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Bias at the start & finish lines

From an apparently good start, I get a pretty unpredictable position as I round the windward mark. Unpredictable in the sense that I've no real idea whether I'm going to round in first place (it happens, er, occasionally) or in last place (it, um, also happens...). So I started to mess around with some diagrams and so-called city block metrics.

Is 'C' closest to the mark?

Here we have a nice long start line. To make it all simple, we'll ignore any other boats, the windward mark isn't too far away, the wind is blowing exactly perpendicular to the line, the wind is rock steady, and the line isn't offset to one side or the other. So should we start at position A, B, or C? Put it another way, which boat will get to the mark first? It is pretty clear that boats A and B are equally far away from the mark, and boat C is closest; but make your guess and then check it out here.


2011 Lester Gilbert