1. Piloting Course (Inland Navigation) Chapter 4 On the Water SEO – Dave West dwest@voyager.net - 651-429-3840 Instructor – Art Mollica artmollica@usfamily.net - 651-777-0277 United States Power Squadrons ®

2. Slide 2 Any questions on homework from Chapter 3? 1.In plotting a pre-planed course, use the following to represent your intended path: (d) a solid line with the course labeled. WN-Ch 5, pg 61 2.To find a DR position and plot it on a chart you must: (d) calculate the distance from a prior position. SG-Ch 3, ¶ 7 3-8.Calculate and fill in the missing values in the table below: SG-Ch 3, ¶ 20 9.In order to convert a magnetic bearing to a true bearing you must apply variation based on the boat’s position. (a) True. WN-Ch 5, pg 63-64 10. The direction of a bearing is: (c) measured from the boat to the navigational aid. SG-Ch 5, ¶ 11. A starboard beam bearing is a relative bearing at: (c) 90 º from the bow. SG-Ch 3, fig 3-5b&c 3.4.5.6.7.8. Distance5.1nm46nm12.6nm10nm15nm12.9nm Time38mins6hr 34min1hr 7min27min1hr 30min1hr 45min Speed8.1kn7.0kn11.3kn22.0kn10.0kn7.4kn

3. Slide 3 12. A relative bearing is measured from: (c) the bow of the boat. SG-Ch 2, pgs 36-37 13-15. Calculate and fill in the missing values in the table below: SG-Ch 3, ¶ 42 16.A navigation range consists of ____ navigational aids aligned to direct you along a path of water. (b) two. SG-Ch 3, ¶51 Any questions on homework from Chapter 3? 13.14.15. Magnetic Bearing080º300º250º Relative Bearing010º125º022º Magnetic Heading070º175º228º

4. Slide 4 Responsibilities of the Skipper  You are responsible for the safety of Your crew Your boat  You decide on navigation Use the techniques that ensure your safety  The Piloting Course provides the tools It’s up to you to decide how to apply them

5. Slide 5 The Basic Technique  GPS is your primary position sensor  Ship’s Compass for Steering  Seaman’s Eye to keep in touch with surroundings  Hand-Bearing Compass to take bearings  Plot GPS Position at regular intervals (~1hr) Verify position via independent means

6. Slide 6 View from the Water  Study charts so you know what to look for  Learn to recognize ‘on-the-water’ views Navigation Aids Landmarks Land Features  Practice on clear days so you know the landscape when it turns restricted

7. Slide 7 Use GPS as Primary Position Sensor  GPS must be properly set up Chart Datum -- WGS 84 (or other as required) Latitude & Longitude (grid)  Degrees, Minutes, Tenths of Minutes for most coastal charts  Degrees, Minutes, Seconds for many inland charts Magnetic directions (preferred, auto set) Distance and Speed – match the chart  Coastal –Nautical Miles (nm) & Knots (kn)  Great Lakes and inland lakes and rivers –Statute Miles (mi) & Miles per Hour (mph)

8. Slide 8 Use the Compass for Steering  GPS is NOT a compass It provides direction based on movement history Will not work in static situation  Compass is easier to steer with May need to use GPS to get oriented Then, read and follow the compass heading

9. Slide 9 Attributes of a Quality Compass  Repeatability Always returns to the same reading  When returned to the same heading  or, when temporarily diverted using a magnet or metallic object  Damping Turns smoothly on your boat Sail & Powerboat compasses are different  Largest you can afford Easier to read, smoother movement Top reading preferred $50 $200 $1,900

10. Slide 10 Errors Affecting Compasses  Metallic Objects Alter local magnetic fields Can cause compass errors  Current-carrying Wires Create their own magnetic fields Interfere with Earth’s field near compass  Compass Error – called DEVIATION Dependent upon heading of boat Things on your boat can affect compass…

11. © 2004, “The Weekend Navigator” Slide 11 Boat Effects on Compass In one direction the metallic mass may have little effect on the local magnetic field In another direction the metallic mass may have a much greater effect on the local magnetic field

12. Slide 12 Dealing with Deviation  Compass can be adjusted To counteract local deviation Via compensating magnets in compass  Compass Adjusting Recommend a professional adjuster  Residual Deviation Even after compensation – some deviation May need to correct compass readings to magnetic (or vise-versa)

13. Slide 13 Deviation Table  Table of Corrections Ref: WN Ch 28 – Measuring Compass Deviation using GPS

14. © 2004, “The Weekend Navigator” Slide 14TV M D C Correcting True to Compass T rue V ariation D eviation C ompass add West subtract East M M add West subtract East subtract West add East subtract West add East  When converting from True to Compass “West is Best” – add West “East is Least” – subtract East M agnetic

15. Slide 15 Practical Magnetic Compass Use  Typical Compass 5° - graduated increments Read to about 2-3°  Properly corrected compass Residual Deviation typically < 2° Ignore Deviation for moderate runs

16. Slide 16 Fluxgate Compass  Economical Electronic Compass  Uses electronics to sense the magnetic field  Self-compensating automatically builds deviation table automatically applies deviation to reading continuously updates deviation table  Extremely Accurate Typically < 1°

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18. Slide 18 Plotting Magnetic  4 x 15 Plotter uses Grid Lines Measures True not Magnetic Requires TVM conversion  Alternative to using Grid Lines Use Compass Rose Middle scale is oriented to Magnetic Measure using parallel rules Or parallel lines on 4x15 plotter

19. Slide 19 3 Scales on Compass Rose Outer scale aligned with True North Middle scale aligned with Magnetic North Tramontana Ostro Ponente Levante Greco Libeccio Siroco Maestro

20. © 2004, “The Weekend Navigator” Slide 20 Parallel Ruler with the Compass Rose 1.Put pencil tip or divider point on center of compass rose. 2.Mark rose scale at course. (130 º) 3.Align parallel ruler with center of compass rose and course (either magnetic or true. 4.Walk parallel ruler to position.

21. © 2004, “The Weekend Navigator” Slide 21 Rolling Plotter w/the Compass Rose 1.Put pencil tip or divider point on center of compass rose. 2.Mark rose scale at course. (092 ºM) 3.Align rolling plotter with center of compass rose and course (either magnetic or true. 4.Roll plotter to position. THE OUTER SCALE IS READ FROM A MERIDIAN OF LONGITUDE. THE INNER SCALE FROM A PARALLEL OF LATITUDE. 090 270 180 000 080 070 060 050 040 030 020 010 000 260 250 240 230 220 210 209 190 180 100 110 120 130 140 150 160 170 180 280 290 300 310 320 330 340 350 360 170 160 150 140 130 350 340 330 320 310 190 200 210 220 230 010 020 030 040 050

22. Slide 22 Exercise 4-1 C 081M T = 066 V = 015W M = 081 Plotting with rectangular course plotter and parallel ruler using the Compass Rose. Plot a course from G “7” Fl G 4s Main Channel to G “5” Fl G 4s GONG Main Channel. Measure and label the magnetic course using parallel rules and the nearest compass rose.

23. Slide 23 Exercise 4-1 C 081M T = 066 V = 015W M = 081 T = 267 V = 015W M = 282 C 282M Plotting with rectangular course plotter and parallel ruler using the Compass Rose. Plot a course from G “7” Fl G 4s Main Channel to G “5” Fl G 4s GONG Main Channel. Measure and label the magnetic course using parallel rules and the nearest compass rose. Plot a course from R “6” Fl R 4s Main Channel to R “8” I Q R Main Channel using the rectangular course plotter and the nearest compass rose.

24. Slide 24 T = 267 V = 015W M = 282 Exercise 4-1 C 081M C 282M M = 220 V = 015W T = 205 C 220M Plotting with rectangular course plotter and parallel ruler using the Compass Rose. Plot a course from G “7” Fl G 4s Main Channel to G “5” Fl G 4s GONG Main Channel. Measure and label the magnetic course using parallel rules and the nearest compass rose. Plot a course from R “6” Fl R 4s Main Channel to R “8” I Q R Main Channel using the rectangular course plotter and the nearest compass rose. Plot and label a course of 220º magnetic from R “4” Fl R 6s BELL Main Channel using the rectangular course plotter and the nearest compass rose.

25. Slide 25 M = 220 V = 015W T = 205 Exercise 4-1 Plotting with rectangular course plotter and parallel ruler using the Compass Rose. Plot a course from G “7” Fl G 4s Main Channel to G “5” Fl G 4s GONG Main Channel. Measure and label the magnetic course using parallel rules and the nearest compass rose. Plot a course from R “6” Fl R 4s Main Channel to R “8” I Q R Main Channel using the rectangular course plotter and the nearest compass rose. Plot and label a course of 220º magnetic from R “4” Fl R 6s BELL Main Channel using the rectangular course plotter and the nearest compass rose. Plot and label a course of 029º magnetic from G C “1” Perkins Cove using parallel ruler and the nearest compass rose. C 081M C 282M C 220M M = 029 V = 015W T = 014 C 029M

26. Slide 26 Questions ? … Comments

27. Slide 27 Cruise and Homework  Read Chapter 5 – Student Guide  Review Chapter 5 – Weekend Navigator  Do Chapter 4 homework  Do Part I of cruise (next slide)  Next class – 21 February

28. Slide 28 Appendix A – Piloting Cruise