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Boat Balance - less is more **
In another article on SailJuice, I mention Terry Hutchinson’s approach to boatspeed in the TP52 class, of having a boat that’s easy to sail, even if it’s not the outright fastest. In a similar vein here, we deal with the fallacy that a bigger sail is a faster sail. That is quite often the case, but not always, and boat balance is certainly something you don’t want to compromise in the pursuit of size.
Richard Woof bore this in mind when designing the gennakers for Rob Greenhalgh’s 18-foot skiff RMW, the British boat which beat the Aussie fleet in the JJ Giltinan Tropy, the unofficial class world championship. Greenhalgh’s kites were noticeably smaller and flatter than most of the Aussie kites and yet the yellow boat never lacked for speed. Woofy talks about the importance of designing for shape first and size second, whereas others have opted for hanging the biggest bag between mast and bowsprit that they can get away with.  In the 14 class we have reaches as well as runs in championships courses, partly to stop kite sizes becoming ridiculously oversized. I’m not convinced we’d make our kites any bigger in the 14 even if we just did windward/leeward courses. The same is true of the 470 and Fireball classes where smaller spinnakers are quite often faster than big ones. Skiff designer Julian Bethwaite boils this whole debate down to one word – balance. When designing any boat, Bethwaite is obsessed with tweaking the foil and rig plan until he achieves this magic ingredient. This holds an important lesson for all of us, even us non-technical types who don’t have degrees in naval architecture. It’s a basic lesson in how to sail our boats. Whenever you’re sailing, try experimenting with changing different aspects of your set-up and your technique, and see what works and what doesn’t. But how do you know what’s working and what isn’t? Well, apart from the obvious, of gauging your performance against others in a race or a tuning session, it’s also about looking for the signs of a balanced boat. The clearest and most important sign of boat balance is what you feel through the rudder. A balanced rudder is a good indicator of a healthy set-up. In a strict one-design, especially one like the Laser with just a single sail, you can’t achieve this perfect balance through the rudder as there is inherent weather helm designed into the boat. But on a boat with a mainsail and a jib, you can experiment with different tensions until the boat wants to track in a straight line. I remember on one occasion in the 49er at a Weymouth competition where we were absolutely flying along upwind even though we jammed the jib on as hard as we could and the mainsail was being blown inside out. The slot looked far too choked, but the tiller came into balance and the boat shot forwards. If we eased the jib, the mainsail started behaving better but the tiller felt heavy, and it was slow. On that occasion, having the jib oversheeted was the lesser of two evils. I’m sure we would have been going even faster if we could have worked out a way of having the tiller balanced and the mainsail behaving. Perhaps in retrospect, it might have been letting the jib out on the track to let the slot breathe, or maybe pulling up the daggerboard and using this as a way of depowering. |