A conventional boat having a single hull generates a large amount of water drag which reduces its speed. A double or multi-hull boat also faces the same problem with even larger drag. However, there are boats with two or more hulls that move with their hulls a bit higher in water, producing less water resistance and thus increasing their speed.
Catamaran is one such type of multi-hull water craft having two parallel hulls and a mast mounted on the transverse frame that joins the two hulls. Usually made for recreational or racing purposes, catamarans can be powered by wind power or diesel engine.
Catamarans were first invented on the southern coast of India. However, they are now widely used throughout the whole world. Initially, the double hull design of Catamaran was resisted by many ship builders as they were more accustomed to the traditional mono hull design. But with time, catamarans have proved to be the best design for fast moving water crafts, thanks to their high stability and large capacity.
Though the construction of catamaran is based on the same principles as those of a conventional mono-hull, there are few main differences that make the former more stable and speedier.
The salient feature of catamarans is that they are lighter than the conventional mono hulls, mainly because of their thinner hull cross-section. Moreover, the absence of keel counter-weight makes a catamaran lighter in weight. The higher stability of catamaran is provided by a wider beam that allows carrying of more sail area per unit length than that provided by a conventional mono hull. The greater stability allows the catamaran’s sail to stay erect in the wind, thus acquiring more power from it; whereas in conventional mono hulls the sails bend over, reducing the amount of wind power acting on them.
The main drawback of the catamarans is that as they are lighter in weight, it is difficult to turn them when they are directly heading towards the wind direction. This mainly happens because the catamarans are lighter in proportion, which doesn’t allow them to get the right momentum to turn through the wind. However, the right usage of jib sail can tackle the problem easily.
Catamarans because of their designs are also less likely to capsize in the traditional manner; however they have a tendency to trip over forward if the bow moves excessively inside the water because of the downward wind. Though mainly driven by sails, catamarans can be propelled by both diesel engines and wind power.
Types of Catamarans
There are two main types of catamarans, which are classified on the basis of their multi-hull design. They are:
- Regular catamaran
- Open catamaran
A regular catamaran consists of two hulls connected by a framework which is attached to a mast at the center. The open catamaran has the same construction as that of a regular catamaran but comprises of a platform suspended between the two hulls.
There is one more type of catamaran known as hydroairy catamaran, which consist of a construction similar to an open catamaran but has two flotation chambers below each of its two hulls.
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