You are underway and intend to make good a course of 040°T. You experience a current with a set and drift of 190°T at 1.4 knots, and a northwest wind produces a leeway of 3°. You adjust your course to compensate for the current and leeway, while maintaining an engine speed of 10 knots. What will be your speed made good over your intended course of 040°T?
• Vector triangle of ship’s speed, current, and course made good • Effect of set and drift on speed along the intended track • How leeway changes your heading but not your engine speed
• Draw a velocity triangle: one vector for the ship through the water (10 knots with leeway applied), one for the current (1.4 knots at 190°T). What does their combined (resultant) vector look like relative to 040°T? • Ask yourself: does the current mostly help, mostly oppose, or mostly act sideways to your intended track of 040°T, given its direction of 190°T? How will that affect your speed made good? • Compare your final speed along 040°T with your engine speed of 10 knots. Should the speed made good be slightly less than, much less than, or slightly more than 10 knots?
• Be clear which angle belongs to set of current (190°T) versus course to steer / intended course (040°T). • Confirm that leeway changes your heading you must steer, but not the magnitude of your ship’s through‑the‑water speed (still 10 knots). • When you resolve the resultant velocity, double‑check that you are taking the component along 040°T as your speed made good, not the total magnitude of the combined vector.
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