Confused about navigating, three ways to get from A to B.
A Dead Reckon (DR), historical, you did the journey and you think you are at B. Direction, distance from the log, how long e.g you went North & travelled at 5 knots for 1 hour - you´re 5 nautical miles further north than you were an hour ago. Then you realised you had tidal set and drift information to hand, when applied to position B you're somewhere else - position C! That´s an Estimated Position (EP) historical.
The thinking Yachtsman plans in advance - A Course to Steer (CTS) clear of any obstructions and safe. He travels from A and gets to B! First he puts on the tidal set and drift at the beginning of his journey, at position A. Once drawn, he applies his dividers, set with appropriate boat speed (1 hour of boat speed for every hour of tide) to the end of the set and drift line. He makes a mark where the dividers cross his intended route. Now measure that angle, convert to magnetic and you have a CTS (Course To Steer).
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