A helicopter is a type of rotorcraft A rotorcraft or rotary wing aircraft is a heavier-than-air flying machine that uses lift generated by wings, called rotor blades, that revolve around a mast. Several rotor blades mounted to a single mast are referred to as a rotor. The International Civil Aviation Organization defines a rotorcraft as "supported in flight by the reactions of in which lift A fluid flowing past the surface of a body exerts a surface force on it. Lift is defined to be the component of this force that is perpendicular to the oncoming flow direction. It contrasts with the drag force, which is defined to be the component of the surface force parallel to the flow direction and thrust Thrust is a reaction force described quantitatively by Newton's second and third laws. When a system expels or accelerates mass in one direction the accelerated mass will cause a proportional but opposite force on that system are supplied by one or more engine driven rotors A helicopter main rotor or rotor system is a type of fan that is used to generate both the aerodynamic lift force that supports the weight of the helicopter, and thrust which counteracts aerodynamic drag in forward flight. Each main rotor is mounted on a vertical mast over the top of the helicopter, as opposed to a helicopter tail rotor, which is. In contrast with fixed-wing aircraft A fixed-wing aircraft, typically called an airplane, aeroplane or plane, is an aircraft capable of flight using forward motion that generates lift as the wing moves through the air. Planes include jet engine and propeller driven vehicles propelled forward by thrust, as well as unpowered aircraft . Fixed-wing aircraft are distinct from ornithopters, this allows the helicopter to take off and land vertically, to hover, and to fly forwards, backwards and laterally. These attributes allow helicopters to be used in congested or isolated areas where fixed-wing aircraft would not be able to take off or land. The capability to efficiently hover for extended periods of time allows a helicopter to accomplish tasks that fixed-wing aircraft and other forms of vertical takeoff and landing VTOL is an abbreviation for Vertical Take-Off and Landing aircraft. See also V/STOL. This classification includes fixed-wing aircraft that can hover, take off and land vertically as well as helicopters and other aircraft with powered rotors, such as tiltrotors. Autogyros, balloons, airships and rockets are not normally considered VTOL, but may be aircraft cannot perform.
The word 'helicopter' is adapted from the French hélicoptère, coined by Gustave de Ponton d'Amecourt in 1861, which originates from the Greek helix/helik- (ἕλικ-) = 'spiral' or 'turning' and pteron (πτερόν) = 'wing'.[1][2]
Helicopters were developed and built during the first half-century of flight Flight is the process by which an object moves either through the air, or movement beyond earth's atmosphere , by generating lift, propulsive thrust or aerostatically using buoyancy, or by simple ballistic movement, with some reaching limited production, but it was not until 1942 that a helicopter designed by Igor Sikorsky Igor Sikorsky , born Igor Ivanovich Sikorsky (Russian: Игорь Иванович Сикорский, Ukrainian: Ігор Іванович Сікорський), was a Russian-American pioneer of aviation in both helicopters and fixed-wing aircraft. He designed and flew the world's first multi-engine fixed-wing aircraft, the Russky Vityaz in 1913 reached full-scale production Mass production is the production of large amounts of standardized products, including and especially on assembly lines. The concepts of mass production are applied to various kinds of products, from fluids and particulates handled in bulk (such as food, fuel, chemicals, and mined minerals) to discrete solid parts (such as fasteners) to assemblies,[3] with 131 aircraft built.[4] Though most earlier designs used more than one main rotor, it was the single main rotor with antitorque tail rotor The tail rotor, or anti-torque rotor, is a smaller rotor mounted so that it rotates vertically or near-vertically at the end of the tail of a traditional single-rotor helicopter. The tail rotor's position and distance from the center of gravity allow it to develop thrust in the same direction as the main rotor's rotation, to counter the torque configuration of this design that would come to be recognized worldwide as the helicopter.
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History
The earliest references for vertical flight have come from China. Since around 400 BC,[5] Chinese China is seen variously as an ancient civilization extending over a large area in East Asia, a nation and/or a multinational entity children have played with bamboo flying toys Bamboo-copter is a Chinese children's toy invented around 400 BC . It essentially consists of a propeller on a stick, and rolling the stick in the right direction spins the propeller, causing the toy to "take off" when it is let go of. This toy made its way to Europe and is depicted in a 1463 European painting. "Bao Pu Zi" (抱,[6][7] and the 4th-century AD Daoist Taoism refers to a variety of related philosophical and religious traditions that have influenced Eastern Asia for more than two millennia, and have had a notable influence on the western world particularly since the 19th century. The word 道, Tao (or Dao, depending on the romanization scheme), roughly translates as, "path" or "way& book Baopuzi The Baopuzi , written by the Jin Dynasty scholar Ge Hong 葛洪 (283-343), is divided into esoteric Neipian 內篇 "Inner Chapters" and exoteric Waipian 外篇 "Outer Chapters". The Daoist Inner Chapters discuss topics such as techniques for xian 仙 "immortality; transcendence", Chinese alchemy, elixirs, and (抱朴子 "Master who Embraces Simplicity") reportedly describes some of the ideas inherent to rotary wing aircraft:[8]
| “ | Someone asked the master about the principles of mounting to dangerous heights and traveling into the vast inane. The Master said, "Some have made flying cars with wood from the inner part of the jujube Ziziphus zizyphus , commonly called jujube, red date, or chinese date, is a species of Ziziphus in the buckthorn family Rhamnaceae, used primarily for its fruits. Common names in Arabic are nabq, dum, tsal, sadr and sidr, the last of which also means Ziziphus lotus. In Persian it is called anab or annab , a name also used in lebanon tree, using ox-leather [straps] fastened to returning blades so as to set the machine in motion."[9] | ” |
It was not until the early 1480s, when Leonardo da Vinci Leonardo di ser Piero da Vinci ( pronunciation ), (April 15, 1452 – May 2, 1519), was an Italian polymath: painter, sculptor, architect, musician, scientist, mathematician, engineer, inventor, anatomist, geologist, cartographer, botanist and writer. Leonardo has often been described as the archetype of the Renaissance man, a man whose created a design for a machine that could be described as an "aerial screw", that any recorded advancement was made towards vertical flight. His notes suggested that he built small flying models, but there were no indications for any provision to stop the rotor from making the whole craft rotate.[10][11] As scientific knowledge increased and became more accepted, men continued to pursue the idea of vertical flight. Many of these later models and machines would more closely resemble the ancient bamboo flying top with spinning wings, rather than Da Vinci's screw.
Prototype created by M. Lomonosov Mikhail Vasilyevich Lomonosov (Russian: Михаи́л Васи́льевич Ломоно́сов; November 19 [O.S. November 8] 1711– April 15 [O.S. April 4] 1765) was a Russian polymath, scientist and writer, who made important contributions to literature, education, and science. Among his discoveries was the atmosphere of Venus. His spheres, 1754In July 1754, Mikhail Lomonosov Mikhail Vasilyevich Lomonosov (Russian: Михаи́л Васи́льевич Ломоно́сов; November 19 [O.S. November 8] 1711– April 15 [O.S. April 4] 1765) was a Russian polymath, scientist and writer, who made important contributions to literature, education, and science. Among his discoveries was the atmosphere of Venus. His spheres demonstrated a small coaxial rotor to the Russian Academy of Sciences The Russian Academy of Sciences consists of the national academy of Russia and a network of scientific research institutes from across the Russian Federation as well as auxiliary scientific and social units like libraries, publishers and hospitals. It was powered by a spring and suggested as a method to lift meteorological Meteorology is the interdisciplinary scientific study of the atmosphere that focuses on weather processes and short term forecasting . Studies in the field stretch back millennia, though significant progress in meteorology did not occur until the eighteenth century. The nineteenth century saw breakthroughs occur after observing networks developed instruments. In 1783, Christian de Launoy, and his mechanic Many mechanics are specialized in a particular field such as auto mechanics, bicycle mechanics, motorcycle mechanics, boiler mechanics, general mechanics, industrial maintenance mechanics , air conditioning and refrigeration mechanics, aircraft mechanics, diesel mechanics, and tank mechanics in the armed services. Auto mechanics, for example, have, Bienvenu, made a model with a pair of counter-rotating rotors, using turkey A turkey is either of two or three living species of large birds in the genus Meleagris. One species, Meleagris gallopavo, commonly known as the Wild Turkey, is native to the forests of North America. The other species, Meleagris ocellata, known as the Ocellated Turkey, is native to the forests of the Yucatán Peninsula flight feathers as rotor blades, and in 1784, demonstrated it to the French Academy of Sciences The French Academy of Sciences is a learned society, founded in 1666 by Louis XIV at the suggestion of Jean-Baptiste Colbert, to encourage and protect the spirit of French scientific research. It was at the forefront of scientific developments in Europe in the 17th and 18th centuries. It is one of the earliest academies of sciences. Sir George Cayley Sir George Cayley, 6th Baronet , sometimes known as "the father of Aerodynamics", was a prolific English engineer from Brompton-by-Sawdon, near Scarborough in Yorkshire. He was a pioneer of aeronautical engineering, though he worked over half a century before the development of powered flight. He served for the Whig party as Member of, influenced by a childhood fascination with the Chinese flying top, grew up to develop a model of feathers, similar to Launoy and Bienvenu, but powered by rubber bands. By the end of the century, he had progressed to using sheets of tin for rotor blades and springs for power. His writings on his experiments and models would become influential on future aviation pioneers.[10] Alphonse Pénaud Alphonse Pénaud , was a 19th-century French pioneer of aviation, inventor of the rubber powered model airplane Planophore and founder of the aviation industry would later develop coaxial rotor model helicopter toys in 1870, also powered by rubber bands. One of these toys, given as a gift by their father, would inspire the Wright brothers The Wright brothers, Orville and Wilbur (April 16, 1867 – May 30, 1912), were two Americans who are generally credited with inventing and building the world's first successful airplane and making the first controlled, powered and sustained heavier-than-air human flight, on December 17, 1903. In the two years afterward, the brothers developed to pursue the dream of flight.[12]
In 1861, the word "helicopter" was coined by Gustave de Ponton d'Amécourt, a French inventor who demonstrated a small, steam-powered model. While celebrated as an innovative use of a new metal, aluminum, the model never lifted off the ground. D'Amecourt's linguistic contribution would survive to eventually describe the vertical flight he had envisioned. Steam power was popular with other inventors as well. In 1878 Enrico Forlanini Enrico Forlanini was an Italian engineer, inventor and aeronautical pioneer, well known for his works on helicopters, aircraft, hydrofoils and dirigibles. He was born in Milan. His older brother Carlo Forlanini was a famous Italian physician (1847-1918)'s unmanned helicopter was also powered by a steam engine. It was the first of its type that rose to a height of 12 meters (40 ft), where it hovered for some 20 seconds after a vertical take-off. Emmanuel Dieuaide's steam-powered design featured counter-rotating rotors powered through a hose from a boiler on the ground.[10]
In 1885, Thomas Edison Thomas Alva Edison was an American inventor, scientist, and businessman who developed many devices that greatly influenced life around the world, including the phonograph, the motion picture camera, and a long-lasting, practical electric light bulb. Dubbed "The Wizard of Menlo Park" (now Edison, New Jersey) by a newspaper reporter, he was given US$1,000 by James Gordon Bennett, Jr., to conduct experiments towards developing flight. Edison built a helicopter and used the paper for a stock ticker to create guncotton Nitrocellulose is a highly flammable compound formed by nitrating cellulose through exposure to nitric acid or another powerful nitrating agent. When used as a propellant or low-order explosive, it is also known as guncotton, with which he attempted to power an internal combustion engine. The helicopter was damaged by explosions and one of his workers was badly burned. Edison reported that it would take a motor with a ratio of three to four pounds per horsepower produced to be successful, based on his experiments.[13] Ján Bahýľ, a Slovak The Slovaks are a western Slavic people that primarily inhabit Slovakia and speak the Slovak language, which is closely related to the Czech language inventor, adapted the internal combustion engine The internal combustion engine is an engine in which the combustion of a fuel occurs with an oxidizer (usually air) in a combustion chamber. In an internal combustion engine the expansion of the high temperature and pressure gases, which are produced by the combustion, directly applies force to a movable component of the engine, such as the to power his helicopter model that reached a height of 0.5 meters (1.6 ft) in 1901. On 5 May 1905, his helicopter reached four meters (13 ft) in altitude and flew for over 1,500 meters (4,900 ft).[14] In 1908, Edison patented his own design for a helicopter powered by a gasoline engine with box kites attached to a mast by cables for a rotor, but it never flew.[15]
First flights
Paul Cornu's helicopter in 1907In 1906, two French brothers, Jacques and Louis Breguet, began experimenting with airfoils for helicopters and in 1907, those experiments resulted in the Gyroplane No.1. Although there is some uncertainty about the dates, sometime between 14 August and 29 September 1907, the Gyroplane No. 1 lifted its pilot up into the air about two feet (0.6 m) for a minute.[3] However, the Gyroplane No. 1 proved to be extremely unsteady and required a man at each corner of the airframe to hold it steady. For this reason, the flights of the Gyroplane No. 1 are considered to be the first manned flight of a helicopter, but not a free or untethered flight.
That same year, fellow French inventor Paul Cornu designed and built a Cornu helicopter that used two 20-foot (6 m) counter-rotating rotors driven by a 24-hp (18-kW) Antoinette engine. On 13 November 1907, it lifted its inventor to 1 foot (0.3 m) and remained aloft for 20 seconds. Even though this flight did not surpass the flight of the Gyroplane No. 1, it was reported to be the first truly free flight with a pilot.[n 1] Cornu's helicopter would complete a few more flights and achieve a height of nearly 6.5 feet (2 m), but it proved to be unstable and was abandoned.[3]
The Danish inventor Jacob Ellehammer built the Ellehammer helicopter in 1912. It consisted of a frame equipped with two contra-rotating discs, each of which was fitted with six vanes around its circumference. After a number of indoor tests, the aircraft was demonstrated outdoors and made a number of free take-offs. Experiments with the helicopter continued until September 1916, when it tipped over during take-off, destroying its rotors.[16]
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ambulance die in Ark. crash while attempting rescue Boston Globe An investigator looked over wreckage of the crashed helicopter ambulance in Scotland, Ark., about 80 miles north of Little Rock. ... 3 die in medical helicopter crash in Arkansas The Associated Press 3 dead in medical helicopter crash cnn medical Helicopter Crashes Up in 2010 KSBI 52 FairWarning (blog) - Xinhua - NewsOK.com
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