Charts Scoutcraft Badge
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- Describe at least two of the different types of compasses that are used at sea and explain how a magnetic compass works. Know some of the problems that can occur in using a compass with particular focus on use aboard a vessel, and how to overcome these.
- Explain the difference between and demonstrate the ability to find each of these, both on a chart and at sea:
- True North
- Magnetic North
- Grid North
- Explain the cause and effect of variation.
- Know the relationship between magnetic bearings and true bearings.
- Show where to locate the variation adjustment on a chart and know how to calculate the present variation.
- Demonstrate a working knowledge of bearings and reciprocal bearings by being able to carry out an exercise at while on a boat to determine your position on a chart by the cross bearings' method.
- Carry out the following:
- Explain what a chart is.
- Know the differences between a chart and a map.
- Demonstrate a knowledge of scale.
- Explain why we only measure distance on the latitude scale on a chart.
- Be able to read depth contours on a chart, and explain how contours indicate slopes, gradients and major geographic land and seabed features.
- What are soundings and how are they represented on a chart.
- Using a pair of dividers, correctly measure a distance between 2 points on a chart and determine the actual distance that this represents in nautical miles.
- Demonstrate knowledge of some common charting symbols (IALA region B).
- Explain what is meant by the light characteristics shown on a chart e.g. Fl.G.2s5M.
- On a suitable chart, use a parallel rule to plot a course for a hypothetical voyage of approximately 20 nautical miles with at least 5-way points. Provide your watch keeper with a list of magnetic courses to steer, co-ordinates of the waypoints, and time to steam between each waypoint at a speed of 10 knots over the ground. (SoG).
Requirements in PDF