e sub-committee on human element, htw 3/wp.6/add.3 … · 2016-05-18 · radar setting and...

https://edocs.imo.org/Final Documents/English/HTW 3-WP.6-Add.3 (E).doc

E

SUB-COMMITTEE ON HUMAN ELEMENT, TRAINING AND WATCHKEEPING 3rd session Agenda item 3

HTW 3/WP.6/Add.3

4 February 2016 Original: ENGLISH

DISCLAIMER As at its date of issue, this document, in whole or in part, is subject to consideration by the IMO organ

to which it has been submitted. Accordingly, its contents are subject to approval and amendment of a substantive and drafting nature, which may be agreed after that date.

VALIDATION OF MODEL TRAINING COURSES

Report of Drafting Group

Attached is annex 2 to the Report of Drafting Group on Validation of model training courses (HTW 3/WP.6).

***

HTW 3/WP.6/Add.3 Annex 2, page 1


ANNEX 2

DRAFT REVISED IMO MODEL COURSE ON RADAR NAVIGATION AT OPERATIONAL LEVEL

MODEL

COURSE

1.07

RADAR NAVIGATION AT OPERATIONAL LEVEL

RADAR NAVIGATION, RADAR PLOTTING AND USE OF ARPA



Contents

Contents .......................................................................................................... 2

Introduction ...................................................................................................... 5

Part A: Course Framework ............................................................................. 10

Part B: Course Outline and Timetable ............................................................ 20

Part C: Detailed Teaching Syllabus ................................................................ 29

Part D: Instructor Manual ............................................................................... 45

1 Basic theory and operational principles of marine radar systems ............. 47

Detailed teaching packages ....................................................................... 47

Assessment techniques ............................................................................. 70

Teaching guidance ..................................................................................... 71

2 Radar setting and operation in accordance with manufacturer's instructions

.................................................................................................................. 74

Detailed teaching packages ....................................................................... 74

Assessment techniques ........................................................................... 102

Teaching guidance ................................................................................... 102

3 Using radar to ensure safe navigation .................................................... 105

Detailed teaching packages ..................................................................... 105



4 Manual radar plotting .............................................................................. 124




5 ARPA system or radar target tracking (TT) and AIS reporting functions ..... 137




6 Operation of ARPA or radar target tracking (TT)

and AIS reporting functions ..................................................................... 157




7 Application of COLREGs when using radar ............................................ 188




Appendix 1 – A sample of training programme ....................................................... 197

Appendix 2 – Examples of lesson plan ................................................................... 199

Appendix 3 – An Example of lesson plan for practical training ............................... 201



Part E: Evaluation and Assessment ............................................................. 212

Appendix 4 – An example of examination paper ..................................................... 217

Appendix 5 – An example of assessment for practical training ............................... 226

Appendix 6 – Sample checklist for evaluation of proficiency in the use of

Radar and ARPA ..................................................................................................... 229

Annex 1 – Resolution MSC. 192(79) (Adopted on 6 December 2004) ................... 237

Annex 2 – GUIDELINES FOR THE PRESENTATION OF NAVIGATION-RELATED

SYMBOLS (SN.1/Circ.243/Rev.1, annex 1) ............................................................ 267

Annex 3 – GUIDANCE ON THE IMPLEMENTATION OF MODEL COURSES ....... 276



Foreword

Since its inception the International Maritime Organization has recognized ……….[To

be inserted]

K. Lim

Secretary-General



Introduction

Purpose of the model courses

The purpose of IMO model courses is to assist maritime training providers and their

teaching staff in organizing and introducing new training courses, or in enhancing,

updating or supplementing existing training materials where the quality and

effectiveness of the training courses may thereby be improved.

It is not the intention of the model course programme to present instructors with a rigid

"teaching package" which they are expected to "follow blindly". Nor is it the intention

to substitute audio-visual or "programmed" materials for the instructor's presence. As

in all training endeavours, the knowledge, skills and dedication of the instructors are

the key components in the transfer of knowledge and skills to those being trained

through IMO model course material.

Because educational systems and the cultural backgrounds of trainees in maritime

subjects vary considerably from country to country, the model course material has

been designed to identify the basic entry requirements and trainee target group for

each course in universally applicable terms, and to specify clearly the technical

content and levels of knowledge and skill necessary to meet the technical intent of

IMO conventions and related to its recommendations.

Use of the model course

To use the model course the instructor should review the course plan and detailed

syllabus, taking into account the information provided under the entry standards

specified in the course framework. The actual level of knowledge and skills and the

prior technical education of the trainees should be kept in mind during this review, and

any areas within the detailed syllabus which may cause difficulties because of

differences between the actual trainee entry level and that assumed by the course

designer should be identified. To compensate for such differences, the instructor is

expected to delete from the course, or reduce the emphasis on items dealing with

knowledge or skills already attained by the trainees. He/she should also identify any

academic knowledge, skills or technical training which they may not have acquired.

By analysing the detailed syllabus and the academic knowledge required to allow

training in the technical area to proceed, the instructor can design an appropriate

pre-entry course or, alternatively, insert the elements of academic knowledge required



to support the technical training elements concerned at appropriate points within the

technical course.

Adjustment of the course objective, scope and content may also be necessary if in

your maritime industry the trainees completing the course are to undertake duties

which differ from the course objectives specified in the model course.

Within the course outline the course designers have indicated their assessment of the

time which should be allotted to each area of learning. However, it must be

appreciated that these allocations are arbitrary and assume that the trainees have

fully met all entry requirements of the course. The instructor should therefore review

these assessments and may need to re-allocate the time required to achieve each

specific learning objective or training outcome.

Lesson plans

Having adjusted the course content to suit the trainee intake and any revision of the

course objectives, the instructor should draw up lesson plans based on the detailed

syllabus. The detailed syllabus contains specific references to the textbooks or

teaching materials proposed to be used in the course. Where no adjustment has been

found necessary in the learning objectives of the detailed syllabus, the lesson plans

may simply consist of the detailed syllabus with keywords or other reminders added to

assist the instructor in making his/her presentation of the material.

Presentation

The presentation of concepts and methodologies must be repeated in various ways

until the instructor is satisfied that the trainee has attained each specific learning

objective or training objective. The syllabus is laid out in learning objective format and

each objective specifies a required performance or, what the trainee must be able to

do as the learning or training outcome. Taken as a whole, these objectives aim to

meet the knowledge, understanding and proficiency (KUPs) specified in the

appropriate tables of the STCW Code.

Implementation

For the course to run smoothly and to be effective, considerable attention must be

paid to the availability and use of:

Properly qualified instructors

Support staff



Rooms and other spaces

Equipment

Suggested references, textbooks, technical papers

Other reference material.

Thorough preparation is the key to successful implementation of the course. IMO has

produced a booklet entitled "Guidance on the implementation of IMO model courses",

which deals with this aspect in greater detail.

Course framework

For ease of reference, this course is divided into five parts.

Part A is a general description of the model course and the conditions that are needed

for its implementation, which provides the framework for the course with its aims and

objectives and notes on the suggested teaching facilities and equipment. A list of

useful teaching aids, references and textbooks is also included.

Part B provides an outline of lectures, demonstrations and simulator exercises for the

course, together with a suggested sequence and timetable. From the teaching and

learning point of view, it is more important that the trainee achieves the minimum

standard of competence defined in the STCW Code than that a strict timetable is

followed. Depending on their experience and ability, some trainees will take longer to

become proficient in some topics than in others.

Part C gives the Detailed Teaching Syllabus. This is based on the theoretical and

practical knowledge specified in the STCW Code. It is written as a series of learning

objectives, in other words what the trainee is expected to be able to do as a result of

the teaching and training. Each of the objectives is expanded to define a required

performance of knowledge, understanding and proficiency. IMO and other references,

textbook references and suggested teaching aids are included to assist the instructor

in designing lessons.

Part D contains an Instructor Manual with additional explanations, exercises and

examples of lesson plan based on the Knowledge, Understanding and Proficiency

given in Part C. Especially, Part D also provides suggestions regarding teaching

methodologies, evaluation technique, issues arising during the training and measures

to be addressed.

Part E provides a suggestive Evaluation and Assessment Programme for training

efficiency, which aims to assist trainee learning, identify their strengths and

weaknesses, assess the effectiveness of a particular instructional strategy, evaluate

and improve the effectiveness of curriculum programmes, and teaching effectiveness.



It is worth noting that the competence evaluation standards given in Part A of the

STCW Code should be used when performing the evaluation and assessment

programme.

In order to ensure that the end users have necessary information to use in the course

development, revision, and approval process, Appendix I is provided in the model

course. The contents of this part are excerpted from publications.

To keep the training programmes up to date, the feedbacks from the model course

users are very important. This information can help to improve better training in safety

at sea and protect the marine environment. Appendix II provides a questionnaire

related to the model course and its implementation. It contains contact information as

well so that the model course users can give their valuable answers and comments.

Explanatory note

The course consists of seven main topics as follows:

Topic 1

Basic theory and operation principles of marine radar systems

Topic 2

Radar setting and operation in accordance with manufacturer's instructions

Topic 3

Using radar to ensure safe navigation

Topic 4

Manual radar plotting

Topic 5

ARPA system or radar target tracking (TT) and AIS reporting functions

Topic 6

Operation of ARPA or radar target tracking (TT) and AIS reporting functions

Topic 7

Application of the COLREGs when using radar

It is advised that the course is to be taught:

as a complete module covering all training Topics l-7; or

only as a radar position-fixing, radar navigation and manual radar plotting course

covering Topic l-4 and partial contents of Topic 7. In this case, the contents of

automatic target tracking and AIS reported targets in Topic 7 may be ignored.



This model course is consistent with the note in Table A-II/1 of the STCW Code which

states:

Training and assessment in the use of ARPA is not required for those who serve

exclusively on ships not fitted with ARPA. This limitation shall be reflected in the

endorsement issued to the seafarer concerned.

The above topics are mapped with the competencies in STCW Table A-II/1 on

page 16.

If the teaching topics do not involve radar automatic target tracking, trainees may

follow a course based on Topic 1 to 4 and Topic 7 except those sub-topics which

involve automatic target tracking and AIS reported target. If teaching topics include

radar automatic target tracking, the lectures should cover all the topics of this model

course. However, teaching Topics 5, 6 and the AIS reported target of Topic 7 may be

ignored if the ARPA course is based on the competences satisfying

IMO resolution A.823(19) and the prior versions.

Validation

The information contained in this document has been validated by the Sub-Committee

on Human Element, Training and Watchkeeping for use by technical advisers,

consultants and experts for the training and certification of seafarers so that the

minimum standards implemented may be as uniform as possible. Validation in the

context of this document means that no grounds have been found to object to its

content.

In reaching a decision in this regard, the Sub-Committee was guided by the advice of

a Validation Group comprised of representatives designated by IMO.



Part A: Course Framework

Aims

This model course aims to meet the mandatory minimum standards of competence

given in Table A-II/1 of STCW for "use of radar and ARPA to maintain safety of

navigation". The course includes the theory necessary to understand the system

configuration, principles, performance of shipborne marine radar and ARPA, the

factors affecting radar performances, how radar information is obtained, displayed

and analysed, the limitations and accuracy of that information, the correct use of

operational controls to obtain an optimal display and use radar information to maintain

safety of navigation. It aims to meet the mandatory standards in Table A-II/1 of the

STCW for "use of radar and ARPA to maintain safety of navigation".

In the design of this course, due consideration has been given to the available IMO

resolutions and guidelines on marine radar operations, including Regulations 18 and

19 in Chapter V of Safety of Life at Sea (SOLAS) Convention, Sections A-I/12

and B-I/12 of the STCW Convention and IMO Performance Standards for Radar

Equipment as amended.

Objective

A trainee successfully completing this course and meeting the required performance

standards will recognize when radar should be in use; will select a suitable mode and

range setting for the circumstances; will be able to set the controls for optimal

performance; and will be aware of the limitations of the equipment in detecting targets

and in terms of accuracy.

When within range of the coast, the trainee will be able to compare the radar display

with the chart, select suitable conspicuous land targets and use these targets to fix his

position; will be able to use radar maps, navigation lines and routes to maintain the

own ship on the planned and safe routes.

The trainee will also be able to choose an appropriate radar presentation mode; select

plotting and graphics controls suitable for the circumstances; make appropriate use of

operational alarms; acquire and track those targets which may present a potential

threat of collision; extract the information needed on course, speed and nearest

approach to enable early actions to be taken in accordance with the COLREGs to

prevent a close-quarters situation arising; and make use of radar to confirm and

monitor their actions.



The trainee will understand the dangers of over-reliance on the automatic acquisition

and tracking of targets and on operational alarms; will also be aware of the

performance standards set out in IMO Resolutions on radar performances, and

factors (including errors from sensor inputs) which may affect the accuracy of derived

information; and will realize the need to check the accuracy of inputs and the correct

functioning of the radar.

Entry standards

This course is principally intended for candidates for certification as officers in charge

of a navigational watch. Prior to entering the course, it is recommended the trainees

should have completed a minimum period of six months at sea and preferably have

gained some experience of watchkeeping.

Trainee officers for certification as officers in charge of a navigational watch should

have completed, or be following a planned and structured programme of training;

shipboard training should include tasks or projects relating to bridge work and

watchkeeping duties. Instructors may find evidence of the standard attained by

trainees in the prospective officer's training record book.

The course would also be of value to others using radar, e.g. those working in such

craft as harbour and customs patrol launches, in which case the entry standards may

be adjusted to suit the particular circumstances. However, the intake of trainees for

each course should normally have similar backgrounds.

In consideration of radar technology development, it is advised that trainee officers be

familiarized with personal computer operations, have the knowledge of planning and

conducting a passage and determining position and maintaining a safe navigational

watch related to this course in the KUP Table A-II/1 of the STCW Code, and be

proficient of such navigational aids as transmitting heading device (THD), speed and

distance measuring equipment (SDME), electronic position-fixing sytem (EPFS) and

automatic identification system (AIS).

Course certification, diploma or document

On successful completion of the course and assessments, a document may be issued

certifying that the holder has successfully completed a course of training which meets

or exceeds the level of knowledge and competence specified in Table A-II/1 of the

STCW Code.

The certification, diploma or document may be issued by the administrative authority

or its authorized institutes.



Course intake limitations

Depending on the availability of radar and radar simulator equipment, the course

intake should be limited to not more than three trainees per radar and radar simulator

display to allow each trainee sufficient practice in the operation of the equipment.

All practical demonstrated assessments must be performed independently by each

individual trainee.

Staff requirements

The instructor must have appropriate training in instructional techniques and training

methods (Section A-I/6 of the STCW Code). Those responsible for training and

competence for seafarers should be appropriately qualified in accordance with the

provisions of Section A-I/6 of the STCW Code, for the type and the level of training or

assessment involved. Depending on the complexity of the exercises set, an assistant

instructor with similar experience is desirable if more than four own ship stations are in

use for practical exercises.

Teaching facilities and equipment

The course requires a marine radar simulator with an instructor station and sufficient

own ship displays to accommodate the number of trainees.

The equipment must incorporate at least two own ship stations and must satisfy the

general performance standards for simulators used in training as mentioned in the

STCW Code A-I/12, paragraphs 1 and 2 and additioinal performance standards in

STCW Code A-I/12 paragraph 4 and 5). It must be capable of simulating the

operational capabilities of navigational radar equipment which meets all applicable

performance standards of IMO. The performance standards for radar equipment are

given in resolutions A. 222(VII), A. 278(VIII), A. 477(XII), A. 832(19), MSC.64(67) and

MSC.192(79).

A plotting table, plotting charts and instruments should be provided adjacent to each

station. A classroom equipped with a blackboard/whiteboard or flipchart and an

overhead projector, slide projector, or viewgraph, as appropriate, is also needed for

teaching the theoretical part of the course.



Teaching aids (A)

A1 Instructor manual (Part D of this course)

A2 Videomedia player

A3 Manufacturer's operational manual (Radar and ARPA)

A4 Video-cassettes or DVDs about the use of radar and ARPA. For example, target

tracking devices available from Videotel Productions, London.

IMO References (R)

R1 IMO Manila Amendments to the International Convention on Standards of

Training, Certification and Watchkeeping for Seafarers, 2010.

R2 IMO resolution MSC. 192(79): Revised Recommendation on Performance

Standards for Radar Equipment, 2004.

R3 IMO resolution MSC. 64(67) Annex 4: Recommendation on Performance

Standards for Radar Equipment, 1996.

R4 Assembly resolution A. 422(XI): Performance Standards for Automatic Radar

Plotting Aids, 1979.

R5 Assembly resolution A. 477(XII): Performance Standards for Radar Equipment,

1981.

R6 Assembly resolution A. 823(19): Performance Standards for Automatic Radar

Plotting Aids, 1995.

R7 IMO resolution MSC. 96(72): Recommendation on Performance Standards for

Devices to Measure and Indicate Speed and Distance, 2000.

R8 IMO SN.1/Circ.197: Operation of Marine Radar for SART Detection, 1997.

R9 IMO resolution MSC. 164(78): Revised Performance Standards for Radar

Reflectors, 2004.

R10 IMO resolution MSC. 74(69) Annex 3: Recommendation on Performance

Standards for a Universal Shipborne Automatic Identification System (AIS),

1998.

R11 IMO resolution MSC. 246(83): Performance Standards for Survival Craft AIS

Search and Rescue Transmitters (AIS-SART) for Use in Search and Rescue

Operations, 2007.

R12 IMO resolution MSC. 112(73): Revised Recommendation on Performance

Standards for Shipborne Global Positioning System (GPS), 2000.

R13 IMO resolution MSC. 116(73): Recommendation on Performance Standards for

Marine Transmitting Heading Devices (THDS), 2004.

R14 IMO The International Regulations for Preventing Collisions at Sea, 1972

(IMO-904).



Textbooks (T)

T1 Alan Bole, Alan Wall, Andy Norris, Radar and ARPA Manual, 3rd Edition, the

Boulevard, Langford Lane, Kidlington, Oxford, OX5 1 GB, UK, ISBN

978-0-08-097752-2, 2014.

T2 Liu Tong, Zhang Bin, Shipborne Navigational Radar, Dalian Maritime University

Press, 2016.

T3 W. Burger, Radar Observer's Handbook for Merchant Navy Officers, 9th Edition.

Glasgow, Brown, Son and Ferguson LTD., ISBN 0-85174-666-7, 1998,

Reprinted 2008.

T4 David F. Burch, Radar for Mariners, Library of Congress

Cataloging-in-Publication Data Burch, David, ISBN 0-07-139867-8, 2005.

T5 A.N. Cockcroft and J.N.F. Lameijer, A Guide to the Collision Avoidance Rules,

5th Edition. Oxford, Heinemann Professional Publishing, ISBN 0-434-90274-8,

1996.

T6 R. Lownsborough and D. Calcutt, Electronic Aids to Navigation: Radar and

ARPA, London, Edward Arnold, ISBN 0-340-59258-3, 1993.

T7 I. Smith and R. A. Mulroney, Parallel Indexing Techniques, Warsash Publishing,

ISBN 0 948646 55 1, 1979.

T8 Andy Norris, "Civil marine radar," Chapter 22 of The Radar Handbook, 3rd Ed.,

Merrill Skolnik. (ed.), New York: McGraw-Hill Companies, 2008, ISBN

978-0-07-148547-0.

T9 J. N. Briggs, Target Detection by Marine Radar, Institution of Electrical

Engineers, London, 2004, ISBN 0-86341-359-5.

T10 Samuel Decota, Radar observer manual, edition 6, ISBN 193318616X

Bibliography (B)

B1 IEC 62388: Maritime Navigation and Radio Communication Equipment and

Systems - Shipborne Radar - Performance Requirements, Methods of Testing

and Required Test Results, Edition 1, 2007.

B2 ITU-R M.1371-5: Technical Characteristics for an Automatic Identification

System Using Time Division Multiple Access in the VHF Maritime Mobile Band,

2014.

B3 IEC 61097-14: Global Maritime Distress and Safety System (GMDSS) - Part 14:

AIS Search and Rescue Transmitter (AIS-SART) - Operational and

Performance Requirements, Methods of Testing and Required Test Results,

Edition 1, 2010.

B4 ITU-R M.628-4 Recommendation: Technical Characteristics for Search and

Rescue Radar Transponders, 2006.

B5 IALA Recommendation R-101: On Marine Radar Beacons (RACONS) Edition 2,

2004.

B6 IEEE Std 686™: IEEE Standard Radar Definitions, 2008.



Video (V)

V1 Target Tracking Devices (Code 948)

V2 Collision Avoidance CD-ROM Version 1.7 (Code 819)

Available from: Videotel Marine International Ltd

84 Newman Street

London, W1P 3LD, UK

Tel: +44 (0)20 7299 1800, Fax: +44 (0)20 7299 1818

E-mail: mail~videotelmail.com

URL: www.videotel.co.uk

V3 Radar Observation and Plotting (CBT# 0049)

V4 ARPA Theory (CBT# 0050)

Available from: Seagull Maritime AS

Gamleveien 36

P.O. Box 1062

N-3194 Horten, Norway

Phone: +47 33 03 09 10

Fax: +47 33 04 62 79

Email: [email protected]

http://www.videotel.co.uk/

mailto:[email protected]



STCW 2010 A-II/1

Mapping of IMO Model

course 1.07 topics



STCW 2010 Table A-II/1 mapping of IMO model course 1.07 topics

STCW 2010 Table A-II/1 IMO Model course 1.07

Competence Knowledge, Understanding and Proficiency Topic Sub-topic Knowledge, Understanding and Proficiency

Use of radar and

ARPA to maintain

safety of navigation

Note: Training and

assessment in the

use of ARPA is not

required for those

who serve

exclusively on ships

not fitted with

ARPA. This

limitation shall be

reflected in the

endorsement

issued to the

seafarer concerned

Radar navigation

Knowledge of the fundamentals of radar and

automatic radar plotting aids (ARPA)

1 1.1

1.2

1.3

1.1 The fundamental principles of radar

1.2 Magnetic safe distances

1.3 Radiation hazards and precautions

Ability to operate and to interpret and analyse

information obtained from radar, including the following:

3 3.4

3.5

3.4 Maps, navigation lines and routes for radar navigation

3.5 Electronic chart overlay on radar picture

Performance, including:

.1 factors affecting performance and accuracy 1 1.4

1.7

1.4 Factors of radar equipment affecting radar detection

1.7 Performance standards for radar equipment in resolutions MSC. 192(79), annex 4 of

MSC. 64(67) and A. 477(XII)

.2 setting up and maintaining displays 2 2.1 2.1 Setting up and maintaining optimum radar display

.3 detection of misrepresentation of information,

false echoes, sea return, etc. Racons and SARTs

1

3

1.5

1.6

3.2

1.5 Factors external to radar equipment affecting radar detection

1.6 Factors affecting normal radar observation

3.2 Radar navigation aids



Use, including:

.1 range and bearing; course and speed of other

ships; time and distance of closest approach of

crossing, meeting overtaking ships

2

4

2.2

4.2

4.3

2.2 Accurate measurement of ranges and bearings

4.2 Course, speed and aspect of a target ship

4.3 Determination of closest point of approach (CPA) and time to closest approach (TCPA)

.2 identification of critical echoes; detecting course

and speed changes of other ships; effect of

changes in own ship's course or speed or both

3

4

3.1

4.4

3.1 Radar position-fixing

4.4 Effects of course alteration and speed change

.3 application of the International Regulations for

Preventing Collisions at Sea, 1972, as amended

7 7 Application of COLREGs when using radar

.4 plotting techniques and relative- and true-motion

concepts

4 4.1

4.5

4.1 Relative motion triangle

4.5 Report of radar plotting data

.5 parallel indexing 3 3.3 3.3 Parallel index line techniques in radar navigation

Principal types of ARPA, their display

characteristics, performance standards and the

dangers of over-reliance on ARPA

5

6

5.4

6.7

5.4 IMO performance standards for ARPA or target tracking (TT) and AIS reporting

functions

6.7 Risks of over-reliance on ARPA or TT and AIS reported information

Ability to operate and to interpret and analyse

information obtained from ARPA, including:

.1 system performance and accuracy, tracking

capabilities and limitations, and processing delays

5

6

5.6

5.7

6.5

5.6 Tracking capabilities and limitations

5.7 Processing delays of target tracking and information delays of AIS reporting

6.5 Correctly identify and interpret Causes of errors in displayed data



.2 use of operational alarms and system tests 6 6.6 6.6 System operational tests to determine data accuracy

.3 methods of target acquisition and their limitation 5 5.5 5.5 Criteria for acquisition of radar targets and activation of AIS targets

.4 true and relative vectors, graphic representation of

target information and danger areas

5 5.1

5.2

5.3

5.1 Display characteristics of tracked targets

5.2 Display characteristics of AIS reported targets

5.3 Association of radar tracked targets with AIS reported targets

.5 deriving and analyzing information, critical

echoes, exclusion areas and trial manoeuvres

6 6.1

6.2

6.3

6.4

6.5

6.1 Setting up and maintaining ARPA or TT display

6.2 Setting up and maintaining AIS display

6.3 Operation of ARPA or TT and AIS reporting functions to obtain target information

6.4 Possible errors of interpretation of target data

6.5 Causes of errors in displayed data



Part B: Course Outline and Timetable

Introduction

Part B is a general description of what materials should be presented and its

sequences of presentation. In the following table, this course outline is divided into

7 topics and further subdivided into 38 sub-topics corresponding to the competencies

and KUPs required by table A-II/1 of the STCW.

The training is delivered through lectures, demonstrations and/or practical training.

The contents of each topic and sub-topic and their allocated hours are duly specified.

However, the course materials have to be adjusted according to the target group as

well as the time needed for individual topics. The course timetables are intended for

general guidance only and may be adjusted for the varying needs for the different

target groups. However, it may be possible for experienced instructors, by amending

the timetables and presentations, to accommodate different target groups on the

same course.

Lecture

The lecture should be presented in general teaching scenarios. The presentation of

theoretical knowledge may be achieved in various ways combining with diagrams,

pictures, sketches and radar application practices.

Effective teaching methodology involves delivering the relevant knowledge to the

trainees by certain techniques, and enhancing the knowledge by further explanation.

For example, firstly, instructors should introduce the general contents to the trainees,

then illustrate each objective in detail and finally provide a summary and conclusion.

Utilization of a projector and distribution of handouts to the trainees is an efficient way

to supplement lectures and is highly advisable.



Demonstration

It is essential for the officer in charge of a navigational watch to ensure the safety of

navigation by understanding the fundamental principles of the radar system and its

composition and efficient and proper use of radar and ARPA.

Demonstration provides an effective link between lectures and practical training, and it

is a helpful approach for the trainee to thoroughly understand the theoretical

knowledge and enhance their operational skills efficiently. During the demonstration

and practical training, the instructor should assist the trainees to attain the training

objectives by demonstrating the operational key points and skills.

Practical training

Experience shows that well-designed practical training will substantially improve the

training outcome. If the practical training is performed on a simulator, the instructor

should expend efforts to ensure that the training exercises are presenting real ship

and practical situations.



Course outline

Knowledge, understanding and proficiency Lecture (h) Demonstration (h) Practical training (h)

1 Basic theory and operation principles of marine radar system

1.1 Fundamental principles of radar

Demonstration and practical training 1-1 Demonstration of radar system configuration and installation

location on board






1.7 Performance standards for radar equipment in Resolutions MSC. 192(79), Annex 4 of MSC. 64(67) and

A. 477(XII)

2.0

0.05

0.05

3.0

3.8

1.6

1.0

11.5

0.5

0.5


2.1 Setting up and maintaining optimum radar display

Demonstration and practical training 2-1 Radar setting up and adjustment


4.5

1.5

6.0

1.0

1.0

3.0

3.0




3 Using radar to ensure safe navigation


Demonstration and practical training 3-1 Radar position-fixing


3.3 Parallel index line techniques

Demonstration and practical training 3-2 PI line navigation

3.4 Maps, Navigation Lines and routes for radar navigation

Demonstration and practical training 3-3 Radar maps, navigation lines and routes navigation

3.5 Electronic chart overlay on radar picture

0.9

0.5

0.8

0.4

0.4

3.0

0.2

0.4

0.4

1.0

0.8

1.6

1.6

4.0

4 Manual radar plotting


4.2 Course, speed and aspect of target ship

4.3 Determination of CPA and TCPA

Demonstration and practical training 4-1 Acquiring motion elements of target ships


Demonstration and practical training 4-2 Effects of course alterations on RML

Demonstration and practical training 4-3 Effects of speed changes on RML


0.5

2.0

0.5

2.5

0.5

0.2

0.2

0.2

0.8

0.8

0.8




Demonstration and practical training 4-4 Manual radar plotting report

6

0.2

0.8

0.8

3.2

5 ARPA system or radar target tracking (TT) and AIS reporting functions




5.4 IMO performance standards for ARPA or TT and AIS reporting functions

5.5 Criteria for acquisition of radar targets and activation of AIS targets


5.7 Delay of target tracking processing and AIS reported information

0.7

0.2

0.3

0.5

0.5

0.5

0.3

3.0

6 Operation of ARPA or radar target tracking (TT) and AIS reporting functions



6.3 Operation of ARPA or TT and AIS functions to obtain target information

6.4 Errors of interpretation of target data


6.6 System operational tests to determine data accuracy

0.7

0.5

2.0

0.8

1.0

0.5





Demonstration and practical training 5 & 6 -1 Operation of ARPA or TT and AIS reporting functions

0.5

6.0

3.0

3.0

12.0

12.0

7 Application of the COLREGs when using radar

7.1 Proper use of radar and full and complete interpretation of radar information

7.2 Radar related factors affecting safe speed

7.3 Methods and characteristics of acquiring sufficient radar information

7.4 Actions to avoid collision based on sufficient radar information and in accordance with COLREG rules

7.5 Timing to use radar

Demonstration and practical training 7-1 Ship handling for integrated collision avoidance

0.5

0.3

0.5

0.5

0.2

2.0

2.0

2.0

10.0

10.0

Total 78.0 37.5 8.3 32.2

Because the required performances in Topics 5 and 6 involve comprehensive and systematic practical training, it is impractical to recommend

time for each performance element in demonstration and practical training.

The lecture hours, demonstration hours and practical training hours are for guidance only. Instructors may adapt the time allocated to the

lectures, demonstration and practical training depending on the needs of the trainees.



Course timetable

Period

Day Morning Afternoon

Day 1 1.1 Fundamental principles of radar

Demonstration and practical training 1-1

Demonstration of radar system configuration

and installation location on board



1.4 Factors of radar equipment affecting radar

detection

1.4 Factors of radar equipment affecting

radar detection (continued)

1.5 Factors external to radar equipment

affecting radar detection

Day 2 1.5 Factors external to radar equipment

affecting radar detection (continued)

1.5 Factors external to radar equipment

affecting radar detection (continued)

1.6 Factors affecting normal radar

observation

1.7 Performance standards for radar

equipment in Resolutions MSC. 192(79),

Annex 4 of MSC. 64(67) and A. 477(XII)

Day 3 2.1 Setting up and maintaining an optimum

radar display

2.1 Setting up and maintaining an optimum

radar display (continued)

2.2 Accurate measurement of ranges and

bearings

Day 4 Demonstration and practical training 2-1

Radar setting up and adjustment




3.4 Maps, Navigation Lines and routes for

radar navigation

3.5 Electronic chart and radar picture overlay

for radar navigation

Day 5 Demonstration and practical Training 3-1

Radar position-fixing

Demonstration and practical training 3-2 PI

line navigation


Radar maps, navigation lines and routes

navigation

Day 6 4.1 Relative motion triangle



4.4 Effects of course alteration and speed

change





Acquiring motion elements of target ships


Effects of course alterations on RML


Effects of speed changes on RML


Manual radar plotting report


5.2 Display characteristics of AIS reported

targets

5.3 Association of radar tracked targets with

AIS reported targets

5.4 IMO performance standards for ARPA or

TT and AIS reporting functions

5.5 Criteria for acquisition of radar targets

and activation of AIS targets


5.7 Delay of target tracking processing and

AIS reported information

Day 8 6.1 Setting up and maintaining ARPA or TT

display


6.3 Operation of ARPA or TT and AIS functions

to obtain target information

6.3 Operation of ARPA or TT and AIS

functions to obtain target information

(continued)



6.6 System operational tests to determine

data accuracy

6.7 Risks of over-reliance on ARPA or TT and

AIS reported information

Day 9 Demonstration and practical training 5 & 6 -1

Operation of ARPA or TT and AIS reporting

functions

Demonstration and practical training 5 & 6-1

(continued)

Day 10 Demonstration and practical training 5 & 6-1

(continued)

Demonstration and practical training 5 & 6-1

(continued)

Day 11 Demonstration and practical training 5 & 6-1

(continued)

7.1 Proper use of radar and full and complete

interpretation of radar information


7.3 Methods and characteristics of acquiring

sufficient radar information

7.4 Actions to avoid collision based on

sufficient radar information and in accordance

with COLREG rules

7.5 Timing to use radar



Note

Teaching staff should note that the timetables are suggestions only as regards

sequence and length of time allocated to each objective. These factors may be

adapted by lecturers to suit individual groups of trainees depending on their

experience, ability, equipment and staff available for training. Particular attention is

drawn to the fact that the length of time for the presentation, demonstration and

practical training may be adjusted to suit the needs of different target groups.

Needless to say, practical training assessment is indispensable.

Day 12 Demonstration and practical training 7-1 Ship

handling for integrated collision avoidance


(continued)


(continued)


(continued)



Part C: Detailed Teaching Syllabus

Introduction

The detailed teaching syllabus is presented as a series of learning objectives. The

objective, therefore, describes what the trainee must do to demonstrate that the

specified knowledge or skill has been transferred.

Thus each training outcome is supported by a number of related performance

elements in which the trainee is required to be proficient. The teaching syllabus shows

the required performance expected of the trainee in the tables that follow.

The topics and sub-topics of the course have been given in Part B. In Part C, the

detailed teaching syllabus breaks down each topic/sub-topic into Learning Objectives

under the column of "Knowledge, understanding and proficiency". A table is

established which lists each topic or sub-topic and the corresponding guidance in

Part B of the STCW Code. Simultaneously, the table provides the teaching aids and

references as well. Thus the user of the model course can clearly understand the

fundamental condition of each Learning Objective.

In order to assist the instructor, references are shown to indicate IMO references and

publications as wells as textbooks and teaching aids that instructors may wish to use

in preparing and presenting their lessons.

The material listed in the course framework has been used to structure the detailed

teaching syllabus, in particular:

Teaching aids (indicated by A) which includes:

IMO references (indicated by R)

Textbooks (indicated by T) and

Bibliography (indicated by B)

which will provide valuable information to instructors.

Note

In designing lesson plans from the Detailed Teaching Syllabus, instructors should aim

to produce exercises which enable trainees to demonstrate the ability of

understanding and practical application of the course theory and knowledge. In

particular trainees must develop an understanding of the implications of possible

errors and other factors affecting radar performance, accuracy and its limitations. The

practical significance of these factors to the proper use of radar as an aid to

navigation is as important as the knowledge itself.



Detailed teaching syllabus

Knowledge, understanding and proficiency

References

Textbooks Teachin

g aids STCW Code

B-I/12

Other

References

1 The basic theory and operation principles of a marine radar system (12.0 h) R1;R2;B1;R3;

R4;R5;R6;R7

T1;T2;T3;T4 A1;A2;A3;A4

1.1 The fundamental principles of radar (2.5 h) T1;T2;T3;T4 A1;A2

.1 explains the principles of range and bearing measurement pa4.1

.2 states the configuration of a marine radar system pa4.1

.3 states the composition and the principles of basic radar pa4.1 A1

practical training: demonstrates radar system configuration and installation location (0.5 h)

1.2 Magnetic safe distance (0.05 h) pa4.3 T1;T3

1.3 Radiation hazards and precautions (0.05 h) pa4.4 T1;T2;T3

1.4 Factors of radar equipment affecting radar detection (3.0 h) R1;R2;B1;R3 T1;T2;T3 A1;A2

.1 states the relationship between the maximum detection range and power, pulse length, pulse recurrence

frequency, and receiver sensitivity

pa4.1

.2 states the relationship between the minimum detecting range and pulse length, vertical beam width,

change-over time of antenna transmitting/receiving

pa4.1;4.3



.3 explains effects on range and bearing accuracy of synchronization error, CCRP error, pixel/spot size, and

pulse length, variable range marker error, HBW, heading marker error, centring error, and THD error

pa4.1

.4 explains effects on range and bearing discrimination of HBW, pixel/spot size, range scale, pulse length, gain,

and information processing

pa4.1

1.5 Factors external to radar equipment affecting radar detection (3.8 h) R1;R2;B1;R3 T1;T2;T3 A1;A2

.1 explains effects of antenna height on detection ranges pa4.3;5.3

.2 explains effects of atmospheric conditions on detection ranges (super-refraction, sub-refraction, surface duct,

elevated duct)

pa5.6

.3 states effects of precipitations on detection ranges (rain, hail, snow, fog) pa5.7

.4 identifies blind and shadow areas, permanent blind and shadow sectors and their relationships with antenna

location

pa4.3;5.9

.5 states influences of target characteristics on detection ranges (aspect, shape, composition, size) pa5.4

.6 explains influences of clutter and interference on radar detection (sea clutter, rain clutter, radar interference) pa5.7;5.8;5.10

1.6 Factors affecting normal radar observation (1.6 h) R1;R2;R3;B1 T1;T2;T3 A1;A2

.1 explains causes and effects of indirect echoes pa4.3;5.9;6

.2 explains causes and effects of multiple echoes pa4.3;6

.3 explains causes and effects of side lobe echoes pa4.1;4.3;6

.4 explains causes and effects of second trace echoes pa4.3;6

.5 states effects on radar picture of power lines, bridges crossing rivers and estuaries, low altitude aircrafts pa6



.6 explains effects of the ship in seaway pa5.5

1.7 Performance standards for radar equipment in Resolutions MSC. 192(79), Annex 4 of MSC. 64(67) and

A. 477(XII)

R1;R2;R3;R4;

R5;R6;R7

T1;T2

.1 states requirements for detection ranges (long and short ranges) pa4.2

.2 states requirements for accuracies (range and bearing) pa4.2

.3 states requirements for discriminations (range and bearing) pa4.2

2 Radar setting and operation in accordance with manufacturer's instructions (10.0 h)

2.1 Setting up and maintaining optimum radar display (8.5 h) T1;T2;T3,V3 A1;A2;A3

.1 operates main controls (power, antenna)

.2 operates transmitter controls (transmission, pulse length, pulse repetition frequency) pa8.3

.3 adjusts receiver controls (tuning, gain, anti-clutter sea) to achieve an optimum picture pa5.2;5.8;8.3;8.4

.4 adjusts display controls/menus (display menus and controls, range selector, heading line control, off-centring

display, fixed range rings, VRMs, EBLs, cursor, ant-clutter rain, automatic anti-clutter, interference rejection,

echo stretch, echo average, target trails)

pa5.2;5.8;5.10;

8.4

.5 demonstrates correct orders of making adjustments to radar and states criteria for optimum setting of the

controls

pa5.2;5.8;8.3

.6 states skills to detect small or poor echoes pa5.2;5.8;8.3

.7 describes effects of saturation of receiver noise and/or clutter pa8.3

.8 states the importance of frequent changes in range scale pa8.5



.9 identifies different types of presentation modes (relative-motion mode, true-motion mode, head-up orientation

mode, north-up orientation mode, course-up orientation mode)

pa8.1

.10 explains advantages and limitations of different types of presentation modes pa8.1;15

.11 explains the need of heading information for relative stabilized presentation modes, and the need of heading

and speed input for true motion presentation modes

pa8.2;8.3

.12 identifies effects of transmitting heading error on stabilized and true motion presentation modes pa8.2

.13 identifies effects of SDME error on true motion presentation modes pa8.2;8.3

.14 operates specific controls/menu (presentation mode, speed controls, reset controls, heading information) pa8.3;8.4

.15 identifies maladjusted controls and explains their effects and dangers pa8.3;8.4

.16 detects and corrects the maladjustments pa8.3

.17 states effects of incorrect speed setting and CMG correction on true motion presentation modes pa8.3

.18 describes the purpose and use of the performance monitor pa8.3;8.5

.19 records radar data (radar logs, radar maintenance records, radar shift records) pa8.5

.20 explains how propagation conditions can affect target detection pa5.6

.21 states effects of incorrect CCRP setting

practical training: Demonstrates operational skills to set up and adjust radar system (4.0 h)

2.2 Accurate measurement of ranges and bearings (1.5 h) T1;T2;T3,V3

.1 states methods and accuracies of measuring ranges (fixed range rings, VRMs, cursor) pa9.1;9.2;9.3

.2 emphasizes the importance of accuracy when measuring ranges pa9.2;9.7



.3 states methods and accuracies of measuring bearings (EBLs, cursor) pa9.4;9.5;9.6

.4 emphasizes the importance of accuracy when measuring bearings pa9.5;9.7 R2;R4

.5 checks and corrects the errors in range and bearing pa9.7

.6 states measuring ranges and bearings with offset EBLs and VRMs pa9.1;9.4

3 Using radar to ensure safe navigation (8 h) T1;T2;T3,V3

3.1 Radar position-fixing (1.9 h)

.1 describes characteristics of good, conspicuous radar targets pa7

.2 describes characteristics of poor radar target echoes pa7

.3 states position-fixing methods based on radar bearings and ranges pa11.1

.4 explains position-fixing errors and methods to improve fixing accuracy pa11.2

.5 checks the reliability of radar position-fixing repeatedly by using other navigational aids pa11.3

.6 compares coast features on chart with that on radar picture pa17.7;17.8

practical training: Demonstrates operational skills to fix ship's position by radar (1.0 h)

3.2 Radar navigation aids (0.5 h)

.1 describes passive aids (corner reflector and Luneburg lens reflector) pa7

.2 describes active aids (racon, echo enhancer and AIS AtoN) pa7

.3 describes radar SART and AIS SART pa7

.4 identifies data information of passive and active aids pa7



3.3 Parallel index line techniques in radar navigation (2.8 h)

.1 establishes and uses parallel index lines

.2 states the correct actions taken when the echo deviates from the Pl line

.3 uses multiple PI lines

.4 establishes and uses PI lines for two range scales

.5 states the importance of "wheel over" position

.6 demonstrates use of "wheel over" position

.7 states the importance of a safety margin

.8 demonstrates the use of safety margins

.9 interprets real motion of ship from a tracked echo

.10 takes appropriate actions to counteract influence of currents

.11 demonstrates use of a line of turn

.12 establishes and uses PI lines for radial turns

practical training: Demonstrates operational skills to use parallel index lines for safe navigation (2.0 h)

3.4 Maps, navigation lines and routes for radar navigation (2.4 h) R1;R2 A1;A3

.1 demonstrates use of maps, navigation lines, routes in reference to own ship or a certain geographical position

.2 removes maps, navigation lines and routes

practical training: Demonstrates operational skills to use maps, navigation lines, routes for safe navigation (2.0 h)



3.5 Use of Electronic chart overlay on the radar picture (0.4 h) R1;R2 A1;A3

.1 displays ENC and other vector chart information

.2 switches off electronic chart display on radar screen

.3 explains "picture frozen" alarm and signal source or sensor failure alarms

4 Manual radar plotting (10.0 h) T1;T3;T5,V3 A1;A2;A4

4.1 Relative motion triangle (0.5 h)

.1 explains the meanings of the relative motion triangle, various vectors and angles pa10

.2 constructs a relative motion triangle on a plotting chart pa10

4.2 Course, speed and aspect of a target ship (2.0 h)

.1 measures range and bearing of a target ship at an appropriate interval and frequency pa11.4

.2 determines course, speed and aspect of a target ship in relative presentation modes (stabilized or

unstabilized)

pa10;12.1

.3 determines course, speed and aspect of a target ship in true presentation modes pa10;12.1

.4 states factors affecting the accuracy of derived course, speed and aspect pa15;16

.5 determines set and drift of current by observing a fixed target

4.3 Determination of closest point of approach (CPA) and time to closest approach (TCPA) (1.5 h)

.1 determines CPA and TCPA in relative presentation modes (stabilized and unstabilized) pa13

.2 determines CPA and TCPA in true presentation modes pa13

.3 states factors affecting the accuracy of CPA and TCPA pa13



Practical training: acquires motion elements of target ships (1.0 h)

4.4 Effects of course alteration and speed change (4.5 h)

.1 identifies effects of course alteration and/or speed change of a target ship pa14.1

.2 compares advantages and disadvantages of radar observation with that of visual look-out pa12.2

.3 explains the time delay between change of course or speed and detection of that change pa14.2

.4 states advantages of bearing stabilization in relative motion presentation modes pa15

.5 explains effects of changes in own ship's course or speed on the observed movement of target pa15;16

.6 states effects of small changes of course and/or speed on detecting change and change accuracy of true

vector

pa14.3

practical training: achieves effects on RML due to course alteration of own ship (1.0 h)

practical training: achieves effects on RML due to speed change of own ship (1.0 h)

4.5 Report of radar plotting data (1.5 h) pa17.4

practical training: Demonstrates operational skills to make a report of manual radar plotting (1.0 h)

5 ARPA system or TT and AIS reporting functions (3.0 h) R2;B1;R4

R5;R6;R10

T1;T2;T3,V1,

V4

A1;A2;A3;A4

5.1 Display characteristics of tracked targets (0.7 h) R2;B1;R4;R5;R6

.1 describes characteristics of vectors pa21 R2;B1;R4;R6

.2 describes characteristics of graphics pa21 R2; B1;R4;R5;R6



.3 describes characteristics of alphanumeric data output pa21 R2;B1;R4;R6

.4 describes characteristics of PADs pa21 R2;B1;R4;R6

5.2 Display characteristics of AIS reported targets (0.2 h) R2;B1;R10 A1, A2,V1,V4

.1 describes characteristics of vectors

.2 describes characteristics of graphics

.3 describes characteristics of alphanumeric data output

5.3 Association of radar tracked targets with AIS reported targets (0.3 h) R2;B1;R10

.1 states the concept of the association of radar tracked targets with AIS reported targets

.2 demonstrates association of radar tracked and AIS reported targets

.3 states principles of association and factors affecting association

5.4 IMO performance standards for ARPA or TT and AIS reporting functions (0.5 h)

.1 states the accuracy requirements for ARPA or TT pa22 R2;R3;R5;R6;

R7;R11

.2 states the requirements for target acquisition and tracking pa22 see above

.3 lists the requirements for operational alarms of ARPA or TT and AIS reporting functions pa22 see above

.4 states the alphanumeric data available from ARPA or TT and AIS reporting functions pa22 see above

.5 explains the effects of sensor errors on ARPA or TT functions pa22;23 R2;R3;R5 R6;R7

.6 states the requirements for inputs from THD, SDME, EPFS and AIS sensors pa23;24.1 R2;R3;R5;R7;R11



.7 states the requirements for association of radar tracked and AIS reported target R2;B1;R10

5.5 Criteria for acquisition of radar targets and activation of AIS targets (0.5 h) R2;B1;R4;R6;R10

.1 states the criteria for radar target acquisition and AIS target activation pa25.1; 25.2;29 R2;B1;R4;R6

.2 states various ways for radar target acquisition pa25.1; 25.2;29 R2;B1;R4;R6

.3 states the criteria for automatic acquisition specified in radar operation manual pa25.1;29 R2;B1;R4;R6

.4 states the criteria for manual acquisition pa25.2;29 R2;B1;R4;R6

.5 states the requirements for target number acquired by ARPA or TT and reported by AIS pa22 R2;B1;R4;R6;R10

.6 states that tracked targets may be cancelled if not posing a potential threat (when tracking range limit has

been reached)

pa25.3;29 R2;B1;R4;R6

.7 describes the tracking results of targets in acquisition, guard and exclusion zones pa32.7 R2;B1;R4;R6

5.6 Tracking capabilities and limitations (0.5 h) R2;B1, R4;R6

.1 outlines the principles of target tracking pa25.3;25.4;26;2

9

R2;B1,R4;R6

.2 describes lost target and its alarm pa25.3;29 R2;B1;R4,;R6

.3 states common circumstances leading to "target swap" pa25.4;29 R2;B1;R4;R6

.4 describes effects of "target swop" on displayed data pa25.4;29 R2;B1;R4,;R6

5.7 Processing delays of target tracking and information delays of AIS reporting (0.3 h) R2;B1, R4;

R6;R10

.1 explains delay in data display of tracked target pa26 R2;B1;R4;R6



.2 explains delay in data display when the target ship manoeuvres pa26 R2;B1;R4;R6

.3 states that there may be a delay of up to three minutes before full accuracy of derived information may be

attained after acquisition or a manoeuvre of a target

pa26 R2;B1;R4;R6

.4 states delay in data display of AIS dynamic information R2;R10

6 Operation of ARPA or radar target tracking (TT) and AIS reporting functions (6 h) R2;B1;R3;R4

R5;R6;R10

T1;T2;T3,V1,

V3

A1;A2;A3;A4

6.1 Setting up and maintaining ARPA or TT display (0.7 h) R2;B1;R3;R4;R5,

R6

.1 adjusts radar sensors for optimum presentations pa32.3;32.8 R2;B1;R3;R4;R5

;R6

.2 sets up and confirms THD and SDME sensors pa32.3;32.4;32.8 R2;B1, R3;R4;R5;

R6

.3 sets up an appropriate presentation modes (motion modes, orientation modes, range scales, past positions,

vector modes, PADs)

pa21;30;32.2 R2;B1;R4, R6

.4 sets up CPA limit/TCPA limit pa27 R2;R3;R5;R7

.5 acquires targets manually pa25.2;29;32.5 R2;R3;R5;R7

.6 sets up automatic guard/acquisition and exclusion zones pa25.1;32.7 R2;R3;R5;R7

6.2 Setting up and maintaining AIS display (0.5 h) R2;R3;R11

.1 sets and verifies EPFS sensor R2;R3;R11;R17

.2 sets up and verifies THD sensor R2;R3;R11;R19



.3 sets up and verifies SDME sensor R2;B1;R7;R10

.4 verifies AIS information of own ship R2;B1,R10

.5 verifies AIS reported targets R2;B1;R10

.6 sets up appropriate presentation modes for AIS targets (sleeping targets, activated targets, selected targets,

vectors, heading line, past positions, sea-stabilized and ground-stabilized)

R2;B1;R11

6.3 Operation of ARPA or TT and AIS reporting functions to obtain target information (2.0 h) R2;B1;R4;R6;R10 V1,V3

.1 obtains information from relative and true vectors in both relative and true motion presentation modes pa30;34 R2;B1;R4;R6

.2 states the importance of switching between true and relative vectors pa30 R2;B1;R4;R6

.3 obtains information from past positions pa31 R2;B1;R4;R6

.4 uses predicted areas of danger (PADs), where fitted pa30.1;30.2;30.3 R2;B1;R4;R6

.5 obtains information from AIS reported targets R2;B1;R10

.6 associates radar tracked targets with AIS reported targets R2;B1;R10

.7 assesses the encounter situations and collision risks by associated information R2; B1,;R10

.8 performs trial manoeuvre pa30.2;34.6;34.7 R2;R1;R10

.9 sets up and acknowledge target tracking operational alarms (target capacity overflow, dangerous target, new

target entry, lost target)

pa27 R2;B1

.10 sets up and acknowledge AIS operational alarms (target capacity overflow, dangerous target, lost target) R2;B1;R10

6.4 Possible errors of interpretation of target data (0.8 h) R2;B1;R3;R4;

R5;R6;R10



.1 interprets possible errors due to improper sensors' setting and/or adjustment pa23 R2;B1,R3;R4;

R5;R6;R10

.2 explains misunderstandings of information deriving from alphanumeric data and information from vectors pa30;34.2;

34.3;34.4

R2;B1;R4;R6

.3 explains possible errors due to incorrect interpretations of radar presentation and vector modes pa30.1;30.2;30.3 R2;B1;R4;R6;R10

.4 explains possible errors due to incorrect interpretations of own ship's speed pa34.2;34.3;

34.4;34.6

R2;B1,R4;R7

.5 explains possible errors resulting from incorrect interpretations of a trial manoeuvre pa30.2;34.6;34.7 R2;B1;R4;R6

.6 explains that reacquired "the lost target" may present false course alteration and speed change pa26 R2;R3;R5;R7;R11

.7 states that PADs do not indicate mutual threats between targets pa30.1;30.2;30.3 R2;R3;R5;R7

.8 states that the length of line from target to PAD is not an indicator of target speed pa30.1 R2;R3;R5;R7

.9 states that past position presentation may not necessarily be in the same mode as vector pa30.3;31 R2;R3;R5;R7

.10 states that a change of direction in the relative past positions does not necessarily indicate a target

manoeuvre

pa31 R2;R3;R5;R7

.11 explains that misinterpretations of ARPA or TT and AIS information may lead to false assessment of

situations

pa30.1;30.2;30.3 R2;R3;R5;R7;R11

6.5 Causes of errors in displayed data (1.0 h) R2;R3;R5;R7

.1 explains effects of errors caused by the radar sensor on data display pa23;24.1 R2;R3;R5;R7

.2 explains effects of heading errors on data display pa23;24.1 R2;R3;R5;R7



.3 explains effects of speed errors on data display pa23;24.1 R2;B1;R4;R6

.4 explains that tracking data is unreliable when own ship or target ship is manoeuvring pa26 R2;B1;R4;R6

.5 states that satisfactory target tracking performance is indicated by smoothness of past positions pa31 R2B1;R5;R7

.6 explains causes of data errors of AIS reported target R2;B1;R4;R6;R10

6.6 System operational tests to determine data accuracy (0.5 h) R2;B1,;R5;R7;R11

.1 uses system diagnosis to test system status (including errors, troubles) pa28.1 R2;B1;R4;R6

.2 operates test programmes to check system performances against known solutions pa28.1 R2;B1;R4;R6

.3 demonstrates performance check by manual plotting, including a trial manoeuvre pa33 R2;B1,;R4;R6

.4 takes correct actions after anomaly of ARPA or TT and AIS reported information pa28.2 R2;B1;R4;R6;R10

6.7 Risks of over-reliance on ARPA or TT and AIS reported information (0.5 h) R2;B1;R4;R6;R10

.1 states limitations of ARPA or TT and AIS reported information pa20.2

.2 reacts correctly to operational alarms pa27

.3 states hazards of small predicted passing distances (CPA and BCR) pa20.1

.4 explains that sensor input alarms only occur on failure of input and do not respond to inaccurate inputs pa23;28.2

practical training: Demonstrates operational skills to operate ARPA or TT and AIS reporting functions

proficiently (15.0 h)

7 Application of COLREGs when using radar (14.0 h) R1;R2 T1;T2;T4;T5,

V2

A1;A2;A3;A4

7.1 states that radar is used as a means of proper look-out, and states the importance of the radar systematic pa17.4;17.8



observations, full and complete interpretation of radar information (0.5 h)

7.2 emphasizes on radar related factors which can affect safe speed (0.3 h) pa17.2

7.3 lists the methods and characteristics that can acquire sufficient radar information to avoid collision or

close-quarters situations (0.5 h)

pa17.1;17.3;17.4

7.4 makes substantial alteration of course or/and change of speed to avoid collision or close-quarters situations

based on sufficient radar information and in accordance with COLREG rules (0.5 h)

pa17.1;35

7.5 states the timing to use radar by day in clear weather, at clear night when there are indications that visibility

may deteriorate, and at all times in or near the area of restricted visibility and in congested waters (0.2 h)

pa17.5;17.6

Practical training: Demonstrates operational skills to use radar for integrated collision avoidance in complex

situations (12.0 h)



Part D: Instructor Manual

Introduction

This manual reflects the views of the course designer on methodology and

organization considered relevant and important in the light of his/her experience as an

instructor. The following guidance given here may be of value initially, the course

instructors are advised to work out their own methods and ideas, refining course

material and developing it further, and discarding ideas and methods which are not

found effective.

The course developer and instructors should also bear in mind that preparation and

planning constitute a major contribution to effective presentation of the course.

The instructor's manual provides guidance on the material that is to be presented

during the course. Based on Knowledge, Understanding and Proficiency in Part C,

the instructor manual (Part D) is intended to provide the most detailed communication

to the model course instructors in terms of teaching organization and structure,

sequence of lectures, possible problems and solutions in the course, etc. The

instructors are recommended to study carefully this part and work out lesson plans in

consideration of the quality and demand of trainees, the local conditions of each

country (region), and the status of radar technology.

Structure

This course is comprised of 7 topics, each topic includes 3 sections, namely detailed

teaching packages, assessment techniques and teaching guidance.

Guidelines for use

The following detailed teaching package is for informational guidance only to course

developers and instructors. It is not meant to present instructors with a rigid teaching

package which they are expected to follow but rather, due to nature of the subject, to

assist in formulating presentations and assessments in support of the Detailed

Teaching Syllabus.

The detailed teaching packages are the core section for each topic.

Detailed teaching packages: The detailed teaching packages are the core section

for each topic. By reading the summary, it will help instructors to have a quick and

clear overall understanding of the primary content of the topic. It not only increases



lesson preparation efficiency, but also facilitates the organization and cohesion in the

course of lesson preparation and delivery. In the detailed teaching packages, the main

learning objectives are specified, many of which provide the resources that may be

used in the teaching process for the convenience of instructors, such as principlal

block diagrams of radar, schematic diagrams of radar and the essential formula,

tables, data. In Topic 1 – Topic 4, Topics 6, and 7, in accordance with the specific

competence requirements and teaching needs, a syllabus of the demonstration and

practical training is available, including the training objectives, training mode and

training procedure. The instructor should note that the required performances in

Topics 5 and 6 involve comprehensive and systematic theoretical knowledge and

practical training and it is impractical to recommend demonstration and practical

training for Topic 5 separately. Therefore, the demonstration and practical training in

Topic 6 is designed for both topics as a whole.

Assessment techniques: The course developer provides constructive assessment

techniques. Assessment builds a link between the "knowledge, understanding and

proficiency" and "criteria for evaluating competence "in table A-II/1 of the STCW Code.

However, assessment techniques reflect the "methods for demonstrating

competence" in column 3 of table A-II/1. Assessment techniques not only clarify the

objectives which should be contained in the assessment so as to help the instructor

conduct teaching tasks based upon them, but also give suggested approaches on

how to examine whether a trainee satisfies the required performances which include

written examinations, oral tests, practical operations, class discussions and records,

etc.

Teaching guidance: On the basis of the detailed instructor manual, key points and

difficulties in teaching are analysed and reasonable solutions are provided. Especially

for the sustainable development of the nautical technology and safe navigation,

constructive and prospective teaching recommendations are given regarding teaching

notions, teaching methods, teaching skills, etc. Practical teaching methods and

techniques are also provided for better utilization of the model course. Instructors are

suggested to have a thorough knowledge and comprehension of this part and apply

this throughout the course.

Detailed instructor manual

A detailed manual, consistent with Parts B and C, is as follows.



1 Basic theory and operational principles of marine radar systems

Detailed teaching packages

The contents of this topic include the principles of the range and bearing

measurements of the marine radar, the basic configuration and operation of the radar,

the performances and their influence factors, and the factors leading to the

misidentification and misinterpretation of the radar picture.

This topic is the foundation of this course. Adequate understanding of this part is

essential to comprehend and utilize the information obtained from the radar and

ARPA or Target Tracking (TT) and AIS to maintain look-out, observe, fix positions,

carry out navigation and avoid collision.

1.1 Fundamental principles of radar

The target's position relative to the own ship is determined by the plotted range and

bearing. On this basis, radar can provide the functions of keeping look-out,

observation, position-fixing, navigation and collision avoidance.

.1 Principles of range and bearing measurement

(1) Range measurement

If the transmitted pulse round-trip time of between the antenna and a target is Δt and

the electromagnetic wave traveling velocity in free space is C, then the range is,

2S C t (1-1)

(2) Bearing measurement

A Radar antenna is a rotating directional scanner with a horizontal beamwidth of only

one to two degrees. At a given moment, therefore, radar can transmit electromagnetic

waves in only one direction and at the same time it can simultaneously receive echo

returns in the same direction. The scanner rotates at a very constant speed (about 20

to 30 r/min). When the scanner receives the echo returns from one direction, the

target would be recorded in the same bearing unit in the display. The relative bearing

of the target is the angle measured clockwise from the heading line of the screen to

the target echo.

On the advanced radar display, range and bearing measurement is based on CCRP.

According to the Revised Recommendation on Performance Standards for Radar

Equipment annexed to IMO MSC. 192(79) (hereinafter referred to as resolution

MSC.192(79), Performance Standards), the CCRP is the location on the own ship, to



which all horizontal measurements such as target range, bearing, relative course,

relative speed, CPA and TCPA are referenced. Where multiple antennas are installed,

there should be a provision for applying different position offsets for each antenna in

the radar system.

The difficulties in this sub-topic such as the concepts of the antenna horizontal

beamwidth, the CCRP and the theory of bearing measurement, can be explained with

slides, Flash, etc. It is suggested that the instructor be informed how the trainees

understand the concepts of CPA, TCPA before the class, and give a brief explanation

in class if necessary.

.2 Configuration of marine radar system

The system configuration of a marine radar satisfying resolution resolution

MSC.192(79), Performance Standards is shown in Fig.1-1, in which the parts with

equal dotted lines are not mandatory but optional.

The main EPFS provides data of the WGS-84 position and UTC time to the radar

system; the gyrocompass or the Transmitting Heading Device (THD) supplies

heading; the Speed and Distance Measuring Equipment (SDME), usually the speed

log, provides the own ship speed; and the radar sensor provides image information of

the sea surface around the own ship. To be specific, the functions of radar Information

processor and display system include presenting processed images, tracking targets

and obtaining the targets' parameters. The Automatic Identification System (AIS)

provides static and dynamic information of surrounding ships and data of navigation

aids. The Voyage Data Recorder (VDR) records voyage data. The optional Chart

Radar functionality provides a coordinated display that integrates radar and ENC

data.

This sub-topic can be taught by referring to the marine radar system configuration as

shown in Fig.1-1. Note that the part within the equal dotted lines is not the standard

configuration but is optional.



.3 Composition and principles of basic radar

The composition of a basic radar is shown in the block diagram in Fig.1-2 which is

also the radar equipment satisfying the performance standards prior to resolution

MSC.192(79) PS. It mainly consists of seven parts: the trigger generator, the

transmitter, the duplexer, the antenna, the receiver, the information processor and

display system and the power.

(1) Trigger generator: to generate trigger pulses (Timing signal);

(2) Transmitter: to generate recurrent and high-frequency pulses;

(3) Duplexer: to transmit pulses to the antenna when transmitting;

to receive echoes to the receiver when receiving;

(4) Antenna: to transmit and receive the radar's electromagnetic waves;

(5) Receiver: to amplify and process the received signal;

(6) Information processor and display: for radars that comply with resolution

MSC.192(79), Performance Standards, the information processor processes

information, tracks targets from sensors, displays target information from the radar

Antenna

Duplexe

r

Transmitter

Timer

Power Receiver

Display

Fig.1-2 The block diagram of a basic radar

component

Ship power

VDR

Information processor and display system

ENC/other vector chart

display system

AIS antenna

Gyro/THD

Fig.1-1 Radar system configuration

Transceiver Main unit

AIS

Main unit

Main EPFS

SDME

Basic

rad

ar s

yste

m

Antenna



and AIS. For radars that do not comply with resolution MSC.192(79), Performance

Standards, this unit is only used as the information display and operation terminal;

(7) Power: to convert ship's power into radar power.

Demonstration and practical training 1-1 Demonstration of radar system configuration and installation location on baord

1.2 Magnetic safe distance

The magnetism caused by radar parts leads to compass deviation. In order to avoid

affecting the accuracy of the magnetic compass, a safe distance of more than 2.5 m

should be kept between the radar parts and the magnetic compass, especially for the

distance between the magnetron and the magnetic compass. The instructor can

illustrate the relationships between the radar parts and the magnetic compass by

showing their positions on the real ship bridge.


The peak power of the radar's radiation, usually 2~30 kW, is very high, but the

average power is very low. On board, the microwave radiation is tiny when people are

away from an antenna for more than 20 m, and not in the radiation centre of the

antenna's vertical beam. If this does not involve a prolonged close-range radiation

exposure, the harm of the radar to the human body can be ignored.

When some support boats (pilot boat, tug, etc.) are approaching, the own ship's radar

should be switched to standby mode temporarily.

The instructor must give a clear explanation of peak power to the trainees, and

demonstrate the characteristics of the peak power as it decays with the increasing

distance. Real ship photos of the radar antenna location can be utilized to illustrate

the above contents.


.1 Maximum detection range of target

In free space, the farthest distance that radar is able to detect a certain target is called

the radar's maximum detecting range of target.

.2 Minimum Detection range

The minimum detecting range is the nearest distance at which a radar can identify a

target, which represents the radar's capability to detect short range targets.



.3 Effects on range and bearing accuracy of synchronization error, Consistent Common Reference Point (CCRP) error, pixel/spot size, and pulse length, variable range marker error, HBW, heading marker error, centring error, and THD error

(1) Range accuracy

The main factors impacting radar range accuracy are as follows:

(a) Time synchronization error: Time synchronization error occurs if the time when the

transmitting pulse leaves the radar radiation window is different from the position of

"0" nm scanned on the screen or recorded by the echo return. Under appropriate

conditions, the error should be checked whenever necessary;

(b) CCRP error: The setting of CCRP offset should be made when the radar is

installed and can be adjusted on voyage. The inaccuracy of CCRP offset adjustment

would bring range error relative to the CCRP;

(c) Pixel/spot size error: Pixel should not be neglected to range error especially when

the range is set at long ranges;

(d) Pulse length error: While measuring a target at long range, the echo trailer

generated by pulse length has a severe effect on trailing edge range accuracy. The

application of FTC while measuring a target's trailing edge can improve range

accuracy;

(e) Measurement instrument error: RRs (range rings) and VRM have their own errors

which should be adjusted every voyage or month (whichever is shorter). For the radar

that satisfies the latest performance standard, this regular adjustment is not

necessary.

(2) Bearing accuracy

The main factors impacting the radar bearing accuracy are as follows:

(a) Bearing synchronization error. The error occurs when the radar antenna bearing

data is transferred to information processor and display system.

(b) Beam width error. Horizontal beam width (HBW) is one of the main factors

affecting radar bearing accuracy.

(c) Heading marker and THD errors: They affect the target relative and true bearing

accuracy.



(d) Centring error: For the PPI, if the radial scan centre is not completely consistent

with the screen centre, it may cause bearing error.

(e) Pixel error: The echoes can expand 1 pixel at most to the right and left sides due to

the pixel effect, with greater influence on the bearing accuracy than on the range

accuracy.

(f) CCRP (consistent common reference point) error: The inaccuracy of CCRP offset

adjustment would cause bearing error relative to the CCRP.

.4 Effects on range and bearing discrimination of HBW, pixel/spot size, range scale, pulse length, gain, and information processing

(1) Range discrimination

Range discrimination refers to the radar's capability to distinguish two adjacent targets

on the same bearing as shown in Fig.1-4, and it relies on:

(a) Pulse length: pulse length is one of the main

factors affecting the range discrimination. The

pulse length of 1 μs can cause 150 m radial

extent along with the trailing edge;

(b) Pixel/spot size: the size of screen pixel is

another main factor affecting the range

discrimination. The longer the range scale, the

greater the influence on the range

discrimination caused by the pixel size;

(c) Information processing: for an early processing system, the distortion due to the

receiver signal processing includes the transmission bands distortion, the nonlinearity

distortion, and the quantification distortion which make the leading and trailing edges

of the echo blur and have a certain effect on the range discrimination;

(d) Gain: proper gain reduction improves the range discrimination.

(2) Bearing discrimination

Bearing discrimination is the radar's capability to distinguish two adjacent point targets

with the same range on the screen. The performance standard is expressed by the

minimum intersection angle of the two adjacent point targets at the same range, as

shown in Fig.1-5. It relies on:

Range discrimination

Pix

el d

isto

rtion

P

rocessin

g d

isto

rtion

Targ

et A

Fig.1-4 Range discrimination

Pro

cessin

g d

isto

rtion

Targ

et B

Puls

e le

ngth

Scre

en p

erip

hery



hA

hT

Fig.1-6 Radar standard detection horizon

Sea surface horizon

Radar horizon

Target horizon

T

(a) HBW: the echoes expand to the right and left

sides with the difference of the targets' distances

and the difference of the targets' echoes strength.

For long range, weak small targets, the radar's

bearing discrimination becomes half the size of the

actual echo (>θH/2).

For short range targets with strong reflection, the

echo expansion becomes twice the size of the actual echo (> 2θH).

For short range strong targets, the radar's bearing discrimination would diminish.

(b) Pixel/spot size: the size of the screen pixel causes the echoes to expand to left

and right sides up to 1 pixel size.

(c) Range scale: the bearing discrimination is poor for targets in short range.

(d) Gain: appropriate gain reduction can improve the bearing discrimination.


.1 Effects of antenna height on detection ranges

As shown in Fig.1-6, under standard atmospheric conditions, the radar beam tends to

bend slightly downward to the sea surface, and the theoretical maximum detection

range for the target T is given by the formula:

max 2.2( )a tR h h (1-5)

Where ha and ht are the heights of the antenna and the targets respectively in metres.

And Rmax is the theoretical maximum detection range affected by the earth's curvature

in nautical miles.

The instructor should illustrate to the trainees that formula (1-5) is an engineering

application formula in navigation. It will deviate because of the change of the

atmospheric condition any time. Suggest this formula be used to estimate Rmax.

A

Fig.1-5 Bearing discrimination

B

H

H

Pixel size expansion

Bea

ring d

iscrim

ina

tion



.2 Effects of atmospheric conditions on detection ranges (super-refraction, sub-refraction, surface duct, elevated duct)

The instructor may first state the concept of refraction with the help of teaching

apparatus or models, such as prism and glass container filled with water. This section

demonstrates radar detection horizon in the atmosphere propagation in non-standard

atmospheric conditions.

(1) Super-refraction

In calm weather, when the humid hot air over the continental area flows up over the

sea, with the increase altitude, the temperature increases but humidity decreases

sharply. This will cause the electromagnetic wave propagation velocity to increase,

and the electromagnetic wave propagation path to bend to the sea surface more

seriously than normal propagation. This phenomenon is called super-refraction, as

shown in Fig.1-7. As super-refraction occurs, the radar detection horizon would be

greater than normal.

Super-refraction often occurs in tropical and other hot continent areas, such as the

Red Sea, the Arabian Gulf, the Mediterranean Sea and the English Channel in the

summer.

(2) Sub-refraction

In calm weather of the opposite meteorological conditions with the super-refraction

when the temperature of the atmosphere decreases more rapidly as the height rises

than in standard atmospheric conditions, or the increase of relative humidity as the

height rises sharply, sub-refraction will occur, as shown in Fig.1-8.

When sub-refraction occurs, the wave beam departs from ground higher and higher,

Fig.1-8 Sub-refraction

Sub-refraction horizon

Standard horizon

Cold wet air

Warm dry surface

Fig.1-7 Super-refraction

Warm air

Super-refraction horizon

Sea surface

Standard horizon



and it may result in the radar not being able to detect the original targets which can be

detected in the standard refraction. The original targets within the radar detection

horizon on the sea surface may be undetectable when serious sub-refraction occurs.

Sub-refraction often occurs in the Polar Regions and the vicinity of very cold

continents. When cold air masses over the continent move over warm ocean surface,

also known as "cool up and warm down" and "wet up and dry down" situations, the

sub-refraction phenomenon can be observed.

In late winter and early spring seasons in the mid-latitude regions, when the weather

is clear after the snow and cold air over the continent moves over the sea surface,

sub-refraction phenomenon can also be observed.

The features of sub-refraction are as follows:

(a) Temperature decreases more sharply with the increase of altitude than in normal

atmospheric condition;

(b) Relative humidity increases sharply with the increase of altitude;

(c) Sub-refraction often occurs in the polar regions and adjoining very cold continents.

(3) Surface duct

As shown in Fig.1-9, when serious super-refraction occurs, surface duct occurs, that

is, radar wave is refracted to the sea surface, then refracted to the atmosphere, and

then refracted to the sea surface from the atmosphere.



(4) Elevated duct

In calm weather, a layer of cold air over the warm sea surface appears at the height of

the radar antenna, as shown in Fig.1-10. The radar wave, which is reflected by the

layer between the cold air and the warm air, may travel a far distance and detect very

long range targets, but cannot detect targets close to the sea surface clearly. This

phenomenon is known as elevated atmospheric duct. This duct phenomenon does

not occur frequently in all directions, and has a relationship with the radar's working

wavelength.

The elevated duct usually appears seasonally in the trade wind regions between

mid-ocean water of high atmospheric pressure and the doldrums, such as the waters

between Brazil and Ascension Island and between southern California and Hawaii,

etc.

The features of elevated duct are as follows:

(a) There exists a reflecting layer of warm air (inversion layer) above the sea in

peaceful weather;

(b) Antenna height is in reflection level;

(c) It normally appears seasonally in the trade-wind zone between high pressure

zones and Inter Tropical Convergence Zone (ITCZ).

.3 Effects of precipitations on detection ranges (rain, hail, snow, fog)

During the process of atmospheric propagation, the absorption or scattering of dust

haze and water vapour in the atmosphere will cause the attenuation to radar wave

Sea surface

Low clouds

Breeze

Cold air

Standard horizon Super-refraction horizon

Fig.1-9 Surface duct

Warm air

Fig.1-10 Elevated duct

Warm surface

Warm air

Cold air



energy. The attenuation to radar waves due to rain or snow will increase with the

increase of raindrop and rain density, and lead to the decrease of the maximum

detection range. References indicate that attenuation due to rain or snow for 3 cm

wavelength is about 10 times larger than 10 cm wavelength.

.4 Blind and shadow areas, permanent blind and shadow sectors and their relationships with antenna location

This part can be illustrated through the use of real ship radar pictures (e.g. Fig.1-11(c))

and an actual antenna.

Sheltered by obstacles or ship super-structures, shadow sectors are known as areas

where detecting ability is reduced or even targets cannot be detected.

The antenna radiation window has a dimension with a radiation beam width of 1°~ 2°,

and radar wave has certain diffraction capabilities, therefore, it is probable to detect

targets within the shadow sectors. Radar may detect no target in the centre of the

shadow which is called the blind area in shadow sectors. The other areas where radar

detecting ability is reduced are known as the sensitivity reduced arcs in shadow

sectors. The ship structures such as forecastle, foremast, cross tree, mainmast,

funnel and poop, etc. impose effects on radar observation permanently and affect

navigation safety, as shown in Fig.1-11 (a) and (b). Radar picture of Fig.1-11 (c)

shows the influence of blind sectors caused by the ship's mainmast and the funnel on

radar observations.

The size of a shadow sector is determined by the size of obstruction, the distance of

the obstruction to the antenna, the relative height of the obstruction to the antenna,

and the antenna size.



The higher the obstruction, the larger the measurement, the closer the distance to the

antenna, and the larger the shadow sector; the location of the radar antenna should

be carefully considered prior to installation. In accordance with IMO radar installation

guidelines, blind sectors should be kept to a minimum, and should not be placed in an

arc from right ahead to 22.5° abaft the beam on its respective side. Within the

remaining azimuth, individual blind sector of more than 5°, or a total arc of blind

sectors of more than 20° should not occur.

.5 Influences of target characteristics on detection ranges (aspect, shape, composition, size)

Different targets have different reflective characteristics. A good understanding of the

features of target contributes to quick and accurate target identification in complex

observation environments, and for effective radar position-fixing, navigation and

collision avoidance.

The feature of the electromagnetic response of the target under radar beam radiation

is called the target characteristics. The target is detected by receiving the reflective

radar wave. Thus the ability of the target reflecting radar wave will affect radar

observation. Normally, the target radar cross-section (RCS) represents the capability

of a target reflecting radar wave.

Shadow sectors Shadow sectors

(b) Side view

VBW

Fig.1-11 Shadow sector

(c) Radar image of shadow sector

Shadow sectors

Sea clutter

Sensitivity reduced arc

Blind area

(a) Top view

Sensitivity reduced

arc

blind area



The RCS of the target is related to many factors, including target composition, shape,

aspect, structure, size, radar aspect and radar wave length, etc.

In class, the instructor can demonstrate the influences of the aspect, shape,

composition, size to the radar detection range by radar screen shots.

(1) Aspect and shape

(a) Aspect

The angle between incident radar beam and target surface (0°～90°) is known as

radar aspect.

(b) Target shape

With respect to radar wavelength, the surface of target is rough.

Any complex target at sea can be seen as a combination of several protocol

geometric objects. Spherical targets have poor reflective performance; especially the

spherical targets with smooth surface. Only a small portion towards the waves can

reflect the echoes. When the sphere has a rough surface, the response is slightly

better. Cylinder targets such as funnel, gas/oil tank and mooring buoys, only a small

portion towards the waves contributes to response. The specific echo intensity

depends on its size and aspect. Cone targets, such as beacons, church steeples and

conical buoys, have very poor reflective performance. Only when the radar wave is

perpendicular with the generatrix, the reflect performance is the same as cylindrical

targets. A conical buoy in seaway will roll, so the echoes may fluctuate.

(2) Target composition

Usually, materials with good electrical conductivity will produce good radar responses.

This occurs as a result of absorption and re-radiation of the waves of the same

wavelength as those received, rather than from simple specular reflection.

(3) Target size

The radiation cell is defined by the transmitted pulse length of the radar radiation

beam.

(a) When the target area towards radar beam is less than the intersecting surface of

the radiation unit, the strength and size of echoes are proportional to target width and

height.



(b) When the target area towards the radar beam is greater than the intersecting

surface of the radiation unit, the strength of echoes does not relate to target width and

height. The shape of echoes is determined by the horizontal projection of the target

towards the antenna.

.6 Influences of clutter and interference (sea clutter, rain clutter, radar interference)

(1) Sea clutter

The causes of sea clutter are shown in Fig.1-12.

The features of sea clutter are:

(a) Created by sea waves and their random and systematic movements;

(b) More problematic at shorter ranges, decreasing in intensity with range;

(c) Typically stronger to windward and weaker to leeward;

(d) Range extends out to about 3 to 6 nm; 8 to 10 nm in rough seas;

(e) The higher the antenna, the stronger the clutter and the further its range;

(f) Clutter of the 3 cm radars is stronger than 10 cm;

Clutter from wide pulse is stronger than narrow pulse.

(

(h) Clutter is strong or when the horizontal beamwidth is wider.

A

A C

C

A

Rmin

θH

θv

Fig.1-12 Sea clutter

(a) Front view

(b) Top view

Wind direction

Windward Strong echoes

Short range Strong echoes

Leeward Weak

echoes

No clutter

Pulse length



(2) Rain clutter

Rain attenuates the radar wave and also reflects it back as an echo that affects

normal radar observation. The strength of the response is proportional to the rainfall.

Rain echoes are shown in Fig. 1-13.

The features of rain echoes are as follows:

(a) Echo strength is proportional to precipitation;

(b) Responses are fluffy bright specks

with no obvious edge;

(c) Under tropical rainstorm-like

conditions, radar detection of targets is

seriously compromised;

(d) Rain clutter on 3 cm radar radar is

stonger than 10 cm;

Rain clutter from wide pulse is stronger

than narrow pulses.

(f) Stronger when the horizontal

beamwidth is wider.

The instructor should demonstrate to the trainees the screen shots with and without

rain clutter.

(3) Radar interference

Radar interference is generated when the radar receives signals from other radars of

the same or similar frequency.

Radar interference causes random effects which do not tie up with the regular image

on the radar display. It is "non-correlative", while the target echoes are "correlative".

The interference image can take any form but frequently have a spiral character within

the operational display area. Interference can be received by the main lobe of the

radar antenna and its sidelobes. Also the transmissions can come from both the main

lobe and sidelobes of the interfering radar.

In this section, video demonstrations of sea and rain clutter should have a positive

effect on teaching and learning.

Rain clutter

Target

Fig.1-13 Rain clutter




.1 Causes and effects of indirect echoes

Radar waves can be blocked by the obstructions such as superstructures including

masts, funnels, cross-trees, deck cargoes, deck cranes, ventilators on board or a

large vessel in the vicinity or tall buildings on shore.The shadow arcs are engendered

behind these obstructions. These obstructions can also reflect radar waves like

mirrors to other directions. One target may produce two echoes on the radar screen.

As shown in Fig.1-14, A and B are the true target echoes, while A' and B' are indirect

false echoes.

(1) The features of indirect false echoes are:

(a) The indirect false echo of the target appears in the shadow sector;

(b) The range and bearing of indirect false echoes are different from its real echo. The

azimuth of obstacles is the bearing of false echoes and the range is the sum of both

distances of the obstacle to the target and obstacle to the antenna;

(c) The strength of indirect false echoes is weaker than the real echo, and false

echoes often have significant distortion in shape;

(d) The motion of false echo is not like the real echo movement.

By altering the ship's course, indirect false echoes will disappear or still be in the

shadow sector and can be identified. They can be suppressed or eliminated by

decreasing gain temporarily or using FTC (Fast Time Constant) appropriately. .

B A

Fig.1-14 Indirect echo

A B

B

Real target

False echo No AIS symbol

False echo

A



.2 Causes and effects of multiple echoes

As shown in Fig.1-15, radar energy bounces back and forth between the target and

the observing ship, with some of the energy entering the antenna at each return.

Multiple false echoes may thus occur. This phenomenon often happens when two

ships navigate in parallel in narrow waters, such as a narrow channel or anchorage.

The features of multiple echoes are as follows:

(a) They occur in the same direction beyond the true echo with the same interval. The

spacing equals the range of the true echo;

(b) Strength becomes weaker with the increase of range;

(c) False echoes move with real echoes.

It is easy for observers to identify multiple echoes, and they can be suppressed or

eliminated by decreasing gain or using FTC appropriately.

.3 Causes and effects of side lobe echoes

Radar side lobe radiation is relatively weak and generally never affects the

observation of long range targets. However, for close range strong echoes, side lobe

radiation cannot be ignored. Radar side lobe false echoes mainly refer to the false

responses caused by the primary side lobe radiation.

In recent years, the capability to detect small targets by the improved radar receiver

has been greatly improved, while the capability to suppress antenna side lobe

radiation has not. As a result, the capability of side lobe reception has been enhanced.

Therefore, some modern radar equipment may detect the false echoes by secondary

side lobe radiation, namely side lobe indirect false echoes and side lobe multiple false

echoes.

Own ship Target ship Real echoes

False target

Fig.1-15 Multiple echoes



(1) False echoes from primary side lobe radiation

Side lobe echoes, associated with close range targets, result from the radar beam

being surrounded by side lobes. As shown in Fig.1-16, side lobe echoes are

distributed and dispersed on the arc of the genuine echo on both sides.

Side lobe echoes may appear frequently for smaller size antenna, especially when the

surface of the radiation window is dirty or damaged.

The features of the side lobe echoes are:

(a) Side lobe echoes symmetrically distribute on the sides arc of the real echo;

(b) All side lobe echoes will be at the same range as real echoes, with neighbouring

bearing;

(c) As side lobe echoes are much weaker than real echoes, it is a little difficult to

distinguish a whole real echo under the interference of side lobe echoes;

(d) Under strong wave conditions, side lobe radiation will increase sea clutter effects,

and seriously affect radar close range observation.

It is easy to identify side lobe echoes and use the gain or anti-clutter controls

(STC/FTC) to suppress or eliminate the weaker side lobe echoes.

Two small targets

B

A

Real echo

A

B

Fig.1-16 Side lobe echoes

Side lobe echoes Side lobes

Main beam



(2) False echoes from secondary side lobe radiation

The false echoes caused by secondary side lobe radiation are very similar to indirect

false echoes and multiple false echoes from the main lobe, as shown in Fig.1-17.

Because the capability of modern radar receiver to detect weak signals is

continuously improving, some radar side lobe radiation and reception can also detect

false echoes of short range and strong targets due to secondary side lobe radiation,

namely, side lobe indirect false echoes and side lobe multiple false echoes. But the

side lobe radiation is about 20 to 30 dB weaker than main lobe radiation, compared

with normal radar echoes, false echoes by secondary side lobe radiation are usually

much weaker. This is often accompanied by main lobe indirect false echoes and main

lobe multiple false echoes at the same time, making the radar picture confusing.

The instructor can explain the effects of radar receiving by side lobe indirect false

echoes by use of Fig.1-17. In this illustration, A' is the schematic diagram of side lobe

indirect false echoes. It should be noted that the secondary side lobe indirect false

echoes have rare occurrences and can be observed occasionally only in a few high

gain receiver systems, and they are mostly side lobe indirect false echoes.

.4 Causes and effects of second trace echoes

Under super-refraction conditions, the radar energy travels to greater distances than

under normal atmospheric conditions. This means that echoes from long range

targets can be detected from the distance exceeding pulse repeat period, and the

echoes are displayed on the "second trace". As shown in Fig.1-18, the return from a

target situated beyond the maximum displayed range may be received after the next

pulse has been transmitted. It can be erroneously displayed as a target at a much

shorter range. It is generally termed the "second trace echo" effect.

A

Fig.1-17 Secondary side lobe echoes

A

A



The features of second trace echoes are as follows:

(a) The bearing of second trace echoes is right, but displays distance which is less

than the actual distance of the target.;

(b) The second trace echoes will have a distortion compared with the actual target.

For example, an echo of straight shoreline at long range is displayed as "V" picture;

(c) If range selection changes, range of false echoes will change, distort or disappear;

(d) The movements of second trace echoes are unreasonable on the screen.

It can be observed that the motion of the echo is abnormal in the display by changing

the range scale to identify the false echoes.

Fig.1-18 Principles of second-trace echo

Trigger

T

Tx pulse

Echo

Sweep

RRs

Echo of previous transmitting pulse

1 2



.5 Effects on radar picture of power lines, bridges crossing rivers and estuaries, low altitude aircrafts

An overhead power cable crossing a water channel typically creates a very unusual

effect in a radar. This is because it acts as a smooth reflector and a ship's radar will

typically only receive a return when the beam from the radar is exactly orthogonal (at

the right angle) to the geographical line that the cable follows. The resultant single

point echo leads to a collision risk situation on the radar display no matter how the

ship manoeuvres. For easy identification, some radar reflectors are installed on the

cable at intervals. Due to bearing discrimination, it is possible that the echoes of

reflectors look like the dyke-dam blocking up the channel for radar of very strong

detecting ability. Fig.1-19 shows the echo of this situation.

Low altitude aircraft may also be detected by radar, presenting a quick jumping echo

on the screen. If it is acquired by radar target tracking, the lost target alarm may arise

after a short period.

.6 Effects of ships in seaway

The pitching and rolling of a ship may lead to echo glint and the edge of the echo is

blurred. Weak echoes appear flickering on the screen.

1.7 Performance standards for radar equipment in Resolutions MSC. 192(79), Annex 4 of MSC. 64(67) and A. 477(XII)

This sub-topic can be discussed separately; or in combination with Sub-Topic 1.4.

This helps the trainees to develop an understanding of the subject knowledge and

radar performance standards.

Fig.1-19 Echoes of an overhead cable across channel

Echoes of cable

with radar

reflectors



.1 Requirements for detection ranges (long and short ranges)

① Minimumrange

Under normal propagation and in calm conditions, when the radar antenna is mounted

at height of 15 m above sea level, a minimum range is showed as Tab.1-1.

Tab.1-1 Minimum detection ranges

(1) The requirement for detection range in resolution MSC.192(79),

Performance Standards

(a) Minimum range

In the absence of clutter, for long range and shoreline detection, the requirement for

the radar system is based on normal propagation conditions, in the absence of sea

clutter, precipitation and evaporation duct with an antenna height of 15 m about sea

level, and based on an indication of the target in at least 8 out of 10 scans or

equivalent and a probability of a radar detection false alarm of 10-4. The minimum

detection ranges in clutter-free conditions are shown in Tab. 1-2.

Tab.1-2 Minimum detection ranges in clutter-free conditions

Target description Detection range (nm)

Type Height above

sea level (m) X band S band

Shorelines 60 20 20

Shorelines 6 8 8

Shorelines 3 6 6

SOLAS ship (>5,000 GT) 10 11 11

SOLAS ship (>500 GT) 5.0 8 8

Small vessel with radar reflector 4.0 5.0 3.7

Navigation buoy with corner reflector 3.5 4.9 3.6

Typical navigation buoy 3.5 4.6 3.0

Small vessel of length 10 m with no radar reflector 2.0 3.4 3.0

With the own ship at zero speed, an antenna height of 15 m above the sea level and

in calm conditions, the navigational buoy in Tab.1-2 should be detected at a minimum

horizontal range of 40 m from the antenna position and up to a range of 1 nm, without

changing the setting of control functions other than the range scale selector.

Target Description Detection Range (nm)

Shoreline, when the ground rises to 60 metres 20

Shoreline, when the ground rises to 6 metres 7

A ship of 5000 tons gross tonnage, whatever her aspect 7

A small ship of 10 m in length 3

A navigation buoy having an effective echoing area of approximately 10 m2 2



Compensation for any range error should be automatically applied for each selected

antenna, where multiple antennas are installed.

(2) The requirements for detection range in the Annex 4 of resolutions

MSC. 64(67) and A. 477(XII) PS

(a) Long range targets

Under normal propagation and in calm conditions, when the radar antenna is mounted

at a height of 15 m above sea level, a minimum range is showed in Tab.1-1.

Tab.1-1 Minimum detection ranges

(b) Short range targets

The surface objects specified in Tab.1-1 should be clearly displayed from a minimum

range of 50 metres up to a range of 1 nm, without changing the setting of controls

other than the range selector.

.2 Requirements for accuracies (range and bearing)

The radar system range and bearing accuracy requirements are shown in Tab.1-3.

Tab.1-3 The range and bearing accuracy

IMO Resolution Range Accuracy Bearing accuracy

MSC. 64(67)

MSC. 192(79) ≤30 m or 1% of the range scale in use, whichever is greater. ≤1°

A. 477(XII) ≤70 m or 1.5% of the range scale in use, whichever is greater. ≤1°

Target Description Detection Range (nm)

Shoreline, when the ground rises to 60 m 20

Shoreline, when the ground rises to 6 m 7

A ship of 5000 tons gross tonnage, whatever the aspect 7

A small ship of 10 m in length 3

A navigation buoy having an effective echoing area of approximately 10 m2 2



.3 Requirements for discriminations (range and bearing)

The radar system range and bearing discrimination requirements are shown in

Tab.1-4.

Tab.1-4 The range and bearing accuracy

Demonstration and practical training 1-1 Demonstration of radar system

configuration and installation location on board

(1) Training objective

The contents of this topic include the basic theories and operational principles, and

this topic is the foundation of this course. Through this topic, the instructor can help

trainees to understand radar system configuration and installation location of a basic

radar, and to be familiar with basic information of radar picture.

(2) Training mode

Use a live radar or radar simulation adopt other teaching methods, for example,

videos, etc.

(3) Training procedure

(a) Demonstrate radar configuration, including antenna, transceiver, display system,

T/R switch and power supply, THD, SDME, EPFS, AIS, ENS and VDR.

(b) Demonstrate the installation location of the radar components on board.

(c) Demonstrate the radar echoes, heading line, EBLs, VRMs and RRs, CCRP.

Assessment techniques

Assessment upon completion of the topic can be conducted in the forms of written

examination, oral test, discussions, demonstrated practical assessment and class

records, etc. in order to assess whether a trainee satisfies the required performance.

Focusing on the fundamental principles in this topic, the trainee should

Resolution Conditions Range discrimination Bearing discrimination

MSC.

64(67)

MSC. 192(79)

In calm sea conditions, on a range scale

of 1.5 nm or less and at between 50%

and 100% of the range scale selected.

40 m 2.5°

A. 477

In calm sea conditions, on a range scale

of 2 nm or less and at between 50% and

100% of the range scale selected.

50 m 2.5°



(1) acquire the knowledge of radar system configuration, radar installation location

and the fundamental principles of a marine radar system;

(2) understand the radar performances and factors affecting them;

(3) identify the information derived from the radar picture correctly; and

(4) be aware of the factors that may lead to misinterpretation of the radar picture.

Teaching guidance

With the development of navigation technology and information innovation, the radar

is no longer a stand-alone observation unit but rather an integrated navigation

information system which performs multiple functions including position-fixing,

navigation and collision avoidance based on important navigation information from

sensors. In this regard, as required in the performance standards of Integrated

Navigation System (INS), the radar system has the primary functions of INS. The

instructors should be well aware of the change and impact on radar navigation training

and lead the trainees to build up the concept of radar navigation from an information

navigation perspective.

The fundamental principles of a marine radar system are the basis of this course and

a prerequisite for trainees to develop a proper understanding of radar and ARPA

information for position-fixing, navigation and collision avoidance, and put it into use.

Radar transmitters have long adopted magnetron-based technology. The latest

revised IMO radar performance standards MSC. 192(79) no longer requires that 10

GHz band radars have the ability to detect active radar beacons. This actually means

innovation design of 10 GHz band radars is encouraged.

Radar transmitters that are based on solid state technology rather than magnetrons

are becoming increasingly fitted to all class of vessels. These transmit much longer

pulses than magnetron-based radars to compensate for the much lower peak powers

that are used. Special processing is automatically applied that results in a radar image

that is at least as good as that of a conventional magnetron-based radar. In principle,

such radars can offer improved performance than conventional systems, especially in

sea and rain clutter, although advanced magnetron-based systems are also able to

offer similar benefits. This is because the received signal is analysed in terms of both

amplitude and phase, whereas a conventional radar only processes the amplitude of

the received signal.

Solid states radars that meet the requirements of the IMO have very similar controls to

that of conventional radars and can be operated with a similar mind-set, even though



there are differences in the way that the radars operate internally. They basically work

on a principle known as pulse compression, which effectively converts the received

long pulse into an equivalent short pulse from a conventional radar. With this in mind,

the guidance contained here, which is concentrated toward conventional

magnetron-based radar operation, is also appropriate for the skilled use of solid state

radars. When pulse length is mentioned it should be appreciated that, for a solid state

radar, it applies to the compressed pulse length and not the transmitted pulse length.

Some of the controls simulate those of a conventional radar to aid the operator's

familiarity but in practice can work on a different basis to that described. This is also

the case for some magnetron-based radars. These include gain, tuning and manual

sea and rain clutter settings. However, the user can assume that very similar effects

to those described in this Model Course result from the use of such controls but, in

principle, may provide more effective results in difficult situations.

As an important component of INS, the sensor system which provides course, speed,

position and timing to the radar system should adopt the same Consistent Common

Reference System (CCRS) with other integrated information processing terminals so

that the operator can acquire consistent information from different displays. It is

advised that the instructors should highlight the indispensable role of the marine radar

system in safe navigation in the context of information navigation with GNSS as the

cornerstone and AIS as the trigger.

With the ever-increasing contradiction between shipping development and navigation

safety, higher standards for radar sensor systems are adopted. Azimuth stabilized

presentation modes are essential to ensure the proper operation of a digital

information processing system in a modern radar. Hence, the officer in charge of a

navigational watch has no choice but to use the azimuth stabilized presentations to

maintain safe navigation. The latest navigation technology provides abundant

multi-sensor information to a radar system. In accordance with IMO radar

performance standards, the speed sensor should provide the stabilized mode with

speed over ground and speed through water. It is advised that, in the course of

instruction, the instructor should interact with the trainees and explore the effects of

various speed modes on radar navigation and collision avoidance so that the trainees

can fully understand the necessity and complexity of speed mode selection for safe

navigation.

It is also advised that the instructor should facilitate the trainees in developing a

gradual understanding of the changes of radar performances, functions, operations

and applications in the trend of navigation informatization, on the basis of their

mastery of the fundamental radar principles. Furthermore, after the trainees have

learned the basic theory on measurement of target range and bearing by radar, the

instructor may, use teaching aids such as projectors, video and CBT, etc. to highlight

the significance of system sensors and its integrity to the safety of radar navigation.



In order to help the trainees achieve a better understanding of the fundamental

principles of radar, it is advised that the instructor should use live radar set as well as

videos to demonstrate the configuration of a radar system, the components of a basic

radar and the radar picture information.

The key points, requirements and teaching instructions of this topic include the

following aspects:

(1) Radar fundamental principles mainly include the principles of measuring target

range and bearing, radar system configuration, basic radar components and primary

information of the radar picture. Trainees are required to fully understand the

principles.

(2) Radar detection performances include maximum and minimum detection range,

range and bearing discrimination, range and bearing accuracy. Trainees should be

familiar with factors which affect these performances. In class, it is recommended that

the instructors make use of sketches, radar video recordings or pictures to help the

trainees to have a good understanding of the factors. Meanwhile, the following

aspects should be highlighted:

(a) The main factors affecting the maximum detected range are transmission power

and the receiver sensitivity.

(b) The main factor affecting the range accuracy is the time synchronization error.

(c) The main factor affecting the bearing accuracy is the bearing synchronization

error.

(d) The main factor affecting the range discrimination is the pulse length.

(e) The main factor affecting the bearing discrimination is the horizontal beam width

(HBW).

Moreover, it is necessary to remind the trainees of the significance in knowing how to

identify the long range target (beyond sea surface radar horizon) and short range

target (within sea surface radar horizon) by the radar detection horizon formula. It

might also be a good suggestion to incorporate Sub-topic1.7 into Sub-topic 1.4 to suit

practical needs.

(3) Radar false echoes include indirect false echoes, multiple echoes, side lobe false

echoes and the second trace echoes. Induction or tabulation teaching methodologies

might facilitate the trainees in understanding the causes, features, identification and

suppression of various false echoes.



(4) Radar clutter include sea clutter, rain clutter and radar interference. Trainees are

required to be familiar with features of the various clutter and their influences to radar

observation (The suppression methods will be discussed in Topic 2). Note that videos

and pictures showing the live radar observation scenarios at sea are very helpful for

the trainees to understand how the clutter/interference affect the radar observation.



This topic mainly introduces the basic methods of operating the main controls and the

general steps of switching on and off, the essentials of setting up and maintaining

optimum display, and the operations of measuring range and bearing accurately.

Radar operation directly affects observation, position-fixing, accuracy of navigation,

collision avoidance, and safety of navigation. A radar operator needs to accumulate

experience in a variety of navigational conditions, so that he/she can use the radar in

the observation, position-fixing, navigation and collision avoidance properly.

2.1 Setting up and maintaining optimum radar display

.1 Main controls (power, antenna)

The power control of radar includes the ship's power supply, radar power switch and

radar antenna safety switch.

Ship's power supply is usually set onto "ON" mode. Some sets are provided with a

heating system in each unit, when the set is not working, the ship's power will heat

them.

The radar power switch is usually located on the radar display unit. When the radar

power starts working, except the high-voltage power of the transmitter, all other parts

will be in working condition. After an automatic delay of about 3 minutes, time-delay

relay contacts will be closed. The transmitter goes into the standby mode and the

"STAND-BY" is indicated on the screen. The radar transmitter is ready to transmit.

The antenna safety switch is usually located at the antenna base. When the technical

staff maintains the equipment near the antenna area, this radar can be shut down, so

that it cannot be switched on from the operator panel and the safety of personnel is

ensured.



(1) Preliminary procedures

Ensure that the antenna is clear of obstacles; check that the ship's power supply is

working properly; set the brilliance, gain, automatic clutter controls to zero. Set the

range in medium or long scale.

(2) Switch on

Turn on the ship's power supply; then turn on the radar power switch. After the system

enters into the "stand-by" mode, the radar should be fully operational (RUN status)

within 4 minutes after switch on from the cold.

(3) Cautions

Do not turn on the power immediately after it has been turned off, wait several

seconds before the operator restarts the radar; Be sure to preheat the equipment in

the standby mode for 20 to 30 minutes before setting it into the transmit mode after

the magnetron has been replaced.

.2 Transmitter controls (transmission, pulse length, pulse repetition frequency)

(1) Transmit switch

The transmit switch is used to control the radar transmitter. When the switch is turned

from standby to active mode, the transmitter starts transmitting and the radar is fully

operational. When this switch is operated again, the radar returns to standby mode.

The following should be considered while using this equipment:

While on duty, it is best to use radars alternately. When the radar is not in use, it can

be set temporarily into standby mode, in order to prolong the service time of the

magnetron.

In a complicated navigational situation, such as restricted visibility and congested

waters which contain more navigational hazards and ships, it is suggested to use two

or more radars simultaneously. One is used for lookout, position-fixing, navigation and

the other for collision avoidance. The radar operator should select different range

scales to ensure the safety of navigation.

If out of service for a period of time, warming-up period must be extended in order to

remove the risk of dampness and ensure that the magnetron is fully preheated.



After the magnetron is replaced, the operator should strictly comply with the

magnetron preheating procedures and the preheating period must be more than

0.5 h.

Whether the ship is proceeding at sea or berthing, the radar is expected to be put into

Standby mode in order to reduce radar interference.

Solid state radars do not need preheating before transmitting.

(2) Pulse length

The pulse length selector is used to adjust the pulse length. A long pulse length can

be selected for long range scale to enhance the detecting ability. A short pulse length

can be chosen for a sharp image and good range discrimination.

The change of range will cause the change of pulse length and pulse repetition

frequency. Pulse length can be selected within 2~3 choices in the same range. The

short pulses are used on the short range scales and can be appropriately changed to

the longer ones, while the long pulses are used on the longer range scales and can be

appropriately changed to the shorter ones.

It is suggested that the instructor demonstrate the influence of pulse length on radar

observation by switching between different range scales.

(3) Pulse repetition frequency

Radars transmit short pulses on short range scales. The increase of the pulse

repetition frequency can gain on the accumulation numbers of pulse-echo, so as to

enhance echo intensity and improve the accuracy of the echo. In long range scales, it

can be ensured that the farthest echoes can be received within a transmitting period

by decreasing the pulse repetition frequency. Once the initial pulse is transmitted and

received, the next pulse will be transmitted. Otherwise, the target detected by the first

transmitted pulse will appear in the next scan and be displayed on the screen. It is

called the second-trace echoes, which will affect radar observation.

As mentioned above, when the range is changed, the pulse repetition frequency also

changes automatically. Some radars are designed with a second-trace echoes

cancellation control which can change the pulse repetition frequency.



.3 Receiver controls (tuning, gain, anti-clutter sea)

(1) Tuning

The tuning control is to adjust the output frequency of the local oscillator, so that the

output of the frequency converter is stable in nominal intermediate frequency. The

radar has a tuning indicator. The tuning control should be adjusted to its maximum

value and the control should then be adjusted carefully until echoes are complete and

clear. If the tuning is not accurate, there will be problems with vague echo edge,

unsaturated brilliance, sparse echoes and poor contrast.

Modern magnetron based radar is usually designed with AFC or AUTO-TUNE control

to keep the best tuning effect. For the purpose of prudence, it is necessary to tune the

radar according to the manufacturer's instructions. A solid state radar usually needs

not manual tuning control. Manual tuning can be used when a problem is suspected

with the auto-tuning.

If the radar screen appears with large areas of clutter or land echoes which are

suspected as SART echoes, the operator can temporarily adjust the tuning control to

the mistune mode. In this mode, the target echo will be weakened or disappear and

the unique echo of SART will be highlighted. After the SART position is determined,

the radar should be tuned immediately to ensure the normal observation. Some

radars are equipped with SART observation control. The same can be achieved by

putting the radar receiver in the detune state and expanding the bandwidth through

using this button. It can highlight SART echoes provided there is no interference from

other echoes.

(2) Gain

The gain control is used to adjust the amplification degree of the intermediate

frequency amplifier and it is also called the receiver sensitivity control. The initial

optimum position of the gain control should make the speckled background noise just

visible. As shown in Fig.2-1.

The gain decreases

gradually

Excessive gain Optimum gain

Fig.2-1 Gain adjustment



If the gain is set too low, the brightness of small or poor target echoes will be weak

and the echo could be easily lost. If the gain is set too high, the strong echoes will

saturate the display and deteriorate echo contrast, which will result in echo details not

being shown. At the same time, the speckled background noise will be enhanced and

the image will become unclear and may be unrecognizable.

When navigating in narrow channels, targets at a short distance can also be detected

by the radiation beyond the horizontal beam width of the radar. Therefore decreasing

the gain at this time can result in higher precision. If there are indirect echoes, multiple

echoes or side-lobe echoes, the radar's gain should be reduced appropriately, so as

to weaken or even eliminate the confusing influence caused by false echoes.

(3) Anti-clutter sea

The radar pulses are reflected in every direction by the waves. A part of the reflected

energy is received by the radar antenna which results in the formation of scaly shiny

spots, which interfere with the radar image. This is called sea clutter. The sea clutter

interference will be stronger at close distance, the closer the distance, the stronger the

sea clutter interference is. The interference caused by medium waves is 3 ~ 6 nm,

while the clutter caused by large waves can reach 8 ~ 10 nm. Interference becomes

rapidly weaker over a longer distance.

Before using the anti-clutter sea, the gain should first be adjusted.

It is recommended to adjust STC according to the actual sea state, as shown in

Fig.2-2. Ensure that weak echoes can be detected as much as possible. It is not

advisable to adjust the STC too high. In general, it is better if some sea clutter

continues to show.



.4 Display controls/menus (display menus and controls, range selector, heading line control, off-centring display, fixed range rings, VRMs, EBLs, cursor, anti-clutter sea, anti-clutter rain, automatic anti-clutter, interference rejection, echo stretch, echo average, target trails)

(1) Display, menu and controls

In the early days, radars applied the plan position indicator (PPI) to show low brilliance.

It only displayed radar echoes with simple measurement tools (such as VRMs and

EBLs). However, modern radars usually use raster display to replace the PPI, as

shown in Fig.2-3. The radar echo display area still adopts the plan position display

mode, which is called the operational display area. The functional areas can be

divided into the operation menu, the target data display area, the operation status

indicator area and the ship information display area and other areas.

Increase STC gradually

The Breakwater echo is clearly visible

Fig.2-2 STC effect

Land echoes

Sea clutter decrease The breakwater

echo is covered by sea

clutter

Long range echo is not

affected by STC

Echoes in short range become weaker

Sea clutter



(2) Range selector

There are many factors that affect

range selection, such as the open

sea, proximity to land and

navigational hazards, weather and

sea state, traffic density, ship's

speed and the observation

frequency of radar. In general, it is

not advisable to start radar

observation from short range scales.

Changing range from long to short

helps to know ship traffic density and observe the shoreline distance and navigational

hazards and determine a safe speed.

Operators should pay attention to the influence of range operation on radar

information. A radar provides more information on a long range scale, while on short

range scale the measurement accuracy is higher and the information is more

intensive. The range selection should always be based on the variable position of the

targets. The minimum range which covers targets is usually selected in order to make

sure that the radar observation has high accuracy.

In poor visibility, frequent range switching should be conducted. A clean radar image

does not mean there are fewer targets. The range should not be changed to long

range scale when there are close dangerous targets.

The change of range scale may also cause change in the display brilliance. It may

neglect small or poor targets in this case. Suspected second-trace echoes can be

identified by a range change. The effective range for collision avoidance is 3, 6 and

12 nm.

(3) Heading line control

Generally the heading line control is a touch reset switch, or a cursor operated switch,

or a spring switch. When pressed, the heading line disappears and reappears when

released. The operator should use the heading line switch frequently, to confirm

whether weak targets are covered by the heading line. This is a routine practice for

the operator.

(4) Off-centring display

When navigating in the open sea, the range between 6 ~ 24 nm is often selected so

as to be well informed of the navigational conditions around the ship at any time.

During offshore navigation, in order to ensure observation accuracy, the range is

Fig.2-3 Display, menu and

controls

Display area

Conning

display

Menu

and

data

display

Operation status

Operation status

Operation status

Operation status



usually between 3 ~ 12 nm. Setting off-centring display not only ensures observation

accuracy, but also increases the observation range in a set direction.

(5) Fixed Range Rings

Fixed range rings provide radar with a reference calibration mark for estimating the

range of target. RRs are much more convenient to measure close moving target.

Normally RRs must be displayed, but the brightness should not be set too high, in

order to avoid the impact on target observation.

(6) Variable Range Markers

VRMs can be used to accurately measure the range of targets. VRM error should be

inspected on each voyage or every month (whichever is less), but generally modern

radars do not need to calibrate VRMs.

Together with VRMs and EBLs, the operator can predict the moving trend of targets

by accurately measuring two continuous positions.

(7) Electronic Bearing Lines

EBLs can be used to measure the bearings of targets. Generally EBL takes the form

of a continuous or dashed line which originates from the own ship's position to the

edge. EBLs can also use off-centring display mode. By fixing the origin to the target,

the bearing between targets can be measured. When proceeding in near-coastal

waters, the operator can use EBLs as the parallel index lines for navigation.

(8) Cursor

Modern computer-based radars have a cursor to display the position with longitude

and latitude where the cursor is located as well as the relative distance and bearing to

the own ship.

The operator can use the cursor to measure the distance and bearing of targets

quickly. However, it is of low accuracy and not suitable for accurate measurement of

the target's location.

For radar collision avoidance function, the cursor can be used to select radar tracked

targets or AIS reported targets.

The cursor controls the radar function via the menu in the screen dialogue area.



(9) Anti-clutter rain

The anti-clutter rain can detect and reserve all the leading edges of echo pulse and

eliminate their trailing edges. In comparison with useful echoes such as ships, islands,

navigational aids, and coastlines, the snow/rain echoes are wider and weaker. After

initiating the anti-clutter rain, it will filter out most of the clutter, leaving only the front

part of the rain/snow clutter area, and the display strength is greatly weakened.

However, other useful echoes are generally narrow and strong. In comparison, there

will be less loss of energy after the removal of the rear edge of echoes, and its

cutting-edge will also be clearer and brighter than the snow/rain clutter frontier.

Therefore, after suppression of rain/snow clutter, the signal to clutter ratio of useful

video signal to rain clutter will be significantly improved. It is worth noting that, after

rain/snow clutter is suppressed, all echoes are subject to varying degrees of

suppression and some weaker echoes may be lost, as shown in Fig.2-4.

In general, when the anti-clutter rain is used, the radar picture displays the following

characteristics:

(a) All echoes are weakened. The target front edge will be highlighted and the rear

edge weakened or dissipated.

(b) The large area of continuous land echoes is split by "differentiation", showing the

frontier of land projection.

(c) It improves the range discrimination of the target.

(d) It may lose small or weak targets.

When anti-clutter rain is used in certain circumstances, the following should be noted:

(a) If the observed target is located in the rain/snow area, with the use of FTC, the

gain should be reduced. This is because the target echoes located among the

rain/snow area are usually stronger than the rain/snow echoes. Such operation can

further reduce the influence of the frontier of rain/snow echoes on the target and

highlight them.



(b) If the observed target is located near the rain/snow area, with the use of FTC, the

gain should be increased. This is because the radar pulse through the rain/snow area

is greatly attenuated. Such operation can compensate for the attenuation on the radar

pulse.

(c) If the observed target is located behind the rain/snow area or far away from it, and

the echo is weaker than the rain/snow interference, the operator does not need to use

the FTC but to increase the gain directly. This is because the target on the screen has

a better separation with rain/snow echoes, and the echoes have been very weak.

Using FTC will further weaken the target echo.

(d) Even when there is no rain or snow, FTC may be used to improve the target range

discrimination.

(e) FTC can also be used to suppress multiple echoes, indirect echoes and side-lobe

echoes.

(10) Automatic anti-clutter

Radar based on modern digital signal processing can suppress sea clutter and

rain/snow clutter better in the automatic anti-clutter mode. In order to ensure the best

ability to detect weak targets close to strong clutter, land echoes or active radar

beacons, it is suggested that automatic anti-clutter be not used or both automatic and

fine manual settings be tried for different types of radar according to the

manufacturer's instructions.

After the use of automatic anti-clutter, there will still be a small amount of clutter

remaining around the radial scan centre especially in rough seas with a higher

antenna.

Fig.2-4 Rain suppression effect



(11) Interference rejection (IR)

Interference rejection is a video processing method which uses radial scan line

correlative detection technology, doing correlation detection for two or more scan lines.

Therefore, unstable weak echoes will be much decreased.

(12) Scan correlation

Scan correlation is based on modern digital signal processing, which performs

correlation detection to multiple consecutive whole scanning images of radar so as to

remove interference and noise more efficiently. But it also removes unstable echoes

of weak targets, fast targets and marginal information of targets. Therefore, it should

be used cautiously while fast and weak targets within close range should be identified.

(13) Echo Average

Echo average is based on scan correlation, which does averaging to two or more

images. The intensity of reliable echoes is unchanged, but not clutter. After averaging,

screen display brightness is reduced, thereby improving the SNR of the screen echo

signal.

It is applied to situations where the density of sea clutter or rain/snow clutter is low. To

some extent, it can improve the ability to detect targets in the clutter. For example, in

ground-stabilized true-motion presentation modes, the ability to detect fixed targets

such as a light buoy in waves can be enhanced by this control. But it is unfit for a

situation where small high speed targets exist. Obviously, the echo average should be

used in the azimuth stabilized display mode. This control should not be used in rough

seas.

(14) Echo Stretch

Echo stretch is a video processing method which amplifies the echo image

information in order to be observed in some types of radar.

There are three ways to conduct echo stretch:

(a) Bearing stretch: Echo laterals stretch when the leading edge and trailing edge of

an echo remain unchanged.

(b) Range stretch: The trailing edge of an echo stretches when the positions of the

leading edge and both sides remain unchanged.

(c) Bearing and range stretch: Echo stretch on the trailing edge and laterals

simultaneously.



Weak target echoes can be extended by echo stretch. However, noises can be

extended at the same time. Therefore, noise should be suppressed before echo

stretch is used.

(15) Target trail

Target trail is the track recorded by screen afterglow over a period of time, as shown

in Fig.2-5.

There are true target trails, relative target trails, sea-stabilized target trails and

ground-stabilized target trails. True target trail can only be obtained with sensor

information of THD and SDME.

Through observation of true target trail, the operator can easily determine the ship's

encounter situations and estimate target ship's speed. Through observation of relative

target trail, the operator can quickly determine whether collision risk exists.

.5 Correct adjustments of controls

Radar start-up operating sequences are generally as follows:

(1) Make sure that the antenna is clear of obstacles; turn on the antenna power switch

and radar power switch.

(2) Preheat for 3 to 4 minutes, and then transmit.

(3) Set brilliance to optimum level and anti-clutter control to zero position.

(4) Check heading and speed inputs are correct.

(5) Select medium or long range scale. Set the presentation of radar display.

(6) Set up the display orientation (headup/northup/course up).

(7) Set mode of display (relative motion/true motion).

(8) Set gain so that the speckled background noise is just visible.

(9) First use manual tuning to maximum level of the tuning indicator, and then switch

to automatic tuning. Tune again 10 minutes later.

Fig.2-5 Target trails



(10) Select the appropriate range scale according to the needs of the navigation

environment.

(11) Adjust A/C sea control to break up the sea clutter into small dots so that small

targets become distinguishable.

(12) Adjust Interference Rejection control if necessary. Choose Interference Rejection

level to reduce interference that has little impact on weak echoes.

(13) Adjust A/C Rain control if necessary to split up unwanted rain echoes into a

speckled pattern, so as to make useful targets distinguishable.

.6 Detection of small or poor echoes

The detection of small targets is the key to safety of navigation. In case of improper

brightness, improper tuning, too low gain, too much suppression of sensitivity-time

control (STC), using fast-time control (FTC) in fine weather, using interference

rejection (IR) without same-frequency interference and using automatic anti-clutter,

scan correlation and echo average in the azimuth unstabilized display mode, the risks

of loss of weak targets, especially the fast weak target within the close range will

increase.

.7 Effects of saturation of receiver noise and/or clutter

Excessive gain will cause strong receiver noise/clutter and amplifier saturation, which

can neither enhance the target's intensity nor increase SNR. Hence the strong targets

will be hidden in the noise. Besides, the excessive gain will also cause target blurring

and deteriorate range and bearing discriminations and accuracies.

.8 Importance of frequent changes of range scale

A frequent change of range scale is important to:

(1) balance far and close targets, and be aware of the surrounding traffic density, the

positions of obstacle, danger, navigation target and coastline with respect to the own

ship.

(2) obtain a large amount of information at long ranges; obtain high precision of

information at short ranges.

(3) obtain the overall traffic awareness at long ranges, avoid collision at short ranges.

(4) recognize second-trace echoes.

.9 Different types of presentation modes

For the officer in charge of a navigational watch, the selection of presentation modes

is the crux of the matter to obtain proper safety information. The instructor should

attach special importance to this part. A presentation mode depends on the setting of

the ship's motion mode (including the reference point and the reference speed) and

the screen orientation mode. The relative motion mode is the common setting in

collision avoidance situation, particularly, in a situation where an ARPA or TT/AIS



function could not provide reliable information in time. Note that the true motion mode

in radar operation is highlighted in resolution MSC.192(79), Performance Standards.

With satisfactory information integrity and accuracy from sensors, and with availability

of time to acquire collision information through the ARPA or TT, the true motion

presentation mode presents more realistic scenario.

(1) Relative-Motion presentation modes

In relative-motion presentation modes (defined as "equivalent to true motion with a

fixed origin" in resolution MSC.192(79), Performance Standards), CCRP (and the

radial scan centre), which always represents the effective position of the observing

ship, is stationary. In consequence, targets exhibit their motion relative to the

observing ship. The targets' motion equals to the sum of their true velocity vector and

the own ship's true velocity vector. In particular, in the absence of any leeway, the

movement of fixed targets at sea is reverse and isokinetic with the own ship, and the

movement of target's ship with the same velocity vector of the own ship is stationary.

If CCRP coincides with the geometric centre of the operational display area, it is

called centre display mode. Otherwise, it is called off-centred display mode. On

selection of off-centred display, there are more display areas ahead so that targets

can be observed expediently.

(a) Relative motion Head-Up display

Relative motion head-up presentation is often described as an unstabilized mode.

Radar can work properly without other sensors' information in this mode. The

characteristics are as follows:

I. The characteristics of relative-motion presentation are as described above.

II. Heading line connecting CCRP at the top of the display (000) indicates the own

ship's heading. The displayed radar picture corresponds directly with the scene

viewed through the wheelhouse window in this mode only. The relative bearing of the

targets can be obtained in this way.

III. Yawing movements of the ship will cause echo swing. The afterglow trail of targets

and accumulation of echoes will lead to a false appearance that the bearing of a target

is changing, while in fact the true bearing remains constant. If the ship's course is

altering while the heading line remains constant, the picture will rotate in a reverse

direction. This will affect observation, especially when the own ship is altering heading

rapidly and significantly and the target's echoes become blurred.

IV. Intuitional observation can be obtained; it is applied to collision avoidance in a

calm open sea.



V. Unfavourable to position-fixing, navigation and environment in which course is

changed frequently, such as a ship entering into port, narrow waterways and mostly

coastal waters.

VI. Target trails, anti-clutter control and target tracking (TT), etc. which can work

properly only in stabilized display mode, will be restricted.

For a radar in normal working condition, the head-up orientation mode is not a regular

function in accordance with resolution MSC.192(79), Performance Standards. When

the heading sensor is not functional, this mode will be used as a backup and fallback

mode with an alarm indication.

It is worth noting that some types of radars are provided with stabilized head-up mode.

Radar echoes are shown in the same way as in the head-up mode. The difference

from normal unstabilized head-up presentation lies in the orientation of the bearing

scale. The bearing scale is stabilized by the heading sensor. This adapted H-up

presentation is known as stabilized H-up presentation or H-up TB (True Bearing)

presentation.

Visual illustrations help to have a direct and clear understanding of characteristics of

radar pictures in various display modes. The chart scenarios are illustrated in Fig.2-6.

Fig 2-7 shows the characteristics of RM H-up presentation.



(b) Relative-Motion north-up display

This is stabilized bearing display mode that requires access to information of the own

ship's heading. Display characteristics are as shown in the Fig.2-8:

Fig.2-8 RM N-up presentation

Altering Before alteration

000

180

CCRP

180

000

CCRP

Before alteration Altering

Fig.2-6 Scenarios on chart

215

(b) Altering (a) Before

alteration

270

180

000

090

Fig.2-7 RM H-up presentation

000

090 270

180

CCRP

CCRP




II. The top of the screen represents true north; the heading line is from CCRP to the

own ship's true heading. The displayed radar picture corresponds directly with the

paper chart in use. True bearing of targets can be obtained directly by bearing

measurement.

III. When the ship is yawing in bad weather and rough seas or the own ship is altering

course, the heading line changes with the ship's heading. The echoes are maintained

stable and clear to facilitate observation.

IV. It is applied to position-fixing, navigation and environment in which course is

changed frequently, such as a ship entering into port, narrow waterways and coastal

waters.

V. When it is used in collision avoidance, especially heading in 090 to 270, the

operator should be aware that the radar picture is contrary to the observation from the

bridge windows.

(c) Relative-Motion course-up display

This is also stabilized bearing display mode which requires access to the information

of the own ship's heading. Display characteristics are as shown in the Fig.2-9:


II. The heading line, which represents the own ship's course from CCRP to the own

ship's true heading, points to the top of screen. The bearing scale on the screen is

driven by the heading and 000 represents true north. The displayed radar image is

(a) Before alteration (b) Altering

180 180

(c) New C-up

215

Fig.2-9 RM C-up presentation



similar to the visual observation by the operator through the bridge. True bearing of

targets can be obtained by bearing measurement.

III. When the ship is yawing in bad weather and rough seas or the own ship is altering

course, this mode has the characteristics of north-up orientation. The heading line

changes with the ship's heading. The echoes are stable and clear to facilitate

observation.

IV. After the course is altered and the own ship's course is steady, press "course-up"

control, and radar picture will be rotated rapidly and restored to new course-up state. It

avoids the problem of fuzzy target trailing in head-up display mode when the ship is

altering course.

V. For both navigation and collision avoidance, course-up mode is suitable for open

waters. But in most situations, the true north is inconsistent with the paper chart,

which is not conducive to target identification and position-fixing.

(2) True-Motion display

These display modes require the own ship's heading and speed to be transmitted to

the radar.

In true-motion presentation modes, the CCRP (and the radial scan centre) represents

the own ship's position, and is going ahead with the own ship's course and speed on

the screen.

If the operator uses speed through water (STW), the drifting ship is stationary and the

land will move with speed and reverse direction of current. Water true-motion mode is

applied to collision avoidance. STW can be obtained by the ship's log in water tracking

mode. The speed can also be input manually so that the radar can work in water

true-motion presentation.

If the operator uses speed over ground (SOG), islands and other fixed objects are

stationary and the own ship and target ships move in accordance with its track on the

screen. Heading does not indicate the direction of movement of ships on the waters

with current. Ground true-motion mode is applied to narrow waterways and navigation

of the ship entering and leaving port. There are many ways to achieve SOG, such as

doing correction of set and drift on STW mode, using ship's log in seabed tracking

mode, using electronic position-fixing system (EPFS, such as GPS). SOG can also be

obtained by radar ground referencing function. It can check the accuracy of SOG by

observing whether a fixed target drifts or not.

According to the provision of radar performance standards, the radial scan centre

shall be at any point at least 50% and not exceeding 75% of the radius from the centre

of the operational display area. The radial scan centre can be retuned manually any

time for better observation.

On true-motion presentations, the radar can provide the three orientation modes as

described above. Since TM head-up presentation does not indicate true movement,

this mode is not available on modern radars. If the own ship's heading information is



lost, the radar will give an alarm and carry out the unstabilized head-up orientation

mode. If the own ship's speed information is lost, radar will also give an alarm and

carry out off-centre relative-motion presentation. If the own ship's speed is set to zero,

the radar will also carry out off-centre relative-motion presentation (defined as "true

motion with a fixed origin" in resolution MSC.192(79), Performance Standards).

.10 Advantages and limitations of presentation modes

Different types of display modes satisfy the different applications of radar. In the

relative-motion mode, continuous observation of echoes is useful for determining the

risks of collision and makes an early decision to avoid collision. Because radar

function is restricted in the unstabilized head-up orientation mode, the operator should

avoid using this mode when the radar system works properly. In coastal waters, when

radar position-fixing and navigation is conducted with paper charts for target

identification, it is better to use north-up orientation mode. When proceeding along the

coast, on the narrow waterways or on entering/leaving port, with the ship yawing and

altering course frequently, it is better to use course-up orientation mode which is

suitable for collision avoidance.

When conducting collision avoidance in water true-motion mode, the operator can

easily and accurately determine the target ship's dynamic movement and make

avoidance decisions according to encounter situations and the International

Regulations for Preventing Collisions at Sea (COLREGs). In true-motion mode, the

motion of the target ship is unrelated with the own ship's manoeuvring, which benefits

monitoring the movement of the target ship during and after avoidance of the ship. In

the ground true-motion presentations, the operator can monitor the ship's dynamic

movement with respect to coastal and fixed obstructions. This mode is the best choice

when the ship navigates in narrow waterways and in port. It is worth noting that the

operator must strictly distinguish the water stabilized mode and the ground stabilized

mode. It is recommended to use the sea-stabilized mode for collision avoidance and

the ground stabilized mode duing navigation in the confined waters.

.11 The need for heading and speed inputs for relative stabilized and true motion display

(1) Azimuth-stabilized display

Azimuth-stabilized is a presentation mode in which heading reference input is used to

orientate the heading line on the radar display. In the absence of stabilization, the

image would rotate by an amount equal and opposite to any change in observing

ship's heading. The heading stabilization signal is used to simultaneously produce a

commensurate rotation of the image in the same direction with the change of heading.

As a result, it eliminates the angular wander of the image due to yaw. Not only does

this eliminate the masking of targets by the afterglow generated during an alteration of



course, but it allows true bearings to be read off directly and quickly from the fixed

bearing scale.

(2) True-motion display

In a correctly adjusted true-motion presentation mode, it is essential to input course

and speed information from THD and SDME. The echo movement of the own ship

and all targets are rendered independent of the observing ship's motion. This is

achieved by making the origin of the image to track across the screen in a direction

and at a rate which corresponds with the motion of the observing ship. True-motion

mode can be divided into true-motion mode relative to water and true-motion mode

relative to ground. See above for details.

.12 Effects of transmitting heading error on stabilized and true motion display

If azimuth-stabilized (North-up or Course-up) is selected, the displayed heading

should be correctly aligned to the ship's true heading. Otherwise, errors in true

bearings will be produced. A check should then be made to ensure that the

transmitting heading follows the ship's heading.

.13 Effects of SDME error on true motion display

When speed error exists, all the displayed tracks will be in error and that misleads the

observer.

An error in the own ship's log will produce non-zero speed indications on all stationary

targets being tracked. It may also produce large errors in the aspects of very slow

moving targets.

.14 Specific controls/menus (presentation modes, speed controls, reset controls, heading information)

(1) Presentation modes

The radar has different image display modes in order to meet the requirements in

different navigation environments. On operation control/menu, the radar has ship's

motion presentation and orientation control. Motion presentations contain

relative-motion and true-motion selector. Orientation modes contain head-up, north-up

and course-up.

(2) Speed controls

The speed of the ship can be referred to sea and ground.

Speed through water can be used in ocean and collision avoidance. The sensor

provided with STW is the ship's speed log in water tracking mode. The speed can also

be input manually, but large error may exist.



Speed over ground can be used in coastal navigation. The sensors provided with

SOG include sea bottom tracking speed-log, GNSS equipment and radar. Also, the

speed can be input manually, but large error exists.

(3) Reset controls

There are two reset operations. In the case of course-up display mode, course-up

reset is used to set new course. In the case of true-motion presentations, the reset for

selected antenna position is used to set the own ship position on the display.

(4) Heading information

Heading information is provided by THD. According to SOLAS Convention, for ships

of 500 gross tonnages or more, the heading is usually provided by the gyro-compass,

and for ships of 300 to 500 gross tonnage by the magnetic compass. For the simulator,

when the compass repeater degree is incorrect, it should be calibrated in accordance

with the instructions. According to resolution MSC.192(79), Performance Standards,

electronic means should be provided to align the heading line to within 0.1. However,

the previous radar standards require that the errors of heading line must be less

than 1°.

.15 Incorrect setting of controls and their effects and dangers

Incorrect setting of the controls may seriously affect radar observation. The operator

should pay attention to adjusting radar anytime, anywhere and according to the needs

of observation, so as to keep the radar in the best display mode.

(1) Screen brightness and contrast disorder: The screen is too bright with excessive

contrast; the image is not suitable for visual observation. Furthermore, it is hard to

observe and distinguish image details.

(2) Gain is too high so that the echo loses focus, which will result in low resolution and

measurement accuracy; gain is too low, which will result in loss of small targets. New

operators will often see an illusion by using raster display radar, thus inadequate gain

will be used often.

(3) Most radars have automatic tuning, but for every radar transmitting and bridge shift,

it is very important to compare automatic tuning with manual tuning to confirm the

reliability of automatic tuning.

(4) Inappropriate range selection, or lack of long range scanning may ruslt in

important information from being displayed on the radar screen.

(5) Incorrect setting of A/C sea can cause the echoes of close targets submerged by

sea (insufficient suppression) or lost (excessive suppression). Incorrect setting of A/C

rain may hide the echoes of targets nearby or in a snow area or lose small targets

within the range. Using IR in the absence of the same frequency interference or overly

using IR will cause loss of weak echoes. In a complicated environment with all kinds



of clutter, using a variety of clutter suppression devices and trying to display a

clutter-free image may cause greater negative effects.

(6) The functions involved in digital signal processing methods, such as echo stretch,

scan correlation and echo average, should only be used when needed. Doing this

may severely reduce screen resolution and damage useful information, in particular

small target information.

(7) Target trail display

Whether it is true trail or relative trail, they all leave an afterglow of the own ship or

targets on the screen. The afterglow is helpful to radar application, but the trail of a

long stay on the screen will cause interference. Therefore, Incorrect setting can be

avoided by cleaning the trail in the appropriate time.

.16 Detection and correction of incorrect settings

It is essential to check and correct the Incorrect setting of the control in order to

ensure radar application. It requires the operator to have long-term practice and

gather experience. The aim of radar control/menu is to ensure obtaining more

comprehensive information at any given time of observation. Thus, in radar

observation, every operator is required to make comprehensive adjustments to the

radar control to obtain the best effect for each target echo. Any operation of radar

control/menu for a specific image may cause Incorrect setting for other observations.

Incorrect settings should be recognized and adjusted instantly. The control should be

correctly adjusted to ensure radar lookout, observation, navigation and collision

avoidance for the best effect of radar application.

The sequence of checking control/menu is usually as follows: brightness and contrast,

sensor setting, display, tuning status, gain level, pulse length, level of clutter

suppression.

.17 Effects of incorrect speed setting and CMG correction on true motion presentation modes

Correct course and speed input must be fed in when the True Motion display is used.

Errors of speed and heading can lead to target true data error, and result in wrong

situation assessment.

The operator can determine whether the input errors of speed and heading exist by

observing stationary targets.

.18 Purposes and use of performance monitor

The performance monitor should be available (automatically or by manual operation)

while the equipment is operational, to determine a significant drop in system

performance relative to a calibrated standard established at the time of installation.



The sensitive element which makes monitoring possible is usually a unit known as an

echo box or a transponder.

A performance check should be carried out as soon as practicable after setting up and

thereafter at regular intervals.

The important basic rule for carrying out a performance check is to consult the

manufacturer's manual and follow exactly the instructions given therein.

.19 Record of radar data (radar logbook, radar maintenance records, radar hand-over records)

(1) Radar logbook

The radar logbook can be available to assist the operator to record daily use. The

form of radar logbook may vary with different ship owners. The operator needs to

record radar on-off time, weather, sea condition, the ship's position and specific

conditions when using it.

(2) Radar maintenance records

Maintenance records should record the contents of scheduled and unscheduled

maintenance work, including time, place, the name and number of consumables

(should be consistent with the record of inventory) and signature, etc.

Repair records should describe in detail the time and place of radar failure, symptoms,

repairing time and place and a brief repairing process, the name and number of

replacement parts, service provider and their contact information, inspection results

and signature of acceptance after repairing.

(3) Radar hand-over records

Radar hand-over is part of ship hand-over work. It includes the relevant materials of

radar equipment and hand-over records of current radar working condition. The

records should be co-signed by the shift officers and then archived.

The changing history of performance monitoring data and the revision history of

measurement accuracy (range and bearing) should be recorded continuously at work.

The diagram of radar shadow sectors and short-distance blind area should be posted

on the bridge, recorded in the radar logbook, and be kept valid.

.20 Target detection affected by propagation conditions

When electromagnetic waves are crossing rain, snow, hail and fog zones, they not

only cause clutter, but also lead to energy loss that decreases the detecting ability of

the radar.

When sub-refraction occurs, the radar beam is bent downwards slightly less than

under standard conditions. The detection range will be reduced and low altitude

targets may disappear from the display.



When super-refraction occurs, the radar beam tends to bend down slightly more so

that targets may be detected at ranges which are slightly greater than standard. This

can result in the detection of unwanted "second-trace" echoes, which can be identified

by changing range scale frequently.

.21 Effects of incorrect CCRP setting

The consistent common reference point (CCRP) is a location on the own ship, to

which all horizontal measurements, such as range, bearing, relative course, relative

speed, CPA or TCPA are referred, typically the conning position on the bridge. Where

multiple antennas are installed, there should be correct offsets for applying different

CCRP positions for each antenna in the radar system. Otherwise, there will be

measurement errors to the CCRP on the display.

The setting of CCRP offset should be implemented when installed. The

synchronization error should be calibrated first, and then CCRP position is set and

adjusted according to the manufacturer's documentation.

Demonstration and practical training

2-1 Radar setting up and adjustment


.1 Methods and accuracies of range measurement (RRs, VRMs, cursor)

The operator can use fixed range rings, VRMs and cursor to measure the range of the

target as shown in Fig.2-10.

(1) Rings

Fixed range rings provide the radar with a reference calibration mark for estimating

ranges. According to resolution MSC.192(79), Performance Standards, the accuracy

of RRs should be 30 m or 1% of current range (whichever is greater).

(a) RRs (b) VRM (c) Cursor

Fig.2-10 Three different methods of measuring the ranges



Fixed range rings can be used to estimate the ranges when the target distance needs

to be estimated quickly under the large ranges (error is less than 5%).

(2) VRMs

VRMs can be used to measure the ranges. According to resolution MSC.192(79),

Performance Standards, at least 2 VRMs are required and should have a digital

display window for activated VRMs. The error of VRMs should be within 30 m or 1% of

the range scale in use, whichever is greater.

Before the use of VRMs for PPI radar, it should be calibrated with RRs. This work can

be done at any time, or at least each voyage or every month (whichever is less). But

modern radars do not need calibration of the VRMs.

(3) Cursor

The cursor can be used to measure the ranges quickly, according to resolution

MSC.192(79), Performance Standards. The accuracy of range measurement

provided by the cursor should comply with the relevant requirements of VRMs.

.2 Accurate range measurements

(1) The preparation before range measurement

(a) Adjust the radar picture to make the echo display clear.

(b) Select a proper range when the target is located in the 50~90% position of the

display area.

(c) Select the front edge of the specific target.

(d) When measuring range for position-fixing, appropriate targets which are clear,

sharp, and isolated should be selected. When measuring ranges for multi-targets,

measure them at abeam direction first, then fore and aft.

(2) Accurate range measurement

The VRM can be used for accurate measurement of a target distance. Different

methods are available to measure the ranges for the long and short distance targets

respectively.

(a) If the target is within the radar horizon and the front edge is able to be detected,

the echo of the front edge can be used to measure the target distance. Efforts should

be made to keep the internal tangent between VRM and the target's echo so as to

eliminate the error resulting from the influence of the size of pixels of the monitor.

(b) If the target is outside the radar horizon and the front edge cannot be detected, the

echo of the rear edge is used to measure the target distance. The transmitter should

be changed to shorter pulse, and the Gain of echoes should be decreased properly.

Efforts should be made to keep the external tangent between VRM and the rear edge

of the target's echo so as to eliminate the error resulting from the influence of the size

of pixels of the monitor.



.3 Methods and accuracies of bearing measurement (EBLs, cursor)

According to resolution MSC.192(79), Performance Standards:

(a) A bearing scale around the periphery of the operational display area should be

provided. The bearing scale should indicate the bearing as seen from the CCRP.

(b) Electronic means should be provided to align the heading line to within 0.1.

(c) At least two electronic lines (EBLs) should be provided to measure the true or

relative bearing of any point object within the operational display area, with a

maximum system error of 1 at the periphery of the display. Each active EBL should

have a numerical readout.

(d) It should be possible to move the EBL origin from the CCRP to any point within the

operational display area and reset the EBL to the CCRP.

(e) The cursor can be used to quickly measure the ranges, but the cursor only

measures the ranges coarsely due to its large tolerance. Therefore, it is not an

accurate tool to measure the position of the targets.

N.B. According to the IMO performance standard for radars, the errors of measuring

bearings must be less than ±1°; the errors of the vessel heading line must be less

than ±1°; the input errors of the ship's heading must be less than ±0.5°. For details

please refer to Appendix I-5.

.4 Accurate bearing measurements

(1) Preparation

(a) Adjust the radar picture to make the echo display clear.

(b) Select a proper range so that the target is located in the 50~90% position of the

display area.

(c) When measuring bearings for position-fixing, appropriate targets which are clear,

sharp, and isolated should be selected. To measure bearings for multi-targets, the

operator should first measure them at the fore and aft direction, then at abeam.

(d) For measurement of bearings for specific targets, refer to the following methods.

(2) Accurate bearing measurement

EBLs should be used to measure the target bearing accurately; different methods are

applied to measure the bearings for different shapes and distances respectively.

For a point target, the centre of the echo is selected as the measuring position;

otherwise, a proper measuring position in terms of the different targets needs to be

selected. If the target is within the radar horizon, the front edge is able to be detected;

the echo of the front edge can be used to measure the target bearing. When

measuring the target bearing, the gain of the echoes should be decreased properly,

and the EBL should be a tangent externally with the echoes. This operation is helpful

to eliminate the error resulting from the influence of the size of pixels of the monitor.



When reading the bearings, the width of horizontal beam of the antenna should be

considered, if the left of an echo is measured, the half-beam width should be added to

the bearing. On the contrary, if the right of the echo is measured, the bearing should

be subtracted with the half-beam width. If the target is outside the radar horizon, the

front edge cannot be detected; the centre of the echoes is selected as the measuring

position.

.5 Errors in range and bearing measurements and corrections

(1) Range errors

Select the minimum range to observe whether the

shape of the linear target is curved or not. This adjusts

and eliminates the time synchronization error if there is

a range error.

Adjust the synchronous device of the trigger pulse in the

display or set the delay time of the trigger pulse in the

maintenance menu so as to ensure the shape of the

linear target in short range recovers the linear shape, as

shown in Fig.2-11.

(2) Bearing errors

(a) Heading line errors

In fine weather, when the ship docks, ensure the stability of the ship heading, choose

H-up orientation mode and use 6 nm range scale, select a point target from 3 nm, use

EBLs measuring the bearing, compare with Gyro; if the difference between the two

values is greater than ±1°, there is a bearing error. Then adjust the error less than ±1°

by referring to manufacturer's instructions.

(b) Compass repeater errors

Compass repeater error will cause the fixed error of the heading line and the true

bearing. The error can be eliminated through comparing radar compass repeater with

the master compass, and then adjust the reading in accordance with the master

compass. Generally compass repeater error can be inspected at any time, or at least

each voyage or every month (whichever is less).

.6 Bearing and range measurements with offset EBLs and VRMs

As shown in Fig.2-12, set the cursor to the centre of target 1, then activate the EBLs

and VRMs. Move the origin of EBL to the position of cursor by EBL OFFSET. Then

make the EBL cross target 2. The bearing from target 1 to target 2 can be measured,

and the range between target 1 and target 2 can be measured by VRMs.

A

B

Fig.2-11 The adjustment of

radar range error




2-1 Radar setting up and adjustment


Through the instructor's demonstrations and trainees' practice, the following

capabilities should be achieved:

(a) To be familiar with the display interface of the radar, control names and functions,

use turn on/off and adjust radar echo video image.

(b) Use different types of presentations.

(c) Correctly identify radar picture, targets, clutter and false echoes.

(d) Understand the impact of Incorrect setting of control on radar picture.

(2) Training mode

Practice with a live radar, including radar simulator.


(a) Preliminary procedures: Check whether the antenna is clear, check the switches

and controls.

(b) Operation: turning on the radar, verifying sensor's data and adjusting to optimum

condition.

I. Switching on

Turn on the ship's power supply

Turn on power of radar

Explain why radars need preheating before transmitting for a magnetron radar

Turn on transmit switch

Fig.2-12 The range and bearing measurements between two targets by the off-centre of ERBL



II. Adjusting

Adjust brightness, gain and tuning; make the radar picture to optimum condition.

Select range scale

Select orientation mode (head-up/north-up/course-up) and motion mode (relative

mode/true mode)

III. Verifying other sensors data

Verify the own ship's heading, ship's speed, AIS data and GPS data

IV. Operation of observing targets according to the sea condition and navigation

environment

In case of favourable echo conditions, the operation process of A/C sea control, A/C

rain control and interference rejection should be demonstrated. Otherwise, this

process should be described orally. In addition, the identification process of indirect

echoes, side-lobe echoes, multiple echoes, and second-trace echoes should be

demonstrated. Otherwise, this process should be described orally.

V. Turning off the radar

Turn off transmit, switch to standby mode

Rotate brightness counter clockwise to minimum (for PPI display)

Turn off radar power switch

Turn off the ship's power for the radar


Assessment upon completion of the topic can be conducted in forms of written

examination, oral test, practical demonstration, exercise scenarios, discussions and

class records, etc. in order to assess whether a trainee satisfies the required

performance. Focusing on radar operation skills in this topic, the trainee should:

(1) acquire the primary knowledge on the operation and controls of the radar;

(2) setting up the radar in accordance with the manufacture's instruction;

(3) demonstrate operational use of the radar including the limitation of the equipment;

(4) operate the radar on different modes and displays; and

(5) measure targets by range and bearing accurately.

Teaching guidance

Radar operation is the core teaching content of this course, which provides the basic

knowledge and skills for lookout, observation, position-fixing, navigation and collision



avoidance. In the teaching process, it is advised that the instructor should explain and

demonstrate with typical cases at sea, radar echo pictures, and radar videos, in order

to obtain the best effect. The demonstration and practical training is vital in this topic. It

is advised that the instructors supervise the trainees' operation on the basis of prior

demonstrations. During the whole process, instructors should have sufficient

interaction and individualized communication with trainees with various characteristics,

so that they are able to operate radar with confidence. Trainee operating time should

be no less than two-thirds of the whole training time.

Insufficient understanding of essential points in radar operation may occur during the

teaching process. The instructor should highlight the particularity and complexity of

radar operation. On the one hand, radar operation is different from other stand-alone

information source devices (such as gyrocompass, speed log, GPS, AIS). The radar

system is the processor of integrated information from these sensors. The officer in

charge of a navigational watch needs not only to acquire the information from radar,

but also to set up the sensors correctly, so that the radar can output the optimal

outcomes based on the information. On the other hand, the control of radar

information processor is far from intelligent and convenient. To ensure safe navigation

by using the multi-sensor integrated terminal, the radar operation for lookout,

observation, position-fixing and collision avoidance could be extremely complicated,

especially when facing changing weather or sea conditions and a variety of target

environments. Under such circumstances, users have to grasp the basic knowledge

of radar, develop an understanding of the principles of radar and acquire proficiency in

basic function operations.

Due to the different ships equipped with different types of radar equipment, the

applicable standards are also different. Appropriate teaching plans meeting specific

requirements should be developed in different contexts. For example, for the PPI

display radar equipment, echo stretch, echo average and CCRP, which are covered in

modern radars, may not necessarily be involved; however, the mechanical cursor and

focus operation should be added. For training institutions in compliance with

resolution MSC.192(79), Performance Standards, the separate antenna power switch

may not be involved. For radar systems based on integrated information processing, it

should be emphasized that the integrity information is the key to ensuring its proper

operation, and that the azimuth-stabilized data from THD is indispensable information

for a modern digital video processing radar. In case of a lack of azimuth-stabilized

information, for example, a wrong choice of unstabilized H-up presentation mode,

radar normal functions may be severely affected, resulting in serious defects in radar

information. It is worth noting that the effect of scan correlation, echo average and

echo stretch are largely determined by the hardware and software of the radar.

Therefore, for different generations and different types of radar, the presentation

results by the same function might vary greatly. Past experience in operations cannot

be applied to other types of radar directly.



The instructor should also attach the importance to radar operating skills in

accordance with navigation practice. For example: STC is not only used to suppress

sea clutter, but also can be used to suppress and eliminate indirect and side-lobe

echoes. Even when the area covered by the tropical rainstorm is within 10 nm of the

own ship, it can be used to suppress rain clutter while observing distant targets

beyond that area. Tuning can be used to obtain a fine radar image. However, in

search and rescue operations, it is also used to observe clear SART echoes in

de-tuned state. With the development of radar technology, auto-tuning has been

widely adopted, but it is still very important to emphasize the difference between

manual tuning and auto-tuning images.

Skilful use of the VRMs and EBLs to measure the range and bearing of a target in a

fast and accurate manner is the basic skill for radar position-fixing and navigation. It

should be noted that the accuracy of range measurement is high, but bearing

measurement is low. Because of the influence of the radiation energy which is outside

of the horizontal beam width, the accuracy of bearing measurement within 1.5 nm

would decrease rapidly.

For teaching plan design, it is recommended that the instructor demonstrate how to

measure ranges and bearings with simulation scenarios. The instructor should first

demonstrate the procedures and skills of range measurement by RRs, VRMs and

cursor; then the procedures and skills of bearing measurement by EBLs and offset

EBLs; and finally explain the influence of measurement accuracy on position-fixing

and navigation.

In consideration of the importance of radar operation, a scheme for practical training is

included in this topic. The use of the radar simulator may not achieve satisfactory

teaching effectiveness due to the status quo of radar technology. It is recommended

that practical training be conducted on a live radar, so that real experience of radar

operation can be obtained and false preconceived experience owing to simulation

deviation be avoided. In practical training, on the basis of optimising the brightness,

gain and tuning, and focus, the trainee should be trained to be able to always keep

optimum visual effects at different times in various environments and for different

targets.

The importance of safety can never be ignored in the course of teaching. The

instructor should keep stressing the importance of personal safety, equipment safety

and navigation safety in radar use. The importance of safety checks before starting

the radar, compliance with safety operation procedures and maintaining the best

working conditions of the radar to ensure safety of navigation should be kept in mind

during the whole course of instruction.



3 Using radar to ensure safe navigation


This topic mainly includes radar position-fixing, radar navigational aids and radar

navigation.

Understanding the content of this topic is the key to using radar parallel index lines

(PI), maps, navigation lines, routes and electronic chart navigation correctly, so as to

ensure the safety of navigation.


The operator should select the proper target that is suitable for radar position-fixing

based on navigational charts. The operator should take account of the distribution and

characteristics of targets, range measurement and bearing measurement, and the

requirements of position-fixing and navigation.

.1 Characteristics of good, conspicuous radar targets

The basic principles for selecting targets are as follows:

(1) Select the target echoes that are stable, clear, highly accurate and exactly

matching with nautical charts.

(2) Select the targets that are near, less distorted and easily identified on nautical

charts.

(3) Select multi-targets for position-fixing when the angles of two or more position

lines meet the requirement of navigation position-fixing. The operator can also use

range or bearing to a single target for position-fixing when the target is considered

very reliable.

The echoes of good targets are stable, clear, highly accurate for measurement and

exactly matching with nautical charts, which are preferred targets for position-fixing,

such as an isolated island, island-reef, cape, jetty and isolated lighthouses with

obvious signs.

If the instructor describes the above contents with nautical charts in the teaching

process, it is helpful for trainees to get a quick grasp of the basic knowledge.

.2 Characteristics of poor radar targets

The positions and shapes of poor radar target echoes are not stable; they change with

the tide. Some echoes are weak and others are blurry. These kinds of targets should

be avoided in position-fixing. For example, echoes depicting the position and shape of

a gentle beach shoreline echoes will change with tide, and are not stable. The echoes

of a gentle slope are weak and those of buoys are blurry.



.3 Radar position-fixing methods

Radar position-fixing means that the operator

draws the range and/or bearing lines to obtain

the ship's position by comparing target

characteristics on the chart with radar echoes,

selecting suitable targets and using radar to

measure the range and/or bearing of the target.

Instructors can refer to Fig.3-1 to explain this

part.

(1) Observe the radar range and/or bearing of

the target.

(2) Identify the targets used for fixing on the

chart.

(3) Draw the range and/or bearing line from the

target as observed.

(4) The intersection of the position lines or centre of the geometrical figure formed by

the position lines is the ship's position.

The operator can use the range line and bearing line obtained from radar observation

for position-fixing. Radar fixing can be done by one of the following four methods:

(1) Position-fixing by the range and bearing lines of a single target

This method is based on the range and bearing lines of a single target intersecting at

one point, which is the observed position. The fixing accuracy of targets must be

considered when selecting the targets and the nearer, isolated target with a strong

and stable echo should be selected. This method is the only reliable position-fixing

method when only one isolated target can be used for position-fixing. The wrong

target identification will result in serious consequences if there are confusing

multi-targets. An obvious advantage of position-fixing by the range and bearing lines

of a single target is that it can be completed in a short time and the angle intersected

by the two lines is 90°.

(2) Position-fixing by the range lines of two or three targets

As shown in Fig.3-2, the ship's position which is near the

DR (Dead Reckoning) position, can be determined by

two range lines obtained by observing the ranges of two

targets simultaneously. The ship's position is at the

centroid of the triangle obtained from observations of the

ranges of three targets simultaneously.

Fig.3-1 Radar fixing

Fig.3-2 Two targets range fix



In many situations, more than three range lines can be used for position-fixing. A time

lag between the observations results in a decrease in position-fixing accuracy. A

target with a fast changing range should be observed later. The accuracy of radar

position-fixing also depends on the angles of the position lines. Range line fixing

should be done with care. In general, the echo of a ship abeam should be observed

first and the time lag between observations should be reduced as much as possible.

(3) Position-fixing by two or three bearing lines of targets

Satisfactory position-fixing accuracy can be obtained when small, isolated, stable and

conspicuous radar targets' centre bearing is observed. The advantage of this method

is that it can be done in a short time and the ship's position can be determined roughly

by the bearing lines before accurate fixing.

(4) Mixed fixing by range lines and bearing lines of multi-targets

The proper angle of position lines can be obtained from two or more isolated and

conspicuous radar targets, and the method of combining range and bearing

measurements can be used for position-fixing. The interaction of range lines from two

identified targets and one bearing line from another target can be used to determine

the ship's position. The accuracy is high. Similarly, the combination of bearing lines

from two reliable targets and one range line from another target can be also used to

obtain an accurate ship position.

.4 Position-fixing errors and methods to improve fixing accuracy

Factors that cause radar position-fixing errors are as follows:

(1) Position-fixing is usually carried out when the ship is underway and fixing results

are behind the ship's actual position.

(2) Errors exist in the radar observation resulting in errors in position-fixing.

(3) Errors arise from inappropriate position-fixing methods.

Ways to improve accuracy of position-fixing are as follows:

The operator should be familiar with radar operation, and maintain optimal radar

images. Fixing should be done quickly and multi-targets should be selected as

appropriate. If the condition admits, try to choose multi-targets for position-fixing.

Regarding the operational methods to improve accuracy of position-fixing, please

refer to A1 2.2.

.5 Cross check of reliability of radar position-fixing with other navigational aids

Errors exist in radar fixing. Wrong position will be obtained from wrong target

identification. A radar fix should be compared with satellite positioning, landmark fixing

so as to improve the accuracy of the radar fix.



.6 Comparison of coast features on chart with that on radar picture

A land echo is basically an integral whole. Echo strength is related to the land feature,

height, slope gradient, slope structure, slope cover, etc. but has little to do with the

extent of the land.

When the ship approaches the mainland from the ocean, the high hills of the distant

land are first detected by radar and their echoes are much smaller than the actual land

area. Generally, the echo of a distant target has greater distortion and is difficult to be

identified. When the ship approaches the mainland and the targets are within the

radar horizon, although the shoreline frontiers can be detected, the feature of the

shoreline does not completely match with the chart. This causes difficulty in target

identification (see Fig.3-3).

Most echoes of islands match well with charts.

The echoes of near islands forefronts are more

accurate, which are the ideal reference positions

for radar range measurement. It should be noted

that it is difficult to separate echoes of the

mainland from that of the islands adjacent to it if

they are observed from a distance.

Port navigational aids include lighthouses, light

vessels, buoys and radar beacons. Isolated

lighthouses and light vessels are good radar

targets, but the echo of a buoy is weak. Special

attention should be given to the echoes of buoys

that are glinting in the waves. They can be

displayed clearly only at very close range.

The characteristics of a target's echo changes

with radar range scales and the proper radar scale should be selected in the

measurement. Generally, the accuracy of radar ranges is higher than radar bearings

and the target accuracy of short distances is higher than long distances. When the

target echo is located at the 2/3 radius of the screen, the accuracy is the highest. For

raster scan radar, the target echo closer to the edge of the screen is of higher

accuracy.


3-1 Radar position-fixing


Land

Radar shorelin

e Real

shoreline

Radar beam

Fig.3-3 Land echo distortion

River entrance totally unseen

Beam width distortion

Pulse length distortion

Land

Island



Radar beacons are classified into navigational radar beacons and search and rescue

locating radar beacons according to their usual functions. The navigational radar

beacons are divided into passive aids and active aids.

.1 Passive aids (corner reflector and Luneburg lens reflector)

(1) Corner reflector

A corner reflector as shown in Fig.3-4 (a) is a device which reflects the incoming

waves back parallel along the incoming beam. Array corner reflectors can increase

reflecting ability at any horizontal angle and vertical angle. Fig.3-4 (b) is the chart

symbol of a corner reflector. A corner reflector is usually installed on a buoy, light

vessel, lighthouse, over a waterways cable, sea crossing bridge, lifeboat and other

important targets at sea.

(2) Luneburg lens reflector

The Luneburg lens reflector is a dielectric sphere with a

permittivity varying with the distance from the centre.

Paraxial rays can be focused at a point and reflect along the

direction of the incident, as shown in Fig.3-5. They increase

the RCS (radar cross-section). However, it is rare nowadays

due to its high cost and complex technique process.

.2 Active aids (Racon, echo enhancer and AIS AtoN)

(1) Racon

Racon (Radar Beacon) is mainly used to increase the ability of radar to detect targets,

such as buoys and landmarks. The MSC. 192(79) only require X-band radars to be

able to detect Racon. Racon is applied to coastlines with no obvious properties, sea

and land mark, gentle coastal land, precautionary area, centre line, waypoint of TSS,

dangers, channel under bridge, drilling platform, etc.

(2) The Radar Target Enhancer

The Radar Target Enhancer (RTE) is a device that receives, amplifies, and relays the

radar pulse, which is used to enhance the RCS of a target. It is mainly used for buoys

and small vessels.

(3) AIS AtoN

AIS AtoN is usually installed on important navigational facilities. It can increase the

information of this facility and radar detection range. AIS AtoN (AIS Aids to Navigation)

includes real AIS AtoN, Synthetic AIS AtoN and Virtual AIS AtoN. Real AIS AtoN is the

Fig.3-5 Principles of the

Luneburg lens

Incoming rays

Rays focused to this point To this point

Returning rays



navigational aid where the real AIS is installed. Synthetic AIS AtoN transmits AIS

navigational aid information from an AIS based station where the navigational aid

physically exists. Virtual AIS AtoN transmits navigational aid information from AIS

based station, but the navigational aid does not exist physically.

.3 Radar SART and AIS SART

(1) Radar SART

The SART operates in the 9 GHz frequency band (X band frequencies) and generates

specific response signals when triggered by the radar of this frequency band. Radar

display shows a line of 12 dashes with equal space outward from the SART's position

along its bearing. When the search and rescue radar approaches SART less than 1

nm, the 12 dashes will change to concentric arcs or even concentric circles as shown

in Fig.3-6. It is useful to warn the search craft to slow down and search the vicinity

carefully. The concentric arcs phenomenon can be weakened by reducing the radar

receiver's gain to determine the bearing of the survivors. If the clutter interferes with

SART signals, the SART signal can be observed clearly when the radar is set in

detune.

(2) AIS SART

AIS SART (Automatic Identification System Search and Rescue Transmitter) adopts

AIS technique to locate the survivor on the scene of search and rescue. According to

the SOLAS Convention, AIS SART is allowed to replace radar SART from January 1,

2010.

The AIS SART, once activated, can send static information, GNSS position

information and "SART ACTIVE" safety message. AIS SART broadcasts "SART

TEST" safety short message with fixed format in the test mode. AIS SART appears as

a cross surrounded by a red circle " " on radar displays. AIS SART identification

code is 970xxyyyy. AIS SART can be activated when the ship is in distress and the

distress messages will be transmitted one minute after being activated.

Normal echo 1 nm echo 300-500 m echo

Fig.3-6 Radar SART echo



.4 Data information of passive and active aids

(1) Corner reflector

The corner reflector can improve reflective performance. It is displayed on the radar

screen as an enhanced brighter spot than the original echo.

(2) Luneburg lens reflector

The Luneburg lens reflector increases the RCS,

and it is displayed on the radar screen as an

enhanced brighter spot than the original echo.

(3) Racon

Racon transmits the Morse code response after

receiving the ship radar searching pulse and the

Morse code is displayed on the radar screen

outward from the Racon's position along its

bearing, as shown in Fig.3-7. Racon appears only code information on radar screen at

long distances, while at short distances the Racon platform can be observed on the

radar screen.

(4) AIS AtoN

The AIS AtoN identification code is 99MIDxxxx and it appears as a diamond

surrounded by a cross at the beacon " " on the radar screen. Real AIS AtoN and

Synthetic AIS AtoN only display AIS icon at a long distance, and can display both the

echo and the AIS icon at a short distance, while they may not coincide completely and

may be offset with error. But virtual AIS AtoN can only display the AIS icon " "

without an echo on the radar screen.


The Parallel Index line technique can monitor the own ship's movement over the

ground uninterruptedly without radar fixing. Especially on the shorter range scales, it

is very sensitive in detecting deviation from the route plan. The instructor should be

informed whether the trainees understand the route plan and navigation in narrow

channels. The instructor can also illustrate by reference to the attached figures in this

sub-topic and explain it in class, if necessary.

.1 Establishment and use of parallel index lines

Fig.3-7 Racon

echo

Racon Platform

Racon Code



The direction and distance of a parallel index line can be set to keep the ship at a safe

distance from the shoreline and dangers, so that safe navigation can be achieved

easily.

As shown in Fig.3-8 (a) and 3-8 (b), the conspicuous targets with short distances and

accurate positions are chosen as reference targets and the distance (d) from such a

target to the planned route is measured. Adjust the radar to the relative motion

north-up presentation, set the VRM to distance (d), and make an EBL (electronic

bearing line) parallel to the route, tangent to the VRM on the same side of the target.

When the ship is underway, the OOW keeps the target echo moving along the

electronic bearing line, and ensure that the ship proceeds on its route. Early PPI

radars used the mechanical parallel index to achieve this function, while modern

radars use parallel index lines instead. It is suggested that the instructor use teaching

appliances for demonstration.

.2 Correct actions when the echo

deviates from the Pl line

When the ship deviates from its route, as shown

in Fig.3-9, the echo of a target departs the

parallel index line from position "a" to position

"a1". The own ship must alter course to port to

make the echo return to the parallel index line

which means making the ship go back to the

route.

A

B

C

Small island

d=3 nm a

b

c

(a) Choosing a conspicuous target near the route (b) Parallel index line

Fig.3-8 PI line on radar screen

Fig.3-9 Echo departs from the PI

line

a



.3 Use of multiple PI lines

As shown in Fig.3-10 (a), the ship is proceeding from A to D via points B and C and

the ship's track should be monitored.

As shown in Fig.3-10 (b), before the ship arrives at point A, switch on the radar, and

select north-up with the own ship at centre and range scale 12 nm. Draw the parallel

index lines ab, bc and cd of segments AB, BC and CD.

.4 Establishment and use of PI lines for

two range scales

As shown in Fig.3-11, when the target reaches

at point e, the operator can change it to the 6 nm

range scale. At this time, the echo of the target

appears at point e' and point e' starts to track

along the dotted line. Point f indicates the

position of "wheel over". When point g' on the 6

nm range scale is reached, if the operator

changes it back to the 12 nm range scale, the

echo will appear at point g. Thus the operator

can continue to use the parallel index line for

navigation.

.5 The importance of "wheel over"

The echo will deviate from parallel index lines bc and cd without the consideration of

manoeuvring characteristics of the own ship when the conspicuous radar target

a

b

d c

090

3 miles 054

B Small island

A

D

000

C

5.8 miles

(a) Multi-courses (b) PI lines on radar screen

Fig.3-10 More than one PI line

g'

g d c

e

a

b

f

e'

c' f'

Fig.3-11 PI lines for two range scales



reaches positions B and C and course alterations are made. Therefore, the "wheel

over" position must be calculated when using parallel index lines, as shown in

Fig.3-12.

.6 Demonstration of use of "wheel over"

As shown in Fig.3-13, when the target echo reaches the "wheel over" position, the

operator can use small rudder angles to turn the ship slowly to the new course.

.7 Safety margin

As shown in Fig.3-14, the planned course of the own ship is 054 and B'C' is the safety

margin line. This is drawn on navigational chart and the perpendicular distance

between BC and B'C' line is measured. Safety margin line (nav line) can be drawn

parallel to the PI line displaced by the same amount of the perpendicular distance

between BC and B'C'.

c'

e'

W/O2

Safety margi

n g'

3 nm

054 B

C

Small island

A

D

W/O1

W/O2

B'

C'

Fig.3-14 Safety margin

g d c

e

a

b

W/O2

Fig.3-15 Safety margin on screen

W/O

1

Fig.3-12 "Wheel over" position

090

3 nm

054

B

C

Small island

A

D

000 W/O1

W/O2

Fig.3-13 "Wheel over" on screen

Index target

should move

along this line

g d c

e

a

b

W/O2

e'

c'

054

g'

W/O1

W/O2



.8 Use of safety margin

As shown in Fig.3-15, set up a safety margin line next to the parallel index line, keep

the echo of the target so as not to exceed the margin line.

.9 Interpreting real motion of ship from a tracked echo

In using a true-motion presentation mode with a parallel index line, the radar picture

should be kept ground-stabilized. The ship proceeds from B to C on a course of 054 to

pass the radar target at a distance of 3 nm, as shown in Fig.3-16 (a).

Fig.3-16 (b) shows the radar true motion, ground-stabilized presentation, 6 nm range

scale, the realization method is as follows:

(1) Set the VRM as beam passing distance, i.e. 3 miles.

(2) Identify the conspicuous radar target.

(3) Draw the parallel index line b - c crossing the conspicuous target.

As the ship moves from position B to C, the VRM will roll along the parallel index line.

.10 Appropriate actions to counteract influence of currents

(1) On a straight course

As shown in Fig.3-17, in order to keep the ship on its planned route, the operator

should put the rudder to counteract the current when the current comes from the

portside.

(2) When ship is manoeuvring

As shown in Fig.3-18, draw a parallel of the new PI when the ship is passing "wheel

over" and determine the time to alter course according to the position of target echo.

3 miles

054 B

C

Island

(a) 3 miles off a radar conspicuous target (b) true-motion display for parallel

indexing

Fig.3-16 Real motion of ship from a tracked echo

3 miles

c

b

054

Steerin

g

course

Cons.

Target



.11 Use of line of turn

The distance of "wheel over" position can be approximately calculated by the

following formula:

)2

tan(DwheelCR (3-1)

Where, R is radius of turn (nautical mile), generally it is the minimum distance to fixed

target, ΔC is the angle of course alteration (degree).

The required ship's rate of turn along the arc can be calculated by the following

empirical formula:

RVw (3-2)

Where, w is rate of turn (degrees per minute); V is ship's speed (knot); R is radius

(nautical mile). The ship will follow the desired arc as long as the constant rate of turn

is maintained. It should be noted that the ship cannot alter course instantaneously,

and shallow water will increase the turning diametre, and the turn will cause speed

reduction.

As shown in Fig.3-19, the minimum distance between the route and fixed target is 3

nm, speed is 12 knots, and the course of alteration is 054. In this case, the ship's rate

of turn is 4° per minute and the distance to "wheel over" is 3×tan27°= 1.5 nm.

.12 Establishment and use of PI lines for radial turns

As shown in Fig.3-20, the operator can draw the line of turn on radar screen crossing

the "wheel over" position and make radial turns by monitoring the position of the target

echo.

Fig.3-17 Appropriate action to counteract current on a straight course

e'

c'

054

g'

W/O Safety margi

n

Steering

course

Fig.3-18 Appropriate action to counteract currents when vessel is manoeuvring

054

Steering

course

c

Vessel alters late

Vessel alters early

d

Parallel to new index

line




3-2 PI line navigation

3.4 Maps, Navigation Lines and routes for radar navigation (as fitted)

The operator is able to manually establish or revise, save, load and display maps,

navigation lines and routes relative to the own ship or a certain geographical position.

A planed route can also be called and removed from GPS or other route planning

equipment. The specific symbol for maps can be used to mark shoals, wrecks, reefs

and other underwater obstacles on the screen which cannot be detected by radar, and

also can be used to set navigation limit in channel, traffic separation schemes, etc.

The operator can remove these data easily through some simple operation. The

instructor can describe this in combination with simulator operation.

.1 Use of maps, navigation lines and routes

Maps, navigation lines and routes consist of lines, symbols and reference points, and

the appearance, colours and symbols meet the requirements of SN/Circ. 243. The

position of maps/navigation lines/routes can be set with reference to the own ship's

Fig.3-21 Radar map navigation

Approximate

coastline

Waypoints

Shoals Anchorage

Separation

zone

Planned route

Route alarm

line

Heading line

North marker

c

a

b

054

W/O

Fig.3-20 Pl for radial turns

054

B

A

000

C

Fig.3-19 Line of turn



position or a certain geographical position. Corresponding symbols of wrecks, reefs,

shoals and other underwater obstacles should be established according to their

geographical positions. The established maps/navigation lines/routes can be revised

and saved if necessary.

The operator can draw the simple navigational maps defined by the user on the radar

screen and personalize the navigation by setting the planned route of the own ship

and depicting the shoal limit line, anchor position and other specific symbols in the

ground-stabilized presentation, as shown in Fig.3-21.

.2 Removing maps, navigation lines and routes

The maps/navigation lines/routes should not significantly clutter the radar information.

The radar maps may cover the echoes, small fishing boats and some weak targets.

The operator must keep the radar screen clear by activating or removing a certain

kind of mapping element according to the navigational requirements and also

consider the requirements of radar navigation and radar observation. The mapping

elements can be removed temporarily by using the "synthetics off" button and can

also be removed by using the "maps off" button, which makes the targets hidden in

the mapping elements more easily observable.


3-3 Radar maps, navigation lines and routes navigation

3.5 Electronic chart overlay on the radar picture

In the operational display area, the radar system provides the method of displaying

the ENC and other vector chart information and continuous and real-time ship position

monitoring. The electronic chart information display can be eliminated by a one-button

operation.

The ENC display and other vector chart information is an optional function of radar

according to resolution MSC.192(79) PS. The ENC data that meet the IHO relevant

standards are the basic source of information, while the other chart information

sources should be marked permanently. The data sources and correction information

can be acquired.

There could be a difference between the radar representation of the coastline and the

coastline as underlayed on the electronic chart, especially in low coastlines. The

trainees should be made aware of this difference.

.1 ENC and other vector chart information display

(1) Display electronic chart when radar is in transmitting status. (must be north-up or

course-up presentation.)

(2) Electronic chart information adopts the same datum and coordinate system with

radar/AIS including datum, scale, orientation, reference point and stabilization mode.



(3) The ENC information appropriate to the prevailing circumstances and conditions is

selected according to category or layer, and radar information should be displayed

first. ENC information display should not cover, mix up or weaken radar information

significantly.

.2 Switching off electronic chart display on radar screen

Radar is used as the main electronic navigational aid to assist collision avoidance.

The ENC information should not obstruct the OOW in assessing the situation. A

one-button operation can remove electronic chart display information on the radar

screen.

.3 Picture frozen alarm and signal source or sensor failure alarms

(1) Picture Frozen alarm

Radar hardware, software, or sensor failure may result in frozen radar pictures as

radar images cannot be updated in a timely fashion. The visual alarm (ALARM ACK

key blinks in red) and audible alarm are activated in case of the picture becoming

frozen. The audible alarm will be cancelled when the "ALARM ACK" button is pressed

down, but the visual alarm will continue until the cause for alarm is no longer present.

(2) "Signal source or sensor failure" alarms

Any failure of signal sources or sensors, including the THD sensor, SDME sensor,

and EPFS sensor will trigger the alarm. The audible alarm is cancelled when the

"ALARM ACK" button is pressed down.


3-1 Radar position-fixing (1.0 h)


Through the instructor's demonstration and the trainees' practical training, the

objective is to help the trainees to attain sufficient knowledge of radar position-fixing,

to understand the echoes' characteristics of different targets, to grasp the method of

improving measurement accuracy, and identifying the causes of errors.

(2) Training mode

(a) Trainees complete the typical training programmes on the simulator set by the

instructor.

(b) Training programmes may include isolated island or two or more targets

appropriate for position-fixing.


The measurement of range and bearing (0.3 h)

Position-fixing on the chart, including single target range/bearing fixing; multi-targets

ranges fixing; multi-targets bearings fixing; multi-targets mixed fixing; (0.5 h)

Comparing radar position with GPS position (0.2 h).




3-2 PI line navigation



objective is to help the trainees establish and use PI in various navigation

environments and be acquainted with the key factors which can affect navigational

accuracy in the practical training process.

(2) Training modes


instructor.

(b) Training scenarios include isolated island or dangerous water areas.


Set up parallel index lines (0.3 h);

Use PI for navigation (0.8 h)

Use PI to alter course (0.7 h);

Set safety margin (0.2 h).


3-3 Radar maps, navigation lines and routes navigation (as fitted)



objective is to help the trainees attain relevant knowledge of radar maps, navigation

lines and routes navigation and develop the ability to ensure safe navigation by using

modern navigational aid.

(2) Training mode


instructor.

(b) Training programmes include TSS, reefs, shoals, anchor position and other targets

that cannot be detected and training in respect of waters where there is heavy traffic.




(a) Establish maps (marks/lines) (0.5 h)

Establish maps relative to the own ship (marks/lines)

Select suitable marks/lines according to the type of target;

Enter "maps" interface;

Move cursor to the proper position according to the target's range and bearing relative

to the own ship, and establish specific marks/lines on radar screen.

Establish maps (marks/lines) relative to the geographical position:

Select suitable marks/lines according to the type of target;

Enter "maps" interface;

Select the geographical position input mode (L/L) as the marks/lines input mode, and

input the latitude and longitude of targets;

Move cursor to the proper position according to the target's range and bearing relative

to the own ship, and establish specific marks/lines on the radar screen.

(b) Change maps (marks/lines) (0.3 h)

Move a certain of marks or lines individually;

Remove a certain kind of marks or lines individually;

Correct a certain kind of marks or lines individually;

Remove a certain kind of marks or lines collectively.

(c) Save maps (marks/lines) (0.2 h)

Select "file management" function button in "maps" menu after establishing maps

(marks/lines);

Select "flash card" position in "file management" function area;

Select "save" menu;

Input file name;

Select "save" button.

(d) Load maps (marks/lines) (0.2 h)

Enter radar mapping interface and select "file management" function button;

Select "flash card" position in the "file management" function area;

Select "flash card mark display" button;

Select the file to be loaded.



(e) Display maps (marks/lines) (0.2 h)

Display (switch on) maps (marks/lines) individually;

Set mapping display by type and activate maps by type (marks/lines);

Set mapping display by colour and activate maps by colour (marks/lines);

Set the marked font size; the marked fonts can be displayed in small size or standard

size;

Set the font size of notes; the font can be displayed in small or standard size.

(f) Establish routes (0.5 h)

Establish the waypoints according to the latitude and longitude;

Planned route, plan the route between the waypoints (automatically calculated);

Planned speed, plan the speed between the waypoints (manual input);

Set (arrival) waypoint alarm circle;

Set route (deviation) alarm line, the alarm line display the distance from the planed

route to determine the deviation alarm.

(g) Remove maps (marks/lines) (0.1 h)

Remove (switch off) a certain kinds of maps (marks/lines).

Remove (switch off) all maps (marks/lines).

Remove maps (marks/lines) temporarily. The "graphics off" function of the advanced

radar sets can make the graphics (including maps, marks, lines and routes) on the

radar screen temporarily hidden except VRM, EBL, HL and range rings, so as to

facilitate the observation of targets that may be influenced by the graphics.



examination, oral test, practical demonstrations, exercise scenarios, discussions and


performance. Focusing on radar position-fixing and navigation skills in this topic, the

trainee should:

(1) have comprehensive theoretical knowledge and practical ability to conduct radar

position-fixing; and

(2) use parallel index lines, maps, navigation lines, routes and ECDIS for navigation.



Teaching guidance

Radar position-fixing and navigation is a major duty for officers in charge of a

navigational watch. While in class, the instructor must emphasize that there are

corresponding methods for position-fixing and navigation in different radar

presentations. Also it must be stressed that, in the present context of position-fixing,

navigation and timing (PNT) system with high precision, the radar position-fixing and

navigation possess a quality of autonomy and irreplaceability. Trainees should be

reminded that nowadays OOWs have the tendency to reduce the use of the full

functions of the radar for navigational purposes since they do not have enough

practice to update their knowledge. It is necessary to raise awareness of

information-integrated navigation to make full use of all the functions of radar

position-fixing and navigation to ensure navigational safety.

(1) Regarding radar position-fixing method, the following should be highlighted:

It is of high accuracy for radar range measurement but low for bearing measurement.

When the target is close, the radar range measurement accuracy is high, but the

bearing measurement accuracy is high when the target is far; multi-targets range

fixing should be used if practicable; position-fixing operation should be done as

quickly as possible.

(2) In order to improve the accuracy of PI navigation, targets close to the ship's beam

should be chosen if practicable. Targets should be renewed in time when it comes to

a long route.

(3) In the use of maps, navigation lines and routes, layers should be selected

according to the prevailing circumstances and conditions so as to reduce the shades

of the radar picture. Attention should be paid to the following:

Maps, navigation lines and routes may obstruct small targets, such as small

fishing boats. These maps, navigation lines and routes should be removed at

appropriate intervals temporarily according to prevailing navigational circumstances

and conditions at that time.

When maps, navigation lines and routes are established, types and colours

of the marks/lines should be selected according to different targets, in order to

activate or remove some particular marks/lines to keep the radar screen clear.

(4) When the ENC is loaded, position references should be checked and radar

pictures should overlap with electronic chart completely. If the ENC information

interferes with radar function, it should be cancelled immediately.

(5) Plans for the practice exercises should be targeted, enabling the trainees to

develop a good knowledge and understanding of using parallel index line, maps,

navigation lines and routes while keeping proper lookout and conducting radar

observation and position-fixing. The instructor should monitor and supervise the

whole process. At the end of the training, the instructor should review and evaluate

the performance of the trainees, and point out the key points in operation.



4 Manual radar plotting


This topic mainly includes the basic principles of manual radar plotting and the

application of these principles to acquire the motion elements of the target ship and

the changes to its course and speed.

Manual radar plotting is based on the basic operation of radar and the results can be

used in ship collision avoidance.


.1 Meanings of relative motion triangle, various vectors and angles

A relative motion triangle consists of the own ship's true vector, target ship's true

vector and the relative motion vector.

The own ship's true vector indicates the speed and course of the own ship's true

motion. Target ship's true vector indicates the speed and course of target ship's true

motion. The relative motion vector indicates the speed and direction of the target

echo's movement observed in relative motion presentation.

In the relative motion presentation, the extension line of the target's track within a

period of observation time is the relative motion line (RML) of the target; the direction

of motion is the direction of the relative motion vector of the target ship; the moving

distance is the length of the relative motion vector. Relative motion vector indicates

the movement tendency of target echo on the radar. The distance from the radial scan

centre (position of the own ship) to the RML can indicate possible risk of collision of

the target ship and the own ship.

.2 Construction of relative motion triangle on plotting chart

The relationship of these three vectors in a relative motion triangle is shown in formula

4-1 and Fig.4-1:

rvovtv (4-1)

where

ov —— the own ship's true vector;

tv —— target ship's true vector;

rv —— relative motion vector.




.1 Measuring range and bearing of a target ship at an appropriate interval and frequency

(1) The bearing and range of a target echo on radar can be measured in this way: the

range of target can be obtained by making the inner edge of VRM tangent with the

inner edge of target echo on the radar. The bearing as indicated by the EBL on the

tangent point is the bearing of the target. The bearing and range can be obtained

simultaneously by the ERBL on modern radar.

(2) To ensure accuracy, the range and bearing of the target ship should be measured

at a frequency of three times or more, and with equivalent intervals of normally 3 or 6

minutes. If the observed positions of these target echoes on the plotting chart are

equally spaced on one line, it indicates that the own ship and the target ship both keep

their courses and speeds during the observation period.

.2 Determination of course, speed and aspect of a target ship in relative presentation modes (stabilized or unstabilized)

(1) The course and speed of a target ship in a relative

presentation can be obtained as shown in Fig.4-2.

(a) Plot the observed positions (E1, E2, E3) of the target

ship on the plotting chart.

(b) Start from the starting position of the target ship (E1)

first, then plot the reciprocal distance (E1W) that the

own ship travelled through the water during the

observation, and finally connect it to the end position of

the target ship (E3).

Then, the length of WE3 is the moving distance of the

target ship in the observation intervals. Thus the speed

of the target ship can be calculated, with the direction

of WE3 as the course of the target ship.

(2) Aspect can be obtained as indicated in Fig.4-3

(a) Obtain the true vector of target ship 3WE as

mentioned in (1) above.

E1

Fig.4-2 Relative motion plotting

E

2

E

3 W

Fig.4-3 Aspect

E1

E2 E3 C

W

O



(b) The angle ∠CE3O, which is the angle between the extension line E3C of 3WE and

the bearing line OE3, is the aspect.

.3 Determination of course, speed and aspect of a target ship in true presentation modes

(1) The course and speed of a target ship in true presentation mode can be obtained

as shown in Fig.4-4.

(a) Draw the route of the own ship on plotting chart based on its course.

(b) Plot positions (W1, W2, W3) of the own ship on the route corresponding to the

observation time.

(c) Plot positions (E1, E2, E3) of the target ship based on the observed bearing and

range corresponding to positions of the own ship on the plotting chart.

Then, the length of E1E3 is the moving distance of the target ship within the

observation interval. The speed of the target ship can thus be calculated and the

direction of E1E3 is the course of the target ship.

(2) The aspect can be determined as shown in Fig.4-4.

(a) E3C is the extension line of target route E1E3.

(b) Angle ∠CE3W3, which is the angle between the course of the target ship and the

bearing line, is the aspect.

.4 Factors affecting accuracy of derived course, speed and aspect

The factors that affect the accuracy of plotting include:

(1) Inappropriate mode of radar presentation;

(2) Error of observed bearing and range of target ship;

(3) Error of the own ship's course and speed;

(4) Inappropriate plotting scale, error of plotting and calculation.



.5 Determination of set and drift of current by observing a fixed target

The set and drift of current can be obtained by the observation of a fixed target, as

shown in Fig.4-5.

(1) Plot the echo of a fixed target (E1, E2, E3) on the plotting chart.

(2) Draw the relative motion triangle (△E1WE3) in the same

way of obtaining the course and speed of target ships by

relative motion plotting as mentioned above.

Thus, the length of E3W is the drifting distance of current in

the interval of observation. The drift of current can thus be

calculated, but the direction of WE 3 is the drifting direction,

i.e. the set of currents.


.1 Determination of CPA and TCPA in relative presentation modes (stabilized

and unstabilized)

CPA and TCPA of a target ship in a relative

presentation can be obtained as shown in Fig.4-6.

(1) Plot the observed positions (E1, E2, E3) of the target

ship on the plotting chart.

(2) Get the RML (E1E3) of the target ship by connecting

these positions and extend the line towards the direction

of E1E3.

(3) Draw a perpendicular from the own ship's position O

to the extension line until the foot point P.

Then, the length of OP is CPA and the time needed for

the target ship to arrive at the foot point P is TCPA.

.2 Determination of CPA and TCPA in true presentation modes

CPA and TCPA of a target ship in true

presentation can be obtained as shown in

Fig.4-7.

(1) Plot the course and speed of the target ship

in a true presentation as mentioned above.

(2) Plot the relative motion triangle (△E1EE3)

based on the track (E1E3) of the target ship, and

obtain the RML (EE3) of the target ship.

Fig.4-5 Set and drift of current

E1

E2

E3 W

Fig.4-6 CPA and TCPA from RP

E1 E1

E2

E3

P O



(3) Draw a perpendicular from the own ship's corresponding position W3 to the

extension of the RML EE3, and obtain the foot point P.

Then, the length of W3P is the CPA, and the time needed for the target ship to arrive

at the foot point P is the TCPA.

.3 Factors affecting accuracy of CPA and TCPA

The factors that affect the accuracy of CPA and TCPA include:

(1) Inappropriate mode of radar presentation;

(2) Error of observed bearing and range of targets;

(3) Inappropriate plotting scale, error of plotting and calculation.


4-1 Acquiring motion elements of target ships


.1 Effects of course alteration and/or speed change of a target ship

Course alteration and/or speed change of a target ship normally leads to changes of

initial CPA and TCPA when the own ship keeps its speed and course.

As shown in Fig.4-8, 3WE is the true vector of the target ship. The target ship turns to

starboard with angle α (with no speed change) at the moment E3 while the own ship

keeps the course and speed. Then the RML changes accordingly, which means

changes of CPA, TCPA, relative course and speed of the target ship. Similarly, effects

of changes in CPA, TCPA, relative course and speed of the target ship can be

obtained while it keeps course but changes speed or changes both course and speed.

Fig.4-8 Plotting of the relative motion vectors for both ships

(The target ship making a turn while the own ship keeping the course and speed)

W α

E3'

W

W

P

P1

E1

E2

O

E3



.2 Radar observation vs. visual look-out

Radar observation has advantages for long range targets and high measurement

accuracy and it is less influenced by visibility. Although motion elements of a target

ship can be obtained by radar plotting, it takes a longer time. In terms of finding a

target ship manoeuvre, there exists a time delay. It is difficult to find small course

alterations and/or speed changes in particular.

Visual look-out is the most basic and important means to maintain a proper look-out

for officers and bridge crew. It should never be neglected. Visual look-out is simple,

convenient and immediate, which helps officers to make a full appraisal of situations

and risks of collision, but accuracy is poor in estimating target ship motion elements.

Visual look-out could be easier than radar observation in finding a manoeuvre of the

target ship earlier according to the course alteration and/or speed change.

.3 Time delay between change of course or speed and detection of that change

Through continuous observation, course alteration and/or speed change of a target

ship can be obtained from the change of the RML. But it is difficult to estimate

changes of course and speed of target ships within a short observation time, because

the change of the RML of target ships is not obvious in such situations. Therefore,

there should be enough continuous observation time for detection of the changes in

target course and speed.

.4 Advantages of bearing stabilization in relative motion display

In order to determine the risks of collision and ensure the stability of the radar picture

after taking collision avoiding actions, manual radar plotting in a relative presentation

mode with bearing stabilization is normally applied. This display mode is conducive to

reducing error and improving plotting accuracy. Moreover the echo of the target ship

remains steady and continuous when the own ship alters course.

.5 Effects of changes in own ship's course or speed on the observed movement of target

As shown in Fig.4-9, the new RML changes when the own ship makes a turn to

starboard with an angle of α at moment E3 (with no speed change), which also leads

to the subsequent changes of CPA, TCPA, as well as the relative course and speed of

the target ship. Similarly, it is also possible to obtain the changes of new CPA, TCPA,

relative course and relative speed while the own ship changes speed alone or

changes both speed and course.



Fig.4-9 Relative movement vectors of both ships

(The own ship making a turn while the target ship keeping her course and speed)

.6 Effects of small changes of course and/or speed on detecting change and change accuracy of true vector

It is more difficult to find small changes of true vector of a target ship compared with

large changes when manual radar plotting is used to detect change and change the

accuracy of the true vector of the target ship.

The changes of the true vector of the target ship are presented by changing RML on

radar plotting. When both ships have similar speeds, it is difficult to detect the

changes of RML if the target ship has small changes in course or speed. Therefore,

adequate collision avoidance actions should be taken in order to be detected by other

ships. A large alteration of course or reduction in speed should be made so that it is

readily apparent to the other vessels in the vicinity.




The importance of manual radar plotting should be fully understood and procedures of

the manual radar plotting report should be made clear.

The manual radar plotting report should include the following data, namely, bearing,

range, CPA, TCPA, course, speed and aspect.

The report should start from finding a target on radar, and then bearing, range, CPA,

TCPA, course, speed and aspect. Continuous observation should be maintained and

the frequency of reporting should be adjusted with the development of the situation.

Following the collision avoidance action, reporting should be maintained until the

other ship is finally past and clear.

3E

2E

1E1'E

W1P

P

O




Demonstration and practical training 4-1 Acquiring motion elements of target ships


With this training, trainees should understand the meaning of relative vector triangle,

different vectors and angles and also should know how to acquire the course, speed,

aspect, CPA and TCPA of target ships. Moreover, trainees should know the factors

affecting the accuracy of motion elements, which is the basis of learning how to avoid

collisions with target ships by radar in further study.

(2) Training mode

Demonstration and practical training should be carried out on radar simulators.


(a) Power on radar and adjust the radar simulator to its optimal display status.

(b) Plot the motion elements of target ships on plotting charts based on radar

observation.

(c) Training report

Own ship Target ships

Course Speed

Data of observation Motion elements

Time Bearing Range Course Speed CPA TCPA Aspect

(4) Training guidance

(a) Instructors

I. Requirements of training scenarios: target ships may include ships with same speed

and course, anchoring ships, head-on ships, crossing ships, overtaking ships and

ships being overtaken, etc. At the same time, the target ships should be located at

different bearings of the own ship.

II. Demonstrate the right methods of using manual radar plotting tools.

III. Demonstrate the ways to plot the positions of target ships on plotting chart and

ways to acquire the motion elements.

IV Summarize and assess the performance of trainees at the end of the training.

(b) Trainees

I. Pay attention to the difference of bearings in different radar presentations.

II. Keep course and speed while plotting.



III. Note that too short intervals of observation may cause major deviation while too

long intervals may prolong the plotting time.



Based on in-depth class discussions, trainees should be able, by means of

demonstration and practical training, to attain the knowledge regarding the influences

of the own ship's course alteration on CPA, TCPA and the RML, and acquire the skills

of altering course to avoid collision in different situations.

(2) Training mode




(b) Take collision avoidance actions in different encounter situations based on radar

observation.

(c) Record the changes of the RML after each course alteration and analyse the

changes of RML following the own ship's actions towards different target ships.

(d) Training report

Own ship Target ships Course change action

Course Speed No. Bearing Range New Course Change direction of RML

1

2


(a) Instructor

I. Requirements of training scenarios: target ships may include ships with the same

speed and course, anchoring ships, head-on ships, crossing ships, overtaking ships

and ships being overtaken, etc. At the same time, the target ship should be located at


II. Demonstrate how to take collision avoidance actions by altering the course on

radar simulator, as well as how to maintain course and speed.

III. Demonstrate the ways to determine the changing direction of RML after taking

collision avoidance actions.



IV. Summarize and assess the performance of trainees at the end of the training.

(b) Trainees

I．In order to manifest the influence of course alteration on RML, the own ship can turn

to starboard or port side.

II．During the simulation training, the target ship should keep its speed and course and

the own ship keeps its speed.

III．After course alteration, the course and speed of the own ship should be made

steady as soon as possible.



Based on in-depth discussion in class, trainees should be able, by means of

demonstration and practice, to attain the knowledge regarding effects of the change of

the own ship's speed on CPA, TCPA and the RML, and acquire the skills of changing

speed to avoid collision in different situations.

(2) Training mode

Demonstrations and practical training will be carried out on radar simulators.



(b) Take collision avoidance actions in different encounter situations based on radar

observation.

(c) Record the changes of the RML after taking each change of speed to avoid

collision and analyse the changes of RML following the own ship's actions towards

different target ships.

(d) Training report

Own ship Target ships Speed change action

Course Speed No. Bearing Range New

speed

Change direction of

RML

1

2


(a) Instructor

I. Requirements of training scenarios: target ships may include ships with the same

speed and course, anchoring ships, head-on ships, crossing ships, overtaking ships



and ships being overtaken, etc. At the same time, the target ship should be located at


II. Demonstrate how to take collision avoidance actions by changing the speed, as

well as how to maintain its course and speed.

III. Demonstrate the ways to determine the direction of RML change after taking

collision avoidance actions.

IV. Summarize and assess the performance of trainees at the end of the training.

(b) Trainees

I．The own ship can speed up or slow down in order to manifest the influence of speed

change on RML.

II．During the simulation training, the target ship should keep speed and course and

the own ship maintains its course.

III．After changing speed, the own ship should make the course and speed steady as

soon as possible.



Through demonstration and practice, trainees should be able to understand the

importance of manual plotting report and make clear the contents of the report and the

procedures of the operation.

(2) Training mode



(a) Measure the range and bearing of the target ship by radar observation.

(b) Acquire course, speed, CPA, TCPA of target ships by radar plotting.

(c) Report the manual plotting data according to the reporting procedure.


(a) Instructor

I．Demonstrate the manual plotting report procedures including report contents and

frequencies which change with situations.

II．Summarize and assess the performance of the trainees after the training.



(b) Trainees

Continuous observation should be maintained. The reporting frequency should be

adjusted with the changes of the situation and the reporting should be maintained

after taking collision avoidance actions and until the target ship is past and clear.



examination, oral test, practical demonstration, exercise scenarios, class discussions

and records, etc. in order to assess whether a trainee satisfies the required

performance. Focusing on the basic concept of vector triangle in collision avoidance

and the formation of motion vectors in encounter situations in this topic, the trainee

shall

(1) have the primary knowledge and practical ability to determine the motion elements

of target ships by fast plotting under the relative or true motion presentation;

(2) interpret the effects of the action to avoid collision on the RMLs of target ships; and

(3) complete the procedures of manual radar plotting reports correctly.

Teaching guidance

This topic is mainly about the technique of manual radar plotting and its application.

After the learning, demonstration and practical training, trainees should develop an

expertise of manual radar plotting technique and establish the concept of relative

motion. Knowledge regarding the effects of collision avoidance actions on CPA and

TCPA should also be acquired.

It should be highlighted that even with the comprehensive auto-tracking functions of

radar, it is still important for the officer in charge of a navigational watch to acquire

manual plotting knowledge and skills. The principles and approaches are the

theoretical foundations of radar target tracking technique. Expertise of manual plotting

is conducive to the establishment of a complete concept of vector triangle in collision

avoidance and the formation of motion vectors in encounter situations. This in turn

assists full comprehension and application of ARPA in providing collision avoidance

information. It should be particularly highlighted that trainees should make clear

assessments regarding the CPA changes and developments of target ships based on

the patterns of RML changes so as to predict the effects of collision avoiding actions

for the benefit of the coordination of ships encountered.

The concept of vector triangle is the key point of this topic. The instructor should try all

effective means to assist the trainees in establishing the concept of vector triangle so

that they may develop a comprehensive understanding of the effects on CPA and

TCPA of motion vector changes of both the own ship and the target ship. Automatic

target tracking and AIS reporting functions may be integrated in the instruction of



plotting principles and approaches to strengthen trainees' understanding of vector

triangle. Detailed interpretation and analysis should be made regarding different

encounter situations between ships, such as the same speed and course ships,

anchoring ships, head-on ships, crossing ships, overtaking ships and ships being

overtaken.

In this topic, situational awareness is emphasized. Demonstration and practical

training should be the focal parts in the whole process. A training plan should be

developed by instructors with considerable navigation experience. Real-time plotting

practices on radar simulators may help the trainees to develop good understanding of

plotting geometry and relative motions, thus improving their plotting techniques.

The instructor should play a leading role in delivering the course. Demonstration of the

plotting procedures should be based on detailed explanations. Effective training can

be achieved by frequent practices on radar simulators. In this topic, demonstration

and practical training should be designed step by step from the easier to the more

complex. Trainees could begin from the simplest exercise, and make gradual

progress to meet the requirements of the STCW Convention. Demonstration and

practical training may be conducted in conjunction with classroom instructions or

conducted after the instructions. Practical training time for trainees should be no less

than three quarters of the total demonstration and practical training time.



5 ARPA system or radar target tracking (TT) and AIS reporting functions


The ARPA system or TT and AIS reporting functions can obtain collision avoidance

information between targets and the own ship. Based on resolution resolution

MSC.192(79), Performance Standards, ARPA has evolved from a stand-alone

automatic radar plotting aid to an essential and indispensable functional module in

radar video data processing, which is referred to as TT. The AIS sensor provides

information of AIS reported targets to assist collision avoidance.

This topic deals with radar application for collision avoidance which is a significant

part of safe navigation. The teaching objectives include:

(1) The display characteristics of radar tracking targets;

(2) The display characteristics of AIS reported targets;

(3) The basic concept of the association of radar tracked targets with AIS reported

targets;

(4) IMO performance standards for ARPA or TT and AIS reporting functions;

(5) Criteria for acquisition of ARPA or TT targets and activation of AIS reported targets;

(6) Radar tracking capabilities and limitations;

(7) Processing delay of ARPA or target tracking and possible information delay of AIS

reported targets.

This topic, based on the theoretical foundation established in Topics 1 and 4, enables

trainees to develop a full understanding of the principles of ARPA and TT and AIS

reporting functions. Effective use of ARPA or TT and AIS reporting functions helps

them to perform the watchkeeping duties competently.


.1 Vectors

Originating from the target position (target tracking position or AIS reported position)

and the CCRP position of the own ship, vector is a line segment to predict the motion

of the target and the motion of the own ship within a specific period (the length of time

can be adjusted by the operator). Specifically, the direction of the line segment

represents the motion direction of the target and the motion direction of the own ship,

and the length of the line segment is the predicted motion distance in the set period.

Therefore, once the unit time is selected, the length of the vector will represent the

predicted speed of the target.



With vectors, the operator can quickly obtain the target's motion trends, evaluate

collision risks, interpret the encounter situations, determine and take measures to

avoid collision.

Vector modes include relative vector (RV) and true vector (TV).

(1) Relative Vector

(a) The meaning of relative vector

The originating point of the relative vector is the current position of the target and the

direction represents the motion direction of the target with respect to the observing

ship; the length of the vector represents the motion distance within the set time with

respect to the observing ship; and the tail end of the vector indicates the relationship

of the position between the target and the own ship after the set time (provided there

are no manoeuvres for the observing ship and target ship within the set time).

(b) Features of relative vector

I．The relative vector is the target motion vector with respect to the observing ship and

the extension of the relative vector and is essentially equivalent to the target Relative

Movement Line (RML), as T1 and T3 shown in Fig.5-1 (a) and (b).

(a) RM. RV.

T4

T3

T2 T1

T1

T4

T3 T2

(b) TM. RV.

(c) RM. TV. (d) TM. TV.

CPA LIM

T4

T3 T2 T1

TCPA CP

A

T4

CPA LIM

T3

T2 T1

CP

A

TCPA

CCRP

CCRP

CCRP

CCRP

Safe

Safe

Dangerous

Dangerous

Fig.5-1 The relative vectors and true vectors



II．In the water area not affected by wind and current, the direction of the relative

vector of a fixed target is opposite to the compass course of the observing ship and

the velocity value represented is equal to the speed value of the observing ship, as T4

shown in Fig.5-1 (a) and (b). While in the water area with wind and current, the

direction of the fixed target relative vector is opposite to the track of the own ship, and

the value is equal to the tracking speed of the own ship.

III．There is no relative vector on the own ship as shown in Fig.5-1 (a) and (b), and

targets possessing the same speed and course with the own ship have no relative

vectors as well, as T2 shown in Fig.5-1 (a) and (b).

IV．The perpendicular line segment from the own ship to relative vector or its

extension line is called CPA and the target navigation time from the start point of the

target relative vector to the perpendicular foot is TCPA, as shown in Fig.5-1 (a) and

(b).

V．The relative vector and radar orientation modes (H-up, N-up and C-up) or motion

modes (TM, RM) are independent, as shown in Fig.5-1 (a) and (b).

(2) True vector

(a) The meaning of true vector

Both the observing ship and target ship have true vectors. The originating point of the

true vector is the current position of the target or CCRP of the own ship and the

direction represents the true course of the target or the observing ship. The length of

the vector represents the true motion distance within the set vector time, and the tail

end of the vector indicates the ship position after the set time (provided there are no

manoeuvres for both the observing and target ship within the set vector time).

(b) The features of true vector

I．Both the own ship and target ship have true vectors (It is assumed that the speeds

of the own and target ship are not zero). The ratio of the true vector lengths between

the own ship and the target ship is actually the speed ratio, as the own ship and

targets T1, T2, T3 shown in Fig.5-1 (c) and (d), among which T2 has the same speed

and course with the own ship.

II．The features of true vector depend on the own ship's speed input mode. When

SOG is selected, the true vector is the vector relative to the ground and radar pictures

are generally suitable for coastal and narrow waters taking consideration of both

collision avoidance and navigation. When STW is selected, the true vector is the

vector relative to water and the radar presentations are generally suitable for ship

collision avoidance. In the water area free of the effect of wind and current, the SOG is

equal to the STW. In other words, there is no deference between the true vector

relative to the ground and to the water.

III．There is no relationship between true vector display and radar orientation modes

(H-up, N-up and C-up), as well as motion modes (TM, RM), as shown in Fig.5-1 (c)

and (d).



Slides or other forms of visual presentation may be adopted in the course, with

emphasis on the significance of using vectors to obtain target predicted motion and

assess the risks of collision, so that the officers will be well informed of potential

encounter situations and take collision avoidance measures. Also it is important to

note that the alternate use of different modes of vector is significant for obtaining

comprehensive information about collision avoidance and that false vector

identification mode causes serious consequences.

.2 Graphics

For each radar tracked target, the following symbol graphics should be presented in

graphical form: radar acquired target, radar tracking target, and dangerous target.

The significance of familiarity with graphical symbols of radar tracking target should be

emphasized in the course. It is preferable that all symbol graphics in Table 2 of

Appendix I-7 be illustrated with live radar screenshots or the graphics illustrated in

radar operation manual.

.3 Alphanumeric data

The display of alphanumeric data of the tracked target required by IMO performance

standards include the relative range/bearing (or true bearing), CPA/TCPA, true

course/speed, and Bow Crossing Range (BCR)/Bow Crossing Time (BCT) which are

also available in many radar sets.

The relevant symbols and data of targets from radar should be clearly identified.

.4 PADs

PADs is an acronym for "Predicted Area of Danger", which is the possible collision

area of the own ship with the target under the condition that the target keeps the

speed and course and the own ship keeps the speed only.

PADs are not the required function by IMO performance standards. Due to the

complex graphical lines, the use of PADs is very limited in practice, and it is not

suitable for narrow waters, fishing areas, and coastal waters. Radar systems with the

PADs function have been uncommon in recent years.

(1) The features of PADs

PAD is presented as an arbitrary closed area. As an

example, the popular hexagonal PADs on radar

screens is shown as the symmetrical hexagon " " in

the true vector line, as shown in Fig.5-2. The axis

represents the true course line of the target and the

length of the axis is associated with the speed ratio of

the targets and the observing ship, and the width of

PADs is twice that of CPA LIM (limit).

(2) The relationship between PADs and vector

When switching over to PADs mode, only the true

T2 T1

O T0

Dangerous

Safe

Fig.5-2 PAD



vectors are displayed.

(3) The number of PADs

Different speed ratio and encounter situations between the own ship and targets will

lead to a variety of number of PADs, 0, 1, 2, as shown T0, T1 and T2 in Fig. 5-2.


AIS provides basic knowledge in the course. The instructor may review the basic

concepts of AIS in an interactive way, focusing on the fact that the radar display

terminal provides an optimum display platform for the application of AIS information in

collision avoidance.

AIS reported targets is a required function of radar according to resolution resolution

MSC.192(79), Performance Standards.

AIS reported targets should be presented with their relevant symbols according to the

performance standards for the Presentation of Navigation-related Information on

Shipborne Navigational Displays adopted by the IMO and propagated through

SN/Circ.243.

AIS targets that are displayed should be presented as sleeping targets by default.

.1 Vectors

The course and speed of AIS reported targets should be indicated by a predicted

motion vector. The vector time should be adjustable and valid for the presentation of

any target regardless of its source. AIS presentation status is specified in TABLE 4 of

Appendix I-3.

A permanent indication of vector mode, time and stabilization should be provided.

.2 Graphics

AIS reported targets should be identified with their relevant graphics. The AIS

reported target symbols are specified in Table 2 of Appendix I-7.

.3 Alphanumeric data

For each selected AIS target, ship information should be displayed in alphanumeric

mode as follows:

(1) Static information includes ship's name, call sign, MMSI, length and beam, and

type of ship.

(2) Dynamic information includes ship's position, heading, course, speed, ROT

(compulsory for all ships of 50,000 gross tonnage and upwards), CPA and TCPA, and

navigation status.

(3) Voyage related information includes ship's draught, destination, voyage plan, etc.



The information may inform the officer of the characteristics and movements of the

targets, so that they can assess the encounter situations and the risks of collision, and

take corresponding actions.

The current target data should be displayed and updated continually until another

target is selected for data display or the window is closed. In addition, a means is also

provided for presenting the own ship AIS data on request.

If more than one target is selected for data display, the relevant symbols and

corresponding data should be clearly identified.


.1 Concepts of association

As required by resolution MSC.192(79), Performance Standards, an automatic target

association function based on harmonized criteria avoids the presentation of two

target symbols for the same physical target.

The information on target positions, courses, speeds respectively from the radar

sensors and AIS sensors have various degrees of accuracy. Based on the association

criteria (e.g. time, position, course and speed), making full use of the information, the

radar optimizes and outputs the consolidated and optimal dynamic information about

the target as required by the officer. This process is called the association of radar

tracked targets with AIS reported targets.

.2 Independence and interdependency of radar tracked and AIS reported targets

(1) Independence

Radar target tracking information and AIS target reported information come from

different independent sources with independent communications and access

channels without synchronization. Thus there exist information errors. It is to be

noted that as per the performance standands (resolution MSC.192(79)), AIS target

has priority over ARPA target.

(2) Interdependency

For the same target, there exists a good interdependency between radar tracking and

AIS reported target information.

.3 Principles of association and factors affecting association

If the target data from AIS and radar tracking are both available and if the association

criteria (e.g. position, motion) are fulfilled, the AIS and radar information are

considered as one physical target. Then in a default condition, the activated AIS target

symbol and the alphanumeric AIS target data should be automatically selected and

displayed.



The instructor should point out that factors affecting association setting include traffic

density, the precision of the equipment and the accuracy of navigational instruments

affected by weather/sea conditions, etc., e.g.,

(1) In the open sea, the distance between ships is normally more than 1.5 nm. Even in

coastal waters with heavy traffic, it is generally not less than 0.8 nm.

(2) According to resolution MSC.192(79), Performance Standards (5.25.4.7.1) and

IEC 62388 standards, under the circumstance of ship rolling within ±10°, the

measured target range and bearing should be within 50 m or ±1% of target range,

whichever is greater, with a precision of 2°.

(3) The reported interval of AIS dynamic data may vary from the requirements of the

performance standards due to the fact that performance of equipment from different

manufacturers differs and that AIS VHF Data Link (VDL) environment varies.

(4) When a tracked target has achieved a steady state, the true speed accuracy of the

target is within 0.5 knots or 1% of target speed (whichever is greater) and the true

course accuracy is within 5° provided by radar tracker. But considering the actual sea

conditions, especially in adverse weather and rough sea conditions, the actual

tracking accuracy may be lower than the requirements of the standards.

5.4 Performance standards for ARPA or TT and AIS reporting functions

This sub-topic focuses on the related content of resolution MSC.192(79),

Performance Standards. For the ARPA system, please refer to Appendix I-5. Prior to

the instruction, relevant materials should be prepared and distributed to the trainees.

.1 Accuracy requirements for ARPA or TT

Automatic tracking accuracy should be achieved when the tracked target has

achieved a steady state, assuming the sensor errors are within the range specified by

the relevant performance standards.

For ships (HSC typically) capable of up to 30 knots true speed, the tracking facility

should present, within 1 min steady state tracking, the relative motion trend and after

3 minutes, the predicted motion of a target. The accuracy values (95% probability) are

specified in TABLE 3 of Appendix I-3.

Accuracy may be significantly reduced during or shortly after acquisition, a

manoeuvre of the own ship, a manoeuvre of the target, or any tracking disturbance

and is also dependent on the own ship's motion and sensor accuracy.

Measured target range and bearing should be within 50 m (or ±1% of target range,

whichever is greater) and 2°.

For ships capable of speeds in excess of 30 knots (typically High-Speed Craft (HSC))

and with speeds of up to 70 knots, there should be additional steady state



measurements made to ensure that the motion accuracy, after 3 minutes of steady

state tracking, is maintained with target relative speeds of up to 140 knots.

.2 Requirements for target acquisition and tracking

TT facilities should be available on at least the 3, 6, and 12 nm range scales. Tracking

range should be extended to a minimum of 12 nm.

Manual acquisition should be provided with provision for acquiring at least the number

of targets specified in TABLE 1 of Appendix I-3.

Automatic acquisition should be provided where specified in TABLE 1 of Appendix I-3.

In this case, the operator can define the boundaries of the auto-acquisition area.

When a target is acquired, the system should present the trend of the target's motion

within 1 minute and the prediction of the targets' motions within 3 minutes.

TT should be capable of tracking and updating the information of all acquired targets

automatically.

The system should continue to track radar targets that are clearly distinguishable on

the display for 5 out of 10 consecutive scans or the equivalent.

The TT design should be such that target vector and data smoothing is effective, while

target manoeuvres should be detected as early as possible.

The possibility of tracking errors, including target swop, should be minimized by

design.

Separate facilities for cancelling the tracking of any one and of all target(s) should be

provided.

Automatic tracking accuracy should be achieved when the tracked target has

achieved a steady state, assuming the presence of sensor errors allowed by the

relevant performance standards of the IMO.

A ground referencing function, based on a stationary tracked target, should be

provided. Targets used for this function should be marked with the relevant symbol

defined in SN/Circ.243.

.3 Requirements for operational alarms

Instructors may first introduce the significance of the ARPA or TT and AIS operational

alarms in ensuring the safety of navigation. Discussion of alarm criteria can be done

from the point of view of ensuring navigational safety, with an emphasis on the

necessity of a clear indication of the cause for all alarm criteria.

The preset CPA/TCPA limits applied to targets from radar and AIS should be identical.

If the calculated CPA and TCPA of a tracked target or activated AIS target are less

than the set limits,

(1) a CPA/TCPA alarm should be given;

(2) the target should be clearly indicated.



As a default state, the CPA/TCPA alarm functionality should be applied to all activated

AIS targets. On user request the CPA/TCPA alarm functionality may also be applied

to sleeping targets.

If a user-defined acquisition/activation zone facility is provided, a target previously not

acquired/activated entering the zone, or detected within the zone, should be clearly

identified with the relevant symbol and an alarm should be given. It should be possible

for the user to set ranges and outlines for the zone.

The system should alert the user if a tracked radar target is lost, rather than excluded

by a pre-determined range or pre-set parameters. The target's last position should be

clearly indicated on the display.

It should be possible to enable or disable the lost target alarm function for AIS targets.

A clear indication should be given if the lost target alarm is disabled.

If the following conditions are met for a lost AIS target:

(1) The AIS lost target alarm function is enabled.

(2) The target meets lost target filter criteria.

(3) A message is not received within a period of set time according to the nominal

reporting rate of the AIS target.

Then:

(1) The last known position should be clearly indicated as a lost target and an alarm

be given.

(2) The indication of the lost target should disappear if the signal is received again, or

after the alarm has been acknowledged.

(3) A means of recovering limited historical data from previous reports should be

provided.

.4 Requirements for alphanumeric data

It should be possible to select any tracked radar or AIS target for the alphanumeric

display of its data. A target selected for the display of its alphanumeric information

should be identified by the relevant symbol. If more than one target is selected for

data display, the relevant symbols and the corresponding data should be clearly

identified. There should be a clear indication that the target data is derived from radar

or from AIS.

For each selected tracked radar target, the following data should be presented in

alphanumeric form: source(s) of data, actual range of target, actual bearing of target,

predicted target range at the closest point of approach (CPA), predicted time to CPA

(TCPA), true course of target, true speed of target.

For each selected AIS target the following data should be presented in alphanumeric

form: source of data, ship's identification, navigational status, position where available

and its quality, range, bearing, COG, SOG, CPA and TCPA. Target heading and



reported rate of turn should also be made available. Additional target information

should be provided on request.

If the received AIS information is incomplete, the absent information should be clearly

indicated as "missing" within the target data field.

.5 Effects of sensor errors on ARPA or TT

In compliance with IMO performance standards, automatic tracking accuracy should

be achieved when the tracked target reaches a steady state, assuming the presence

of sensor errors allowed by the relevant performance standards of IMO. Therefore, if

sensor errors are beyond the allowance, the accuracy of ARPA or TT will be affected.

Sensor errors include basic radar errors, THD errors, SDME errors, EPFS errors and

AIS errors. The basic radar error will result in the error of all output data of radar

tracked target. THD heading error, SDME and SDME speed (STW or SOG) error

affects the radar tracked target data, including true course, true speed, true vector,

PADs and other alphanumeric data and graphical data error. AIS error has no effect

on radar tracking data, but the ship's position deviation of EPFS and AIS error may

lead to incorrect association of radar tracked targets with AIS reported targets.

.6 Requirements for THD, SDME, EPFS and AIS inputs

The radar system should be capable of receiving the required input information from:

(1) a gyro-compass or transmitting heading device (THD);

(2) a speed and distance measuring equipment (SDME);

(3) an electronic position-fixing system (EPFS);

(4) an Automatic Identification System (AIS); or other sensors or networks providing

equivalent information acceptable to IMO.

The radar should be interfaced with relevant sensors required by these performance

standards in accordance with recognized international standards.

When the ship is free from shallow water effect and from the effects of wind, current

and tide, errors in the indicated speed should not exceed 2% of the speed of the ship,

or 0.2 knots, whichever is greater.

If the accuracy of SDME is likely to be affected by certain conditions (e.g. sea state

and its effects, water temperature, salinity, sound velocity in water, depth of water

under the keel, heel and trim of ship), details of possible effects may be found in the

equipment manual.

GPS information supplied to radar includes the following:

-A new position should be generated and output at least once every 2 seconds;

-The minimum resolution of position of latitude and longitude should be 0.001

minutes.

The AIS should be capable of receiving information of the other ship automatically and

with the required accuracy and frequency, see Part D 5.2.



IMO performance standards for THD, see R19.

IMO performance standards for SDME, see R8.

IMO performance standards for GPS, see R17.

IMO performance standards for AIS, see R11.

.7 Requirements for association of radar tracked with AIS reported targets

The description in the performance standards about the definition and association

criteria of target association is listed in 5.3.

The user should have the option to change the default condition to the display of

tracked radar targets and should be permitted to select either radar tracking or AIS

alphanumeric data.

For an associated target, if the AIS and radar information become sufficiently different,

the AIS and radar information should be considered as two distinct targets and one

activated AIS target and one tracked radar target should be displayed. No alarm

should be raised.

By showing live radar screenshots, the instructor can better explain how the

presentation of two target symbols for the same physical target leads to data

redundancy.

5.5 Criteria for acquisition of radar targets and activation of AIS targets

.1 Criteria for radar target acquisition and AIS target activation

The acquisition of ARPA or TT target is divided into manual acquisition and automatic

acquisition. In consideration of the advantages and disadvantages of manual and

automatic acquisitions, the officer should make target acquisition plans on the basis of

the navigational needs.

There should be an indication when the capacity of processing/display of AIS targets

is about to be exceeded.

A means to activate a sleeping AIS target and to deactivate an activated AIS target

should be provided. To reduce display clutter, a means to filter the presentation of

sleeping AIS targets should be provided; it should not be possible to remove individual

AIS targets from the display. If zones for the automatic activation of AIS targets are

provided, they should be the same as for radar automatic target acquisition. The

sleeping AIS targets in automatic activation zones may be automatically activated.

Sleeping AIS targets may be manually activated.

The operation to activate/deactivate AIS reported targets are found in relevant part in

Part D, section 6.



.2 Various ways for radar target acquisition

The tracker will record the coordinates of leading edge of the acquired target and

mark an acquisition symbol centred on the position on the screen.

(1) Manual acquisition

The observer moves the cursor onto a concerned target, presses the acquisition

button, and then the screen coordinates of the cursor is recorded as the initial target

position, and acquisition symbol is displayed on the screen. If the target can be

detected in the subsequent acquisition window, the symbol will centre on the leading

edge of the target and follow the movement of the target. The radar initiates target

tracking. According to the radar performance standards, the motion trends of the

target will be given within 1 minute.

(2) Automatic acquisition

When the operator sets a closed acquisition area on the screen, those targets within

or those that intrude the region will trigger the criteria of automatic acquisition. The red

acquisition symbols (see Table 2 2.1 b of Appendix I-7) will flash and an alarm will be

given.

There should be means such as acquisition zones and exclusion zones for the user to

define the boundaries of the auto-acquisition area.

(a) Guard/acquisition zones

The setting of guard/acquisition zones are shown in Fig.5-3. Those targets which are

within the zones and those that intrude the zones from outside will trigger

guard/acquisition criteria. The alarm/acquire zones can be set in various patterns. The

guard/acquisition zones can be set as a variety of graphics area, Fig.5-3 (a) shows

annular guard/acquisition zones, usually up to two guard/acquisition zones. If

necessary, the guard/acquisition zones can be limited by the sectors shown in Fig.5-3

(b). Fig.5-3 (c) depicts an example of an adjustable polygon (irregular)

guard/acquisition zone . Every vertex of the polygon can be adjusted freely.

Fig.5-3 The setting of guard/acquisition zones

(a) Annular zones (b) Annular/sector zones (c) Polygon and exclusion

zones

An exclusion

zone

A guard/acquisition zone



(b) The exclusion zones

Exclusion areas are also known as the restricted zones on radar screen (Fig.5-3 (c)),

where target automatic acquisition is rejected. The purpose of setting exclusion zones

is to prevent the radar automatically acquiring those targets which do not need to be

tracked, including land, islands, clutter and very short-range targets, so as to improve

the purpose of automatic acquisition, to enable better utilization of capacity resources,

and to enhance the readability of information of important targets on screen. Within

the exclusion zones, the officer can also acquire targets manually if necessary.

.3 Criteria for automatic acquisition specified in radar operation manual

Automatic acquisition is supplementary to manual acquisition for open sea with good

weather and sea conditions. Automatic acquisition is not suitable for complicated

situations which require more selectivity. But for any encounter situation, appropriate

settings of automatic acquisition and exclusion zones are recommended. The

automatic acquisition operations are clearly illustrated in the specific equipment

operational manual. The instructor should emphasize that officers who use the

equipment for the first time after a handover on board a new ship should read the

operational manual carefully, and be familiar with the equipment operation

environment.

.4 Criteria for manual acquisition

Manual acquisition is an indispensable function to facilitate collision avoidance and is

suitable for all waters and encounter situations.

In general, for manual acquisition, the officer should follow the criteria of giving priority

to the most concerned targets, i.e. bow, starboard and short-range targets in sight,

and in restricted visibility. There is no particular order among bow, starboard and

short-range targets, and a specific order should take into consideration and be in

accordance with the actual situations at sea. With reference to radar collision

avoidance practice at sea, the priority principles of target acquisition can be illustrated

by using drawings on blackboard, slides, videos, etc.

.5 Target number acquired by ARPA or TT and reported by AIS

In accordance with the requirements in SOLAS, in fulfilment of the radar performance

standards for various sizes/categories of ships/crafts, refer to TABLE 1 of Appendix I-3

for the minimum acquired radar target capacity and activated AIS target capacity.

For the requirements of ARPA acquisition capacity, refer to Appendix I-5 and R5.

.6 Targets that may be cancelled if posing no potential threat

All or one of the tracked targets can be cancelled.

In case of an indication that the target tracking capacity is about to be exceeded, the

operator can cancel targets with no threats manually.

The targets beyond the tracking range may be cancelled automatically.



.7 Tracking results of targets in acquisition, guard and exclusion zones

In guard/acquisition zones defined by the user, the symbols and alarms should be

given when the non-acquired/activated targets are entering the zones or detected

inside the zones. The zones can be applied for radar targets and AIS reported targets

or be set for alarm purpose only, not for acquiring radar target and activating AIS

target. The officer can acquire targets by manual acquisition, or acknowledge (use

ACK button) the alarm of the targets that do not need to be acquired.

In some cases, the automatic acquisition may not be able to obtain the desired results,

such as the automatic acquisition of sea clutter, rain clutter, noise and interference.

Especially, the acquisition of land mass echoes will quickly fill up the available tracking

channels and trigger the target capacity overflow alarm. Therefore, the exclusion

zones are required to be set. False targets (such as clutter) will be captured but may

be lost soon, and the "lost target" alarm can be triggered.

Better teaching effect can be achieved if the instructor uses radar screenshots and

audio/ video aids.


.1 Target tracking

The whole computing process, in which the radar tracks successive position changes

of targets, predicts target motion and obtains motion parameters, is known as target

tracking. For the target tracking function of radar, there are three steps to follow:

(1) Target detection

The process for finding targets under the background of noise and clutter is referred to

as target detection. In order to improve the reliability of automatic target detection, the

officer should carefully adjust the image to optimum. Especially in adverse weather

and rough sea conditions, anti-clutter should be adjusted with prudence to improve

the chances of target detection.

(2) Target acquisition

Target acquisition is a process prior to the process of the tracker recording the initial

position of the target, then starting the detection and tracking of the successive

changes of target positions and finally predicting target motion. The acquisition may

be manual or automatic. For ships less than 10,000 GT, automatic acquisition is an

optional function.

(3) Target tracking

The target tracking process is completed by the tracker automatically. In accordance

with the filtering algorithm, with each antenna scan, the tracker detects the presence

of the target within the tracking window, calculates the target's position, and then

moves the tracking window to predict target motion. The process contains target

acquisition, tracking window setting, tracking window adjusting, target relative motion



trend, and target motion prediction. In this process, the size of the tracking window is

gradually reduced and finally a constant smaller size is maintained. In other words,

the accuracy of target tracking is gradually increased until the tracking is stable. If the

own ship and target ship manoeuvre causes a reduction in accuracy, the above

mentioned tracking process should be restarted.

.2 Lost target and its alarm

(1) Conditions for lost target

The performance standards state that the system should continue to track radar

targets that are clearly distinguishable on the display for 5 out of 10 consecutive scans

or the equivalent. Otherwise, the radar gives target lost alarm.

(2) Causes of target loss

(a) The tracked target is unstable due to sea or rain clutter.

(b) Target echo is too weak.

(c) OS (the own ship) or target manoeuvres rapidly in close range.

(d) The tracked target is obstructed.

(3) Alarm for lost target

(a) There should be a clear indication of the lost target in the operational display area.

(b) There should be an audible alarm which can be switched on and off by the user.

(c) The alarm needs to be acknowledged by the user and stops after

acknowledgement.

.3 Common circumstances leading to "target swap"

(1) Conditions of target swap

During target tracking, if the echoes of two adjacent targets fall into the same tracking

window within continuous antenna scans, the radar may easily give up the tracked

target and turn to track another target. This phenomenon of wrong tracking is known

as target swap.

(2) Causes of target swap

(a) The tracked target is close to unstable strong sea/rain clutter or other interference.

(b) Two or multiple targets navigate extremely closely in dense traffic.

(c) The tracked target is close to large and strong returns.

.4 Effects of "target swap" on displayed data

(1) Anomalies of target vectors

On stabilized radar presentation mode, target swap often causes anomalies of vector.



(2) Target lost

When target swap happens between sparkled clutter and tracked target, a target lost

alarm may be triggered.

(3) Anomalies of target alphanumeric data

After target swap, there are anomalies of target alphanumeric data within the target

data field.

(4) Anomalies of target past positions

After target swap, there are anomalies of target past positions.

5.7 Delays of target tracking processing and AIS reported information

.1 Delay in data display of tracked target

The interval, from the target acquisition, data collection, data processing, automatic

computing to the display of a variety of data and information, is known as radar

processing delay.

According to the radar performance standards, when a target is acquired, the system

should present the trend of the target's motion within 1 minute and the prediction of

the targets' motion within 3 minutes. For most radars, the range and bearing can be

displayed after target acquisition, and CPA is displayed after 30 seconds (1 min

required by the PS), while TCPA, true course and speed are displayed within no more

than 3 minutes. Therefore, target data within 3 minutes after acquisition may be not

accurate enough for use. It is only for reference.

.2 Delay in data display when target ship manoeuvres

The processing delay influences target tracking all the time. Firstly, the collection of

target data is not continuous due to the sweeping period of the radar antenna.

Secondly, the precision and reliability of tracked data can only be achieved by

sufficient detection updates. The motion of tracked target is always regarded as

constant speed and course during the process of target tracking, so processing delay

is required to rebuild stable tracking after a manoeuvre of a target. The more

manoeuvrable the target is, the greater the target deviates from the mathematical

model, and the worse the tracking quality. In other words, the graphical information at

the operational display area and alphanumeric data from the readout window are all

processed data with processing delay. If there is no change of speed and course of

targets, the influence of processing delay to data is small. However, if the target is in

manoeuvring state, the more manoeuvrable the target is, the greater the target

tracked data deviates from real target data and the larger the data deviation.



.3 Possible delay of up to three minutes before full accuracy of derived information attained after acquisition or manoeuvre of a target

Based on the target tracking principle, there will be a processing delay of up to 3

minutes for the tracking process to settle after acquisition or a manoeuvre of the target.

The tracking symbols and alphanumeric data of targets are inaccurate during the

delay period. The more manoeuvrable the target is, the greater the target deviates

from the mathematical model, and the worse the tracking quality.

.4 Delay in data display of AIS dynamic information

(1) Owing to the effect of various interference factors on VDL and the diversity of AIS

equipment, the nominal information reported interval cannot be maintained all the time,

which is beyond the requirements in the AIS protocol.

(2) The information from AIS equipment may not be updated in time as they can

automatically suspend the position reports temporarily when the VDL is busy.

(3) According to the SOTDMA protocol, when time slot resources are constrained, the

information reception of weak AIS reported targets at long-range would be abandoned

automatically.


In consideration of the required performances in Topics 5 and 6 involve

comprehensive and systematic theoretical knowledge and practical ability, it is

impractical to recommend a separate assessment for Topic 5. Therefore, please refer

to assessment techniques in Topic 6.

Teaching guidance

A good understanding of the basic principles of radar automatic tracking systems and

the developmental trend of radar information technology would facilitate the proper

use of the target tracking and AIS reporting functions to acquire proper navigation

information. With the integrated information from the sensors, the radar automatic

target tracking system fulfils the following functions:

manually or automatically acquiring and automatically tracking targets;

obtaining and predicting key collision avoidance parameters of target, which

include range, bearing, speed, course, CPA and TCPA;

automatically appraising the risks of collision and providing a collision avoidance

strategy.

All of these functions contribute to reduce the heavy workload of watchkeeping

officers and improve reliability and efficiency in danger assessment. Fast

developments in satellite positioning, sensor networks, digital communication and



information processing make it possible for modern radar systems to identify targets

automatically with the aid of AIS. A marine radar system has become an

indispensable integrated information platform on a modern bridge.

Based on the navigation information processing platform, the OOW needs no longer

to obtain information from individual sensors, but to set up the radar system based on

the current navigation tasks. Thus, system setting and management should be

highlighted in the course of instructions. A properly instituted system setting is able to

provide optimal navigation information. Conversely, improper setting could mislead

the officer and even lead to close-quarters situations.

Target tracking begins from acquisition. There should be discussions to explore the

advantages and disadvantages of manual versus automatic acquisition, with

emphasis on the importance of manual acquisition. A trainee should develop a

comprehensive understanding of automatic acquisition by setting the guard zones,

acquisition zones and exclusion zones. Additionally, the trainee should be reminded

that even if the automatic acquisition is used, monitoring cannot be neglected.

Moreover, manual acquisition should be used as a supplementary way as appropriate.

Limitations of the information system and the counter-measures should be highlighted

in teaching. Automatic target tracking is based on radar target detection. Echo

fluctuation, clutter and interference would definitely cause some undesired problems

or errors, such as mis-acquisition, mis-tracking, target lost, target swap, etc. The

above-mentioned problems or errors are likely to happen if the working environment

of the radar has any perceptible or imperceptible changes, e.g. clutter and

interference, target blocking, target manoeuvring, and human factors like improper

operation and setting of the equipment, or the failure to keep the radar in an optimal

way to ensure proper automatic target tracking.

One of the difficulties in this topic is how to help the trainees to develop a good

understanding of the "processing delay" in automatic target tracking systems. In

accordance with radar performance standards, the automatic target tracking should

be designed both for processing the target data smoothly and effectively and

detecting a target manoeuvre as early as possible. This data smoothing is referred to

as "processing delay", which is necessary for processing of radar integrated

information during radar automatic target tracking. During this process, by

accumulating the past records of target, filtering sensor errors, and smoothing the

influences of ship movements and sea and weather, the radar is able to predict

speeds and courses, and output the optimal motion data of targets according to given

programmes. "Processing delay" exists not only in a steady state tracking, but also in

the whole tracking process. When the tracked target manoeuvres, the radar system

may not be able to indicate and forecast the manoeuvre in a timely manner. It is why

processing delay happens. Therefore, the automatic tracking function performs well in

stable state tracking when targets and the own ship maintain their courses and

speeds. Vessel rapid manoeuvres affect the accuracy of radar tracking data to a great

extent. In fact, the smoothing process of target information and early detection of a



target manoeuvre is an irreconcilable contradiction that can only be compromised to

some extent.

In this topic, for radar systems satisfying resolution MSC.192(79), Performance

Standards, the key and difficult part lies in the understanding of the relationship

between radar tracked targets and AIS reported targets, especially the association of

radar tracked and AIS reported targets. As a sensor of the radar system, AIS provides

the key information for radar target identification, and contributes to an effective

communication between the own ship and target ships. Meanwhile, AIS also provides

the key data regarding the dynamic and collision avoidance information. AIS is able to

report the targets which the radar fails to detect because of sheltering or poor

reflection with discrimination far better than that of the radar. However, it should be

noted that AIS is not autonomous detection equipment and has no integrity monitoring

information. Therefore, the accuracy of information cannot be determined at the

receiving end. The transmission of dynamic AIS information is subject to the quality of

the communications. The update interval of dynamic information may be longer than

what is required by IMO performance standards, which might lead to major errors in

an irregular communication environment. It should be made aware that AIS can only

be used as an aid for collision avoidance. Thus, for collision avoidance, the focus

should be on the complementary function of AIS for the radar. The association of AIS

reported targets and radar tracked targets are key issues to collision avoidance.

Vector is an important concept in target automatic tracking systems. A good

understanding of vectors is the basis of collision-avoidance. The instructors should,

through presentations and demonstrations, help trainees to learn the related

knowledge of vectors (relative vectors and true vectors), develop an understanding of

vectors' characteristics and applications, and achieve the proficiency of acquiring

navigation information by using vectors in practical operations. Furthermore, the

trainees should be constantly aware of the current vector mode and the risks of using

fixed or improper vector modes. Proper use of the vectors is one of the key elements

for assessing the competency of the trainees.

Theoretically, trial manoeuvre can assist the OOW in making collision avoidance

decisions. However, based on the principles of trial manoeuvre, there are still some

limitations in simulating the dynamic characteristics. Thus the results of trial

manoeuvre can only be taken as a reference rather than a source of information to

rely on fully.

Automatic target tracking performance as specified in IMO radar performance

standards are the minimum requirements. The actual function and performance of

radar equipment should not be below the requirements. It should be noted that the

manufacturers' user manual should be referred to so that the radar can work at its full

capacity and effectiveness.

When designing the lesson plans, instructors are recommended to demonstrate by

simulating real scenarios. As the radar equipment fitted on board is manufactured in

terms of different generations, their performance standards are different as well. The



instructors should prepare the lesson plans in accordance with the requirements of

the competent administration. For example, with respect to the radar equipment

conforming to IMO ARPA performance standards and on the basis of meeting the

KUP tables in the STCW regulations, the instructor can design the lesson plans as per

IMO resolution A. 823(19) and the previous IMO ARPA performance standards,

without coverage of the AIS reporting functions in this topic. If all the topics involved

are to be covered, the lesson plans should follow the related requirements in

resolution MSC.192(79), Performance Standards.



6 Operation of ARPA or radar target tracking (TT) and AIS reporting functions


The major content of this topic covers the operation of ARPA or radar target tracking

(TT) and AIS reporting functions, as well as practical exercises and training sessions

on the target tracking radar/ARPA simulators. This topic focuses on the required

competent performances for the trainees in the application of ARPA or TT radar with

AIS reporting functions.

A good understanding of this topic assists to the trainees in making proper decisions

and taking proper measures for collision avoidance.

Through the study of radar principles, demonstrations and practical training, trainees

should be qualified with the operation of ARPA or radar TT function. They should

know the association method of radar tracked targets with AIS reported targets. They

should understand the factors which influence the accuracy and performance of the

system, and the limitations of radar target tracking. As a navigation aid, over-reliance

on the information provided by radar is unsafe due to possible errors and

misinterpretation of information.


Setting up and maintaining TT or ARPA display is essential to ensure radar target

tracking. Trainees know that proper presentation mode should be used to suit the

actual situation instead of personal preferences.

.1 Adjustment of radar sensors for optimum presentations

Prior to using the function of target tracking, the radar menus and controls should be

adjusted, including the brilliance, gain, manual/automatic tuning, pulse length and

manual or auto clutter suppressions (sea and rain clutter) so that the echoes are

displayed optimally. Except under necessary circumstances, do not use the

correlation, echo average, echo expansion, and automatic clutter suppression. Avoid

using all the anti-clutter controls simultaneously. Refer to 2.1 of Part D for details.

.2 Setting up and confirming of THD and SDME sensors

(1) Setting up own ship's THD

Make sure the gyrocompass readings of the radar or readings from the gyrocompass

repeater are the same with the readings of THD.

Check the data integrity of THD before using it. The method is to check whether the

data are marked as invalid or unavailable by the equipment. Do not use unavailable

data of THD. If the equipment cannot provide integrity monitoring information, the

integrity and validity of heading data should be checked by comparing them with

another THD (if provided).



(2) The setting of own ship's SDME

Make sure the own ship's speed shown on radar is the same with the readings of

SDME.

For collision avoidance, the STW should be adopted. One way of setting STW is by

the speed-log in water-tracking mode and the other is manual speed input. Manual

speed input is used in case of speed-log failure. However, the performance and

function of radar may be affected in this circumstance.

For navigation, SOG should be used. The methods of setting SOG are as follows: log

in bottom-tracking mode, SOG from EPFS, SOG based on a stationary tracked target

as the ground reference and SOG calculated by set and drift which are input manually.

Radar performance may be affected by using the last method.

Check the integrity of the SDME before using it. The method is to check whether the

data are marked as invalid or unavailable data by the equipment. Do not use

unavailable data of SDME. If no integrity monitoring information is provided by the

equipment, the integrity and validity of speed data should be checked by comparing

them with another SDME (if available).

.3 Setting up appropriate presentation modes (motion modes, orientation modes, range scales, past positions, vector modes, PADs)

(1) Motion modes

(a) Relative motion

Relative motion is applicable for collision avoidance in almost all waters.

(b) True motion

Check and confirm THD and SDME first. Refer to 6.1.2 of Part D for details.

True motion with sea stabilization may be applicable in certain situations for

determining target movement, assessing encounter situations and making the right

decisions for collision avoidance. True motion with the ground stabilization is

applicable for navigation in near-coastal waters and narrow channels.

(2) Orientation modes

(a) The azimuth-stabilized orientation mode should be selected, such as N-up or C-up.

Moreover, the azimuth-unstabilized mode should be avoided as much as possible.

For modern radar, the TT function is often prohibited when the azimuth-unstabilized

mode is selected.

(b) In order to identify the target, it is better to select N-UP mode for position-fixing and

navigation by radar with paper chart, when the ship is engaged in coastal navigation.

(c) It is better to select C-up mode for the ship altering course or yawing, when the

ship is navigating in harbour waters or narrow channels.

(d) C-up is convenient for position-fixing and navigation by radar with ECDIS.

(e) Unstabilized H-up presentation should be avoided. For modern radars, the target

tracking function is usually prohibited under the H-up mode.



(3) Range scales

In accordance with the IMO radar performance standards, the range scales for target

tracking include at least 3, 6 and 12 nm; most modern radars are from 0.75 to 48 nm.

As per Performance Standards, ARPA tracking range should exptend to a minimum of

12 nm. Training provider should be made aware that certain radars may not be able to

track targets beyond 12 nm range.

Range scales should be switched at frequent intervals during a voyage to optimize the

presentation of information adapting to the current encounter situations, and the OOW

must perform long range sccaning to detect targets in the vicinity well in advance. The

12 nm range scale is recommended for acquiring and tracking the targets to provide

officers with the opportunity to take control of the overall situation, and allowing them

to take actions to avoid collision risks in ample time. The use of shorter range scales

is preferred when engaged in narrow passages.

(4) Past positions

There are two kinds of past position modes. One is true past position mode and the

other is relative past position mode. It is recommended that the appropriate past

position mode according to the actual purpose be selected. Refer to 6.3.3 of Part D for

details.

(5) Vector modes

There are two kinds of vectors. One is relative vector and the other is true vector.

Refer to 6.3 of Part D for details.

(a) Use relative vector to obtain CPA/TCPA and make a collision risks assessment.

(b) Use true vector to assess encounter situations and make decisions for collision

avoidance.

(c) Select the appropriate vector mode at any time when it is necessary, taking into

consideration the present encounter situations and collision risks.

(d) In collision avoidance with a single target ship, the true vector (with properly

adjusted time) can be used to manage collision risk assessment, collision avoidance

decision and actions to be taken at the same time.

(6) PADs (where applicable)

The trainees may refer to 5.1.4 of Part D for the concept of PADs and 6.3.4 of Part D

for interpretation of PADs information. PADs are applicable for open seas. The

instructor should emphasize that it is inappropriate to use PADs in crowded waters

with multiple targets, such as harbour waters and narrow channels, etc.

.4 Setting up CPA LIM/TCPA LIM (limit)

The safety limitations of CPA LIM/TCPA LIM should be adapted to the present

navigation situation but not the officer's personal preference. Many factors should be

considered while setting the CPA LIM and TCPA LIM, including the own ship's



tonnage and manoeuvrability, the effectiveness of the bridge team, the proximity of

confined waters and traffic density, sea state and weather conditions.

.5 Manual target acquisition

Refer to 5.5.2 of Part D for the criteria of manual acquisition. For navigation in

crowded waters, the true trail function is helpful to distinguish moving targets from

stationary targets, and to identify the encounter situations, and hence to acquire the

critical targets according to the manual acquisition criteria.

.6 Setting up automatic guard/acquisition and exclusion zones

Automatic acquisition function is realized by setting up automatic guard/acquisition

and exclusion zones (Refer to 5.5.2 Part D).

Generally, it is recommended that guard zones can be set at ranges of 8 to 12 nm,

acquisition zones at 6 nm, and ranges of less than 1.5 nm should be set as the

exclusion zones. In addition, according to the situation of the navigational waters,

comprehensive and reasonable setting of guard/acquisition and exclusion zones by

circle, sector or polygon can be considered.

The setting of exclusion zones may avoid spurious interference and prevent targets

from being acquired, e.g. land, islands, clutter, and others which need not be tracked

by radar.


According to resolution MSC.192(79), Performance Standards, AIS is one of the

required sensors of the radar. The trainees should have full understanding of setting

up and maintaining AIS reported target displays.

.1 Setting up and verification of EPFS sensor

The accuracy of AIS reported targets is related to the accuracy of the own ship's

EPFS, the accuracy of targets' sensors, and the situation of AIS VHF data link (VDL).

The OOW should check and confirm the accuracy and integrity of the own ship's

EPFS, communicate with the target ship in an active and effective manner, and verify

the reliability of the target ships' AIS information.

.2 Setting up and verification of THD sensor

Refer to 6.1 of Part D for setting up THD sensors. In the absence of THD signals, AIS

reported target information will not be displayed on the radar.

.3 Setting up and verification of SDME sensors

Refer to 6.1 for setting up SDME sensors. Although the speed of the own ship can be

input manually, the display of AIS reported target on the radar may be affected.

According to IEC 62388 radar performance standards, AIS reported targets will be

displayed as CTW and STW when the speed sensor mode is sea stabilized. AIS

reported targets will be displayed as COG and SOG when the radar speed sensor is

in the ground stabilized mode.



.4 Setting up AIS presentation modes (sleeping targets, activated targets, selected targets, vector, past positions, sea stabilized and ground stabilized)

The function of AIS reported target facilitates radar tracking. It should be regarded as

a matter of principle that no interference with radar information should be caused

when setting the display modes of the AIS reported function. Full use should be made

of all the AIS display modes for optimal effect in a particular environment. Refer to

Table 2 of Appendix I-7 for AIS reported target symbols displayed on the radar.

(1) Filtering of AIS sleeping targets

According to IMO MSC. 192(79) 5.26.3, to reduce display clutter, a means to filter the

presentation of sleeping AIS targets can be set by criteria (e.g. by target range,

CPA/TCPA or AIS target class A/B, etc.).

The criteria for filtering of sleeping targets may vary with different manufacturers. It

can be done by setting up the filter status based on the target's range, CPA/TCPA or

target class (class A, B) or by controlled zones. For the former, filtering by target class

(A or B) requires great care when in use. More modern radars only allow filtering by

class when combined with one or more other factors, for example, CPA/TCPA, range.

Older radars may also allow such a combination with Class A or B filtering. For the

latter, the targets located inside the zones are activated AIS targets and the others

located outside the zones are sleeping targets.

(2) Activation of AIS targets

(a) Automatic activation of AIS targets

There are two basic methods to activate the targets. The first one is setting up the

filter status by the user, e.g. target range, CPA/TCPA and target class (class A, B).

The other is setting up the controlled zones. Resolution MSC.192(79), Performance

Standards has specified that if zones for the automatic activation of the AIS targets

are provided, they should be the same for radar automatic target acquisition (see

5.26.4 in resolution MSC.192(79), Performance Standards). For radar automatic

target acquisition, refer to 6.1.6 of Part D.

(b) Manual activation of AIS targets

Move cursor and click the selected AIS targets.

(3) Deactivation of activated targets as sleeping targets

The operation of deactivating AIS activated targets as sleeping targets varies from

different manufacturers. Refer to the manufacturer's operation manual for details.

(4) Selection of AIS targets

Move the cursor and select any AIS activated targets. The target will present

information in alphanumeric and graphical form. Refer to Table 2 of Appendix I-7 for

details.



(5) Selection of vector modes

The vector of AIS activated target is used to predict the movement of the target. The

setting of vector length for AIS targets is the same as radar tracked target.

(6) Setting of AIS past positions

The time interval between past positions of an AIS activated target is equal to that of

radar tracked targets.

(7) Setting of sea stabilized mode and ground stabilized mode

The motion mode of AIS reported targets is the same as that of tracked targets.

Where sea stabilization mode is selected, the CTW and STW are presented in place

of COG and SOG (refer to 5.28.3 in resolution MSC.192(79), Performance

Standards).

6.3 Operation of ARPA or TT and AIS functions to obtain target information

The trainees should be able to operate ARPA or TT and AIS functions to obtain target

information properly after they are familiar with the setting up of these functions. The

target information of ARPA or TT and AIS is obtained from two mutually independent

sensors. The trainees should develop the skills of associating radar tracked targets

with AIS reported targets.

.1 Obtaining information from relative and true vectors in both relative and true motion presentation modes

Refer to 2.9 of Part D for the concept, features and operation of relative motion and

true motion presentation modes. Operate to display the relative vector and true vector

in various motion modes respectively.

(1) Relative vector

Refer to 5.1.1 of Part D for the concept and features of the relative vector.

Operate the relative vector to obtain relative course and speed of target. Based on the

set time and the length of the relative vector, the OOW can determine the

approaching speed of targets in a short time.

Adjust length of relative vector to obtain CPA and TCPA of target. As shown in Fig.5-1

(a) and (b), the perpendicular line segment from the own ship to relative vector of

target or its extension line is called CPA; the target navigation time from the start point

of the target relative vector to the foot of CPA is TCPA. By adjusting the vector time,

the operator can estimate the target CPA and TCPA directly from the screen within a

short time, and compare them with the CPA LIM and TCPA LIM so as to assess

collision risks.

By operating the relative vector, the operator can determine whether there are risks of

collision with multiple target ships. The operation procedures include the following

steps: draw a CPA LIM circle on the display by using VRM. The centre of the circle is



CCRP and the radius is CPA LIM. If the relative vector of the target or its extension

line intersects with the CPA LIM circle, a risk of collision exists, as T3 shown in Fig.5-1

(a) and (b). However, if the relative vector of the target or its extension line is far from

the CPA LIM circle, it is a safe target, as T1 shown in Fig.5-1 (a) and (b). To facilitate

the observations, the length of the vector should be adjusted as required.

(2) True vector

Refer to 5.1.1 of Part D for the concept and features of the true vector. When SOG is

selected in the radar, the true vector is the vector relative to the ground. When STW is

selected, the true vector is the vector relative to the water.

(a) Through operating true vector, true speed of the target ship can be obtained

according to the length of the vector.

(b) Under the true vector mode, the officer can visually assess the encounter

situations between the own ship and the target ships, as well as that among the target

ships, ascertain the responsibilities and obligations in the situation, and make collision

avoidance decisions according to the encounter situations and the COLREGs. As

shown in Fig.5-1 (c) and (d), the own ship and the target T1 constitute a crossing

situation, in which the own ship is the stand-on ship and T1 is the give-way ship; the

own ship and T2 are in the same course and speed, and do not affect each other; the

own ship and the target T3 constitute a crossing situation, in which the own ship is the

give-way ship; T3 is the stand-on ship and T4 is a fixed target.

(c) Collision risks can be assessed by operating the true vector, namely, adjust the

vector time continuously, change the vector length, and then observe the tail end of

the true vector between the own ship and the target ship. If the minimum range

between the tail end of the own ship's vector and target vector is less than CPA LIM,

then a risk of collision between the own ship and the target ship exists. The area close

to the vector tail end is the possible collision waters.

(d) In an overtaking situation, the process of overtaking can be shown directly by

continuously adjusting the length of the true vector, so as to estimate the time and

water areas of overtaking. This can be used as reference for ships manoeuvring in

bends and narrow channels, especially for ships entering the areas where overtaking

is prohibited.

(e) The true vector of the own ship can help the ship to berth in poor visibility in the

best way.

(f) OOW should be aware that the changing over from sea stabilized mode to ground

stabilized mode or vice versa, there is a processing delay up to 3 minutes (as per

Performance Standards) during which period, the true vector information may be

unreliable.

.2 Importance of switching between true and relative vectors

On the basis of an understanding of the concept of relative vector and true vector, the

encounter situations and the risks of collision are assessed by using vector. For this

purpose, the relative vector is used in the stage of assessing collision risks, and the



true vector is used in the stage of collision avoidance decision-making. In taking

action to avoid collision, the two types of vectors could be switched over when

necessary giving consideration to both the encounter situations and the assessment

of risks.

(1) Application of relative vector

(a) By operating relative vectors, the risks of collision with multiple target ships can be

determined simultaneously within a short time.

(b) In the case of the own ship manoeuvring, the relative vector cannot be used to

determine the manoeuvring state of the target, so it is not applicable for evaluating

risks of collision.

(2) Application of true vector

(a) In making collision avoidance decisions, the encounter situations between the own

ship and target ships may be assessed directly by the true vector, and then collision

avoidance actions will be taken according to the encounter situations and the

COLREGs.

(b) The true vector relative to water is applicable for ship collision avoidance. The true

vector relative to the ground is applicable for collision avoidance giving consideration

to both navigation in coastal waters and narrow channels.

(3) Switching between relative and true vectors

Relative vectors are helpful to assess the risks of collision, and true vectors are

helpful to make collision avoidance decisions. It is noted that vector modes should be

switched over when appropriate.

.3 Obtaining information from past positions

(1) Past position mode

There are true past position and relative past position modes. For old types of radars,

past position modes are consistent with radar motion modes, i.e. true past positions

are displayed on true motion presentation mode, and relative past positions on

relative motion presentation mode. However, past position modes are always

consistent with vector modes for the latest radars, i.e. true past positions are

displayed under the true vector mode, while relative past positions are displayed

under the relative vector mode.

(2) Application of past position function

(a) Selection of past position function

In case of the own ship keeping the present speed and course, the relative past

position function facilitates in estimating the target motion relative to the own ship and

the target manoeuvring situation over a past period of time. The function of true past

positions stabilized relative to the water is helpful to assess the target navigation

status in collision avoidance. While the function of true past positions stabilized to the

ground is useful for position monitoring in navigation.



(b) Application in collision avoidance

When the function of target true past positions relative to the water is not on a straight

line, it indicates that the target has altered course. When the intervals of the adjacent

past positions increase or decrease, it indicates that the target has speeded up or

slowed down. The function of true past positions relative to the water is shown in

Fig.6-1. The own ship "O" keeps the speed and turns to starboard (equal spaced past

positions relative to water in a curved line); target T1 keeps the course and speed

(equal spaced past positions relative to water in a

straight line); target T2 keeps the course with speed

increasing (beginning with intensive then sparse past

positions relative to water in a straight line); target T3

keeps the speed with turning to starboard (equal

spaced past positions relative to water in a curved

line); target T4 is floating on the water (no past

positions and true vector).

(c) Verification for radar tracking performance

Under the conditions that the own ship keeps the

present speed and course, when past positions of all targets are not presented in

proper order, there may be problems in the process of target tracking which results in

the presentation of unreliable tracking data.

.4 PADs

PADs is an acronym for "Predicted Areas of Danger", which are the possible collision

areas of the own ship with the target under the condition of the target keeping the

speed and course and the own ship keeping the speed. The size of PADs is in

connection with the target's relative position, target's speed and course, the own

ship's speed and CPA LIM. If the heading line of the own ship intersects with the

target's PADs, the own ship and the target have a risk of collision, as shown by target

T2 in Fig.5-2 (refer to 5.1.4). If the heading line of the own ship does not intersect with

the PADs of the target, the own ship and the target have no risk of collision, as shown

by the target T1 in Fig.5-2.

Cautions to use PADs:

(1) When switching to PADs mode, only the true vectors will be displayed. The range

between target and the centre of a PAD is not the true vector of target.

(2) When STW is selected, PADs will indicate safety course; when SOG, is selected,

PADs will indicate safety course over ground.

(3) The PADs can be used for the prediction of collision risks between the own ship

and targets only; not for the situations among target ships.

(4) In the case of multiple targets and PADs, complex graphics will be involved. As a

result, PADs are not applicable for narrow channels, fishing areas and the waters with

frequently manoeuvred targets.

O

T3

T2

Fig.6-1 TM/TV past positions

T4

T1

T5



(5) The functions of PADs are neither a compulsory requirement in radar Performance

Standards, nor available on most radars currently.

.5 AIS reported Information

(1) AIS reported targets

AIS reported targets provide graphical and alphanumeric display modes:

(a) AIS reported target graphical presentation

Graphical display presents AIS target types (sleeping, activated, selected, dangerous,

lost and true scaled outline), the position to the own ship, and to indicate the course

and speed of the AIS target by predicted vector. The comparison between AIS target

and radar targets is shown in Table 6-1. The instructor should emphasize the features

of AIS targets and their differences with tracked targets.

Tab.6-1 Reported AIS target symbols and tracked radar target symbol

Reported AIS target Tracked radar target

Target type Symbol Target type Symbol

Sleeping

Radar target Echo paint

Activated

Tracked

Selected

Selected

Dangerous

Dangerous 18

Lost

Lost



True scaled

outlines

True scaled

outline

(b) AIS reported target alphanumeric display

The following data should be presented in alphanumeric form: Source of data, the

ship's identification, (MMSI), navigational status, position where available and its

quality, range, bearing, COG, SOG, CPA and TCPA, target heading, turning rate, and

other requested information. Where sea stabilization is selected, the CTW and STW

should be presented in place of COG and SOG. If the received AIS information is

incomplete, the absent information should be clearly indicated as "missing" within the

target data field. The data should be displayed and continually updated, until another

target is selected for data display or until the window is closed.

(2) The application of AIS reported target on radar

(a) Setting up AIS reported target

Refer to 6.2 of Part D for setting and maintaining normal AIS reported target display.

(b) Association of radar tracked with AIS reported targets

Refer to 6.3.6 of Part D for association of radar tracked with AIS reported targets.

(c) Setting up AIS reported target alarm

Refer to 6.3.10 of Part D for setting up AIS alarm.

.6 Association of radar tracked targets with AIS reported targets

Refer to 5.3 of Part D for the association concept and criteria of radar tracked targets

with AIS reported targets.

(1) Principles of TT and AIS targets association

The accuracy of AIS reported target is greater than that of radar TT, especially in the

frequently used ranges (3, 6 and 12 nm). Taking AIS information as reference is the

basic principle of association when the system accuracy meets the relevant

requirements.

When the range scale is less than 1.5 nm, and the system accuracy meets the

relevant requirements, the accuracies of radar TT and AIS system are equivalent. In

this condition, either the AIS reported targets or the radar tracked targets can be set

as the default association condition for the purpose of safe navigation.

In case of doubt about the accuracy of AIS reported information, or when the GNSS

deviation of the own ship is large, i.e. the positions of TT and AIS targets have more

deviations, the operator should set the tracked target as default association condition.

(2) Methods of setting up association criteria

Refer to 5.3 and 5.4.7 of Part D for the methods of setting up association criteria.



.7 Assessment of encounter situations and collision risks by associated information

The encounter situations and collision risks will be assessed after associating radar

tracked with AIS reported targets. Described below are the methods used to identify

the dangerous targets.

(1) Data comparison

Officers are required to confirm and compare the tracked target's CPA/TCPA with the

set CPA FUTURE/ KATCH UP LIM, so as to evaluate the encounter situations and

assess collision risks as early as possible. Details are as follows:

(a) CPA＞CPA LIM, non-dangerous target;

(b) CPA≤CPA LIM, TCPA>CPA LIM, non-imminently dangerous target, the officers in

charge of navigation should pay attention to the change of TCPA;

(c) CPA≤CPA LIM, TCPA≤TCPA LIM, imminent dangerous target exists. The radar will

give sound and visual alarms to draw attention. Collision avoidance measures should

be taken at once.

(2) Vectors

Vectors can be used to evaluate the risks of collision in a short time, which is essential

for trainees to use. The primary operation in using this method is switching over

between true vector and relative vector with the aid of the circle of CPA LIM when

appropriate. The relative vector is useful to determine the risks of collision; the true

vector is to assist decision making in collision avoidance. Switching over between

relative and true vector is recommended in collision avoidance actions. Details have

been discussed in Sub-topic 6.3.2 of Part D.

(3) PADs(where appricable)

Refer to section 6.3for details.

The training institutions with equipment meeting the recommendations annexed to

resolutions A. 422(XI) and A. 823(19) only, may skip the parts concerning association

operations.

.8 Trial manoeuvre

(1) Operation of trial manoeuvre

The functions of trial manoeuvre with the simulated time to manoeuvre and the own

ships' dynamic characteristics vary with different radar by different manufacturers. The

radar operation manual should be referred to for detailed operations. The basic

operation procedures are listed below:

(a) Before starting the trial manoeuvre, the own ship's turning rate, turning radius and

the rate of speed change should be input in advance.

(b) The own ship's new heading and/or new speed should also be input beforehand.

(c) Set the simulated time to manoeuvre in advance.



The operation of trial manoeuvre with simulated time to manoeuvre and the own

ship's dynamic characteristics can be divided into three stages. First, the own ship

proceeds with current heading and the speed within the delay. Second, the own ship's

dynamic characteristics will be simulated. Finally, new course and/or speed will be

simulated.

According to the manoeuvre plan, the trial manoeuvre can be divided into heading trial

manoeuvre, speed trial manoeuvre and the mixed trial manoeuvre. In collision

avoidance practice, course alteration trial manoeuvre is usually used instead of

others.

Operation of trial manoeuvre without simulated time to manoeuvre and the own ship's

dynamic characteristics is a relatively simple trial manoeuvre which is used for old

ARPAs. This kind of trial manoeuvre is similar to the third stage of modern radar trial

manoeuvre as mentioned above. As an example, the third stage simulation of trial

manoeuvre is illustrated here with the heading trial manoeuvre. The operations of

other two trial manoeuvres are similar to this example in principle.

(a) Trial manoeuvre based on data comparison

Comparing the CPA/TCPA of the target with CPA LIM/TCPA LIM is one of the most

accurate methods for trial manoeuvre. Altering the own ship's trial heading gradually

until the alarm is cleared. The simulated heading obtained at that time is the safe

borderline heading.

(b) Vector mode trial manoeuvre

Due to the fact that vectors enable immediate assessment of collision risks and visual

grasp of the encounter situations, the trial manoeuvre in vector mode applies to all

navigation situations. The detailed operation is as follows:



Firstly, assess the risks of collision in the mode of relative vector, as shown in

Fig.6-2(a), the relative vector line of target T2 intersects with the CPA LIM circle, then

collision risk is determined.

Then, switch to true vector mode, as shown in Fig.6-2(b), the own ship is the give-way

ship according to the COLREGs and should take collision avoidance measures.

Next, start trial manoeuvre function. A letter "T" will appear below in the operational

display area. Under the relative vector mode and taking consideration of the

COLREGs, a safe limitation course 050 is obtained, which is shown in Fig.6-2 (c).

Finally, switch to true vector mode (see Fig.6-2 (d)), to verify the effect. Meanwhile, as

a secondary reference, verify that all the true vector target arrow ends are away from

the vector tail end of the own ship, which means the alarm is cleared successfully.

(c) Trial manoeuvre in PADs mode

As the safe heading can be obtained by operating the EBL in PADs mode, the heading

trial manoeuvre is not necessary. Speed trial manoeuvre can be used for collision

avoidance by changing speed. In this case, the trial manoeuvre speed should be

entered, and the own ship's heading should not intersect with PADs.

(2) Checking validity of intended course alteration and speed change

The operation of checking intended alteration of course and speed with trial

manoeuvre facility is as follows:



Start trial manoeuvre and trial manoeuvre course and speed as intended course and

speed.

Verify the safety of the own ship on the new course and speed by the method

aforementioned.

If there is no dangerous alarm, the alteration of the course and speed is valid.

The trial manoeuvre can also be used by the own ship to predict the proper timing for

resuming the course and speed after collision avoidance.

.9 Setting up and acknowledgement of target tracking operational alarms (target capacity overflow, dangerous target, new target entry, lost target)

(1) Target capacity overflow alarm

Refer to 5.5.5 of Part D for the capacity of radar acquired targets. There will be an

indication when the target tracking capacity is about to be exceeded by the system

capacity. In this circumstance, the less significant targets should be cancelled so as to

keep enough capacity.

(2) Dangerous target alarm

When the calculated CPA/TCPA of a tracked target is less than the CPA LIM/TCPA

LIM, the dangerous target alarm should be activated. The alarm should be

acknowledged and trial manoeuvre should be considered to be making the decision

for collision avoidance.

(3) New target entry alarm

Set up guard rings or guard zones. When targets enter or are within the zones, new

target entry alarms will be activated. Officers should acknowledge the alarms and then

decide whether or not to acquire the targets according to the situation. For the guard

rings or guard zones which are set up with automatic acquisition function, the targets

within or entering the zones will be acquired automatically.

(4) Lost target alarm

Lost target alarm is very likely to be activated when the target or the own ship is

changing course or speed suddenly. In this circumstance, the alarm should be

acknowledged, and the decision whether or not to acquire the target again should be

made.

.10 Setting up and acknowledgement of AIS operational alarms (target capacity overflow, dangerous target, lost target)

(1) AIS target capacity overflow alarm

According to the SOLAS Convention and resolution MSC.192(79), Performance

Standards, the minimum capacities of activated and sleeping AIS targets for various

sizes/categories of ship/craft are listed in TABLE 2 of Appendix I-3.

Reminder messages are available when the capacity of AIS reported targets is about

to be exceeded. The AIS target presentation status (activated or sleeping) can be

switched over. To reduce display clutter, means to filter the presentation of all or part



of sleeping AIS targets should be provided by setting up the relevant filter status (e.g.

target range, CPA/TCPA or AIS target class A/B). In this regard, please refer to 6.2.6

of Part D.

(2) Dangerous target alarm

The AIS dangerous target alarm is the same as that of the radar. In other words, if the

calculated CPA/TCPA of a tracked target or an activated AIS target is less than the

CPA LIM/TCPA LIM, a CPA/TCPA alarm will be activated.

The instructor should emphasize that the pre-set CPA LIM/TCPA LIM applied to

targets from radar and from AIS should be identical. As a default state, the CPA/TCPA

alarm functionality should be applied to all activated targets. On user's request, the

CPA/TCPA alarm functionality may also be applied to sleeping targets.

(3) Lost targets alarm

It should be possible to enable or disable the lost target alarm function for AIS targets.

A clear indication should be given when the lost target alarm is disabled.


The AIS lost target alarm function is enabled. The target is of interest, according to

lost target filter criteria. A message is not received for a set time, depending on the

nominal reporting rate of the AIS target. Then:

The last known position should be clearly indicated as a lost target and an alarm be

given. The indication of the lost target should disappear if the signal is received again,

or after the alarm has been acknowledged. A means of recovering limited historical

data from previous reports should be provided.


The trainees should be made aware that errors are not inherent in the radar system,

but result from misunderstanding, inexperience or careless observation. The most

common misunderstandings are as follows:

.1 Possible errors due to improper sensors' setting and/or adjustment

(1) Improper THD setting

Improper THD setting reduces the data accuracy from TT. The radar stops target

tracking functions without THD and can switch automatically to the unstabilized head

up and relative motion mode.

(2) Improper SDME setting

Improper SDME setting reduces the data accuracy from TT. The radar stops target

tracking functions without SDME. Misuse of STW or SOG may cause wrong

information output for collision avoidance and produce potential risks.

(3) Improper EPFS setting



Improper EPFS setting results in incorrect association of radar tracked targets with

AIS reported targets.

(4) Improper AIS setting

Improper AIS setting results in incorrect association of radar tracked targets with AIS

reported targets.

(5) Improper radar setting

The Incorrect setting reduces the detecting ability of the radar, and weak target

echoes are likely to disappear. The radar errors due to improper adjustment of the

picture will degrade the accuracy of TT. Refer to 6.1 of Part D for details.

.2 Inconsistent information deriving from alphanumeric data vs. vectors

In relative vector operation, the target speed from graphical display is relative speed,

while the speed from digital display is true speed.

.3 Possible errors due to misinterpretations of radar presentation and vector modes

(1) Relative vector and true vector are important functions of TT/ARPA. Confusion of

relative vector and true vector may lead to misinterpretation of encounter situations

and taking incorrect actions, which might lead to close-quarters situations or even an

accident.

(2) The display features of combined modes should be understood such as the

combination of relative motion and relative vector, true motion and true vector, relative

motion and true vector, true motion and relative vector. Misunderstanding or

confusion of display features may affect the proper use of radar.

(3) It is wrong to determine CPA and TCPA by forward extrapolation of true vector as

this will result in wrong assessment of dangerous targets and even wrong actions to

take.

.4 Possible errors due to misinterpretations of own ship's speed

Improper speed input may result in errors in the collision avoidance or navigation, and

affect the safety of navigation.

In most situations, radars are mainly used for collision avoidance. The influence of

currents is regarded as identical for all the ships in the waters, so STW (speed log

input or manual input) is needed. However, information from radar may be unreliable if

the complex currents have a notably different influence on the own ship and targets in

narrow channels. This will result in wrong evaluation of a collision situation.

In coastal or narrow channel waters, especially in waters largely affected by currents,

SOG is preferred for ground stabilization.

.5 Possible errors due to misinterpretations of trial manoeuvres

The trial manoeuvre is a computer simulation of the own ship's manoeuvre. A safety

margin should be considered when setting up the parameters of a trail manoeuvre,

because there are large deviations between the actual movement of the ship and the



simulated movement. Issues to consider during a trial manoeuvre operation are as

follows:

(a) Functions of trial manoeuvres are neither applicable to evaluate whether the trial

manoeuvre plan by the officers conforms to the COLREGs, nor to replace their

valuable sea experience.

(b) During the trial manoeuvre, new risks of collision with other non-tracked targets

may occur.

(c) During the trial manoeuvre, the operational display area presents a simulated

image. Alphanumeric data presentation is needed to monitor actual encounter

situations.

(d) Issues that should be considered when setting up the simulated time to

manoeuvre include the officer's seamanship and navigation experience, helmsman

proficiency, settings of CPA LIM/TCPA LIM, ship's size, ship's manoeuvre ability,

encounter situation, and manoeuvring plan.

(e) In the use of the trial manoeuvre function for decision making, sufficient safety

margins should be taken into account regarding the errors of radar tracked and AIS

reported targets.

(f) The outcomes of a trial manoeuvre are effective only under the premise that there

are no manoeuvring operations for both the own ship and the target ship. If the own

ship or the target ship manoeuvres during the trial manoeuvre, the trial manoeuvre

should be terminated at once. New decisions should not be made until both ships'

courses and speeds stabilize again.

.6 Reacquired "lost target" may present false course alteration and speed change

When a lost target is re-acquired, the system should present the trend of the target's

motion and its initial tracking data within 1 minute. The prediction of the target's

motion and stable data and vector of target should be presented in 3 minutes.

Misunderstanding of data processing delay may lead to misinterpretation of radar

presentations and data of the tracked target. It may result in close-quarters situations

if unstable tracked data is used.

.7 PADs not indicating mutual threats between targets

PADs are the possible collision areas based on the condition of the target keeping the

speed and course and the own ship keeping the speed. Therefore PADs information

apply only to the own ship and targets, and do not indicate mutual threats between

targets.

.8 Length of lines from target to PAD not indicating target speeds

A line between the target and PADs indicates the relationship between the own ship

and the target only. The length of the line is not an indicator of the target's speed.

.9 Past position presentation not necessarily in the same mode as vector



It is propitious to assess the encounter situations when past position modes are

consistent with the vector modes, i.e. relative past positions are displayed under the

relative vector mode and true past positions are displayed under the true vector mode.

However, for early age of ARPAs, past position modes were consistent with radar

motion modes. In this case, relative past positions might be combined with true

vectors, and true past positions with relative vectors. The trainees should understand

that the past positions may not be in the same mode as the vector.

.10 Direction change of relative past positions not necessarily indicating a target manoeuvre

When relative vector mode is used to display relative past positions, the change of the

own ship's course and speed may result in a change of the relative past positions of

the target, so the change in the past positions does not imply that the target is

manoeuvring. Refer to 6.3.3 of Part D for details.

.11 Misinterpretations of ARPA or TT and AIS information may lead to false assessment of situations

(1) Incorrect interpretations of data from target tracking may lead to

misunderstandings of true course and true speed, CPA, TCPA, and the relative speed

and course of a target. As a result a dangerous target might be taken as a safe one,

which would cause potential threats to safe navigation. Similarly, misinterpreting might

result in mistaking a safe target for a dangerous one, which would cause unnecessary

tension and even inappropriate actions.

(2) Misinterpretations of AIS data update interval may result in misunderstandings of

the target motion, especially in harbour waters, narrow channels and other congested

areas with crowded AIS equipment, which causes the update interval of AIS

information to exceed the required time as per the AIS protocol. In this case, AIS

reported target information does not reflect the actual movement of the target. It is

dangerous to evaluate the risks by scanty information merely depending on AIS, as

the results may bring about close-quarters situations.


.1 Effects of radar sensor errors on displayed data

Errors caused by the radar sensor include range and bearing measurement errors.

Refer to 1.4.3 of Part D for details. Radar range and bearing measurement errors

affect the data accuracy of targets' relative motion data and true motion data, including

relative speed, CPA, TCPA, relative vector, target true speed and true vector.

.2 Effects of heading error on displayed data



The own ship's heading error affects the calculation of true course and true speed of

radar tracking targets, which will result in the errors of target's "true" data, including

true course, true speed, true vector, PAD, and the corresponding alphanumerical data

and graphical data. Instructors may discuss it using the velocity vector triangle as

shown in Fig.6-3, where the heading error of θ is wrongly indicated as TA' vector,

rather than the correct vector TA.

.3 Effects of speed errors on displayed data

The own ship's speed error affects the calculation of true course and true speed of

radar tracking targets, which will also result in the errors of target's "true" data,

including true course, true speed, true vector, PAD, and the corresponding

alphanumeric data and graphical data. Instructors may discuss it using velocity vector

triangle as shown in Fig.6-4, where the speed error of –ΔV is wrongly indicated as TA'

vector, rather than the correct vector TA. This may mislead the officer to make the

same wrong collision avoidance decision as described with gyrocompass error.

.4 Unreliable tracking data when manoeuvring of own ship or target ship

Topic 5 describes the basic principles of radar target tracking and outlines the

processing delays. The displayed data is unreliable when the target is initially tracked

or when the own ship or the target ship has just altered its course or speed. Refer to

5.5 of Part D and 5.6 of Part D for details.

.5 Satisfactory target tracking performance as indicated by smoothness of past positions

Correct understanding of information from radar past positions is described in 6.3.4 of

Part D. The function can be used to check the reliability of ARPA or TT data.

(1) On the basis of stable and continuous tracking, under the preconditions that the

own ship keeps the speed and course, the tracker may have some problems if past

positions of all targets have irregular or unstable presentations.

(2) The past position function can also be used to test radar tracking performance in

response to the own ship's manoeuvres. If manoeuvres of the observing or a target

ship result in tracked target lost, the manoeuvre parameters at that moment represent

the limitation to maintain a normal tracking. In this circumstance, the record of past

E

E' O CPA

A

SHM

F

θ

E

A' B

T

Fig.6-3 The impact of heading

errors

-ΔV

O

SHM

F CPA

E'

A

A'

B

T

Fig.6-4 The impact of speed error



positions can visually indicate the limitation of target tracking in manoeuvre

conditions.

.6 Causes of data errors of AIS reported target

AIS reported targets and relative functions are described in 5.2 of Part D. Errors of the

displayed data arise possibly from the following factors:

(1) Uncertainty of the accuracy of ship's position by AIS

The core of AIS is the GNSS. The accuracy of AIS may decline due to the declining

accuracy of the GNSS. The accuracy of the GNSS is related to the system,

environment, or other factors. Refer to IMO Model Course 1.34 for details.

(2) The lack of integrity indication of AIS data

At the receiving end, the operator cannot verify the accuracy and integrity of data from

the sensors of the target. So the accuracy of AIS reported data is difficult to be

determined.

(3) Limitation of AIS dynamic data updating interval by the AIS principle

and VHF Data Link (VDL)

The updating interval of AIS dynamic data is influenced by the ship's manoeuvreability,

normally from 2 seconds to 3 minutes. Meanwhile, owing to VDL affected by various

interference factors and the diversity of AIS equipment, the nominal information

reported interval often cannot be maintained.

(4) Improper setting for AIS reported information

The irregular setting possibly involves improper setting of GNSS antenna location,

static information. This will result in data errors.

(5) Effects of the error of AIS reported information on collision avoidance

data

The error in AIS reported target information (such as GNSS error, setting error of

GNSS antenna location) directly influences the accuracy of collision avoidance data

(CPA/TCPA).

6.6 System operational tests to determine data accuracy

.1 System diagnosis to test system status (including errors, failures)

(1) Activate self-diagnostic test routine automatically or at the request of the operator,

according to the work flow of the corresponding device manual.

(2) Establish regular maintenance schedule to ensure radar performance.

(3) Pay attention to the life expectancy of main parts such as the magnetron.

.2 Performance check by aid of system test programmes against known solutions

According to IMO resolution A. 823(19), operators should be able to evaluate system

status using prepared test programmes.



(1) Be familiar with prepared test programmes and related operational regulations for

special devices.

(2) Evaluate ARPA performance at regular intervals against known solutions as

described by 5.25.4.7.1 of resolution MSC.192(79), Performance Standards.

(3) Related symbols should be shown and identified by operators when test

programmes are working.

.3 Performance check by manual plotting, including trial manoeuvre

Radar target tracking performance can be checked through manual radar plotting.

The test programme is as follows:

(1) Tracks a clear and stable target ship by means of ARPA or TT, reads tracked data

and simulates the target motion data based on the own ship's trial manoeuvre.

(2) Manually plots the above target simultaneously and calculates target motion

information and the changed target motion information after the own ship's

manoeuvre.

(3) Check radar tracking performance by comparing the above calculated target

motion information with the target motion information from ARPA or TT.

.4 Anomalies of ARPA or TT and AIS reported information

Proper actions should be taken when data accuracy of ARPA or TT and the AIS

reported target does not meet relevant performance standards.

(1) Calibration of errors caused by radar sensor

Errors caused by the radar sensor include range and bearing measurement errors.

Refer to 2.2.5 of Part D for check and calibration of the errors.

(2) Calibration of error caused by THD and SDME

When data accuracy of heading and speed does not meet the relevant performance

standards, it is necessary to calibrate heading in THD and speed in SDME according

to equipment operation manual, or to terminate radar tracking and apply for repair

service.

(3) Proper management of anomalies of radar target tracking

According to the basic principles of radar target tracking, the phenomena of target lost

and target swap may occur in target tracking, which will result in the anomalies in

displayed data. Therefore, the operator should take correct actions. Refer to 5.6 of

Part D for details.

(4) Calibration of anomalies caused by AIS reported targets

Information anomalies of an AIS reported target relates to the own ship's sensors, the

AIS reported target and VDL of AIS. The information of the own ship's EPFS, THD and

SDME should be verified, together with the information of AIS reported target in

accordance with 6.2 of Part D.



In case of any anomalies in AIS presentation, the AIS reporting functions should be

switched off for repair service.


.1 Limitations of ARPA or TT and AIS reported information

(1) Limitations of radar tracking

(a) Tracking reliability.

Target lost and target swap were described in 5.6 of Part D. Limitations of processing

delays were summarized in 5.7 of Part D.

(b) Capacity

The capacity and availability of radar picture information are restricted by the size and

discrimination of the display. Meanwhile, hardware conditions also limit the maximum

tracking and displaying capacity of targets.

(c) Tracking range and speed

In accordance with the radar performance standards, target tracking facilities should

be available on at least the 3, 6, and 12 nm range scales. Tracking range should

extend to a minimum of 12 nm. When the targets proceed beyond the maximum

designed tracking distance (e.g. 12 nm), the radar will automatically give up tracking

for the target.

Speed limit exists for radar target tracking, and the maximum relative speed of the

normal tracking is about 100 knots (normal speed vessel) or 140 knots (high speed

craft).

(2) Possible errors in interpreting target data

Possible errors of interpretation of target data were outlined in 6.4 of Part D. The

instructor should emphasize that the errors are not inherent in the radar system, but

result from misunderstanding, inexperience or careless observation by the operator.

(3) Possible errors in displayed data of ARPA or TT

Possible factors that might cause errors in displayed data were identified and

explained in 6.5 of Part D. Due to the accuracy limitations in displayed data of ARPA

or TT; the OOW should not be over-reliant on displayed data of ARPA or TT and

should comply with basic principles in keeping a navigational watch.

(4) Limitations of the application of AIS reported targets on radar

Based on the description of AIS reported targets in 5.2, 5.3, 6.2, 6.3 of Part D, the

instructor should emphasize the limitations of AIS reported targets.

(a) Limitations of AIS reported targets

I. Errors in displayed data of AIS reported target



Errors in displayed data of AIS reported targets were described in 6.5.6 of Part D.

Refer to 6.5.6 of Part D for details.

II. No panorama of navigation situations by AIS

AIS, as non-autonomous detection equipment, cannot indicate islands, shorelines, or

navigation objects without being equipped with AIS devices. Not all vessels are

equipped with AIS devices, and those equipped may power them off at any time.

III. The reliability of AIS data used in collision avoidance

The assessment of the risks of collision should be based on the relative motion of

targets with respect to the own ship, and collision avoidance manoeuvres should be

by reference to water. However, AIS adopts geographical coordinates WGS-84, and

indicates targets' true motion to ground.

(b) Limitations of AIS assisting radar in preventing collisions

I. Display interference

In dense traffic waters, the AIS symbols may complicate and overload screen

information, or even cover up weak target echoes, and affect the normal radar

observations.

II. Complicated operation

The integration of AIS information results in complex human-machine interface and

incremental information. It requires more ongoing training for a radar operator to

understand the function of collision avoidance of the modern radar.

III. Data redundancy

On the radar display without association of tracked and reported targets, and owing to

the different data sources, processing methods and accuracies, there will be

differences between radar tracking data and AIS reported data for the same physical

target, which will result in screen data (including graphical and alphanumeric data)

redundancy. This produces difficulties for the OOW to properly assess encounter

situations.

IV. Lost target

Both radar and AIS may have undetectable or lost targets. For example, it is possible

for a small ship in clutter and equipped without AIS device to remain undetected either

by radar sensors or by AIS sensors.

(5) Limitations of association of radar tracked and AIS reported targets

Many factors influence the association of radar tracked targets with AIS reported

targets, including errors in radar tracking data and AIS reported data, association

algorithm, and the setting of association criteria, all of which can cause association

anomalies.

(a) Anomalies in association of individual or partial targets



These are usually caused by AIS data errors of targets. The difference between radar

tracking data and AIS reported data may also contribute to such phenomena. For

example, in case of a larger difference between the position of a radar tracked target

and that of an AIS reported target or a large target vessel of LOA longer than 250 m,

with a distance of more than 200 m between the leading edge of the radar echo return

and the AIS target reported position (master GNSS antenna), in addition to the

influence of weather/sea conditions and radar system errors and other factors, the

difference between the radar tracked and the AIS reported position may exceed 300

m.

The actual update interval of AIS reported information may be longer than the nominal

values as affected by the specific equipment performance and communication

environment at sea. This might cause a delayed update of the AIS reported position.

(b) No associations for all targets

If all the AIS symbols deviate at a fixed range from the radar echoes, it is probably due

to all the sensor errors of the own radar system. For example, the association cannot

be realized due to the errors of the radar detection or the errors of the own ship's

EPFS, even though the positions of AIS reported targets (the GNSS positions of target

ships) are correct.

.2 Proper reactions to operational alarms

The operational alarms of ARPA or TT and AIS functions are based on the principles

of radar target tracking and the proper application of the related functions under

specific navigational situations.

(1) Reasonable operational alarms by setting up reasonable parameters.

(a) Set up reasonable guard zones, acquisition zones, restricted zones and exclusion

zones on the basis of the navigational situations and needs, in order to attain or

restrict new target alarms. Refer to 6.1.6 of Part D for details.

(b) Set up reasonable safety threshold value of CPA LIM/TCPA LIM in order to

attain reasonable dangerous target alarm. Refer to 6.7.3 of Part D for details.

(2) Reasonable acquisition mode

(a) The operator should determine reasonable acquisition modes according to actual

navigation needs since manual acquisition and automatic acquisition have their own

advantages and disadvantages respectively.

(b) Automatic acquisition, as a supplementary means to manual acquisition, is

suitable for open sea with good weather and sea conditions.

(c) Automatic acquisition is not suitable for a complicated echo environment which

needs more selection for targets.

(d) For any encounter situation, appropriate settings of automatic acquisition assisted

with exclusion zones are recommended.

(3) Ways to deal with operational alarms



Refer to 6.3.9 of Part D for basic ways to deal with operational alarms. The

operational alarms include target capacity overflow alarm, target lost alarm, new

target entry alarm and dangerous target alarm. For dangerous targets, the operator

may take the advantage of trial manoeuvre to make an informed decision for collision

avoidance. Refer to 6.3 of Part D for details.

.3 Hazards of small predicted passing distances (CPA and BCR)

In order to avoid limitations of radar target tracking as much as possible, small

predicted passing distances (CPA or BCR) should be avoided in any case.

Appropriate safety threshold values of CPA LIM/TCPA LIM should be set up in order to

attain a reasonable dangerous target alarm.

Many factors need to be considered while setting up the CPA LIM and TCPA LIM.

Refer to 6.1.4 of Part D for details.

.4 Sensor input alarms only valid for failure of input and not responding to inaccurate inputs

The sensor input alarms only occur on input failure and do not respond to inaccurate

inputs. So trainees should be cautious in making use of manual input.

(1) Radar sensor

When a radar sensor does not work, the sensor input alarms will be activated and

there will be no targets or clutter on the radar screen. In this case, the service

technician needs to replace the magnetron or MIC or maintain a bearing system

according to the related examination results, and correct range and bearing error. The

whole maintenance details should be recorded in the radar logbook.

In case of inaccurate inputs, the alarms will not occur. However it will affect the

accuracy of radar ranging and bearing measurements, including the association of

radar tracked targets with AIS reported targets. The errors of radar ranging and

bearing measurements should be checked and calibrated. Refer to 2.2.5 of Part D for

details.

(2) THD sensor

When the gyrocompass or THD does not work, the sensor input alarms will occur.

According to resolution MSC.192(79), Performance Standards, the equipment should

switch automatically to the unstabilized head up mode within 1 minute after the

azimuth stabilization has become ineffective. So the function of radar target tracking

and the AIS reporting will stop. The other THD sensor should be input if available. The

malfunction should be reported to the master or the cause of the malfunction should

be checked.

In case of inaccurate THD inputs, the alarm will not occur. Proper actions should be

taken, referring to 6.6.4 of Part D for details. When data accuracy of THD gets lower,

the true data of radar TT and relative data of AIS reported targets have errors. This

influences the association of radar tracked targets with AIS reported targets.

(3) SDME sensor



When the SDME or speed log is not functional, the sensor input alarm will occur.

ARPA or TT will automatically stop functioning within a limited time. In this situation,

the operator may input speed manually in order to make the ARPA or TT keep

functioning. The malfunction should be reported to the master and the cause of the

malfunction should be checked.

In case of inaccurate SDME inputs or inaccurate manual speed inputs, the alarm will

not occur. Proper actions should be taken, referring to 6.6.4 of Part D for details.

When data accuracy of SDME gets lower, the true data of radar TT and relative data

of AIS reported targets have errors. This influences the association of radar tracked

targets with AIS reported targets.

(4) EPFS sensor

When the EPFS does not work, the sensor input alarm will occur. Time and position

are absent for the radar system, which causes the function of AIS reported targets and

navigation with ECDIS to cease working. The other EPFS sensor should be input if

available. The malfunction should be reported to the master or the cause of the

malfunction should be checked.

In case of inaccurate inputs of EPFS sensor, the alarm will not occur. This might affect

the data accuracy of time and position of the radar system, as well as the accuracy of

AIS reported targets. Proper actions should be taken and refer to 6.6.4 of Part D for

details.

(5) AIS sensor

When the AIS does not work, the sensor input alarm will occur. AIS reported targets

cannot be displayed. The OOW should try to find out the cause of the failure and

report to the master as soon as possible.

In case of inaccurate inputs of AIS reported targets, the alarm will not occur. However

it will affect the accuracy of AIS reported targets and the association of radar tracked

targets with AIS reported targets. Proper actions should be taken and reference made

to 6.6.4 of Part D for details.

Demonstration and practical training 5 & 6 -1 Operation of ARPA or TT and AIS reporting functions


To help trainees consolidate the theory part and to achieve proficiency in using ARPA

or TT and AIS reporting functions for collision avoidance.

(2) Training mode

Demonstrate and operate hands-on on radar simulator.


(a) set up and maintain ARPA or TT and AIS reporting functions correctly (2.0 h)



(b) operate radar target tracking function correctly (4.0 h)

(c) use radar target tracking function to assess encounter situations and collision

dangers (4.5 h)

(d) associate tracked targets with AIS reported targets (3.0 h)

(e) operate trial manoeuvre (1.5 h)

Detailed practice items and timetable

Procedure Item

Demonstration

and practical

training time

hrs

set up and maintain

ARPA or TT and

AIS reporting

functions correctly

1．describe the preparatory work for radar start up 0.2

2．start radar and maintain the optimum display of echoes 0.8

3．select range scale, presentation mode, and describe cautions 0.2

4．set up and check sensors and system parameters 0.8

operate radar target

tracking function

correctly

5．manual acquisition: describe the criteria of manual acquisition,

advantages and disadvantages as well as applicable situation 0.5

6．automatic acquisition: set up automatic guard/acquisition and

exclusion zones, record target acquisition/alarm, describe the

criteria of automatic acquisition, advantages and disadvantages as

well as applicable situation

0.5

7．select relative vector or true vector, describe their characteristics

and functions, and record each condition with change in

speed/course

1.5

8．record the past positions of target, make alteration of time

interval and record again, describe the status of past positions of

target

1

9．cancel target tracking 0.2

10．record target lost and the corresponding environment/condition 0.3

use radar target

tracking function to

determine

encounter

situations and

11．graphically record the procedures of determining the safe,

dangerous, and imminently dangerous targets in association with

relative vector and CPA circle and determine encounter situations

by means of true vector

2.5

12． simultaneously record the data of safe, dangerous, and 1



collision dangers imminently dangerous targets in alphanumeric display

13．record the procedures of determining the safe, dangerous, and

imminently dangerous target and determining encounter situations

by means of PADs (if applicable)

1

associate tracked

targets with AIS

reported targets

14．record and compare the radar tracking data and AIS reported

data of the safe, dangerous, and imminently dangerous target 1

15．record and compare the association of radar tracked targets

with AIS reported targets in different association criteria 2

Operate trial

manoeuvre 16．record the use of trial manoeuvre 1.5

Notes:

All the above 16 items cover resolution MSC.192(79), Performance Standards.

The remaining 14 items except Items 14 and 15 only cover A. 823(19) and A.

422(XI) ARPA performance standards.


Assessment upon completion of the Topics 5 and 6 can be conducted in forms of

written examination, oral test, practical demonstration, exercise scinarios, discussions

and class records in order to assess whether a trainee satisfies the required

performance. Focusing on the application on radar collision avoidance both in terms

of principles and practical training, the trainee should:

(1) have requisite knowledge of the basic principles of ARPA or the association of

radar tracked targets with AIS reported targets;

(2) understand the limitations of radar automatic tracking systems and AIS sensors;

(3) have the practical ability to set up and maintain ARPA or TT and AIS reporting

functions in optimal working condition;

(4) acquire targets manually and automatically;

(5) associate radar tracked targets with AIS reported targets appropriately;

(6) assess the encounter situations and risks of collision by using ARPA or TT and AIS

reporting functions;

(7) have extensive knowledge of possible mistakes when interpreting the target

information; and

(8) identify and explain the causes of error in display data; be aware of the risks of

over-reliance on ARPA or TT and AIS reported information.



Teaching guidance

The operation of radar target tracking is a crucial part of competence of the officer in

charge of a navigational watch. When giving classes, the instructor should emphasize

that improper setting, adjustment, and incorrect operations of radar video processing

control will affect radar detection performances and impose adverse influences on

radar target tracking. Particularly, some operations, such as the setting of a radar

system and the checking of sensors information as well as the setting of CPA

LIM/TCPA LIM, are critically important for the OOW to obtain collision avoidance

information. Besides, the instructor should also emphasize that the setting of CPA

LIM/TCPA LIM may be subject to restrictions in narrow channels and complex waters

with multiple targets.

It is advised that the instructor assist the trainees to select proper presentation modes

by demonstration. The azimuth unstabilized H-up orientation presentation mode is not

applicable for the functional operation of ARPA or target tracking; N-up true motion

presentation mode is better when a radar is used for navigational purposes; while

C-up relative motion presentation mode is better for collision avoidance. Therefore,

when the vessel are engaged in both collision avoidance and navigation situations,

the true motion C-up or N-up presentation mode should be selected based on the

main application of radar.

In class, the instructor should help trainees understand the significance of the

principles of data smoothing for radar target tracking. Processing delay, on the one

hand, is necessary data processing for a TT facility; and on the other hand is one of

the main radar limitations as well.

Proper use of vector is the key for ARPA or TT application and also for teaching. The

characteristics of relative and true vector should be emphasized during collision

avoidance; both vectors should be flexibly switched to take both collision risks and

collision avoidance decisions into account.

The instructor should attach importance and significance to comprehensive

consideration of both tracked and reported information in collision avoidance

situations. AIS only provides supplementary information and should not substitute

radar tracked target information in collision avoidance. AIS information might not meet

the requirements of the AIS protocol, information update interval might delay, or

information might be incomplete or erroneous. Therefore, many factors could affect

the accuracy of the AIS reported information. Because AIS reported information has

no integrity monitoring, the information should be confirmed by the user prior to use.

It might be a difficult part for trainees to apply the information of both radar tracked

targets and AIS reported targets for collision avoidance. The instructor should focus

on the limitations of AIS information and demonstrate the influences to the AIS

reported targets presentation when the radar has a lack of information from various

sensors. Radar tracking information and AIS reported information come from two

different sensors. When radar tracked targets and AIS reported targets are associated,

the AIS data should be verified first. If the verification is passed, the accuracy of AIS



reported data is generally higher than that of radar tracked data. It is advised that the

instructor clearly explain the effects on the association of radar tracked targets and

AIS reported targets when different association criteria are set. If the association

criteria are set appropriately, radar tracked targets and AIS reported targets may be

associated properly; if the association criteria are inappropriate, radar tracked targets

and AIS reported targets could be rendered as two distinct targets. In this situation it is

recommended to use ARPA or TT targets.

In teaching, emphasis should be laid on the fact that the past position function only

indicates target (or the own ship) positions within a period of time in the past by

smoothing techniques, but not the present or future movement. In order to understand

and illustrate the dynamic movement of a tracked target comprehensively, there must

be considerations regarding past positions in combination with the information of

vectors of the present tracked target. The true vector in combination with past

positions can be used to determine the manoeuvring of a target ship, while the relative

vector associated with past positions cannot clearly indicate the manoeuvre state of

the target.

Focus in class should be on the fact that the purpose of using trial manoeuvres before

the actual manoeuvre is to simulate the action effectiveness. This function should be

used as early as possible in accordance with regulation 8 of the COLREGs. The trial

manoeuvre can assist navigators to assess the encounter situations in advance so as

to avoid close-quarters situations and reduce the ship's deviation. If it is safe and

practicable, the ship should resume the original course and speed after the collision

risks have been lifted.

Throughout this course, the instructor should remind the trainees that TT/ARPA can

only be used as an aid to assist navigators to avoid collision and reduce workload

during bridge watch, but it cannot exempt or eliminate the navigator's look-out

responsibilities.

This course meets resolution MSC.192(79), Performance Standards . Training

institutions whose equipment meets ARPA standards only may skip the parts about

AIS reported targets.



7 Application of COLREGs when using radar


This topic covers the following major issues: proper use of radar to keep a proper

lookout, factors affecting safe speed in association with radar, methods and its

characteristics for sufficient radar information acquisition, and the COLREGs

requirements to take actions based on radar information.

This topic represents a comprehensive application of prior knowledge. The key

information of a target ship can be acquired by means of radar target tracking, radar

target tracking assisted by AIS reported information and radar plotting. Appropriate

actions may be taken to avoid collision or close-quarters situations on the basis of

analysis of the system and application of the information.

7.1 Proper use of radar and full and complete interpretation of radar information

Radar is useful in determining the bearing and range of a target ship, even when they

cannot be determined by other means. What is more, with radar target tracking (ARPA

or TT), AIS reported information or manual plotting, the key and accurate information

for collision avoidance such as CPA, TCPA, course and speed of the target ship can

be obtained to assist the officer in handling collision avoidance or close-quarters

situations. It is highly necessary and important to determine risks or potential risks of

collision through systematic radar observation and complete interpretation of the

radar information. For proper use of radar, the following should be fulfilled:

(1) Full account shall be taken of the characteristics, efficiency and limitations of the

radar; familiarization should be developed with the function of every switch and button

on the control panel and operation menu of radar; familiarization should also be

developed with the methods and measures to eliminate all kinds of interference. It is

important to possess the ability to make a correct estimate of the errors with radar. It

should be noted that: small or weak echoes may not be detected; incorrect operations

may cause undiscovered targets or lost tracked targets; inappropriate configuration of

radar or radar sensors may produce insufficient collision avoidance information.

(2) Proper range scale should be selected appropriate to the prevailing circumstance

and conditions, and the range scales should be switched at sufficiently frequent

intervals making it possible to avoid missing small targets in the vicinity and obtain

early warning of the risks of collision. Therefore, the trainee is able to read radar

information correctly and sufficiently and make a full appraisal of the situations and

the risks of collision.

(3) A good command of the characteristics, advantages and limitations of radar

display modes should be achieved. Proper display should be selected appropriate to

the prevailing circumstances and conditions, i.e. correct selection of true motion or

relative motion presentation under effective azimuth stabilization, such as north-up

presentation or course-up presentation. This is very important for systematic radar



observations and complete interpretation of radar information. The trainees will

probably have their own individual preferences when starting the course but should be

encouraged to become familiar with a variety of display modes so that they can

manage the usage of the equipment in certain circumstances.

(4) Skilful and proper use of fixed range rings (RRs), VRM, EBL, parallel Index Line,

cursor; the mechanical bearing scale (if available) on the radar screen should be

maintained.

(5) Systematic radar observation must be continuous and uninterrupted.

(6) Visual look-out must be maintained when using radar, whether or not visibility is

restricted.


Safe speed refers to a speed at which a ship can take proper and effective actions to

avoid collision and be stopped within a distance appropriate to the prevailing

circumstances and conditions. Every ship must use safe speed at all times. Safe

speed is a relative concept, which varies with the ship state and the circumstances

and conditions. The following factors (but not limited to) shall be taken into account for

ships with operational radar when determining a safe speed:

(1) The characteristics, efficiency and limitations of radar equipment. For example,

radar observations cannot provide as much direct and large amount of information as

visual look-outs. It takes more time to track or plot targets, and radars respond slowly

while the target ship is manoeuvring. All information from radar has certain errors.

(2) Constraints imposed by the radar range scale in use. For example, when using the

longer range scale, the target echo is poor, discrimination is low and small targets in

the vicinity are less likely to be detected. The target ship at a long distance cannot be

detected in a timely manner and it is difficult to give an early alarm when using short

range scales.

(3) The effects on radar detection of sea state, weather and other sources of

interference. It mainly refers to the effects on radar detection by sea clutter, rain and

snow clutter, radar interference, multiple echoes, indirect echoes, side-lobe echoes,

and irregular propagation. If serious, even the echo of large vessels cannot be

identified, which is very dangerous for ship collision avoidance.

(4) The possibility that boats, ice and other floating objects may not be detected by

radar at a modest range. These small targets have weak electromagnetic wave

reflection ability.

(5) The number, location and movement of ships detected by radar reflect traffic

density and the relationship between the own ship and other target ships.

(6) An assessment of visibility can be made when radar is used to determine the

range of ships or other objects in the vicinity. It is very important when visibility may

change or at night.



7.3 Methods and characteristics of acquiring sufficient radar information

According to the requirements of the COLREGs, "radar plotting or equivalent

systematic observation of detected objects" should be used to determine whether

risks of collision exist. With the development of radar technology, the utilization of

manual plotting is decreasing, and radar target tracking is more and more widely used.

Since the time Resolution MSC.192(79) has taken effect, AIS as the required sensor

of the radar system makes it possible to establish the association of radar tracked

targets with AIS reported targets. As a result, application of radar in collision

avoidance becomes more and more improved. As a matter of course, the use of either

manual plotting, or radar target tracking, or AIS reporting, or the association of tracked

targets with AIS reported targets, on the premise of correct use of the radar, provides

sufficient information for situation awareness and ship collision avoidance. The

trainees should understand and master the following approaches as much as

possible:

(1) Radar plotting. Through systematic and continuous observation of the bearings

and distances of radar echoes of an approaching ship, plotting on the radar screen (if

fitted with reflection plotting equipment) or on manual plotting paper can be done to

acquire the collision avoidance information, such as course, speed, CPA, TCPA,

measures and timing of collision avoidance, and the timing of resuming original

motion status. This plotting takes a long time and only a small number of targets can

be plotted. In case of any action taken plotting should be recommended after the ships

are in stable motion conditions. The training of manual plotting is useful for developing

spatial thinking in situation appraisal, predicting the movement trend of the target ship

after the own ship takes action to avoid collision and for coordination with other ships

in encounter situations. In this way, the effectiveness of collision avoidance can be

guaranteed. This training is compulsory for beginners.

(2) Target tracking. Radar tracking equipment can predict and update target ship

tracks and optimum motion data based on synthesis processing and continuous

calculation of relevant sensors' information. This method acquires the key information

for collision avoidance, handles more targets in a short time, and tracks continuously

with high data accuracy, which is the primary approach for ship collision avoidance at

sea.

(3) AIS reported targets. AIS reported targets provide graphic and alphanumeric

display modes on radar screen. Graphical display presents the types of AIS targets,

the positions to the own ship, and indicates the course and speed of the AIS target by

the predicted vector. The following data should be presented in alphanumeric form:

source of data, MMSI, navigational status, position and its quality, range, bearing,

course, speed, CPA and TCPA, heading, ROT, and other related information. In case

the CPA/TCPA of an AIS target is less than the CPA LIM/TCPA LIM, a danger alarm

will be activated. It is easy to use, but should be noted for its error.



(4) The association of radar tracked with AIS reported targets. Based on radar target

tracking, proper association between AIS reported targets and radar tracked targets

assists radar collision avoidance, reduces the redundant information and clutter on

screen, and acquires optimal information for collision avoidance, all of which are

obvious advantages.

7.4 Actions to avoid collision based on sufficient radar information and in accordance with COLREG rules

Based on radar information, the instructor should train the trainees to be able to

analyse the potential or existing risks of collision and to determine and take actions to

avoid the close-quarters situations. The actions taken must be in compliance with the

COLREGs. Trainees should be trained to do the following:

(1) Make sure that any action to avoid collision shall, if the circumstances of the case

admit, be positive, made in ample time and with due regard to the observance of good

seamanship. Any alteration of course and/or speed to avoid collision shall, if the

circumstances of the case admit, be large enough to be readily apparent to another

vessel observing visually or by radar; a succession of small alterations of course

and/or speed should be avoided.

(2) State the responsibilities between vessels under different circumstances and

conditions. For instance, give-way vessels and stand-on vessels, vessels with same

collision avoidance responsibilities, vessels required not to impede and vessels not to

be impeded.

(3) State the principles of alteration of course and/or speed and good seamanship to

avoid collision in sight of one another, such as in overtaking situations, head-on

situations, crossing situations and collision avoidance between ships with different

operational ability.

(4) State the principles of alteration of course and/or speed and good seamanship

practice to avoid collision when navigating in or near an area of restricted visibility (not

in sight of one another).

(5) State the coordinated action between the own ship and the target ship in collision

risk or close-quarters situations. Coordinated action means that the changes in the

course and (or) speed of the own ship and the target ship can lead to the same

changes in the relative motion line. This means that the CPA is increased at the same

time, which can be verified by the trial manoeuvre and manual plotting.

(6) The two ships in a collision relationship should check the effectiveness of action

carefully until the other ship is finally past and clear. Then the give-way vessel may

determine whether to resume the original course and/or speed.

Arrangements should be made to simulate the above training. Every trainee should

frequently practice radar collision avoidance operation assisted by manual plotting,

target tracking, AIS reported information, and target association. In these exercises,

trainees should be able to interpret sufficient information presented on radar for



collision avoidance, and to analyse the risks of collision and take appropriate actions

to avoid these risks.

Simulation of previous collision incidents and study of court judgments can be an

effective way for trainees to learn from earlier navigational mistakes.

7.5 Use of radar

In clear weather in the daylight, the officer in charge of a navigational watch should

carry out radar practice to obtain an appreciation of equipment capabilities and

limitations, to compare radar and visual observations and obtain an assessment of the

relative accuracy of information. There should be early use of radar in clear weather at

night and when there are indications that visibility may deteriorate, so as to make an

early and full appraisal of the situation. The officer in charge of a navigational watch

should use the radar whenever restricted visibility is encountered or expected, and at

all times in congested waters, but have due regard to its limitations.

Demonstration and practical training 7-1 Ship handling for integrated collision avoidance


(a) Proper and systematic use of radar to acquire sufficient target information.

(b) Correct analysis and application of the radar information, in close association with

the COLREG rules.

(2) Training mode

The trainees should complete typical training programmes on the radar simulator set

by the instructor and answer related questions. It is advisable to use a full mission

marine simulator with visual scene when the trainees carry out the training

programmes for ships in sight of one another.


(a) Start the radar simulator, select the appropriate radar presentation mode and

range scale, adjust the radar picture, and set up the radar system sensors and CPA

LIM/TCPA LIM (0.4h);

(b) Sufficient radar information of a target ship such as course, speed, CPA and TCPA

can be acquired by manual plotting, radar target tracking, AIS reporting and the

association of radar tracked with AIS reported targets. Therefore, the risks of collision

and encounter situations can be assessed based on the information (N.B. 1. It is

advised that the following six scenarios are completed: overtaking situation, head-on

situation and crossing situation of vessels in sight; the approaching ship from forward

of the beam in restricted visibility (not in sight); the approaching ship from the abeam

and abaft the beam; and good seamanship. 2. Assumption shall not be made on the



basis of scanty radar information. 3. The frequency of manual plotting should be

moderate at first, and then increased as the trainees gain more competence. It is

advised that the exercise start with between 3 and 5 targets while avoiding

close-quarters situations). (0.6 h×6)

(c) When the CPA of a target ship is less than the CPA LIM, the collision avoidance

actions of the own ship should be determined by manual plotting or trial manoeuvre

before manoeuvring according to the COLREGs. Any action to avoid collision shall be

taken in accordance with part B of COLREG and shall, if circumstances admit, be

positive, made in ample time and with due regard to the observance of good

seamanship. Action taken to avoid collision with another vessel shall be such as to

result in passing at a safe distance. The effectiveness of the action shall be carefully

checked until the other vessel is finally past and clear. (0.4 h×6)

(d) Comprehensive navigation training in multi-vessel encounter situations and varied

environmental conditions in association with typical cases. (4 h)

(e) At the end of the session, the instructor is advised to interact with the trainees

about their training experiences, gains and doubts. The instructor should make

comments and offer solutions accordingly regarding the problems and highlights of

the course (by replaying training video or retrieving training data). (1 h)

(f) Sample training report may be filled for each exercise scenario. (Table 7-1) (0.6 h)



Tab.7-1 Sample Training report

Own ship Target ship information

Own ship's action

Target ship's action

CP

A a

fter c

ollis

ion

avoid

ance

Action plan Practical action

Course Speed Information

Methods Bearing Distance Course Speed CPA TCPA Time

Course

alteration

Speed

change Time

Course

alteration

Speed

change Time

Course

alteration

Speed

change

Manual plotting

Auto-plotting

AIS target

Association

Com

paris

on a

nd a

na

lysis

of ra

dar

info

rmatio

n o

bta

ined b

y d

iffere

nt

meth

od

(Including information acquisition method, the comparison of different methods, error and influence factors, information analysis.)



Note: "Action plan" is the outcome of manual plotting and trial manoeuvre of the other three methods.

Rule

s a

pp

licatio

n

(Including the applicable rules, basis, avoidance effect and cautions.)




Assessment upon completion of the this topic can be conducted by written

examination, oral test, practical demonstration, exercise scenarios, discussions and


performance and competence. In focusing on the application of the COLREGs on

radar collision avoidance in practical training, the trainee shall

(1) operate radar properly and in a timely manner;

(2) maintain a proper lookout to acquire sufficient information from radar;

(3) be familiar with the COLREGs and be able to apply them correctly;

(4) complete the training report correctly.

Teaching guidance

According to the requirements of the STCW Code, radar, use of “including application

of COLREG”. In the teaching process, it is advised that the instructor integrate

demonstration and previous collision incidents and the trainees conduct frequent

practices on the radar simulator for better outcome.

In this topic, the demonstration and practical training part is one of the key

components. When designing the training programme (Tab.7-2), the instructor should

take full account of the training for the proper use of radar to acquire sufficient radar

information, the application of the association of radar information and the Rules, the

integration of typical cases into the training program, the conditions of the teaching

equipment and the requirements of the competent authorities. At the beginning of the

training, the instructor should make clear the training programmes, contents,

requirements and notes. In the course of the training, the instructor should

continuously monitor the trainees' operation and correct improper ones and violations

wherever appropriate. The instructor should also assume the responsibility of the

target ship collision avoidance and VHF communication, so as to ensure trainees'

comprehensive and proper understanding of the Rules. At the end, the instructor

should give feedback and comments, with emphasis on the comprehensive and

proper application of the Rules as well as the necessity of completing the training

report. The time for trainees' operation in practical training should not be less than

three quarters of the total demonstration and practical training time.

By using different effective teaching methods, such as case studies, the instructor is

supposed to let trainees understand the related rules in the COLREGs and apply the

Rules properly in association with radar information. In the teaching process, the

instructor should emphasize the time and conditions to apply the Rules, the

responsibilities between two ships under different circumstances and different

conditions and the coordination of actions between the own ship and target ships.

These should be priorities in the training programme.



APPENDIX 1

Tab.7-2 A sample of training programme

(It is advised that the programme be designed step by step, so that it can be used at any time.)

Elements of training

programme Specific content Remarks

Use radar correctly Performance standards Carry out practical training frequently according to

different elements.

Environmental

conditions Open waters

It may be in restricted waters, narrow channels,

waterways, TTS, even fishing areas, congested

waters. The radar presentation may be different.

Visibility Good visibility, in sight

In addition, it is suggested to set up restricted

visibility not in sight and restricted visibility in sight,

which may apply to the different Rules.

Hydrological and

meteorological

conditions

Rain, snow,

sea wave

Clutter depression training, other interference may

also be considered.

Encounter situations Head-on

Other encounter situations may be considered:

overtaking, crossing, the vessel forward of beam in

restricted visibility (not in sight), the vessel abeam

and abaft beam, good seamanship.

Encounter distance 7-11 nm It can be from long distantce to short distantce, even

immediate danger.

Velocity ratio

between own and

the target

About 1:1 It may be from small too big.

Target ships

A dangerous target, a

ship with the same

course and the same

speed and a ship at

anchor

It can be from less to more.

Manoeuvrability

Close tonnage of the

same type of ordinary

cargo ship

Different type of vessels may be selected (especially

the special function vessel). Tonnages may be from

small to big.

Typical cases Relevant information Case database can be established.

Safety components are too important to be neglected in teaching. The instructor and

trainees should have safety awareness throughout the teaching process. The

instructor should carry out safety inspection before starting the radar and simulator,



complying with safety operation procedures and keeping the radar and simulator in

the best working state to ensure safety of navigation.



APPENDIX 2

Examples of lesson plan

.1 An example of lesson plan for lecture

Topic 1 Describe the basic theory and operation of a marine radar system

Sub-topic 1 Describe the fundamental principles of radar correctly

Training Objective: State the configuration of a marine radar system LESSON NUMBER: Class hours: 0.6 h

Knowledge, Understanding and Proficiency

Teachin

g

method

Textboo

k Ref.

Instructor

guideline

s

Class

hour

1.1.2 State the configuration of a marine radar system Lecture T1;T2 R1;R2

R4;R6 A1 0.6

(1) according to Fig.1-1 (the configuration of marine radar system), state the necessary sensors for the radar

system, including basic radar, THD, SDME, EPFS and AIS; optional sensors: ECDIS; output devices: ECDIS

and VDR.

0.1

(2) state the signals that radar sensors provide for the radar information processing system: trigger pulse, heading

line, bearing signal and video signal. 0.1

(3) state that the gyro-compass/THD sensor provide heading line signal for the information processing system of

the radar.

0.1

(4) state that the SDME sensor provides STW and SOG for the information processing system of the radar. STW is

from speed log, or manual input; SOG is from LOG, GNSS, the TT function of radar, or manual input.

(5) state that the GNSS sensor provides the WGS-84 position and UTC time for the information processing system 0.05



of the radar.

(6) state that the AIS sensor provides static information, dynamic information and voyage information for the

information processing system of the radar.

(7) state that ENC provides hydrological geographic information for the information processing system of the radar.

(8) describe the information processing system of the radar:

(a) state the importance of the heading signal for bearing-stabilized picture display, combining article 9.1 of

resolution MSC.192(79), Performance Standards; state the importance of heading signal for normal display of

ENC and AIS information;

(b) state the importance of SOG for navigation, and the importance of STW for collision avoidance;

(c) state radar TT function based on sensors, heading and speed information;

(d) state the significance of GNSS information integrity for outputting data accuracy of information processing

system;

(e) state the significance of AIS information for radar collision avoidance, and lay a foundation for radar tracked

and AIS reported target association;

(f) state the significance of integrated information overlay (which includes ENC data, radar images, tracked and

AIS reported targets) on radar display.

0.25

(9) state the significance of VDR recording radar information.



APPENDIX 3

An Example of lesson plan for practical training

Topic 5 & 6 Operation of ARPA or TT and AIS reporting functions

LESSON NUMBER:

DURATION: 0.8 h

Practical training 5 & 6 -1: Operation of ARPA or TT and AIS reporting functions

Training objectives: Setting up and maintaining ARPA or TT and AIS reporting functions correctly - Setting up and checking sensors

and system parameters

KUPs/Required performances

Teachin

g

method

Textbooks Reference

s

Instructor

guidelines Time h

6 Operation of ARPA or TT and AIS reporting functions/

Setting up and maintaining ARPA or TT and AIS reporting functions correctly

- Setting up and checking sensors and system parameters

D* P* T1;T2;T3 R1;R2

R5;R7 A1

22/1

D* P*

(1) checking OS (the own ship) course: confirm that the radar heading is consistent with the indication

of the gyrocompass, otherwise make corrections according to the manufacturer's manual. √ √ 0.05 0.05

(2) checking OS speed: confirm that the speed data of OS on radar display is STW, and is consistent

with that of water track speed-log, otherwise make corrections according to the manufacturer's √ √ 0.05 0.05



manual.

(3) checking OS position: confirm that the position data of OS on radar display is consistent with that of

EPFS, otherwise make corrections according to the manufacturer's manual. When the position

data is checked, the integrity information of EPFS should also be confirmed.

√ √ 0.1 0.1

(4) verifying AIS information: confirm that the RAIM of OS GNSS information is satisfactory; ensures all

the AIS information is displayed; verify the AIS information of nearby ships via VHF radiotelephone. √ √ 0.1 0.2

(5) setting up CPA LIM/TCPA LIM: set up CPA LIM/TCPA LIM appropriately according to navigation

circumstance, ship's maneuverability, and give the reasons. √ √ 0.1 0.2

Teaching guidance: (a) it is a comprehensive training process to operate ARPA or TT and AIS reporting functions. It should be emphasized that

the radar image should be adjusted properly before carrying out above training items.

(b) the knowledge (3) and (4) may not be involved for those ARPAs which do not meet the requirements of resolution

MSC.192(79), Performance Standards.



Ex.1 SIMULATOR EXERCISE (3.0 Hours)

To Set up and Operate Radar in Accordance with Manufacturer's Instructions

Teaching Guidance

The trainee sets up and operates specific functions on the Radar.

Demonstrate the following tasks on Radar while navigating safely in a Coastal sea

setting with non-threatening Radar targets:

Turn on the Power of the Radar from Stand by (trainee must report checks

prior starting Radar);

Adjust the controls of the

o Brightness, Gain, and Tuning (Trainee must report reason of

preference for manual or auto tuning);

o Sea and Rain Clutter control (Trainee must report reason of preference

for manual or auto tuning);

o Range (Trainee must report reason of preference for Range scale

chosen);

o Range Rings (Trainee must be able to toggle On / Off);

o VRM and EBL (Trainee must be able to Offset VRM/EBL).

Select Screen Display Day or Night;

Report S-Band/X-Band and Radar transmission Pulse length

Instructor must now Start Exercise;

Set Off centre view;

Select Ground stabilized / Sea Stabilized mode (Trainee must report Speed

input selected);

Select Relative Motion / True Motion (Trainee must observe True motion Own

ship Reset function);

Select Orientation North up/Head up/Course up;

Locate Heading line and sets Heading line 'Off ';

Locate Ship's Position and Time on display screen;



Select Vector mode True / Relative and set Vector time;

Select Trails True / Relative and set trail time;

Select Parallel Index Lines and edit line distance and heading;

Instructor must now reduce visibility and simulate rough weather and add a

few targets;

Report visibility and make a Blind Sector Sketch;

Manually acquire the target and read Target Data (Target Identification/ Name,

Range, Bearing, STW/SOG, CSE/CMG,CPA, TCPA, BCR, BCT);

Select AIS 'On' (if UAIS transponder connected) and

o read UAIS Targets data;

o read Additional UAIS data (MMSI, Heading, Navigational status, Ship

type, IMO number, Call sign, Ship name, port of destination);

o differentiate between Radar and AIS target symbol;

o Differentiate between AIS Sleeping / Active targets;

o Check settings for AIS and Radar target association.

Instructor guidelines

Conduct simulation exercise according to exercise description:

o Set simulation parameters;

o Brief and debrief trainees;

o Assess accomplishment of tasks according to exercise description.

Expected outcomes:

Familiarize with the setting up and use of Radar functions;

Navigate with Radar.



Ex.2 SIMULATOR EXERCISE (4 Hours)

Using radar to ensure safe navigation

Teaching Guidance

The trainee sets up and operates specific functions on the Radar.

Demonstrate the following tasks on Radar while navigating safely in a Coastal sea

including a TSS with non-threatening Radar targets and preferably where Radio

beacons are present:

Switch “On” Radar and Tune Radar to Exercise scenario settings;

Sets the CPA and TCPA Alarm settings;

Import Route or Plan a Route of 2 or 3 waypoints;

Use Nav Lines Function to mark TSS on Radar.

Instructor must now Start Exercise:

Fix Position on Chart using Radar Ranges/Bearings and Radio Beacons;

o Compares Fix with that from EPFS.

Select Parallel Index Lines and edits line distance and heading with Object

and monitors safe passage distance;

Manually acquires the targets (Radar / UAIS) and determines dangerous

targets (Report to Instructor when asked to identify the dangerous targets on

his screen);

Uses Range scales effectively.

Instructor must now simulates a SART target:

Report SART target to instructor.

Instructor guidelines:





Expected outcomes:

Familiarize with the use of Radar functions;



Navigate with Radar.

Exercise 3A MANUAL RADAR PLOTTING (1.5 Hours)

Whilst steering 024°(T) at 15 knots, the following observations of a target

were made on the Radar screen.

Ship's time Bearing (T) Range (miles)

0900 345° 7.0

0903 345° 6.4

0906 345.5° 5.75

0909 344.5° 5.0

0912 337° 3.9

0915 327° 2.9

0918 308° 2.1

Use the Radar Plotting Sheet to work out below:

Find

(a) The initial CPA, TCPA, Course and speed of the target;

(b) The NEW CPA, TCPA, Course and speed of the target.



Exercise 3B MANUAL RADAR PLOTTING (1.7 Hours)

Whilst steering 044°(T) at 15 knots, the following observations of a target

were made on the Radar screen.

Ship's time Bearing (T) Range (miles)

0930 105° 14.0

0936 105° 11.5

0942 104.5° 8.9

Use the Radar Plotting Sheet to work out the below:

Find

(a) The initial CPA, TCPA, Course and speed of the target, Aspect at 0942;

(b) The Captain of own ship decides to let the target pass ahead with a CPA

of 1.5' by taking a single action (i.e. an alteration of course or speed) at 0945;

Plot the 3 possible actions (A/Co to Stbd., A/Co to Port, Alter speed) open to

him;

Which of them is most preferable according to COLREGs? Give reasons.



Exercise 4 SIMULATOR EXERCISE (4 Hours)

Operation of ARPA or radar target tracking (TT) and AIS reporting functions

The trainee sets up and operates specific functions on the ARPA.

Demonstrate the following tasks on ARPA while navigating safely in a Coastal sea

with few target:

Switch “On” ARPA and Tune ARPA to Exercise scenario settings;


Sets Guard Zones for Auto acquisition of targets;

Import Route or Plan a Route of 2 or 3 waypoints;

Use Nav Lines Function on ARPA (where required).

Instructor must now Start Exercise

Fix Position on Chart using ARPA Ranges/Bearings;




Manually acquires the targets (ARPA/UAIS) and determines dangerous targets

(Report to Instructor when asked to identify the dangerous targets on his

screen);

Uses Trial Manoeuvre Function to decide evasive action from dangerous

targets;

Uses Range scales effectively;

Recognizes all alarms shown;

Uses additional functions available on ARPA (Predictor / SAR etc).








Expected outcomes:

Familiarize with the setting up and use of ARPA functions;

Navigate with ARPA;

Monitors vessel on Route.



Ex.5 SIMULATOR EXERCISE (4 Hours)

Application of the COLREGs when using radar

The trainee sets up and operates specific functions on the ARPA.

Demonstrate the following tasks on ARPA while navigating safely in a Coastal sea

with targets:

Switch “On” ARPA and Tune ARPA to Exercise scenario settings;


Sets Guard Zones for Auto acquisition of targets;

Import Route or Plan a Route of 2 or 3 waypoints.

Instructor must now Start Exercise

Fix Position on Chart using ARPA Ranges/Bearings;




Manually acquires the targets (ARPA / UAIS) and determines dangerous

targets (Report to Instructor when asked to identify the dangerous targets on

his screen);

Uses Trial Manoeuvre Function to decide evasive action from dangerous

targets;

Takes effective early action as per COLREGs;

Uses Range scales effectively;

Recognizes all alarms shown.








Expected outcomes:

Familiarize with the setting up and use of ARPA functions;

Navigate with ARPA;

Monitors vessel on Route;

Takes evasive action as per COLREGs.



Part E: Evaluation and Assessment

Introduction

The effectiveness of any evaluation and assessment depends to a great

extent on the precision of the description of what is to be evaluated. The

evaluation and assessment is a way of finding out if learning has taken place.

It enables the instructor to ascertain if the trainee has gained the required

skills and knowledge needed at a given point towards a course or

qualification.

Evaluation and assessment is one of the important elements for continuous

improvement of teaching quality. It not only assists the trainees to acquire

competence capability, but also helps the instructor find any issue which may

happen during teaching and keep improving curriculum programmes.

The purpose of evaluation and assessment is to:

assist trainee learning;

identify trainees' strengths and weaknesses;

appraise trainees' ability to maintain safe navigation by using radar

and ARPA;

assess the effectiveness of a particular instructional strategy;

assess and improve the effectiveness of curriculum programmes;

assess and improve teaching effectiveness;

provide feedbacks to instructors on trainee's learning;

evaluate a module's strengths and weaknesses.

Part E provides the instructor with principles to choose the methods of

evaluation and assessment, the types of evaluation and assessment, some

examples of tests requiring the selection of correct or best responses from

given alternatives, the supplies of short answers or the supplies of more

extensive written responses to prepared questions. The examples are

compiled as per requirements of sections of A-II/1 and B-I/12 in STCW.

Types of assessment

Assessments can be classified into three types.

Initial/Diagnostic assessment

This should take place before the trainee commences a course/qualification

to ensure he/she is on the right path. Diagnostic assessment is an

assessment of a trainee's skills, knowledge, strength and areas for



development. This can be carried out during an individual or group setting by

the use of relevant tests.

Formative assessment

It is an integral part of the teaching/learning process and is therefore a

"continuous" assessment. It provides information on the trainee's progress

and may also be used to encourage and motivate them. The purpose of

formative assessment is to provide feedbacks to trainees, to motivate

trainees, to diagnose trainees' strengths and weaknesses and to help

trainees to develop self-awareness.

Summative assessment

It is designed to measure the trainee's achievement against defined

objectives and targets. It may take the form of an examination or an

assignment. In the course, individual summative assessments are assigned

and can be interspersed as appropriate throughout the course.

As an integral part of the process, all have to be individually passed. Other

examinations, including a "final examination" may be added at the discretion

of the instructor, but they cannot replace or offset any required assessment

not passed by the trainee.

The purpose of summative assessment is to decide whether a trainee is to

pass or fail or to grade a trainee.

Methods of assessment

Assessment planning should be specific, measurable, achievable, realistic

and time-bound (SMART).

The methods chosen to carry out an assessment will depend upon what the

trainee is expected to achieve in terms of knowledge, understanding and

proficiency of the course content.

The methods used can range from a simple question-and-answer discussion

with the trainees (either individually or as a group) to prepared tests requiring

the selection of correct or best responses from given alternatives, the correct

matching of given items, the supply of short answers or the supply of more

extensive written responses to prepared questions.

Some methods of assessment that could be used depending upon the

course/qualification are as follows and should all be adapted to suit individual

needs:

Observation (In Oral examination, Simulation exercises, Practical

demonstration);

Questions (written or oral);

Tests;



Assignments, activities, projects, tasks and/or case studies;

Simulations (also refer to section A-I/12 of the STCW code 2010);

CBT.

All work assessed should be valid, authentic, current, sufficient and reliable;

this is often known as VACSR, "Valid assessment create standard results".

Valid, the work is relevant to the standards/criteria being assessed;

Authentic, the work has been produced solely by the trainee;

Current, the work is still relevant at the time of assessment;

Sufficient, the work covers all the standards/criteria; and

Reliable, the work is consistent across all trainees, over time and at

the required level.

It is important to note that no single method can satisfactorily measure

knowledge and skill over the entire spectrum of matters to be tested for the

assessment of competence.

Care should therefore be taken to select the most appropriate method for the

particular aspect of competence to be tested, bearing in mind the need to

frame questions which relate as realistically as possible to the requirements

of the officer's job at sea.

Evaluation of competence

The arrangements for evaluating competence should be designed to take

account of different methods of evaluation which can provide different types

of evidence about trainees' competence, e.g.:

direct observation of work activities (including seagoing service);

skills/proficiency/competency tests;

projects and assignments;

evidence from previous experience; and

written, oral and computer-based questioning techniques.

One or more of the first four methods listed should almost invariably be used

to provide evidence of ability, in addition to appropriate questioning

techniques to provide evidence of supporting knowledge and understanding.

The assessment techniques in Part D can be regarded as the reference for

evaluating the competence of a trainee. It is worth noting that the

competence evaluation standards given in Part A of the STCW Code should

be used when performing the evaluation programme.



Assessment description

(1) Quality of test items

No matter what type of test is adopted, questions or test items should be as

brief as possible, since the time taken to read the questions themselves

lengthen the examination. Furthermore, the form of the questions must be

clear and complete. To ensure these, the paper needs to be revised by

another person rather than the originator. No extraneous information should

be incorporated into the paper; such inclusions can waste the time of the

candidates and tend to be regarded as "trick questions". In all cases, the

questions should be checked repeatedly to ensure that they can assess the

trainees objectively by which is essential to the concerning competences.

Tests for assessment include practical training test, written or oral test and

multiple choice test, etc.

Advantages and disadvantages will occur in all kinds of evaluation and

assessments. Competent authorities of the evaluation should analyse

effectively the aim of the test and the expected result. A careful selection of

the test and evaluation methods should then be made and the advanced

method of testing should be employed. Each test shall be fit for testing the

learning outcomes or abilities of the trainees.

(2) Practical training test

Some aspects of competency can only be properly assessed by having the

candidate demonstrate their ability to perform specific tasks in a safe and

efficient manner. This can prove to be an issue that would affect the safety

the ship and the protection of the marine environment. This can be

accomplished in a safer environment by incorporating the use of shoreside

live radar or simulators.

This equipment must be capable of adequately assessing the competencies

and KUPs being tested. When economically feasible, this equipment can be

dedicated solely for assessments or examinations.

(3) Written or oral test

In general, written or oral tests are excellent forms to evaluate trainees'

knowledge, understanding and proficiency of the KUPs. However, if the goal

is to evaluate a broad spectrum of material using only a sample of questions,

care must be taken to protect the security of the examination from the

trainees prior to the examination period. It is only natural for the trainees to

focus on just the sample questions and not the broad spectrum of the

material if the trainees have access to an examination prior to the

examination period. Therefore, instructors should adjust the questions and

format of their exams at reasonable periods of time.



(4) Multiple choice questions

Marking or scoring is easier if multiple-choice test items are used, but in

some cases difficulties may arise in creating plausible distracters.

Detailed sampling allows immediate identification of errors of principle and

those of a clerical nature. It must be emphasized that this holds true, in

general, only if the test item is based on a single step in the overall

calculation. Multiple-choice items involving more than one step may, in some

cases, have to be resorted to in order to allow the creation of a sufficient

number of plausible distracters, but care must be exercised to ensure that

distracters are not plausible for more than one reason if the nature of the

error made (and hence the distracter chosen) is to affect the scoring of the

test item.

Distracters

The incorrect alternatives in multiple-choice questions are called "distracters",

because their purpose is to distract the uninformed trainee from the correct

response. The distracter must be realistic and should be based on

misconceptions commonly held, or on mistakes commonly made.

The options "none of the above" or "all of the above" are used in some tests.

These can be helpful, but should be used sparingly.

Distracters should distract the uninformed, but they should not take the form

of "trick" questions that could mislead the knowledgeable trainee (for

example, do not insert "not" into a correct response to make it a distracter).

Guess factor

The "guess factor" with four alternative responses in a multiple-choice test

would be 25%. The pass mark chosen for all selective-response questions

should take this into account.

Scoring

In simple scoring of objective tests one mark may be allotted to each correct

response and zero for an incorrect or nil response.

A more sophisticated scoring technique entails awarding one mark for a

correct response, zero for a nil response and minus one for an incorrect

response. Where a multiple-choice test involves four alternatives, this means

that a totally uninformed guess involves a 25% chance of gaining one mark

and a 75% chance of losing one mark.

Scores can be weighted to reflect the relative importance of questions, or of

sections of an evaluation.



APPENDIX 4

An example of examination paper

Ⅰ. Multiple choices (choose the best or appropriate answer from the four options)

1． Which is not the function of a radar antenna?

A. To receive microwave pulses from the transmitter.

B. To focus transmitter pulses into beam and then send them into space.

C. To receive echo pulses coming from objects those have been struck by the

antenna beam.

D. To reflect microwave.

2． Which is not used in a modern radar?

A. EBL.

B. VRM.

C. Mechanical cursor.

D. Raster scan indicator.

3． Which typically extends from close as 0.1 nm out to 48 nm?

A. EBL.

B. VRM.

C. STC.

D. Target tracking range.

4． Although manual plotting works well for CPA, the workload can become

overwhelming when confronted with______.

A. a large number of targets

B. two targets

C. three targets

D. one target

5． PPI is the short for ______ in marine radar.

A. plan pulse indicator

B. plan point indicator

C. power pulse indicator

D. plan position indicator



6． A S band radar as compared to a X band radar of similar specifications will

______.

A. be more suitable for river and harbour navigation

B. provide better range performance on a low lying target during good weather

and calm seas

C. have a wide horizontal beam width

D. have more sea clutter during rough sea conditions

7． The correct method of switching off a marine radar is to turn power switch to

______ position first, then to______ position.

A. off; standby

B. standby; off

C. standby; ready

D. ready; standby

8． The radar control that depresses echoes from the own ship to a limited distance

is ______.

A. sensitivity time control

B. receiver gain control

C. brilliance control

D. fast time control

9． What will cause an automatic tracking radar to give a visual alarm and an

audible alarm?

A. An acquired target entering into a guard zone.

B. A tracked target lost for one radar scan.

C. CPA of a tracked target is less than the CPA LIM, TCPA more than TCPA

LIM.

D. Both CPA and TCPA of a tracked target is less than the CPA LIM and TCPA

LIM.

10． When using radar for position-fixing, the best way is ______.

A. using tangent bearing and range of one target

B. using two radar bearings

C. using ranges, the most rapidly changing range shall be measured last

D. using ranges, the most rapidly changing range shall be measured first

11． You are observing a buoy fitted with a Racon on the radar screen. How

should this target appear on the display?

A. As a broken line from centre of radar picture to the buoy target.



B. Starting with a dash and extending radially outward from the buoy target.

C. Starting with a dash and extending to the right of the buoy target.

D. Starting with a dash and extending radially inward from the buoy target.

12． Radar pulse length varies with range scales. Which of the following is

correct?

A. Short range for narrow pulse.

B. Medium range for narrow pulse.

C. Short range for long pulse.

D. Long range for narrow pulse.

13． For ______ presentation mode, when the own ship alters course or yaws

on rough sea, radar target will be unstable and the radar image will be blurring.

A. north Up, relative motion

B. north Up, true motion

C. course Up

D. head Up

14． For N-up and C-up orientation, ______ signal shall be connected.

A. EPFS

B. COG

C. GYRO

D. SOG

15． Which of the following factor has no relationship with radar maximum

detection range?

A. Radar transmitting power.

B. VBW.

C. Antenna gain.

D. Radar transmitting wavelength.

16． The main factor governing the range discrimination is ______.

A. pulse duration

B. horizontal beam width

C. p. r. f.

D. vertical beam width

17． Which of the following feature is false for the indirect false echo?

A. It appears in shadow zone.

B. The bearing of the indirect false echo is the same as the obstacle's bearing.



C. Indirect false echo is weaker than real echo.

D. The range of indirect false echo is less than the true target echo.

18． For modern radar, past position modes are determined by ______ modes.

A. true motion

B. motion

C. vector

D. relative motion

19． In order to reduce sea clutter, which of the following is false?

A. Use narrow pulse.

B. Use circular polarization antenna.

C. Use S band radar.

D. Use STC control.

20． Which of the following feature is false for radar multiple echoes?

A. Multiple echoes and true echoes can be reduced by STC control equally.

B. It appears in the direction of real echo continuously with the same range

interval.

C. The range interval of each multiple echo is equal to real echo range.

D. Multiple echoes are further; and the further the echo, the weaker the echo.

21． When a radar is used for navigation purpose, which of the following

sensors should be connected with the radar?

A. A gyrocompass, a speed log.

B. A gyrocompass, a speed log, an EPFS.

C. A gyrocompass, a speed log, an EPFS, an echo sounder.

D. A gyrocompass, a SDME, an AIS, an EPFS.

22． Which of the following statements is a right selection order for radar manual

acquisition?

A. Bow, starboard, long range.

B. Bow, port, nearby.

C. Bow, starboard, nearby.

D. Bow, nearby, port.

23． In order to reduce rain clutter, which of the following operation is incorrect?


B. Use STC control.




D. Use a circular polarization antenna.

24． According to the latest radar performance standards, if automatic

anti-clutter processing could prevent the detection of targets in the absence of

appropriate stabilization, the processing should switch off automatically______

after the azimuth stabilization has become ineffective?

A. Within 1 minute.

B. Within 2 minutes.

C. Within 3 minutes.

D. Within 4 minutes.

25． Which of the following statements is false for relative vector (RV)?

A. No relative vector for the own ship.

B. Fixed targets or other moving targets (except for the target which has the

same speed and course with the own ship) have RV.

C. RV can be used to find CPA/TCPA usually.

D. The accuracy of RV is less than TV.

26． When a radar is used for collision avoidance purpose, which of the following

sensors should be connected with the radar?

A. A gyrocompass, a speed log.

B. A gyrocompass, a speed log, an AIS transponder, an EPFS.

C. A gyrocompass, a speed log, an EPFS, an echo sounder.

D. A gyrocompass, a SDME, an EPFS.

27． Which one has nothing to do with automatic acquisition function?

A. Guard zone.

B. Dangerous zone.

C. Exclusion zone.

D. Acquisition zone.

28． In order to reduce sea clutter, which of the following is incorrect?

A. Use STC control.

B. Use narrow pulse.


D. Use echo stretch.

29． If there is an error from gyrocompass when a target is being tracked, which

data of the target cannot be affected?

A. CPA.

B. Course.



C. Speed.

D. TV.

30． Which of the following statements is true for true vector (TV)?

A. TV can be used to assess the encounter situations usually.

B. No true vector for the own ship.

C. TV can be used to find CPA/TCPA usually.

D. The accuracy of TV is better than the accuracy of RV.

31． You are observing the radar screen for a SART. How should this echo

appear on the display?

A. 8 spots and extending about 12 nm.

B. An echo with Morse code.

C. 12 spots and extending about 8 nm.

D. An echo without Morse code.

32． The pulse repetition frequency varies with range scales. Which of the

following descriptions is correct?

A. Medium range for high PRF.

B. Short range for low PRF.

C. Short range for high PRF.

D. Long range for high PRF.

33． For ______ presentation mode, the radar picture orientation is consistent

with the navigational chart and the own ship is always fixed on the screen and

the echo of an island moves on the screen.

A. north Up, true motion

B. north Up, relative motion

C. course Up, relative motion

D. head Up, true motion

34． Usually, C-up presentation is used for________.

A. fixing position

B. collision avoidance

C. navigation in narrow channel

D. entering or leaving port

35． Which of the following factors has no relationship with radar minimum

detection range?

A. Radar transmitting power.



B. Pulse length.

C. Recovery time of duplexer.

D. Height of antenna.

36． The main factor governing bearing discrimination is ______.

A. HBW

B. pulse length

C. PRF

D. VBW

37． Which of the following features is true for second trace false echo?

A. It appears in shadow zone.

B. There is no distortion for second trace false echo.

C. The range of second trace false echo is same as the target's range.

D. The bearing of second trace false echo is the same as the target's bearing.

38． For a modern radar, which statement is false for trial manoeuvre?

A. Trial manoeuvre is just a simulation.

B. Delay time and dynamic characteristics should be considered.

C. The COLREGs are not considered.

D. The result can be reliable when target ships changing their course and

speed.

39． In order to reduce radar interference, which of the following is true?


B. Use S band radar.

C. Use sweep correlation.

D. Use STC control.

40． Which of the following features is false for radar side false echoes?

A. The false echoes and real echo have the same range.

B. The false echoes distribute on both sides of the real echo symmetrically.

C. The false echoes and real echo have the same bearing.

D. The strength of false echoes is weaker than the real echo's.

Ⅱ. Answer the following questions briefly

1． In which condition, the OOW may observe an indirect false echo? What are the

features of the indirect false echo? How to identify the indirect false echo？

2． Please list the image features of true motion presentation mode. If a radar can

work on the true motion mode, which sensor(s) should be connected?



3． What is the meaning of relative vector? Please list the applications of relative

vector and the cautions.

4． (1) Please name the symbols of AIS reported target.

_______________ _______________ _______________

_______________ _______________

______________

(2) What is the concept of association of AIS reported and tracked targets?

(3) Please list 5 boundary parameters that could be set for the association

criteria.

5． Please analyse the figures below and answer the following questions.

(1) Why T2 has no vector in figure (a) and (b)?

(2) Why T4 has no vector in figure (c) and (d)?

(3) Which figures are used to assess the risks of collision usually? Which target

is the dangerous one for the own ship and why?

(4) Which figures are used to assess the encounter situations usually? There

situations between the target and the own ship are crossing encounter situation

and stand-on situation in the figures. Which one?

6. Please analyse the figures below and answer the following questions.

(1) What is the name and function of the ring in figure (a)?

(2) What are the names and how many kinds of dots does the radar present in

figure (b)? What kind of dots is in figure (b)? What information can different kinds

of dots provide to the OOW?

(3) What are the names and how many kinds of line segment does radar present

in figure (b) except the HL? What kind of line segment is in figure (b)? What



information can different kinds of line segments provide to the OOW except the

HL?

(a) (b)



Appendix 5

An example of assessment for practical training

Topic 5 & 6 Operation of ARPA or TT and AIS reporting functions LESSON NUMBER: DURATION: 0.8 h

Practical training 5 & 6 -1: Operation of ARPA or TT and AIS reporting functions

Training objectives: Setting up and maintaining ARPA or TT and AIS reporting functions correctly - Setting up and checking sensors

and system parameters

Assessment elements and criteria

KUPs/Required performances Assessment methods

6. Operate ARPA or TT and AIS reporting

functions/Set up and maintain ARPA or TT and

AIS reporting functions correctly,

- Set up and check sensor and system

parameters

Assessment elements Assessment criteria

(1) check OS (the own ship) course Comparison of the radar heading with the

gyrocompass

The radar heading is consistent with the indication of the gyrocompass and

follow-up smoothly, Otherwise make corrections according to the

manufacturers' manual.



(2) check OS speed Selection of STW/SOG STW is selected and the speed indication is the same with the speed-log.

Otherwise make corrections according to the manufacturers' manual.

(3) check OS position Comparison of the position data on radar

display with the EPFS position

The position data on radar display is consistent with that of EPFS and the

integrity information of EPFS is confirmed.

(4) set up CPATCPA Limits Set-up at open sea, coastal or congested

waters

Reasonable setting according to navigational situations

(5) Setting up and maintaining displays the correct starting procedure to obtain the

optimum display of ARPA information;

Ability to demonstrate:

1. the selection of display presentation; stabilized relative-motion

displays and true-motion displays;

2. the correct adjustment of all variable radar display controls for

optimum display of data;

3. the selection, as appropriate, of required speed input to ARPA;

4. the selection of ARPA plotting controls, manual/automatic

acquisition, vector/graphic display of data;

5. the selection of the timescale of vectors/graphics;

6. the use of exclusion areas when automatic acquisition is employed

by ARPA; and

7. performance checks of radar, compass, speed input sensors and

ARPA.

(6) System operational tests Data accuracy of ARPA Ability to perform system checks and determine data accuracy of ARPA,

including the trial manoeuvre facility, by checking against basic radar plot.

(7) Obtaining information from the ARPA Demonstrate the ability to obtain 1. the identification of critical echoes;



display information in both relative- and true-motion

modes of display

2. the speed and direction of target's relative movement;

3. the time to, and predicted range at, target's closest point of

approach;

4. the courses and speeds of targets;

5. detecting course and speed changes of targets and the limitations

of such information;

6. the effect of changes in own ship's course or speed or both; and

7. the operation of the trial manoeuvre facility.

(8) Possible risks of over-reliance on ARPA .Appreciation that ARPA is only a

navigational aid

ARPA has its limitations, including those of its sensors, make over-reliance

on ARPA dangerous

(9) Demonstrate the proper use AIS Set up and use in accordance with

manufacturers' instructions and

AIS target interpretation

Interpreting and using the information generated by shipboard AIS in relation

to:

1. displayed data

2. identification of vessels

3. target tracking

4. maintaining situation awareness

5. dynamic information

6. voyage related information

7. reception and transmission of safety related messages

8. manual input of data, data updating and checking data



Appendix 6

Sample checklist for evaluation of proficiency in the use

of Radar and ARPA

S.No. Tasks

1 Demonstrate understanding of radar (Solid state/magnetron) configuration,

including:

antenna;

o Siting (Vertical clearance, Visibility criteria, no obstructions)

o Conning position offset (if located away)

Transceiver unit;

Performance monitor;

Display system;

o Magnetic compass safe distance

o Display screen size min requirement as per IMO PS

T/R switch (cell);

Power supply (Main and Emergency);

Inter switch; and

Radar type (X band or S band).

2 Identify all Sensor inputs to Radar/ARP:

Gyro compass or THD;

SDME or Dual axis speed log;

EPFS;

AIS;

Track control unit (if fitted); and

Anemometer, Echo sounder etc.(if fitted).

3 Identify all Sensor outputs from Radar/ARPA:

VDR;

ECDIS; and

Remote Display, etc. (if fitted).

4 Location of the Radar/ARPA spares onboard(Magnetron, CRT or LCD/Raster

scan television tubes, etc.)

5 Identify the Warning tags to be placed on the Radar for any maintenance on

the Radar and Main breaker location



6 Identify all the Operational panel buttons/keyboard/joystick/trackball/Night

screen hood

7 Demonstrate starting procedure of Radar:

Check Scanner clear;

Standby/ON(Tx);

Sea clutter (STC) and Rain clutter (FTC) settings (Manual/Auto);

Brilliance and Gain settings;

Enhance Video control (if fitted);

o Echo average / Echo stretch /Interference Rejector

Tuning settings (Manual/AFC);

Radar Transmission Pulse length settings (SP/MP/LP);

Display Screen Day or Night selection settings;

Degauss function (if available); and

Panel brilliance settings.

8 Select Radar/ARPA range scales

Enable/Disable fixed Range rings

9 Select Mode of Display:

Sea stabilized; and

Ground stabilized.

10 Set orientation of Main display:

North up;

Head up; and

Course up.

11 Set motion of Main display:

True Motion (TM); and

Relative Motion (RM).

12 Locate Heading Line / Stern line (if fitted):

Set Heading line on/off.

13 Locate Cursor:

Set Display to Toggle between Range and Brg / Lat and Long.

14 Off centring the Picture:

Centring the Offset picture.

15 Locate ship's heading and Speed:

Align the heading (if required);

Speed mode Log/EPFS/Manual (STW/SOG); and



Applying Set and Drift in STW mode.

16 Locate Ship's Position and Time on display screen

17 Set EBL and VRM (On/Off):

EBL1 and EBL2;

VRM1 and VRM2;

Offset; and

Determine Visibility.

18 Set CPA and TCPA alarm limits:

Understand ARPA Limitations.

19 Manual acquisition of targets:

Acquire/cancel;

Data (Target Identification/Name, Range, Bearing, STW/SOG,

CSE/CMG,CPA, TCPA, BCR, BCT);

Target Alarm Symbols (Lost Ref, Bow Crossing, CPA/TCPA, AZ Entry,

Lost Target);

Maximum number of Targets available;

Radar beacons (as per NP5011);

SART transponder;

Factors which effect the echo strength from targets; and

False echoes.

20 Setting Guard Zones (On/Off):

Guard Zone 1; and

Guard Zone 2.

21 Automatic acquisition of targets:

Acquire / cancel.

22 Set Trial Manoeuvre:

Set new Course/Speed/Time delay.

23 Display of UAIS Targets (if UAIS transponder connected):

Differentiate between Sleeping / Active targets;

Target symbols shown;

Additional UAIS data (MMSI, Heading, Navigational status,

Ship type, IMO number, Call sign, Ship name, port of

destination); and

AIS and Radar target association.

24 Selecting Vector mode:



True Vectors;

Relative Vectors; and

Selecting a Vector time.

25 Selecting the Trails mode:

True Trails;

Relative Trails; and

Selecting Trails time (Short / Long/ Perm / Off / Reset).

26 Select Parallel Index Lines:

Edit Index Lines 1, 2, 3…

27 Setting a Mark (s) (On / Off)

28 Differentiate various alarms:

Set Buzzer On/Off; and

Select Anchor watch alarm (if fitted).

29 Setting Routes (On/Off)

30 Select and Edit Maps (if fitted):

Nav Lines;

Nav marks; and

Verifying Maps.

31 Use optional functions (if available):

Wind Speed and direction (True/Rel);

Depth;

SAR routes; and

Chart underlay.

32 View Blind/Shadow Sectors:

Prepare Blind/Shadow sector Card.

33 Performance Monitor checks (transmitter/receiver performance):

Diagnostic test (if available) (checks major circuit boards in radar display unit).

34 Radar Log book entries



Radar Plotting/Simulation Evaluation Proficiency Checklist

Trainee A B C D E F G H I J K L

Bridge

Radar Plotting / Simulation Evaluation

Task (see following pages for details)

1 Relative Radar Plotting

To Find CPA, TCPA, Course, Speed

and aspect of target

2 Relative Radar Plotting (Action taken by

target)

To Find new CPA, TCPA, Course,

Speed and aspect of target

3 Relative Radar Plotting (Action taken by

Own ship)

To Find new CPA, TCPA, Course,


4 Relative Radar Plotting (Pass at desired

CPA)

To predict action to take by Own ship to

5 True Radar Plotting

To Find CPA, TCPA, Course, Speed

and aspect of target;

Action taken by target;

o To Find new CPA, TCPA, Course,


Action taken by Own ship; and

o To Find new CPA, TCPA, Course,


To pass at desired CPA;

o To predict action to take by Own ship.

6 Switching on Radar/ARPA correctly

Check that setting conform to

procedures (briefing)

7 Understand the various

Stabilized modes, Orientations, Vectors

and trails



8 Manage targets (Radar/AIS)

9 Adjust settings to suit conditions and

adapt to changing conditions

10 Manoeuvre according to accepted

navigational practice and with regard to

COLREGS

Score each task 3, 2, or 1 according to Evaluation Methods listed below.

Max score = 30 pts. Minimum passing score = 21 pts (70%).

TRAINEE SCORES

Trainee name/ID Score Trainee name/ID Score

A G

B H

C I

D J

E K

F L

NOTES:

Methods for evaluating competence:

Assessment of evidence obtained from Radar Plotting sheet exercises and approved Radar/ARPA

simulator training in underway scenarios utilizing ship control, visual scene and sensors providing

integrated input to Radar/ARPA including radar, target tracking, positioning, and AIS (See also STCW

B-I/12, Guidance regarding the use of simulators, and B-II/1 and BII/2, Guidance regarding the

certification of officers.).

Criteria for evaluating competence:

Information obtained from Radar/ARPA is correctly interpreted and analysed taking into account the

limitations of the equipment and prevailing circumstances and conditions.

1) Relative Radar Plotting (to Find CPA, TCPA, Course, Speed and aspect of target) [No

error = 3; uses some error = 2; error = 1]

.1 Determines the CPA, TCPA, Course, Speed and aspect of target.



2) Relative Radar Plotting (Action taken by target : to Find new CPA, TCPA, Course, Speed

and aspect of target) [No error = 3; uses some error = 2; error = 1]

.1 Determines the new CPA, TCPA, Course, Speed and aspect of target.

3) Relative Radar Plotting (Action taken by Own Ship : to Find new CPA, TCPA, Course,

Speed and aspect of target) [No error = 3; uses some error = 2; error = 1]

.1 Determines the new CPA, TCPA, Course, Speed and aspect of target.

4) Relative Radar Plotting (To predict action to take by Own ship to pass at desired CPA) [No

error = 3; uses some error = 2; error = 1]

.1 Determines the new correct action to take (Course change/speed change) to pass at the desired

CPA.

5) True Radar Plotting (to Find CPA, TCPA, Course, Speed and aspect of target, Action

taken by target, Action taken by Own ship, To predict action to take by Own ship to pass

at desired CPA) [No error = 3; uses some error = 2; error = 1]

.1 Determines the CPA, TCPA, Course, Speed and aspect of target; or

.2 Determines the new CPA, TCPA, Course, Speed and aspect of target, after Action taken by

target; or

.3 Determines the new CPA, TCPA, Course, Speed and aspect of target, after Action taken by Own

ship; or

.4 Determines the new correct action to take (Course change / speed change) to pass at the desired

CPA.

6) Switching on Radar/ARPA correctly [Adjusts most/all = 3; adjusts some = 2; adjusts none

= 1]

.1 Adjust the following settings and values on Radar/ARPA to suit the present conditions:

a. Pre start checks explained correctly;

b. Time of Standby to transmit known;

c. Gain, Brilliance, Tuning, Sea & Rain Clutter;

d. Choice of S-band or X-band Radar/ARPA known; and

e. Setting Guard zones for auto acquisition.

7) Understand the various Stabilized modes, Orientations, Vectors and trails [Effective use

= 3; some use = 2; no use = 1]

a. Sea/Ground stabilized mode;

b. North up/Head up/Course up display orientation;

c. True/Relative vectors;

d. Trails;



e. Range scales used; and

f. Off centre used.

8) Manage targets (Radar/AIS) [Effective target management= 3; some inefficiencies in

target management = 2; unsafe/no target management = 1]

.1 Identify all targets on Radar/ARPA;

.2 Monitor dangerous targets;

.3 Determine dangerous targets CPA/TCPA correctly;

.4 Handles lost targets alarms; and

.5 Plots positions using suitable targets.

9) Adjust settings to suit conditions and adapt to changing conditions [Effective use of

available functionality = 3; some sue of available functionality = 2; no use of available

functionality = 1]

.1 Changes radar scales as per situation (advance warning, traffic density, small vessels) & assess

visibility;

.2 Uses relative vectors to determine Risk of collision;

.3 Uses true trails to note vessels COG;

.4 Adjusts sea/rain clutter as per present environment;

.5 Uses parallel indexing effectively as required; and

.6 Sets CPA/TCPA alarms correctly.

10) Manoeuvre according to accepted navigational practice and with regard to COLREGS

[Effective manoeuvres = 3; some inefficiencies in manoeuvres = 2; unsafe manoeuvres =

1]

.1 Decisions to amend course and/or speed are both timely and in accordance with accepted

navigation practice; and

.2 Use trial manoeuvre function for manoeuvre planning; use CPA/TCPA alarms on ARPA; apply

COLREGS; observe transit restrictions for given port.



Annex 1

Resolution MSC. 192(79) (Adopted on 6 December 2004)

THE MARITIME SAFETY COMMITTEE,

RECALLING Article 28(b) of the Convention on the International

Maritime Organization concerning the functions of the Committee,

RECALLING ALSO resolution A. 886(21) by which the Assembly

resolved that the functions of adopting performance standards and technical

specifications, as well as amendments thereto, shall be performed by the

Maritime Safety Committee on behalf of the Organization,

NOTING resolutions A. 222(VII), A. 278(VIII), A. 477(XII), MSC. 64(67),

annex 4, A. 820(19) and A. 823(19) containing performance standards

applicable to marine radars being produced and installed at different time

periods in the past,

NOTING ALSO that marine radars are used in connection/integration

with other navigational equipment required to carry on board ships such as, an

automatic target tracking aid, ARPA, AIS, ECDIS and others,

RECOGNIZING the need for unification of maritime radar standards in

general, and, inparticular, for display and presentation of navigation-related

information,

HAVING CONSIDERED the recommendation on the revised

performance standards for radar equipment made by the Sub-Committee on

Safety of Navigation at its fiftieth session,

1. ADOPTS the Revised Recommendation on Performance Standards for

radar equipment set out in the Annex to the present resolution;

2. RECOMMENDS Governments to ensure that radar equipment installed on

or after1 July 2008 conform to performance standards not inferior to those

set out in the Annex to the present resolution.

Revised Recommendation on Performance Standards for

Radar Equipment

INDEX

1 SCOPE OF EQUIPMENT

2 APPLICATION OF THESE STANDARDS



3 REFERENCES

4 DEFINITIONS

5 OPERATIONAL REQUIREMENTS FOR THE RADAR SYSTEM

6 ERGONOMIC CRITERIA

7 DESIGN AND INSTALLATION

8 INTERFACING

9 BACKUP AND FALLBACK ARRANGEMENTS

1 SCOPE OF EQUIPMENT

The radar equipment should assist in safe navigation and in avoiding collision

by providing an indication, in relation to own ship, of the position of other

surface craft, obstructions and hazards, navigation objects and shorelines.

For this purpose, radar should provide the integration and display of radar

video, target tracking information, positional data derived from own ship's

position (EPFS) and geo referenced data. The integration and display of AIS

information should be provided to complement radar. The capability of

displaying selected parts of Electronic Navigation Charts and other vector

chart information may be provided to aid navigation and for position

monitoring.

The radar, combined with other sensor or reported information (e.g. AIS),

should improve the safety of navigation by assisting in the efficient navigation

of ships and protection of the environment by satisfying the following functional

requirements:

in coastal navigation and harbour approaches, by giving a clear

indication of land and other fixed hazards;

as a means to provide an enhanced traffic image and improved

situation awareness;

in a ship-to-ship mode for aiding collision avoidance of both detected

and reported hazards;

in the detection of small floating and fixed hazards, for collision

avoidance and the safety of own ship; and

in the detection of floating and fixed aids to navigation (see Table 2,

note 3).

2 APPLICATION OF THESE STANDARDS

These Performance Standards should apply to all shipborne radar installations,

used in any configuration, mandated by the 1974 SOLAS Convention, as

amended, independent of the

type of ship;



frequency band in use; and

type of display,

providing that no special requirements are specified in Table 1 and that additional

requirements for specific classes of ships (in accordance with SOLAS chapters V and

X) are met.

The radar installation, in addition to meeting the general requirements as set out in

Resolution A. 694 (17), should comply with the following performance standards.

Close interaction between different navigational equipment and systems, makes it

essential to consider these standards in association with other relevant IMO

standards.

TABLE 1

Differences in the performance requirements for

Various sizes/categories of ship/craft to which SOLAS applies

Size of ship/craft <500 gt 500 gt to <10,000 gt

and HSC<10,000 gt

All ships/craft

=10,000 gt

Minimum operational display area diameter 180 mm 250 mm 320 mm

Minimum display area 195 x 195 mm 270 x 270 mm 340 x 340 mm

Auto acquisition of targets - - Yes

Minimum acquired radar target capacity 20 30 40

Minimum activated AIS target capacity 20 30 40

Minimum sleeping AIS target capacity 100 150 200

Trial Manoeuvre - - Yes

3 REFERENCES

References are in appendix 1.

4 DEFINITIONS

Definitions are in appendix 2.

5 OPERATIONAL REQUIREMENTS FOR THE RADAR SYSTEM

The design and performance of the radar should be based on user requirements and

up-to-date navigational technology. It should provide effective target detection within

the safety-relevant environment surrounding own ship and should permit fast and

easy situation evaluation.

5.1 Frequency

5.1.1 Frequency spectrum

The radar should transmit within the confines of the ITU allocated bands for maritime

radar and meet the requirements of the radio regulations and applicable ITU-R

recommendations.

5.1.2 Radar Sensor Requirements



Radar systems of both X and S-Bands are covered in these performance standards:

X-Band (9.2-9.5 GHz) for high discrimination, good sensitivity and tracking

performance; and

S-Band (2.9-3.1 GHz) to ensure that target detection and tracking capabilities

are maintained in varying and adverse conditions of fog, rain and sea clutter.

The frequency band in use should be indicated.

5.1.3 Interference susceptibility

The radar should be capable of operating satisfactorily in typical interference

conditions.

5.2 Radar Range and Bearing Accuracy

The radar system range and bearing accuracy requirements should be:

Range - within 30 m or 1% of the range scale in use, whichever is greater;

Bearing - within 1°.

5.3 Detection Performance and Anti-clutter Functions

All available means for the detection of targets should be used.

5.3.1 Detection

5.3.1.1 Detection in Clear Conditions

In the absence of clutter, for long range target and shoreline detection, the

requirement for the radar system is based on normal propagation conditions, in the

absence of sea clutter, precipitation and evaporation duct, with an antenna height of

15 m above sea level.

Based on:

an indication of the target in at least 8 out of 10 scans or equivalent; and

a probability of a radar detection false alarm of 10-4,

The requirement contained in Table 2 should be met as specified for X-Band and

S-Band equipment.

The detection performance should be achieved using the smallest antenna that is

supplied with the radar system.

Recognizing the high relative speeds possible between own ship and target, the

equipment should be specified and approved as being suitable for classes of ship

having normal (<30 kn) or high (>30 kn) own ship speeds (100 kn and 140 kn relative

speeds respectively).



TABLE 2

Minimum detection ranges in clutter-free conditions

Target Description Target Feature Detection Range in nm

Target description Height above sea

level in meters

X-Band

nm

S-Band

nm

Shorelines Rising to 60 20 20



SOLAS ships (>5000 gross tonnage) 10 11 11

SOLAS ships (>500 gross tonnage) 5.0 8 8

Small vessel with radar reflector meeting IMO

Performance Standards 4.0 5.0 3.7

Navigation buoy with corner reflector 3.5 4.9 3.6

Typical Navigation buoy 3.5 4.6 3.0

Small vessel of length 10 m with no radar reflector 2.0 3.4 3.0

5.3.1.2 Detection at Close Range

The short-range detection of the targets under the conditions specified in Table 2

should be compatible with the requirement in paragraph 5.4.

5.3.1.3 Detection in Clutter Conditions

Performance limitations caused by typical precipitation and sea clutter conditions will

result in a reduction of target detection capabilities relative to those defined in 5.3.1.1

and Table 2.

5.3.1.3.1 The radar equipment should be designed to provide the optimum and most

consistent detection performance, restricted only by the physical limits of propagation.

5.3.1.3.2 The radar system should provide the means to enhance the visibility of

targets in adverse clutter conditions at close range.

5.3.1.3.3 Degradation of detection performance (related to the figures in Table 2) at

various ranges and target speeds under the following conditions, should be clearly

stated in the user manual:

light rain (4 mm per hour) and heavy rain (16 mm per hour);

sea state 2 and sea state 5; and

and a combination of these.

5.3.1.3.4 The determination of performance in clutter and specifically, range of first

detection, as defined in the clutter environment in 5.3.1.3.3, should be tested and

assessed against a benchmark target, as specified in the Test Standard.

5.3.1.3.5 Degradation in performance due to a long transmission line, antenna height

or any other factors should be clearly stated in the user manual.



5.3.2 Gain and Anti-Clutter Functions

5.3.2.1 Means should be provided, as far as is possible, for the adequate reduction of

unwanted echoes, including sea clutter, rain and other forms of precipitation, clouds,

sandstorms and interference from other radars.

5.3.2.2 A gain control function should be provided to set the system gain or signal

threshold level.

5.3.2.3 Effective manual and automatic anti-clutter functions should be provided.

5.3.2.4 A combination of automatic and manual anti-clutter functions is permitted.

5.3.2.5 There should be a clear and permanent indication of the status and level for

gain and all anti-clutter control functions.

5.3.3 Signal Processing

5.3.3.1 Means should be available to enhance target presentation on the display.

5.3.3.2 The effective picture update period should be adequate, with minimum latency

to ensure that the target detection requirements are met.

5.3.3.3 The picture should be updated in a smooth and continuous manner.

5.3.3.4 The equipment manual should explain the basic concept, features and

limitations of any signal processing.

5.3.4 Operation with SARTs and Radar Beacons

5.3.4.1 The X-Band radar system should be capable of detecting radar beacons in the

relevant frequency band.

5.3.4.2 The X-Band radar system should be capable of detecting SARTs and radar

target enhancers.

5.3.4.3 It should be possible to switch off those signal processing functions, including

polarization modes, which might prevent an X-Band radar beacon or SARTs from

being detected and displayed. The status should be indicated.

5.4 Minimum Range

5.4.1 With own ship at zero speed, an antenna height of 15 m above the sea level

and in calm conditions, the navigational buoy in Table 2 should be detected at a

minimum horizontal range of 40 m from the antenna position and up to a range of 1

nm, without changing the setting of control functions other than the range scale

selector.

5.4.2 Compensation for any range error should be automatically applied for each

selected antenna, where multiple antennas are installed.

5.5 Discrimination

Range and bearing discrimination should be measured in calm conditions, on a range

scale of 1.5 nm or less and at between 50% and 100% of the range scale selected:



5.5.1 Range

The radar system should be capable of displaying two point targets on the same

bearing, separated by 40 m in range, as two distinct objects.

5.5.2 Bearing

The radar system should be capable of displaying two point targets at the same range,

separated by 2.5° in bearing, as two distinct objects.

5.6 Roll and Pitch

The target detection performance of the equipment should not be substantially

impaired when own ship is rolling or pitching up to +/-10°.

5.7 Radar Performance Optimization and Tuning

5.7.1 Means should be available to ensure that the radar system is operating at the

best performance. Where applicable to the radar technology, manual tuning should be

provided and additionally, automatic tuning may be provided.

5.7.2 An indication should be provided, in the absence of targets, to ensure that the

system is operating at the optimum performance.

5.7.3 Means should be available (automatically or by manual operation) and while

the equipment is operational, to determine a significant drop in system performance

relative to a calibrated standard established at the time of installation.

5.8 Radar Availability

The radar equipment should be fully operational (RUN status) within 4 minutes after

switch ON from cold. A STANDBY condition should be provided, in which there is no

operational radar transmission. The radar should be fully operational within 5 sec from

the standby condition.

5.9 Radar Measurements – Consistent Common Reference Point (CCRP)

5.9.1 Measurements from own ship (e.g. range rings, target range and bearing,

cursor, tracking data) should be made with respect to the consistent common

reference point (e.g. conning position). Facilities should be provided to compensate

for the offset between antenna position and the consistent common reference point on

installation. Where multiple antennas are installed, there should be provision for

applying different position offsets for each antenna in the radar system. The offsets

should be applied automatically when any radar sensor is selected.

5.9.2 Own ship's scaled outline should be available on appropriate range scales.

The consistent common reference point and the position of the selected radar

antenna should be indicated on this graphic.

5.9.3 When the picture is centred, the position of the Consistent Common

Reference Point should be at the centre of the bearing scale. The off-centre limits

should apply to the position of the selected antenna.



5.9.4 Range measurements should be in nautical miles (nm). In addition, facilities

for metric measurements may be provided on lower range scales. All indicated values

for range measurement should be unambiguous.

5.9.5 Radar targets should be displayed on a linear range scale and without a

range index delay.

5.10 Display Range Scales

5.10.1 Range scales of 0.25, 0.5, 0.75, 1.5, 3, 6, 12 and 24 nm should be provided.

Additional range scales are permitted outside the mandatory set. Low metric range

scales may be offered in addition to the mandatory set.

5.10.2 The range scale selected should be permanently indicated.

5.11 Fixed Range Rings

5.11.1 An appropriate number of equally spaced range rings should be provided for

the range scale selected. When displayed, the range ring scale should be indicated.

5.11.2 The system accuracy of fixed range rings should be within 1% of the

maximum range of the range scale in use or 30 m, whichever is the greater distance.

5.12 Variable Range Markers (VRM)

5.12.1 At least two variable range markers (VRMs) should be provided. Each active

VRM should have a numerical readout and have a resolution compatible with the

range scale in use.

5.12.2 The VRMs should enable the user to measure the range of an object within

the operational display area with a maximum system error of 1% of the range scale in

use or 30 m, whichever is the greater distance.

5.13 Bearing Scale

5.13.1 A bearing scale around the periphery of the operational display area should

be provided. The bearing scale should indicate the bearing as seen from the

consistent common reference point.

5.13.2 The bearing scale should be outside of the operational display area. It should

be numbered at least every 30° division and have division marks of at least 5°. The 5°

and 10° division marks should be clearly distinguishable from each other. 1° division

marks may be presented where they are clearly distinguishable from each other.

5.14 Heading Line (HL)

5.14.1 A graphic line from the consistent common reference point to the bearing

scale should indicate the heading of the ship.

5.14.2 Electronic means should be provided to align the heading line to within 0.1°. If

there is more than one radar antenna (see 5.35) the heading skew (bearing offset)

should be retained and automatically applied when each radar antenna is selected.

5.14.3 Provision should be made to temporarily suppress the heading line. This

function may be combined with the suppression of other graphics.



5.15 Electronic Bearing Lines (EBLs)

5.15.1 At least two electronic bearing lines (EBLs) should be provided to measure

the bearing of any point object within the operational display area, with a maximum

system error of 1° at the periphery of the display.

5.15.2 The EBLs should be capable of measurement relative to the ships heading

and relative to true north. There should be a clear indication of the bearing reference

(i.e. true or relative).

5.15.3 It should be possible to move the EBL origin from the consistent common

reference point to any point within the operational display area and to reset the EBL to

the consistent common reference point by a fast and simple action.

5.15.4 It should be possible to fix the EBL origin or to move the EBL origin at the

velocity of own ship.

5.15.5 Means should be provided to ensure that the user is able to position the EBL

smoothly in either direction, with an incremental adjustment adequate to maintain the

system measurement accuracy requirements.

5.15.6 Each active EBL should have a numerical readout with a resolution adequate

to maintain the system measurement accuracy requirements.

5.16 Parallel Index lines (PI)

5.16.1 A minimum of four independent parallel index lines, with a means to truncate

and switch off individual lines, should be provided.

5.16.2 Simple and quick means of setting the bearing and beam range of a parallel

index line should be provided. The bearing and beam range of any selected index line

should be available on demand.

5.17 Offset Measurement of Range and Bearing

There should be a means to measure the range and bearing of one position on the

display relative to any other position within the operational display area.

5.18 User Cursor

5.18.1 A user cursor should be provided to enable a fast and concise means to

designate any position on the operational display area.

5.18.2 The cursor position should have a continuous readout to provide the range

and bearing, measured from the consistent common reference point, and/or the

latitude and longitude of the cursor position presented either alternatively or

simultaneously.

5.18.3 The cursor should provide the means to select and de-select targets,

graphics or objects within the operational display area. In addition, the cursor may be

used to select modes, functions, vary parameters and control menus outside of the

operational display area.

5.18.4 Means should be provided to easily locate the cursor position on the display.



5.18.5 The accuracy of the range and bearing measurements provided by the cursor

should meet the relevant requirements for VRM and EBL.

5.19 Azimuth Stabilization

5.19.1 The heading information should be provided by a gyrocompass or by an

equivalent sensor with a performance not inferior to the relevant standards adopted

by the Organization.

5.19.2 Excluding the limitations of the stabilizing sensor and type of transmission

system, the accuracy of azimuth alignment of the radar presentation should be within

0.5° with a rate of turn likely to be experienced with the class of ship.

5.19.3 The heading information should be displayed with a numerical resolution to

permit accurate alignment with the ship gyro system.

5.19.4 The heading information should be referenced to the consistent common

reference point (CCRP).

5.20 Display Mode of the Radar Picture

5.20.1 A True Motion display mode should be provided. The automatic reset of own

ship may be initiated by its position on the display, or time related, or both. Where the

reset is selected to occur at least on every scan or equivalent, this should be

equivalent to True Motion with a fixed origin (in practice equivalent to the previous

relative motion mode).

5.20.2 North Up and Course Up orientation modes should be provided. Head Up

may be provided when the display mode is equivalent to True Motion with a fixed

origin (in practice equivalent to the previous relative motion Head Up mode).

5.20.3 An indication of the motion and orientation mode should be provided.

5.21 Off-Centring

5.21.1 Manual off-centring should be provided to locate the selected antenna

position at any point within at least 50% of the radius from the centre of the

operational display area.

5.21.2 On selection of off-centred display, the selected antenna position should be

capable of being located to any point on the display up to at least 50%, and not more

than 75%, of the radius from the centre of the operational display area. A facility for

automatically positioning own ship for the maximum view ahead may be provided.

5.21.3 In True Motion, the selected antenna position should automatically reset up to

a 50% radius to a location giving the maximum view along own ship's course.

Provision for an early reset of selected antenna position should be provided.

5.22 Ground and Sea Stabilization Modes

5.22.1 Ground and Sea stabilization modes should be provided.

5.22.2 The stabilization mode and stabilization source should be clearly indicated.



5.22.3 The source of own ships' speed should be indicated and provided by a

sensor approved in accordance with the requirements of the Organization for the

relevant stabilization mode.

5.23 Target Trails and Past Positions

5.23.1 Variable length (time) target trails should be provided, with an indication of

trail time and mode. It should be possible to select true or relative trails from a reset

condition for all true motion display modes.

5.23.2 The trails should be distinguishable from targets.

5.23.3 Either scaled trails or past positions or both, should be maintained and

should be available for presentation within 2 scans or equivalent, following:

the reduction or increase of one range scale;

the offset and reset of the radar picture position; and

a change between true and relative trails.

5.24 Presentation of Target Information

5.24.1 Targets should be presented in accordance with the performance standards

for the Presentation of Navigation-related Information on Shipborne Navigational

Displays adopted by the Organization and with their relevant symbols according to

SN/Circ.243.

5.24.2 The target information may be provided by the radar target tracking function

and by the reported target information from the Automatic Identification System (AIS).

5.24.3 The operation of the radar tracking function and the processing of reported

AIS information is defined in these standards.

5.24.4 The number of targets presented, related to display size, is defined in Table 1.

An indication should be given when the target capacity of radar tracking or AIS

reported target processing/display capability is about to be exceeded.

5.24.5 As far as practical, the user interface and data format for operating,

displaying and indicating AIS and radar tracking information should be consistent.

5.25 Target Tracking (TT) and Acquisition

5.25.1 General

Radar targets are provided by the radar sensor (transceiver). The signals may be

filtered (reduced) with the aid of the associated clutter controls. Radar targets may be

manually or automatically acquired and tracked using an automatic Target Tracking

(TT) facility.

5.25.1.1 The automatic target tracking calculations should be based on the

measurement of radar target relative position and own ship motion.

5.25.1.2 Any other sources of information, when available, may be used to support the

optimum tracking performance.



5.25.1.3 TT facilities should be available on at least the 3, 6, and 12 nm range scales.

Tracking range should extend to a minimum of 12 nm.

5.25.1.4 The radar system should be capable of tracking targets having the maximum

relative speed relevant to its classification for normal or high own ship speeds (see

5.3).

5.25.2 Tracked Target Capacity

5.25.2.1 In addition to the requirements for processing of targets reported by AIS, it

should be possible to track and provide full presentation functionality for a minimum

number of tracked radar targets according to Table 1.

5.25.2.2 There should be an indication when the target tracking capacity is about to

be exceeded. Target overflow should not degrade the radar system performance.

5.25.3 Acquisition

5.25.3.1 Manual acquisition of radar targets should be provided with provision for

acquiring at least the number of targets specified in Table 1.

5.25.3.2 Automatic acquisition should be provided where specified in Table 1. In this

case, there should be means for the user to define the boundaries of the

auto-acquisition area.

5.25.4 Tracking

5.25.4.1 When a target is acquired, the system should present the trend of the target's

motion within one minute and the prediction of the targets' motion within 3 minutes.

5.25.4.2 TT should be capable of tracking and updating the information of all acquired

targets automatically.

5.25.4.3 The system should continue to track radar targets that are clearly

distinguishable on the display for 5 out of 10 consecutive scans or equivalent.

5.25.4.4 The TT design should be such that target vector and data smoothing is

effective, while target maneuvers should be detected as early as possible.

5.25.4.5 The possibility of tracking errors, including target swap, should be minimized

by design.

5.25.4.6 Separate facilities for cancelling the tracking of any one and of all target(s)

should be provided.

5.25.4.7 Automatic tracking accuracy should be achieved when the tracked target has

achieved a steady state, assuming the sensor errors allowed by the relevant

performance standards of the Organization.

5.25.4.7.1 For ships capable of up to 30 kn true speed, the tracking facility should

present, within 1 min steady state tracking, the relative motion trend and after 3

minutes, the predicted motion of a target, within the following accuracy values (95%

probability):



TABLE 3

Tracked Target Accuracy (95% probability figures)

Time of

steady state

(minutes)

Relative

Course

(degrees)

Relative

Speed

(kn)

CPA

(nm)

TCPA

(minutes)

True

Course

(degrees)

True

Speed

(kn)

1 min: Trend 11

1.5 or 10%

(whichever is

greater)

1.0 - - -

3 min: Motion 3

0.8 or

1%(whichever is

greater)

0.3 0.5 5

0.5 or

1%(whichever is

greater)

Accuracy may be significantly reduced during or shortly after acquisition, own ship

manoeuvre, a manoeuvre of the target, or any tracking disturbance and is also

dependent on own ship's motion and sensor accuracy.

Measured target range and bearing should be within 50 m (or +/-1% of target range)

and 2°.

The testing standard should have detailed target simulation tests as a means to

confirm the accuracy of targets with relative speeds of up to 100 kn. Individual

accuracy values shown in the table above may be adapted to account for the relative

aspects of target motion with respect to that of own ship in the testing scenarios used.

5.25.4.7.2 For ships capable of speeds in excess of 30 kn (typically High-Speed Craft

(HSC)) and with speeds of up to 70 kn, there should be additional steady state

measurements made to ensure that the motion accuracy, after 3 minutes of steady

state tracking, is maintained with target relative speeds of up to 140 kn.

5.25.4.8 A ground referencing function, based on a stationary tracked target, should

be provided. Targets used for this function should be marked with the relevant symbol

defined in SN/Circ.243.

5.26 Automatic Identification System (AIS) Reported Targets

5.26.1 General

Reported targets provided by the AIS may be filtered according to user-defined

parameters. Targets may be sleeping, or may be activated. Activated targets are

treated in a similar way to radar tracked targets.

5.26.2 AIS Target Capacity

In addition to the requirements for radar tracking, it should be possible to display and

provide full presentation functionality for a minimum number of sleeping and activated

AIS targets according to Table 1. There should be an indication when the capacity of

processing/display of AIS targets is about to be exceeded.



5.26.3 Filtering of AIS Sleeping Targets

To reduce display clutter, a means to filter the presentation of sleeping AIS targets

should be provided, together with an indication of the filter status. (e.g. by target range,

CPA/TCPA or AIS target class A/B, etc.). It should not be possible to remove

individual AIS targets from the display.

5.26.4 Activation of AIS Targets

A means to activate a sleeping AIS target and to deactivate an activated AIS target

should be provided. If zones for the automatic activation of AIS targets are provided,

they should be the same as for automatic radar target acquisition. In addition,

sleeping AIS targets may be automatically activated when meeting user defined

parameters (e.g. target range, CPA/TCPA or AIS target class A/B).

5.26.5 AIS Presentation Status

TABLE 4

The AIS presentation status should be indicated as follows:

Function Cases to be Presented Presentation

AIS ON/OFF

AIS processing switched

ON/graphical presentation

switched OFF

AIS processing switched

ON/graphical presentation

switched ON

Alphanumeric or

graphical

Filtering of sleeping

AIS targets

Filter status Filter status Alphanumeric or

graphical Activation of

Targets

Activation criteria Graphical

CPA/TCPA Alarm Function ON/OFF

Sleeping targets included

Function ON/OFF

Sleeping targets included

Alphanumeric and

graphical Lost Target

Alarm

Function ON/OFF

Lost target filter criteria

Function ON/OFF

Lost target filter criteria

Alphanumeric and

graphical

Target

Association

Function ON/OFF

Association criteria

Default target priority

Function ON/OFF

Association criteria

Default target priority

Alphanumeric

5.27 AIS Graphical Presentation

Targets should be presented with their relevant symbols according to the performance

standards for the Presentation of Navigation-related Information on Shipborne

Navigational Displays adopted by the Organization and SN/Circ.243.

5.27.1 AIS targets that are displayed should be presented as sleeping targets by

default.

5.27.2 The course and speed of a tracked radar target or reported AIS target should

be indicated by a predicted motion vector. The vector time should be adjustable and

valid for presentation of any target regardless of its source.

5.27.3 A permanent indication of vector mode, time and stabilization should be

provided.



5.27.4 The consistent common reference point should be used for the alignment of

tracked radar and AIS symbols with other information on the same display.

5.27.5 On large scale/low range displays, a means to present the true scale outline

of an activated AIS target should be provided. It should be possible to display the past

track of activated targets.

5.28 AIS and Radar Target Data

5.28.1 It should be possible to select any tracked radar or AIS target for the

alphanumeric display of its data. A target selected for the display of its alphanumeric

information should be identified by the relevant symbol. If more than one target is

selected for data display, the relevant symbols and the corresponding data should be

clearly identified. There should be a clear indication to show that the target data is

derived from radar or from AIS.

5.28.2 For each selected tracked radar target, the following data should be

presented in alphanumeric form: source(s) of data, actual range of target, actual

bearing of target, predicted target range at the closest point of approach (CPA),

predicted time to CPA (TCPA), true course of target, true speed of target.

5.28.3 For each selected AIS target the following data should be presented in

alphanumeric form: Source of data, ship's identification, navigational status, position

where available and its quality, range, bearing, COG, SOG, CPA and TCPA. Target

heading and reported rate of turn should also be made available. Additional target

information should be provided on request.

5.28.4 If the received AIS information is incomplete, the absent information should

be clearly indicated as "missing" within the target data field.

5.28.5 The data should be displayed and continually updated, until another target is

selected for data display or until the window is closed.

5.28.6 Means should be provided to present own ship AIS data on request.

5.29 Operational Alarms

A clear indication of the cause for all alarm criteria should be given.

5.29.1 If the calculated CPA and TCPA values of a tracked target or activated AIS

target are less than the set limits:

A CPA/TCPA alarm should be given.

The target should be clearly indicated.

5.29.2 The preset CPA/TCPA limits applied to targets from radar and AIS should be

identical. As a default state, the CPA/TCPA alarm functionality should be applied to all

activated AIS targets. On user request the CPA/TCPA alarm functionality may also be

applied to sleeping targets.

5.29.3 If a user defined acquisition/activation zone facility is provided, a target not

previously acquired/activated entering the zone, or is detected within the zone, should



be clearly identified with the relevant symbol and an alarm should be given. It should

be possible for the user to set ranges and outlines for the zone.

5.29.4 The system should alert the user if a tracked radar target is lost, rather than

excluded by a pre-determined range or pre-set parameter. The target's last position

should be clearly indicated on the display.

5.29.5 It should be possible to enable or disable the lost target alarm function for

AIS targets. A clear indication should be given if the lost target alarm is disabled.


The AIS lost target alarm function is enabled.

The target is of interest, according to lost target filter criteria.

A message is not received for a set time, depending on the nominal reporting

rate of the AIS target.

Then:

The last known position should be clearly indicated as a lost target and an

alarm be given.

The indication of the lost target should disappear if the signal is received

again, or after the alarm has been acknowledged.

A means of recovering limited historical data from previous reports should be

provided.

5.30 AIS and Radar Target Association

An automatic target association function based on harmonized criteria avoids the

presentation of two target symbols for the same physical target.

5.30.1 If the target data from AIS and radar tracking are both available and if the

association criteria (e.g. position, motion) are fulfilled such that the AIS and radar

information are considered as one physical target, then as a default condition, the

activated AIS target symbol and the alphanumeric AIS target data should be

automatically selected and displayed.

5.30.2 The user should have the option to change the default condition to the

display of tracked radar targets and should be permitted to select either radar tracking

or AIS alphanumeric data.

5.30.3 For an associated target, if the AIS and radar information become sufficiently

different, the AIS and radar information should be considered as two distinct targets

and one activated AIS target and one tracked radar target should be displayed. No

alarm should be raised.

5.31 Trial Manoeuvre

The system should, where required by table 1, be capable of simulating the predicted

effects of own ships manoeuvre in a potential threat situation and should include own



ship's dynamic characteristics. A trial manoeuvre simulation should be clearly

identified. The requirements are:

The simulation of own ship course and speed should be variable.

A simulated time to manoeuvre with a countdown should be provided.

During simulation, target tracking should continue and the actual target data

should be indicated.

Trial manoeuvre should be applied to all tracked targets and at least all

activated AIS targets.

5.32 The Display of Maps, Navigation Lines and Routes

5.32.1 It should be possible for the user to manually create and change, save, load

and display simple maps/navigation lines/routes referenced to own ship or a

geographical position. It should be possible to remove the display of this data by a

simple operator action.

5.32.2 The maps/navigation lines/routes may consist of lines, symbols and

reference points.

5.32.3 The appearance of lines, colours and symbols are as defined in SN/Circ.243.

5.32.4 The maps/navigation lines/route graphics should not significantly degrade

the radar information.

5.32.5 The maps/navigation lines/routes should be retained when the equipment is

switched OFF.

5.32.6 The maps/navigation lines/route data should be transferable whenever a

relevant equipment module is replaced.

5.33 The Display of Charts

5.33.1 The radar system may provide the means to display ENC and other vector

chart information within the operational display area to provide continuous and

real-time position monitoring. It should be possible to remove the display of chart data

by a single operator action.

5.33.2 The ENC information should be the primary source of information and should

comply with IHO relevant standards. Status of other information should be identified

with a permanent indication. Source and update information should be made

available.

5.33.3 As a minimum, the elements of the ECDIS Standard Display should be made

available for individual selection by category or layer, but not as individual objects.

5.33.4 The chart information should use the same reference and co-ordinate criteria

as the radar/AIS, including datum, scale, orientation, CCRP and stabilization mode.

5.33.5 The display of radar information should have priority. Chart information

should be displayed such that radar information is not substantially masked, obscured

or degraded. Chart information should be clearly perceptible as such.



5.33.6 A malfunction of the source of chart data should not affect the operation of

the radar/AIS system.

5.33.7 Symbols and colours should comply with the performance standards for the

Presentation of Navigation-related Information on Shipborne Navigational Displays

adopted by the Organization (SN/Circ.243).

5.34 Alarms and Indications

Alarms and indications should comply with the performance standards for the

Presentation of Navigation-related Information on Shipborne Navigational Displays

adopted by the Organization.

5.34.1 A means should be provided to alert the user of "picture freeze".

5.34.2 Failure of any signal or sensor in use, including; gyro, log, azimuth, video,

sync and heading marker, should be alarmed. System functionality should be limited

to a fall back mode or in some cases, the display presentation should be inhibited (see

fallback modes, section 9).

5.35 Integrating Multiple Radars

5.35.1 The system should safeguard against single point system failure. Fail- safe

condition should be applied in the event of an integration failure.

5.35.2 The source and any processing or combination of radar signals should be

indicated.

5.35.3 The system status for each display position should be available.

6 ERGONOMIC CRITERIA

6.1 Operational Controls

6.1.1 The design should ensure that the radar system is simple to operate.

Operational controls should have a harmonized user interface and be easy to identify

and simple to use.

6.1.2 The radar system should be capable of being switched ON or OFF at the

main system radar display or at a control position.

6.1.3 The control functions may be dedicated hardware, screen accessed or a

combination of these; however the primary control functions should be dedicated

hardware controls or soft keys, with an associated status indication in a consistent

and intuitive position.

6.1.4 The following are defined as primary radar control functions and should be

easily and immediately accessible:

Radar Standby/RUN, Range scale selection, Gain, tuning function (if applicable),

Anti-clutter rain, Anti-clutter sea, AIS reporting function on/off, Alarm acknowledge,

Cursor, a means to set EBL/VRM, display brightness and acquisition of radar targets.

6.1.5 The primary functions may also be operated from a remote operating position

in addition to the main controls.



6.2 Display Presentation

6.2.1 The display presentation should comply with the performance standards for

the Presentation of Navigation-related Information on Shipborne Navigational

Displays adopted by the Organization.

6.2.2 The colours, symbols and graphics presented should comply with

SN/Circ.243.

6.2.3 The display sizes should conform to those defined in Table 1.

6.3 Instructions and Documentation

6.3.1 Documentation Language

The operating instructions and manufacturer's documentation should be written in a

clear and comprehensible manner and should be available at least in the English

language.

6.3.2 Operating Instructions

The operating instructions should contain a qualified explanation and/or description of

information required by the user to operate the radar system correctly, including:

appropriate settings for different weather conditions;

monitoring the radar system's performance;

operating in a failure or fall-back situation;

limitations of the display and tracking process and accuracy, including any

delays;

using heading and SOG/COG information for collision avoidance;

limitations and conditions of target association;

criteria of selection for automatic activation and cancellation of targets;

methods applied to display AIS targets and any limitations;

principles underlying the trial manoeuvre technology, including simulation of

own ship's manoeuvring characteristics, if provided;

alarms and indications;

installation requirements as listed under section 7.5;

radar range and bearing accuracies; and

any special operation (e.g. tuning) for the detection of SARTs; and

the role of the CCRP for radar measurements and its specific value.

6.3.3 Manufacturer's Documentation

6.3.3.1 The manufacturer's documentation should contain a description of the radar

system and factors that may affect detection performance, including any latency in

signal processing.



6.3.3.2 Documentation should describe the basis of AIS filter criteria and AIS/radar

target association criteria.

6.3.3.3 The equipment documentation should include full details of installation

information, including additional recommendations on unit location and factors that

may degrade performance or reliability.

7 DESIGN AND INSTALLATION

7.1 Design for Servicing

7.1.1 As far as is practical, the radar system should be of a design to facilitate

simple fault diagnosis and maximum availability.

7.1.2 The radar system should include a means to record the total operational

hours for any components with a limited life.

7.1.3 The documentation should describe any routine servicing requirements and

should include details of any restricted life components.

7.2 Display

The display device physical requirements should meet those specified in the

performance standards for the Presentation of Navigation-related Information on

Shipborne Navigational Displays adopted by the Organization (SN/Circ.243) and

those specified in Table 1.

7.3 Transmitter Mute

The equipment should provide a mute facility to inhibit the transmission of radar

energy over a preset sector. The mute sector should be set up on installation. An

indication of sector mute status should be available.

7.4 Antenna

7.4.1 The antenna should be designed to start operating and to continue to operate

in relative wind speeds likely to be encountered on the class of ship on which it is

installed.

7.4.2 The combined radar system should be capable of providing an appropriate

information update rate for the class of ship on which it is installed.

7.4.3 The antenna side lobes should be consistent with satisfying the system

performance as defined in this standard.

7.4.4 There should be a means to prevent antenna rotation and radiation during

servicing, or while personnel are in the vicinity of up-mast units.

7.5 Radar System Installation

Requirements and guidelines for the radar system installation should be included in

the manufacturers' documentation. The following subjects should be covered:

7.5.1 The Antenna

Blind sectors should be kept to a minimum, and should not be placed in an arc of the

horizon from the right ahead direction to 22.5° abaft the beam and especially should



avoid the right ahead direction (relative bearing 000°). The installation of the antenna

should be in such a manner that the performance of the radar system is not

substantially degraded. The antenna should be mounted clear of any structure that

may cause signal reflections, including other antenna and deck structure or cargo. In

addition, the height of the antenna should take account of target detection

performance relating to range of first detection and target visibility in sea clutter.

7.5.2 The Display

The orientation of the display unit should be such that the user is looking ahead, the

lookout view is not obscured and there is minimum ambient light on the display.

7.6 Operation and Training

7.6.1 The design should ensure that the radar system is simple to operate by

trained users.

7.6.2 A target simulation facility should be provided for training purposes.

8 INTERFACING

8.1 Input Data

The radar system should be capable of receiving the required input information from:

a gyro-compass or transmitting heading device (THD);

a speed and distance measuring equipment (SDME);

an electronic position-fixing system (EPFS);

an Automatic Identification System (AIS); or

other sensors or networks providing equivalent information acceptable to the

Organization.

The radar should be interfaced to relevant sensors required by these performance

standards in accordance with recognized international standards.

8.2 Input Data Integrity and Latency

8.2.1 The radar system should not use data indicated as invalid. If input data is

known to be of poor quality this should be clearly indicated.

8.2.2 As far as is practical, the integrity of data should be checked, prior to its use,

by comparison with other connected sensors or by testing to valid and plausible data

limits.

8.2.3 The latency of processing input data should be minimized.

8.3 Output Data

8.3.1 Information provided by any radar output interface to other systems should

be in accordance with international standards.

8.3.2 The radar system should provide an output of the display data for the voyage

data recorder (VDR).



8.3.3 At least one normally closed contact (isolated) should be provided for

indicating failure of the radar.

8.3.4 The radar should have a bi-directional interface to facilitate communication

so that alarms from the radar can be transferred to external systems and so that

audible alarms from the radar can be muted from external systems, the interface

should comply with relevant international standards.

9 BACKUP AND FALLBACK ARRANGEMENTS

In the event of partial failures and to maintain minimum basic operation, the fallback

arrangements listed below should be provided. There should be a permanent

indication of the failed input information.

9.1 Failure of Heading Information (Azimuth Stabilization)

9.1.1 The equipment should operate satisfactorily in an unstabilized head-up

mode.

9.1.2 The equipment should switch automatically to the unstabilized head up mode

within 1 minute after the azimuth stabilization has become ineffective.

9.1.3 If automatic anti-clutter processing could prevent the detection of targets in

the absence of appropriate stabilization, the processing should switch off

automatically within 1 minute after the azimuth stabilization has become ineffective.

9.1.4 An indication should be given that only relative bearing measurements can

be used.

9.2 Failure of Speed through the Water Information

A means of manual speed input should be provided and its use clearly indicated.

9.3 Failure of Course and Speed Over Ground Information

The equipment may be operated with course and speed through the water

information.

9.4 Failure of Position Input Information

The overlay of chart data and geographically referenced maps should be disabled if

only a single Reference Target is defined and used, or the position is manually

entered.

9.5 Failure of Radar Video Input Information

In the absence of radar signals, the equipment should display target information

based on AIS data. A frozen radar picture should not be displayed.

9.6 Failure of AIS Input Information

In the absence of AIS signals, the equipment should display the radar video and

target database.

9.7 Failure of an Integrated or Networked System

The equipment should be capable of operating equivalent to a stand alone system.



Appendix 1 – References

IMO SOLAS chapters IV, V and X Carriage rules.

IMO resolution A. 278(VII) Supplement to the recommendation on PS for

navigational radar equipment.

IMO resolution A. 424(XI) Performance standards for gyro-compasses.

IMO resolution A. 477(XII) Performance standards for radar equipment.

IMO resolution A. 694(17) General Requirements for shipborne radio

equipment forming part of the global maritime

distress and safety system and for electronically

navigational aids.

IMO resolution A. 817(19)

as amended Performance standards for ECDIS.

IMO resolution A. 821(19) Performance standards for gyrocompasses for

high-speed craft.

IMO resolution A. 824(19) Performance standards for devices to indicate speed

and distance.

IMO resolution MSC. 86(70) Performance standards for INS.

IMO resolution MSC. 64(67) Recommendations on new and amended

performance standards (Annex 2 revised by

MSC.114 (73)).

IMO resolution MSC. 112(73) Revised performance standards for ship borne

global positioning (GPS) receiver equipment.

IMO resolution MSC. 114(73) Revised performance standards for shipborne DGPS

and DGLONASS maritime radio beacon receiver

equipment.

IMO resolution MSC. 116(73) Performance standards for marine transmitting

heading devices (THD).

IMO MSC Circ.982 Guidelines on ergonomic criteria for bridge

equipment and layout.

IHO S-52 appendix 2 Color and symbol specification for ECDIS.

IEC62388 Radar Test Standard (replacing 60872 and 60936

series of test standards).

IEC60945 Maritime navigation and radio communication

equipment and systems – General requirements –

Methods of testing and required test results.


equipment and systems – Digital interfaces.




equipment and systems – Electronic chart display

and information system (ECDIS) – Operational and

performance requirements, methods of testing and

required test results.

IEC62288 Presentation and display of navigation information.

ISO 9000 (all parts) Quality management/assurance standards.

Appendix 2 – Definitions

Activated AIS target A target representing the automatic or manual

activation of a sleeping target for the display of

additional graphically presented information. The

target is displayed by an "activated target" symbol

including:

-a vector (COG/SOG);

-the heading; and

-ROT or direction of turn indication (if available) to

indicate initiated course changes.

Acquisition of a radar target Process of acquiring a target and initiating its

tracking.

Activation of an AIS target Activation of a sleeping AIS target for the display of

additional graphical and alphanumerical information.

Acquired radar target Automatic or manual acquisition initiates radar

tracking. Vectors and past positions are displayed

when data has achieved a steady state condition.

AIS Automatic Identification System.

AIS target A target generated from an AIS message. See

activated target, lost target, selected target and

sleeping target.

Associated target If an acquired radar target and an AIS reported target

have similar parameters (e.g. position, course, speed)

complying with an association algorithm, they are

considered to be the same target and become an

associated target.

Acquisition/activation zone A zone set up by the operator in which the system

should automatically acquire radar targets and

activate reported AIS targets when entering the

zone.



CCRP Consistent Common Reference Point: A location on

own ship, to which all horizontal measurements such

as target range, bearing, relative course, relative

speed, closest point of approach (CPA) or time to

closest point of approach (TCPA) are referenced,

typically the conning position of the bridge.

CPA/TCPA Closest Point of Approach/Time to the Closest Point

of Approach: Distance to the closest point of

approach (CPA) and time to the closest point of

approach (TCPA). Limits are set by the operator

related to own ship.

Course Over Ground (COG) Direction of the ship's movement relative to the

earth, measured on board the ship, expressed in

angular units from true north.

Course Through Water (CTW) Direction of the ship's movement through the water,

defined by the angle between the meridian through

its position and the direction of the ship's

movement through the water, expressed in angular

units from true north.

Dangerous target A target whose predicted CPA and TCPA are

violating the values as preset by the operator. The

respective target is marked by a "dangerous target"

symbol.

Display modes Relative motion: means a display on which the

position of own ship remains fixed, and all targets

move relative to own ship.

True motion: a display across which own ship

moves with its own true motion.

Display orientation North up display: an azimuth stabilised

presentation which uses the gyro input (or

equivalent) and north is uppermost on the

presentation.

Course up display: an azimuth stabilised

presentation which uses the gyro input or

equivalent and the ship's course is uppermost on

the presentation at the time of selection.

Head up display: an unstabilised presentation in

which own ship's heading is uppermost on the

presentation.

ECDIS Electronic Chart Display and Information System.



ECDIS Display Base The level of information which cannot be removed

from the ECDIS display, consisting of information

which is required at all times in all geographic areas

and all circumstances. It is not intended to be

sufficient for safe navigation.

ECDIS Standard Display The level of information that should be shown when

a chart is first displayed on ECDIS. The level of the

information it provides for route planning or route

monitoring may be modified by the mariner

according to the mariner's needs.

ENC Electronic Navigational Chart. The database

standardised as to content, structure and format

according to relevant IHO standards and issued by,

or on the authority of, a government.

EPFS Electronic Position-fixing System.

ERBL Electronic bearing line carrying a marker, which is

combined with the range marker, used to measure

range and bearing from own ship or between two

objects.

Evaporation duct A low lying duct (a change in air density) that traps

the radar energy so that it propagates close to the

sea surface. Ducting may enhance or reduce radar

target detection ranges.

Heading Direction in which the bow of a ship is pointing

expressed as an angular displacement from north.

HSC High-speed craft (HSC) are vessels which comply

with the definition in SOLAS for high speed craft.

Latency The delay between actual and presented data.

Lost AIS target A target representing the last valid position of an AIS

target before the reception of its data was lost. The

target is displayed by a "lost AIS target" symbol.

Lost tracked target Target information is no longer available due to

poor, lost or obscured signals. The target is

displayed by a "lost tracked radar target"

symbol.

Maps/Nav lines Operator defined or created lines to indicate

channels, Traffic Separation Schemes or borders of

any area important for navigation.



Operational display area Area of the display used to graphically present chart

and radar information, excluding the user dialogue

area. On the chart display this is the area of the chart

presentation. On the radar display this is the area

encompassing the radar image.

Past positions Equally time-spaced past position marks of a

tracked or reported target and own ship. The past

positions' track may be either relative or true.

Radar (Radio direction and ranging) A radio system that

allows the determination of distance and direction

of reflecting objects and of transmitting devices.

Radar beacon A navigation aid which responds to the radar

transmission by generating a radar signal to identify

its position and identity.

Radar detection false alarm The probability of a radar false alarm represents the

probability that noise will cross the detection

threshold and be called a target when only noise is

present.

Radar target Any object fixed or moving whose position and

motion is determined by successive radar

measurements of range and bearing.

Radar target enhancer An electronic radar reflector, the output of which is

an amplified version of the received radar pulse

without any form of processing except limiting.

Reference target Symbol indicating that the associated tracked

stationary target (e.g. a navigational mark) is used as

a speed reference for the ground stabilization.

Relative bearing Direction of a target's position from own ship's

reference location expressed as an angular

displacement from own ship's heading.

Relative course Direction of motion of a target relative to own ship's

direction. (Bearing.)

Relative motion Combination of relative course and relative speed.

Relative speed Speed of a target relative to own ship's speed data.

Rate of turn Change of heading per time unit

SART Search and Rescue Transponder.

SDME Speed and Distance Measurement Equipment.



Selected target A manually selected target for the display of detailed

alphanumeric information in a separate data display

area. The target is displayed by a "selected target"

symbol.

Sleeping AIS target A target indicating the presence and orientation of

a vessel equipped with AIS in a certain location.

The target is displayed by a "sleeping target"

symbol. No additional information is presented until

activated.

Stabilization modes Ground stabilization: Display mode in which

speed and course information are referred to the

ground, using ground track input data, or EPFS as

reference.

Sea stabilization: Display mode in which speed

and course information are referred to the sea,

using gyro or equivalent and water speed log input

as reference.

Standard display The level of information that should be shown when

a chart is first displayed on ECDIS. The level of the

information it provides for route planning or route

monitoring may be modified by the mariner

according to the mariner's needs.

Standard radar reflector Reference reflector mounted 3.5 m above sea

level with 10 m2 effective reflecting area at X-band.

Steady state tracking Tracking a target, proceeding at steady motion

-after completion of the acquisition process, or

-without a manoeuvre of target or own ship, or

-without target swap or any disturbance

Speed Over Ground (SOG) Speed of the ship relative to the earth, measured on

board of the ship.

Speed Through Water Speed of the ship relative to the water surface.

SOLAS International Convention for the Safety of Life at Sea.

Suppressed area An area set up by the operator within which targets

are not acquired.

Target swap Situation in which the incoming radar data for a

tracked target becomes incorrectly associated with

another tracked target or a non-tracked radar echo.



Target's predicted motion Prediction of a target's future course and speed

based on line extrapolation from its present motion

as determined by past measurements of its range

and bearing on the radar.

Target Tracking Computer process of observing the sequential

changes in the position of a radar target in order to

establish its motion. Such a target is a Tracked

Target.

Trails Tracks displayed by the radar echoes of targets in

the form of an afterglow. Trails may be true or

relative.

Trial manoeruvre Graphical simulation facility used to assist the

operator to perform a proposed manoeuvre for

navigation and collision avoidance purposes, by

displaying the predicted future status of at least all

acquired or activated targets as a result of own ship's

simulated manoeuvres.

True bearing Direction of a target from own ship's reference

location or from another target's position

expressed as an angular displacement from true

north.

True course Direction of motion relative to ground or to sea, of a

target expressed as an angular displacement from

north.

True motion Combination of true course and true speed.

True speed Speed of a target relative to ground, or to sea.

Vector modes True vector: Vector representing the predicted true

motion of a target, showing course and speed with

reference to the ground.

Relative vector: Predicted movement of a target

relative to own ship's motion.

User Configured Presentation A display presentation configured by the user for a

specific task at hand. The presentation may

include radar and/or chart information, in

combination with other navigation or ship related

data.

User Dialogue Area Is an area of the display consisting of data fields

and/or menus that is allocated to the interactive

presentation and entry or selection of operational

parameters, data and commands mainly in

alphanumeric form.



Annex 2

GUIDELINES FOR THE PRESENTATION OF NAVIGATION-RELATED

SYMBOLS

(SN.1/Circ.243/Rev.1, annex 1)

NAVIGATION-RELATED SYMBOLS

Table 1: Own Ship Symbols

Topic Symbol Description

Own ship

Double circle, located at own ship's reference

position.

Use of this symbol is optional, if own ship position is

shown by the combination of Heading Line and

Beam Line.

Own Ship True

scale outline

True scale outline located relative to own ship's

reference position, oriented along own ship's

heading.

Used on small ranges/large scales.

Own Ship Radar

Antenna Position

Cross, located on a true scale outline of the ship at

the Physical location of the radar antenna that is the

current source of displayed radar video.

Own Ship

Heading line

Solid line thinner than the speed vector line style,

drawn to the bearing ring or of fixed length, if the

bearing ring is not displayed. Origin is at own ship's

reference point.

Own Ship Beam

line

Solid line of fixed length; optionally length variable

by operator. Midpoint at own ship's reference point.

Own Ship Speed

vector

Dashed line – short dashes with spaces

approximately twice the line width of heading line.

Time increments between the origin and endpoint

may optionally be marked along the vector using

short intersecting lines.

To indicate Water/Ground stabilization optionally

one arrowhead for water stabilization and two

arrowheads for ground stabilization may be added.



Own Ship Path

prediction

A curved vector may be provided as a path predictor.

Own Ship

Past Track

Thick line for primary source. Thin line for secondary

source.

Optional time marks are allowed.

Table 2: Tracked Radar Target Symbols


Tracked Target

including

Dangerous

Target

Solid filled or unfilled circle located at target position.

The course and speed vector should be displayed as

dashed line, with short dashes with spaces

approximately twice the line width.

Optionally, time increments, may be marked along

the vector.

For a "Dangerous Target", bold, red (on colour

display) solid circle with course and speed vector,

flashing until acknowledged.

Target in

Acquisition State

Circle segments in the acquired target state.

For automatic acquisition, bold circle segments,

flashing and red (on colour display) until

acknowledged.

Lost Target

Bold lines across the circle, flashing until

acknowledged.

Selected Target

A square indicated by its corners centred around the

target symbol.

Target Past

Positions

Dots, equally spaced by time.



Tracked

Reference Target R Large R adjacent to designated tracked target.

Multiple reference targets should be marked as R1,

R2, R3, etc.

Table 3: AIS Target Symbols


AIS Target

(sleeping)

An isosceles, acute-angled triangle should be used.

The triangle should be oriented by heading, or COG

if heading missing. The reported position should be

located at centre and half the height of the triangle.

The symbol of the sleeping target should be smaller

than that of the activated target.

Activated AIS

Target

Including

Dangerous

Target

An isosceles, acute-angled triangle should be used.

The triangle should be oriented by heading, or COG

if heading missing. The reported position should be

located at centre and half the height of the triangle.

The COG/SOG vector should be displayed as a

dashed line with short dashes with spaces

approximately twice the line width. Optionally, time

increments may be marked along the vector.

The heading should be displayed as a solid line

thinner than speed vector line style, length twice of

the length of the triangle symbol. Origin of the

heading line is the apex of the triangle.

The turn should be indicated by a flag of fixed length

added to the heading line.

A path predictor may be provided as curved vector.

For a "Dangerous AIS Target", bold, red (on

colour display) solid triangle with course and speed

vector, flashing until acknowledged.

AIS Target –

True Scale

Outline

A true scale outline may be added to the triangle

symbol. It should be:

Located relative to reported position and according

to reported position offsets, beam and length.

Oriented along target's heading.

Used on low ranges/large scales.



Selected target

A square indicated by its corners should be drawn

around the activated target symbol.

Lost target

Triangle with bold solid cross. The triangle should

be oriented per last known value. The cross should

have a fixed orientation. The symbol should flash

until acknowledged.

The target should be displayed without vector,

heading and rate of turn indication.

Target Past

Positions

Dots, equally spaced by time.

AIS Search and

Rescue

Transmitter

(AIS-SART)

A circle containing a cross drawn with solid lines.

Table 4: Other Symbols


Monitored Route Dashed bold line, waypoints (WPT) as circles.

Planned or

Alternate Route Dotted line, WPT as circles.

Trial Manoeuvre Large T on screen.

Simulation Mode S Large S on screen.

Cursor

Crosshair (two alternatives, one with open centre).

Range Rings

Solid circles.




Variable Range

Markers (VRM)

Circle.

Additional VRM should be distinguishable from the

primary VRM.

Electronic

Bearing Lines

(EBL)

Dashed line.

Additional EBL should be distinguishable from the

primary EBL.

Acquisition/

Activation Area

Solid line boundary for an area.

Event Mark

Rectangle with diagonal line, clarified by added text

(e.g. "MOB" for man overboard cases).

Table 4.1: Improved symbols for portrayal of AIS Aids to Navigation (AIS AtoN)

Type of AIS AtoN

(Type of code in AIS msg.

21)

Symbol

(Physical)

Symbol

(Virtual)

Description

Portrayal when indication of

type is not selected

Solid diamond

(Shown with chart symbol. Chart symbol

not required for radar.)

Note: Applicable only for Physical AIS

AtoN

Default, type not specified

(0)

Reference point (1)

Light, without sectors (5)

Light, with sectors (6)

Leading Light Front (7)

Leading Light Rear (8)

Physical: Solid diamond



Virtual: Dotted diamond with cross hair

centred at reported position

Fixed structure

offshore/obstruction (3)

Light Vessel/LANBY/Rigs

(31)

Solid diamond



Note: Fixed structure offshore/obstruction

and Light Vessel/LANBY/Rigs versions

are not applicable for Virtual AIS AtoN



Type of AIS AtoN


21)

Symbol

(Physical)

Symbol

(Virtual)

Description

Racon (2)

Solid diamond with double circle of black

inner circle on the top of diamond

Note: Racon version is not applicable for

Virtual AIS AtoN

Emergency Wreck Mark (4)

Physical: Solid diamond with cross on the

top of diamond




centred at reported position and cross on

the top of diamond

Beacon, Cardinal N (9)

Floating, Cardinal Mark N

(20)

Physical: Solid diamond with 2 triangles,

one above the other, point upward, on top

of diamond




centred at reported position and 2

triangles, one above the other, points

upward, on the top of diamond

Beacon, Cardinal E (10)

Floating, Cardinal Mark E

(21)


one above the other, base to base, on the

top of diamond





triangles, one above the other, base to

base, on the top of diamond

Beacon, Cardinal S (11)

Floating, Cardinal Mark S

(22)


one above the other, point downward, on

the top of diamond





triangles, one above the other, points

downward, on the top of diamond



Type of AIS AtoN


21)

Symbol

(Physical)

Symbol

(Virtual)

Description

Beacon, Cardinal W (12)

Floating, Cardinal Mark W

(23)


one above the other, point to point, on the

top of diamond





triangles, one above the other, point to

point, on the top of diamond

Beacon, Port hand (13)

Beacon, Preferred Channel

Port hand (15)

Port hand Mark (24)

Preferred Channel Port hand

(26)

Physical: Solid diamond with rectangle,

short side up, on the top of diamond




centred at reported position and

rectangle, short side up, on the top of

diamond

Beacon, Starboard hand (14)

Beacon, Preferred Channel

Starboard hand (16)

Starboard hand Mark (25)

Preferred Channel Starboard

hand (27)

Physical: Solid diamond with triangle,

points upward, on the top of diamond




centred at reported position and triangle,

points upward, on the top of diamond

Beacon, Isolated danger (17)

Isolated danger (28)

Beacon, Safe

Physical: Solid diamond with 2 circles,

one above the other, on the top of

diamond




centred at reported position and 2 circles,

one above the other, on the top of

diamond

Beacon, Safe water (18)

Safe Water (29)

Physical: Solid diamond with circle on the

top of diamond




centred at reported position and circle on

the top of diamond



Type of AIS AtoN


21)

Symbol

(Physical)

Symbol

(Virtual)

Description

Beacon, Special mark (19)

Special Mark (30)

Physical: Solid diamond with bold

outlined "X" on the top of diamond




centred at reported position and bold

outlined "X" on the top of diamond

Table 4.2 – Portrayal of AIS AtoN indicating off position or failure

Type of failure condition Symbol

(Physical)

Description

AIS AtoN indicating to be in

Off Position

Failure is indicated using yellow caution colour for the

basic diamond part of the symbol with cross hair

centred at reported position and for text "Off Posn" in

top of the Physical AIS AtoN.

Note: Physical AIS AtoN indicates realtime EPFS

position of drifting AtoN (obstacle).

AIS AtoN indicating Lights

failure

Failure is indicated using yellow caution colour with text

"Unlit" in top of the Physical AIS AtoN.

AIS AtoN indicating Racon

failure

Failure is indicated using yellow caution colour with text

"Racon err" in top of the Physical AIS AtoN



Table 4.3 – Portrayal of AIS AtoN indicating the absence

of a charted Physical AtoN

Type of failure

condition

Symbol

(Virtual)

Description

AIS AtoN indicating the

absence of a charted

Physical AtoN

The absence of a charted AtoN is indicated using

yellow caution colour for both the basic diamond

part of the symbol and for text "Missing". The basic

diamond part is always empty without symbol of

the type of the AtoN.

Note: This case is communicated as a combined

state of "Virtual" and "off position". Type of absent

AtoN can be determined be the underlying charted

object, or selecting the Virtual AIS AtoN Object.



Annex 3

GUIDANCE ON THE IMPLEMENTATION OF MODEL COURSES

Contents

Part1 Preparation

Part 2 Notes on Teaching Technique

Part 3 Curriculum Development

Annex A1 Preparation checklist

Annex A2 Example of a Model Course syllabus in a subject area

Annex A3 Example of a lesson plan for annex A2



Part 1 - Preparation

1 Introduction

1.1 The success of any enterprise depends heavily on sound and effective

preparations.

1.2 Although the IMO model course package has been made as comprehensive as

possible, it is nonetheless vital that sufficient time and resources are devoted to

preparation. Preparation not only involves matters concerning administration or

organization, but also includes the preparation of any course notes, drawings,

sketches, overhead transparencies, etc. which may be necessary.

2 General considerations

2.1 The course package should be studied carefully; in particular, the course

syllabus and associated material must be attentively and thoroughly studied.

This is vital if a clear understanding is to be obtained of what is required, in terms

of resources necessary to successfully implement the course.

2.2 A "checklist", such as that set out in annex Al, should be used throughout all

stages of preparation to ensure that all necessary actions and activities are

being carried out in good time and in an effective manner. The checklist allows

the status of the preparation procedures to be monitored, and helps in identifying

the remedial actions necessary to meet deadlines. It will be necessary to hold

meetings of all those concerned in presenting the course from time to time in

order to assess the status of the preparation and "trouble-shoot" any difficulties.

2.3 The course syllabus should be discussed with the teaching staff who are to

present the course, and their views received on the particular parts they are to

present. A study of the syllabus will determine whether the incoming trainees

need preparatory work to meet the entry standard. The detailed teaching

syllabus is constructed in "training outcome" format. Each specific outcome

states precisely what the trainee must do to show that the outcome has been

achieved. An example of a model course syllabus is given in annex A2. Part 3

deals with curriculum development and explains how a syllabus is constructed

and used.

2.4 The teaching staff who are to present the course should construct notes or

lesson plans to achieve these outcomes. A sample lesson plan for one of the

areas of the sample syllabus is provided in annex A3.

2.5 It is important that the staff who present the course convey, to the person in

charge of the course, their assessment of the course as it progresses.



3 Specific considerations

3.1 Scope of course

In reviewing the scope of the course, the instructor should determine whether it needs any adjustment in order to meet additional local or national requirements (see Part 3).

3.2 Course objective

3.2.1 The course objective, as stated in the course material, should be very carefully considered so that its meaning is fully understood. Does the course objective require expansion to encompass any additional task that national or local requirements will impose upon those who successfully complete the course? Conversely, are there elements included which are not validated by national industry requirements?

3.2.2 It is important that any subsequent assessment made of the course should include a review of the course objectives.

3.3 Entry standards

3.3.1 lf the entry standard will not be met by your intended trainee intake, those entering the course should first be required to complete an upgrading course to raise them to the stated entry level.

Alternatively, those parts of the course affected could be augmented by inserting course material which will cover the knowledge required.

3.3.2 If the entry standard will be exceeded by your planned trainee intake, you may wish to abridge or omit those parts of the course the teaching of which would be unnecessary, or which could be dealt with as revision.

3.3.3 Study the course material with the above questions in mind and with a view to assessing whether or not it will be necessary for the trainees to carry out preparatory work prior to joining the course. Preparatory material for the trainees can range from refresher notes, selected topics from textbooks and reading of selected technical papers, through to formal courses of instruction. It may be necessary to use a combination of preparatory work and the model course material in modified form. It must be emphasized that where the model course material involves an international requirement, such as a regulation of the International Convention on Standards of Training, Certification and Watchkeeping (STCW) 1978, as amended, the standard must not be relaxed; in many instances, the intention of the Convention is to require review, revision or increased depth of knowledge by candidates undergoing training for higher certificates.

3.4 Course certificate, diploma or document

Where a certificate, diploma or document is to be issued to trainees who successfully complete the course, ensure that this is available and properly worded and that the industry and all authorities concerned are fully aware of its purpose and intent.

3.5 Course intake limitations

3.5.1 The course designers have recommended limitations regarding the numbers of trainees who may participate in the course. As far as possible, these limitations should not be exceeded; otherwise, the quality of the course will be diluted.



3.5.2 It may be necessary to make arrangements for accommodating the trainees and providing facilities for food and transportation. These aspects must be considered at an early stage of the preparations.

3.6 Staff requirements

3.6.1 It is important that an experienced person, preferably someone with experience in course and curriculum development, is given the responsibility of implementing the course.

3.6.2 Such a person is often termed a "course co-ordinator" or "course director'. Other staff, such as lecturers, instructors, laboratory technicians, workshop instructors, etc. will be needed to implement the course effectively. Staff involved in presenting the course will need to be properly briefed about the course work they will be dealing with, and a system must be set up for checking the material they may be required to prepare. To do this, it will be essential to make a thorough study of the syllabus and apportion the parts of the course work according to the abilities of the staff called upon to present the work.

3.6.3 The person responsible for implementing the course should consider monitoring the quality of teaching in such areas as variety and form of approach, relationship with trainees, and communicative and interactive skills; where necessary, this person should also provide appropriate counseling and support.

3.7 Teaching facilities and equipment

Rooms and other services

3.7.1 It is important to make reservations as soon as is practicable for the use of lecture rooms, laboratories, workshops and other spaces.

Equipment

3.7.2 Arrangements must be made at an early stage for the use of equipment needed in the spaces mentioned in 3.7.1 to support and carry through the work of the course. For example:

.1 blackboards and writing materials

.2 apparatus in laboratories for any associated demonstrations and experiments

.3 machinery and related equipment in workshops

.4 equipment and materials in other spaces (e.g. for demonstrating fire fighting,

personal survival, etc.).

3.8 Teaching aids

Any training aids specified as being essential to the course should be constructed, or checked for availability and working order.

3.9 Audio-visual aids

Audio-visual aids (AVA) may be recommended in order to reinforce the learning process iri some parts of the course. Such recommendations will be identified in Part A of the model course. The following points should be borne in mind:

.1 Overhead projectors

Check through any illustrations provided in the course for producing overhead projector (OHP) transparencies, and arrange them in order of presentation. To produce transparencies, a supply of transparency sheets is required; the illustrations can be transferred to these via photocopying. Alternatively, transparencies can be



produced by writing or drawing on the sheet. Coloured pens are useful for emphasizing salient points. Ensure that spare projector lamps (bulbs) are available.

.2 Slide projectors

lf you order slides indicated in the course framework, check through them and arrange them in order of presentation. Slides are usually produced from photographic negatives. If further slides are considered necessary and cannot be produced locally, OHP transparencies should be resorted to.

.3 Cine projector

If films are to be used, check their compatibility with the projector (i.e. 16 mm, 35 mm, sound, etc.). The films must be test-run to ensure there are no breakages.

.4 Video equipment

It is essential to check the type of video tape to be used. The two types commonly used are VHS and Betamax. Although special machines exist which can play either format, the majority of machines play only one or the other type. Note that VHS and Betamax are not compatible; the correct machine type is required to match the tape. Check also that the TV raster format used in the tapes (i.e. number of lines, frames/second, scanning order, etc.) is appropriate to the TV equipment available. (Specialist advice may have to be sought on this aspect.) All video tapes should be test-run prior to their use on the course.

.5 Computer equipment

lf computer-based aids are used, check their compatibility with the projector and the available software.

.6 General note

The electricity supply must be checked for voltage and whether it is AC or DC, and every precaution must be taken to ensure that the equipment operates properly and safely. It is important to use a proper screen which is correctly positioned; it may be necessary to exclude daylight in some cases. A check must be made to ensure that appropriate screens or blinds are available. All material to be presented should be test-run to eliminate any possible troubles, arranged in the correct sequence in which it is to be shown, and properly identified and cross-referenced in the course timetable and lesson plans.

3.10 IMO references

The content of the course, and therefore its standard, reflects the requirements of all the relevant IMO international conventions and the provisions of other instruments as indicated in the model course. The relevant publications can be obtained from the Publication Service of IMO, and should be available, at least to those involved in presenting the course, if the indicated extracts are not included in a compendium supplied with the course.

3.11 Textbooks

The detailed syllabus may refer to a particular textbook or textbooks. It is essential that these books are available to each trainee taking the course. lf supplies of textbooks are limited, a copy should be loaned to each trainee, who will return it at the end of the course. Again, some courses are provided with a compendium which includes all or part of the training material required to support the course.



3.12 Bibliography

Any useful supplementary source material is identified by the course designers and listed in the model course. This list should be supplied to the participants so that they are aware where additional information can be obtained, and at least two copies of each book or publication should be available for reference in the training provider's library.

3.13 Timetable

If a timetable is provided in a model course, it is for guidance only. It may only take one or two presentations of the course to achieve an optimal timetable. However, even then it must be borne in mind that any timetable is subject to variation, depending on the general needs of the trainees in any one class and the availability of instructors and equipment.



Part 2 - Notes on Teaching Technique

1 Preparation

1.1 Identify the section of the syllabus which is to be dealt with.

1.2 Read and study thoroughly all the syllabus elements.

1.3 Obtain the necessary textbooks or reference papers which cover the training

area to be presented.

1.4 Identify the equipment which will be needed, together with support staff

necessary for its operation.

1.5 It is essential to use a "lesson plan", which can provide a simplified format for

co-ordinating lecture notes and supporting activities. The lesson plan breaks the

material down into identifiable steps, making use of brief statements, possibly

with keywords added, and indicating suitable allocations of time for each step.

The use of audio-visual material should be indexed at the correct point in there

with an appropriate allowance of time. The audio-visual material should be

test-run prior to its being used in the lecture. An example of a lesson plan is

shown in annex A3.

1.6 The syllabus is structured in training outcome format and it is thereby relatively

straightforward to assess each trainee's grasp of the subject matter presented

during the lecture. Such assessment may take the form of further discussion,

oral questions, written tests or selection-type tests, such as multiple-choice

questions, based on the objectives used in the syllabus. Selection-type tests and

short-answer tests can provide an objective assessment independent of any

bias on the part of the assessor. For certification purposes, assessors should be

appropriately qualified for the particular type of training or assessment.

REMEMBER- POOR PREPARATION IS A SURE WAY TO LOSE THE

INTEREST OF A GROUP

1.7 Check the rooms to be used before the lecture is delivered. Make sure that all

the equipment and apparatus are ready for use and that any support staff are

also prepared and ready. In particular, check that all blackboards are clean and

that a supply of writing and cleaning materials is readily available.

2 Delivery

2.1 Always face the people you are talking to; never talk with your back to the group.

2.2 Talk clearly and sufficiently loudly to reach everyone.

2.3 Maintain eye contact with the whole group as a way of securing their interest

and maintaining it (i.e. do not look continuously at one particular person, nor at

a point in space).



2.4 People are all different, and they behave and react in different ways. An

important function of a lecturer is to maintain interest and interaction between

members of a group.

2.5 Some points or statements are more important than others and should

therefore be emphasized. To ensure that such points or statements are

remembered, they must be restated a number of times, preferably in different

words.

2.6 lf a blackboard is to be used, any writing on it must be clear and large enough

for everyone to see. Use colour to emphasize important points, particularly in

sketches.

2.7 It is only possible to maintain a high level of interest for a relatively short period

of time; therefore, break the lecture up into different periods of activity to keep

interest at its highest level. Speaking, writing, sketching, use of audio-visual

material, questions, and discussions can all be used to accomplish this. When

a group is writing or sketching, walk amongst the group, looking at their work,

and provide comment or advice to individual members of the group when

necessary.

2.8 When holding a discussion, do not allow individual members of the group to

monopolize the activity, but ensure that all members have a chance to express

opinions or ideas.

2.9 lf addressing questions to a group, do not ask them collectively; otherwise, the

same person may reply each time. Instead, address the questions to

individuals in turn, so that everyone is invited to participate.

2.10 It is important to be guided by the syllabus content and not to be tempted to

introduce material which may be too advanced, or may contribute little to the

course objective. There is often competition between instructors to achieve a

level which is too advanced. Also, instructors often strongly resist attempts to

reduce the level to that required by a syllabus.

2.11 Finally, effective preparation makes a major contribution to the success of a

lecture. Things often go wrong; preparedness and good planning will contribute

to putting things right. Poor teaching cannot be improved by good

accommodation or advanced equipment, but good teaching can overcome any

disadvantages that poor accommodation and lack of equipment can present.



Part 3 - Curriculum Development

1 Curriculum

The dictionary defines curriculum as a regular course of study, while syllabus is

defined as a concise statement of the subjects forming a course of study. Thus, in

general terms, a curriculum is simply a course, while a syllabus can be thought of as

a list (traditionally, a list of things to be taught).

2 Course content

The subjects which are needed to form a training course, and the precise skills and

depth of knowledge required in the various subjects, can only be determined

through an in-depth assessment of the job functions which the course participants

are to be trained to perform Job analysis). This analysis determines the training

needs, thence the purpose of the course (course objective). After ascertaining this, it

is possible to define the scope of the course.

(NOTE: Determination of whether or not the course objective has been achieved

may quite possibly entail assessment, over a period of time, of the "on-the-job

performance" of those completing the course. However, the detailed learning

objectives are quite specific and immediately assessable.)

3 Job analysis

A job analysis can only be properly carried out by a group whose members are

representative of the organizations and bodies involved in the area of work to be

covered by the course. The validation of results, via review with persons currently

employed in the job concerned, is essential if undertraining and overtraining are to

be avoided.

4 Course plan

Following definition of the course objective and scope, a course plan or outline can

be drawn up. The potential trainees for the course (the trainee target group) must

then be identified, the entry standard to the course decided and the prerequisites

defined.

5 Syllabus

The final step in the process is the preparation of the detailed syllabus with

associated time scales; the identification of those parts of textbooks and technical

papers which cover the training areas to a sufficient degree to meet, but not exceed,

each learning objective; and the drawing up of a bibliography of additional material

for supplementary reading.



6 Syllabus content

The material contained in a syllabus is not static; technology is continuously

undergoing change and there must therefore be a means for reviewing course

material in order to eliminate what is redundant and introduce new material

reflecting current practice. As defined above, a syllabus can be thought of as a list

and, traditionally, there have always been an "examination syllabus" and a "teaching

syllabus"; these indicate, respectively, the subject matter contained in an

examination paper, and the subject matter an instructor is to use in preparing

lessons or lectures.

7 Training outcomes

7.1 The prime communication difficulty presented by any syllabus is how to convey

the depth of knowledge required. A syllabus is usually constructed as a series

of "training outcomes" to help resolve this difficulty.

7.2 Thus, curriculum development makes use of training outcomes to ensure that a

common minimum level and breadth of attainment is achieved by all the

trainees following the same course, irrespective of the training institution (i.e.

teaching/lecturing staff).

7.3 Training outcomes are trainee-oriented, in that they describe an end result

which is to be achieved by the trainee as a result of a learning process.

7.4 In many cases, the learning process is linked to a skill or work activity and, to

demonstrate properly the attainment of the objective, the trainee response may

have to be based on practical application or use, or on work experience.

7.5 The training outcome, although aimed principally at the trainee to ensure

achievement of a specific learning step, also provides a framework for the

instructor or lecturer upon which lessons or lectures can be constructed.

7.6 A training outcome is specific and describes precisely what a trainee must do to

demonstrate his knowledge, understanding or skill as an end product of a

learning process.

7.7 The learning process is the "knowledge acquisition" or skill development that

takes place during a course. The outcome of the process is an acquired

"knowledge", "understanding", "skill"; but these terms alone are not sufficiently

precise for describing a training outcome.

7.8 Verbs, such as "calculates", "defines", "explains", "lists", "solves" and "states",

must be used when constructing a specific training outcome, so as to define

precisely what the trainee will be enabled to do.

7.9 In the IMO model course project, the aim is to provide a series of model

courses to assist instructors in developing countries to enhance or update the

maritime training they provide, and to allow a common minimum standard to be



achieved throughout the world. The use of training outcomes is a tangible way

of achieving this desired aim.

7.10 As an example, a syllabus in training-outcome format for the subject of ship

construction appears in annex A2. This is a standard way of structuring this

kind of syllabus. Although, in this case, an outcome for each area has been

identified - and could be used in an assessment procedure – this stage is often

dropped to obtain a more compact syllabus structure.

8 Assessment

Training outcomes describe an outcome which is to be achieved by the trainee. Of

equal importance is the fact that such an achievement can be measured

OBJECTIVELY through an evaluation which will not be influenced by the personal

opinions and judgments of the examiner. Objective testing or evaluation provides a

sound base on which to make reliable judgments concerning the levels of

understanding and knowledge achieved, thus allowing an effective evaluation to be

made of the progress of trainees in a course.



Annex A1- Preparation checklist

Ret. Component Identified Reserved Electricity

supply

Purchase

s

Tested Accepted Started Finished Status OK

1 Course plan

2 Timetable

3 Syllabus

4 Scope

5 Objective

6 Entry standard

7 Preparatory

Course

8 Course

certificate

9 Participant

numbers



10 Staffing

Co-ordinator___________________________________________________________________________________________

______

Lecturers____________________________________________________________________________________________

_____

Instructors____________________________________________________________________________________________

_____

Technicians____________________________________________________________________________________________

_____

Other____________________________________________________________________________________________

_____

11

(a)

(b)

Facilities

Rooms

Lab

Workshop

Other

Class

Equipment

Lab

Workshop

Other

_____________________________________________________________________________________________

_____________________________________________________________________________________________

_____________________________________________________________________________________________

_____________________________________________________________________________________________

________________

_____________________________________________________________________________________________

_____________________________________________________________________________________________

_____________________________________________________________________________________________

____________



12 AVA Equipment

and materials

OHP

Slide

Cine

Video

_____________________________________________________________________________________________

_____________________________________________________________________________________________

_____________________________________________________________________________________________

_____________________________________________________________________________________________

________________

13 IMO reference

14 Textbooks

15 Bibliography



Annex A2 - Example of a Model Course syllabus in a

subject area

Subject area: Ship construction

Prerequisite: Have a broad understanding of shipyard practice

General aims: Have knowledge of materials used in shipbuilding,

specification of shipbuilding steel and process of approval

Textbooks: No specific textbook has been used to construct the

syllabus, but the instructor would be assisted in

preparation of lecture notes by referring to suitable books

on ship construction, such as Ship Construction by Eyres

(T12) and Merchant Ship Construction by Taylor (T58).



Course outline

Knowledge, understanding and proficiency Total hours for

each topic

Total hours

for each

subject area of

Required

performance

Competence:

3.1 CONTROL TRIM, STABILITY and STRESS

3.1.1 FUNDAMENTAL PRINCIPLES OF SHIP

CONSTRUCTION, TRIM AND STABILITY

.1 Shipbuilding materials

.2 Welding

.3 Bulkheads

.4 Watertight and weathertight doors

.5 Corrosion and its prevention

.6 Surveys and dry-docking

.7 Stability

3

3

4

3

4

2

83

102



Part C3: Detailed teaching syllabus

Introduction

The detailed teaching syllabus is presented as a series of learning objectives. The

objective, therefore, describes what the trainee must do to demonstrate that the

specified knowledge or skill has been transferred.

Thus each training outcome is supported by a number of related performance

elements in which the trainee is required to be proficient. The teaching syllabus shows

the Required performance expected of the trainee in the tables that follow.

In order to assist the instructor, references are shown to indicate IMO references and

publications, textbooks and teaching aids that instructors may wish to use in preparing

and presenting their lessons.

The material listed in the course framework has been used to structure the detailed

teaching syllabus; in particular:

Teaching aids (indicated by A);

IMO references (indicated by R);and

Textbooks (indicated by T).

will provide valuable information to instructors.

Explanation of information contained in the syllabus tables

The information on each table is systematically organized in the following way. The

line at the head of the table describes the FUNCTION with which the training is

concerned. A function means a group of tasks, duties and responsibilities as specified

in the STCW Code. It describes related activities which make up a professional

discipline or traditional departmental responsibility on board.

The header of the first column denotes the COMPETENCE concerned. Each function

comprises a number of competences. For example, the Function 3, Controlling the

Operation of the Ship and Care for Persons on board at the Management Level,

comprises a number of COMPETENCES. Each competence is uniquely and

consistently numbered in this model course.

In this function the competence is Control trim, stability and stress. It is numbered

3.1; that is the first competence in Function 3. The term "competence" should be

understood as the application of knowledge, understanding, proficiency, skills,

experiences for an individual to perform a task, duty or responsibility on board in a

safe, efficient and timely manner.

Shown next is the required TRAINING OUTCOME. The training outcomes are the

areas of knowledge, understanding and proficiency in which the trainee must be able

to demonstrate knowledge and understanding. Each COMPETENCE comprises a

number of training outcomes. For example, the above competence comprises three

training outcomes. The first is concerned with FUNDAMENTAL PRINCIPLES OF



SHIP CONSTRUCTION, TRIM AND STABILITY. Each training outcome is uniquely

and consistently numbered in this model course. That concerned with fundamental

principles of ship construction, trim and stability is uniquely numbered 3.1.1. For clarity,

training outcomes are printed in black type on grey, for example TRAINING

OUTCOME.

Finally, each training outcome embodies a variable number of Required performances

- as evidence of competence. The instruction, training and learning should lead to the

trainee meeting the specified Required performance. For the training outcome

concerned with fundamental principles of ship construction, trim and stability there are

three areas of performance. These are:

3.1.1.1 Shipbuilding materials

3.1.1.2 Welding

3.1.1.3 Bulkheads

Following each numbered area of Required performance there is a list of activities that

the trainee should complete and which collectively specify the standard of

competence that the trainee must meet. These are for the guidance of instructors and

instructors in designing lessons, lectures, tests and exercises for use in the teaching

process. For example, under the topic 3.1.1.1, to meet the Required performance, the

trainee should be able to:

state that steels are alloys of iron, with properties dependent upon the type

and amounts of alloying materials used;

state that the specifications of shipbuilding steels are laid down by

classification societies;

state that shipbuilding steel is tested and graded by classification society

surveyors who stamp it with approval marks; and so on.

IMO references (Rx) are listed in the column to the right-hand side. Teaching aids (Ax),

videos (Vx) and textbooks (Tx) relevant to the training outcome and required

performances are placed immediately following the TRAINING OUTCOME title.

It is not intended that lessons are organized to follow the sequence of Required

performances listed in the Tables. The Syllabus Tables are organized to match with

the competence in the STCW Code Table A-II/2. Lessons and teaching should follow

college practices. It is nut necessary, for example, for ship building materials to be

studied before stability. What is necessary is that all of the material is covered and that

teaching is effective to allow trainees to meet the standard of the Required

performance.



FUNCTION 3: CONTROLLING THE OPERATION OF THE SHIP AND CARE FOR

PERSONS ON BOARD AT THE MANAGEMENT LEVEL

COMPETENCE 3.1 Control trim, stability and stress IMO reference

3.1.1 FUNDAMENTAL PRINCIPLES OF SHIP

CONSTRUCTION, TRIM AND STABILITY

Textbooks: T11, T12, T35, T58, T69

Teaching aids: A1, A4, V5, V6, V7

Required performance:

1.1 Shipbuilding materials (3 hours)

states that steels are alloys of iron, with properties

dependent upon the type and amounts of alloying materials

used;

states that the specifications of shipbuilding steels are laid

down by classification societies;

states that shipbuilding steel is tested and graded by

classification society surveyors, who stamp it with approval

marks;

explains that mild steel, graded A to E, is used for most parts

of the ship;

states why higher tensile steel may be used in areas Of high

stress, such as the sheer strake;

explains that the use of higher tensile steel in place of mild

steel results in a saving of weight for the same strength;

explains what is meant by:

tensile strength

ductility

hardness

toughness

defines strain as extension divided by original length;

sketches a stress-strain curve for mild steel;

explains:

yield point

ultimate tensile stress

modulus of elasticity

explains that toughness is related to the tendency to brittle

fracture;

R1



explains that stress fracture may be initiated by a small

crack or notch in a plate;

states that cold conditions increase the chances of brittle

fracture;

states why mild steel is unsuitable for the very low

temperatures involved in the containment of liquefied gases;

lists examples where castings or forgings are used in ship

construction;

explains the advantages of the use of aluminium alloys in

the construction of superstructures;

states that aluminium alloys are tested and graded by

classification society surveyors;

explains how strength is preserved in aluminium

superstructures in the event of fire; and

describes the special precautions against corrosion that are

needed where aluminium alloy is connected to steelwork.



Annex A3

Example of a lesson plan for annex A2

Subject area: 3.1 Control trim, stability and stress Lesson number: 1 Duration: 3 hours

Training Area: 3.1.1 Fundamental principles of ship construction, trim and stability

Main element

Specific training outcome in teaching

sequence, with memory keys

Teaching

method

Textbook IMO

reference

A/V aid Instructor

guidelines

Lecture

notes

Time

(minutes)

1.1 Shipbuilding materials (3 hours)

States that steels are alloys of iron, with

properties dependent upon the type and

amounts of alloying materials used

Lecture T12, T58 STCW 11/2,

A-II2

V5 to V7

A1 Compiled

by the

lecturer

10

States that the specifications of shipbuilding

steels are laid down by classification societies


A-II2

V5 to V7

A1 Compiled

by the

lecturer

20

Explains that mild steel, graded A to E, is used

for most parts of the ship


A-II2

V5 to V7

A1 Compiled

by the

15



lecturer

States why higher tensile steel may be used in

areas of high stress, such as the sheer strake


A-II2

V5 to V7

A1 Compiled

by the

lecturer

10

Explains that use of higher tensile steel in

place of mild steel results in a saving of weight

for the same strength


A-II2

V5 to V7

A1 Compiled

by the

lecturer

15



Appendix II: User feedback

In order to ensure the update and validity of this model course, it is essential that the user can provide some feedback. This feedback is useful to develop further training on the safety at sea and marine environment protection. Appendix II gives some specific questions regarding this model course. This appendix also provides the contact information, so that the users can submit the feedback to these questions and make additional comments.

This questionnaire covers three parts as follows:

I. The degree of satisfaction regarding the design of the KUPs of the model course with the IMO references (STCW Convention, SOLAS Convention and Radar Performance Standards);

II. The feedback in the teaching process; and

III. The feedback in the learning process.

It is very important for the developer that the trainees take part in this questionnaire and provide some useful feedback on the learning process.

The degree of satisfaction of the KUPs of in the model course with the IMO references (STCW Convention, SOLAS Convention and radar performance standards)

1. How do you evaluate the items of the "KUP" in the model course? Is there

enough detailed information? Yes or No? Please give answers and justify

your reasons.

2. How do you evaluate whether? Do the KUPs satisfy with the relevant IMO

requirements? If you note any issues, please list them and explain.

3. Are there any other "KUP" items that should be added in the model course?

If so, please list them and explain.

4. Is there any "KUP" that is not required on board in the model course? If so,

please list them and justify.

Feedback in teaching process

1. Is the instructor manual in Part D helpful for your lessons when consulting

Part D of the model course?

2. Are there any difficult points or problems in your teaching process? In what

ways can the model course help you to solve them?

3. Are there any other key points or issues to be added in the teaching

process besides those in Part D of this model course?

4. Do you think there is any necessity to increase the class hours of certain

topics or subtopics in this model course? If so, please specify.



5. Do you know any recent trends or development in the areas to be covered

but not included in this model course? If so, please specify.

6. Are there any ambiguities that cause misunderstanding? If so, please

specify.

Feedbacks in learning process

1. How do you evaluate the course sequence and timetable of this model

course?

2. In the view of trainees, are the sub-items of the required performance

reasonable? If not so, please specify.

3. In the part of "assessment and evaluation", do you think there are any

other effective ways to prove that the trainees have met the competency

requirements?

4. What are the trainees' reflections and feedbacks regarding this model

course? Please give some examples.

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