yacht (From Dutch Jacht meaning "hunt") pron. [Iacht or Iat] was originally defined as a light, fast sailing vessel used by the Dutch navy to pursue pirates and other transgressors around and into the shallow waters of the Low Countries. After its selection by Charles II of England as the vessel of choice to return to Britain from the Netherlands for his restoration, it came to be used to convey important persons.
In later parlance, the definition came to cover a wider range of vessels, almost always in private use (i.e. not used for commercial carriage of cargo or passengers), propelled by sail, power, or both and used for pleasure cruising and/or yacht racing. Often, non-sailing yachts are also referred to as motor yachts, to differentiate them from yachts designed for use with sail power.
In modern use, the term yacht applies to two rather different classes of vessels, sailing yachts and power yachts. Traditionally yachts were differentiated from working ships mainly by purpose - yachts were swift and comfortable conveyances of the wealthy and powerful. It was not until the ascendancy of the steamboat and other types of powerboat that sailing vessels as a class became seen as luxury items. Modern use of the term yacht applies to nearly all sailing vessels, other than sailing dinghies, that are used for yacht racing or for pleasure cruising.
Motor yachts, on the other hand, still retain more of the original sense of power and luxury. Much larger and generally far more expensive than the average sailing yacht, the motor yacht contains sufficient living space for at least several days at sea. Overall length generally starts at over 30 feet (9 m) and goes up to well over a hundred feet (30 m). Luxury yachts, such as the one owned by Larry Ellison, can reach over 450 feet (135m), the size of a small cruise ship. The 412 ft (125 m) Royal Yacht Britannia (a steam yacht) has been retired from service and is now on permanent exhibit at Leith.
A sailing yacht can vary in overall length (Length Over All - LOA, in yachting parlance) from about 6 m (20 feet) to well over 30 m (98 ft), where the distinction between a yacht and a ship become blurred. However, most privately owned yachts fall in the range of about 7 m to 14 m (about 23-46 ft); the cost of building and keeping a yacht rises quickly as length increases. In the US sailors tend to refer to smaller yachts as sailboats, while referring to the general sport of sailing as yachting. (Note: within the limited context of sailboat racing, a yacht is any sailing vessel partaking in a race, regardless of size)
Monohull yachts are typically fitted with a fixed keel or a centerboard (adjustable keel) below the waterline to counterbalance the overturning force of wind on the vessel's sails. By contrast, multihull yachts (a catamaran is an example of this type of vessel) use two or more hulls widely separated from each other to provide a stable base that resists overturning.
Until the 1950s almost all yachts were made of wooden boards, or in a larger yacht, steel but nowadays there is a much wider range of materials. Most common is fibreglass, but steel, aluminium and much less often because of insurance difficulties, ferrocement are used as well. Wood is still used (traditional board based methods as well as modern technologies based on plywood, veneers and epoxy-glues etc.) but wood is mostly used when building an individual boat by a hobbyist or wooden boat purist. At the other extreme, high performance yachts such as those used in the Volvo Ocean Race and the America's Cup are often constructed from carbon fibre.
Modern yachts have efficient sail-plans that allow them to sail into the wind. This capability is the result of a sail plan and hull design (typically a sloop rig) that utilizes Bernoulli's principle to generate lift.
Classification of sailing yachts
Sailing yachts fall into four basic categories: 'Day Sailing', 'Weekender', 'Cruiser' and 'Racer'.
Day Sailing yachts
Day Sailing yachts are usually small sub-6 metre (20 foot) vessels. Sometimes called dinghies, they often have a retractable keel, centerboard, or daggerboard. Day sailing yachts do not have a cabin as they are designed for hourly or daily use and not for overnight journeys.
Weekender yachts are small, sub-9.5 metre (30 foot) vessels. They often have twin-keels or lifting keels. This allows them to operate in shallow waters, and if needed 'dry out' - become beached as the tide falls, the hull shape (or twin-keel layout) allows the boat to sit upright when there is no water. Such boats are designed to undertake short journeys, rarely lasting more than 2 to 3 days (hence their name). Of course, in coastal areas long trips may be undertaken in a series of short hops. Weekenders usually only have a simple cabin, often consisting of a single 'saloon', with bedspace for 2-3 people, and clever use of ergonomics to allow both galley (kitchen) space, seating and space for navigation equipment. There is limited space for large stores of water/food. Weekenders tend to be slower vessels due to their small sail area, and due to their small size they can be overwhelmed by heavy seas. Most are single-mast 'Bermudan sloop' rigged vessels, with a single foresail (of the 'jib' or 'genoa') type and a single mainsail. Some are gaff rigged. The smallest of this type--generally called pocket yachts or pocket cruisers can be trailed on special trailers behind vehicles to transport them by road.
Cruisers are by the far the most common in private usage, making up most of the 7 m to 14 m (23 to 46 ft) range. These vessels can be quite complex in design, as designers try to find a balance between docile handling qualities, interior space, good light-wind performance and on-board comfort. The huge range of such craft, from dozens of builders worldwide make it hard to give a single illustrative description. However, most favour a teardrop-planform hull, with a wide, flat bottom and deep single-fin keel to give good stability. Most are single-mast 'Bermudan sloop' rigged vessels, with a single fore-sail (of the 'jib' or 'Genoa') type and a single mainsail. Spinnaker sails, with huge areas, are often supplied for light wind use. These types are often chosen as family vessels, especially those in the 8 to 12 metre (32 to 40 ft) range. Such a vessel will usually have many rooms below deck. Typically there will be 3 double-berth cabins, a single large saloon (galley, seating and navigation area) and a 'head' (toilet/shower-room). The interior will be finished in wood panelling, with plenty of storage space. Cruisers are quite capable of taking on long-range passages of many thousands of miles, so have large freshwater tanks. Such boats have a cruising speed of around 10 km/h. This basic design is typical of the standard types produced by the major yacht-builders. Most large luxury yachts (15m+, 50 feet+) are also cruisers, but their design varies greatly as they are usually 'one off' designs to the specific needs of the buyer.
Racing yachts try to reduce the wetted surface area (which creates drag) by keeping the hull light whilst having a deep and heavy bulb keel, allowing them to support a tall mast with a great sail area. Modern designs tend to have a very wide beam, with a flat bottom, to provide buoyancy preventing an excessive heel angle. Speeds of up to 40 mph can be obtained in good conditions. Dedicated racing yachts sacrifice crew comfort for speed, having basic accommodation to reduce weight. Depending on the type of race, such a yacht may be crewed by as many as 15 people. At the other extreme there are 'single handed' races, where one person alone must control the yacht. Yacht races may be over a simple course of only a few miles, or epic trans-global contests such as the Global Challenge and Clipper Round the World Race. Ocean racing yachts have very good sea-handling qualities, as they must be able to maintain good speeds in all but the heaviest conditions.
Modern sailing yachts
In recent years, small/medium-sized private yachts have evolved from fairly simple vessels with basic accommodation to sophisticated and luxurious boats. This is largely due to reduced hull-building costs brought about by the introduction of fibre-glass hulls, and increased automation and 'production line' techniques to yacht building, especially in Europe. In recent years the amount of electric equipment used on yachts has increased greatly. Even 20 years ago, it was not common for a 7 m (25 ft) yacht to have electric lighting. Now all but the smallest, most basic yachts have electric lighting, radio and navigation aids such as GPS (Global Positioning System). Yachts around 10 m (33 ft) bring in comforts such as hot water, pressurised water systems, refrigerators etc. Aids such as radar, echo-sounding and autopilot are common. This means that the auxiliary engine now also performs the vital function of powering an alternator to provide electrical power and to recharge the yacht's on-board batteries. For yachts engaged on long-range cruising wind- and solar-powered generators can perform the same function. On the biggest, 30m+ (100 ft) luxury yachts, every modern convenience, from air conditioning to television systems is found. Sailing yachts of this size are often highly automated, with computer-controlled electric winches controlling the sails. Such complexity requires dedicated power-generation systems.