IAMSAR ManualINTERNATIONAL AERONAUTICAL AND

MARITIME SEARCH AND RESCUE MANUAL

Volume II

MISSION CO-ORDINATION

2007 Edition

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IMO/ICAOLondon/Montréal, 2007

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IAMSAR ManualINTERNATIONAL AERONAUTICAL AND

MARITIME SEARCH AND RESCUE MANUAL

Volume II

MISSION CO-ORDINATION

2007 Edition

incorporating 2001, 2002, 2003, 2004,

2005 and 2006 amendments

IMO/ICAOLondon/Montréal, 2007

Doc 9731-AN/958

Published jointly in 2007 by the INTERNATIONAL MARITIME ORGANIZATION

4 Albert Embankment, London SE1 7SR, United Kingdom and the

INTERNATIONAL CIVIL AVIATION ORGANIZATION 999 University Street, Montréal, Quebec, Canada H3C 5H7

First edition 1999 Second edition 2006

Third edition 2007

This edition printed in Canada by ICAO

ISBN 92-9194-925-6

ICAO PUBLICATION

ICAO sales number: 9731P2

Copyright © IMO/ICAO 2007

All rights reserved. No part of this publication may be reproduced,

stored in a retrieval system or transmitted in any form or by any means,

without prior permission in writing from the International Maritime Organization or

the International Civil Aviation Organization.

Foreword

The primary purpose of the three volumes of the International Aeronautical and Maritime Search and Rescue Manual isto assist States in meeting their own search and rescue (SAR) needs, and the obligations they accepted under theConvention on International Civil Aviation, the International Convention on Maritime Search and Rescue, and theInternational Convention for the Safety of Life at Sea (SOLAS). These volumes provide guidelines for a common aviationand maritime approach to organizing and providing SAR services. States are encouraged to develop and improve theirSAR services, co-operate with neighbouring States, and to consider their SAR services to be part of a global SAR system.

Each IAMSAR Manual volume is written with specific SAR system duties in mind, and can be used as a stand-alonedocument, or, in conjunction with the other two Volumes, as a means to attain a full view of the SAR system.

The Organization and Management volume (volume I) discusses the global SAR system concept, establishment andimprovement of national and regional SAR systems, and co-operation with neighbouring States to provide effectiveand economical SAR services;

The Mission Co-ordination volume (volume II) assists personnel who plan and co-ordinate SAR operations andexercises; and

The Mobile Facilities volume (volume III) is intended to be carried aboard rescue units, aircraft, and vessels to helpwith performance of a search, rescue, or on-scene co-ordinator functions, and with aspects of SAR that pertain totheir own emergencies.

This Manual is published jointly by the International Civil Aviation Organization and the International MaritimeOrganization. It has been updated from the first edition by including the amendments that were adopted by theseventy-fourth session of the IMO Maritime Safety Committee in June 2001 (which entered into force on1 July 2002), amendments adopted by the seventy-fifth session in May 2002 (which apply as from 1 July 2003),amendments adopted by the seventy-seventh session in June 2003 (which apply as from 1 July 2004), amendmentsadopted by the seventy-eighth session in February 2004 (which apply as from 1 July 2005), amendments adoptedby the eightieth session in May 2005 (which apply as from 1 June 2006) and amendments adopted by the eighty-firstsession in May 2006 (which apply as from June 2007).

Mission Co-ordination

Chapter 1 presents an overview of the SAR system concept, including what is involved in providing SAR services,and why such services are required and beneficial. The SAR system is examined from a global, regional, and nationalperspective. Key components of the SAR system, such as rescue co-ordination centres (RCCs), operational andsupport facilities and the on-scene co-ordinator (OSC), are discussed.

Chapter 2 focuses primarily on SAR communications topics. These include distress communications, emergencybeacons, communications for SAR operations and a variety of communications and safety systems related to or usedby the SAR system.

Chapter 3 introduces the five stages through which responses to SAR incidents typically progress, describes the threeemergency phases (Uncertainty, Alert, and Distress) and the first two stages (Awareness and Initial Action) in detail,and provides additional valuable guidance for the early stages of a SAR incident.

Chapter 4 contains a detailed discussion of the theory and practice of search planning. It presents a complete yetpractical application of search theory to the SAR search planning problem. It provides guidance for balancing theconflicting goals of covering large areas with limited facilities or using those facilities to achieve high probabilities ofdetection in small areas. The procedures outlined allow the search planner to determine the optimal area to searchso that the chances of success are maximized.

Chapter 5 discusses search techniques and operations, including search facility selection, assessment of searchconditions, search pattern selection for visual, electronic, night and land searches, search sub-area assignments,standard methods for designating and describing search sub-areas, planning of on-scene co-ordination, and finallycompiling all this data into an attainable search action plan.

iii

Chapter 6 describes aspects of rescue planning and operations such as logistics, modes of rescue, care anddebriefing of survivors, handling of deceased persons, and certain special requirements involving aircraft crash sites.

Chapter 7 contains guidance for emergency assistance other than SAR in which the SAR system may becomeinvolved.

Chapter 8 discusses the orderly conclusion of SAR operations. The topics covered include closing of SAR cases,suspending search operations, reopening a suspended SAR case, completing final reports, conducting performanceimprovement reviews and case studies, and archiving SAR case files.

An extensive set of appendices is provided. These contain useful information, forms, checklists, step-by-stepprocedures, worksheets, and tables and graphs appropriate for daily use by RCC staff.

iv

Foreword

Contents

Abbreviations and Acronyms ........................................................................................................ ix

Glossary ....................................................................................................................................... xv

Chapter 1 The Search and Rescue System

1.1 System Organization.............................................................................................. 1-1

1.2 SAR Co-ordination ................................................................................................. 1-1

1.3 SAR Resources ...................................................................................................... 1-4

1.4 Medical Assistance to Vessels ................................................................................ 1-5

1.5 Plans of Operation ................................................................................................ 1-6

1.6 SAR Operations Stages .......................................................................................... 1-6

1.7 Mission Documentation ......................................................................................... 1-8

1.8 Training and Exercises ............................................................................................ 1-9

1.9 Improving Professionalism...................................................................................... 1-13

1.10 Public Relations ..................................................................................................... 1-13

1.11 Computer Resources ............................................................................................. 1-15

1.12 Decision and Management Support ....................................................................... 1-17

Chapter 2 Communications

2.1 Distress Communications ....................................................................................... 2-1

2.2 Aeronautical Mobile Service................................................................................... 2-1

2.3 Maritime Radio Service .......................................................................................... 2-3

2.4 Modes of Emission ................................................................................................ 2-3

2.5 Global Maritime Distress and Safety System ........................................................... 2-4

2.6 EPIRBs and ELTs .................................................................................................... 2-5

2.7 Satellite Communications ....................................................................................... 2-6

2.8 Vessel–Aircraft Communications ............................................................................ 2-7

2.9 Survival and Emergency Radio Equipment .............................................................. 2-8

2.10 Cellular Telephones ............................................................................................... 2-9

2.11 Special Circumstances ........................................................................................... 2-10

2.12 Communications for SAR Operations ..................................................................... 2-10

2.13 Communication Equipment Identities ..................................................................... 2-11

2.14 False Alerts............................................................................................................ 2-11

2.15 SAR Data Providers ............................................................................................... 2-11

2.16 RCC and RSC Communications ............................................................................. 2-12

2.17 Maritime Radio Telex............................................................................................. 2-12

2.18 Inmarsat SafetyNET................................................................................................ 2-13

2.19 Radio Telegraph .................................................................................................... 2-14

2.20 Phonetic Alphabet and Figure Code ....................................................................... 2-14

v

2.21 Spoken Emergency Signals and Procedural Words .................................................. 2-14

2.22 On-scene Communications .................................................................................... 2-15

2.23 Electronic Positioning ............................................................................................. 2-15

2.24 Codes, Signals, and Standard Phrases ..................................................................... 2-15

2.25 First RCC............................................................................................................... 2-16

2.26 SAR Operations Communications .......................................................................... 2-17

2.27 SAR Operations Messages ..................................................................................... 2-17

2.28 GMDSS Master Plan.............................................................................................. 2-20

2.29 Supplemental Capabilities ...................................................................................... 2-20

2.30 Difficulties in Contacting Vessels ............................................................................ 2-20

2.31 Unbarring of Inmarsat SESs by RCCs ...................................................................... 2-21

2.32 Radio call signs for aircraft involved in a search and rescue operation ..................... 2-21

Chapter 3 Awareness and Initial Action

3.1 General ................................................................................................................. 3-1

3.2 SAR Stages ............................................................................................................ 3-1

3.3 Emergency Phases ................................................................................................. 3-2

3.4 Awareness Stage ................................................................................................... 3-3

3.5 Initial Action Stage................................................................................................. 3-5

3.6 Designation of the RCC or RSC Responsible for Initiating SAR Action ..................... 3-8

3.7 RCC Procedures for Requesting SAR Facilities ........................................................ 3-10

3.8 General Considerations for the SMC ...................................................................... 3-10

Chapter 4 Search Planning and Evaluation Concepts

4.1 Overview .............................................................................................................. 4-1

4.2 Evaluating the Situation.......................................................................................... 4-1

4.3 Estimating the Distress Incident Location ................................................................ 4-3

4.4 Survivor Motion After the Distress Incident............................................................. 4-6

4.5 Total Probable Error of Position.............................................................................. 4-10

4.6 Search Planning and Evaluation Factors .................................................................. 4-11

4.7 Optimal Search Effort Allocation ............................................................................ 4-21

4.8 Computer-based Search Planning Aids.................................................................... 4-35

Chapter 5 Search Techniques and Operations

5.1 Overview .............................................................................................................. 5-1

5.2 Selection of Search Facilities .................................................................................. 5-1

5.3 Assessing Search Conditions .................................................................................. 5-1

5.4 Selecting Search Patterns ....................................................................................... 5-4

5.5 Visual Search Patterns............................................................................................ 5-6

5.6 Electronic Search Patterns ...................................................................................... 5-14

5.7 Night Search Patterns ............................................................................................ 5-17

vi

Contents

5.8 Land Search Patterns ............................................................................................. 5-20

5.9 Search Object Motion ........................................................................................... 5-21

5.10 Assignment of Search Sub-Areas to Individual Facilities ........................................... 5-24

5.11 Designation and Description of Search Sub-Areas ................................................... 5-27

5.12 Planning On-Scene Co-ordination ........................................................................... 5-29

5.13 Search Action Plans ............................................................................................... 5-30

5.14 Conduct of the Search........................................................................................... 5-31

5.15 Briefings ................................................................................................................ 5-31

5.16 Aircraft Search Procedures ..................................................................................... 5-32

5.17 Surface Facility Search Procedures ......................................................................... 5-33

5.18 Search by Land Facilities ........................................................................................ 5-33

5.19 Debriefing of Search Personnel .............................................................................. 5-33

5.20 Continuation of Search .......................................................................................... 5-33

Chapter 6 Rescue Planning and Operations

6.1 General ................................................................................................................. 6-1

6.2 Sighting and Subsequent Procedures ...................................................................... 6-2

6.3 Delivery of Rescue Personnel and Equipment ......................................................... 6-2

6.4 Supplies and Survival Equipment ............................................................................ 6-3

6.5 Supply Dropping ................................................................................................... 6-4

6.6 Medical Personnel ................................................................................................. 6-5

6.7 Rescue by Aircraft ................................................................................................. 6-5

6.8 Rescue by Maritime Facilities ................................................................................. 6-6

6.9 Rescue by Land Facilities ....................................................................................... 6-7

6.10 Use of Pararescue Teams....................................................................................... 6-7

6.11 Special Requirements at Aircraft Crash Sites ........................................................... 6-8

6.12 Ditching Assistance................................................................................................ 6-8

6.13 Rescue of Persons from Inside Damaged, Capsized, or Ditched Craft...................... 6-9

6.14 Underwater Search and Rescue ............................................................................. 6-13

6.15 Mass Rescue Operations ....................................................................................... 6-14

6.16 Care of Survivors ................................................................................................... 6-21

6.17 Debriefing of Survivors........................................................................................... 6-22

6.18 Handling of Deceased Persons............................................................................... 6-22

6.19 Critical Incident Stress............................................................................................ 6-23

6.20 Termination of Rescue ........................................................................................... 6-24

Chapter 7 Emergency Assistance other than Search and Rescue

7.1 General ................................................................................................................. 7-1

7.2 Intercept and Escort Services.................................................................................. 7-1

7.3 Safety Information ................................................................................................. 7-3

vii

Contents

7.4 Unlawful Acts ........................................................................................................ 7-3

7.5 Search and Rescue Outside of RCC Responsible Areas........................................... 7-3

7.6 Assistance to Property ........................................................................................... 7-3

7.7 Aerodrome Emergency Plan................................................................................... 7-4

Chapter 8 Conclusion of SAR Operations

8.1 General ................................................................................................................. 8-1

8.2 Closing a SAR Case ............................................................................................... 8-1

8.3 Suspending Search Operations............................................................................... 8-1

8.4 Reopening a Suspended Case ................................................................................ 8-2

8.5 Final Reports ......................................................................................................... 8-3

8.6 Performance Improvement..................................................................................... 8-3

8.7 Case Studies.......................................................................................................... 8-3

8.8 Archiving Case Files ............................................................................................... 8-4

8.9 Incident Debriefings............................................................................................... 8-4

Appendices

Appendix A Distress Communications

Appendix B Message Formats

Appendix C Mass Rescue Operations: Exercises; Industry Roles and Incident Management

Appendix D Uncertainty Phase Data

Appendix E Alert Phase Data

Appendix F Distress Phase Checklist

Appendix G Facilities and Equipment Selection

Appendix H Operation Briefing and Tasking Forms

Appendix I SITREPs and Codes

Appendix J Intercepts

Appendix K Determining Datum

Appendix L Search Planning and Evaluation Worksheets

Appendix M Preparing Initial Probability Maps

Appendix N Tables and Graphs

Appendix O Ship Reporting Systems for SAR

Appendix P Functional Characteristics to Consider with Computer-based Search Planning Aids

Appendix Q Sample Problem

Index

viii

Contents

Abbreviations and Acronyms

A ................................................................................................................................................ search area

A/C ....................................................................................................................................................... aircraft

ACC ..................................................................................................................................... area control centre

ACO .................................................................................................................................... aircraft co-ordinator

AES ............................................................................................................................ aeronautical earth station

AFN .......................................................................................................................... aeronautical fixed network

AFTN .......................................................................................... aeronautical fixed telecommunications network

AIP ........................................................................................................... Aeronautical Information Publication

AIS ................................................................................................................ aeronautical information services

AM .................................................................................................................................amplitude modulation

AMS ......................................................................................................................... aeronautical mobile service

AMS(R)S ........................................................................................... aeronautical mobile satellite (route) service

AMSS .......................................................................................................... aeronautical mobile satellite service

Amver................................................................................................ automated mutual-assistance vessel rescue

ANC .........................................................................................................................Air Navigation Commission

ARCC ................................................................................................... aeronautical rescue co-ordination centre

ARSC ................................................................................................................... aeronautical rescue sub-centre

ASW .................................................................................................................................. average surface wind

ASWe ........................................................................................................................ average surface wind error

ASWDVe ............................................................................................................ drift velocity error due to ASWe

ATC ......................................................................................................................................... air traffic control

ATN ................................................................................................... aeronautical telecommunications network

ATS ........................................................................................................................................ air traffic services

C .......................................................................................................................................... coverage factor

C/C ...............................................................................................................................................cabin cruiser

CES ...................................................................................................................................... coast earth station

CIRM.......................................................................................................... Centro Internazionale Radio-Medico

Cospas......................................................................................... Space System for Search of Vessels in Distress

CRS ...................................................................................................................................... coast radio station

C/S ......................................................................................................................................................call sign

CS ....................................................................................................................................creeping line search

CSC ............................................................................................................... creeping line search, co-ordinated

CSP ............................................................................................................................. commence search point

CW ........................................................................................................................................ continuous wave

D .................................................................................................................................................... total drift

De ............................................................................................................................................ total drift error

DD ...................................................................................................................... (leeway) divergence distance

ix

DF ......................................................................................................................................... direction finding

DMB ................................................................................................................................... datum marker buoy

DME .................................................................................................................... distance-measuring equipment

DRU ....................................................................................................................................... desert rescue unit

DSC ................................................................................................................................ digital selective calling

DVe ............................................................................................................................... total drift velocity error

E ................................................................................................................... total probable error of position

EGC .............................................................................................................................. enhanced group calling

ELR ...............................................................................................................................extra-long-range aircraft

ELT .....................................................................................................................emergency locator transmitter

ENID ...................................................................................................................................... enhanced identity

EPIRB .............................................................................................. emergency position-indicating radio beacon

ETA ............................................................................................................................. estimated time of arrival

ETD ........................................................................................................................ estimated time of departure

F/V .............................................................................................................................................. fishing vessel

FIC .............................................................................................................................. flight information centre

FIR .............................................................................................................................. flight information region

FLAR.................................................................................................................... forward-looking airborne radar

FLIR .............................................................................................................................. forward-looking infrared

FM ................................................................................................................................. frequency modulation

fs .................................................................................................................................. optimal search factor

fv ....................................................................................................... search facility velocity correction factor

fw ............................................................................................................................weather correction factor

fZ ................................................................................................................................................ effort factor

GES ................................................................................................................................... ground earth station

GHz .................................................................................................................................................... gigahertz

GLONASS.........................................................................................Global Orbiting Navigation Satellite System

GMDSS ..................................................................................................Global Maritime Distress Safety System

GNSS................................................................................................................global navigation satellite system

GPS ............................................................................................................................ global positioning system

GS ............................................................................................................................................. ground speed

gt .............................................................................................................................................gross tonnage

HEL-H ....................................................................................................................................... heavy helicopter

HEL-L .......................................................................................................................................... light helicopter

HEL-M .................................................................................................................................. medium helicopter

HF ........................................................................................................................................... high frequency

HQ .............................................................................................................................................. headquarters

I/B ...................................................................................................................................................... inboard

ICAO ..................................................................................................... International Civil Aviation Organization

x

Abbreviations and Acronyms

ICS .......................................................................................................................... incident command system

IFR ................................................................................................................................. instrument flight rules

ILS ........................................................................................................................... instrument landing system

IMC .......................................................................................................... instrument meteorological conditions

IMO ............................................................................................................ International Maritime Organization

IMSO ................................................................................................ International Mobile Satellite Organization

Inmarsat ....................................................................... satellite communication service provider for the GMDSS

INS ............................................................................................................................ inertial navigation system

INTERCO............................................................................................................... International Code of Signals

IP ............................................................................................................................................. initial position

ITU ...................................................................................................... International Telecommunication Union

JRCC ...................................................................... joint (aeronautical and maritime) rescue co-ordination centre

JRSC ................................................................................................................................ joint rescue sub-centre

kHz ..................................................................................................................................................... kilohertz

km .................................................................................................................................................. kilometres

kt ..................................................................................................................... knot (nautical miles per hour)

l ................................................................................................................................ search sub-area length

L ........................................................................................................................................................ length

Lb ..........................................................................................................................................datum base line

LCB .............................................................................................................................. line of constant bearing

LES ........................................................................................................................................ land earth station

LKP .....................................................................................................................................last known position

LOP ........................................................................................................................................... line of position

Loran ....................................................................................................................... long-range aid to navigation

LRG ....................................................................................................................................... long-range aircraft

LSB ......................................................................................................................................... lower side band

LUT ...................................................................................................................................... local user terminal

LW ....................................................................................................................................................... leeway

LWe ............................................................................................................................................... leeway error

m ....................................................................................................................................................... metres

M/V ..........................................................................................................................................merchant vessel

MCC................................................................................................................................ mission control centre

MCW............................................................................................................................. modulated carrier wave

MEDEVAC ............................................................................................................................medical evacuation

MEDICO ...........................................................................................................medical advice, usually by radio

MF ..................................................................................................................................... medium frequency

MHz ..................................................................................................................................................megahertz

MMSI ................................................................................................................maritime mobile service identity

MRCC ....................................................................................................... maritime rescue co-ordination centre

xi

Abbreviations and Acronyms

MRG ................................................................................................................................ medium-range aircraft

MRO ............................................................................................................................... mass rescue operation

MRSC ....................................................................................................................... maritime rescue sub-centre

MRU .................................................................................................................................mountain rescue unit

MSI .........................................................................................................................maritime safety information

n .............................................................................................................. number of required track spacings

N ..............................................................................................................................number of SAR facilities

NATO ............................................................................................................North Atlantic Treaty Organization

NBDP ....................................................................................................................... narrow-band direct printing

NM ...............................................................................................................................................nautical mile

NOTAM.................................................................................................................................... notice to airmen

NVG .................................................................................................................................... night vision goggles

O/B .................................................................................................................................................... outboard

O/S .................................................................................................................................................... on-scene

OS ........................................................................................................................................... contour search

OSC ................................................................................................................................. on-scene co-ordinator

OSV ................................................................................................................................. offshore supply vessel

P/C ............................................................................................................................................. pleasure craft

PIW .......................................................................................................................................... person in water

PLB ............................................................................................................................. personal locator beacon

POB ....................................................................................................................................... persons on board

POC .......................................................................................................................... probability of containment

POD ...............................................................................................................................probability of detection

POS ................................................................................................................................. probability of success

POSc................................................................................................................ cumulative probability of success

PRU ................................................................................................................................. parachute rescue unit

PS ................................................................................................................................. parallel sweep search

R .................................................................................................................................. search radius (actual)

Ro ..................................................................................................................................optimal search radius

R&D .......................................................................................................................... research and development

RANP ....................................................................................................................... regional air navigation plan

RB ................................................................................................................................................ rescue boat

RC ............................................................................................................................................... river current

RCC ......................................................................................................................... rescue co-ordination centre

RF .......................................................................................................................................... radio frequency

RSC ....................................................................................................................................... rescue sub-centre

RTG ......................................................................................................................................... radio telegraphy

RV .............................................................................................................................................. rescue vessel

S/S ..................................................................................................................................................steam ship

xii

Abbreviations and Acronyms

S/V ...............................................................................................................................................sailing vessel

S .............................................................................................................................................. track spacing

SAR ...................................................................................................................................... search and rescue

Sarsat ............................................................................................... Search and Rescue Satellite-Aided Tracking

SART .................................................................................................................. search and rescue transponder

SC ................................................................................................................... search and rescue co-ordinator

SC ................................................................................................................................................. sea current

SCe .........................................................................................................................................sea current error

SDP ................................................................................................................. search and rescue data provider

SES ........................................................................................................................................ ship earth station

SITREP ........................................................................................................................................ situation report

SMC ....................................................................................................... search and rescue mission co-ordinator

SOA ....................................................................................................................................... speed of advance

SOLAS ................................................................................................................................. Safety of Life at Sea

SPOC ........................................................................................................... search and rescue point of contact

SR .......................................................................................................................................... separation ratio

SRG ...................................................................................................................................... short-range aircraft

SRR ............................................................................................................................ search and rescue region

SRS ...................................................................................................................... search and rescue sub-region

SRU ................................................................................................................................search and rescue unit

SS ............................................................................................................................ expanding square search

SSB .......................................................................................................................................... single side-band

SU ................................................................................................................................................. search unit

SUBSAR ................................................................................................................. submarine search and rescue

SURPIC ...................................................................................................................................... surface picture

T .................................................................................................................................. search time available

T/V ................................................................................................................................................. tank vessel

TAS ............................................................................................................................................. true air speed

TC ................................................................................................................................................tidal current

TCe ....................................................................................................................................... tidal current error

TCA .............................................................................................................................time of closest approach

TFR .......................................................................................................................... temporary flight restriction

TLX .......................................................................................................................................................... telex

TSN ........................................................................................................................ track line search, non-return

TSR .............................................................................................................................. track line search, return

TWC ...................................................................................................................................... total water current

TWCe ............................................................................................................................ total water current error

U ................................................................................................................................................ wind speed

UHF ....................................................................................................................................ultra high frequency

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Abbreviations and Acronyms

UIR .................................................................................................................... upper flight information region

ULR ............................................................................................................................... ultra-long-range aircraft

USAR............................................................................................................................urban search and rescue

USB ......................................................................................................................................... upper side-band

UTC ......................................................................................................................... co-ordinated universal time

UTM ............................................................................................................... universal transverse Mercator grid

v ............................................................................................................................... speed of search object

V ........................................................................................................................... SAR facility ground speed

VFR ......................................................................................................................................... visual flight rules

VHF .................................................................................................................................... very high frequency

VLR ................................................................................................................................very-long-range aircraft

VMC..................................................................................................................visual meteorological conditions

VOR .................................................................................................................VHF omnidirectional radio range

VS .............................................................................................................................................. sector search

w ................................................................................................................................. search sub-area width

W ...............................................................................................................................................sweep width

WC ...............................................................................................................................................wind current

WCe ...................................................................................................................................... wind current error

WMO .......................................................................................................... World Meteorological Organization

Wu ........................................................................................................................... uncorrected sweep width

X ..................................................................................................................................... initial position error

Y ............................................................................................................................SAR facility position error

Z ............................................................................................................................................... search effort

Za ................................................................................................................................. available datum effort

Zr .............................................................................................................................................. relative effort

Zrc ............................................................................................................................ cumulative relative effort

Zta ......................................................................................................................... total available search effort

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Abbreviations and Acronyms

Glossary

Aircraft Co-ordinator (ACO) A person or team who co-ordinates the involvement of multiple aircraftSAR operations in support of the SAR mission co-ordinator and on-scene

co-ordinator.

Aeronautical drift (Da) Drift caused by bailout trajectory or aircraft gliding distance.

Aeronautical position Initial position of a distressed aircraft at the time of re-entry, engine failure,aircrew ejection or bailout.

Aircraft glide Maximum ground distance an aircraft could cover during descent.

Alert Phase A situation wherein apprehension exists as to the safety of an aircraft or marinevessel, and of the persons on board.

Alerting post Any facility intended to serve as an intermediary between a person reportingan emergency and a rescue co-ordination centre or rescue sub-centre.

Amver A world-wide ship reporting system for search and rescue.

Available datum effort (Za) The amount of effort available for assignment to a particular datum.

Awareness range Distance at which a search scanner can first detect something different from itssurroundings but not yet recognize it.

Awareness stage A period during which the SAR system becomes aware of an actual orpotential incident.

Captain Master of a ship or pilot-in-command of an aircraft, commanding officer of awarship or an operator of any other vessel.

Checksum digit A digit which is appended to a numeric data element and used to verify itsaccuracy. Checksum digits are computed by adding the digits of the data

element.

Coast earth station (CES) Maritime name for an Inmarsat shore-based station linking ship earth stationswith terrestrial communications networks.

Commence search point (CSP) Point normally specified by the SMC where a SAR facility is to begin its searchpattern.

Conclusion stage A period during a SAR incident when SAR facilities return to their regularlocation and prepare for another mission.

Co-ordinated search pattern Multi-unit pattern using vessel(s) and aircraft.

Co-ordinated universal time (UTC) International term for time at the prime meridian.

Cospas–Sarsat System A satellite system designed to detect distress beacons transmitting on thefrequencies 121.5 MHz and 406 MHz.

Course The intended horizontal direction of travel of a craft.

Coverage factor (C) The ratio of the search effort (Z) to the area searched (A). C = Z/A. For parallelsweep searches, it may be computed as the ratio of sweep width (W) to track

spacing (S). C = W/S.

xv

Craft Any air or sea-surface vehicle, or submersible of any kind or size.

Cumulative probabilityof success (POSc)

The accumulated probability of finding the search object with all the search

effort expended over all searches to date. POSc is the sum of all individual

search POS values.

Cumulative relative effort (Zrc) The sum of all previous relative efforts plus the relative effort for the next plannedsearch effort. This value determines the optimal search factor. Zrc = Zr-1 + Zr-2 +

Zr-3 +...+ Zr-next search

Datum A geographic point, line, or area used as a reference in search planning.

Datum area Area in where it is estimated that the search object is most likely to be located.

Datum base line That portion of a datum line that is drawn between two specific locations, suchas way points on a distressed or missing craft’s intended track line. May be

extended to form a datum line that accounts for the probable error(s) of one or

both locations.

Datum line A line, such as the distressed craft’s intended track line or a line of bearing,which defines the centre of the area where it is estimated that the search

object is most likely to be located.

Datum marker buoy (DMB) Droppable floating beacon used to determine actual total water current, or toserve as a location reference.

Datum point A point, such as a reported or estimated position, at the centre of the areawhere it is estimated that the search object is most likely to be located.

Dead reckoning (DR) Determination of position of a craft by adding to the last fix the craft’s courseand speed for a given time.

Digital selective calling (DSC) A technique using digital codes which enables a radio station to establishcontact with, and transfer information to, another station or group of stations.

Direction of current Direction toward which a current is flowing. Also called ‘‘set’’.

Direction of waves, swell or seas Direction from which the waves, swells, or seas are moving.

Direction of wind Direction from which the wind is blowing.

Distress Phase A situation wherein there is reasonable certainty that a vessel or other craft,including an aircraft or a person, is threatened by grave and imminent danger

and requires immediate assistance.

Ditching The forced landing of an aircraft on water.

Divergence distance Distance between the left and right leeway divergence datums.

Drift The movement of a search object caused by environmental forces.

Drift error (De) See Total probable drift error.

Effort factor (fZ) (1) For point and leeway divergence datums, the effort factor is the square ofthe total probable error of position (E). fZp = E

2.

(2) For line datums, the effort factor is the product of the total probable error of

position (E) and the length of the line (L). fZl = E 6 L.

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Glossary

Emergency Phase A generic term meaning, as the case may be, uncertainty phase, alert phase, ordistress phase.

False alarm Distress alert initiated for other than an appropriate test, by communicationsequipment intended for alerting, when no distress situation actually exists.

False alert Distress alert received from any source, including communications equipmentintended for alerting, when no distress situation actually exists, and a

notification of distress should not have resulted.

Fetch The distance over which the wind blows in a constant direction, withoutobstruction.

First RCC RCC affiliated with the shore station that first acknowledges a distress alert,and which should assume responsibility for all subsequent SAR co-ordination

unless and until responsibility is accepted by another RCC better able to take

action.

Fix A geographical position determined by visual reference to the surface,referencing to one or more radio navigation aids, celestial plotting, or other

navigation device.

Forward-looking airborneradar (FLAR)

Any aircraft-mounted radar designed to detect targets on or near the ocean

surface by scanning a sector typically centred in the direction of aircraft

heading. FLAR may also perform weather avoidance/navigation in support of

aircraft operations.

Forward-looking infrared (FLIR) An imaging system, mounted on board surface vessels or aircraft, designed todetect thermal energy (heat) emitted by targets and convert it into a visual

display.

General communications Operational and public correspondence traffic other than distress, urgencyand safety messages, transmitted or received by radio.

Global Maritime Distressand Safety System (GMDSS)

A global communications service based upon automated systems, both

satellite-based and terrestrial, to provide distress alerting and promulgation of

maritime safety information for mariners.

Global Navigation SatelliteSystem (GNSS)

World-wide position and time determination system that includes one or more

satellite constellations and receivers.

Grid Any set of intersecting perpendicular lines spaced at regular intervals.

Grid cell A square or rectangular area formed by pairs of adjacent, perpendicular gridlines.

Ground speed (GS) The speed an aircraft is making relative to the earth’s surface.

Heading The horizontal direction in which a craft is pointed.

Hypothermia Abnormal lowering of internal body temperature (heat loss) from exposure tocold air, wind, or water.

Indicated air speed (IAS) The aircraft speed shown on the air speed indicator gauge. IAS corrected forinstrument error and atmospheric density equals true air speed.

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Glossary

Initial action stage A period during which preliminary action is taken to alert SAR facilities andobtain amplifying information.

Initial position error (X) The estimated probable error of the initial position(s) at the beginning of a driftinterval. For the first drift interval, this will be the probable error of the initially

reported or estimated position of the SAR incident. For subsequent drift

intervals, it will be the total probable error of the previous datum position(s).

Inmarsat A system of geostationary satellites for world-wide mobile communicationsservices, and which support the Global Maritime Distress and Safety System

and other emergency communications systems.

Instrument flight rules (IFR) Rules governing the procedures for conducting instrument flight. Also a termused by pilots and controllers to indicate type of flight plan.

Instrument meteorologicalconditions (IMC)

Meteorological conditions expressed in terms of visibility, distance from cloud,

and ceiling less than the minima specified for visual meteorological conditions.

Joint rescue co-ordinationcentre (JRCC)

A rescue co-ordination centre responsible for both aeronautical and maritime

search and rescue incidents.

Knot (kt) A unit of speed equal to one nautical mile per hour.

Last known position (LKP) Last witnessed, reported, or computed DR position of a distressed craft.

Leeway (LW) The movement of a search object through water caused by winds blowingagainst exposed surfaces.

Leeway divergence angle The average angle between an object’s direction of leeway and the downwinddirection. Leeway may diverge to either the right or the left of the downwind

direction. Current evidence indicates that objects with significant leeway

divergence angles rarely jibe or tack downwind.

Leeway error (LWe) The probable error of the leeway estimate.

Local user terminal (LUT) An earth receiving station that receives beacon signals relayed by Cospas–Sarsat satellites, processes them to determine the location of the beacons, and

forwards the signals.

Mass Rescue Operation (MRO) Search and rescue services characterized by the need for immediate responseto large numbers of persons in distress, such that the capabilities normally

available to search and rescue authorities are inadequate.

MAYDAY The international radiotelephony distress signal, repeated three times.

MEDEVAC Evacuation of a person for medical reasons.

MEDICO Medical advice. Exchange of medical information and recommendedtreatment for sick or injured persons where treatment cannot be administered

directly by prescribing medical personnel.

Meteorological visibility The maximum range at which a large object, such as land masses ormountains, can be seen. Also referred to as Meteorological Range.

Mission control centre (MCC) Part of the Cospas–Sarsat system that accepts alert messages from the local userterminal(s) and other mission control centres to distribute to the appropriate

rescue co-ordination centres or other search and rescue points of contact.

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Glossary

Narrow-Band DirectPrinting (NBDP)

Automated telegraphy, as used by the NAVTEX system and telex-over-radio.

NAVAREA One of 16 areas into which the world’s oceans are divided by the InternationalMaritime Organization for dissemination of navigation and meteorological

warnings.

NAVTEX The system for the broadcast and automatic reception of maritime safetyinformation by means of narrow-band direct-printing telegraphy.

On-scene The search area or the actual distress site.

On-scene co-ordinator (OSC) A person designated to co-ordinate search and rescue operations within aspecified area.

On-scene endurance The amount of time a facility may spend at the scene engaged in search andrescue activities.

Operations stage A period during a SAR incident when SAR facilities proceed to the scene,conduct search, rescue survivors, assist distressed craft, provide emergency

care for survivors, and deliver survivors to a suitable facility.

Optimal search area The search area which will produce the highest probability of success whensearched uniformly with the search effort available.

Optimal search factor (fs) A value, based on the amount of relative effort available, which is used toestimate the optimal area to search so the chances of finding the search object

are maximized. (see Optimal search radius).

Optimal search plan A plan that maximizes the probability of success of finding the search objectusing the available search effort.

Optimal search radius One-half the width of the optimal search area. Optimal search radius iscomputed as the product of the total probable error of position (E) and the

optimal search factor (fs). Ro = E 6 fs.

Overdue A situation where a craft has failed to arrive at its intended destination whenexpected and remains missing.

PAN-PAN The international radiotelephony urgency signal. When repeated three times,indicates uncertainty or alert, followed by nature of urgency.

Personal Locator Beacon (PLB) Personal radio distress beacon for alerting and transmitting homing signals.

Pilot-in-command The pilot responsible for the operation and safety of the aircraft during flighttime.

Planning stage A period during a SAR incident when an effective plan of operations isdeveloped.

Position A geographical location normally expressed in degrees and minutes of latitudeand longitude.

Positioning Process of determining a position which can serve as a geographical referencefor conducting a search.

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Glossary

Possibility area (1) The smallest area containing all possible survivor or search object locations.(2) For a scenario, the possibility area is the smallest area containing all

possible survivor or search object locations which are consistent with the facts

and assumptions used to form the scenario.

Primary swell The swell system having the greatest height from trough to crest.

Probability of containment (POC) The probability that the search object is contained within the boundaries of anarea, sub-area, or grid cell.

Probability of detection (POD) The probability of the search object being detected, assuming it was in theareas that were searched. POD is a function of coverage factor, sensor, search

conditions and the accuracy with which the search facility navigates its

assigned search pattern. Measures sensor effectiveness under the prevailing

search conditions.

Probability of success (POS) The probability of finding the search object with a particular search. For eachsub-area searched, POS = POC 6 POD. Measures search effectiveness.

Probability map A set of grid cells covering a scenario’s possibility area where each grid cell islabelled with the probability of the search object being in that grid cell. That is,

each grid cell is labelled with its own POC value.

Probable error (from statistics) The range on either side of the average or expected value such that theprobability of being within that range is 50%.

Relative effort (Zr) The amount of available search effort (Z) divided by the effort factor. Therelative effort relates the size of the effort available for a particular search to

the size of the search object’s location probability distribution at the time of

the search. Zr = Z/fZ.

Rescue An operation to retrieve persons in distress, provide for their initial medical orother needs, and deliver them to a place of safety.

Rescue co-ordination centre (RCC) A unit responsible for promoting efficient organization of search and rescueservices and for co-ordinating the conduct of search and rescue operations

within a search and rescue region. Note: The term RCC will be used within this

Manual to apply to either aeronautical or maritime centres; ARCC or MRCC will

be used as the context warrants.

Rescue sub-centre (RSC) A unit subordinate to a rescue co-ordination centre, established tocomplement the latter according to particular provisions of the responsible

authorities. Note: The term RSC will be used within this Manual except where it

applies only to aeronautical or maritime; then ARSC or MRSC will be used.

Rhumb line Straight line between two points on a Mercator projection chart.

SafetyNET A service of Inmarsat enhanced group call (EGC) system specifically designedfor promulgation of maritime safety information (MSI) as a part of the Global

Maritime Distress and Safety System (GMDSS).

SarNET A broadcast system between RCCs within the footprint of an individualsatellite.

Scenario A consistent set of known facts and assumptions describing what may havehappened to the survivors.

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Glossary

Sea Condition of the surface resulting from waves and swells.

Sea current (SC) The residual current when currents caused by tides and local winds aresubtracted from local current. It is the main, large-scale flow of ocean waters.

Sea current error (SCe) The probable error of the sea current estimate.

Search An operation, normally co-ordinated by a rescue co-ordination centre orrescue sub-centre, using available personnel and facilities to locate persons in

distress.

Search action plan Message, normally developed by the SMC, for passing instructions to SARfacilities and agencies participating in a SAR mission.

Search and rescue airspacereservation

Temporary airspace reservation to prevent non-SAR aircraft from interfering

with SAR operations.

Search and rescue briefing officer An officer appointed, usually by the SMC, to brief departing SAR facilities anddebrief returning SAR facilities.

Search and rescue case Any potential or actual distress about which a facility opens a documentaryfile, whether or not SAR resources are dispatched.

Search and rescue co-ordinatingcommunications

Communications necessary for the co-ordination of facilities participating in a

search and rescue operation.

Search and rescueco-ordinator (SC)

One or more persons or agencies within an Administration with overall

responsibility for establishing and providing SAR services, and ensuring that

planning for those services is properly co-ordinated.

Search and rescuedata provider (SDP)

A source for a rescue co-ordination centre to contact to obtain data to support

search and rescue operations, including emergency information from

communications equipment registration databases, ship reporting systems,

and environmental data systems (e.g., weather or sea current).

Search and rescue facility Any mobile resource, including designated search and rescue units, used toconduct search and rescue operations.

Search and rescue incident Any situation requiring notification and alerting of the SAR system and whichmay require SAR operations.

Search and rescue liaison officer An officer assigned to promote co-ordination during a SAR mission.

Search and rescue missionco-ordinator (SMC)

The official temporarily assigned to co-ordinate response to an actual or

apparent distress situation.

Search and rescue plan A general term used to describe documents which exist at all levels of thenational and international search and rescue structure to describe goals,

arrangements, and procedures which support the provision of search and

rescue services.

Search and rescue pointof contact (SPOC)

Rescue co-ordination centres and other established and recognized national

points of contact which can accept responsibility to receive Cospas–Sarsat

alert data to enable the rescue of persons in distress.

Search and rescue region (SRR) An area of defined dimensions, associated with a rescue co-ordination centre,within which search and rescue services are provided.

xxi

Glossary

Search and rescue service The performance of distress monitoring, communication, co-ordination andsearch and rescue functions, including provision of medical advice, initial medical

assistance, or medical evacuation, through the use of public and private

resources, including co-operating aircraft, vessels and other craft and installations.

Search and rescue stage Typical steps in the orderly progression of SAR missions. These are normallyAwareness, Initial Action, Planning, Operations, and Mission Conclusion.

Search and rescuesub-region (SRS)

A specified area within a search and rescue region associated with a rescue

sub-centre.

Search and rescue unit (SRU) A unit composed of trained personnel and provided with equipment suitablefor the expeditious conduct of search and rescue operations.

Search area The area, determined by the search planner, that is to be searched. This areamay be sub-divided into search sub-areas for the purpose of assigning specific

responsibilities to the available search facilities.

Search effort (Z) A measure of the area a search facility can effectively search within the limits ofsearch speed, endurance, and sweep width. Search effort is computed as the

product of search speed (V), search endurance (T), and sweep width (W).

Z = V 6 T 6 W.

Search endurance (T) The amount of ‘‘productive’’ search time available at the scene. This figure isusually taken to be 85% of the on-scene endurance, leaving a 15% allowance

for investigating sightings and navigating turns at the ends of search legs.

Search facility position error (Y) Probable error in a search craft’s position, based on its navigationalcapabilities.

Search object A ship, aircraft, or other craft missing or in distress or survivors or relatedsearch objects or evidence for which a search is being conducted.

Search pattern A track line or procedure assigned to an SRU for searching a specified area.

Search radius The actual search radius used to plan the search and to assign search facilities.It is usually based on adjustments to the optimal search radius that are needed

for operational reasons.

Search speed (V) The speed (or velocity) with which a search facility moves over the groundwhen searching.

Search sub-area A designated area to be searched by a specific assigned search facility orpossibly two facilities working together in close co-ordination.

Secondary swells Swell systems of less height than the primary swell.

Sensors Human senses (sight, hearing, touch, etc.), those of specially trained animals(such as dogs), or electronic devices used to detect the object of a search.

Separation ratio (SR) The ratio of the divergence distance (DD) between two leeway divergencedatums to the total probable error of position (E). (SR = DD/E).

Set Direction towards which a current flows

Situation report (SITREP) Reports, from the OSC to the SMC or the SMC to interested agencies, to keepthem informed of on-scene conditions and mission progress.

xxii

Glossary

Sortie Individual movement of a resource in conducting a search or renderingassistance.

Surface drift Vector sum of total water current and leeway. Sometimes called Total Drift.

Surface picture (SURPIC) A list or graphic display from a ship reporting system of information aboutvessels in the vicinity of a distress situation that may be called upon to render

assistance.

Surface position The position of the search object on the earth’s surface at the time of initialdistress, or its first contact with the earth’s surface.

Sweep width (W) A measure of the effectiveness with which a particular sensor can detect aparticular object under specific environmental conditions.

Swell Condition of the surface caused by a distant wind system. The individual swellappears to be regular and smooth with considerable distance between

rounded crests.

Swell direction The direction from which a swell is moving. The direction toward which a swellis moving is called the down swell direction.

Swell face The side of the swell toward the observer. The backside is the side away fromthe observer. These definitions apply regardless of the direction of swell

movement.

Swell velocity Velocity with which the swells advance with relation to a fixed reference point,measured in knots.

Tidal current (TC) Near-shore currents caused by the rise and fall of the tides.

Tidal current error (TCe) The probable error of the tidal current estimate.

Time of closest approach (TCA) Time during a satellite pass when the satellite is closest to a signal source.

Total available sear