Raymarine Marine GPS System manual Vmc Plot Screen

RayTech Navigator User’s Guide

The Vmc Plot screen (Figure 5-21) displays the Velocity Made good on Course toward a specific mark or target. Although similar in concept to Vmg, Vmc is equal-to Vmg only when the bearing to the mark and wind direction are identical. Vmc is used when you expect the wind to change between your present position and the target (primarily in long course racing). In such an instance, it may be a smarter tactical move to sail toward your target at the fastest possible speed, even if that heading isn’t directly toward the target.

To use the Vmc plot, select the Course and True Wind Direction and True Wind Speed to be plotted by clicking on the Course, Twd, and Tws up/down arrows or by entering numbers directly. By default, Course and Twd are initially derived from instrument input, but the screen allows you to change these figures to calculate what happens if the wind or course changes.

Figure 5-21. Vmc Plot Screen

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