Ship Manoeuvring Principles and Pilotage

This book explains how to undertake a wide range of ship manoeuvres. It provides guidance on the stages and potential risks of each manoeuvre and highlights some of the less obvious features that are commonly overlooked. The guidance will allow ship handlers to develop an understanding of ship manoeuvring characteristics and to anticipate how a ship will react in the prevailing conditions.

PREFACE

I decided to write this book as a result of a chance conversation with my colleague, Peter Russell, about the advantages of experience when piloting ships and how much easier it would have been when starting out on our careers as pilots if we had the benefit of the experience we have gained over the years. At the end of our conversation, Peter suggested that I write this book.

Working on the assumption that anyone who is to handle a ship will have the necessary qualifications and will already know the technology and theory. This book is to try and bridge the gap between an experienced ship handler and those with the theory and technology, who are about to start handling ships and want to equip themselves with some ground rules, guides, measures and references to help make them more competent at handling ships.

Experience cannot be learnt, it’s the result of getting things right and getting things wrong, you try not to repeat the things you got wrong, and to remember the things that you got right. The ‘benefits’ of experience can be learnt, written down and handed on and that is what I have chosen to try and do. Of course there is no guarantee it will stop you from making mistakes, no more than I have stopped making mistakes, but let’s hope that you will gain enough from reading this book so that any mistakes you do make will not be big ones.

What is a man who learns nothing from his mistakes? Better still though to learn from other people’s!

A great number of the ideas I have included in this publication are as a result of observation, noting how a ship behaves and then working out how and why it happened that way and after that, seeing if it happens the same way again next time.

At the end of the day, no matter how much you have learnt from reading books or from what you have been taught, nothing can completely take the place of experience. I don’t think even simulators, no matter how realistic they are, and I’ve had quite a lot of experience on them, can take the place of the real thing. Because you do not get that tension, that anxiety and sometimes fear that you have when it is for real and still have to continue doing the job competently. Anyone who has learnt to drive a car will have gone through the same experience, that moment after having passed your driving test when you have your first near-miss, or worse still if you don’t miss; it’s just the same on ships except it all happens a lot slower, as there are no brakes or grip in the water, it just means you have longer to experience the effect and it is bigger, very much bigger.

Paul R Williamson

CHAPTER 1

BASIC SHIP HANDLING. REDUCING A SHIP’S SPEED TO MANOEUVRE AND TURN AROUND

Manoeuvring plan (not passage plan), comparison by ship’s lengths, a standard ship, old and modern designs, reducing a ship’s speed to manoeuvre and turn round, speed indicating instruments and GPS etc

CHAPTER 2

TRANSVERSE THRUST AND TURNING A SHIP SHORT ROUND

Single and twin screws, fixed and CPP, single and twin rudders, left and right handed inward and outward screws convention

CHAPTER 3

CENTRE OF TURN AND SIDEWAYS SLIP

Position of the centre of turn relative to the ship’s speed, sideways slip

CHAPTER 4

THE EFFECT OF WIND AND OTHER EXTERNAL FORCES ON A SHIP

Wind force chart etc, drift caused by the wind on the loaded and light ship and the effect of trim. The wind effect relative to the position of the ship’s centre of turn, on an even keel and trimmed by the stern. The effect of superstructure in the wind. The wind effect due to its relative direction. Additional superstructure wind effects. The Bernoulli effect. Other external forces, including tugs etc

CHAPTER 5

ASSESSING A SHIP FOR MANOEUVRING

Assessing the effect of trim on the ship’s wind force point and wind resistance point and how it will affect manoeuvring a ship, relative to the manoeuvring space available

CHAPTER 6

GENERAL BERTHING AND UNBERTHING GUIDELINES

Berthing a ship in calm conditions allowing safety margins, use of indicating instruments when manoeuvring, berthing in tidal waters, allowing for the transverse thrust, berthing stern to tide, berthing to buoys, why a ship appears to increase speed as it approaches its berth

CHAPTER 7

BERTHING A SHIP USING AN ANCHOR

With a wide tide, onto a weather berth and when berthing with an offshore wind

CHAPTER 8

BERTHING AND UNBERTHING USING TUGS

Conventional and tractor tug capabilities, positioning tugs for unberthing and berthing, girting

CHAPTER 9

THRUSTERS

Transverse thrusters and azimuth units

CHAPTER 10

EXAMPLES AND CALCULATIONS TO APPROACH A BERTH

Planning approach to a berth, (a) a small ship without any aids and (b) a big ship using tugs

CHAPTER 11

MANOEUVRING IN FOG BY RADAR

Assessing the limitations of a radar and determining a radar’s ability, calculating a ship’s speed by radar, allowing for position of radar scanner

CHAPTER 12

ANCHORING A SHIP

Anchoring in an open anchorage, and in a restricted anchorage, choosing a position where to drop the anchor, anchoring a ship using a radar with various presentations

CHAPTER 13

PASSAGE PLANNING

Passage planning inbound and outbound

CHAPTER 14

PORT APPROACHES, AND NAVIGATING NARROW CHANNELS

Allowing for set and drift, overtaking and other manoeuvres, establishing a ship’s identity by VHF, methods for losing a ship’s way quickly, ships sailing before the wind

CHAPTER 15

TUG AND TOW

Piloting a tug and tow on a passage, berthing towed vessels

CHAPTER 16

HANDLING CHARACTERISTICS OF DIFFERENT SHIP SHAPES

Handling differences between narrow deep ships and short beamy ships

CHAPTER 17

TIDAL STREAMS

Spring and neap tides, new and full moon, tidal streams, counter currents and slack water, and their effect on handling ships, the change of direction of tidal streams at high water and low water

CHAPTER 18

SQUAT, INTERACTION, REACTION, DRAG AND GROUNDING

Why and when ships squat and warnings to look for, interaction between ships, reaction between a ship and the bottom, a ship’s loss of speed due to drag. Manoeuvring in shallow water. The effect of pressures caused when manoeuvring a ship with the minimum under keep clearance reaction to grounding

CHAPTER 19

INCIDENTS

Stories of perfectly true incidents that I have experienced that most seafarers would have found difficulty believing

CHAPTER 20

MISCELLANEOUS

Agreeing the ship’s program etc. Giving engine orders and helm orders, care with twin screwed ships with single rudders, giving directions to tugs, checking the gyro compass, steering settings, noting the difference in wind directions when navigating rivers, climbing a pilot ladder and how to board a submarine

CHAPTER 21

FINALLY

The pilot’s responsibilities relative to the ship and to the shore authorities

Captain Paul R Williamson

Paul Williamson came to the Trinity House Pilotage Service in 1969 from a conventional merchant service career and he retired as a senior Port of London pilot in 2000. His career contained a breadth of experience that is difficult to match and his practical shiphandling skills result from his handling of all ship sizes up to and including VLCCs.