Internationally, in the last ten years, yachting has generally declined in terms of the numbers of boats being raced. This trend, however, has been bucked by the ever increasing number of sport yachts being built and raced world-wide. Why is that?

First of all, for the purpose of this feature, let's define a sport boat. The main feature is, as the name implies, a sporty racing yacht. They generally tend to be between six and eight metres and are more than likely to be road trailerable. They don't fit any rule and there doesn't seem to be an international consensus to define them, but this may come in time as the boats evolve.

And evolve they have. In New Zealand and Australia yachts like the Elliott 5.9, Ross 780 and Jim Young Rocket 780 started the trend. These boats were all performance orientated, fun to sail and fast. The biggest difference these boats displayed compared to their trailer sailor predecessors, was that they tended to plane downwind. Some even, like the Elliott 5.9 had hiking straps and lead bulbs, a trend that set them apart from the main bunch of trailer sailors. To the traditional trailer yachtie these boats were radical and not in keeping with the mainstream. The picture was the same internationally and the evolution, and revolution, of the sport yacht had started.
 The reduction in weight is not the only answer used to justify the cost of a carbon rig, because with them, we can power the boat up so that it's fully loaded in 8 knots of air.

There are two developments that have advanced the sport boat cause over the past few years: exotic construction materials and asymmetric spinnakers. Both have had a big influence in the evolution of these boats.

John Spencer pioneered the use of plywood in many small craft and many early boats were moulded using polyester resins; both types of construction were strong and light for their day, but in terms of performance, they were limiting materials. Then along came the Gougeon brothers from the USA who pioneered the use of cedar-cored hulls. This was a real breakthrough in terms of providing a means for amateur builders to build a light yet strong boat in the garage.

This method is still used today to produce my T650 and T750 designs. These boats are competitive with the most exotic boats produced and, in ten years, they have only changed in terms of construction by the use of strategically placed carbon fibre in high stress areas (to reduce weight).



Materials such as high strength E-glass, Kevlar and carbon fibre, used in conjunction with epoxy resins, have allowed us to design lighter boats with more lead ballast. This has further allowed the hull shapes to follow more closely the dinghy style of design rather than the traditional trailer sailor shapes.

Another contributing performance factor has come from the use of carbon fibre masts that are about three times the cost and half the weight of an equivalent aluminium section. The reduction in weight is not the only answer used to justify the cost of a carbon rig, because with them, we can power the boat up so that it's fully loaded in 8 knots of air. As the breeze increases, the mast falls off at the top and this exhausts the increased airflow, allowing full sail to be carried in 25 knots of wind. A lot of these boats also carry larger mainsail roaches that also help to exhaust the mainsail in a breeze, as long as the mast is working properly.

For me the introduction of the asymmetric spinnaker has put fun back in to yachting. It is the single most important development that provides the fun aspect of a modern sports boat. Most people wonder how an asymmetric spinnaker can be efficient downwind when the gybe-angles are so large. Yes, they do cover a lot of ground, but it is all fun miles at speed. Sometimes it may be as efficient to carry a spinnaker but the reduction in the hassle factor is a real bonus. Asymmetric spinnakers are not as efficient downwind but we tend to be able to make up for that in some way by increasing the size of the spinnakers and designing boats that are easily driven. Across the breeze they come into their own and an asymmetric spinnaker is definitely a plus. They are extremely forgiving, allow a helmsman a wider arc of sailing and the open back of the sail reduces healing movement.

Asymmetric spinnakers are extremely forgiving, allow a helmsman a wider arc of sailing and the open back of the sail reduces healing movement.
Steve Thompson will continue this series next month when he examines the design aspects of sport boats. Follow-up articles will include, construction, rig setup, sailing with asymmetric spinnakers and tuning. Steve runs Thompson Performance Design and he has many sport yachts sailing around the globe. His contacts are: PO Box 34-540, Birkenhead, Auckland, Phone 09 419 6032.

All of these trends have helped put back the fun into yachting. A modern sport yacht is safe, exhilarating and fun to sail. They don't have to be expensive to build, but certainly can be if there is no budget to worry about.

So what will the future bring? I see a development period lasting another five years. I don't mean development in terms of hull shape, but more the development of classes within the sport boat scene. We have recently seen the addition of trapezes and hiking racks on some boats and this will continue until there are enough of a particular type of boat to form a class.
Europe has really embraced the sport boat, with the formation of a sport boat rule and classes forming in different countries. Australia s well ahead of New Zealand as far as organisation is concerned, but that is about to change with the formation of a New Zealand association to create and foster national classes.

I predict there will be an international sport boat class defined during the next five years and we will see a number of boats from Down-Under competing in the international arena. Sport boats will grow and continue to grow because they really do put affordable fun back into sailing.