99-767: Aerotrain may refer to: Aérotrain , a hovercraft train developed in France AeroTrain, an tiltrotor aircraft proposed by Karem Aircraft Aerotrain (GM) , a passenger train built by General Motors Electro-Motive Division AeroTrain (Washington Dulles International Airport) , an automated people mover at Washington Dulles International Airport Aerotrain (KLIA) , an automated people mover in Kuala Lumpur International Airport, Malaysia Aerotrén , an automated people mover at Mexico City International Airport Topics referred to by
198-482: A Royal Navy officer, C.H. Latimer-Needham , who sold his idea to Westland (by then the parent of Saunders-Roe's helicopter and hovercraft interests), and who worked with Cockerell to develop the idea further. The first passenger-carrying hovercraft to enter service was the Vickers VA-3 , which, in the summer of 1962, carried passengers regularly along the north Wales coast from Moreton, Merseyside, to Rhyl . It
297-441: A hovercraft . A ground-effect vehicle needs some forward velocity to produce lift dynamically, and the principal benefit of operating a wing in ground effect is to reduce its lift-dependent drag . The basic design principle is that the closer the wing operates to an external surface such as the ground, when it is said to be in ground effect , the less drag it experiences. An airfoil passing through air increases air pressure on
396-789: A 50-seat passenger GEV named the WSH-500. in 2013 Estonian transport company Sea Wolf Express planned to launch passenger service in 2019 between Helsinki and Tallinn , a distance of 87 km taking only half an hour, using a Russian-built ekranoplan. The company ordered 15 ekranoplans with maximum speed of 185 km/h and capacity of 12 passengers, built by Russian RDC Aqualines. In 2021 Brittany Ferries announced that they were looking into using REGENT (Regional Electric Ground Effect Naval Transport) ground effect craft " seagliders " for cross English Channel services. Southern Airways Express also placed firm orders for seagliders with intent to operate them along Florida's east coast. Around mid-2022,
495-427: A GEV, as compared to an aircraft of similar capacity, will improve its fuel efficiency and, up to a point, its speed. GEVs are also much faster than surface vessels of similar power, because they avoid drag from the water. On the water the aircraft-like construction of GEVs increases the risk of damage in collisions with surface objects. Furthermore, the limited number of egress points make it more difficult to evacuate
594-493: A capacity of 418 passengers and 60 cars. These were later joined by the French-built SEDAM N500 Naviplane with a capacity of 385 passengers and 45 cars; only one entered service and was used intermittently for a few years on the cross-channel service until returned to SNCF in 1983. The service ceased on 1 October 2000 after 32 years, due to competition with traditional ferries, catamarans ,
693-472: A craft was soon recognized, and Alexeyev received support and financial resources from Soviet leader Nikita Khrushchev . Some manned and unmanned prototypes were built, ranging up to eight tonnes in displacement . This led to the development of a 550-tonne military ekranoplan of 92 m (302 ft) length. The craft was dubbed the Caspian Sea Monster by U.S. intelligence experts, after
792-466: A design that relied only on the momentum of the air to provide lift, like a helicopter . In terms of power, a hovercraft would only need between one quarter to one half of the power required by a helicopter. Cockerell built and tested several models of his hovercraft design in Somerleyton, Suffolk, during the early 1950s. The design featured an engine mounted to blow from the front of the craft into
891-775: A fast torpedo boat , the Versuchsgleitboot had a top speed of over 32 knots (59 km/h). It was thoroughly tested and even armed with torpedoes and machine guns for operation in the Adriatic . It never saw actual combat, however, and as the war progressed it was eventually scrapped due to a lack of interest and perceived need, and its engines returned to the air force. The theoretical grounds for motion over an air layer were constructed by Konstantin Eduardovich Tsiolkovskii in 1926 and 1927. In 1929, Andrew Kucher of Ford began experimenting with
990-543: A huge, unknown craft was spotted on satellite reconnaissance photos of the Caspian Sea area in the 1960s. With its short wings, it looked airplane-like in planform, but would probably be incapable of flight. Although it was designed to travel a maximum of 3 m (10 ft) above the sea, it was found to be most efficient at 20 m (66 ft), reaching a top speed of 300–400 knots (560–740 km/h) in research flights. The Soviet ekranoplan program continued with
1089-474: A much higher speed. A GEV is sometimes characterized as a transition between a hovercraft and an aircraft , although this is not correct as a hovercraft is statically supported upon a cushion of pressurized air from an onboard downward-directed fan. Some GEV designs, such as the Russian Lun and Dingo , have used forced blowing under the wing by auxiliary engines to increase the high pressure area under
SECTION 10
#17327766724801188-727: A need for reliable navigation. Minister Ustinov died in 1984, and the new Minister of Defence, Marshal Sokolov , cancelled funding for the program. Only three operational Orlyonok -class ekranoplans (with revised hull design) and one Lun -class ekranoplan remained at a naval base near Kaspiysk . Since the dissolution of the Soviet Union , ekranoplans have been produced by the Volga Shipyard in Nizhniy Novgorod . Smaller ekranoplans for non-military use have been under development. The CHDB had already developed
1287-526: A new form of high-speed land transportation, probably in the field of rail surface travel, for fast trips of distances of up to about 1,600 kilometres (1,000 mi)". In 1959, Ford displayed a hovercraft concept car , the Ford Levacar Mach I . In August 1961, Popular Science reported on the Aeromobile 35B, an air-cushion vehicle (ACV) that was invented by William R. Bertelsen and
1386-471: A number of niche roles where its combination of features were advantageous. Today, they are found primarily in military use for amphibious operations, search-and-rescue vehicles in shallow water, and sporting vehicles. Hovercraft can be powered by one or more engines. Smaller craft, such as the SR.N6 , usually have one engine with the drive split through a gearbox. On vehicles with several engines, one usually drives
1485-604: A number of smaller cylindrical skirts instead of one large one in order to avoid the problems noted above. During the early 1960s he developed a series of prototype designs, which he called "terraplanes" if they were aimed for land use, and "naviplanes" for water. The best known of these designs was the N500 Naviplane , built for Seaspeed by the Société d'Etude et de Développement des Aéroglisseurs Marins (SEDAM). The N500 could carry 400 passengers, 55 cars and five buses. It set
1584-660: A plane; and the Army were 'plain not interested'." This lack of military interest meant that there was no reason to keep the concept secret, and it was declassified. Cockerell was finally able to convince the National Research Development Corporation to fund development of a full-scale model. In 1958, the NRDC placed a contract with Saunders-Roe for the development of what would become the SR.N1 , short for "Saunders-Roe, Nautical 1". The SR.N1
1683-782: A previous period of nearly 10 years of research and development: Bigger concepts are: 25-seater, 32-seater, 60-seater, 80-seater and bigger up to the size of a passenger airplane. Since the 1980s GEVs have been primarily smaller craft designed for the recreational and civilian ferry markets. Germany , Russia and the United States have provided most of the activity with some development in Australia , China , Japan , Korea and Taiwan . In these countries and regions, small craft with up to ten seats have been built. Other larger designs such as ferries and heavy transports have been proposed but have not been carried to completion. Besides
1782-488: A section of a large aerofoil (this creates a low-pressure area above the wing much like an aircraft), the craft was propelled by four aero engines driving two submerged marine propellers, with a fifth engine that blew air under the front of the craft to increase the air pressure under it. Only when in motion could the craft trap air under the front, increasing lift. The vessel also required a depth of water to operate and could not transition to land or other surfaces. Designed as
1881-613: A service to Calais from Dover, which was soon superseded by that of Seaspeed . As well as Saunders-Roe and Vickers (which combined in 1966 to form the British Hovercraft Corporation (BHC)), other commercial craft were developed during the 1960s in the UK by Cushioncraft (part of the Britten-Norman Group) and Hovermarine based at Woolston (the latter being sidewall hovercraft , where the sides of
1980-731: A ship designer whereas Lippisch worked as an aeronautical engineer. The influence of Alexeyev and Lippisch remains noticeable in most GEVs seen today. Led by Alexeyev , the Soviet Central Hydrofoil Design Bureau ( Russian : ЦКБ СПК ) was the center of ground-effect craft development in the USSR. The vehicle came to be known as an ekranoplan ( Russian : экранопла́н , экран screen + план plane , from Russian : эффект экрана , literally screen effect , or ground effect in English). The military potential for such
2079-458: A space below it, combining both lift and propulsion. He demonstrated the model flying over many Whitehall carpets in front of various government experts and ministers, and the design was subsequently put on the secret list. In spite of tireless efforts to arrange funding, no branch of the military was interested, as he later joked, "The Navy said it was a plane not a boat; the RAF said it was a boat not
SECTION 20
#17327766724802178-501: A specialist and insider of German airplane industry from 1963 and a colleague of Alexander Lippisch and Hanno Fischer, was founded with a fundamental knowledge of wing in ground effect physics, as well as results of fundamental tests under different conditions and designs having begun in 1960. For over 30 years, Jörg built and tested 15 different tandem-airfoil flairboats in different sizes and made of different materials. The following tandem-airfoil flairboat (TAF) types had been built after
2277-470: A speed record between Boulogne and Dover of 74 kn (137 km/h). It was rejected by its operators, who claimed that it was unreliable. Another discovery was that the total amount of air needed to lift the craft was a function of the roughness of the surface over which it travelled. On flat surfaces, like pavement, the required air pressure was so low that hovercraft were able to compete in energy terms with conventional systems like steel wheels. However,
2376-409: A suggestion made by his business partner Arthur Ord-Hume. In 1958, he suggested the use of two rings of rubber to produce a double-walled extension of the vents in the lower fuselage. When air was blown into the space between the sheets it exited the bottom of the skirt in the same way it formerly exited the bottom of the fuselage, re-creating the same momentum curtain, but this time at some distance from
2475-698: A walled air cushion vehicle, the Glidemobile . Because the project was classified by the U.S. government, Fletcher could not file a patent. In April 1958, Ford engineers demonstrated the Glide-air, a one-metre (three-foot) model of a wheel-less vehicle that speeds on a thin film of air only 76.2 μm ( 3 ⁄ 1000 of an inch) above its tabletop roadbed. An article in Modern Mechanix quoted Andrew A. Kucher, Ford's vice president in charge of Engineering and Research noting "We look upon Glide-air as
2574-422: Is a vehicle that is able to move over the surface by gaining support from the reactions of the air against the surface of the earth or water. Typically, it is designed to glide over a level surface (usually over the sea) by making use of ground effect , the aerodynamic interaction between the moving wing and the surface below. Some models can operate over any flat area such as frozen lakes or flat plains similar to
2673-536: Is based. However, in 2005, the IMO classified the WISE or GEV under the category of ships. The International Maritime Organization recognizes three types of GEVs: At the time of writing, those classes only applied to craft carrying 12 passengers or more, and (as of 2019) there was disagreement between national regulatory agencies about whether these vehicles should be classified, and regulated, as aircraft or as boats. By
2772-501: Is dangerous because the ground is uneven and the altitude called skimming permits no freedom of maneuver. But on large-sized aircraft, over water, the question may be attempted ..." By the 1960s, the technology started maturing, in large part due to the independent contributions of Rostislav Alexeyev in the Soviet Union and German Alexander Lippisch , working in the United States . Alexeyev worked from his background as
2871-410: Is different from Wikidata All article disambiguation pages All disambiguation pages Hovercraft A hovercraft ( pl. : hovercraft ), also known as an air-cushion vehicle or ACV , is an amphibious craft capable of travelling over land, water, mud, ice, and various other surfaces. Hovercraft use blowers to produce a large volume of air below the hull , or air cushion, that
2970-412: Is more difficult for GEVs with short production runs to overcome. For the vehicle to work, its hull needs to be stable enough longitudinally to be controllable yet not so stable that it cannot lift off the water. The bottom of the vehicle must be formed to avoid excessive pressures on landing and taking off without sacrificing too much lateral stability, and it must not create too much spray, which damages
3069-462: Is slightly above atmospheric pressure . The pressure difference between the higher-pressure air below the hull and lower pressure ambient air above it produces lift, which causes the hull to float above the running surface. For stability reasons, the air is typically blown through slots or holes around the outside of a disk- or oval-shaped platform, giving most hovercraft a characteristic rounded-rectangle shape. The first practical design for hovercraft
Aerotrain - Misplaced Pages Continue
3168-493: Is the classification and legislation to be applied. The International Maritime Organization has studied the application of rules based on the International Code of Safety for High-Speed Craft (HSC code) which was developed for fast ships such as hydrofoils , hovercraft, catamarans and the like. The Russian Rules for classification and construction of small type A ekranoplans is a document upon which most GEV design
3267-565: Is used as a high-speed ferry for up to 47 passengers and 47,500 pounds (21,500 kg) of freight serving the remote Alaskan villages of King Cove and Cold Bay . An experimental service was operated in Scotland across the Firth of Forth (between Kirkcaldy and Portobello, Edinburgh ), from 16 to 28 July 2007. Marketed as Forthfast , the service used a craft chartered from Hovertravel and achieved an 85% passenger load factor . As of 2009 ,
3366-674: The 2007 UK floods . Since 2006, hovercraft have been used in aid in Madagascar by HoverAid, an international NGO who use the hovercraft to reach the most remote places on the island. The Scandinavian airline SAS used to charter an AP1-88 hovercraft for regular passengers between Copenhagen Airport , Denmark, and the SAS Hovercraft Terminal in Malmö , Sweden. In 1998, the US Postal Service began using
3465-465: The Aérotrain . These designs competed with maglev systems in the high-speed arena, where their primary advantage was the very "low tech" tracks they needed. On the downside, the air blowing dirt and trash out from under the trains presented a unique problem in stations, and interest in them waned in the 1970s. By the early 1970s, the basic concept had been well developed, and the hovercraft had found
3564-461: The Levapad concept, metal disks with pressurized air blown through a hole in the centre. Levapads do not offer stability on their own. Several must be used together to support a load above them. Lacking a skirt, the pads had to remain very close to the running surface. He initially imagined these being used in place of casters and wheels in factories and warehouses, where the concrete floors offered
3663-408: The helicopter . Unlike the hydrofoil , it does not have any contact with the surface of the water when in "flight". The ground-effect vehicle constitutes a unique class of transportation. The Boston-based (United States) company REGENT proposed an electric-powered high-wing design with a standard hull for water operations, but also incorporated fore- and aft-mounted hydrofoil units designed to lift
3762-541: The 1920s, the ground effect phenomenon was well-known, as pilots found that their airplanes appeared to become more efficient as they neared the runway surface during landing. In 1934 the US National Advisory Committee for Aeronautics issued Technical Memorandum 771, Ground Effect on the Takeoff and Landing of Airplanes , which was a translation into English of a summary of French research on
3861-571: The Black Sea and Baltic Sea fleets. A few Orlyonoks served with the Soviet Navy from 1979 to 1992. In 1987, the 400-tonne Lun -class ekranoplan was built as an anti-ship missile launch platform. A second Lun , renamed Spasatel , was laid down as a rescue vessel, but was never finished. The two major problems that the Soviet ekranoplans faced were poor longitudinal stability and
3960-589: The British built Hoverwork AP1-88 to haul mail, freight, and passengers from Bethel, Alaska , to and from eight small villages along the Kuskokwim River . Bethel is far removed from the Alaska road system, thus making the hovercraft an attractive alternative to the air based delivery methods used prior to introduction of the hovercraft service. Hovercraft service is suspended for several weeks each year while
4059-554: The English Channel. Hoverlloyd operated from Ramsgate , where a special hoverport had been built at Pegwell Bay, to Calais. Seaspeed operated from Dover, England, to Calais and Boulogne in France. The first SR.N4 had a capacity of 254 passengers and 30 cars, and a top speed of 83 kn (154 km/h). The channel crossing took around 30 minutes and was run like an airline with flight numbers. The later SR.N4 Mk.III had
Aerotrain - Misplaced Pages Continue
4158-663: The FS-8 carried six persons. The FS-8 was to be developed by Fischer Flugmechanik for a Singapore-Australian joint venture called Flightship. Powered by a V8 Chevrolet automobile engine rated at 337 kW, the prototype made its first flight in February 2001 in the Netherlands. The company no longer exists but the prototype craft was bought by Wigetworks, a company based in Singapore and renamed as AirFish 8. In 2010, that vehicle
4257-698: The GEV in a shipyard in southern Iran. The GEV has two engines and no armament. In Singapore, Wigetworks obtained certification from Lloyd's Register for entry into class. On 31 March 2011, AirFish 8-001 became one of the first GEVs to be flagged with the Singapore Registry of Ships, one of the largest ship registries. Wigetworks partnered with National University of Singapore 's Engineering Department to develop higher capacity GEVs. Burt Rutan in 2011 and Korolev in 2015 showed GEV projects. In Korea, Wing Ship Technology Corporation developed and tested
4356-655: The SR.N1 Mk II. A further upgrade with the Armstrong Siddeley Viper produced the Mk III. Further modifications, especially the addition of pointed nose and stern areas, produced the Mk IV. Although the SR.N1 was successful as a testbed, the design hovered too close to the surface to be practical; at 9 inches (23 cm) even small waves would hit the bow. The solution was offered by Cecil Latimer-Needham , following
4455-555: The US Defense Advanced Research Projects Agency (DARPA) launched its Liberty Lifter project, with the goal of creating a low-cost seaplane that would use the ground-effect to extend its range. The program aims to carry 90 tons over 6,500 nautical miles (12,000 km), operate at sea without ground-based maintenance, all using low-cost materials. In May 2024, Ocean Glider announced a deal with UK-based investor MONTE to finance $ 145m of
4554-563: The US/Canadian Great Lakes operate hovercraft for water and ice rescues, often of ice fisherman stranded when ice breaks off from shore. The Canadian Coast Guard uses hovercraft to break light ice. In October 2008, The Red Cross commenced a flood-rescue service hovercraft based in Inverness , Scotland. Gloucestershire Fire and Rescue Service received two flood-rescue hovercraft donated by Severn Trent Water following
4653-847: The United States Defense Advanced Research Projects Agency (DARPA) studied the Aerocon Dash 1.6 wingship . Universal Hovercraft developed a flying hovercraft, first flying a prototype in 1996. Since 1999, the company has offered plans, parts, kits and manufactured ground effect hovercraft called the Hoverwing. Iran deployed three squadrons of Bavar 2 two-seat GEVs in September 2010. This GEV carries one machine gun and surveillance gear, and incorporates features to reduce its radar signature. In October 2014, satellite images showed
4752-400: The ability of hovercraft or hydrofoils, which are closer to the water surface. Like conventional aircraft, greater power is needed for takeoff, and, like seaplanes, ground-effect vehicles must get on the step before they can accelerate to flight speed. Careful design, usually with multiple redesigns of hullforms, is required to get this right, which increases engineering costs. This obstacle
4851-547: The aegis of P & A Campbell, the paddle steamer operators. Operations by Hovertravel commenced on 24 July 1965, using the SR.N6, which carried 38 passengers. Two 98 seat AP1-88 hovercraft were introduced on this route in 1983, and in 2007, these were joined by the first 130-seat BHT130 craft. The AP1-88 and the BHT130 were notable as they were largely built by Hoverwork using shipbuilding techniques and materials (i.e. welded aluminium structure and diesel engines) rather than
4950-506: The aircraft techniques used to build the earlier craft built by Saunders-Roe-British Hovercraft Corporation. Over 20 million passengers had used the service as of 2004 – the service is still operating (as of 2020 ) and is by far the longest, continuously-operated hovercraft service. In 1966, two cross-channel passenger hovercraft services were inaugurated using SR.N6 hovercraft. Hoverlloyd ran services from Ramsgate Harbour, England, to Calais , France, and Townsend Ferries also started
5049-621: The airframe and the engines. The Russian ekranoplans show evidence of fixes for these problems in the form of multiple chines on the forward part of the hull undersides and in the forward location of the jet engines. Finally, limited utility has kept production levels low enough that it has been impossible to amortize development costs sufficiently to make GEVs competitive with conventional aircraft. A 2014 study by students at NASA's Ames Research Center claims that use of GEVs for passenger travel could lead to cheaper flights, increased accessibility and less pollution. One obstacle to GEV development
SECTION 50
#17327766724805148-481: The back to push the craft forward. The British aircraft and marine engineering company Saunders-Roe built the first practical human-carrying hovercraft for the National Research Development Corporation , the SR.N1, which carried out several test programmes in 1959 to 1961 (the first public demonstration was in 1959), including a cross-channel test run in July 1959, piloted by Peter "Sheepy" Lamb, an ex-naval test pilot and
5247-475: The bottom of the craft. Latimer-Needham and Cockerell devised a 4-foot (1.2 m) high skirt design, which was fitted to the SR.N1 to produce the Mk V, displaying hugely improved performance, with the ability to climb over obstacles almost as high as the skirt. In October 1961, Latimer-Needham sold his skirt patents to Westland , who had recently taken over Saunders Roe's interest in the hovercraft. Experiments with
5346-472: The chief test pilot at Saunders Roe. Christopher Cockerell was on board, and the flight took place on the 50th anniversary of Louis Blériot 's first aerial crossing. The SR.N1 was driven by expelled air, powered by a single piston engine. Demonstrated at the Farnborough Airshow in 1960, it was shown that this simple craft can carry a load of up to 12 marines with their equipment as well as
5445-509: The craft out of the water during takeoff run, to facilitate lower liftoff speeds. Used by the Russian Rostislav Alexeyev for his ekranoplan. The wings are significantly shorter than those of comparable aircraft, and this configuration requires a high aft-placed horizontal tail to maintain stability. The pitch and altitude stability comes from the lift slope difference between a front low wing in ground-effect (commonly
5544-409: The development of appropriate design and structural configuration, automatic control and navigation systems have been developed. These include altimeters with high accuracy for low altitude flight and lesser dependence on weather conditions. "Phase radio altimeters " have become the choice for such applications beating laser altimeter , isotropic or ultrasonic altimeters . With Russian consultation,
5643-667: The disappearance of duty-free shopping within the EU, the advancing age of the SR.N4 hovercraft, and the opening of the Channel Tunnel . The commercial success of hovercraft suffered from rapid rises in fuel prices during the late 1960s and 1970s, following conflict in the Middle East. Alternative over-water vehicles, such as wave-piercing catamarans (marketed as the SeaCat in the UK until 2005), use less fuel and can perform most of
5742-695: The eight-seat Volga-2 in 1985, and Technologies and Transport is developing a smaller version called the Amphistar. Beriev proposed a large craft of the type, the Be-2500, as a "flying ship" cargo carrier, but nothing came of the project. In Germany, Lippisch was asked to build a very fast boat for American businessman Arthur A. Collins . In 1963 Lippisch developed the X-112 , a revolutionary design with reversed delta wing and T-tail. This design proved to be stable and efficient in ground effect, and even though it
5841-474: The extra thrust could be directed fore or aft, differentially for rotation. The SR.N1 made its first hover on 11 June 1959, and made its famed successful crossing of the English Channel on 25 July 1959. In December 1959, the Duke of Edinburgh visited Saunders-Roe at East Cowes and persuaded the chief test-pilot, Commander Peter Lamb, to allow him to take over the SR.N1's controls. He flew the SR.N1 so fast that he
5940-413: The fan (or impeller ), which is responsible for lifting the vehicle by forcing high pressure air under the craft. The air inflates the "skirt" under the vehicle, causing it to rise above the surface. Additional engines provide thrust in order to propel the craft. Some hovercraft use ducting to allow one engine to perform both tasks by directing some of the air to the skirt, the rest of the air passing out of
6039-601: The first Local Authority fire service in the UK to operate a hovercraft. It is used to rescue people from thick mud in the Weston-super-Mare area and during times of inland flooding. A Griffon rescue hovercraft has been in use for a number of years with the Airport Fire Service at Dundee Airport in Scotland. It is used in the event of an aircraft ditching in the Tay estuary. Numerous fire departments around
SECTION 60
#17327766724806138-468: The first to demonstrate a practical vehicle in continued use. A memorial to Cockerell's first design stands in the village of Somerleyton . Cockerell came across the key concept in his design when studying the ring of airflow when high-pressure air was blown into the annular area between two concentric tin cans (one coffee and the other from cat food) and a hairdryer. This produced a ring of airflow, as expected, but he noticed an unexpected benefit as well;
6237-444: The hovercraft became an effective transport system for high-speed service on water and land, leading to widespread developments for military vehicles, search and rescue, and commercial operations. By 1962, many UK aviation and shipbuilding firms were working on hovercraft designs, including Saunders Roe/ Westland , Vickers-Armstrong , William Denny , Britten-Norman and Folland . Small-scale ferry service started as early as 1962 with
6336-427: The hovercraft lift system acted as both a lift and a very effective suspension, and thus it naturally lent itself to high-speed use where conventional suspension systems were considered too complex. This led to a variety of " hovertrain " proposals during the 1960s, including England's Tracked Hovercraft and France's Aérotrain . In the U.S., Rohr Inc. and Garrett both took out licences to develop local versions of
6435-784: The hovercraft's marine tasks. Although developed elsewhere in the world for both civil and military purposes, except for the Solent Ryde-to-Southsea crossing, hovercraft disappeared from the coastline of Britain until a range of Griffon Hoverwork were bought by the Royal National Lifeboat Institution . Hovercraft used to ply between the Gateway of India in Mumbai and CBD Belapur and Vashi in Navi Mumbai between 1994 and 1999, but
6534-785: The hull projected down into the water to trap the cushion of air with normal hovercraft skirts at the bow and stern ). One of these models, the HM-2, was used by Red Funnel between Southampton (near the Woolston Floating Bridge ) and Cowes . The world's first car-carrying hovercraft was made in 1968, the BHC Mountbatten class (SR.N4) models, each powered by four Bristol Proteus turboshaft engines. These were both used by rival operators Hoverlloyd and Seaspeed (which joined to form Hoverspeed in 1981) to operate regular car and passenger carrying services across
6633-492: The last commercial line had linked Ōita Airport and central Ōita but was shut down in October 2009. However, the commercial line between Ōita Airport and central Ōita is scheduled to reopen in 2024. Ground effect vehicle A ground-effect vehicle ( GEV ), also called a wing-in-ground-effect (WIGE or WIG ), ground-effect craft , wingship , flarecraft or ekranoplan ( Russian : экранопла́н – "screenglider" ),
6732-480: The launch of the Vickers-Armstrong VA-3. With the introduction of the 254 passenger and 30 car carrying SR.N4 cross-channel ferry by Hoverlloyd and Seaspeed in 1968, hovercraft had developed into useful commercial craft. Another major pioneering effort of the early hovercraft era was carried out by Jean Bertin 's firm in France. Bertin was an advocate of the "multi-skirt" approach, which used
6831-422: The loss of lift at that point, and this led to further pressure on the skirt. After considerable experimentation, Denys Bliss at Hovercraft Development Ltd. found the solution to this problem. Instead of using two separate rubber sheets to form the skirt, a single sheet of rubber was bent into a U shape to provide both sides, with slots cut into the bottom of the U forming the annular vent. When deforming pressure
6930-418: The main wing) and an aft, higher-located second wing nearly out of ground-effect (generally named a stabilizer). Developed by Alexander Lippisch , this wing allows stable flight in ground-effect through self-stabilization. This is the main Class B form of GEV. Tandem wings can have three configurations: Given similar hull size and power, and depending on its specific design, the lower lift-induced drag of
7029-525: The modern features of a lift engine blowing air into a flexible envelope for lift. Kaario's efforts were followed closely in the Soviet Union by Vladimir Levkov, who returned to the solid-sided design of the Versuchsgleitboot . Levkov designed and built a number of similar craft during the 1930s, and his L-5 fast-attack boat reached 70 knots (130 km/h) in testing. However, the start of World War II put an end to his development work. During World War II, an American engineer, Charles Fletcher , invented
7128-455: The much larger wing on a transport aircraft, though it can do this only when close to the earth's surface. Once sufficient speed has built up, some GEVs may be capable of leaving ground effect and functioning as normal aircraft until they approach their destination. The distinguishing characteristic is that they are unable to land or take off without a significant amount of help from the ground effect cushion, and cannot climb until they have reached
7227-570: The only year-round public hovercraft service in the world still in operation serves between the Isle of Wight and Southsea in the UK. Oita Hovercraft is planning to resume services in Oita, Japan in 2024. Although now a generic term for the type of craft, the name Hovercraft itself was a trademark owned by Saunders-Roe (later British Hovercraft Corporation (BHC), then Westland ), hence other manufacturers' use of alternative names to describe
7326-402: The particular wing. This is the primary reason gliders have long wings. Placing the same wing near a surface such as the water or the ground has the same effect as increasing the aspect ratio because the ground prevents wingtip vortices from expanding, but without having the complications associated with a long and slender wing, so that the short stubs on a GEV can produce just as much lift as
7425-420: The pilot and co-pilot with only a slight reduction in hover height proportional to the load carried. The SR.N1 did not have any skirt, using instead the peripheral air principle that Cockerell had patented. It was later found that the craft's hover height was improved by the addition of a skirt of flexible fabric or rubber around the hovering surface to contain the air. The skirt was an independent invention made by
7524-666: The possibility of establishing a permanent service is still under consideration. Since the Channel routes abandoned hovercraft, and pending any reintroduction on the Scottish route, the United Kingdom's only public hovercraft service is that operated by Hovertravel between Southsea ( Portsmouth ) and Ryde on the Isle of Wight . From the 1960s, several commercial lines were operated in Japan, without much success. In Japan
7623-505: The river is beginning to freeze to minimize damage to the river ice surface. The hovercraft is able to operate during the freeze-up period; however, this could potentially break the ice and create hazards for villagers using their snowmobiles along the river during the early winter. In 2006, Kvichak Marine Industries of Seattle , US built, under licence, a cargo/passenger version of the Hoverwork BHT130 . Designated 'Suna-X', it
7722-415: The same term [REDACTED] This disambiguation page lists articles associated with the title Aerotrain . If an internal link led you here, you may wish to change the link to point directly to the intended article. Retrieved from " https://en.wikipedia.org/w/index.php?title=Aerotrain&oldid=1113374855 " Category : Disambiguation pages Hidden categories: Short description
7821-567: The services were subsequently stopped due to the lack of sufficient water transport infrastructure . In Finland, small hovercraft are widely used in maritime rescue and during the rasputitsa ("mud season") as archipelago liaison vehicles. In England, hovercraft of the Burnham-on-Sea Area Rescue Boat (BARB) are used to rescue people from thick mud in Bridgwater Bay . Avon Fire and Rescue Service became
7920-425: The sheet of fast-moving air presented a sort of physical barrier to the air on either side of it. This effect, which he called the "momentum curtain", could be used to trap high-pressure air in the area inside the curtain, producing a high-pressure plenum that earlier examples had to build up with considerably more airflow. In theory, only a small amount of active airflow would be needed to create lift and much less than
8019-428: The skirt design demonstrated a problem; it was originally expected that pressure applied to the outside of the skirt would bend it inward, and the now-displaced airflow would cause it to pop back out. What actually happened is that the slight narrowing of the distance between the walls resulted in less airflow, which in turn led to more air loss under that section of the skirt. The fuselage above this area would drop due to
8118-511: The smoothness required for operation. By the 1950s, Ford showed a number of toy models of cars using the system, but mainly proposed its use as a replacement for wheels on trains, with the Levapads running close to the surface of existing rails. In 1931, Finnish aero engineer Toivo J. Kaario began designing a developed version of a vessel using an air cushion and built a prototype Pintaliitäjä ('Surface Glider'), in 1937. His design included
8217-421: The subject. The French author Maurice Le Sueur had added a suggestion based on this phenomenon: "Here the imagination of inventors is offered a vast field. The ground interference reduces the power required for level flight in large proportions, so here is a means of rapid and at the same time economic locomotion: Design an airplane which is always within the ground-interference zone. At first glance this apparatus
8316-501: The support of Minister of Defence Dmitriy Ustinov . It produced the most successful ekranoplan so far, the 125-tonne A-90 Orlyonok . These craft were originally developed as high-speed military transports and were usually based on the shores of the Caspian Sea and Black Sea . The Soviet Navy ordered 120 Orlyonok -class ekranoplans , but this figure was later reduced to fewer than 30 vessels, with planned deployment mainly in
8415-407: The underside, while decreasing pressure across the top. The high and low pressures are maintained until they flow off the ends of the wings, where they form vortices which in turn are the major cause of lift-induced drag —normally a significant portion of the drag affecting an aircraft. The greater the span of a wing, the less induced drag created for each unit of lift and the greater the efficiency of
8514-738: The vehicle in an emergency. Since most GEVs are designed to operate from water, accidents and engine failure typically are less hazardous than in a land-based aircraft, but the lack of altitude control leaves the pilot with fewer options for avoiding collision, and to some extent that negates such benefits. Low altitude brings high-speed craft into conflict with ships, buildings and rising land, which may not be sufficiently visible in poor conditions to avoid. GEVs may be unable to climb over or turn sharply enough to avoid collisions, while drastic, low-level maneuvers risk contact with solid or water hazards beneath. Aircraft can climb over most obstacles, but GEVs are more limited. In high winds, take-off must be into
8613-407: The vehicles. There have been many attempts to understand the principles of high air pressure below hulls and wings. Hovercraft are unique in that they can lift themselves while still, differing from ground effect vehicles and hydrofoils that require forward motion to create lift. The first mention, in the historical record of the concepts behind surface-effect vehicles, to use the term hovering
8712-422: The wind, which takes the craft across successive lines of waves, causing heavy pounding, stressing the craft and creating an uncomfortable ride. In light winds, waves may be in any direction, which can make control difficult as each wave causes the vehicle to both pitch and roll. The lighter construction of GEVs makes their ability to operate in higher sea states less than that of conventional ships, but greater than
8811-423: The wing to assist the takeoff; however they differ from hovercraft in still requiring forward motion to generate sufficient lift to fly. Although the GEV may look similar to the seaplane and share many technical characteristics, it is generally not designed to fly out of ground effect. It differs from the hovercraft in lacking low-speed hover capability in much the same way that a fixed-wing airplane differs from
8910-436: Was applied to the outside of this design, air pressure in the rest of the skirt forced the inner wall to move in as well, keeping the channel open. Although there was some deformation of the curtain, the airflow within the skirt was maintained and the lift remained relatively steady. Over time, this design evolved into individual extensions over the bottom of the slots in the skirt, known as "fingers". Through these improvements,
9009-548: Was asked to slow down a little. On examination of the craft afterwards, it was found that she had been dished in the bow due to excessive speed, damage that was never allowed to be repaired, and was from then on affectionately referred to as the 'Royal Dent'. Testing quickly demonstrated that the idea of using a single engine to provide air for both the lift curtain and forward flight required too many trade-offs. A Blackburn Marboré turbojet for forward thrust and two large vertical rudders for directional control were added, producing
9108-478: Was by Swedish scientist Emanuel Swedenborg in 1716. The shipbuilder John Isaac Thornycroft patented an early design for an air cushion ship / hovercraft in the 1870s, but suitable, powerful, engines were not available until the 20th century. In 1915, the Austrian Dagobert Müller von Thomamühl (1880–1956) built the world's first "air cushion" boat ( Luftkissengleitboot ). Shaped like
9207-580: Was derived from a British invention in the 1950s. They are now used throughout the world as specialised transports in disaster relief, coastguard, military and survey applications, as well as for sport or passenger service. Very large versions have been used to transport hundreds of people and vehicles across the English Channel , whilst others have military applications used to transport tanks, soldiers and large equipment in hostile environments and terrain. Decline in public demand meant that as of 2023 ,
9306-577: Was developed during his consultancy period in South Africa. It was a simple and low-cost design of a first 4-seater tandem-airfoil flairboat completely constructed of aluminium. The prototype was in the SAAF Port Elizabeth Museum from 4 July 2007 until 2013, and is now in private use. Pictures of the museum show the boat after some years outside the museum and without protection against the sun. The consultancy of Günther Jörg,
9405-422: Was envisioned to revolutionise the transportation system, with personal hovering self-driving cars that could speed up to 2,400 km/h (1,500 mph). The idea of the modern hovercraft is most often associated with Christopher Cockerell , a British mechanical engineer. Cockerell's group was the first to develop the use of a ring of air for maintaining the cushion, the first to develop a successful skirt, and
9504-458: Was powered by a 450 hp Alvis Leonides engine powering a vertical fan in the middle of the craft. In addition to providing the lift air, a portion of the airflow was bled off into two channels on either side of the craft, which could be directed to provide thrust. In normal operation this extra airflow was directed rearward for forward thrust and blew over two large vertical rudders that provided directional control. For low-speed manoeuvrability,
9603-609: Was powered by two turboprop aero-engines and driven by propellers . During the 1960s, Saunders-Roe developed several larger designs that could carry passengers, including the SR.N2 , which operated across the Solent , in 1962, and later the SR.N6 , which operated across the Solent from Southsea to Ryde on the Isle of Wight for many years. In 1963 the SR.N2 was used in experimental service between Weston-super-Mare and Penarth under
9702-550: Was registered as a ship in the Singapore Registry of Ships. The University of Duisburg-Essen is supporting an ongoing research project to develop the Hoverwing . German engineer Günther Jörg, who had worked on Alexeyev's first designs and was familiar with the challenges of GEV design, developed a GEV with two wings in a tandem arrangement, the Jörg-II. It was the third, manned, tandem-airfoil boat, named "Skimmerfoil", which
9801-664: Was successfully tested, Collins decided to stop the project and sold the patents to the German company Rhein Flugzeugbau (RFB), which further developed the inverse delta concept into the X-113 and the six-seat X-114 . These craft could be flown out of ground effect so that, for example, peninsulas could be overflown. Hanno Fischer took over the works from RFB and created his own company, Fischer Flugmechanik, which eventually completed two models. The Airfisch 3 carried two persons, and
#479520