One-Design Class Catamarans 215 



each hull is in the shape of a semicircle; and 2. the underwater profile 

 of each hull rises toward both bow and stern. Wetted area is also reduced 

 by lightweight construction, and on some catamarans by having the ex- 

 tension tillers arranged in such a way that the skipper as well as the crew 

 can move his weight forward. 



To increase sailpower for light air, good catamarans do three things 

 simultaneously: 1. they have larger actual sail area; 2. they have full- 

 length battens that give shape to the mainsail even in a calm; and 3. they 

 have a streamlined mast that rotates from tack to tack. 



Speed isn't the only advantage of multihulls. Their tremendous sta- 

 bility in all kinds of weather made sailors take notice. As has already been 

 discussed, a monohull or conventional sailing hull obtains its stability 

 from two factors: displacement and freeboard. As a general rule, the 

 greater the displacement and the higher the freeboard, the more stability 

 the craft has. The multihull, on the other hand, relies almost exclusively 

 on only its wide beam for its self-preservation. It has practically no dis- 

 placement—one of the major reasons that it's able to accelerate so rapidly. 

 It has very little weight and no, or little, freeboard in the ordinary sense 

 of the term. 



If you compare the beam of a 16-foot one-design Comet and the aver- 

 age 16-foot catamaran you'll find that the Comet has a beam of 5 feet 

 and the catamaran 7 feet, 6 inches. In other words, the Comet's beam 

 is a little more than one-third of its length, while the catamaran's beam 

 is very nearly one-half of its length. Not only this, but the outside edges 

 of the catamaran are so much more buoyant than those of a conventional 

 hull. If an ordinary sailboat is heeled to the point where the leeward 

 gunwale goes under the water, the boat's cockpit will start to fill unless 

 it's protected by side decking. You don't have this, worry with a cata- 

 maran since there's no cockpit, in the true sense of the word, to fill. 

 The helmsman and crew, of course, sit on a deck supported between the 

 twin hulls. 



Most catamarans are equipped with a daggertype centerboard. Some 

 catamarans are equipped with drop rudders which can be lowered or 

 raised to the required depth by the helmsman at any time, even while 

 sailing. Other cats have fixed rudders. Both rudders are controlled by a 

 single tiller and can be operated on either side of the craft. 



