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Day Skipper revision module 9 of 17
Hand-bearing compass, variation, deviation, and compass conversions.
5 guided lessons · 18 practice questions · 12 flashcards
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True north is the geographic chart reference. Magnetic north is the direction of the Earth's magnetic field at the place and date. The angular difference between true and magnetic is vari...
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Read the compass rose or other current official chart information carefully. A statement such as 2°30′W (2022), decreasing 8′ annually, means the west value reduces by eight minutes each...
Engines, steelwork, speakers, electric currents, tools, phones and other magnetic items can affect a compass. Because the vessel's orientation to the Earth's field changes, both the amoun...
Write C—D—M—V—T on the page and attach a sign to each error: east positive, west negative. From compass to true, Magnetic = Compass + Deviation, then True = Magnetic + Variation. From tru...
Choose conspicuous charted objects with useful crossing angles, identify each before reading, and stand clear of speakers, phones, steel rigging, wiring and the steering compass. Hold the...
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