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1 PREFACE All thanks to ALLAH S.W.T for by His Grace and Mercy, this Quick Reference of Navigation (QR700) has been successfully published. This Navigation-QR is published as a guide and reference to all the officers and staff of the Malaysian Maritime Enforcement Agency (MMEA) that attends courses or training at the Akademi Maritim Sultan Ahmad Shah (AMSAS). This book has been arranged and edited through reference to certain related navigation publications to facilitate it’s readers to understand and refers swiftly and with ease. It also aims to reduce the dependency on other books of references that involve large expenditure to obtain. In addition to that, it serves as a guide to the instructors in disseminating the relevant knowledge to course participants and trainers. In assisting educators and trainees, AMSAS is moving towards publishing various other Quick reference for each subject that is being taught in AMSAS to provide course participants and trainees an easy guide and simple reference. On behalf of the management of AMSAS, I wish to convey my deepest appreciation to those who have put in a lot of effort to produce this QR700. It is hoped that this guidance will benefit all MMEA officers and staff especially those attending courses in AMSAS. With Best Regards, FIRST ADMIRAL (M) DATO’ MOHD TAHA BIN IBRAHIM 66 TABLE OF CONTENTS Page PREFACE CHAPTER 1: POSITION AND DIRECTION ON THE EARTH’S SURFACE 1.1 Longitude and latitude 1-3 1.2 Unit of measurements 4 1.3 Magnetic Variation 4 CHAPTER 2: CHART 2.1 Distinguishing a well surveyed chart 5 2.2 Coordinates and positions 6 2.3 Selection of chart symbols 6 - 7 2.4 Aids to navigation 8 - 9 2.5 Lateral Marks - direction of buoyage 10 - 11 2.6 Cardinal buoys 11 - 12 2.7 Marks indicating isolated dangers 12 2.8 Marks indicating safe water 12 - 13 2.9 Marks for new wrecks 13 - 14 2.10 Special buoys and marks 14 - 15 2.11 Chart symbols 15 2.12 Two distinct types of sea mark are drawn differently 15 - 18 in the chart CHAPTER 3: CHARTWORK 3.1 Position Lines 19 3.2 Fixing 19 3.3 Chart work Planning symbols 20 3.4 Example for Coastal Navigation 21 3.5 Dead Reckoning (D.R) 22 3.6 Clearing bearings 22 - 23 65 CHAPTER 4: THE PILOTAGE PLAN 4.1 Introduction 24 4.2 Selection of the track 25 - 34 4.3 Execution of Pilotage 35 4.4 Error in the Compass and Eliminating the 35 - 37 Cocked Hat 4.5 Tide 37 - 38 4.6 Chart datum and land survey datum 39 - 40 4.7 Anchorage 40 - 46 CHAPTER 5: BLIND PILOTAGE 5.1 Introduction 47 5.2 Blind Pilotage Planning 48 - 51 5.3 Blind Pilotage Execution 51 - 53 5.4 Radar calibration (Index Error) 53 - 54 5.5 Two-mark method 54 - 55 5.5 Three-mark method 55 5.6 Conning and Control Orders 57 - 58 CHAPTER 6: RELATIVE VELOCITY (RELVEL) AND COLLISION AVOIDANCE 6.1 Introduction 59 - 60 6.2 Principles of Relative Velocity 60- 62 6.3 Initial position of ship 62 6.4 Relative movement 63 6.5 The velocity triangle 63 64 6.4 Relative movement When considering relative tracks, do not make the mistake of assuming that a ship points in the direction of her relative track. She is still pointing in the direction of her course, which may be very different. Visually, a ship often appears to move almost sideways, or crabwise, along her relative track. 6.5 Relative velocity triangle Once the relative track and speed of the other ship have been found, a velocity triangle (fig. 17) may be used to give the other ship’s take track and speed. Alternatively, the velocity triangle maybe used to find the relative track once the true track has been determined is known. Fig. 17 63 CHAPTER 1 c. If own ship is obliged to alter course to give way to another, POSITION AND DIRECTION ON THE EARTH’S SURFACE it is important to be able to assess what effect this maneuver will have on the relative track of other ships nearby. For ex- 1.1 Longitude and latitude ample, own ship W may consider altering course 30° to star- board to avoid another ship G. 1.1.1 The earth can be regarded as a spherical object, and since we're dealing with a 3-dimensional shape we need coordinates of a different form than the usual x- and y-axes. Though adding extra z-axes would make sense for submarines, we will most likely be found on the surface of this sphere while using another system of coordinates, that covers our planet with imaginary lines called meridians and parallels, see figure 1. All these lines together provide the grid which enables us to describe any position in longitudes and latitudes. d. The plotted track GJ is G’s true track and speed (300°, 15 knots). It should be noted that this is very different from G’s relative track and speed (208°, 12.7 knots). 6.3 Initial position of ships 1.1.2 The obvious place to divide the Northern and Southern Hem- The initial positions of the ships do not affect the velocity ispheres was the equator. But the division of the Eastern and triangle, which depends only on the tracks and speed of each Western hemispheres was the source of much political tur- ship. However, the initial positions of the two ships will have very moil. Greenwich (Great Britain) won, placing for example The different effects on subsequent events. Suppose that, the other Netherlands in the Eastern and Ireland in the Western Hemi- ship G had started from a position K on a bearing of 028° from sphere. own ship, instead of starting from position G. Her relative track of 208° must then pass through the position of own ship. G is therefore on a collision course. 1 62 6.2.2 Relative track and relative speed 1.1.3 It takes the earth 24 hours for a full rotation of 360°. Thus, every hour we rotate 15° longitude, see figure 2. a. Relative speed is also dependent upon the courses being steered by each ship. For example, if the two ships are steam- 1.1.4 When it is 12:00 UTC (international standard time) - anywhere ing in station with one another on the same course and in the world - it is 12:00 Local Time in Greenwich and 24:00 Lo- speed, then the speed of one ship relative to the other is ze- cal Time at the other side of the planet: 180° E or 180° W: the ro. In order to avoid collisions between ships and also to ma- date line. Crossing this special meridian changes not only the neuver ships in company safely, the terms relative track and hour but also the date. relative speed must be understood. In Fig. ship G is in sight on the starboard bow of own ship on a crossing course. 1.1.5 The North Pole has latitude of 90° N and the South Pole 90° S. If the true bearing between the two ships does not apprecia- The meridians cover twice this angle up to 180° W or E. bly change, then in accordance with Rule 7 of the Internation- Meridians converge at the poles, whereas parallels run parallel al Regulations for Prevent Collisions at Sea, 1972 (the Rule of to each other and never meet. the Road), a risk of collision must be deemed to exist. (In such a case, under Rule 15, own ship W is required to give 1.1.6 All meridians and the equator - the biggest parallel - form great way to ship G.) circles, and the remaining parallels form so-called small circles. A great circle divides the earth in two exact halves. 1.1.7 In figure 3 the position of Boston in the United States is shown using latitude and longitude in degrees, minutes and seconds: 42° 21' 30" N , 71° 03' 37" W Fig. 16 b. If the true bearing of G from W remains steady, then to the Officer of the Watch in W, G must appear to be approaching W along the line GW. In other words, the track of G relative to W (the relative track of G) is GW. The relative speed is that speed at which G is approaching W along the line GW. Fig. 16 illustrates the case of one ship in sight, crossing, and on a steady bearing. The collision avoidance problem is easy to solve because the bearing is steady; the relative track does not have to be computed. 61 2 1.1.8 Most sailors will actually notate seconds in metric fractions of minutes: 42° 21, 5’ N, 71° 03,6' W or 42° 21.5' N , 71° 03.6' W, On small scaled charts we want to be accurate within one minute or one nautical mile. On larger -- scaled charts the accuracy is more likely to be within a tenth of a mile (a cable). 6.2 Principles of Relative Velocity 6.2.1 Relative speed a. Suppose two ships are approaching each other head-on, the speed of each being 20 knots (Fig. 15). 1.1.9 If the earth were a perfect sphere with a circumference of rough- ly 40000 kilometers all great circles - meridians plus the equator - would have the same length and could be used as a distance unit when divided into 360 degrees, or 360° x 60' = 21600' minutes.