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velocity made course (VMC) Abbreviated VMC, this is your speed made good in the direction of the activated target waypoint. If your COG is 20º to the left or right of course to the next waypoint then VMC = SOG x cos (20º). Most navigation programs compute this automatically and display the value. There is not universal usage of this term. In fact, the official NMEA parameter is called waypoint closure velocity (WCV), but that is rarely seen in electronic displays. Some programs use just plain VMG which is velocity made good, but most programs reserve that for velocity made good in the direction of the wind, not the next active waypoint. Indeed those programs might even imply that is the navigation parameter to optimize in a sailboat, whereas in fact the optimum course to the mark is what ultimately gets you there the fastest. Some programs use VMG, but then distinguish between VMG-wind and VMG-course. In short when moving to a new program, the use of this term is one of the first things to clarify. VMC, on the other hand, is universally used as defined above. See also Tricky Terms in Navigation.

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