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  • A Call to AntarcticaOn March 10, 2009 at 13:43:19 French time, Skipper Rich Wilson and Great American III crossed the finish line at Les Sables d'Olonne. Race time: 121 days, 41 minutes and 19 seconds
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Day 118 - Tacking, mathematically speaking

  • Mar
    07

    It should be understood by all viewers of the Vendee Globe website, that because positions are taken from the boats four times per day, the course shown on the map might bear little or no resemblance to the course actually sailed by the boat. I haven't seen the website in a while, but I would guess that the route that is shown for Great American III shows basically a straight line from the second high that I went around. That is not what has happened.

    Since the second high, we have sailed an absolutely symmetric zig-zag course toward the finish, because the wind at the top of this high pressure system, which is moving precisely exactly at the same speed as we are, is precisely west to east, thus we can only sail 40 degrees on either side of that, and thus not head straight for Les Sables d'Olonne. And given the trigonometry of that (sin 45 degrees = 0.7071), if we are sailing 10 knots on our zig zag, we are in fact only making 7 knots toward France. This is why it is taking us so long to get to Les Sables d'Olonne. And right now, we are only sailing in 10 knots of wind, and making 7 knots of boatspeed, 40 degrees off course, so in fact we are only making 4.9 knots toward the finish. In fact, since we crossed the equator, we have not had the bow actually pointing at the finish.