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Wind-powered Vehicle
Wind-powered vehicles derive their power from sails, kites or wind turbine, rotors and ride on wheels—which may be linked to a wind-powered rotor—or runners. Whether powered by sail, kite or rotor, these vehicles share a common trait: As the vehicle increases in speed, the advancing airfoil encounters an increasing apparent wind at an angle of attack that is increasingly smaller. At the same time, such vehicles are subject to relatively low forward resistance, compared with traditional sailing craft. As a result, such vehicles are often capable of speeds exceeding that of the wind. Rotor-powered examples have demonstrated ground speeds that exceed that of the wind, both directly ''into the wind'' and directly ''downwind'' by transferring power through a drive train between the rotor and the wheels. The wind-powered speed record is by a vehicle with a sail on it, ''Greenbird'', with a recorded top speed of . Other wind-powered conveyances include sailing vessels that travel on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airfield
An aerodrome, airfield, or airstrip is a location from which aircraft flight operations take place, regardless of whether they involve air cargo, passengers, or neither, and regardless of whether it is for public or private use. Aerodromes include small general aviation airfields, large commercial airports, and military air bases. The term ''airport'' may imply a certain stature (having satisfied certain certification criteria or regulatory requirements) that not all aerodromes may have achieved. That means that all airports are aerodromes, but not all aerodromes are airports. Usage of the term "aerodrome" (or "airfield") remains more common in Commonwealth English, and is conversely almost unknown in American English, where the term "airport" is applied almost exclusively. A water aerodrome is an area of open water used regularly by seaplanes, floatplanes or amphibious aircraft for landing and taking off. In formal terminology, as defined by the International Civil ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Power Kite
A power kite or traction kite is a large kite designed to provide significant pull to the user. Types The two most common forms are the foil, and the leading edge inflatable. There are also other less common types of power kite including rigid-framed kites and soft single skin kites. There are several different control systems used with these kites which have two to five lines and a bar or handles. Foil kites consist of a number of cells with cloth ribs in each cell. It is the profile of these ribs that gives the kite its aerofoil shape and enable it to generate lift. The most common type is the ram-air foil, where each cell has a gauze-covered opening at the front, meaning air is forced in during flight, giving the kite its stiffness and enabling it to hold its profile. Some ram-air foils are closed-cell, where a one-way valve locks the air inside the cells, giving some increased water relaunch capability. Leading edge inflatable kites (LEIs) are made of a single skin of f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vehicle
A vehicle () is a machine designed for self-propulsion, usually to transport people, cargo, or both. The term "vehicle" typically refers to land vehicles such as human-powered land vehicle, human-powered vehicles (e.g. bicycles, tricycles, velomobiles), animal-powered transports (e.g. horse-drawn vehicle, horse-drawn carriages/wagons, ox carts, dog sleds), motor vehicles (e.g. motorcycles, cars, trucks, buses, mobility scooters) and rail transport, railed vehicles (trains, trams and monorails), but more broadly also includes cable transport (aerial lift, cable cars and elevators), watercraft (ships, boats and underwater vehicles), amphibious vehicles (e.g. screw-propelled vehicles, hovercraft, seaplanes), aircraft (airplanes, helicopters, glider (aircraft), gliders and aerostats) and space vehicles (spacecraft, spaceplanes and launch vehicles). This article primarily concerns the more ubiquitous land vehicles, which can be broadly classified by the type of contact interface with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kite Buggy
A kite buggy is a light, purpose-built vehicle powered by a Power kite, traction kite (power 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. The kite buggy was promulgated by George Pocock (inventor) in the UK in 1827 and kite buggies were available commercially in US and UK in the late 1970s. Peter Lynn is generally attributed with the modern popularization of buggies and kite buggying with his introduction of strong, lightweight, affordable buggies in the early 1990s. Kite buggying is similar to land yachting, windsurfing or even yachting, and there ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tether
A tether is a cord, fixture, or flexible attachment that characteristically anchors something movable to something fixed; it also may be used to connect two movable objects, such as an item being towed by its tow. Applications for tethers include: fall arrest systems, lanyards, balloons, kites, airborne wind-power systems, anchors, floating water power systems, towing, animal constraint, space walks, power kiteing, and anti-theft devices. Failure Failure modes for tethers are considered in their design. A cord or rope tether may reach its breaking strength and fail. Outcomes can include an injury or fatal fall, and damage or loss of life to personnel or bystanders caused by backlash of the ruptured segments. Failure-prevention may be designed into a tethering system. Some safety harnesses are used in combination with a shock-absorbing lanyard, which has break-away stitching designed into it to prevent material failure and regulate deceleration, thereby preventing a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rope
A rope is a group of yarns, Plying, plies, fibres, or strands that are plying, twisted or braided together into a larger and stronger form. Ropes have high tensile strength and can be used for dragging and lifting. Rope is thicker and stronger than similarly constructed cord, String (structure), string, and twine. Construction Rope may be constructed of any long, stringy, fibrous material (e.g., rattan, a natural material), but generally is constructed of certain natural fibre, natural or synthetic fibre, synthetic fibres. Synthetic fibre ropes are significantly stronger than their natural fibre counterparts, they have a higher tensile strength, they are more resistant to rotting than ropes created from natural fibres, and they can be made to float on water. But synthetic ropes also possess certain disadvantages, including slipperiness, and some can be damaged more easily by UV light. Common natural fibres for rope are Manila hemp, hemp, linen, cotton, coir, jute, straw, an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Foil
An airfoil (American English) or aerofoil (British English) is a streamlined body that is capable of generating significantly more lift than drag. Wings, sails and propeller blades are examples of airfoils. Foils of similar function designed with water as the working fluid are called hydrofoils. When oriented at a suitable angle, a solid body moving through a fluid deflects the oncoming fluid (for fixed-wing aircraft, a downward force), resulting in a force on the airfoil in the direction opposite to the deflection. This force is known as aerodynamic force and can be resolved into two components: lift (perpendicular to the remote freestream velocity) and drag (parallel to the freestream velocity). The lift on an airfoil is primarily the result of its angle of attack. Most foil shapes require a positive angle of attack to generate lift, but cambered airfoils can generate lift at zero angle of attack. Airfoils can be designed for use at different speeds by modifying their geom ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kite
A kite is a tethered heavier than air flight, heavier-than-air craft with wing surfaces that react against the air to create Lift (force), lift and Drag (physics), drag forces. A kite consists of wings, tethers and anchors. Kites often have a bridle and tail to guide the face of the kite so the wind can lift it. Some kite designs do not need a bridle; box kites can have a single attachment point. A kite may have fixed or moving anchors that can balance the kite. The name is derived from the kite (bird), kite, the hovering bird of prey. There are several shapes of kites. The Lift (force), lift that sustains the kite in flight is generated when air moves around the kite's surface, producing low pressure above and high pressure below the wings. The interaction with the wind also generates horizontal Drag (physics), drag along the direction of the wind. The resultant force vector from the lift and drag force components is opposed by the tension of one or more of the rope, lines ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
International DN
The International DN is a class of iceboat. History The name stands for Detroit News, where the first iceboat of this type was designed and built in the winter of 1936–1937. Archie Arrol was a master craftsman working in the Detroit News hobby shop, and together with iceboaters Joe Lodge and Norman Jarrait designed a racing boat they called the "Blue Streak 60", later to become known as the "DN 60". In 1937 a group of 50 laymen worked with Archie in the hobby shop to produce the first fleet of the new iceboats. These first boats broke during the initial season, and after Jarrait and Lodge modified the design to increase the strength, the group got back together to build a second set of iceboats in 1938. This design, featuring a narrow, single-person cockpit, three steel blades in tricycle A tricycle, sometimes abbreviated to trike, is a Human-powered transport, human-powered (or gasoline or electric motor powered or assisted, or gravity powered) Three-wheeler, three-w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wind Speed
In meteorology, wind speed, or wind flow speed, is a fundamental atmospheric quantity caused by air moving from high to low pressure, usually due to changes in temperature. Wind speed is now commonly measured with an anemometer. Wind speed affects weather forecasting, aviation and maritime operations, construction projects, growth and metabolism rates of many plant species, and has countless other implications. Wind direction is usually almost parallel to isobars (and not perpendicular, as one might expect), due to Earth's rotation. Units The meter per second (m/s) is the SI unit for velocity and the unit recommended by the World Meteorological Organization for reporting wind speeds, and used amongst others in weather forecasts in the Nordic countries. Since 2010 the International Civil Aviation Organization (ICAO) also recommends meters per second for reporting wind speed when approaching runways, replacing their former recommendation of using kilometers per hour ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
