite System RNAV (GNSS)

Phraseology 20
Surveillance Radar Approach (SRA) 21
Landing Altimeter Setting (QNE) 24
PAR Approach 24
Clearance to enter Control Zones (CTR) 24
Aerodrome Traffic Zone (ATZ) associated with another

Aerodrome 25
Lower Airspace Radar Service (LARS) 25
Air Traffic Services Outside Controlled Airspace (ATSOCAS) 26

Chapter 7 Area Phraseology

Area Control Service Phraseology 1

General 1
Position Reporting 1
Flights Joining Airways 2
Flights Leaving Airways 2

17 November 2011

Contents Page 4

CAP 413 Radiotelephony Manual

Flights Crossing Airways 3
Flights Holding En-Route 3
Reduced Vertical Separation Minimum (RVSM) Phraseology 4

Chapter 8 Emergency Phraseology

Distress and Urgency Communication Procedures 1

Introduction 1
States of Emergency 1
UHF and VHF Emergency Service 1
UHF and VHF Emergency Service – General Procedures 2
Emergency Message 3
Ejection from Aircraft 4
Ballistic Recovery Systems 4
Speechless Code 4
Radio Procedures – Practice Emergencies 5
Training Fix 5
Relayed Emergency Message 6
Imposition of Silence 6
Emergency Descent 7
Termination of Distress Communications and of RTF Silence 7

Chapter 9 Miscellaneous Phraseology

Other Communications 1

Wake Turbulence 1
Wind Shear 1
AIRPROX Reporting 2
Oil Pollution Reporting 2
Interceptions by Military Aircraft 3
Aircraft Operating Agency Messages 3
Use of ATS Frequencies for Aircraft Operating Agency

Messages 4

8.33 kHz Phraseology 4
Operations by aircraft deploying brake chutes 5
Mareva Injunctions 6
CPDLC Failure 7
Aerodrome Emergency Services 7

Chapter 10 Military Specific Phraseology

Military Specific Phraseology 1
Military Variances to Chapter 2 1

Transmission of UHF Channels 1
Transmission of Time 1

17 November 2011

Contents Page 5

CAP 413 Radiotelephony Manual

Standard Words and Phrases 1
Communications 2
RT Phraseology When Using SSR 2

Military Specific Procedures (Control of Aircraft) 2

NATO Standard Visual Circuit Procedures 2
NATO Studs and Common VHF Frequencies 2
Weather and Aerodrome Information 3
Cancellation of Take-Off 4
Phraseology for Joining the Visual Circuit/Pattern 4
Landing Gear Position 5
Arrestor System Procedures and Phraseology 5
Phraseology for Fixed-Wing VTOL Operations 8
Emergency Messages 8
Flameout/Engine Failure – Aerodrome Phraseology 8
PAR Phraseology 9
PAR Azimuth Only/SRA Phraseology 11
ILS Phraseology 12
Descent to Low Level 14
Jamming phraseology 14
Speechless Procedures 14
Military Missed Approach 16
Suspension of RT Procedures 17
Formations in Trail 17
Contact Lost 17
Freecall and Continue With 17
Aerobatics and General Handling 18
Passing the Number of Persons on Board (POB) 18
Clearances with an Occupied Runway 18
Formation Clearances 19
TACAN Specific Phraseology 19
Radar PFL 20
Controlled Descent through Cloud (QGH) 20
Flameout Spiral Descent 23
No Compass/No Gyro 25
Supersonic Flight 25

17 November 2011

Military Aerodrome Traffic Zones (MATZ) and
Penetration Services 26

Military Safety Broadcast – Securité 27

Contents Page 6

CAP 413 Radiotelephony Manual

Chapter 11 Phraseology Examples

Examples of Types of Flights 1

Introduction 1
An IFR Flight 2
A VFR/IFR Flight 17
Flight in the Military Visual Circuit 24
Flight Receiving Lower Airspace Radar Service (LARS)

and Danger Area Crossing Service (DACS) 28
Callsign Prefix – 'STUDENT' 30
Flight Receiving Avoiding Action 31
Flight Receiving En-Route Basic Service 32
Flight Transmitting a Practice Pan 33
Arrival Flight (Aerodrome FIS) 35

Appendix 1 UK Differences to ICAO Radiotelephony Procedures

Appendix 2 UK Civil/Military Radiotelephony Differences

Bibliography

Index

17 November 2011

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CAP 413 Radiotelephony Manual

Explanatory Note

Twentieth Edition, Amendment 1: Summary

In addition to editorial changes and minor corrections, and a change throughout the document
from millibar to hectopascal as the unit of measurement of atmospheric pressure,
Amendment 1 comprises:

Section Chapter Paragraph Subject Origin

Glossary 1 1.1 Addition of definition for Backtrack,

and removal of Absolute Minima.

Radiotelephony 2 1.14.5 Readback requirement of altimeter

settings, including units when value is
below 1000 hectopascals.

Aerodrome
Phraseology

Aerodrome
Phraseology

Aerodrome
Phraseology

Aerodrome
Phraseology

Aerodrome
Phraseology

Aerodrome
Phraseology

Approach
Phraseology

4 1.8.7 Expansion of examples for circuit

phraseology.

4 1.9.6 Example phraseology for a low pass. CAA

4 1.12 Correction to phraseology for

reduction in RFFS.

4 2.3.2 Enhanced text for FISO phraseology

regarding use of runway designators.

4 5.5.2 Passing of traffic information, and

logistics information by an offshore
aeronautical radio station.

4 7.3 Removal of Absolute Minimum and

addition of ‘check your minima’.

6 1.4.1 Correction to example of pilot

readback of VFR clearance.

CAA

CAA

CAA

CAA

CAA

CAA

CAA

CAA

Approach
Phraseology

Emergency
Phraseology

Phraseology
Examples

Appendix 1 2 & 3 Update of UK differences to ICAO.

Bibliography 1 JSP 552 Military Air Traffic Service

17 November 2011

6 1.17.6 Addition of example for reducing a

service due to surveillance
performance.

8 1.7 Addition of phraseology for use of

Ballistic Recovery System.

11 1.2.5 Correction to phraseology for

'descend on the glidepath'.

Hectopascals and 'Negative I say
again’ now in use.

Regulations renamed ATM 3000
Manual of Military Air Traffic
Management.

Explanatory Note Page 1

MAA

CAA

CAA

CAA

MAA

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CAP 413 Radiotelephony Manual

Revision History

Revisions included in Edition 20 31 March 2011

In addition to editorial changes and minor corrections, Edition 20 comprises:

Glossary Addition of Clearance Delivery Officer and Combined Military

Aerodrome Traffic Zone.

Radiotelephony ‘Negative I say again’ and ‘Recleared’ added.

Clearance Delivery added.

Abbreviated Callsigns added.

Expansion of Clearance Issue and Read Back Requirements.

General Phraseology Rewording of Pilot Response to ATC Instructions.

Rewording of Passing Message Details.

Aerodrome Phraseology Addition of phraseology for crossing unserviceable stop-bars.

Addition of phraseology for cancelling a landing clearance, when
reissue is anticipated in good time for a safe landing.

Use of Tow Approved added.

Radar Phraseology Barometric Pressure Setting Tool added.

ACAS/TCAS phraseology is unchanged, however entry is rewritten.

Approach Phraseology Transmit for DF added.

Miscellaneous Phraseology Revised Phraseology for depletion of Aerodrome Emergency

Services.

Revisions included in Amendment 1 to Edition 20 17 November 2011

In addition to editorial changes and minor corrections, and a change throughout the document
from millibar to hectopascal as the unit of measurement of atmospheric pressure,
Amendment 1 to Edition 20 comprises:

Glossary Addition of definition for Backtrack, and removal of Absolute

Minima.

Radiotelephony Readback requirement of altimeter settings, including units when

value is below 1000 hectopascals.

Aerodrome Phraseology Expansion of examples for circuit phraseology.

Example phraseology for a low pass.

Correction to phraseology for reduction in RFFS.

Enhanced text for FISO phraseology regarding use of runway
designators.

Passing of traffic information, and logistics information by an
offshore aeronautical radio station.

Removal of Absolute Minimum and addition of ‘check your minima’.

17 November 2011

Revision History Page 1

CAP 413 Radiotelephony Manual

Approach Phraseology Correction to example of pilot readback of VFR clearance.

Addition of example for reducing a service due to surveillance
performance.

Emergency Phraseology Addition of phraseology for use of Ballistic Recovery System.

Phraseology Examples Correction to phraseology for 'descend on the glidepath'.

Appendix 1 Update of UK differences to ICAO. Hectopascals and 'Negative I

say again' now in use.

Bibliography JSP 552 Military Air Traffic Service Regulations renamed ATM 3000

Manual of Military Air Traffic Management.

17 November 2011

Revision History Page 2

CAP 413 Radiotelephony Manual

Foreword

1 Document Description

1.1 Document Purpose

1.1.1 The aim of the United Kingdom Radiotelephony Manual (CAP 413) is to provide pilots,
Air Traffic Services personnel and other ground personnel, both civil and military, with
a compendium of clear, concise, standardised phraseology and associated guidance,
for radiotelephony (RTF) communication in United Kingdom airspace.

1.2 Document Applicability

1.2.1 All users of RTF in the United Kingdom are expected to comply with the phraseology
described in this manual.

1.2.2 Chapter 10 of this Manual details Military Specific Phraseology for specific use
by military ATCOs and military aircrew. The RTF described in Chapter 10 is
complementary to NATO STANAG 3817. It is also complementary to the remainder
of CAP 413, as it either differs from civil phraseology or there is no equivalent civil
phraseology, e.g. in the case of arrestor system procedures.

1.2.3 Civil pilots visiting military aerodromes will be expected to be aware of the military
phraseology in Chapter 10 and to comply with such instructions as may be issued by
military controllers during their visit. Where relevant, cross references from the
remainder of CAP 413 to the equivalent military phraseology are provided for the
assistance of civil pilots visiting military aerodromes.

1.2.4 Operational details can be found in the United Kingdom Aeronautical Information
Publication (UK AIP). Phraseology for air traffic controllers (consistent with CAP 413)
is also published in the Manual of Air Traffic Services (CAP 493).

1.2.5 CAP 413 is also a useful reference for those studying for the UK Flight
Radiotelephony Operator's Licence.

1.2.6 Candidates for JAA pilot and instrument rating examinations should note that the
syllabus for the communications examination is drawn directly from the International
Civil Aviation Organisation (ICAO) Annex 10 Volume 2 and ICAO Doc 9432-AN/925
and not CAP 413.

1.3 Document Source

1.3.1 The UK RTF Manual is based on ICAO Annex 10 Volume 2 (Communications
Procedures) to the Convention on International Civil Aviation and ICAO PANS-ATM
(Procedures for Air Navigation Services - Air Traffic Management) Doc. 4444.

1.3.2 Where the ICAO standard phraseology may be misunderstood, or has weaknesses in
the UK environment, different phraseology has been specified (and notified to ICAO).
Significant differences between the ICAO standard phraseology and that specified for
use in CAP 413 are described in Appendix 1 to this publication.

1.4 Document Format

1.4.1 Examples of phraseology in CAP 413 are intended to be representative of
communications in common use. The initial call in a series of messages is shown on
the left side of the page; subsequent messages appear in chronological order on the
right side of the page.

1.4.2 Black text and grey-scale illustrations are used to facilitate printing on monochrome
printers.

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Foreword Page 1

CAP 413 Radiotelephony Manual

1.4.3 The agency making the transmission is identified by the line style of the frame and a
representative symbol (e.g. Aircraft) as follows:

AIRCRAFT

VEHICLE

GROUND STATION
(ATC, AFIS, AGCS)

1.4.4 In this document the following protocol is used:
a) The words 'must' or 'shall' indicate that compliance is compulsory.
b) The word 'should' indicates a recommendation.
c) The word 'may' indicates an option.
d) The word 'will' is used to express the future.

1.4.5 Any reference in this document to the male gender should be understood to include
both male and female persons.

1.5 Document Revisions

1.5.1 Major changes to RTF phraseology are notified by issuing an Aeronautical Information
Circular (AIC). Revisions to CAP 413 are published at regular intervals.

1.5.2 Regular users of CAP 413 may wish to consider subscribing to the AIC Amendment
Service in order to maintain the currency of this publication. Details of this service
may be obtained from the Civil Aviation Authority at the address shown on the inside
front cover of this document.

1.5.3 When appropriate, loose-leaf amendments to this publication will be issued for
insertion to the main document. When significant changes occur the document will
be reissued as a new edition. The edition number and amendment status of the
current version are shown inside the front cover.

1.5.4 When issuing amendments or a new edition, significant changes to the text are
indicated by the use of sideline revision marks.

1.5.5 The revision date of an individual page can be determined from the date shown at the
left footer. When a new edition is published, all pages will indicate the effective date
of the complete edition.

1.5.6 Individual Chapters in this publication are separately numbered to allow for the issue
of amendment pages, without the need to renumber and reissue the entire
document.

1.6 Document Availability

1.6.1 CAP 413 is available from the Civil Aviation Authority website at www.caa.co.uk/
cap413. Visitors to the website may view, download and reproduce this file for use
by their company or organisation, or for their own personal use.

1.6.2 Printed copies of CAP 413 are available for purchase from the CAA's sales agency for
printed publications. Contact details are provided on the inside cover of this
publication.

1.7 Document Comments and Queries

1.7.1 Should readers have any comments or queries regarding the contents of this
document, they should contact the editor at the address provided on the inside cover
of the publication.

31 March 2011

Foreword Page 2

CAP 413 Radiotelephony Manual

Chapter 1 Glossary

1 Terms

1.1 Definitions

Advisory Area A designated area where air traffic advisory service is available.
Advisory Route A designated route along which air traffic advisory service is

available (ICAO).
Aerodrome Any area of land or water designed, equipped, set apart or commonly

used for affording facilities for the landing and departure of aircraft and includes any
area or space, whether on the ground, on the roof of a building or elsewhere, which
is designed, equipped or set apart for affording facilities for the landing and departure
of aircraft capable of descending or climbing vertically, but shall not include any area
the use of which for affording facilities for the landing and departure of aircraft has
been abandoned and has not been resumed (ANO).

Aerodrome Control Service Air traffic control service for aerodrome traffic.
Commission Regulation (EC) 549/2004.

Aerodrome Flight Information Service (AFIS) A flight information service provided
to aerodrome traffic.

Aerodrome Operating Minima In relation to the operation of an aircraft at an
aerodrome means the cloud ceiling and runway visual range for take-off, and the
decision height or minimum descent height, runway visual range and visual reference
for landing, which are the minimum for the operation of that aircraft at that aerodrome
(ANO).

Aerodrome Traffic All traffic on the manoeuvring area of an aerodrome and all
aircraft flying in the vicinity of an aerodrome (ICAO).

Aerodrome Traffic Zone Has the meaning assigned to it by Article 156, ANO 2005.
Aeronautical Mobile Service A mobile service between aeronautical stations and

aircraft stations, or between aircraft stations, in which survival craft stations may
participate; emergency position-indicating radio beacon stations may also participate
in this service on designated distress and emergency frequencies (ICAO).

Aeronautical Station A land station in the aeronautical mobile service. In certain
instances, an aeronautical station may be located, for example, on board ship or on a
platform at sea (ICAO).

Airborne Collision Avoidance System (ACAS) An aircraft system based on SSR
transponder signals which operates independently of groundbased equipment to
provide advice to the pilot on potential conflicting aircraft that are equipped with SSR
transponders.

Aircraft Station A mobile station in the aeronautical mobile service on board an
aircraft.

Air-ground Communications Two-way communication between aircraft and
stations or locations on the surface of the earth (ICAO).

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Air/Ground Communication Service A service provided from an aerodrome to
give information to pilots of aircraft flying in the vicinity of the aerodrome by means of
radio signals and ‘air/ground communications service unit’ shall be construed
accordingly (ANO).

AIRPROX A situation in which, in the opinion of a pilot or controller, the distance
between aircraft as well as their relative positions and speed have been such that the
safety of the aircraft involved was or may have been compromised (ICAO).

Air Traffic All aircraft in flight or operating on the manoeuvring area of an aerodrome
(ICAO).

Air Traffic Control Clearance Authorisation for an aircraft to proceed under
conditions specified by an air traffic control unit (ICAO).

Air Traffic Service (ATS) A generic term meaning variously: flight information
service, alerting service, air traffic advisory service, air traffic control service, (area
control service, approach control service or aerodrome control service) (ICAO).

Airway A control area or portion thereof established in the form of a corridor (ICAO).
Altitude The vertical distance of a level, a point or an object considered as a point,

measured from mean sea level (ICAO).
Area Control Centre An air traffic control unit established to provide an area control

service to aircraft flying within a notified flight information region which are not
receiving an aerodrome control service or an approach control service (ANO).

ATS Surveillance Service A service provided directly by means of an ATS
surveillance system (ICAO).

Automatic Terminal Information Service (ATIS) The automatic provision of
current, routine information to arriving and departing aircraft throughout 24 hours or a
specified portion thereof (ICAO).

Backtrack To taxi on a runway-in-use, in the opposite direction to the aircraft's take­off or landing direction.

Base Turn A turn executed by the aircraft during the initial approach between the
end of the outbound track and the beginning of the intermediate or final approach
track. The tracks are not reciprocal (ICAO).

Basic Service A Basic Service is an ATS provided for the purpose of giving advice
and information useful for the safe and efficient conduct of flights. This may include
weather information, changes of serviceability of facilities, conditions at aerodromes,
general airspace activity information, and any other information likely to affect safety.
The avoidance of other traffic is solely the pilot’s responsibility.

Blind Transmission A transmission from one station to another station in
circumstances where two-way communication cannot be established but where it is
believed that the called station is able to receive the transmission (ICAO).

Broadcast A transmission of information relating to air navigation that is not
addressed to a specific station or stations (ICAO).

Clearance Limit The point to which an aircraft is granted an air traffic control
clearance. A clearance limit shall be described by specifying the name of the
appropriate significant point, or aerodrome or controlled airspace boundary (ICAO).

Control Area Controlled airspace which has been further notified as a control area
and which extends upwards from a notified altitude or flight level (ANO).

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Controlled Airspace Airspace which has been notified as Class A, Class B, Class C,
Class D or Class E airspace (ANO).

Control Zone Controlled airspace which has been further notified as a control zone
and which extends upwards from the surface (ANO).

Cruising Level A level maintained during a significant portion of a flight (ICAO).
Decision Altitude/Height In relation to the operation of an aircraft at an aerodrome

means a specified altitude/height in a precision approach at which a missed approach
must be initiated if the required visual reference to continue the approach to land has
not been established (ANO).

Deconfliction Service. A Deconfliction Service is a surveillance based ATS where,
in addition to the provisions of a Basic Service, the controller provides specific
surveillance derived traffic information and issues headings and/or levels aimed at
achieving planned deconfliction minima against all observed aircraft in Class F/G
airspace, or for positioning and/or sequencing. However, the avoidance of other traffic
is ultimately the pilot’s responsibility.

Elevation The vertical distance of a point or level on, or affixed to, the surface of the
earth measured from mean sea level (ICAO).

Estimated Time of Arrival For IFR flights, the time at which it is estimated that the
aircraft will arrive over that designated point, defined by reference to navigation aids,
from which it is intended that an instrument approach procedure will be commenced,
or, if no navigation aid is associated with the aerodrome, the time at which the aircraft
will arrive over the aerodrome. For VFR flights, the time at which it is estimated that
the aircraft will arrive over the aerodrome (ICAO).

Flight Information Service Officer (FISO) A Flight Information Service Officer at
any aerodrome or area control centre.

Flight Level One of a series of levels of equal atmospheric pressure, separated by
notified intervals and each expressed as the number of hundreds of feet which would
be indicated at that level on a pressure altimeter calibrated in accordance with the
International Standard Atmosphere and set to 1013.2 hectopascals (ANO).

Flight Plan Specified information provided to air traffic services units, relative to an
intended flight or portion of a flight of an aircraft (ICAO).

General Air Traffic Flights operating in accordance with civil air traffic procedures.
Heading The direction in which the longitudinal axis of an aircraft is pointed, usually

expressed in degrees from North (true, magnetic, compass or grid) (ICAO).
Height The vertical distance of a level, a point, or an object considered as a point

measured from a specified datum (ICAO).
Holding Point A speech abbreviation used in radiotelephony phraseology having

the same meaning as Taxiway Holding Position or Runway Holding Position.
Identification The situation which exists when the position indication of a particular

aircraft is seen on a situation display and positively identified (ICAO).

IFR Flight A flight conducted in accordance with the Instrument Flight Rules (RoA).
Instrument Meteorological Conditions (IMC) Weather precluding flight in

compliance with the Visual Flight Rules (ANO).
Known Traffic Traffic, the current flight details and intentions of which are known

to the controller concerned through direct communication or co-ordination.

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Level A generic term relating to the vertical position of an aircraft in flight and
meaning variously: height, altitude or flight level (ICAO).

Level Bust Any deviation from assigned altitude, height or flight level in excess of
300 feet.

Microwave Approach An approach executed by an aircraft, utilising a Microwave
Landing System (MLS) for guidance.

Minimum Descent Altitude/Height In relation to the operation of an aircraft at an
aerodrome means the altitude/height in a non-precision approach below which
descent may not be made without the required visual reference (ANO).

Missed Approach Point (MAPt) The point in an instrument approach procedure at
or before which the prescribed missed approach procedure must be initiated in order
to ensure that the minimum obstacle clearance is not infringed.

Missed Approach Procedure The procedure to be followed if the approach cannot
be continued (ICAO).

Procedural Service A Procedural Service is an ATS where, in addition to the
provisions of a Basic Service, the controller provides vertical, lateral, longitudinal and
time instructions, which if complied with, shall achieve deconfliction minima against
other aircraft participating in the Procedural Service. Neither traffic information nor
deconfliction advice can be passed with respect to unknown traffic.

Procedure Turn A manoeuvre in which a turn is made away from a designated track
followed by a turn in the opposite direction to permit the aircraft to intercept and
proceed along the reciprocal of the designated track (ICAO).

Radar Approach An approach in which the final approach phase is executed under
the direction of a controller using radar (ICAO).

Radar Contact The situation which exists when the radar position of a particular
aircraft is seen and identified on a situation display (ICAO).

Reporting Point A specified geographical location in relation to which the position
of an aircraft can be reported (ICAO).

Runway A defined rectangular area on a land aerodrome prepared for the landing
and take-off of aircraft (ICAO).

Runway Visual Range The range over which the pilot of an aircraft on the centre
line of a runway can expect to see the runway surface markings, or the lights
delineating the runway or identifying its centre line (ICAO).

SAFETYCOM A common frequency (135.475MHz) made available for use at
aerodromes where no other frequency is allocated, to enable pilots to broadcast their
intentions to other aircraft that may be operating on, or in the vicinity of, the
aerodrome.

Signal Area An area on an aerodrome used for the display of ground signals.
Significant Point A specified geographical location used in defining an ATS route

or the flight path of an aircraft and for other navigational and ATS purposes (ICAO).
Special VFR Flight A flight made at any time in a control zone which is Class A

airspace or is in any other control zone in IMC or at night, in respect of which the
appropriate air traffic control unit has given permission for the flight to be made in
accordance with special instructions given by that unit, instead of in accordance with
the Instrument Flight Rules and in the course of which flight the aircraft complies with
any instructions given by that unit and remains clear of cloud and with the surface in
sight (RoA).

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Straight Ahead When used in departure clearances means: ‘track extended
runway centre-line’. When given in Missed Approach Procedures means: ‘continue
on Final Approach Track’.

Terminal Control Area A control area normally established at the confluence of
airways in the vicinity of one or more major aerodromes (ICAO).

Threshold The beginning of that portion of the runway useable for landing (ICAO).
Traffic Alert and Collision Avoidance System (TCAS) See Airborne Collision

Avoidance System (ACAS).
Traffic Service A Traffic Service is a surveillance ATS, where in addition to the

provisions of a Basic Service, the controller provides specific surveillance derived
traffic information to assist the pilot in avoiding other traffic. Controllers may provide
headings and/or levels for the purposes of positioning and/or sequencing; however,
the controller is not required to achieve deconfliction minima, and the avoidance of
other traffic is ultimately the pilot’s responsibility.

Vectoring Provision of navigational guidance to aircraft in the form of specific
headings, based on the use of an ATS surveillance system (ICAO).

VFR Flight A flight conducted in accordance with the visual flight rules (RoA).
Visual Meteorological Conditions (VMC) Weather permitting flight in accordance

with the Visual Flight Rules (ANO).

1.2 Abbreviations

1.2.1 The following abbreviations are those in common use in the United Kingdom. If RTF
transmission of an abbreviation is required, and the format is not specified in this
document, the format specified by ICAO (see ICAO PANS-ABC Doc. 8400) should be
used. If no format is defined, the abbreviation should be described using the phonetic
alphabet.

1.2.2 The abbreviations annotated with an asterisk are normally spoken as complete words.
The remainder are normally spoken using the constituent letters rather than the
spelling alphabet. Military abbreviations are marked with '(M)'.

A

AAIB Air Accident Investigation Branch
aal Above Aerodrome Level
ACAS* Airborne Collision Avoidance System (pronounced A-kas) (see TCAS)
ACC Area Control Centre
ADF Automatic Direction-Finding Equipment
ADR Advisory Route
ADT Approved Departure Time
AEF Air Experience Flight (M)
AFTN Aeronautical Fixed Telecommunication Network
AFIS Aerodrome Flight Information Service
AGCS Air Ground Communication Service
agl Above Ground Level

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AIC Aeronautical Information Circular
AIP Aeronautical Information Publication
AIRPROX* Aircraft Proximity (replaces Airmiss/APHAZ)
AIS Aeronautical Information Services
amsl Above Mean Sea Level
ANO Air Navigation Order
APAPI Abbreviated Precision Approach Path Indicator (pronounced Ay-PAPI)
ATA Actual Time of Arrival
ATC Air Traffic Control (in general)
ATCO* Air Traffic Control Officer (M)
ATD Actual Time of Departure
ATIS* Automatic Terminal Information Service
ATS Air Traffic Service
ATSU Air Traffic Service Unit
ATSOCAS Air Traffic Services outside Controlled Airspace
AT-VASIS Abbreviated T Visual Approach Slope Indicator System (pronounced Ay-

Te e- VAS IS )

ATZ Aerodrome Traffic Zone

C

CAA Civil Aviation Authority
CAVOK* Visibility, cloud and present weather better than prescribed values or

conditions (CAVOK pronounced Cav-okay)
C/S Callsign
CDO Clearance Delivery Officer
CMATZ Combined Military Aerodrome Traffic Zone
CPDLC Controller Pilot Data Link Communication (pronounced See Pee Dee Ell

See) - A means of communication between a controller and aircrew using

data link in conjuction with or instead of voice, for ATC.
CTA Control Area
CTR Control Zone

D

DAAIS* Danger Area Activity Information Service (DAAIS pronounced DAY-ES)
DACS* Danger Area Crossing Service
DF Direction Finding

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DME Distance Measuring Equipment
DR Dead Reckoning

E

EAT Expected Approach Time
ETA Estimated Time of Arrival
ETD Estimated Time of Departure
EGNOS* European geostationary navigation overlay service

F

FAF Final Approach Fix
FIR Flight Information Region
FTU Flying Training Unit (M)
FISO* Flight Information Service Officer
FL Flight Level
Ft Foot (feet)

G

GAT General Air Traffic
GBAS* Ground-based augmentation system (pronounced GEE-BAS)
GS Gliding School (M)
GLONASS* Global Orbiting Navigation Satellite System (pronounced Glo-NAS)
GMC Ground Movement Control
GNSS Global Navigation Satellite System
GPS Global Positioning System
GRAS* Ground-based regional augmentation system (pronounced GRASS)

H

H24 Continuous day and night service (H24 pronounced Aitch Twenty Fower)
HF High Frequency
HJ Sunrise to Sunset
HN Sunset to Sunrise
hPa Hectopascal

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I

IAF Initial Approach Fix
IAS Indicated Air Speed
ICAO* International Civil Aviation Organisation
IF Intermediate Approach Fix
IFR Instrument Flight Rules
ILS Instrument Landing System
IMC Instrument Meteorological Conditions
IRVR Instrumented Runway Visual Range

K

Kg Kilogramme(s)
kHz Kilohertz
Km Kilometre(s)
kt Knot(s)

M

MAPt Missed Approach Point
MATZ* Military Aerodrome Traffic Zone

MDA/H Minimum Descent Altitude/Height
MEDA* Military Emergency Diversion Aerodrome
MET* Meteorological or Meteorology
METAR* Routine aviation aerodrome weather report
MHz Megahertz
MLS Microwave Landing System
MOR Mandatory Occurrence Report

N

NATS* National Air Traffic Services
NDB Non-Directional Radio Beacon

O

OAC Oceanic Area Control Unit
OCA Oceanic Control Area

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OCA/H Obstacle Clearance Altitude/Height
OPC Operational Control Communications
OCU Operational Conversion Unit (M)

P

PAPI* Precision Approach Path Indicator (pronounced PAPI)
POB (Total) Persons on Board
PAR Precision Approach Radar (M)

Q

QDM Magnetic heading (zero wind) (Sometimes employed to indicate

magnetic heading of a runway)
QDR Magnetic bearing
QFE Altimeter subscale setting to indicate height above either aerodrome

elevation, or threshold elevation, or helideck elevation
QNE Landing altimeter reading when subscale set 1013 hectopascals
QNH Altimeter subscale setting to indicate elevation (AMSL) when on the

ground and altitude in the air
QTE True Bearing

R

RA Resolution Advisory (see TCAS)
RCC Rescue Co-ordination Centre
RPS Regional Pressure Setting
RTF Radiotelephone/Radiotelephony
RVR Runway Visual Range
RVSM Reduced Vertical Separation Minima (pronounced Ahh Vee Ess Emm)

S

SAR Search and Rescue
SBAS* Satellite-based augmentation system (pronounced ESS-BAS)
SID* Standard Instrument Departure
SIGMET* Significant information concerning en-route weather phenomena which

may affect the safety of aircraft operations
SRA Surveillance Radar Approach
SSR Secondary Surveillance Radar

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STANAG* Standing Agreement (M)
STAR* Standard Instrument Arrival

T

TA Traffic Advisory (see TCAS)
TAF* Terminal Aerodrome Forecast
TCAS* Traffic Alert and Collision Avoidance System (pronounced Tee-kas) (see

ACAS)
TMA Terminal Control Area
T-VASIS T Visual Approach Slope Indicator System (pronounced TEE-VASIS)
TWU Tactical Weapons Unit (M)

U

UAS Upper Airspace
UAS University Air Squadron (M)
UHF Ultra-High Frequency
UIR Upper Flight Information Region
USAF United States Air Force (M)
UTC Co-ordinated Universal Time

V

VASIS* Visual Approach Slope Indicator System (pronounced VASIS)
VDF Very High Frequency Direction-Finding Station
VFR Visual Flight Rules
VHF Very High Frequency (30 to 300 MHz)
VMC Visual Meteorological Conditions
VOLMET* Meteorological information for aircraft in flight
VOR VHF Omnidirectional Radio Range
VORTAC* VOR and TACAN combination

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Chapter 2 Radiotelephony

1 General Procedures

1.1 Introduction
Radiotelephony provides the means by which pilots and ground personnel

communicate with each other. Used properly, the information and instructions
transmitted are of vital importance in assisting in the safe and expeditious operation
of aircraft. However, the use of non-standard procedures and phraseology can cause
misunderstanding. Incidents and accidents have occurred in which a contributing
factor has been the misunderstanding caused by the use of non-standard
phraseology. The importance of using correct and precise standard phraseology

cannot be over-emphasised.

1.2 Transmitting Technique

1.2.1 The following transmitting techniques will assist in ensuring that transmitted speech
is clearly and satisfactorily received.

a) Before transmitting check that the receiver volume is set at the optimum level and

listen out on the frequency to be used to ensure that there will be no interference
with a transmission from another station.

b) Be familiar with microphone operating techniques and do not turn your head away

from it whilst talking or vary the distance between it and your mouth. Severe
distortion of speech may arise from:

i) talking too close to the microphone;
ii) touching the microphone with the lips; or

iii) holding the microphone or boom (of a combined headset/microphone system).
c) Use a normal conversation tone, speak clearly and distinctly.
d) Maintain an even rate of speech not exceeding 100 words per minute. When it is

known that elements of the message will be written down by the recipients, speak

at a slightly slower rate.
e) Maintain the speaking volume at a constant level.
f) A slight pause before and after numbers will assist in making them easier to

understand.
g) Avoid using hesitation sounds such as ‘er’.
h) Avoid excessive use of courtesies and entering into non-operational conversations.
i) Depress the transmit switch fully before speaking and do not release it until the

message is complete. This will ensure that the entire message is transmitted.

However, do not depress transmit switch until ready to speak.
j) Be aware that the mother tongue of the person receiving the message may not be

k) Messages should not contain more than three specific phrases, comprising a

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English. Therefore, speak clearly and use standard radiotelephony (RTF) words and

phrases wherever possible.

clearance, instruction or pertinent information. In cases of doubt, e.g. a foreign

pilot having difficulty with the English language or an inexperienced pilot unsure of

the procedures, the controller should reduce the number of items and if necessary

these should be passed, and acknowledged, singly.

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1.2.2 One of the most irritating and potentially dangerous situations in radiotelephony is a
‘stuck’ microphone button. Operators should always ensure that the button is
released after a transmission and the microphone placed in an appropriate place that
will ensure that it will not inadvertently be switched on.

1.2.3 After a call has been made, a period of at least 10 seconds should elapse before a
second call is made. This should eliminate unnecessary transmissions while the
receiving station is getting ready to reply to the initial call.

1.3 Transmission of Letters

1.3.1 The words in the table below shall be used when individual letters are required to be
transmitted. The syllables to be emphasised are underlined.

Table 1

Letter Word Appropriate pronunciation

A Alpha AL FAH

B Bravo BRAH VOH

C Charlie CHAR LEE

D Delta DELL TAH

E Echo ECK OH

F Foxtrot FOKS TROT

G Golf GOLF

H Hotel HOH TELL

I India IN DEE AH

J Juliett JEW LEE ETT

K Kilo KEY LOH

L Lima LEE MAH

M Mike MIKE

N November NO VEM BER

O Oscar OSS CAH

P Papa PAH PA H

Q Quebec KEH BECK

R Romeo ROW ME OH

S Sierra SEE AIR RAH

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T Tan go TANG GO

U Uniform YOU NEE FORM

V Victor VIK TAH

W Whiskey WISS KEY

X X-ray ECKS RAY

Y Ya n ke e YA NG KEE

Z Zulu ZOO LOO

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1.4 Transmission of Numbers

1.4.1 The syllables to be emphasised are underlined.

Table 2

Numeral or numeral
element

0 ZERO

1 WUN

2 TOO

3 TREE

4 FOWER

5 FIFE

6 SIX

7 SEVEN

8 AIT

9 NINER

Decimal DAYSEEMAL

Hundred HUN DRED

Thousand TOUSAND

Latin alphabet representation

1.4.2 All numbers, except those contained in paragraph 1.4.2 b) shall be transmitted by
pronouncing each digit separately as follows:

a) When transmitting messages containing aircraft callsigns, altimeter settings, flight

levels (with the exception of FL100, 200, 300 etc. which are expressed as ‘Flight
Level (number) HUN DRED’), headings, wind speeds/directions, pressure settings,
airspeed, transponder codes and frequencies, each digit shall be transmitted
separately; examples of this convention are as follows:

Table 3

Number Transmitted as Pronounced as

BAW246 Speedbird Two Four Six SPEEDBIRD TOO FOWER SIX

FL100 Flight Level One Hundred FLIGHT LEVEL WUN HUN DRED

FL180 Flight Level One Eight Zero FLIGHT LEVEL WUN AIT ZERO

150 Degrees One Five Zero Degrees WUN FIFE ZERO DEGREES

18 Knots One Eight Knots WUN AIT KNOTS

122.1 One Two Two Decimal One WUN TOO TOO DAYSEEMAL WUN

(Squawk) 6500 Six Five Zero Zero SIX FIFE ZERO ZERO

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b) All numbers used in the transmission of altitude, height, cloud height, visibility and

runway visual range information which contain whole hundreds and whole
thousands shall be transmitted by pronouncing each digit in the number of
hundreds or thousands followed by the word HUNDRED or TOUSAND as
appropriate. Combinations of thousands and whole hundreds shall be transmitted
by pronouncing each digit in the number of thousands followed by the word
TOUSAND and the number of hundreds followed by the word HUNDRED;
examples of this convention are as follows:

Table 4

Number Transmitted as Pronounced as

10 One Zero WUN ZERO

100 One Hundred WUN HUN DRED

2 500 Two Thousand Five Hundred TOO TOUSAND FIFE HUNDRED

11 000 One One Thousand WUN WUN TOUSAND

25 000 Two Five Thousand TOO FIFE TOUSAND

1.4.3 Numbers containing a decimal point shall be transmitted as prescribed in 1.4.1 with
the decimal point in appropriate sequence being indicated by the word decimal.

1.4.4 All six figures shall be used when identifying frequencies irrespective of whether they
are 25 kHz or 8.33 kHz spaced. Exceptionally, when the final two digits of the
frequency are both zero, only the first four digits need be given. In technical terms an

8.33 kHz frequency is referred to as a “channel”, however the word “channel” is not
used in RTF. Military phraseology for identifying UHF frequencies appears in Chapter
10 paragraph 2.1.

Table 5

Frequency Transmitted as Pronounced as

118.125 One One Eight Decimal One Two
Five

119.050 One One Nine Decimal Zero Five
Zero

122.500 One Two Two Decimal Five WUN TOO TOO DAY SEE MAL FIFE

118.000 One One Eight Decimal Zero WUN WUN AIT DAY SEE MAL

WUN WUN AIT DAY SEE MAL
WUN TOO FIFE

WUN WUN NINER DAY SEE MAL
ZERO FIFE ZERO

ZERO

1.4.5 When it is necessary to verify the accurate reception of numbers the person
transmitting the message shall request the person receiving the message to read
back the numbers.

1.5 Transmission of Time

1.5.1 When transmitting time, only the minutes of the hour are normally required.
However, the hour should be included if there is any possibility of confusion. Time
checks shall be given to the nearest minute and preceded by the word 'TIME'. Co­ordinated Universal Time (UTC) is to be used at all times, unless specified. 2400 hours
designates midnight, the end of the day, and 0000 hours the beginning of the day.

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Table 6

Number Transmitted as Pronounced as

0823 Two Three or Zero Eight Two

Three
1300 One Three Zero Zero WUN TREE ZERO ZERO
2057 Five Seven or Two Zero Five

Seven

1.6 Standard Words and Phrases
The following words and phrases shall be used in radiotelephony communications as

appropriate and shall have the meaning given below:

Table 7

Word/Phrase Meaning

ACKNOWLEDGE Let me know that you have received and understood this

message.
AFFIRM Ye s .
APPROVED** Permission for proposed action granted.
BREAK Indicates the separation between messages.
BREAK BREAK Indicates the separation between messages transmitted to

different aircraft in a busy environment.
NOTE: The phraseology “BREAK BREAK” may be confused with an instruction to an

aircraft formation and should be used with caution.

TOO TREE (or ZERO AIT TOO
TREE)

FIFE SEVEN (or TOO ZERO
FIFE SEVEN)

CANCEL Annul the previously transmitted clearance.
CHANGING TO I intend to call. . . (unit) on. . . (frequency).
CHECK Examine a system or procedure. (Not to be used in any other

context. No answer is normally expected.)
CLEARED ‡ Authorised to proceed under the conditions specified.
CLIMB ‡ Climb and maintain.
CONFIRM I request verification of: (clearance, instruction, action,

information).
CONTACT Establish communications with... (your details have been

passed).
CORRECT True or accurate.
CORRECTION An error has been made in this transmission (or message

indicated). The correct version is...
DESCEND ‡ Descend and maintain.
DISREGARD Ignore.
FAN STOP I am initiating a practice engine failure after take off. (Used only

by pilots of single engine aircraft.) The response should be,

“REPORT CLIMBING AWAY”.
FREECALL Call. . . (unit) (your details have not been passed – mainly used

by military ATC).

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Table 7 (Continued)

Word/Phrase Meaning

HOLD SHORT** Stop before reaching the specified location.

Note: Only used in limited circumstances where no defined

point exists (e.g. where there is no suitably located holding

point), or to reinforce a clearance limit.

HOW DO YOU READ What is the readability of my transmission?
I SAY AGAIN I repeat for clarity or emphasis.
MAINTAIN ‡ Continue in accordance with the condition(s) specified or in its

literal sense, e.g. “Maintain VFR”.
MONITOR Listen out on (frequency).
NEGATIVE No; or Permission not granted; or That is not correct; or Not

capable.
NEGATIVE I SAY AGAIN May be used if repeated incorrect readbacks are given by the

pilot and additional emphasis is required.
OUT* This exchange of transmissions is ended and no response is

expected.
OVER* My transmission is ended and I expect a response from you.
PASS YOUR MESSAGE Proceed with your message.
READ BACK Repeat all, or the specified part, of this message back to me

exactly as received.
RECLEARED To be used only in relation to routings and NOT for instructions

to climb or descend.
REPORT ** Pass requested information.
REQUEST I should like to know... or I wish to obtain...
ROGER I have received all your last transmission.

Note: Under no circumstances to be used in reply to a question

requiring a direct answer in the affirmative (AFFIRM) or

negative (NEGATIVE).

SAY AGAIN Repeat all, or the following part of your last transmission.
SPEAK SLOWER Reduce your rate of speech.
STANDBY Wait and I will call you.

Note: No onward clearance to be assumed. The caller would

normally re-establish contact if the delay is lengthy. STANDBY

is not an approval or denial.

UNABLE I cannot comply with your request, instruction or clearance.

Unable is normally followed by a reason.

WILCO I understand your message and will comply with it

(abbreviation for will comply)
WORDS TWICE As a request: Communication is difficult. Please send every

word twice.

As Information: Since communication is difficult, every word in

this message will be sent twice.

* Not normally used in U/VHF Communications.
** Not used by Air/Ground Communication Service Operators (c/s “Radio”).
‡ Not used by Air/Ground Communication Service Operators (c/s “Radio”) or Flight

Information Service Officers (c/s “Information”).

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1.7 Callsigns for Aeronautical Stations

1.7.1 Aeronautical stations are identified by the name of the location followed by a suffix
except that the name of the rig/platform/vessel is normally used by offshore mineral
extraction agencies. The suffix indicates the type of service being provided.

Table 8

Service Suffix

Area Control CONTROL

Radar (in general) RADAR

Approach Control APPROACH

Aerodrome Control TOWER

Approach Control Radar
Arrival/Departure

Ground Movement Control GROUND

Military Aerodrome Traffic
Zone (MATZ) Crossing

Precision Approach Radar TALKDOWN

Flight Information INFORMATION

Air/Ground Communication
Service

Clearance Delivery * DELIVERY

* Clearance Delivery Officer (CDO) positions may be established at aerodromes to relay

ATC departure clearances. Standard phraseology for CDO departure clearance is
referenced in Chapter 11, paragraph 1.2.2 A CDO shall not relay start, pushback, taxi, or
take off instructions.

DIRECTOR/DEPARTURE (RADAR – when tasks combined)/
ARRIVAL – (when approved))

ZONE

RADIO

NOTE: Lower Airspace Radar Service (LARS) is available from participating ATSUs

as described in UK AIP ENR 1.6.3.

1.7.2 There are three main categories of aeronautical communications service:

• Air Traffic Control Service (ATC) which can only be provided by licensed Air Traffic

Control Officers who are closely regulated by the relevant regulatory authority.

• Flight Information Service at aerodromes can be provided only by licensed Flight

Information Service Officers (FISOs), who are also regulated by the CAA.

• Aerodrome Air/Ground Communication Service (AGCS) which can be provided by

Radio Operators who are not licensed but have obtained a certificate of
competency to operate radio equipment on aviation frequencies from the CAA.
These operations come under the jurisdiction of the radio licence holder, but are
not regulated in any other way.

Other categories of aeronautical communications service include VOLMET, SIGMET,
Automatic Terminal Information Service (ATIS) or Aeronautical Information Services
(AIS).

1.7.3 It is an offence to use a callsign for a purpose other than that for which it has been
notified.

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1.7.4 The use of the calling aeronautical station’s callsign followed by the answering
aeronautical station’s callsign shall be considered the invitation to proceed with
transmission by the station calling. The use of the phrase ‘Pass your message’ may
be used when considered appropriate.

1.7.5 When satisfactory communication has been established, and provided that it will not
be confusing, the name of the location or the callsign suffix may be omitted.

1.7.6 Telephone procedures to be applied by civil controllers are published in CAP 493
(Manual of Air Traffic Services Part 1).

1.8 Callsigns for Aircraft

1.8.1 When establishing communication, an aircraft shall use the full callsigns of both
stations.

Borton Tower, G-ABCD, request
Basic Service

G-ABCD, Borton Tower, pass your

message

1.8.2 After satisfactory communication has been established and provided that no
confusion is likely to occur, the ground station may abbreviate callsigns (see table
below). A pilot may only abbreviate the callsign of his aircraft if it has first been
abbreviated by the aeronautical station.

Table 9

Full callsign Abbreviation

GBFRM G-RM

Speedbird GBGDC Speedbird DC

N31029 N029

N753DA N3DA

* Midland 640 No abbreviation

**Piper GBSZT Piper ZT

**Helicopter GABCD Helicopter CD

* Represents a Type C callsign.

** The name of either the aircraft manufacturer, or name of aircraft model, or name

of the aircraft category (e.g. helicopter or gyrocopter) may be used as a prefix to
the callsign.

1.8.3 An aircraft should request the service required on initial contact when freecalling a
ground station.

Westbury Approach, G-ABCD,
request Traffic Service

Wrayton Control, G-ABCD, I wish to
file an airborne flight plan

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1.8.4 An aircraft shall not change its callsign type during a flight. However, where there is
a likelihood that confusion may occur because of similar callsigns, an aircraft may be
instructed by an air traffic service unit (ATSU) to change the type of its callsign
temporarily.

1.8.5 The similarity of some aircraft callsigns on the same frequency can cause confusion
which may lead to an incident. The following are particularly liable to be confused:

a) Callsigns which have in common three or more digits, especially when the flight

numbers are the same, e.g. AIC 515 and SAS 515;
b) Aircraft with similar registrations, e.g. G-ASSB and G-ATSB or HB-SSB.
Controllers are to warn the pilots concerned and, if necessary, instruct one or both

aircraft to use alternative or full callsigns while they remain on the frequency.

1.8.6 Aircraft in the heavy wake turbulence category shall include the word ‘HEAVY’
immediately after the aircraft callsign in the initial call to each ATSU. The purpose of
this call is to confirm the aircraft type and/or wake turbulence category is the same as
that stated on the flight progress strip. For the A380 the word "SUPER" is to be
included after the callsign on initial contact.

1.8.7 On initial contact, student pilots who are flying solo shall use the callsign prefix
‘STUDENT’

1

. Once acknowledged, it will not normally be necessary for student pilots
to use the prefix in subsequent transmissions until making initial contact with other
ATSUs, unless they feel they are being instructed to do something with which they
are unfamiliar.

1.8.8 Controllers will acknowledge the initial call, again using the prefix, and can be
expected, in so far as is 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.

Walden Tower, STUDENT
G-ABCD, on the apron, request taxi
for local VFR flight

Wrayton Information, STUDENT G­ABCD, request Basic Service

STUDENT G-ABCD, Walden Tower,
taxi holding point Alpha, runway 24

STUDENT G-ABCD, Wrayton
Information, pass your message

1.8.9 Flight Instructors must brief students, specifically, on the use of this callsign prefix as
part of their pre-solo briefing. The use of this callsign prefix is not intended to remove
the additional requirement for flight instructors to notify ATSUs separately of ‘first
solo’ flights where this is normal practice.

1.8.10 When receiving an ATS surveillance service, certain ex-military aircraft types have
been granted a CAA exemption from the Air Navigation Order requirement to fly at an
IAS less than 250 kt below Flight Level 100. In order to alert the controller to this
higher speed profile, pilots of exempted aircraft shall, on initial contact, prefix the
aircraft callsign with 'FASTJET' or 'FASTPROP' (depending on propulsion type), e.g.
“Kennington Radar, FASTJET G-ABCD request Deconfliction service”. Use of this
prefix shall be confined to initial contact with ATC agencies for periods of flight during
which operations at airspeeds in excess of 250 kt are intended. Once acknowledged,
it will not normally be necessary for pilots to use the prefix in subsequent
transmissions until making initial contact with other ATSUs.

1. Although intended primarily for use by ab initio students, the prefix shall also be used in other circumstances where, for

example, the holder of a valid licence is returning to flying practice after a significant absence and is undergoing renewal
training involving solo flight conducted as a student under the supervision of a flight instructor.

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1.9 Military Aircraft Callsigns

1.9.1 Aircraft Callsigns
Military aircraft use callsigns derived from 2 systems. Front line aircraft, in the main,

use operational callsigns consisting of a 3 character prefix of numbers and letters
(trigraph) suffixed by a 2 number (dinome) mission identifier. Callsigns for Flying
Training Units (FTUs) and Search and Rescue (SAR) aircraft use fixed ICAO allocated
3 letter designators with figure suffixes as pilot number callsigns. The term FTU
embraces all flying training units (including University Air Squadrons (UASs) and
Gliding Schools (GSs)), Maintenance Units and Air Experience Flights (AEFs), plus the
Operational Conversion Units (OCUs) of HQ AIR who will nominate which OCUs are
not included in the scope of this sub section. The salient features of the 2 systems
are outlined in the following paragraphs.

1.9.2 Mission Number Callsigns
Mission number callsigns are based on a 3 character group of which the last character

is a letter and the first 2 characters are either letter/number or number/letter. They are
valid for a 24 hour period but the system has insufficient capacity to provide entirely
different callsigns for each individual aircraft sortie. Callsigns are configured using a 3
element base callsign root with a 2 number suffix allocated at random by the tasking
agency. If several aircraft in formation make up a single mission, the mission is
allocated a single callsign and each aircraft is given a further identifying letter suffix.
For example T4G (root plus mission), T4G22A, B, C and D (root, mission and 4 aircraft
formation).

1.9.3 Pilot Number Callsigns
The Pilot Number Callsign system is based on a 2 or 3-figure pilot number suffix to a

3-letter callsign root, e.g. VYJ 44 or CWP 186:

• Callsign Root. Each major FTU is allocated one CAA approved fixed 3 letter callsign

root. Four individual trigraphs are allocated to the UASs, one to all AEFs and one to
all GSs.

• Pilot Numbers. Pilot Numbers are allocated as follows:

• Where possible a Pilot Number is allocated to each pilot when posted to an FTU,
and normally is to be retained for the duration of the appointment or course of
instruction.

• For UASs, AEFs and GSs, the respective HQs will allocate blocks of Pilot
Numbers to each element to simplify identification of pilots from different
elements using the same callsign root.

1.9.4 Formation Callsigns
When aircraft are operating as a formation, the use of formation callsigns may be

desirable to facilitate communications both within the formation and by the leader
with ground stations. Formation callsigns should be as detailed in 1.9.2 above, or as
authorised by single Service regulations.

1.9.5 Word Callsigns
If 2 or more aircraft are flying as a formation, the formation may be allocated an

approved word callsign, in addition to the normal mission/pilot numbers allocated to
each aircraft. The mission/pilot numbers will only be used in the event of a split. For
the duration of the formation flight, the aircraft should be identified by adding the
words 'one', '2', etc. to the formation callsign, e.g. Bear one, Bear 2, etc. Where
formations operate using the callsign of the lead aircraft, controllers are to add the
word 'flight' or 'formation' to the callsign, when transmitting instructions relevant to
the whole formation e.g. 'EAGLE 51 FLIGHT'. Where a transmission is relevant to
only one element of the formation, this should be clarified e.g. 'EAGLE 51 ONLY',
climb etc.'.

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Examples of formation callsigns are:
"BLACKCAT" – denotes a UK formation
"BLACKCAT 1" – denotes a UK single element
"DEADLY 31 flight" – denotes a United States Air Force (USAF) formation
"DEADLY 31" – denotes a USAF singleton.

1.9.6 Search and Rescue Callsigns
Callsigns for Search and Rescue are to be as follows:

• Fixed wing aircraft on SAR are to use the special 4 letter W/T callsigns, suffixed by

a 2 figure Mission Number. For voice, the word 'rescue' is used, suffixed by the
Mission Number.

• Helicopters on SAR are to employ the words 'rescue helicopter' suffixed by a

Mission Number. SAR squadron helicopters will use Pilot Number callsigns in
accordance with paragraph 3 when not engaged in SAR tasks using the trigraph
allocated to their base unit.

• SAR callsigns are also listed in the current edition of BAM/25/7.

1.9.7 Transit Flights
In the same way that aircraft of civil airlines have a callsign which identifies the parent

airline, military aircraft making transit (primarily overseas transit) flights requiring a
flight plan to be fed into the civil air traffic system should have a military identifier as
an element of the callsign as detailed in single Service regulations.

1.9.8 Callsign Abbreviation
Once positive contact has been established, and provided no possibility of confusion

exists, callsigns may be abbreviated as follows:

• For transit flights, a military identifier followed by whatever the air traffic controller

specifies once the full callsign has been used to identify the aircraft.

• On military communications the abbreviation should be:

• For Mission Numbers. As only the third element of the trigraph is always a
letter, the abbreviated callsign should be the third element followed by the
dinome.

• For Pilot Numbers. The first element of the callsign root followed by the
dinome or trinome.

However, in all cases the responsibility to shorten lies with ATC as they may be
dealing with many aircraft.

1.10 Continuation of Communications

1.10.1 The placement of the callsigns of both the aircraft and the ground station within an
established RTF exchange should be as follows:

Ground to Air: Aircraft callsign – message or reply.
Air to Ground:
a) Initiation of new information/request etc. – Aircraft callsign then message;

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b) Reply – Repeat of pertinent information/readback/acknowledgement then aircraft

callsign.

G-ABCD, descend FL80

G-ABCD, request descent

Descend FL80, G-ABCD

G-ABCD, maintaining FL80

G-CD

G-CD, descend FL40

Descend FL40, G-CD

1.10.2 When it is considered that reception is likely to be difficult, important elements of the
message should be spoken twice.

1.10.3 When a ground station wishes to broadcast information to all aircraft likely to receive
it, the message should be prefaced by the call 'All stations'.

No reply is expected to such general calls unless individual stations are subsequently
called upon to acknowledge receipt.

All stations Wrayton control, Colinton
VOR on test

1.10.4 If there is doubt that a message has been correctly received, a repetition of the
message shall be requested either in full or in part.

Table 10

Phrase Meaning

Say again Repeat entire message

Say again... (item) Repeat specific item

Say again all before... (the first word satisfactorily
received)

Say again all after... (the last word satisfactorily
received)

Say again... (word before missing portion) to...
(word after missing portion)

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1.10.5 When a station is called but is uncertain of the identification of the calling station, the
calling station should be requested to repeat its callsign until identification is
established.

Stourton Ground, BIGJET 347

Station calling Stourton Ground say
again your callsign

1.11 Corrections and Repetitions

1.11.1 When an error is made in a transmission the word 'CORRECTION' shall be spoken,
the last correct group or phrase repeated and then the correct version transmitted.

BIGJET 347, Wicken 47
FL280 Marlow 07
correction Marlow 57

BIGJET 347, Roger

1.11.2 If a correction can best be made by repeating the entire message, the operator shall
use the phrase 'CORRECTION I SAY AGAIN' before transmitting the message a
second time.

1.12 Acknowledgement of Receipt
Acknowledgements of information should be signified by the use of the receiving

stations’ callsign or Roger callsign, and not by messages such as: 'callsign-copy the
weather' or 'callsign-copy the traffic'.

1.13 Transfer of Communications

1.13.1 To transfer communications with an aircraft to another unit, controllers shall pass
instructions giving:

a) the identity of the unit to be contacted;
b) the frequency to be used for contact.
Transfer of communication instructions should be passed in a single message. Items

which require a read-back should normally be passed in a separate transmission
before transfer.

1.13.2 If no further communication is received from the pilot after an acknowledgement,
satisfactory transfer of communication may be assumed.

1.13.3 An aircraft will normally be advised by the appropriate aeronautical station to change
from one radio frequency to another in accordance with agreed procedures.

BIGJET 347, contact Wrayton
Control 129.125

Wrayton Control 129.125,
BIGJET 347

In the absence of such advice, the aircraft shall notify the aeronautical station
before such a change takes place. Aircraft flying in controlled airspace must obtain

permission from the controlling authority before changing frequency.

1.13.4 An aircraft may be instructed to ‘standby’ on a frequency when it is intended that the
ATSU will initiate communications, and to monitor a frequency on which information
is being broadcast.

BIGJET 347, standby for Kennington
Towe r 118 . 95 0

Standby for Kennington Tower

118.950, BIGJET 347

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BIGJET 347, monitor ATIS 128.275

Monitor ATIS 128.275,
BIGJET 347

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1.13.5 The controller may instruct the pilot to contact another agency on passing a specific
point or when passing, leaving or reaching a specified level.

G-CD, at Littletown contact Borton
Approach 122.375

BIGJET 347, when passing FL120
contact Wrayton Control 119.725

At Littletown contact Borton
Approach 122.375, G-CD

When passing FL120 contact
Wrayton Control 119.725, BIGJET
347

1.13.6 Where the aircraft is transferred to another agency whilst on a radar heading, the
controller will instruct the pilot to report the radar heading to the next agency.

BIGJET 347, report radar heading to
Wrayton Control, 116.335

1.13.7 If the airspace does not dictate that an aircraft must remain in contact with a specific
ATSU and the pilot wishes to freecall another agency he should request, or notify
such an intention.

Westbury, G-ABCD, request change
to Wrayton Information 125.750

Wrayton Information, G-ABCD,
changing to Wrayton Centre 121.5
for Practice Pan

1.14 Clearance Issue and Read-back Requirements

1.14.1 Provisions governing clearances are contained in the PANS-ATM (ICAO Doc 4444). A
clearance may vary in content from a detailed description of the route and levels to
be flown to a brief standard instrument departure (SID) according to local procedures.

1.14.2 Controllers will pass a clearance slowly and clearly since the pilot needs to write it
down; wasteful repetition will thus be avoided. Whenever possible, a route clearance
should be passed to an aircraft before start up and the aircraft’s full callsign will always
be used. A route clearance and local departure instructions shall not be passed in the
same transmission. When a route clearance is passed subsequent to local departure
instructions, or to an aircraft that is already airborne, tactical restrictions that remain
in place shall be reiterated to ensure that the immediate profile to be flown by the pilot
is unambiguous. Generally, controllers will avoid passing a clearance to a pilot

engaged in complicated taxiing manoeuvres and on no occasion when the pilot
is engaged in line up or take-off manoeuvres.

1.14.3 An ATC route clearance is NOT an instruction to take-off or enter an active runway.
The words 'TAKE-OFF' are used only when an aircraft is cleared for take-off. At
all other times the word 'DEPARTURE' is used.

1.14.4 The stringency of the read back requirement is directly related to the possible
seriousness of a misunderstanding in the transmission and receipt of ATC clearance
and instructions. ATC route clearances shall always be read back unless
otherwise authorised by the appropriate ATS authority in which case they shall
be acknowledged in a positive manner. Read backs shall always include the aircraft
callsign.

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BIGJET 347, cleared to Kennington
via A1, at FL60, squawk 5501

BIGJET 347, cleared to Kennington
via A1, Wicken 3 Delta departure,
squawk 5501

G-ABCD, after departure cleared to
zone boundary via route Echo. Climb
to altitude 2000 feet QNH 1008,
squawk 6522

Cleared to Kennington via A1, at
FL60, squawk 5501, BIGJET 347

BIGJET 347, correct

Cleared to Kennington via A1,
Wicken 3 Delta departure, squawk
5501, BIGJET 347

BIGJET 347, correct

After departure cleared to zone
boundary via route Echo. Climb to
altitude 2000 feet QNH 1008,
squawk 6522, G-ABCD

G-CD, correct

1.14.5 The ATS messages listed below are to be read back in full by the pilot/driver. If a
readback is not received the pilot/driver will be asked to do so. Similarly, the pilot/
driver is expected to request that instructions are repeated or clarified if any are not
fully understood.

Taxi/Towing Instructions
Level Instructions
Heading Instructions
Speed Instructions
Airways or Route Clearances
Approach Clearances
Runway-in-Use
Clearance to Enter, Land On, Take-Off On, Backtrack, Cross, or Hold Short of

any Active Runway
SSR Operating Instructions
Altimeter Settings, including units when value is below 1000 hectopascals
VDF Information
Frequency Changes

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Type of ATS Service
Transition Levels

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G-ABCD, cleared to cross A1 at
Wicken, maintain FL70 whilst in
controlled airspace. Report entering
the airway

G-CD, hold position

G-CD, contact Ground 118.050

BIGJET 347, Squawk 6402

Cleared to cross A1 at Wicken,
maintain FL70 in controlled
airspace, Wilco, G-ABCD

Holding, G-CD

Ground on 118.050, G-CD

6402, BIGJET 347

1.14.6 Items which do not appear in the above list may be acknowledged with an
abbreviated read back.

1.14.7 If an aircraft read back of a clearance or instruction is incorrect, the controller shall
transmit the word 'NEGATIVE' followed by the correct version.

G-CD, QNH 1003

QNH 1013, G-CD

G-CD, Negative, QNH 1003

QNH 1003, G-CD

1.14.8 If at any time a pilot receives a clearance or instruction with which he cannot comply,
he should advise the controller using the phrase 'UNABLE' (COMPLY) and give the
reason(s).

BIGJET 347, Wrayton climb FL280,
cross Wicken FL150 or above

Wrayton, BIGJET 347, unable cross
Wicken FL150 due weight

1.14.9 When an amendment is made to a clearance the new clearance shall be read in full
to the pilot and shall automatically cancel any previous clearance. Controllers must be
aware, therefore, that if the original clearance included a restriction, e.g. “cross KTN
FL150 or below” then the issue of a revised clearance automatically cancels the
earlier restriction, unless it is reiterated with the revised clearance.

1.14.10 When any doubt exists as to whether a message containing critical information has
been passed by the controller or received and understood by the pilot, the message
must be repeated. Critical information is information, other than that required to
enable routine flight, which must be received by pilots to ensure the safety and
effective operation of their aircraft.

The following can be considered as examples of critical information:

• Low Visibility Procedures

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• Windshear Warnings

• Essential Aerodrome Information

• Equipment serviceability (i.e. ILS/navigational aids)

• Weather hazards (thunderstorms, hail, icing, etc.)

1.15 Withholding Clearances

1.15.1 It may be considered expedient by Government to withhold an ATC clearance to
aircraft, particularly if the aircraft has not entered UK national airspace. When
authorised, the following phraseology is to be used.

BIGJET 347, I am instructed by Her
Majesty's Government to refuse
entry into United Kingdom airspace.
What are your intentions?

BIGJET 347, I am instructed by Her
Majesty's Government to inform
you that landing clearance has been
refused for any airfield within the
United Kingdom. What are your
intentions?

BIGJET 347, I am instructed by Her
Majesty's Government that you are
to hold at KTN at FL270.
Acknowledge

1.15.2 The Aerodrome Authority and certain other persons are empowered to prohibit flight
and they may instruct a controller to withhold a clearance. If a controller has not been
instructed to withhold clearance but has reason to believe that a planned flight is liable
to endanger life or involve a breach of legislation, the controller is to warn the pilot of
the hazardous condition or apparent infringement and obtain an acknowledgement of
the message. The hazardous condition may be reported by an outside agency or
observed by the controller. Because of possible legal action when pilots disregard the
warnings described above, it is essential that clear and precise messages are passed
to the pilots concerned and acknowledgements obtained. Further transmissions may
be necessary to ascertain the intentions of the pilot.

BIGJET 347, I am informed that
there may be damage to the port
wing tip of your aircraft. It appears
that your planned flight is liable to
endanger life. Acknowledge

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G-ABCD, you are advised surface
wind 280 degrees 37 knots gusting

50. It appears that your planned
flight is liable to endanger life.
Acknowledge

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1.15.3 In the case of an anticipated infringement of legislation the controller is to warn the
pilot that if he does take-off the facts will be reported to the appropriate authority.

G-ABCD, your planned flight appears
to contravene legislation because
the required minima for VFR flight
are not present. If you take off I shall
be required to report the facts.
Acknowledge

1.16 Simultaneous Transmissions

1.16.1 Direct communications between pilots and ATSUs can be adversely affected by
simultaneous transmissions which, effectively, block all or part of intended
messages. Moreover, whilst the situation may be apparent to the controller or
another pilot, the individuals who inadvertently make such transmissions may be
unaware. On hearing a simultaneous transmission it can be helpful for the controller
(or another pilot if it is the controller’s transmission which has been blocked) to draw
attention to the situation using the word ‘blocked’.

1.16.1.1 Controller Example (where pilots have transmitted simultaneously):

Transmission Blocked – (callsign if
known) say again

1.16.1.2 Pilot Example (where another pilot has blocked a controller’s transmission):

Transmission Blocked – Wrayton say
again, BIGJET 345

1.17 Complying with Clearances and Instructions

1.17.1 Pilots are expected to comply with clearances and instructions promptly,
commensurate with normal aircraft operations. If, for any reason, a pilot does not
wish to comply with an instruction promptly, the pilot should advise the ATS unit and
give an indication of when he intends to comply.

1.17.2 If an ATS unit wishes to indicate that time of compliance is at the pilot's discretion,
the ATS message will include the phrase 'when ready'.

1.17.3 If an ATS unit wishes to indicate that the clearance or instruction is required to be
complied with at a particular point in the flight, the message will include the phrase
'after passing'.

1.17.4 If an ATS unit wishes to indicate that the instruction or clearance must be complied
with at once, the controller's message will include the word 'now' or 'immediately'.
Use of the word 'now' indicates that the instruction should be complied with in
accordance with normal aircraft operating procedures, but without delay. Use of the
word 'immediately' indicates a further degree of urgency exists (e.g. to avoid flight
into terrain or restricted airspace, or for the provision of collision avoidance, see
Chapter 5 Paragraph 1.6.4 Avoiding Action Phraseology). In such circumstances, the
pilot should take action to comply with the instruction as soon as practicable, subject
to the safety of the aircraft.

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1.17.5 In order to ensure any restriction is not blocked by a pilot acknowledgement, the
phrase or word, indicating when a clearance or instruction should be complied with,
will normally be placed before the executive instruction (Paragraph 1.17.6, 1st and
2nd examples), but in certain cases the phrase or word may be placed between the
instruction and the value of the instruction (Paragraph 1.17.6, 3rd and 4th examples).

1.17.6 The phrases and words described in this section are most commonly used in
association with level instructions (see also Chapter 3, Level Reporting, Paragraph

1.2), but may be used in other circumstances if appropriate. Examples are shown
below:

BIGJET 347, after passing North
Cross, descend FL80

After passing North Cross,
descend FL80, BIGJET 347

BIGJET 347, when ready descend
FL170, Report leaving FL210

BIGJET 347, reduce speed now
210 kt

BIGJET 347, climb immediately
FL35

1.18 Communication Failure

1.18.1 Air – Ground
a) Check the following points:

i) The correct frequency has been selected for the route being flown.
ii) The Aeronautical Station being called is open for watch.
iii) The aircraft is not out of radio range.
iv) Receiver volume correctly set.

b) If the previous points are in order it may be that the aircraft equipment is not

functioning correctly. Complete the checks of headset and radio installation
appropriate to the aircraft.

When ready descend FL170. Report
leaving FL210, BIGJET 347

Reducing speed now 210 kt,
BIGJET 347

Climbing immediately FL35,
BIGJET 347

c) When an aircraft station is unable to establish contact with the aeronautical station

d) The pilot may still be unable to establish communication on any designated

e) Where a transmitter failure is suspected, check or change the microphone. Listen

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on the designated frequency it shall attempt to establish contact on another
frequency appropriate to the route being flown. If this attempt fails, the aircraft
station shall attempt to establish communication with other aircraft or other
aeronautical stations on frequencies appropriate to the route.

aeronautical station frequency, or with any other aircraft. The pilot is then to
transmit his message twice on the designated frequency, including the addressee
for whom the message is intended, preceded by the phrase 'TRANSMITTING
BLIND' in case the transmitter is still functioning.

out on the designated frequency for instructions. It should be possible to answer
questions by use of the carrier wave if the microphone is not functioning (see
Chapter 8 paragraph 1.7.1).

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f) In the case of a receiver failure transmit reports twice at the scheduled times or

positions on the designated frequency preceded by the phrase 'TRANSMITTING
BLIND DUE TO RECEIVER FAILURE'.

g) An aircraft which is being provided with air traffic control service, advisory service

or aerodrome flight information service is to transmit information regarding the
intention of the pilot in command with respect to the continuation of the flight.
Specific procedures for the action to be taken by pilots of IFR and Special VFR
flights are contained in the appropriate AIP ENR and/or AD sections.

1.18.2 Ground – Air

1.18.2.1 After completing checks of ground equipment (most airports have standby and
emergency communications equipment) the ground station will request other
aeronautical stations and aircraft to attempt to communicate with the aircraft which
has failed to maintain contact.

1.18.2.2 If still unable to establish communication the aeronautical station will transmit
messages addressed to the aircraft by blind transmission on the frequency on which
the aircraft is believed to be listening.

1.18.2.3 These will consist of:
a) The level, route and EAT (or ETA) to which it is assumed the aircraft is adhering.
b) The weather conditions at the destination aerodrome and suitable alternate and, if

practicable, the weather conditions in an area or areas suitable for descent through
cloud procedure to be effected. (See AIP ENR Section.)

1.19 Test Transmissions

1.19.1 All radio transmissions for test purposes shall be of the minimum duration necessary
for the test and shall not continue for more than 10 seconds. The recurrence of such
transmissions shall be kept to the minimum necessary for the test.

1.19.2 The nature of the test shall be such that it is identifiable as a test transmission and
cannot be confused with other communications. To achieve this the following format
shall be used:

• the callsign of the aeronautical station being called;

• 'the aircraft identification';

• the words 'RADIO CHECK';

• 'the frequency' being used;

1.19.3 The operator of the aeronautical radio station being called will assess the transmission
and will advise the aircraft making the test transmission in terms of the readability
scale (Table 11), together with a comment on the nature of any abnormality noted (i.e.
excessive noise) using the following format:

• 'the aircraft identification';

• 'the callsign' of the aeronautical station replying;

• 'READABILITY x' (where 'x' is a number taken from Table 11);

• 'additional information' with respect to any noted abnormality;
NOTE: For practical reasons it may be necessary for the operator of an aeronautical

31 March 2011

station to reply with 'STATION CALLING (frequency or 8.33 channel)
UNREADABLE'.

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Table 11

Readability Scale Meaning

1 Unreadable
2 Readable now and then
3 Readable but with difficulty
4 Readable
5 Perfectly readable

Borton Tower, G-ABCD, radio check

118.725

G-ABCD, Borton Tower, readability 5

or,

G-CD, Borton Tower, readability 3 with
a loud background whistle

or,

Station calling Borton Tower
readability 1

1.20 Pilot Complaints Concerning Aeronautical Telecommunications
Pilots should report faults concerning services and facilities in the Aeronautical

Mobile Broadcast and Navigation Services to the Briefing Officer, Senior
Telecommunications Officer or Senior Controller at the destination or airport of first
landing in order that remedial action can be taken. Reports of local unserviceabilities
will be forwarded to the Telecommunications staff if received on RTF by the ATSU.

1.21 Air Traffic Service Complaints Concerning Aircraft Communications
Aircraft radio faults including technical failure, incorrect operating procedures and

misuse of specific radio channels may result in the aircraft operator receiving a
communication from the CAA detailing the fault condition inviting the operator to
explain and/or state what corrective action has been taken.

1.22 Hours of Service and Communications Watch

1.22.1 The hours of service of the radio facilities available in the United Kingdom are
published in the UK AIP (ENR and AD) which also details those periods set aside for
maintenance.

1.22.2 Aircraft stations shall, if possible, communicate directly with the ATSU appropriate to
the area in which the aircraft are flying. If unable to do so, aircraft stations shall use
any relay means available and appropriate to transmit messages to the ATSU.

1.22.3 When normal communications from an aeronautical station to an aircraft station
cannot be established, the aeronautical station shall use any relay means available and
appropriate to transmit messages to the aircraft station.

1.22.4 When an aircraft has established communication with an ATSU it is required to
maintain a listening watch with that ATSU and advise the ATSU when the listening
watch is about to cease. Aircraft should not cease to maintain a listening watch,
except for reasons of safety, without informing the ATSU concerned. A time at which
it is expected that the watch will be resumed must be stated.

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1.23 Record of Communications
All ATC units have automatic equipment to record air-ground communications and

some other ATS units (e.g. AFIS) also have such equipment.

1.24 Categories of Message
The categories of messages handled by the aeronautical mobile service are in the

following order of priority:

a) Distress messages

b) Urgency messages

See Chapter 8 – Emergency Phraseology

}

c) Communications relating

to direction finding

d) Flight safety messages See Chapter 9 paragraph 1.6

e) Meteorological messages See Chapter 4 paragraph 7

f) Flight Regularity messages See Chapter 9 paragraph 1.6.

See Chapter 6 paragraph 1.7

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Chapter 3 General Phraseology

1 General

1.1 Introduction

1.1.1 The phraseology detailed in this manual has been established for the purpose of
ensuring uniformity in RTF communications. Communications shall be concise and
unambiguous, using standard phraseology for all situations for which it is specified.
Obviously, it is not practicable to detail phraseology examples suitable for every
situation. However, if standard phrases are adhered to when composing a message,
any possible ambiguity will be reduced to a minimum. Only when standard
phraseology cannot serve an intended transmission, shall plain language be used.

1.1.2 Some abbreviations, which by their common usage have become part of aviation
terminology, may be spoken using their constituent letters rather than the spelling
alphabet, for example, ILS, QNH, RVR, etc., (see Chapter 1, paragraph 1.2).

1.1.3 For all transmissions, with the exception of those used for surveillance radar
approaches or precision radar approaches, the word 'degrees' shall be appended to
heading figures where the heading ends in zero, or in cases where confusion or
ambiguity may result.

1.1.4 For all transmissions, the word 'hectopascal' shall be appended to figures when
transmitting a pressure setting below 1000 hPa, or in cases where confusion or
ambiguity may result.

1.1.5 The following words may be omitted from transmissions provided that no confusion
or ambiguity may result:

a) 'Surface' and 'knots' in relation to surface wind direction and speed.
b) 'Degrees' in relation to surface wind direction.
c) 'Visibility', 'cloud' and 'height' in meteorological reports.
d) 'over', 'Roger' and 'out'.

1.1.6 The excessive use of courtesies should be avoided.

1.2 Level Reporting

1.2.1 Only basic level instructions are detailed in this Chapter. More comprehensive
phrases are contained in subsequent Chapters in the context in which they are most
commonly used.

1.2.2 The precise phraseology used in the transmission and acknowledgement of climb and
descent clearances will vary, depending upon the circumstances, traffic density and
nature of the flight operations.

1.2.3 However, care must be taken to ensure that misunderstandings are not generated as
a consequence of the phraseology employed during these phases of flight. For
example, levels may be reported as altitude, height or flight levels according to the
phase of flight and the altimeter setting. Therefore, when passing level messages,
the following conventions apply:

a) The word 'to' is to be omitted from messages relating to FLIGHT LEVELS.
b) All messages relating to an aircraft’s climb or descent to a HEIGHT or ALTITUDE

employ the word 'to' followed immediately by the word HEIGHT or ALTITUDE.
Furthermore, the initial message in any such RTF exchange will also include the
appropriate QFE or QNH.

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c) The phrase 're-cleared' should not be employed.
d) When transmitting messages containing flight levels each digit shall be

transmitted separately. However, in an endeavour to reduce ‘level busts’ caused
by the confusion between some levels (100/110, 200/220 etc.), levels which are
whole hundreds e.g. FL100, 200, 300 shall be spoken as “Flight level (number)
HUN DRED”. The word hundred must not be used for headings.

G-CD, report your level

G-CD, report your level

G-CD, maintaining FL65

G-CD, descend FL45

Descend FL45, G-CD

G-CD, maintaining altitude 2500 feet
Wessex 998 hectopascals

G-CD, descend to altitude 2000 feet
Borton QNH 1000

Descend to altitude 2000 feet
Borton QNH 1000, G-CD

G-CD, descend to altitude 1500 feet

Descend to altitude 1500 feet, G-CD

G-CD, descend to height 1000 feet
QFE 997 hectopascals

Descend to height 1000 feet QFE
997 hectopascals, G-CD

NOTES: 1 Use of the word 'hectopascal' for pressures lower than 1000

2 Transmission of Regional Pressure Setting (Wessex) limited to regional name

and pressure.

1.2.3.1 In the following examples the operations of climbing and descending are
interchangeable and examples of only one form are given.

G-CD, report passing FL80 Wilco, G-CD

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G-CD, passing FL80

G-CD, maintain altitude 2500 feet Maintaining altitude 2500 feet,

G-CD

G-CD, climb FL70 Climb FL70, G-CD

G-CD, reaching FL70

G-CD, request descent G-CD, descend FL60

Descend FL60, G-CD

G-CD, not below FL60

BIGJET 347, after passing North
Cross descend FL80

BIGJET 347 stop descent at FL210 Stop descent at FL210 BIGJET 347

BIGJET 347, descend FL150,
level by South Cross

BIGJET 347, climb FL290,
level at time 55

Not below FL60, G-CD

After passing North Cross descend
FL80, BIGJET 347

Descend FL150 level by South
Cross, BIGJET 347

Climb FL290, level at time 55,
BIGJET 347

1.2.3.2 Where the controller requires the aircraft to achieve a specific rate of climb or descent,
the controller shall use the phraseology shown below.

BIGJET 347, climb at 1000 feet per
minute or greater

Climb at 1000 feet per minute or
greater, BIGJET 347

BIGJET 347, descend at 500 feet per
minute or less

Descend at 500 feet per minute or
less, BIGJET 347

1.2.3.3 Exceptionally, a best rate of climb or descent may be required. Pilots of aircraft
operating within controlled airspace in the London and Scottish FIRs have been
instructed not to operate with a climb or descent rate in excess of 8000 ft/min. Aircraft
in an emergency and certain military activities are exempt from this restriction.

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BIGJET 347, expedite descent FL180 Expedite descent FL180,

BIGJET 347

BIGJET 347, climb FL280 expedite
until passing FL180

Climb FL280 expedite until passing
FL180, BIGJET 347

or,

BIGJET 347, unable expedite climb
due weight

1.2.3.4 Under exceptional circumstances, if instant descent/climb is required, the word
‘immediately’ shall be used.

BIGJET 347, descend immediately
FL200 due traffic

Descend immediately FL200,
BIGJET 347

1.2.3.5 Pilots are expected to comply with ATC instructions as soon as they are issued.
However, when a climb/descent is left to the discretion of the pilot, the words ‘when
ready’ shall be used.

1.2.3.6 Except as described in paragraph 1.4, a pilot receiving a Radar Control Service is not
required to report leaving a level, passing a level, or reaching a level, unless
specifically requested to do so.

BIGJET 347, when ready climb
FL280, report leaving FL200

When ready climb FL280, wilco,
BIGJET 347

BIGJET 347, leaving FL200 climbing
FL280

BIGJET 347, Roger

1.2.4 When pilots are instructed to report leaving a level, they should advise ATC that they
have left an assigned level only when the aircraft’s altimeter indicates that the aircraft
has actually departed from that level and is maintaining a positive rate of climb or
descent, in accordance with published procedures.

1.2.5 To avoid excessive delays to traffic when ATS surveillance systems are not available,
controllers may authorise an aircraft to climb or descend in VMC, subject to a number
of safeguards, including the pilot agreeing to maintain his own separation from other
aircraft.

BIGJET 347, maintaining own
separation and VMC descend FL50

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1.3 Speed Control

1.3.1 Controllers may instruct pilots to increase/decrease speed in order to maintain the
appropriate separation.

BIGJET 347, reduce speed to Mach
0·7

BIGJET 347, maintain present speed

BIGJET 347, maintain 250 knots or
greater

BIGJET 347, not above 250 knots

BIGJET 347, reduce to minimum
clean speed

BIGJET 347, reduce to minimum
approach speed

BIGJET 347, maintain 160 knots
until 4 miles final

Reduce speed to Mach 0·7, BIGJET
347

Maintain present speed, BIGJET 347

Maintain 250 knots or greater, BIGJET
347

Not above 250 knots, BIGJET 347

Reduce to minimum clean speed,
BIGJET 347

Reduce to minimum approach speed,
BIGJET 347

Maintain 160 knots until 4 miles final,
BIGJET 347

BIGJET 347, maintain 160 knots
until outer marker

Maintain 160 knots until outer marker,
BIGJET 347

1.3.2 The following phraseology shall be used by controllers when providing speed control
to aircraft at or above FL280 that have been cleared to levels below FL280.

1.3.2.1 Where the controller only requires speed control to apply following the point at which
the aircraft changes over from Mach number to IAS, the phraseology to be used by
the controller is:

BIGJET 347, descend FL120, on
speed conversion, 250 knots

Descend FL120, on speed conversion,
250 knots, BIGJET 347

1.3.2.2 Where the controller requires the aircraft to fly at a specific Mach number until the
changeover to IAS and then fly a specified IAS, the phraseology to be used by the
controller is:

BIGJET 347, Mach ·78, on speed
conversion, 250 knots

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1.3.2.3 Where the controller requires the aircraft to fly the specified IAS as soon as
practicable, the phraseology to be used by the controller is:

BIGJET 347, when able, speed 250
knots

1.3.2.4 The procedures above may be used in reverse for the application of speed control to
aircraft currently below FL280 but climbing to a level above FL280.

BIGJET 347, on speed conversion,
Mach ·7

BIGJET 347, 250 knots, on speed
conversion, Mach ·7

BIGJET 347, maintaining own
separation and VMC descend FL50

1.4 Initial Call – IFR flights

1.4.1 Format of Initial Calls
Pilots of aircraft flying Instrument Departures (including those outside controlled

airspace) shall include the following information on initial contact with the first en­route ATS Unit (see also Chapter 6 Approach Phraseology Paragraph 1.1.2):

a) Callsign;
b) SID or Standard Departure Route Designator (where appropriate);
c) Current or passing level; PLUS
d) Initial climb level (i.e. the first level at which the aircraft will level off unless

otherwise cleared. For example, on a Standard Instrument Departure that involves
a stepped climb profile, the initial climb level will be the first level specified in the
profile).

Westbury Departure, BIGJET 347,
BIGRO 5D, Passing Altitude 2300
feet climbing FL80

1.4.2 Subsequent Frequency Changes
Unless otherwise instructed or paragraph 1.4.1 applies, when changing

communication channel to an ATC unit (including changes within the same ATS unit),
the initial call on the new channel shall include aircraft identification and level only.

BIGJET 347, Westbury, Roger

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Westbury Control, BIGJET 347,
FL 350

BIGJET 347, Westbury, Roger

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1.4.3 Level information should be included in the report as follows:
a) if the aircraft is in level flight but cleared to another level, the call shall include the

aircraft identification followed by the current level and the cleared level;

Westbury Approach, BIGJET 347,
Maintaining FL350 cleared FL250

BIGJET 347, Westbury, Roger

b) if the aircraft is not in level flight, the call shall include the aircraft identification

followed by cleared level only;

Westbury Approach, BIGJET 347,
descending FL90

if

BIGJET 347, Westbury, Roger

c) if the aircraft has been assigned a speed or a heading, the initial call shall also

include the assigned speed or heading.

Westbury Control, BIGJET 347,
FL 90, Maintaining 250 kt

BIGJET 347, Westbury, Roger

1.5 Initial Call – VFR Flight

1.5.1 Normally, the initial call to an ATS unit should only include the minimum information
needed to establish:

a) the service that an enroute flight requires; or
b) the clearance/information that a joining or departing flight requires.

Westbury Approach, G-ABCD,
Request (type of service)

Westbury Tower, G-ABCD, Request
join

Westbury Tower, G-ABCD, Request
taxi for departure to Borton

Westbury Tower, G-ABCD, Request
taxi for the south side maintenance
area

Westbury Tower, G-ABCD, Request
zone transit

The ATS unit will then respond with their callsign and 'Pass Your Message' (optional).

1.6 Passing Message Details

1.6.1 Flights on or in the vicinity of an aerodrome
Pilots of aircraft inbound or outbound to an aerodrome, or wishing to manoeuvre on

an aerodrome, when instructed to pass their message details, should respond in the
manner described in Chapter 4.

1.6.2 En-route flights
Generally, the format of this call is applicable to aircraft operating under Visual Flight

Rules (VFR). However, aircraft operating under Instrument Flight Rules (IFR), when
contacting an ATS unit that does not hold details of the flight, may use the format
described in Paragraph 1.6.3.

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1.6.3 When instructed by the ATS Unit to pass your message details, the reply should
contain the following information, whenever possible in the order specified:

a) Aircraft Callsign / Type

b) Departure Point and Destination

c) Present Position

d) Level
e) Additional details / Intention (e.g. Flight Rules, Next route point)

Reply Example 1:

Westbury Approach, G-ABCD,
request Basic Service

G-ABCD, Cessna 172, from Borton
to Walden, 15NM South of
Westbury, altitude 2500 feet
Wessex 1008, VFR, tracking to
Wells

Basic Service, Wilco, G-CD

G-ABCD, Westbury Approach

G-CD Roger, Basic Service, Report
Wells

Reply Example 2: An aircraft returning to the aerodrome of departure.

Westbury Approach, G-ABCD,
request Basic Service

G-ABCD, PA28 local flight from
Borton, Wells altitude 3500 feet
Wessex 1008, VFR, tracking to
Salisbury

G-ABCD, Westbury Approach, pass
your message

G-CD Roger, Basic Service, traffic is a
Cessna 172, 15NM South of Westbury,
VFR, tracking to Wells at 2500 feet,
Report Salisbury

Wilco, G-CD

1.7 Position Reporting

1.7.1 Position reports shall contain the following elements of information:
a) Aircraft identification

b) Position
c) Time
d) Level
e) Next position and ETA

BIGJET 347, Wicken 47 FL280
Marlow 57

G-ABCD, Wrayton Information report
mid-channel

BIGJET 347

Wilco, G-ABCD

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G-ABCD, mid-channel 25
Altitude 3500
Greenpoint 40

G-ABCD

1.7.2 Where adequate flight progress data is available from other sources, such as ground
radar, aircraft may be exempted from the requirement to make compulsory position
reports.

BIGJET 347, next report at Colinton

BIGJET 347, omit position reports

BIGJET 347, omit position reports
this frequency

BIGJET 347, resume position
reporting

Wilco, BIGJET 347

Wilco, BIGJET 347

Wilco, BIGJET 347

Wilco, BIGJET 347

1.8 Flight Plans

1.8.1 A pilot may file a flight plan with an ATSU during flight, although the use of busy RTF
channels should be avoided; normally the FIS frequency should be used.

Wrayton Control, G-ABCD, I wish to
file an airborne flight plan

G-ABCD, Wrayton Control, pass
your message

1.8.2 The format for an airborne flight plan is as follows:
a) Aircraft identification and type.
b) Position and heading.
c) Level and flight conditions.
d) Departure aerodrome.
e) Estimated time at entry point.
f) Route and point of first intended landing.
g) True airspeed.
h) Desired level on airway or advisory route.

1.8.3 Where the aircraft pilot is responsible for activating a flight plan, this may be done by
asking an ATSU by radio to activate the flight plan.

31 March 2011

G-CD, departed Seton at 38
request activate flight plan

G-CD, departure time 38 will
activate flight plan

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1.8.4 During a flight a pilot may elect to cancel an IFR flight plan.

Wrayton Control, G-CD, cancelling
my IFR flight

G-CD, Roger, IFR flight cancelled at
47

1.8.5 When a pilot has expressed his intention to cancel an IFR flight plan, the ATSU will
pass the pilot any available meteorological information which makes it likely that flight
in VMC cannot be maintained.

G-CD, IMC reported in the vicinity
of Kennington

G-CD, Roger, remaining IFR

1.9 Low Visibility Procedures

1.9.1 Aerodromes that wish to continue operating in poor visibility or are available for
instrument approaches in conditions of low cloud are required to develop and
maintain Low Visibility Procedures (LVP). Controllers shall advise pilots of the
implementation and subsequent cancellation of LVP at an aerodrome.

BIGJET 347, LVPs in force

All stations, LVPs cancelled

Roger, BIGJET 347

1.10 Delays

1.10.1 Where an aircraft is required to hold before making an approach the expected delay
shall be passed to the pilot.

BIGJET 347, delay less than 10
minutes. Expect two holding
patterns

1.10.2 Expected Approach Time (EAT) is the time that Approach Control estimate that an
aircraft will be able to leave the holding facility, following a delay, to commence its
approach to land.

BIGJET 347, expect approach
clearance at 44

1.10.3 If for reasons other than weather, e.g. an obstruction on the runway, the extent of the
delay is not known, aircraft are to be advised "delay not determined" followed by the
reason for the delay.

BIGJET 347, delay not determined,
runway obstructed

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1.10.4 If aircraft elect to hold for the weather to improve at the landing aerodrome, the
controller shall inform the first aircraft entering the holding pattern that "no traffic
delay expected". Subsequent aircraft will be passed "delay not determined" followed
by an indication of the number of aircraft holding.

BIGJET 347, no traffic delay
expected

BiGJET 347, delay not determined 2
aircraft holding for weather
improvement

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Chapter 4 Aerodrome Phraseology

1 Aerodrome Control Service Phraseology

1.1 Introduction

1.1.1 Concise and unambiguous phraseology used at the correct time is vital to the smooth,
safe and expeditious running of an aerodrome and associated ATZ. It is not only the
means by which instructions and information are passed but it also assists pilots in
maintaining an awareness of other traffic in their vicinity, particularly in poor visibility
conditions.

1.1.2 Messages will not be transmitted to an aircraft during take-off, the last part of final
approach or the landing roll, unless it is necessary for safety reasons, because it will
be distracting to the pilot at a time when the cockpit workload is often at its highest.

1.1.3 Local procedures vary from aerodrome to aerodrome and it is impossible to give
examples to cover every situation which may arise at the multiplicity of different types
of aerodrome. Information in addition to that shown in the examples, e.g. time
checks, etc. may be provided as necessary.

1.2 Type of Service

1.2.1 As described in Chapter 2 the type of service provided at an aerodrome falls into one
of three categories. In this section the examples are confined to those used by air
traffic controllers.

1.2.2 Whilst the RTF procedures used by air traffic controllers form the main content of this
publication, it should be noted that the phraseology used by FISOs and Air/Ground
Communication Service operators is different from that used by controllers.
Examples of phraseology for Flight Information Service Officers and Air/Ground
Communication Service operators may be found in Chapter 4 sections 2 and 5
respectively.

1.3 Departure Information and Engine Starting Procedures

1.3.1 Where no ATIS is provided the pilot may ask for current aerodrome information before
requesting start up.

Stourton Ground, BIGJET 347,
request departure information

BIGJET 347, Stourton Ground,
departure runway 32 wind 290 4,
QNH 1008, temperature -2,
dewpoint -3, RVR 550 550 600
metres

Runway 32, QNH 1008, will call for
start up, BIGJET 347

1.3.2 Requests to start engines are normally made to facilitate ATC planning and to avoid
excessive fuel wastage by aircraft delayed on the ground. At certain aerodromes,
along with the request, the pilot will state the location of the aircraft and acknowledge
receipt of the departure ATIS broadcast identifying letter together with the QNH.

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Stourton Ground, BIGJET 347,
stand 24 information Bravo, QNH
1022 request start up

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BIGJET 347, Stourton Ground, start
up at time 35

CAP 413 Radiotelephony Manual

1.3.3 When there will be a delay to the departure of the aircraft the controller will normally
indicate a time to start up or expect to start up.

Stourton Ground, BIGJET 347,
information Charlie QNH 1022,
request start up

1.4 Pushback and Powerback
At many aerodromes at which large aircraft operate, the aircraft are parked nose-in to

the terminal in order to save parking space. Aircraft have to be pushed backwards by
tugs before they can taxi for departure. Some aircraft also have the capability to
reverse from a nose-in position to the terminal under their own power. This procedure
is known as powerback. Requests for pushback or powerback are made to ATC
depending on the local procedures.

BIGJET 347, Stourton Ground, start
up approved

or,

BIGJET 347, Stourton Ground, expect
start up at time 35

or,

BIGJET 347, Stourton Ground, expect
departure at time 49 start up at own
discretion

BIGJET 347, stand 27 request
pushback/powerback

BIGJET 347, pushback/powerback
approved

or,

BIGJET 347, negative. Expect one
minute delay due B747 taxiing
behind

1.5 Taxi Instructions

1.5.1 Taxi instructions issued by a controller will always contain a clearance limit, which is
the point at which the aircraft must stop, unless further permission to proceed is
given. For departing aircraft, the clearance limit will normally be the holding point of
the runway in use, but it may be any other position on the aerodrome depending on
the prevailing traffic. Taxi clearances should, wherever possible, be noted down by
pilots.

Borton Tower, G-ABCD, T67 by the
south side hangars request taxi for
VFR flight to Walden, 2 POB

G-ABCD, taxi holding point G2
runway 24 via taxiway Charlie, QNH
967 hectopascals

NOTE: POB (total persons on board) may be added, e.g. where a flight plan is not

required and has not been filed.

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Taxi holding point G2 runway 24 via
taxiway Charlie, QNH 967
hectopascals, G-ABCD

G-ABCD, request surface wind

G-CD, surface wind 220 6

G-CD, request runway 14

G-CD, after the Seneca coming from
your left, taxi holding point B1
runway 14

Following the Seneca from the left,
taxi holding point B1 runway 14,
G-CD

Borton Tower, G-ABCD, T67 at the
fuel station VFR to Walden request
taxi

Borton Tower, G-ABCD, at the fuel
station request taxi to flying club

G-CD, runway 06, QNH 1008, taxi
holding point B2 runway 14 via
taxiway Alpha

QNH 1008, G-CD, request taxiway
Bravo, and backtrack runway 06

G-CD, taxi holding point H1 runway
06 via taxiway Bravo

Taxi holding point H1 runway 06 via
taxiway Bravo, G-CD

G-CD, taxi holding point A1 runway
24 via Charlie

Taxi holding point A1 runway 24 via
Charlie, G-CD

G-CD, holding point A1 runway 24
request cross

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G-CD, negative. Hold position.

Holding, G-CD

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G-CD, taxi to the flying club, via A1
cross runway 24 report vacated

Taxi to the flying club, via A1 cross
runway 24, Wilco, G-CD

G-CD, runway vacated

G-CD

NOTES: 1 Instruction to report vacated may be omitted when aerodrome control

has continuous sight of the aircraft crossing.

2 For helicopters the phrase “Air-taxi....” may be used in place of “Taxi....”.

1.5.2 Controllers are not to instruct aircraft or vehicles to cross illuminated red stop-bars
used at runway and intermediate taxiway holding positions. The aerodrome operator
may decide, on the grounds of safety, that inoperable stop-bars and associated
taxiways be withdrawn from service and alternative routes used where practicable.
On the occasions when the withdrawal of inoperable stop-bars is not possible and the
stop-bars cannot be readily suppressed, under exceptional circumstances, an aircraft
may be instructed to cross such an illuminated stop-bar.

G-CD stop-bar unserviceable,
cross red stop-bar at A1

G-CD stop-bar unserviceable, cross
red stop-bar, via A1 line up runway
24

Cross red stop-bar at A1, G-CD

Cross red stop-bar, via A1 line up
runway 24, G-CD

1.5.3 If the instructions given to surface traffic involve crossing a runway in use, clearance
to cross should normally be withheld until no confliction exists. However, to achieve
greater efficiency of operation, clearance to cross may be given subject to aircraft,
which are landing or taking off. The conditional clearance shall contain sufficient
information to enable the pilot of the taxiing aircraft or vehicle driver to identify the
other traffic and should be related to one movement only.

BIGJET 347, after the landing
A320, via Bravo 1 cross runway 26,
report vacated

G-CD, after the landing PA28 cross
and report vacated

After the landing A320, via Bravo 1
cross runway 26, wilco, BIGJET 347

After the landing PA 28, cross, wilco,
G-CD

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1.5.4 When a clearance to cross a runway in use is issued, a report vacated instruction shall
be included. However, this instruction may be omitted when the controller has
continuous sight of the aircraft or vehicle crossing.

G-CD, after the departing Seneca,
via Kilo 4 cross runway 02

After the departing Seneca, via Kilo
4 cross runway 02, G-CD

1.5.5 When passing taxi instructions that will position an aircraft to cross a runway the
controller may, optionally, insert the phrase ‘hold short of’ prior to the runway
designator. This phrase is intended to reinforce the need to stop at the holding point.

BIGJET 347, taxi holding point C3,
hold short of runway 36

BIGJET 347, cross runway 36, taxi
holding point A1, hold short of
runway 09

Taxi holding point C3 hold short of
runway 36, BIGJET 347

Cross runway 36, taxi holding point
A1, hold short of runway 09,
BIGJET 347

1.5.6 Where an ATIS broadcast is established the controller does not need to pass
departure information to the pilot when giving taxi instructions. He will, however,
check that the aircraft is in possession of the latest QNH.

BIGJET 347, information Bravo,
QNH 1020 request taxi

BIGJET 347, now information
Charlie, new QNH 1021, after the
B747 passing left to right taxi holding
point A1 runway 28

QNH 1021, after B747 left to right
taxi holding point A1 runway 28,
BIGJET 347

1.6 Pre-Departure Manoeuvring

1.6.1 Meticulous care has been taken to ensure that the phraseology which is to be
employed during the pre-departure manoeuvres cannot be interpreted as a take-off
clearance. This is to avoid any misunderstanding in the granting or acknowledgement
of take-off clearances and the serious consequences that could result.

1.6.2 At busy aerodromes with a separate ground and tower function, aircraft are usually
transferred to the tower frequency at or approaching the holding point.

BIGJET 347, contact Tower 118.9

Tower 118.9, BIGJET 347

1.6.3 It may be necessary for the controller to instruct the pilot to hold at a specified holding
point. Where appropriate the controller should include the reason for the instruction.

BIGJET 347, hold at Bravo 2

BIGJET 347, hold at Bravo 1, 2
aircraft to depart before you from
runway 20

Hold at Bravo 2, BIGJET 347

Hold at Bravo 1, BIGJET 347

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1.6.4 Many types of aircraft carry out engine checks prior to departure and are not always
ready for take-off when they reach the holding point.

G-CD, report ready for departure

G-CD, ready for departure

Wilco, G-CD

G-CD, line up

Line up, G-CD

1.6.5 When line-up will take place at a position other than for a full-length runway departure
the intermediate 'Holding Point' designator shall be included in the line-up instruction.
Controllers may include the runway 'Holding Point' designator in any other line-up
instruction when considered necessary.

G-CD, ready for departure

G-CD, via C2 line-up runway 28

G-CD, line-up via C2 runway 28

1.6.6 For reason of expedition, a controller may wish to line-up an aircraft for departure
before conditions allow take-off.

BIGJET 347, via holding point A1
line-up and wait runway 26, one
aircraft to depart before you from
holding point A2

Via holding point A1 line-up and wait
runway 26, number two for
departure, BIGJET 347

1.7 Take-Off Clearance

1.7.1 Except in cases of emergency, messages will not be transmitted to an aircraft in the
process of taking off or in the final stages of an approach and landing.

1.7.2 Controllers will use the following phraseology for take off.

G-CD, cleared for take-off

Cleared for take-off, G-CD

NOTE: The surface wind will be passed if there is a significant difference to that

already passed.

1.7.3 The averaging period for wind observations is two minutes for reports used at an
aerodrome for take-off and landing and for wind indicators in air traffic service units.
The instantaneous surface wind should be available to be given to pilots on request
particularly at aerodromes supporting primarily the operations of aircraft whose
maximum total weight authorised is 5,700 kg or less. When a pilot requests the
instantaneous surface wind, the word "instant" is to be inserted to indicate that the
wind being reported is not the two minute average.

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G-CD, request instant wind

G-CD, instant wind 270 7

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1.7.4 A take-off clearance shall be issued separately from any other clearance message.

1.7.5 For traffic reasons a controller may consider it necessary for an aircraft to take off
without any delay. Therefore, when given the instruction ‘cleared for immediate take­off’, the pilot is expected to act as follows:

a) At the holding point: taxi immediately on to the runway and commence take-off

without stopping the aircraft.

b) If already lined up on the runway: take-off without delay. Should an immediate

take-off not be possible, the pilot is to advise the controller.

BIGJET 347, cleared for immediate
take-off

G-CD, Piper Cub 2 miles on final
approach. Cleared for immediate
take-off wind 240 8 knots

Cleared for immediate take-off,
BIGJET 347

Cleared for immediate take-off,
G-CD

1.7.6 For reason of expedition a controller may wish to line-up an aircraft for departure
before conditions allow take-off.

BIGJET 347, line-up and wait –
vehicle crossing upwind end of
runway

BIGJET 347, cleared for take-off

Line-up and wait, BIGJET 347

Cleared for take-off, BIGJET 347

1.7.7 In poor visibility the controller may prefix the clearance with the runway designator
and request the pilot to report when airborne.

BIGJET 347, runway 28 cleared for
take-off report airborne

Runway 28 cleared for take-off.
Wilco, BIGJET 347

BIGJET 347, airborne

BIGJET 347, contact Radar 121.750

Radar 121.75, BIGJET 347

1.7.8 Conditional clearances are only to be provided subject to conditions specified by the
relevant authority. Conditional phrases will not be used for movements affecting the
active runway(s), except when the aircraft or vehicles concerned are seen by the
controller and pilot. Conditional clearances are to relate to one movement only and, in
the case of landing traffic, this must be the first aircraft on approach. A conditional
instruction shall be given as follows:

a) callsign;
b) the condition;
c) identification of subject of the condition;

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d) the instruction.

BIGJET 347, after the landing DC9,
line up

After the landing DC9 line up,
BIGJET 347

1.7.9 When several runways are in use and/or there is any possibility that the pilot may be
confused as to which one to use, the runway number will be stated prior to the
clearance.

BIGJET 347, runway 09 left cleared
for take-off

Runway 09 left cleared for take-off,
BIGJET 347

1.7.10 Local departure instructions may be given prior to the take-off clearance. Such
instructions are normally given to ensure separation between aircraft operating in the
vicinity of the aerodrome.

BIGJET 347, after departure track
extended centre line

BIGET 347, after departure climb
straight ahead

BIGJET 347, after departure fly
heading 240 degrees, climb to
altitude 6000 feet

After departure track extended
centre line, BIGJET 347

After departure climb straight
ahead, BIGJET 347

After departure fly heading 240
degrees, climb to altitude 6000 feet,
BIGJET 347

G-CD, after departure right hand
circuit

G-CD, after departure track 270
degrees from Borton until reaching
altitude 3000 feet before setting
course

After departure right hand circuit,
G-CD

After departure track 270 degrees
from Borton until reaching altitude
3000 feet before setting course,
G-CD

1.7.11 Revised clearances and post departure instructions for aircraft on the runway or at the
holding position shall be prefixed with an instruction to hold position.

BIGJET 347, Hold position, after
departure climb straight ahead to
altitude 2500 feet QNH 1014 before
turning right

G-CD, after departure request right
turn

BIGJET 347, Holding, after departure
climb straight ahead to altitude 2500
feet, QNH 1014 before turning right.

BIGJET 347, Cleared for take-off

Cleared for take-off, BIGJET 347

G-CD, Hold position, right turn
approved

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G-CD, Holding, right turn approved

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G-CD, Cleared for take-off

Cleared for take-off, G-CD

1.7.12 Due to unexpected traffic developments or a departing aircraft taking longer to take­off than anticipated, it is occasionally necessary to rescind the take-off clearance or
quickly free the runway for landing traffic.

BIGJET 347, take-off immediately or
vacate runway

BIGJET 347, take-off immediately or
hold short of runway

Taking-off, BIGJET 347

Holding, BIGJET 347

1.7.13 When an aircraft is about to take-off or has commenced the take-off roll, and it is
necessary that the aircraft should abandon take-off, the aircraft will be instructed to
cancel take-off or stop immediately; these instructions will be repeated.

G-CD, hold position, cancel take-off
I say again cancel take-off,
acknowledge

BIGJET 347, stop immediately I say
again, BIGJET 347, stop
immediately, acknowledge

Holding, G-CD

Stopping, BIGJET 347

NOTE: Military procedures for cancelled take-offs appear in Chapter 10 paragraph

3.4.

1.7.14 When a pilot abandons take-off he should, as soon as practicable, inform the tower
that he is doing so. Likewise, as soon as practicable, he should inform the tower of
the reasons for abandoning take-off if applicable, and request further manoeuvring
instructions.

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BIGJET 347, stopping

BIGJET 347

BIGJET 347, request backtrack for
another departure

BIGJET 347, backtrack approved

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RUNWAY IN USE

SURFACEWIND

LIVE SIDE

DEAD SIDE

4 miles or less

Beyond 4 miles

1.8 Aerodrome Traffic Circuit

1.8.1 Designated Positions in the Traffic Circuit

Figure 1 Designated positions in the traffic circuit

Typical Left-Hand Circuit

Position 1 Aircraft reports on 'Downwind' leg.

Position 2 Aircraft reports 'Late downwind' if it is on the downwind leg, has been unable

to report 'Downwind' and has passed the downwind end of the runway.

Position 3 Aircraft reports 'Base' leg (if required).

Position 4 Aircraft reports ‘Final’. Clearance to land issued here.

Position 5 Aircraft reports 'Long final' (between 8 and 4 miles) when aircraft is on a

straight in approach.

NOTE 1: For light aircraft operations, circuit dimensions may be reduced but the relative

RTF reporting points are maintained.

NOTE 2: For details of the standard overhead joining procedure see Aerodrome Traffic

Circuit (Chapter 4 Paragraph 1.8.3) and RTF Reports at Unattended Aerodromes
(Chapter 4 Paragraph 6.1).

NOTE 3: For details of military visual circuit patterns see Chapter 11 paragraph 1.4

1.8.2 Requests for circuit-joining instructions should be made in sufficient time for a
planned entry into the circuit taking other traffic into account. Where ATIS is
established, receipt of the broadcast should be acknowledged in the initial call to an
aerodrome. When the traffic circuit is a right-hand pattern it shall be specified. A left­hand pattern need not be specified although it is essential to do so when the circuit
direction is variable.

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Walden Tower, G-ABCD, request join G-ABCD, Walden Tower, pass your

message

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G-ABCD, T67 10 miles south
altitude 2500 feet Wessex 1008

G-CD, join righthand downwind
runway 27 height 1000 feet QFE
1006

Join righthand downwind runway 27
height 1000 feet QFE 1006, G-CD

1.8.3 In some circumstances, an aircraft may be instructed to complete a standard
overhead join which comprises the following:

a) Overfly at 2000 ft above Aerodrome Elevation.
b) If not already known, determine the circuit direction from the signals square, other

traffic or windsock.
c) Descend on the ‘dead side’ to circuit height.
d) Join the circuit by crossing the upwind end of the runway at circuit height.
e) Position downwind.
NOTE: Pilots should ensure they have checked beforehand whether specific joining

procedures apply; otherwise an ‘overhead join’ (which actually takes a joining
aircraft around the aerodrome) is the preferred method of joining the circuit
pattern. Aerodromes where specific procedures apply will notify such
differences in the UK AIP.

G-CD, join overhead runway 20
height 2000 feet QFE 997
hectopascals, report aerodrome in
sight

Join overhead runway 20 height
2000 feet QFE 997 hectopascals,
wilco, G-CD

1.8.4 Depending on prevailing traffic conditions and the direction from which an aircraft is
arriving, it may be possible to make a straight-in approach.

Walden Tower, G-ABCD, request join G-ABCD, Walden Tower, pass your

message

G-ABCD, T67 10 miles south
altitude 2500 feet Wessex 1008
request straight in approach runway
34

G-CD, cleared straight in approach
ru

nway 34 wind 260 degrees

QFE 1006 report final

Cleared straight in approach runway
34 QFE 1006. Wilco, G-CD

5 knots

1.8.5 The pilot having joined the traffic circuit makes routine reports as required by local
procedures.

31 March 2011

G-CD, downwind

G-CD, number 2 follow the
Cherokee on base

Number 2, Cherokee in sight, G-CD

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G-CD, base

G-CD, final

G-CD

G-CD, runway 34 cleared to land
wind 270 7

Runway 34 cleared to land, G-CD

1.8.6 Where necessary the controller may instruct the pilot to report at a specified position.

G-CD, report overhead

G-CD, report downwind

G-CD, report long final

Wilco, G-CD

Wilco, G-CD

Wilco, G-CD

G-CD, report base

Wilco, G-CD

1.8.7 It may be necessary in order to co-ordinate traffic in the circuit, to issue a pilot his
number in the sequence along with the position of the preceding aircraft and delaying
action if necessary.

G-CD, extend downwind number 2,
number 1 is a Cherokee left-hand
downwind

G-CD, number 2, follow the
Cherokee ahead

G-CD, for spacing orbit right number
2, number 1 is a Cherokee on final,
report again on base

Extend downwind, number 2, G-CD

Follow Cherokee ahead, G-CD

Orbit right, wilco, G-CD

1.8.8 In order to save taxiing time when flying training in the traffic circuit pilots may wish
to carry out a ‘touch and go’, i.e. the aircraft lands, continues rolling and takes-off,
without stopping.

17 November 2011

G-CD, downwind touch and go

G-CD, report final

G-CD, final

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G-CD, runway 34 cleared touch and
go surface wind calm

Runway 34 cleared touch and go,
G-CD

or,

G-CD, unable to approve due traffic,
make full stop landing runway 34
cleared to land, surface wind calm

Runway 34 cleared to land, G-CD

1.8.9 It is helpful for circuit management purposes if a controller is informed when an
aircraft which has been engaged in multiple approaches is on his last circuit.

G-CD, downwind to land

G-CD, report final

1.9 Final Approach and Landing

1.9.1 A ‘final’ report is made when an aircraft has turned onto final approach. If the turn on
is made at a distance greater than 4 NM from touchdown a ‘long final’ report is made.
The landing/touch and go/low approach clearance will include the runway designation.

G-CD, final

BIGJET 347, long final

G-CD, runway 34 cleared to land
surface wind 270 7

Runway 34 cleared to land, G-CD

BIGJET 347, report final surface
wind 260 18

Wilco, BIGJET 347

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BIGJET 347, final

BIGJET 347, runway 28 cleared to
land, wind 270 20

Runway 28 cleared to land,
BIGJET 347

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NOTE 1: Military phraseology for a gear check appears in Chapter 10 paragraph 3.6.
NOTE 2: Where established, an ‘outer marker’ instead of a 'final' report may be

made.

1.9.2 Where a controller cancels a landing clearance but feels that a landing clearance will
be re-issued in good time for the aircraft to make a safe landing, he should, if time
permits, give the reason for cancelling the landing clearance.

BIGJET 347, continue approach,
cancel landing clearance (reason),
acknowledge

Landing clearance cancelled,
continuing approach, BIGJET 347

1.9.3 If available, the instantaneous surface wind should be provided to the pilot on request.

G-CD, runway 13 cleared to land,
instant surface wind 270 15

1.9.4 The runway may be obstructed when the aircraft makes its ‘final’ report at 4 NM or
less from touchdown but is expected to be available in good time for the aircraft to
make a safe landing. On these occasions, the controller will delay landing clearance.

G-CD, final

G-CD, continue approach, wind
270 5

Continue approach, G-CD

The controller may or may not explain why the landing clearance has been delayed
but the instruction to ‘continue’ IS NOT an invitation to land and the pilot must wait
for landing clearance or initiate a missed approach (see Chapter 4, paragraph 1.10.3).

1.9.5 A landing aircraft may be permitted to touch down before a preceding landing aircraft
has vacated the runway provided that:

a) the runway is long enough to allow safe separation between the two aircraft and

there is no evidence to indicate that braking may be adversely affected;
b) it is during daylight hours;
c) the preceding landing aircraft is not required to backtrack in order to vacate the

runway;
d) the controller is satisfied that the landing aircraft will be able to see the preceding

aircraft which has landed, clearly and continuously, until it has vacated the runway;

and
e) the pilot of the following aircraft is warned. (Responsibility for ensuring adequate

separation rests with the pilot of the following aircraft.)

BIGJET 347, runway 28, land after
the B737, wind calm

Land after the B737, BIGJET 347

Military phraseology for clearances with an occupied runway is shown in Chapter 10
paragraph 3.24.

1.9.6 A pilot may request to fly past the control tower or other observation point for the
purpose of visual inspection from the ground.

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G-CD, request low pass

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1.9.7 If the low pass is made for the purpose of observing the undercarriage, one of the
following replies could be used to describe its condition but these examples are not
exhaustive:

a) landing gear appears down;
b) right (or left, or nose) wheel appears up (or down);
c) wheels appear up;
d) right (or left, or nose) wheel does not appear up (or down).

1.9.8 A pilot may request permission to make a low approach along the runway, without
intending to land.

G-CD, request low approach

G-CD, runway 34 cleared low
approach

1.9.9 If the runway in use is occupied by aircraft or vehicles, an approaching aircraft may be
cleared to carry out a low approach which includes a descent not below a specified
height or altitude. The minimum height or altitude is defined in regulatory
documentation and/or local instructions as appropriate. In such circumstances, the
pilot is to be informed of the aircraft or vehicles on the runway.

1.9.9.1 The following example assumes an aircraft operating on QNH.

BIGJET 347, request low approach

BIGJET 347, runway 05 cleared low
approach, not below altitude
(number) feet, vehicle on runway

Runway 05 cleared low approach,
not below altitude (number) feet,
BIGJET 347

1.9.9.2 Where the aircraft is known to be operating on QFE, the instruction is as follows.

BIGJET 347, request low approach

BIGJET 347, runway 05 cleared low
approach, not below height
(number) feet, vehicle on runway

Runway 05 cleared low approach,
not below height (number) feet,
BIGJET 347

1.10 Missed Approach

1.10.1 Instructions to carry out a missed approach may be given to avert an unsafe situation.
When a missed approach is initiated cockpit workload is inevitably high. Any
transmissions to aircraft going around shall be brief and kept to a minimum.

BIGJET 347, go around I say again go
around, acknowledge

Going around, BIGJET 347

1.10.2 An aircraft on an instrument approach is to carry out the published missed approach
procedure and an aircraft operating VFR is to continue into the normal traffic circuit
unless instructions are issued to the contrary.

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1.10.3 In the event of missed approach being initiated by the pilot, the phrase ‘going around’
shall be used.

G-CD, going around

G-CD, Roger

1.10.4 Missed Approach Phraseology used by military controllers is shown in Chapter 10
paragraph 3.17.

1.11 Runway Vacating and Communicating after Landing

1.11.1 Unless absolutely necessary, controllers will not give taxi instructions to pilots until
the landing roll is complete. Unless otherwise advised, pilots should remain on tower
frequency until the runway is vacated.

BIGJET 347, vacate left

BIGJET 347, when vacated contact
Ground 118.350

Vacate left, BIGJET 347

When vacated Ground 118.350,
BIGJET 347

Kennington Ground, BIGJET 347,
runway vacated

BIGJET 347, Kennington Ground,
taxi to Stand 27 via taxiway Alpha

G-CD, taxi to the end, report runway
vacated

1.12 Essential Aerodrome Information
Essential Aerodrome Information is information regarding the manoeuvring area and

its associated facilities which is necessary to ensure the safe operation of aircraft.
Essential Aerodrome Information is passed to aircraft whenever possible prior to
start-up or taxi and prior to the commencement of final approach.

Taxi to Stand 27 via taxiway Alpha,
BIGJET 347

Taxi to the end, Wilco, G-CD

G-CD, runway vacated

G-CD, give way to the Cherokee on
taxiway Alpha, taxi to the flying club

Give way to the Cherokee on
taxiway Alpha, taxi to the flying club,
G-CD

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BIGJET 347, caution construction
work at the end of Stand 37

... caution work in progress ahead
north side of taxiway Alpha

... caution centre line taxiway lighting
unserviceable

... caution PAPIs runway 27
unserviceable

... caution large flock of birds north of
runway 27 near centre taxiway

... Message from the aerodrome
operator, rescue and fire facilities
reduced to category (number)

1.13 Arrestor Systems at Military Aerodromes

1.13.1

Phraseology describing arrestor systems at military aerodromes appears in Chapter 10
paragraph 3.7.

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2 Aerodrome Flight Information Service Phraseology

2.1 Introduction

2.1.1 Concise and unambiguous phraseology used at the correct time is vital to the smooth,
safe and expeditious running of an aerodrome and associated ATZ. It is not only the
means by which instructions and information are passed but it also assists pilots in
maintaining an awareness of other traffic in their vicinity, particularly in poor visibility
conditions.

2.1.2 Messages will not be transmitted to an aircraft during take-off, the last part of final
approach or the landing roll, unless it is necessary for safety reasons, because it will
be distracting to the pilot at a time when the cockpit workload is often at its highest.

2.1.3 Local procedures vary from aerodrome to aerodrome and it is impossible to give
examples to cover every situation which may arise at the multiplicity of different types
of aerodrome. Information in addition to that shown in the examples, e.g. time
checks, etc. may be provided as necessary.

2.2 Type of Service

2.2.1 As described in Chapter 2 the type of service provided at an aerodrome falls into one
of three categories. In this section the examples are confined to those used by Flight
Information Service Officers (FISOs). Phraseology for air traffic controllers may be
found in Chapter 4 paragraph 1 and that for Air/Ground Communication Service
Operators in Chapter 4 paragraph 5.

2.2.2 Whilst the RTF procedures used by air traffic controllers form the main content of this
publication it should be noted that the phraseology used by FISOs at aerodromes is
different from that used by controllers. A FISO at an aerodrome provides a service to
give information useful for the safe and efficient conduct of flights in the Aerodrome
Traffic Zone. From the information received pilots will be able to decide the
appropriate course of action to be taken to ensure the safety of flight. Generally, the
FISO is not permitted to issue instructions or advice to pilots of his own volition.
However, in granting or refusing permission under Rule 40 and 41 of the Rules of the
Air, FISOs at aerodromes are permitted to pass instructions to vehicles and personnel
operating on the manoeuvring area and information and instructions to aircraft moving
on the apron and specific parts of the manoeuvring area. Elsewhere on the
manoeuvring area and at all times in the air, information only shall be passed to pilots.
Further details on the passing of instructions by FISOs at aerodromes are contained
in CAP 410 Manual of Flight Information Services - Part B Aerodrome.

2.2.3 FISOs are also permitted to pass messages on behalf of other agencies and
instructions from the aerodrome operator. If they do so, they will include the name of
the agency so that pilots will be aware that the message comes from a legitimate
source, e.g. ‘Wrayton Control clears you to join ...’.

2.2.4 With the exception of issuing instructions to aircraft on the ground, FISOs are
reminded that the service they provide is an information service relating to the ATZ
and aerodrome. They must ensure that the information given to pilots is distinct and
unambiguous, as pilots will use this information for the safe and efficient conduct of
their flights.

2.2.5 A FISO may request pilots to make position reports e.g.downwind, final etc. These
requests do not have the status of instructions, although it is expected that most
pilots will comply.

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2.2.6 From the instructions and information provided by the FISO to aircraft on the
appropriate areas of the aerodrome, the pilot will be able to determine if it is safe to
taxi. From the information provided by the FISO, the pilot will determine if it is safe to
land, take-off or transit the ATZ. FISOs are not permitted to refuse entry into the ATZ
when requested by a pilot. The aerodrome authority may decide that they will not
permit an aircraft to land at their aerodrome and request that the FISO pass this
message on. Such a message must be prefixed: ‘Message from the aerodrome
authority...’ FISOs may not issue such messages of their own volition.

2.3 AFIS Phraseology for Ground Movement, Take-Off, Landing and Transit

2.3.1 RTF messages transmitted on aviation VHF frequencies should normally comprise
callsign and text as described earlier in this document.

2.3.2 Ground movement instructions are similar for aircraft, vehicles and tractors towing
aircraft but the operative word in the message is ‘taxi’, ‘proceed’ and ‘tow’
respectively.

Table 1

Phraseology

Taxi Instructions prior to take off,
after landing and other ground
movement.

Aircraft at the holding point of
runway to be used for departure
ready for take-off

(Aircraft callsign) taxi holding point (designation) runway
(designation) via (route), surface wind (number) degrees
(number) knots, QNH/QFE (pressure) (hectopascals), left/right
hand circuit.
(Aircraft callsign) taxi to stand (designation) via (route).
(Aircraft callsign) taxi to (location).
When necessary, detailed taxiing instructions e.g. turn left
from the apron and take the first intersection right.
(Aircraft callsign) after the (aircraft type) passing (e.g. left to
right) taxi holding point (designation) runway (designation)
surface wind (number) degrees (number) knots, QNH/QFE
(pressure) (hectopascals), left/right hand circuit.
(Aircraft callsign) follow the (aircraft type) (position of aircraft).
(Aircraft callsign) hold position.
Note: FISOs are permitted to pass instructions to helicopters
engaged in air taxiing. However, when the pilot reports ready to
depart, the FISO shall pass information. For all inbound
helicopters, information shall be passed until they land or reach
the hover prior to air taxiing to the parking area. Thereafter,
instructions shall be given until the helicopter touches down.

(Aircraft callsign) hold position.
(Aircraft callsign) take off at your discretion, surface wind
(number) degrees (number) knots.
(Aircraft callsign) traffic is (traffic information) take off at your
discretion, surface wind (number) degrees (number) knots.*

*Note: Pilots will notify the FISO of their intentions.
Note: When several runways are in use and/or there is any

possibility that the pilot may be confused as to which runway
to use, the runway number will be stated.

Aircraft at the holding point of
runway to be used for departure
ready for take-off with the
possibility of requiring a backtrack

17 November 2011

(Aircraft callsign) do you require to backtrack the runway?*

*Note: Pilots will notify the FISO of their intentions.
Note: When several runways are in use and/or there is any

possibility that the pilot may be confused as to which runway
to use, the runway number will be stated.

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Table 1 (Continued)

Aircraft requiring a backtrack (Aircraft callsign) report entering the runway.

(Aircraft callsign) report lining up.**
(Aircraft callsign) traffic is (traffic information) report entering
the runway and lining up.**
(Aircraft callsign) the runway is occupied (details of traffic).
Report lining up.**
(Aircraft callsign) the (aircraft type) has landed to vacate and
there is a (aircraft type) on a 2 mile final. Report lining up.**
(Aircraft callsign) backtrack as required, surface wind (number)
degrees (number) knots, take off at your discretion.**
**Note: Pilots will notify the FISO of their intentions.

Instructions for crossing runway in
use

(Aircraft callsign) cross runway (designation) at (point of
crossing). Report vacated.*
(Aircraft callsign) cross, report vacated.*
(Aircraft callsign) negative, hold position, I will call you.
*‘Report vacated’ instructions may be omitted when the FISO
has continuous sight of the vehicle or aircraft crossing.

When airborne (Aircraft callsign) roger, report (downwind or position).

Aircraft wishes to transit the ATZ (Aircraft callsign) (traffic and aerodrome information), report

entering/overhead/leaving.

Aircraft wishes to enter the ATZ
for landing

(Aircraft callsign) runway (designation) left/right hand circuit,
surface wind (number) degrees (number) knots, QNH/QFE
(pressure) (hectopascals) (traffic information and essential
aerodrome information as appropriate).

Aircraft reports joining the circuit (Aircraft callsign) roger, (traffic information) report downwind/

base/final.

Aircraft reports final (If number 1 and runway is clear)

(Aircraft callsign) land/touch and go at your discretion, surface
wind (number) degrees (number) knots.
OR

(If aircraft has traffic ahead on final)

(Aircraft callsign) roger, (number) aircraft ahead on final.
OR
(If the runway is occupied)
(Aircraft callsign) the runway is occupied (traffic information).

Aircraft expects Air Traffic Control
Service

17 November 2011

(Aircraft callsign) no ATC Service available. (TYPE OF SERVICE)
only.

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2.3.3 Examples of typical FISO/Pilot RTF exchanges are detailed below.

G-ABCD, request taxi G-CD, taxi holding point C2, runway

06 via taxiway C, surface wind 060
10 knots, QNH 998 hectopascals,
left hand circuit

Roger, taxi to holding point C2,
runway 06 via taxiway C, QNH 998
hectopascals, G-CD

at the holding point...

G-CD, C2 Ready for departure G-CD, Hold position

G-CD, Take-off at your discretion,
surface wind 270 degrees 15 knots

G-CD, Traffic is a Cessna 172 base
leg, take off at your discretion,
surface wind 270 15

G-CD, Via C2 take-off at your
discretion, surface wind 270 15

G-CD, Do you require to backtrack
the runway?

Holding, G-CD

Taking off, G-CD

Taking off, G-CD

Via C2 taking off, G-CD

Affirm, G-CD

17 November 2011

G-CD, Traffic is a Cessna 172 base
leg, via C2 report entering the
runway and lining up

Holding, wilco, G-CD

G-CD, Entering runway 27 G-CD, Roger

G-CD, Lining up runway 27

G-CD, Take off at your discretion,
surface wind 270 15

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CAP 413 Radiotelephony Manual

Taking off, G-CD

G-CD, Report downwind

In the circuit...

G-CD, Downwind to land G-CD, Roger, traffic is a Cessna 172

base leg, report final

Wilco, G-CD

G-CD, Final

When the runway is available...

G-CD, Land at your discretion,
surface wind 050 10 knots

After landing...

G-CD, after the Cessna 172 taxiing
right to left, taxi to the aero club, via
taxiway Charlie

G-CD, Roger, Cessna 172 ahead on
final

Roger, G-CD

Roger, G-CD

Roger, after the Cessna 172, taxi to
the aero club, via taxiway Charlie,
G-CD

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3 Aerodrome Phraseology for Helicopters

3.1 Introduction

3.1.1 Rotary-wing flight characteristics mean that helicopter operations at aerodromes can
differ significantly from fixed-wing operations. This section describes standard
phraseology and procedures to address the different requirements for helicopter
lifting, taxiing, taking-off and landing (including the approach and departure phases),
particularly at aerodromes where rotary-wing and fixed-wing operations are
integrated.

3.1.2 Standard phraseology should be used in all situations for which it is specified. When
standardised phraseology cannot serve an intended transmission, plain language
should be used. The use of plain language may further assist when describing rotary­wing aircraft manoeuvres. Care should be exercised to ensure that all parties involved
achieve clear understanding.

3.1.3 The phraseology described in this section is intended for general use. However, the
examples of taxiing phraseology describe communications specific to aerodromes at
which ATC or AFIS is provided. Phraseology examples for take-off and landing are
specific to communications at aerodromes with ATC.

3.2 Helicopter Callsigns

3.2.1 Aircraft callsigns to be used are described in Chapter 2 paragraph 1.8. Provision is
made for the name of the aircraft manufacturer, or the aircraft model, to be used
before the aircraft registration (in full or abbreviated form). If considered appropriate,
the pilot or ATSU may replace manufacturer’s name or aircraft model with the term
‘Helicopter’ where this may benefit the ATSU or other aircraft (see phraseology
examples paragraphs 3.8.5 and 3.8.6).

Table 2

Full callsign Abbreviation

Helicopter G-ABCD Helicopter CD

3.3 Helicopter Phraseology for Taxiing

3.3.1 These procedures are for helicopters taxiing for departure, or after landing, or for
general manouevring on the aerodrome. Phraseology and procedures for specific
manouevring on the aerodrome, for example for training purposes, should be
described in local procedures.

3.3.2 The term 'LIFT' shall describe a manoeuvre where the helicopter gets airborne and
enters a 'HOVER'.

3.3.3 'HOVER' describes a manoeuvre where the helicopter holds position whilst airborne
in ground effect, waiting to proceed. Hover allows spot/axial turns (i.e. about the
central axis of the helicopter). When required, further instructions should
subsequently be transmitted to permit the helicopter to proceed.

3.3.4 The term 'AIR TAXI' shall be used when it is necessary for a helicopter to proceed at
a slow speed above the surface, normally below 20 knots and in ground effect (ICAO).

3.3.5 The instruction 'GROUND TAXI' shall be used for the movement of a helicopter, in
contact with the surface of the aerodrome, under its own power. This could be
required for a helicopter fitted with wheels, to reduce rotor downwash (ICAO).

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CAP 413 Radiotelephony Manual

3.3.6 An instruction to 'TAXI' leaves the pilot free to select the most appropriate method,
either ground taxi or air taxi. Pilots and controllers should use the term AIR TAXI or
GROUND TAXI when required to differentiate between air taxiing and ground taxiing
(for helicopters equipped with wheels).

NOTE 1: Air taxiing helicopters at aerodromes where ATC and AFIS are provided will

be issued with detailed taxi routes and instructions as appropriate to
prevent collisions with other aircraft and vehicles. Helicopters are expected
to follow procedures/routes on aerodromes appropriate to aeroplanes
unless otherwise authorised.

NOTE 2: ATC and AFIS units will normally avoid issuing instructions that result in

taxiing helicopters coming into close proximity with small aircraft or
helicopters and will normally give consideration to the effect of turbulence
from taxiing helicopters on arriving and departing light aircraft (ICAO).

3.3.7 For a helicopter taxiing, the instruction 'HOLD' shall indicate a requirement to come
to a standstill.

3.3.7.1 A helicopter air taxiing and instructed to 'HOLD', may hold in the hover or may touch
down and hold on the ground at the pilot’s discretion. If touch down is not authorised,
a helicopter may be instructed by the ATSU to 'HOLD IN THE HOVER'.

3.3.7.2 A helicopter ground taxiing and instructed to 'HOLD' shall hold on the ground, unless
a hover manoeuvre is specifically authorised or requested by the ATS unit.

3.3.8 ATC and AFIS will normally avoid issuing a frequency change instruction to a single­pilot helicopter hovering or air taxiing. If required and whenever possible, control
instructions from the next ATS unit will be relayed until the pilot is able to change
frequency (ICAO).

3.4 Helicopter Phraseology for Take-Off and Landing (ATC only)

3.4.1 At aerodromes, helicopter take-offs and landings may not be restricted to designated
runways or landing areas. With appropriate permission helicopters may take-off and
land at any location on the aerodrome. At aerodromes with an air traffic control
service, all movements are subject to the permission of the ATC unit.

3.4.2 At aerodromes with air traffic control service, when helicopters land or take-off on the
manoeuvring area, and within sight of the VCR the terms 'CLEARED TO LAND' and
'CLEARED FOR TAKE-OFF' shall be used to authorise the manoeuvres.

3.4.3 At aerodromes with air traffic control service, when helicopters land or take-off at
locations not on the manoeuvring area (e.g. apron, maintenance area, sites adjacent
the aerodrome), or locations not in sight of the VCR, or unlit locations at night, the
appropriate phrase 'LAND AT YOUR DISCRETION' or 'TAKE-OFF AT YOUR
DISCRETION' shall be used to authorise the manoeuvres. Relevant traffic information
on other aircraft (airborne or on the ground) shall also be passed.

3.4.4 The term 'TOUCH DOWN' shall be used to describe an aircraft (helicopter or fixed­wing) coming into contact with the surface in accordance with normal operation. A
clearance to land leaves the pilot of a helicopter free to either enter a low hover, or to
touch down, as appropriate.

3.5 Helicopter Hover Phraseology Examples (ATC and AFIS only)

31 March 2011

Borton Tower, G-ABCD, request
lift

Chapter 4 Page 24

G-ABCD, Borton Tower, lift and
hover, surface wind 040 degrees
6 knots

CAP 413 Radiotelephony Manual

3.6 Helicopter Taxiing Phraseology Examples (ATC and AFIS only)

3.6.1 Taxi Instruction

Borton Tower, G-ABCD, request
TAXI for departure runway 06

3.6.2 Air Taxi Instruction (if required)

Borton Tower, G-ABCD, request
Air Taxi for departure runway 06

3.7 Ground Taxi Instruction (if required)

Borton Tower, G-ABCD, request
ground taxi for departure runway
06

G-ABCD, Borton Tower, TAXI
holding point H1, runway 06, via
taxiway Golf

Taxi holding point H1 runway 06
via taxiway Golf, G-ABCD

Note: The use of ‘taxi’ indicates
the pilot is free to air taxi or
ground taxi at his/her discretion

G-CD, Borton, Air Taxi holding
point H1, runway 06, via taxiway
Golf

Air Taxi holding point H1 runway
06 via taxiway Golf, G-CD

G-ABCD, Borton Tower, ground taxi
holding point H1 runway 06 via
taxiway Golf

3.8 Helicopter Take-Off and Landing Phraseology Examples (ATC only)

3.8.1 Take-off on the Runway

G-CD, ready for departure

G-CD, Runway 06, Cleared for
take-off

Cleared for take-off, G-CD

3.8.2 Landing on the Runway

G-CD, final runway 06

G-CD, Runway 06, Cleared to
land, surface wind 060 10

Cleared to land, G-CD

3.8.3 Take-off from a designated Helicopter Landing Area on the Manoeuvring Area

G-CD, 'Area Whiskey' ready for
departure

G-CD, 'Area Whiskey' Cleared for
take-off

31 March 2011

Cleared for take-off, G-CD

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CAP 413 Radiotelephony Manual

3.8.4 Landing at a designated Helicopter Landing Area on the Manoeuvring Area.

G-ABCD, at the Power Station
to land 'Area Whiskey'

G-CD, 'Area Whiskey' Cleared to
land, surface wind 060 10

Cleared to land, 'Area Whiskey',
G-CD

3.8.5 Take-off from the Apron (or location not on the Manoeuvring Area) for a Direct
Departure (i.e. not following the visual circuit for departure).

Borton Tower, Helicopter
G-ABCD, beside the south side
hangars ready for direct
departure to Walden

Helicopter CD, Borton, direct
departure, surface wind 060 10,
QNH 997 hectopascals, no
reported traffic, Take-off at your
discretion

Taking-off, departing direct, QNH
997 hectopascals, Helicopter CD

3.8.6 Direct Arrival to the Apron (or location not on the Manoeuvring Area) for Landing.

Borton Tower, Helicopter
G-ABCD, 5 miles east inbound
to land Eastern Apron

Helicopter CD, at the Power
Station

Helicopter CD, Borton, route to
the eastern apron via the Power
Station, report at the Power
Station wind 060 10 QNH 997
hectopascals, runway 06 in use

Route to Eastern Apron via the
Power Station, wilco, QNH 997
hectopascals, Helicopter CD

Helicopter CD, traffic is a C172
taxiing from Stand 8 for taxiway
B, Land at your discretion,
surface wind 060 10

Roger, Landing Eastern Apron,
Helicopter CD

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4 Aerodrome Phraseology for Vehicles (ATC and AFIS only)

4.1 Introduction

4.1.1 The expeditious movement of vehicles plays an essential supporting role in the
operation of an aerodrome. Whenever possible the areas in which vehicles and
aircraft operate are segregated. However, there are many occasions when vehicles
need to move on the manoeuvring area either for maintenance purposes or in direct
support of aircraft operations.

4.1.2 Procedures governing the movement of vehicles vary widely from aerodrome to
aerodrome, but certain factors to be taken into account when driving on an aerodrome
are common to all:

a) in general, aircraft are by no means as manoeuvrable as ground vehicles;
b) the visibility from an aircraft cockpit for ground movement purposes is often

restricted compared with a vehicle.

Therefore when vehicles are operating in close proximity to aircraft, drivers should be
extremely vigilant and comply with Rule 42/43 of the Rules of the Air and, if
applicable, ATC instructions.

4.1.3 Correct RTF operating technique must be observed by all users. For all vehicles on
the movement area, it is important that a continuous listening watch is maintained,
not only in case of further instructions or information from the tower, but also so that
drivers can be aware of the movements, and intended movements, of other traffic
thereby reducing the risk of confliction.

4.1.4 The examples that follow are applicable to air traffic controllers and FISOs at

aerodromes only. Air/Ground Communication Service operators are not to pass
instructions and must use the phraseology they would use for the movement
of aircraft on the aerodrome.

4.2 Movement Instructions

4.2.1 Drivers on first call should state the ground station they are calling, identify
themselves by their vehicle call sign and state their position and intended destination.
Where the planned route includes crossing a runway, this should be included in the
initial call.

Metro Ground Works 21, stand 27
request proceed to work in
progress taxiway Hotel

Works 21, proceed to taxiway Hotel
via Kilo and Alpha

Proceed to taxiway Hotel via Kilo
and Alpha, Works 21

31 March 2011

Metro Ground, Works 3, stand 27
request proceed to work in
progress on taxiway Hotel, via
runway 34

Chapter 4 Page 27

Works 3, via Alpha 1 and Charlie 1
cross runway 34, proceed to
taxiway Hotel

Via Alpha 1 and Charlie 1 cross
runway 34, proceed to taxiway
Hotel, Works 3

CAP 413 Radiotelephony Manual

4.2.2 If the controller is too busy he will reply 'standby'. This means that the driver should
wait until the controller calls back. The driver shall not proceed until permission is
given.

4.2.3 When there is conflicting traffic the controller may reply 'hold position'. This means
that the driver shall not proceed until the controller calls back with permission. All
other replies should contain a clearly defined point to which the driver may proceed;
this may or may not be the intended destination. If it is not the intended destination
drivers must stop at this point and further permission shall be requested.

Tels 5, by the control tower
request proceed to hangar 3

Tels 5, at Charlie 8 request
proceed to hangar 3

Tels 5, hold position

Holding, Tels 5

Tels 5, proceed holding point
Charlie 1 runway 14, via Alpha and
Bravo

Proceed holding point Charlie 1
runway 14, Tels 5, via Alpha and
Bravo

NOTE: The vehicle has only been cleared as far as the holding position to await

runway crossing clearance and permission to proceed to hangar 3.

4.2.4 The controller/FISO may include the instruction 'hold short' to reinforce the point
beyond which the vehicle may not proceed.

Tels 5, by the control tower
request proceed to hangar 3

Tels 5, proceed holding point
Charlie 1, hold short of runway 14

Proceed holding point Charlie 1,
hold short of runway 14, Tels 5

4.2.5 Permission to proceed on the apron may include instructions to ensure safe
operations.

Tug 5, stand 21 request proceed
to stand 26

Checker 1, caution work in
progress north side of taxiway
Hotel

Fire 1, report your position Fire 1, taxiway Bravo by the

Tug 5, after the BIGJET BAe 146 on
your right has passed, proceed to
stand 26, caution jet blast

After the BAe 146 has passed
proceed stand 26, Tug 5

Roger, Checker 1

maintenance hangar

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4.3 To Cross a Runway

4.3.1 Drivers should note carefully the position to which they may proceed, particularly
where the intended route involves crossing a runway. Some aerodromes may have
procedures that will allow vehicles to proceed to a holding point on the movement
area and then request runway crossing instructions. Under no circumstances shall a
driver cross a runway unless positive permission has been given and
acknowledged. A runway vacated report should not be made until the vehicle (and
tow) is clear of the designated runway area.

4.3.2 In order to prevent unauthorised runway incursions, when an ATS Unit issues an
instruction to cross a runway, the appropriate holding point designator shall be
included in the instruction. A vehicle driver should query any instruction that identifies
a holding point designator inconsistent with the vehicle location, or the driver’s
request, before proceeding onto the runway.

Ops 1, on the Southern Apron
request proceed to Northern
Apron, via runway 27

Ops 1, holding point Alpha 2
runway 27 request cross

Ops 1, runway 27 vacated

Ops 1, proceed holding point Alpha
2 via Alpha and Bravo hold short of
runway 27

Proceed holding point Alpha 2 via
Alpha and Bravo hold short of
runway 27, Ops 1

Ops 1, via Alpha 2 and Charlie 2
cross runway 27, report vacated

Via Alpha 2 and Charlie 2, cross
runway 27, wilco, Ops 1

Ops 1, proceed to Northern Apron

Proceed to Northern Apron, Ops 1

Where it is not possible for the controller to issue permission to cross the runway,
alternative instructions may be given.

31 March 2011

Ops 1, on the Southern Apron
request proceed to Northern
Apron via runway 27

Ops 1, negative, proceed to
Northern Apron via Perimeter Road

Proceed to Northern Apron via
Perimeter Road, Ops 1

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CAP 413 Radiotelephony Manual

Positive permission must be given and acknowledged before a vehicle driver enters
a runway to carry out a specialised task.

Checker 1, holding point Charlie 1
request enter runway 05 for
surface inspection

Checker 1, via holding point Charlie
1 enter runway 05, report vacated

Via holding point Charlie 1 enter
runway 05, wilco, Checker 1

4.3.3 If a vehicle is operating on the runway, it will be instructed to vacate the runway when
it is expected that an aircraft will be landing or taking off.

Works 21, vacate runway 27 at
Alpha 1, report vacated

Vacate at Alpha 1, wilco, Works
21

Works 21, runway 27 vacated

Works 21

4.3.4 When a vehicle is moving on the movement area it may be necessary to inform the
vehicle of a potentially dangerous situation and to tell it to stop.

Works 21, stop immediately aircraft
crossing ahead

4.4 Vehicles Towing Aircraft
Drivers of vehicles required to tow aircraft should not assume that the receiving

station is aware that an aircraft is to be towed. The performance and manoeuvrability
of ground vehicles is obviously considerably reduced when towing aircraft and this is
taken into account when instructions to such vehicles are issued. Therefore, in order
to avoid any confusion, and as an aid to identification, drivers should state the type,
and where applicable the operator, of the aircraft to be towed in the first call.

Ground Tug 9, request tow
BIGJET BAe 146 from stand 25 to
maintenance hangar 3

Stopping, Works 21

Tug 9, tow approved from stand 25
to maintenance hangar 3 via
taxiway Echo

Tow approved from stand 25 to
maintenance hangar 3 via taxiway
Echo, Tug 9

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CAP 413 Radiotelephony Manual

Where it is necessary for the tug to push an aircraft back from a parking standing
before towing, this should be included.

Tug 9, request push back and tow
Blue Skies Boeing 737 from stand
25 to maintenance hangar

4.5 Low Visibility Procedures
Arrangements for notifying low visibility procedures vary between aerodromes and

may include a broadcast by the controller.

All stations, Metro Tower, low
visibility procedures in force

4.6 Messages regarding Safety of an Aircraft
Information regarding the safety of a specific aircraft should be transmitted to the

controller/FISO.

Ops 1, open ventilation panel
starboard side Bigjet Boeing 737
passing on taxiway Delta

4.7 Messages regarding Wildlife
Drivers should follow the procedures for their particular aerodrome when reporting

sightings of wildlife.

Fire 3, large flock of birds on grass
north of taxiway Bravo

4.8 Driver unsure of Position
If a driver is lost or unsure of the vehicle’s location he should inform the controller/

FISO immediately and follow instructions.

Tug 8, unsure of position

4.9 Broken-down Vehicle

Ops 1, roger

Tug 8, hold position I will call for
assistance

Holding, Tug 8

The driver of a broken-down vehicle should inform the controller/FISO immediately,
including precise information regarding the vehicle’s location and follow the
aerodrome’s procedures for broken-down vehicles.

Leader 2, holding point Charlie 1,
broken-down unable to move

4.10 Radio Failure
In the event of a radio failure, drivers should follow the procedures for their

aerodrome and comply with any light signals by the controller/FISO.

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5 Aerodrome Air/Ground Communication Service Phraseology

5.1 Introduction

5.1.1 Concise and unambiguous phraseology used at the correct time is vital to the smooth,
safe and expeditious running of an aerodrome and associated ATZ. It is not only the
means by which information is passed but it also assists pilots in maintaining an
awareness of other traffic in their vicinity, particularly in poor visibility conditions.

5.1.2 Messages will not be transmitted to an aircraft during take-off, the last part of final
approach or the landing roll, unless it is necessary for safety reasons, because it will
be distracting to the pilot at a time when the cockpit workload is often at its highest.

5.1.3 Local procedures vary from aerodrome to aerodrome and it is impossible to give
examples to cover every situation which may arise at the multiplicity of different types
of aerodrome. Information in addition to that shown in the examples, e.g. time
checks, etc. may be provided as necessary.

5.2 Type of Service

5.2.1 As described in Chapter 2 the type of service provided at an aerodrome falls into one
of three categories. In this section the examples are confined to those used by Air/
Ground Communication Service operators.

5.2.2 Whilst the RTF procedures used by air traffic controllers and FISOs form the main
content of this publication it should be noted that the phraseology used by Air/Ground
Communication Service operators is different from that used by controllers and
FISOs. This section describes only the phraseology provided by AGCS operators and
details of the service itself may be found in CAP 452 Aeronautical Radio Station
Operator’s Guide on the CAA web site or from the CAA’s printers (Details can be found
on the inside cover of this publication). Phraseology for aerodrome air traffic
controllers may be found in Chapter 4 paragraph 1 and that for FISOs in Chapter 4
paragraph 2.

5.2.3 An AGCS radio station operator is not necessarily able to view any part of the
aerodrome or surrounding airspace. Traffic information provided by an AGCS radio
station operator is therefore based primarily on reports made by other pilots.
Information provided by an AGCS radio station operator may be used to assist a pilot
in making decisions, however, the safe conduct of the flight remains the pilot’s
responsibility.

5.3 Air/Ground Station Identification
Radio operators must ensure that the full callsign, including the suffix ‘RADIO’, is

used in response to the initial call from an aircraft and on any other occasion that there
is doubt.

5.4 Phraseology and Examples

5.4.1 From time to time air traffic controllers and flight information service officers are
invited by aerodrome authorities to provide an Air/Ground Communication Service.
They are permitted to do so in certain circumstances provided they hold a valid
Certificate of Competence (CA 1308). However, air traffic controllers, in particular,
must appreciate that there is a considerable difference between the service they
normally provide and the Air/Ground Communication Service. Therefore they must be
careful not to lapse into providing an air traffic control service.

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