A hydrofoil is a
boatwith wing-like foils mounted on struts below the hull. As the craft increases its speed the hydrofoils develop enough lift for the boat to become foilborne - i.e. to raise the hull up and out of the water. This results in a great reduction in drag and a corresponding increase in speed.
The term "hydrofoil" is also used to refer to the foil itself, especially when the
airfoilprofile has been specifically designed for use in water (such as for a propellerblade).
Since air and water are basically the same at the fluid level, albeit with different levels of viscosity, the hydrofoil and
airfoilcreate lift in identical ways (see Foil (fluid mechanics)). The foil is shaped to move smoothly through the water while displacing some water downwards, creating an upwards force on the foil. This upward force lifts the body of the vessel, decreasing drag and increasing speed. The lifting force eventually balances with the weight of the craft, reaching a point where the hydrofoil no longer lifts out of the water, but remains in equilibrium. Since the force of the waves acts over a smaller area of the hydrofoil, there is a marked decrease in turbulence drag.
Early hydrofoils used V-shape foils. Hydrofoils of this type are known as surface-piercing since portions of the V-shape hydrofoils will rise above the water surface when foilborne. Some modern hydrofoils use inverted T-shape foils which are fully submerged. Fully submerged hydrofoils are less subject to the effects of wave action, and are therefore more stable at sea and are more comfortable for the crew and passengers. This type of configuration, however, is not self-stabilizing. The
angle of attackon the hydrofoils needs to be adjusted continuously in accordance to the changing conditions, a control process that is performed by sensors, computer and active surfaces.
Hydrofoils are now being applied in multiple marine applications.
Between 1899 and 1901, the British boat designer
John I Thornycroftworked on a series of models with a stepped hull and single bow foil. In 1909 his company built a full scale convert|22|ft|m|sing=on long boat, "Miranda III", driven by convert|60|hp|abbr=on engine that rode on a bowfoil and flat stern. The subsequent "Miranda IV" was credited with convert|35|kn|km/h. [http://www.hovercraft-museum.org/musthorn1.html] .
A March 1906 "
Scientific American" article by American hydrofoil pioneer William E. Meacham explained the basic principle of hydrofoils. Alexander Graham Bellconsidered the invention of the "hydroplane" a very significant achievement. After reading this article Bell began to sketch concepts of what is now called a hydrofoil boat. With Casey Baldwin, he began hydrofoil experimentation in the summer of 1908. Baldwin studied the work of the Italian inventor Enrico Forlaniniand began testing models based on his designs. This led him and Bell to the development of hydrofoil watercraft. During Bell's world tour of 1910-1911 he and Baldwin met with Forlanini in Italy. They had rides in the Forlanini hydrofoil boat over Lake Maggiore. Baldwin described it as being as smooth as flying. On returning to Baddeck a number of designs were tried culminating in the HD-4. Using Renaultengines a top speed of 87 km/h (54 mph) was achieved, accelerating rapidly, taking wave without difficulty, steering well and showing good stability. Bell's report to the United States Navy permitted him to obtain two 260 kW (350 horsepower) engines. On September 9, 1919the HD-4 set a world marine speed record of 114 km/h (70.86 mph). This record stood for ten years. A full-scale replica of the HD-4 can be seen in the museum on the Alexander Graham Bell National Historic Site in Baddeck.
First passengers boats
Baron von Schertel worked on hydrofoils prior to and during
World War IIin Germany. After the war Schertel's team was captured by the Russians. As Germany was not authorized to build fast boats, Schertel himself went to Switzerland, where he established the Supramar company. In 1952, Supramar launched the first commercial hydrofoil, PT10 "Freccia d'Oro" (Golden Arrow), in Lake Maggiore, between Switzerland and Italy. The PT10 is of surface-piercing type, it can carry 32 passengers and travel at convert|35|kn|km/h. In 1968, the financier Hussain Najadi acquired the Supramar AG and expanded its operations into Japan, Hong Kong, Singapore, UK, Norway and USA. General Dynamicsof the United States became its licensee, and the Pentagon awarded its first R&D naval research project in the field of supercavitation. Hitachi Shipbuilding of Osaka, Japan, was another licensee of Supramar, as well as many leading ship owners and shipyards in the OECD countries.
From 1952 to 1971, Supramar designed many models of hydrofoils: PT20, PT50, PT75, PT100 and PT150. All are of surface-piercing type, except the PT150 combining a surface-piercing foil forward with a fully-submerged foil in the aft location. Over 200 of Supramar's design were built, most of them by Rodriquez in Italy.
SRI Internationalissued a study on "The Economic Feasibility of Passenger Hydrofoil Craft in U.S. Domestic and Foreign Commerce." [http://ntlsearch.bts.gov/tris/record/tris/00026416.html] Commercial use of hydrofoils in the U.S. first appeared in 1961 when two commuter vessels were commissioned by North American Hydrofoils to service the route from Atlantic Highlands, New Jersey to the financial district of Lower Manhattan. [http://www.foils.org/gallery/enterpr.htm]
The Canadian Navy built and tested a high-speed anti-submarine hydrofoil, the HMCS "Bras d'Or", in the late 1960s, but the program was cancelled due to a shift away from ASW by the Canadian Navy. The "Bras d'Or" was a surface-piercing type which performed well during her trials, reaching a maximum speed of convert|63|kn|km/h.
Soviet Unionexperimented extensively with hydrofoils, constructing hydrofoil river boats and ferrieswith streamlined designs, especially during the 1970s and 1980s. Such vessels include the Raketa (1957) type, followedby the larger Meteor type and the smaller Voskhod type.One of the most successful Soviet designer/inventor in this area was Rostislav Alexeyevwho is considered as father of modern hydrofoil based on his design in 1950's which was world first high-speed hydrofoils.Later, circa 1970's, Rostislav Alexeyev also went further to create world first Ekranoplan.
The U.S. Navy operated combat hydrofoils, such as the "Pegasus" class, from 1977 through 1993. These hydrofoils were fast and well armed, and were capable of sinking all but the largest surface vessels. In their
narcoticsinterdiction role, they were a nightmare for drug runnersFact|date=September 2008, being very fast, and having missiles and guns to stop anything they could not catch, as well as the ability to call in air support.
The Italian Navy has used 6 hydrofoils of the "Nibbio" class from the late 1970s. These were armed with a 76 mm gun, two missiles and were capable of speed up to convert|50|kn|km/h.
ailing and sports
The French experimental
sailpowered hydrofoil " Hydroptère" is the result of a research project that involves advanced engineering skills and technologies. In January 2007, the "Hydroptère" has reached a top speed of 47.2 knots.
A new kayak design, called
Flyak, has hydrofoils that lift the kayak enough to significantly reduce drag, allowing speeds of up to 27 km/h.
In 2001, the Moth dinghy has evolved to a radical foil configuration (Moth Foiler).
Surfers have surfboards with hydrofoils, better suited for big waves further out to sea.
Passengers boats today
Sydney Ferries operated a hydrofoil service between Cirular Quay and Manly. From 1967 to 1991, a regular rapid hydrofoil service was offered alongside the larger, slower ferries. These were manufactured by Rodriquez Cantieri Navali [http://www.rodriquez.it/fastferry/hydrofoils.php] and types in use ranged from the PT20 to RHS160F [http://www.ferriesofsydney.com/ferries5.html]
SeaWorldSan Diego (California) Adventure Park began hydrofoil operations soon after the park opened. Visitors could take a 10-minute, convert|4|mi|km|sing=on round trip into Mission Bay aboard a small fleet of surface-piercing hydrofoils. This popular attraction was halted in the mid-1980s, due to concerns about increasing personal watercrafttraffic in the Bay.
Some operators of hydrofoil include:
TurboJETservice, which speeds passengers across the Pearl River Deltabetween Hong Kongand Macauin less than an hour, with an average speed of 45 knots (83km/h), mainly using Boeing's Jetfoil. Also services Shenzhen, Guangzhouand Kowloon. Operated by Shun Tak-China Travel Ship Management Limited.
* "Cometa" service between Nijneangarsk and
Irkutskon the Lake Baikal.
* "Cometa" service between
* "Meteor" service between
Saint Petersburg, Russiaand the Peterhof, a summer palace of Russian tsars.
* "Meteor" service between
Saint Petersburg, Russiaand the Kronstadt, a strongly fortified Russian seaport town, located on Kotlin Island, near the head of the Gulf of Finland. It lies thirty kilometers west of Saint Petersburg.
* "Meteor", "Raketa" and "Voskhod" hydrofoil types operate all over
Volga, Don and Kama Rivers in Russia.
* "Meteor" hydrofoils are operated by a number of tour operators in
Croatia, mostly for packaged tours, but there are also some scheduled services to islands in Adriatic.
Linda Linebetween Tallinnand Helsinki, using two Morye's Olympias, Ukrainian built and Mercedes-Benzpowered hydrofoils.
* Hydrofoils are regularly operated on the three major Italian Lakes by branches of Ministry Of Transportation: "Navigazione Lago Maggiore" services routes on the
Lake Maggiorebetween Locarnoand Arona, "Navigazione Lago di Como" services routes on the Lake Comoand "Navigazione Lago di Garda" services routes on the Lake Garda. Three units of the Rodriquez RHS150 type operate on each lake, for a total of nine hydrofoils. "Navigazione Lago di Como" still operates the last Rodriquez RHS70 in active service in Italy.
* Former Russian hydrofoils are used in southern Italy for connection with islands of
Lazioand Campania. SNAV has 5 RHS200, RHS160 and RHS150 used in the connections between Naplesand the islands of Capriand Ischia.
* Regular hydrofoil service from
* "Fast Flying Ferries" operated by
Connexxion, provides a regular public transportservice over the North Sea Canalbetween Amsterdam Central Station and Velsen-Zuid in The Netherlands, using Voskhod 2M hydrofoils.
* Hellenic Seaways operate their Flying Dolphins service over many routes in the Aegean, between the Cycladic islands,
Saronic Gulfislands such as Aegina and Poros and Athens.
* "Meteor" (2), "Polesye" (4) and "Voskhod" (3) hydrofoil types operate in
Hungary. MAHART PassNave Ltd. operates scheduled hydrofoil liners between Budapest, Bratislavaand Vienna, inland liners between Budapest and the Danube Bend, and theme cruises to Komárom, Solt, Kalocsa and Mohács.
* Russian hydrofoils of the "Kometa" type operated on the
Bulgarian Black Sea Coastconnecting Varna, Nesebar, Burgas, Sozopol, Primorsko, and Tsarevo, and "Raketa" and "Meteor" models served the Bulgarian Danubeports between Rousseand Vidin. Both services were discontinued in the 1990s but may be reopened.
* Vietnamese "Greenline Company" operates hourly shuttle service between
Ho Chi Minh city, Vung Tauand Con Daoisland. Hydrofoil lines using the Russian-built Meteor type also connect Hai Phong, Ha Longand Mong Caiin North Vietnam, Phan Thietand Phu Quy islandand between Rach Giaand Phu Quoc islandin the South.
*The service between
Busan, South Koreaand Fukuoka, Japanis operated by the two companies. Japanese JR Kyūshū Jet Ferry operates "Beetle" five times a day. Korean Miraejetoperates "Kobee" three to four times a day. All of their fleets are Boeing 929.
*As of February 2008, all of the commercial lines in Japan use Boeing 929. The routes include:
**Sado Kisen operates the route between Sado and Niigata.
**Tōkai Kisen operates "Seven Island", running between
Tokyoand Izu Islands, via Tateyama or Yokosuka. The destinations include Izu Ōshima, Toshima, Niijima, Shikinejima, and Kōzushima. The same ship also liks Atami and Izu Ōshima.
**Kyūshū Yūsen operates the route between Fukuoka, Iki, and the two ports of Tsushima.
**Kyūshū Shōsen operates the route between Nagasaki and the two of
Gotō Islands, namely Fukuejima and Nakadōrijima.
**Kagoshima Shōsen and Cosmo Line operate the various routes between Kagoshima and
Flyak: hydrofoil kayak
Disco Volante (ship)
* [http://www.youtube.com/watch?v=z5UMv57gB0Q Flying Dolphin XXI 3d model]
* [http://www.globalsecurity.org/military/systems/ship/hydrofoil-limits.htm Limitations of hydrofoils]
* [http://www.boeing.com/history/boeing/hydro.html Boeing's Jetfoil]
* [http://www.lindaliini.ee Linda Line - Helsinki to Tallinn line]
* [http://www.turbojet.com.hk Turbojet - Hong Kong to Macau Ferry]
* [http://www.human-powered-hydrofoils.com Human-Powered-Hydrofoils.com]
* [http://www.hydroptere.com/index.php4?lang=EN Hydroptère] Experimental sail powered hydrofoil
* [http://foils.org The International Hydrofoil Society]
* [http://www.classicfastferries.com Classic Fast Ferries Magazine]
* [http://www.kjps.co.jp/english/eindex.html Kawasaki Jetfoil]
* [http://www.rodriquez.it/ Rodriquez Cantieri Navali]
* [http://www.riverships.ru/english/types/?grp=3 Directory of Soviet-made hydrofoils]
* [http://morye.kafa.crimea.ua/ Feodosia shipbuilding company Morye]
* [http://www.volga-shipyard.com/ Volga Shipyard]
* [http://www.mtd.spb.ru/ Marine Technology Development Ltd. Saint Petersburg subsidiary]
* [http://www.mahartpassnave.hu MAHART PassNave Ldt - Hungary]
* [http://www.inventist.com/index.php?option=com_content&task=view&id=10 AquaSkipper]
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Look at other dictionaries:
hydrofoil — [ idrofɔjl ] n. m. • 1955; mot angl. , de foil « feuille, surface plane » ♦ Anglic. Navire rapide dont la coque, munie d ailes portantes, se soulève hors de l eau à grande vitesse. Recomm. offic. HYDROPTÈRE. ● hydroptère ou hydrofoil nom masculin … Encyclopédie Universelle
hydrofoil — 1959, boat that travels through water on wings, short for hydrofoil boat, originally the name of the wings themselves (1920); formed in English from HYDRO (Cf. hydro ) + FOIL (Cf. foil) (n.) … Etymology dictionary
hydrofoil — s. m. 1. Estrutura na parte inferior de uma embarcação, semelhante a uns patins ou planadores, sustentados por uma espécie de braços, para reduzir o atrito com a água. 2. Embarcação rápida, a motor, cujo casco é provido dessa estrutura. •… … Dicionário da Língua Portuguesa
hydrofoil — ► NOUN 1) a boat fitted with structures (known as foils) which lift the hull clear of the water at speed. 2) each of the foils of such a craft … English terms dictionary
hydrofoil — [hī′drə foil΄] n. [ HYDRO + (AIR)FOIL] 1. any of the winglike structures attached to the hull of some watercraft: at a certain speed the hull is lifted above the water and the craft skims along on the hydrofoils at great speeds 2. a craft with… … English World dictionary
Hydrofoil — Hydroptère Pour les articles homonymes, voir Hydroptère (homonymie). Prototype Forlanini 1910 Un hydroptère (d … Wikipédia en Français
hydrofoil — /huy dreuh foyl /, n. 1. Naval Archit. a surface form creating a thrust against water in a direction perpendicular to the plane approximated by the surface. 2. Naut. a. a winglike member having this form, designed to lift the hull of a moving… … Universalium
Hydrofoil — Hy|d|ro|foil [ haɪdrəfɔɪl], das; s, s [engl. hydrofoil, geb. nach aerofoil = Tragfläche, flügel]: engl. Bez. für: Tragflächen , Tragflügelboot. * * * Hydrofoil [ haɪdrəʊfɔɪl] das, (s)/ s, englische Bezeichnung für Tragflügelboot. * * *… … Universal-Lexikon
hydrofoil — UK [ˈhaɪdrəʊˌfɔɪl] / US [ˈhaɪdrəˌfɔɪl] noun [countable] Word forms hydrofoil : singular hydrofoil plural hydrofoils a) a boat with wing shaped pieces fixed to the bottom that lift the boat onto the surface of the water as it starts to travel… … English dictionary
Hydrofoil — Hy|dro|foil [ haidroufɔil] das; [s], s <aus gleichbed. engl. hydrofoil> engl. Bez. für Tragflächenboot … Das große Fremdwörterbuch