does wind velosity, light air to medium air change the tacking angle when on a beat ?
I know this is an old thread, but I just ran across it, and I think the conclusion reached by Giu and others is not entirely correct. He is correct when you only consider the limiting factors of the boat's basic geometry, i.e., the sail shape, location of genoa track, length of spreaders, etc. But, generally, boat speed increases with wind velocity. An increase in boat speed increases the efficiency of the keel, and that reduces drift to leeward. Thus, in a lower wind velocity, a boat can't point to the full extent which can theoretically be achieved within the limits of it's basic geometry. As the velocity of the wind increases, and the boat speed increases, the efficiency of the keel increases, and, at some point, the boat is able to point to the full extent which can theoretically be achieved within the limits of it's basic geometry. The boat's optimum tacking angle is determined by it's optimum pointing angle. I think Giu's error was in not factoring in the reduction in the keel's efficiency as boat speed declines.