form fit

Big Pimpin’
cabon-seahorseMany of the most elegant developments in composite racing equipment historically emerge from the fastest small boat classes. A relatively young UK group of carbon specialists are currently showing how it’s done…
As the development of modern dinghies and yachts continues to progress so sailing speeds increase and fleets become tighter. Gains are harder to find but arguably more important. As well as reducing hull weights, increasing righting moments and improving foils, another big chunk of performance gain has been achieved through rigs and sails. An area that has been ignored, until recently, has been the sail batten. This is probably due to the small gains available vs larger speed gains available elsewhere, but every small gain is now critical.
Moth rigs have evolved a lot over the past 5 years as upwind speeds increase while the need for power downwind is always there. Given the limited sail area on a Moth, 8.25m2, there is a big trade-off between upwind and offwind performance. High upwind speeds produce high AWS numbers, resulting in a very overpowered boat that requires depowering quickly. But turn the corner and maximum horsepower is needed to go low and fast.
Membrane sails are now produced with almost zero broadseam (panel shaping) and only luff round. We then rely on the battens to do most of the work of pushing the sail shape and camber into the desired position. The biggest gains we have made over the past year have been through carefully working with each batten individually, adjusting stiffness and taper position, to achieve the flying shape we want.
Read on.