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n a final consideration of sail trim, let us review the objective. Be it cruising or racing, thefinal aim of trimming is optimum performance.But optimum performance is not necessarily the result of having what looks like perfectlytrimmed sails. Rather, the sails are trimmed to complement a number of other factors whichaltogether produce optimum performance.How do you gauge the level of your performance when under way? Downwind it is relativelyeasy because the shortest distance between two points is a straight line. Optimum performance is therefore the attainment of a maximum speed which can be measured by instruments.When your destination is directly upwind, however, you are attempting to improve your VMG(Velocity Made Good). Although sophisticated electronic systems will give you some guidestowards your VMG, the very best guide to over all performance is helm balance—the ability ofyour boat to maintain a smooth course on its own, without excessive load needed on the wheel tokeep the boat from turning. This is optimum because it involves the lease amount of drag from the rudder.Sail trim must at all times take into consideration helm balance. In general the trim style we’vereferred to as “power” equates to increased weather helm (boat turning to windward); “pointing” produces less weather helm, and in light wind, can even produce lee helm (boat turning toleeward).For really good performance on the race course, the trimmers—both main and genoa—must beconstantly talking to the helmsman so that each is aware of the helm balance at any time. Thehelmsman should be aiming for a few degrees of weather helm, but not too much load (turningpressure) on the wheel. (figure 9) The trimmer, especially the mainsail trimmer, should be making sure that this load does not become excessive if there is a sudden gust or change in winddirection. The result could be a seriously over-balanced boat.Don’t forget, if everything looks perfect to you as a trimmer but the helmsman says the helm isunbalanced or you’re going slow relative to your competitors, then your sail trim is definitelywrong.The whole trimming sequence should start with an evaluation of the wind condition; more on tothe function required (either pointing or power); then to achievement of sail trim through carefulcontrol; and then be completed with an analysis of the resulting balance and efficiency. Figure 9
The angle of the ruddershuld be 3-4 degrees towindward of thecenterline for bestperformance when sailing upwind.