Double-ended
Double-ended ferries have interchangeable bows and sterns, allowing them to shuttle back and forth between two terminals without having to turn around. Well-known double-ended ferry systems include the Staten Island Ferry , Washington State Ferries , Star Ferry , several boats on the North Carolina Ferry System , and the Lake Champlain Transportation Company. Most Norwegian fjord and coastal ferries are double-ended vessels. Some ferries in Sydney, Australia and British Columbia are also double-ended. In 2008, BC Ferries launched three of the largest double-ended ferries in the world.
Hovercraft
Hovercraft were developed in the 1960s and 1970s to carry cars. The largest was the massive SRN4 which carried cars in its centre section with ramps at the bow and stern between England and France. The hovercraft was superseded by catamarans which are nearly as fast and are less affected by sea and weather conditions. Only one service now remains, a foot passenger service between Portsmouth and the Isle of Wight run by Hovertravel.
Hydrofoil
Hydrofoils have the advantage of higher cruising speeds, succeeding hovercraft on some English Channel routes where the ferries now compete against the Eurotunnel and Eurostar trains that use the Channel Tunnel. Passenger-only hydrofoils also proved a practical, fast and relatively economical solution in the Canary Islands but were recently replaced by faster catamaran "high speed" ferries that can carry cars. Their replacement by the larger craft is seen by critics as a retrograde step given that the new vessels use much more fuel and foster the inappropriate use of cars [2] in islands already suffering from the impact of mass tourism.
Catamaran
Catamarans are normally associated with high-speed ferry services. Stena Line operates the largest catamarans in the world, the Stena HSS class, between the United Kingdom and Ireland. These waterjet-powered vessels, displacing 19,638 tonnes, are larger than most catamarans and can accommodate 375 passenger cars and 1,500 passengers. Other examples of these super-sizer catamarans are found in the Brittany Ferries fleet with the Normandie Express and the Normandie Vitesse.
Fast RoPax Ferry
Fast RoPax ferries are conventional ferries with a large garage intake and a relatively large passenger capacity, with conventional diesel propulsion and propellers that sail over 25 knots (46 km/h). Pioneering this class of ferries was Attica Group, when it introduced Superfast I between Greece and Italy in 1995 through its subsidiary company Superfast Ferries.
Pontoon ferry
Pontoon ferries carry vehicles across rivers and lakes and are widely used in less-developed countries with large rivers where the cost of bridge construction is prohibitive. One or more vehicles are carried on a pontoon with ramps at either end for vehicles to drive on and off. Cable ferries (next section) are usually pontoon ferries, but pontoon ferries on larger rivers are motorised and able to be steered independently like a boat.
Foot ferry
Foot ferries are small craft used to ferry foot passengers, and often also cyclists, over rivers. These are either self-propelled craft or cable ferries. Such ferries are for example to be found on the lower River Scheldt in Belgium.
Cable ferry
Very short distances may be crossed by a cable or chain ferry, which is usually a pontoon ferry (see above), where the ferry is propelled along and steered by cables connected to each shore. Sometimes the cable ferry is human powered by someone on the boat. Reaction ferries are cable ferries that use the perpendicular force of the current as a source of power. Examples of a current propelled ferry are the four Rhine ferries in Basel, Switzerland [3] . Cable ferries may be used in fast-flowing rivers across short distances. Cable ferries are referred to in Australia and New Zealand as "punts".
Free ferries operate in some parts of the world, such as at Woolwich in London, England (across the River Thames); in Amsterdam, Netherlands (across the IJ waterway); in New York Harbor, connecting Manhattan to Staten Island; along the Murray River in South Australia, and across many lakes in British Columbia. A cable ferry that charges a toll operates on the Rivière des Prairies between Laval-sur-le-Lac and Île Bizard in Quebec, Canada.
Air ferries
In the 1950s and 1960s, travel on an "air ferry" was possible—aeroplanes, often ex-military, specially equipped to take a small number of cars in addition to "foot" passengers. These operated various routes including between the United Kingdom and Continental Europe. Companies operating such services included Corsair.
The term is also applied to any "ferrying" by air, and is commonly used when referring to airborne military operations.
Docking
Ferry boats often dock at specialized facilities designed to position the boat for loading and unloading, called a ferry slip. If the ferry transports road vehicles or railway carriages there will usually be an adjustable ramp called an apron that is part of the slip. In other cases, the apron ramp will be a part of the ferry itself, acting as a wave guard when elevated and lowered to meet a fixed ramp at the terminus — a road segment that extends partially underwater.
The ferry shown right is ferry MV Magogoni used in Tanzania. It was not possible to build suitable docking facilities and that problem is solved by making the ferry extra manoeuvrable. Four identical engine modules with Schottel pump-jets are used for main propulsion. With her steering propellers rotating round vertical shafts she can be put on any place of the ramp, regardless of stream.
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