Kite rig

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Kite rigs are wind-assisted propulsion systems for propelling a vehicle. They differ from conventional sails in that they are flown from kite control lines, not supported by masts.

Contents

Vehicles driven by kites include boats, buggies, and vehicles with snow and ice runners. They may be as simple as a person flying a kite while standing on a specialized skateboard, or be large, complex systems fixed to the vehicle, with powered and automated controls. They have recreational and commercial uses.

Structure

Points of sail with a kite buggy. Buggy Winds.jpg
Points of sail with a kite buggy.

Current kite rigs can be sailed within 50 degrees of the wind. [1] This allows them to sail upwind by tacking.

A power kite is held at an angle to the wind using control lines. Like any other sail, the kite develops lift and drag, pulling the vessel. The vector of the kite's pull is added to the forces produced by the vessel (water resistance against the hull, force of wheels against the ground, etc.) to move the vessel in the desired direction.

Windspeed increases with height, allowing kites to develop substantially more thrust per unit area than a conventional sail. Winds are also steadier and less turbulent higher up.

Kites may be adjusted with respect to the wind, manually or by an automated system. A kite cannot stay aloft when there is no wind, and must be re-launched.

Applications

Solo sports

A kitesurfer off Long Beach, California, USA LBKiteSurf09.JPG
A kitesurfer off Long Beach, California, USA

Kite rigs power a variety of recreational conveyances on water and land. On water, kites are used to power surf-board-like boards in the sport of kitesurfing. Kiteboating is done in boats with kite rigs. On land, kite landboarding derives the same mode of power for skate-board-like boards. Over snow, kites power snowboards or skis in the sport of snowkiting.[ citation needed ] Traction kites for solosports generally have an area of 1-16 square meters, with anything over ~5 square meters being a big kite that requires expertise. [2]

Ships

Ship-pulling kites run to hundreds of square meters of area and require a special attachment points, a launch and recovery system, and fly-by-wire controls.

The SkySails propulsion system consists of a large foil kite, an electronic control system for the kite, and an automatic system to retract the kite.

The kite, while 1–2 orders of magnitude larger, bears similarities to the arc kites used in kitesurfing. However, the kite is an inflatable rather than a ram-air kite.[ citation needed ] Additionally, a control pod is used rather than direct tension on multiple kite control lines; only one line runs the full distance from kite to ship, with the bridle lines running from kite to control pod. Power to the pod is provided by cables embedded in the line; the same line also carries commands to the control pod from the ship. [3]

The kite is launched and recovered by an animated mast or arm, which grips the kite by its leading edge. The mast also inflates and deflates the kite. When not in use, mast and deflated kite fold away. [3]

Use

A commercial cargo ship, the MS Beluga Skysails, was built, and launched in 2007, with a kite rig supplementing conventional propulsion. [4] A European Union-funded four-year study of wind propulsion, using the MS Beluga Skysails, reported that the ship attained 5% fuel savings overall, which translated into 530 tonnes (530 t; 580 short tons) of CO2 for a typical year and itinerary. The study concluded that 25,000 similarly equipped ships could reduce fuel consumption by 5.6–8.1 megatonnes (5.6–8.1 Mt; 6,200,000–8,900,000 short tons) and save 170–25 megatonnes (170–25 Mt; 187,000,000–28,000,000 short tons) of CO2, 45–65 kilotonnes (45–65 kt; 50,000–72,000 short tons) of NOx. The return on investment for installing a kite sail was estimated to be about two-three years. [5] On her maiden voyage, MS Beluga Skysails saved an estimated 10–15% fuel, $1,000 to $1,500 per day, while the kite was in use. [6]

Maartje Theadora, a large fishing trawler, was retrofitted with a kite rig in 2010. [7]

Companies

Skysails and KiteShip both made kite rigs. [1]

See also

Related Research Articles

Ship Large watercraft

A ship is a large vessel that travels the world's oceans and other navigable waterways, carrying cargo or passengers, or in support of specialized missions, such as defense, research and fishing. Ships are generally distinguished from boats, based on size, shape, load capacity and purpose. Ships have supported exploration, trade, warfare, migration, colonization, and science. Ship transport is responsible for the largest portion of world commerce.

<span class="mw-page-title-main">Sailing</span> Propulsion of a vehicle by wind power

Sailing employs the wind—acting on sails, wingsails or kites—to propel a craft on the surface of the water, on ice (iceboat) or on land over a chosen course, which is often part of a larger plan of navigation.

<span class="mw-page-title-main">Sailing ship</span> Large wind-powered water vessel

A sailing ship is a sea-going vessel that uses sails mounted on masts to harness the power of wind and propel the vessel. There is a variety of sail plans that propel sailing ships, employing square-rigged or fore-and-aft sails. Some ships carry square sails on each mast—the brig and full-rigged ship, said to be "ship-rigged" when there are three or more masts. Others carry only fore-and-aft sails on each mast, for instance some schooners. Still others employ a combination of square and fore-and-aft sails, including the barque, barquentine, and brigantine.

<span class="mw-page-title-main">Kiteboarding</span> Extreme sport

Kiteboarding or kitesurfing is a sport that involves using wind power with a large power kite to pull a rider across a water, land, snow, sand, or other surface. It combines the aspects of paragliding, surfing, windsurfing, skateboarding, snowboarding, and wakeboarding. Kiteboarding is among the less expensive and more convenient sailing sports.

<span class="mw-page-title-main">Power kite</span> Large kite designed to provide significant pull to the user

A power kite or traction kite is a large kite designed to provide significant pull to the user.

<span class="mw-page-title-main">Foil kite</span> Type of tethered wing

Foil kites are soft kites based on the design of the parafoil. They consist of a number of cells running fore to aft, some or all of which are open at the front to allow air to inflate the kite so it takes on an aerofoil section. Due to the amount of power that these kites can generate, they can be used for a variety of different activities including kitesurfing, kite landboarding, snowkiting, kite buggying, kite-energy systems or airborne wind energy, and recreational kiting.

Kite types, kite mooring, and kite applications result in a variety of kite control systems. Contemporary manufacturers, kite athletes, kite pilots, scientists, and engineers are expanding the possibilities.

This glossary of nautical terms is an alphabetical listing of terms and expressions connected with ships, shipping, seamanship and navigation on water. Some remain current, while many date from the 17th to 19th centuries. The word nautical derives from the Latin nauticus, from Greek nautikos, from nautēs: "sailor", from naus: "ship".

<span class="mw-page-title-main">Windsport</span>

A windsport is any type of sport which involves wind-power, often involving a non-rigid airfoil such as a sail or a power kite. The activities can be land-based, on snow, on ice or on water. Windsport activity may be regulated in some countries by aviation/maritime authorities if they are likely to interfere with other activities. Local authorities may also regulate activity in certain areas, especially on crowded beaches and parks.

<span class="mw-page-title-main">Full-rigged ship</span> Sailing vessel with three or more square-rigged masts

A full-rigged ship or fully rigged ship is a sailing vessel with a sail plan of three or more masts, all of them square-rigged. Such a vessel is said to have a ship rig or be ship-rigged, with each mast stepped in three segments: lower, top, and topgallant.

<span class="mw-page-title-main">Snowkiting</span> Outdoor individual winter sport using kite power to glide on snow or ice

Snowkiting or kite skiing is an outdoor winter sport where people use kite power to glide on snow or ice. The skier uses a kite to give them power over large jumps. The sport is similar to water-based kiteboarding, but with the footwear used in snowboarding or skiing. The principles of using the kite are the same, but in different terrain. In the early days of snowkiting, foil kites were the most common type; nowadays many kiteboarders use inflatable kites. However, since 2013, newly developed racing foil kites seem to dominate speed races and expedition races, like Red Bull Ragnarok and the Vake mini-expedition race. Snowkiting differs from other alpine sports in that it is possible for the snowkiter to travel uphill and downhill with any wind direction. Like kiteboarding, snowkiting can be very hazardous and should be learned and practiced with care. Snowkiting has become more popular in places often associated with skiing and snowboarding, such as Russia, Canada, Iceland, France, Switzerland, Austria, Norway, Sweden, Finland and the Northern and Central United States. The sport has become more diverse as adventurers use kites to travel great distances and sports enthusiasts push the boundaries of freestyle, big air, speed and back country exploration.

<span class="mw-page-title-main">Kite buggy</span> Recreational vehicle powered by a kite

A kite buggy is a light, purpose-built vehicle powered by a traction kite. It is single-seated and has one steerable front wheel and two fixed rear wheels. The driver sits in the seat located in the middle of the vehicle and accelerates and slows down by applying steering manoeuvres in coordination with flying manoeuvres of the kite. This activity is called kite buggying. The speed achieved in kite buggies by skilled drivers can range up to around 110 km/h (70 mph), hence protective clothing, including a safety helmet, is commonly worn.

<span class="mw-page-title-main">Rotor ship</span> Ship with Flettner rotors as sails

A rotor ship is a type of ship designed to use the Magnus effect for propulsion. The ship is propelled, at least in part, by large powered vertical rotors, sometimes known as rotor sails. German engineer Anton Flettner was the first to build a ship that attempted to tap this force for propulsion, and ships using his type of rotor are sometimes known as Flettner ships.

<span class="mw-page-title-main">Kiteboating</span>

Kiteboating or kite boating is the act of using a kite rig as a power source to propel a boat. Kiteboating is a type of surface water sport, but it also has transportation uses

<span class="mw-page-title-main">Kite landboarding</span>

Kite landboarding, also known as land kiteboarding or flyboarding, is based on the sport of kitesurfing, where a rider on a surf-style board is pulled over water by a kite. Kite landboarding involves the use of a mountain board or landboard, which is essentially an oversized skateboard with large pneumatic wheels and foot-straps. Kite landboarding is a growing sport, and there are several competitions. Kite landboarding is attracting growing publicity although it is not yet as popular or as well known as kitesurfing.

SkySails Group GmbH is a Hamburg-based company that sells kite rigs to propel cargo ships, large yachts and fishing vessels by wind energy as well as airborne wind energy systems for electricity production from high-altitude winds.

MS Onego Deusto is a commercial container cargo ship. It is the world's first ship partially powered by a computer-controlled kite rig, called the SkySails system. It consists of a kite similar to a huge paraglider of up to 160 square metres (1,700 sq ft) area.

Different types of flying kites have niche applications. In nature, some animals, such as spiders, also make use of kiting.

Wind assisted propulsion is the practice of decreasing the fuel consumption of a merchant vessel through the use of sails or some other wind capture device. Sails used to be the primary means of propelling ships, but with the advent of the steam engine and the diesel engine, sails came to be used for recreational sailing only. In recent years with increasing fuel costs and an increased focus on reducing emissions, there has been increased interest in harnessing the power of the wind to propel commercial ships.

This glossary of nautical terms is an alphabetical listing of terms and expressions connected with ships, shipping, seamanship and navigation on water. Some remain current, while many date from the 17th to 19th centuries. The word nautical derives from the Latin nauticus, from Greek nautikos, from nautēs: "sailor", from naus: "ship".

References

  1. 1 2 Skysails, Captain John Konrad, Mariner's Weather Log, April 2009, Volume 53, No. 1, National Weather Service
  2. "Selecting your first traction kite".
  3. 1 2 Airborne Wind Energy Systems, a review of the technologies, A. cherubini, A. Papini, R. Vertechy, M.Fontana, Renewable and Sustainable Energy Reviews, 2015
  4. "Kite to pull ship across Atlantic". BBC. 2008-01-22. Retrieved 2008-01-22.
  5. Koutsoutos, Anja. "WINTECC - Demonstration of an innovative wind propulsion technology for cargo vessels". ec.europa.eu. Beluga Fleet Management GmbH. Retrieved 2017-03-30.
  6. Sanderson, Katharine (2008). "Ship kites in to port". Nature News. Nature. doi:10.1038/news.2008.564 . Retrieved 1 January 2016.
  7. "Fishing trawler will be powered by a 160m2 kite propulsion system". SurferToday. January 5, 2010. Retrieved 27 June 2010.