Marine Navigation 1: Piloting

Titles in the Fundamentals of Naval Science Series

Seamanship

Marine Navigation 1: Piloting

Marine Navigation 2: Celestial and Electronic

Introduction to Shipboard Weapons

Introduction to Naval Engineering

Marine Navigation 1: Piloting Second Edition

Richard R. Hobbs Commander, U.S. Naval Reserve

Naval Institute Press Annapolis, Maryland

Fundamentals of Naval Science Series

Copyright © 1981, 1974 Softcover reprint of the hardcover 1st edition 1981

by the United States Naval Institute Annapolis, Maryland Third printing 1985, with corrections and revisions

All rights reserved. No part of this book may be reproduced without written permission from the publisher.

Library of Congress Cataloging Publication Data

Hobbs, Richard R. Marine navigation. (Fundamentals of naval science series) Includes index. Contents: -1. Piloting 1. Navigation. 2. Pilots and pilotage.

3. Nautical astronomy. 4. Electronics in naviga­tion. I. Title. II. Series. VK555. H67 1981 623.89 81-9538 ISBN 978-94-011-7372-8 ISBN 978-94-011-7370-4 (eBook)

AACR2

DOI 10.1007/978-94-011-7370-4

To My Parents

Whose guidance set my life on a steady course

Contents

Foreword xi Preface to the Second Edition xiii

Chapter 1 The Art of Navigation 1

2 The Shipboard Navigation Department Organization 4

Duties of the Navigator 4 Relationship of the Navigator to the Command Structure 5 The Navigator's Staff 6

3 The Piloting Team 9

The Navigator and His plotter 10 The Bearing Recorder 10 The Bearing Taker 11 The Radar Operator 12 The Echo Sounder Operator 13 The Piloting Team Routine 14 Conclusion 16

4 The Nautical Chart 17

The Terrestrial Coordinate System 18 Chart Projections 23 Chart Interpretation 26 Determination of Position, Distance, and Direction

on a Mercator Chart 31 Production of Nautical Charts 35 The Chart Numbering System 37 The Chart Correction System 43 Summary 50

5 Navigational Publications 51

Catalog of Nautical Charts, Publication No. l-N 51 NOS Nautical Chart Catalogs 56 Coast Pilots 57 Sailing Directions 60

Fleet Guides 63 Light List 65 List of Lights 67 Tide and Tidal Current Tables 69 Pilot Charts 71 Distance Between Ports, Publication No. 151 71 Almanacs 72 Reference Texts and Manuals 74 Publication Correction System 75 Sum~ry m

6 Visual Navigation Aids 77

Characteristics of Lighted Navigation Aids 78 Identifying a Navigational Light 86 Computing the Visibility of a Light 86 Buoys and Beacons 96 The V.S. Lateral System 97 The IALA Combined Cardinal and Lateral System 104 V se of Buoys and Beacons During Piloting 107 Summary 108

7 Navigational Instruments 110

The Measurement of Direction llO Measurement of Distance ll3 Measurement of Speed ll4 Measurement of Depth ll8 Plotting Instruments 120 Miscellaneous Instruments 124 Summary 130

8 Dead Reckoning 131

Determining the Fix 132 Principles of the Dead Reckoning Plot 137 The Running Fix 140 The Estimated Position 144 The Track 146 Sum~ry M8

9 Shipboard Compasses 151

The Magnetic Compass 151 The Gyrocompass 163 Summary 169

10 Radar 171

Characteristics of a Surface-Search/Navigational Radar 171 The Radar Output Display 173

vIII Contents

Interpretation of a Radarscope Presentation 176 Use of Radar During Piloting 179 Summary 181

11 Tide 183

Causes of Tide 183 Types of Tides 185 Tidal Reference Planes 187 Predicting Height of Tide 189 The Bridge Problem 200 The Shoal Problem 203 Effect of Unusual Meteorological Conditions 204 S~m~ 004

12 Current 206

Ocean Current 206 Tidal Current 209 Wind-driven Currents 230 Summary 231

13 Current Sailing 232

The Estimated Current Triangle 233 Solving the Estimated Current Triangle 234 The Estimated Position Allowing for Current 235 Determining an EP from a Running Fix 236 The Actual Current Triangle 238 Summary 241

14 Precise Piloting and Anchoring 242

Ship's Handling Characteristics 242 Use of Advance and Transfer During Piloting 245 Anchoring 249 Summary 258

15 Voyage Planning 260

TIme WO The Voyage-Planning Process 267 Optimum Track Ship Routing 278 Miscellaneous Considerations 280 S~m~ W2

Appendix A, Chart No.1 285 Appendix B. Abbreviations and Symbols Commonly Used in

Piloting 343 Index 345

Contents ix

Throughout the history of warfare at sea, navigation has been an important basic determinant of victory. Occasionally, new members of the fraternity of the sea will look upon navigation as a chore to be tolerated only as long as it takes to find someone else to assume the responsibility. In my experience, such individuals never make good naval officers. Commander Hobbs has succeeded in bringing together the information and practical skills required for that individual who would take the first step down the road toward becoming a competent marine navigator.

At the outset of this book, the author stresses the necessity for safe navigation, but there is another basic tenet of sea warfare that this book serves. The best weapons system man has ever devised cannot function effectively unless it knows where it is in relation to the real world, where it is in relation to the enemy, and where the enemy is in relation to the real world. Not all defeats can be attributed to this lack of information, but no victories have been won by those who did not know where they were.

w. P. MACK

VICE ADMIRAL, U.S. NAVY

Although these words were written by Admiral Mack for the first edition of this book almost ten years ago, they are certainly no less valid today than they were then. The modern student of navigation could well take the last sentence to heart, not only as it applies to the practice of navigation, but also to life in general.

THE AUTHOR

ANNAPOLIS, 1981

Foreword

Preface to the Second Edition

Marine Navigation 1: Piloting was originally written as a text to introduce midshipmen attending the U.S. Naval Academy and the various NROTC colleges and universities to the shipboard navigation department organization and the principles of piloting as practiced on board ships of the U.S. Navy .. Therefore, the reader will find a definite Navy orientation in much of the material presented in this volume. Nevertheless, because prime emphasis has been placed on setting down the basic knowledge required for the safe navigation of any vessel in piloting waters, most of the information herein will be equally as applicable to navigators of private and commercial craft as to navigators of Navy surface warships.

Piloting refers to the safe navigation of a surface vessel in and near coastal and intracoastal waters. It is done primarily with reference to land and seamarks, as opposed to taking celestial observations or using electronic navigational aids and systems. Most of the piloting tech­niques discussed in this text are not new; in fact, many were developed by early seafarers well before the time of Christ, but modern instru­ments and navigational aids have made attainable a degree of accuracy undreamed of by the ancients. If the inexperienced student navigator can master the time-tested practical techniques of piloting presented in this book, he may be confident that he possesses the basic knowl­edge required to navigate any surface vessel safely in the piloting environment. Moreover, after some practical experience, the student should have sufficient background to proceed on to other more ad­vanced techniques and navigational texts if he so desires.

The subject of navigation at sea beyond piloting waters by use of celestial and electronic navigation is covered in detail in the second volume of this series, entitled Marine Navigation 2: Celestial and Electronic. Its presentation assumes the student will be familiar with the basic techniques and nomenclature introduced in this first vol­ume.

While much of the material presented in Marine Navigation 1 is based upon similar topics covered in standard references such as The American Practical Navigator (Bowditch) and Dutton's Navigation

and Piloting, it is the author's hope that through a logical step-by­step approach, much of the "mystery" associated with the more tech­nical approaches of these and other navigational texts can be elimi­nated. In order that familiarity might be gained with the many pub­lications that support the practice of navigation during piloting, excerpts from many of the navigation publications produced and dis­tributed by the Defense Mapping Agency appear throughout. Wher­ever possible, specific year dates have been deleted from these ex­cerpts and from example problems using them, in order to lessen the sensitivity of this text to the passage of time from the date of publi­cation. When dealing with actual or theoretical problems and situa­tions other than those presented as examples in this text, the student is cautioned to remember always to obtain and use the correct edition covering the specific dates in question.

The author is greatly indebted to Commander F.E. Bassett, USN, who conceived the original edition of this text, and under whose guidance and assistance it was prepared, and to Lieutenant Com­manders J.D.L. Backus, RN; J.L. Roberts, USN; F.A. OIds, USN; and Mr. E.B. Brown of the Defense Mapping Agency, who made many suggestions incorporated in it.

Special thanks for their help with this second edition are gratefully extended to Colonel E.S. Maloney, USMC (Retired), and Colonel W.P. Davis, USA (Retired), for their very thorough review and many suggestions for improvement of the initial draft, and to Lieutenant Commander David Russell, RN, and Lieutenant Commander Royal Connell, USN, of the U.S. Naval Academy Navigation Department, Commander G.F. Hotchkiss, USCG, of the U.S. Coast Guard Acad­emy, Lieutenants T.S. Harden and D. Prince, USN, of the University of Utah NROTC Unit, and Mr. Frank Flyntz of the Maritime Institute of Technology, for their thoughtful suggestions for improvement of several sections, and to Sue Thompson, USNI staff photographer, for several photos of nav aids used herein. Finally, special gratitude is due Beverly Baum, Cynthia Taylor, and Carol Swartz, USNI design manager, assistant designer, and editor, repectively, who have suc­ceeded in creating a superb book in spite of the best efforts of the author. Thanks to you all.

xlv Preface

Marine Navigation 1: Piloting