An airplane (American English), or aeroplane (Commonwealth English), informally plane, is a fixed-wing aircraft that is propelled forward by thrust from a jet engine, propeller, or rocket engine. Airplanes come in a variety of sizes, shapes, and wing configurations. The broad spectrum of uses for airplanes includes recreation, transportation of goods and people, military, and research. Worldwide, commercial aviation transports more than four billion passengers annually on and transports more than 200 billion tonne-Measured in RTKs—an RTK is one tonne of revenue freight carried one kilometer. of cargo annually, which is less than 1% of the world's cargo movement. Most airplanes are flown by a pilot on board the aircraft, but some are designed to be remotely or computer-controlled such as drones.
The Wright brothers invented and flew the Wright Flyer in 1903, recognized as "the first sustained and controlled heavier-than-air powered flight". FAI News: 100 Years Ago, the Dream of Icarus Became Reality posted 17 December 2003. Retrieved: 5 January 2007. They built on the works of George Cayley dating from 1799, when he set forth the concept of the modern airplane (and later built and flew models and successful passenger-carrying Glider aircraft)
target="_blank" rel="nofollow"> "Cayley, Sir George: Encyclopædia Britannica 2007". Encyclopædia Britannica Online, 25 August 2007. and the work of German pioneer of human aviation Otto Lilienthal, who, between 1867 and 1896, also studied heavier-than-air flight. Lilienthal's flight attempts in 1891 are seen as the beginning of human flight.
Following its limited use in World War I, aircraft technology continued to develop. Airplanes had a presence in all the major battles of World War II. The first jet aircraft was the German Heinkel He 178 in 1939. The first jet airliner, the de Havilland Comet, was introduced in 1952. The Boeing 707, the first widely successful commercial jet, was in commercial service for more than 60 years, from 1958 to 2019.
In the United States and Canada, the term "airplane" is used for powered fixed-wing aircraft. In the United Kingdom and Ireland and most of the Commonwealth, the term "aeroplane" () is usually applied to these aircraft.
Some of the earliest recorded attempts with Glider aircraft were those by the 9th-century Andalusian and Arabic-language poet Abbas ibn Firnas and the 11th-century English monk Eilmer of Malmesbury; both experiments injured their pilots.White, Lynn. "Eilmer of Malmesbury, an Eleventh Century Aviator: A Case Study of Technological Innovation, Its Context and Tradition". Technology and Culture, Volume 2, Issue 2, 1961, pp. 97–111 (97–99 resp. 100–101). Leonardo da Vinci researched the wing design of birds and designed a man-powered aircraft in his Codex on the Flight of Birds (1502), noting for the first time the distinction between the center of mass and the center of pressure of flying birds.
In 1799, George Cayley set forth the concept of the modern airplane as a fixed-wing flying machine with separate systems for lift, propulsion, and control. Cayley was building and flying models of fixed-wing aircraft as early as 1803, and he built a successful passenger-carrying Glider aircraft in 1853. In 1856, Frenchman Jean-Marie Le Bris made the first powered flight, by having his glider "L'Albatros artificiel" pulled by a horse on a beach. Then the Russian Alexander F. Mozhaisky also made some innovative designs. In 1883, the American John J. Montgomery made a controlled flight in a glider.The Journal of San Diego History, July 1968, Vol. 14, No. 3 Other aviators who made similar flights at that time were Otto Lilienthal, Percy Pilcher, and Octave Chanute.
Sir Hiram Maxim built a craft that weighed 3.5 tons, with a wingspan that was powered by two steam engines driving two propellers. In 1894, his machine was tested with overhead rails to prevent it from rising. The test showed that it had enough lift to take off. The craft was uncontrollable and it is presumed that Maxim realized this because he subsequently abandoned work on it.Beril, Becker (1967). Dreams and Realities of the Conquest of the Skies. New York: Atheneum. pp. 124–125
Between 1867 and 1896, the German pioneer of human aviation Otto Lilienthal developed heavier-than-air flight. He was the first person to make well-documented, repeated, successful gliding flights. Lilienthal's work led to him developing the concept of the modern wing, his flight attempts in 1891 are seen as the beginning of human flight, the "Lilienthal Normalsegelapparat" is considered to be the first airplane in series production and his work heavily inspired the Wright brothers.Crouch 1989, pp. 226–228.
In the 1890s, Lawrence Hargrave conducted research on wing structures and developed a box kite that lifted the weight of a man. His box kite designs were widely adopted. Although he also developed a type of rotary aircraft engine, he did not create and fly a powered fixed-wing aircraft.
The American Wright brothers's flights in 1903 are recognized by the Fédération Aéronautique Internationale (FAI), the standard-setting and record-keeping body for aeronautics, as "the first sustained and controlled heavier-than-air powered flight". By 1905, the Wright Flyer III was capable of fully controllable, stable flight for substantial periods. The Wright brothers credited Otto Lilienthal as a major inspiration for their decision to pursue manned flight.
In 1906, the Brazilian Alberto Santos-Dumont made what was claimed to be the first airplane flight unassisted by catapult and set the first world record recognized by the Aéro-Club de France by flying in less than 22 seconds.Jones, Ernest. "Santos Dumont in France 1906–1916: The Very Earliest Early Birds". earlyaviators.com, 25 December 2006. Retrieved: 17 August 2009. This flight was also certified by the FAI. Les vols du 14bis relatés au fil des éditions du journal l'illustration de 1906. The wording is: "cette prouesse est le premier vol au monde homologué par l'Aéro-Club de France et la toute jeune Fédération Aéronautique Internationale (FAI)." Santos-Dumont: Pionnier de l'aviation, dandy de la Belle Epoque.
An early aircraft design that brought together the modern monoplane tractor configuration was the Blériot VIII design of 1908. It had movable tail surfaces controlling both yaw and pitch, a form of roll control supplied either by wing warping or by ailerons and controlled by its pilot with a joystick and rudder bar. It was an important predecessor of his later Blériot XI English Channel-crossing aircraft of the summer of 1909.
World War I served as a testbed for the use of the airplane as a weapon. Airplanes demonstrated their potential as mobile observation platforms, then proved themselves to be machines of war capable of causing casualties to the enemy. The earliest known aerial victory with a synchronized machine gun-armed fighter aircraft occurred in 1915, by German Luftstreitkräfte Leutnant Kurt Wintgens. Flying ace appeared; the greatest (by number of Aerial Combat victories) was Manfred von Richthofen, also known as the Red Baron.
Following WWI, aircraft technology continued to develop. Alcock and Brown crossed the Atlantic non-stop for the first time in 1919. The first international commercial flights took place between the United States and Canada in 1919.
Airplanes had a presence in all the major battles of World War II. They were an essential component of the military strategies of the period, such as the German Blitzkrieg, The Battle of Britain, and the American and Japanese aircraft carrier campaigns of the Pacific War.
The first jet airliner, the de Havilland Comet, was introduced in 1952. The Boeing 707, the first widely successful commercial jet, was in commercial service for more than 50 years, from 1958 to 2010. The Boeing 747 was the world's biggest passenger aircraft from 1970 until it was surpassed by the Airbus A380 in 2005.
Supersonic airliner flights, including those of the Concorde, have been limited to over-water flight at supersonic speed because of their sonic boom, which is prohibited over most populated land areas. The high cost of operation per passenger-mile and a deadly crash in 2000 induced the operators of the Concorde to remove it from service.
Subsonic aircraft, such as airliners, employ high by-pass jet engines for fuel efficiency. Supersonic aircraft, such as jet fighters, use low-bypass turbofans. However at supersonic speeds, the air entering the engine must be decelerated to a subsonic speed and then re-accelerated back to supersonic speeds after combustion. An afterburner may be used on combat aircraft to increase power for short periods of time by injecting fuel directly into the hot exhaust gases. Many jet aircraft also use to slow down after landing.
In World War II, the Germans deployed the Me 163 Komet rocket-powered aircraft. The first plane to break the sound barrier in level flight was a rocket plane – the Bell X-1 in 1948. The North American X-15 broke many speed and altitude records in the 1960s and pioneered engineering concepts for later aircraft and spacecraft. Military transport aircraft may employ rocket-assisted take offs for short-field situations. Otherwise, rocket aircraft include , like SpaceShipTwo, for travel beyond the Earth's atmosphere and sport aircraft developed for the short-lived Rocket Racing League.
During this process, the objectives and design specifications of the aircraft are established. First the construction company uses drawings and equations, simulations, wind tunnel tests and experience to predict the behavior of the aircraft. Computers are used by companies to draw, plan and do initial simulations of the aircraft. Small models and mockups of all or certain parts of the plane are then tested in wind tunnels to verify its aerodynamics.
When the design has passed through these processes, the company constructs a limited number of prototypes for testing on the ground. Representatives from an aviation governing agency often make a first flight. The flight tests continue until the aircraft has fulfilled all the requirements. Then, the governing public agency of aviation of the country authorizes the company to begin production.
In the United States, this agency is the Federal Aviation Administration (FAA). In the European Union, European Aviation Safety Agency (EASA); in the United Kingdom it is the Civil Aviation Authority (CAA). In Canada, the public agency in charge and authorizing the mass production of aircraft is Transport Canada Civil Aviation Authority.
When a part or component needs to be joined together by welding for virtually any aerospace or defense application, it must meet the most stringent and specific safety regulations and standards. Nadcap, or the National Aerospace and Defense Contractors Accreditation Program sets global requirements for quality, quality management and quality assurance for aerospace engineering.
In the case of international sales, a license from the public agency of aviation or transport of the country where the aircraft is to be used is also necessary. For example, airplanes made by the European company, Airbus, need to be certified by the FAA to be flown in the United States, and airplanes made by U.S.-based Boeing need to be approved by the EASA to be flown in the European Union.
Regulations have resulted in reduced Aircraft noise from aircraft engines in response to increased noise pollution from growth in air traffic over urban areas near airports.
Small planes can be designed and constructed by amateurs as homebuilts. Other homebuilt aircraft can be assembled using pre-manufactured kits of parts that can be assembled into a basic plane and must then be completed by the builder.Purdy, Don: AeroCrafter - Homebuilt Aircraft Sourcebook, Fifth Edition, pages 1–164. BAI Communications, 15 July 1998.
Few companies produce planes on a large scale. However, the production of a plane for one company is a process that actually involves dozens, or even hundreds, of other companies and plants, that produce the parts that go into the plane. For example, one company can be responsible for the production of the landing gear, while another one is responsible for the radar. The production of such parts is not limited to the same city or country; in the case of large plane manufacturing companies, such parts can come from all over the world. The parts are sent to the main plant of the plane company, where the production line is located. In the case of large planes, production lines dedicated to the assembly of certain parts of the plane can exist, especially the wings and the fuselage.
Typical structural parts include:
Whether flexible or rigid, most wings have a strong frame to give them their shape and to transfer lift from the wing surface to the rest of the aircraft. The main structural elements are one or more spars running from root to tip, and many ribs running from the leading (front) to the trailing (rear) edge.
Early airplane engines had little power, and lightness was very important. Also, early airfoil sections were very thin, and could not have a strong frame installed within. So, until the 1930s, most wings were too lightweight to have enough strength, and external bracing struts and wires were added. When the available engine power increased during the 1920s and 30s, wings could be made heavy and strong enough that bracing was not needed any more. This type of unbraced wing is called a cantilever wing.
A monoplane has a single wing plane, a biplane has two stacked one above the other, a tandem wing has two placed one behind the other. When the available engine power increased during the 1920s and 30s and bracing was no longer needed, the unbraced or cantilever monoplane became the most common form of powered type.
The wing planform is the shape when seen from above. To be aerodynamically efficient, a wing should be straight with a long span from side to side but have a short chord (high aspect ratio). But to be structurally efficient, and hence light weight, a wing must have a short span but still enough area to provide lift (low aspect ratio).
At transonic speeds (near the speed of sound), it helps to sweep the wing backwards or forwards to reduce drag from supersonic shock waves as they begin to form. The swept wing is just a straight wing swept backwards or forwards.
The delta wing is a triangle shape that may be used for several reasons. As a flexible Rogallo wing, it allows a stable shape under aerodynamic forces and so is often used for ultralight aircraft and even kites. As a supersonic wing, it combines high strength with low drag and so is often used for fast jets.
A variable geometry wing can be changed in flight to a different shape. The variable-sweep wing transforms between an efficient straight configuration for takeoff and landing, to a low-drag swept configuration for high-speed flight. Other forms of variable planform have been flown, but none have gone beyond the research stage.
The flying wing configuration was studied extensively in the 1930s and 1940s, notably by Jack Northrop and Cheston L. Eshelman in the United States, and Alexander Lippisch and the Horten brothers in Germany. After the war, several experimental designs were based on the flying wing concept, but the known difficulties remained intractable. Some general interest continued until the early 1950s but designs did not necessarily offer a great advantage in range and presented several technical problems, leading to the adoption of "conventional" solutions like the Convair B-36 and the B-52 Stratofortress. Due to the practical need for a deep wing, the flying wing concept is most practical for designs in the slow-to-medium speed range, and there has been continual interest in using it as a tactical design.
Interest in flying wings was renewed in the 1980s due to their potentially low radar reflection cross-sections. Stealth technology relies on shapes which only reflect radar waves in certain directions, thus making the aircraft hard to detect unless the radar receiver is at a specific position relative to the aircraft - a position that changes continuously as the aircraft moves. This approach eventually led to the Northrop B-2 Spirit Stealth aircraft bomber. In this case, the aerodynamic advantages of the flying wing are not the primary needs. However, modern computer-controlled fly-by-wire systems allowed for many of the aerodynamic drawbacks of the flying wing to be minimized, making for an efficient and stable long-range bomber.
Thus blended wing bodied aircraft incorporate design features from both a futuristic fuselage and flying wing design. The purported advantages of the blended wing body approach are efficient high-lift wings and a wide airfoil-shaped body. This enables the entire craft to contribute to lift generation with the result of potentially increased fuel economy.
Lifting bodies were a major area of research in the 1960s and 70s as a means to build a small and lightweight crewed spacecraft. The US built several famous lifting body rocket planes to test the concept, as well as several rocket-launched re-entry vehicles that were tested over the Pacific. Interest waned as the US Air Force lost interest in the crewed mission, and major development ended during the Space Shuttle design process when it became clear that the highly shaped fuselages made it difficult to fit fuel tankage.
To achieve stability and control, most fixed-wing types have an empennage comprising a fin and rudder which act horizontally and a tailplane and elevator which act vertically. These control surfaces can typically be trimmed to relieve control forces for various stages of flight. This is so common that it is known as the conventional layout. Sometimes there may be two or more fins, spaced out along the tailplane.
Some types have a horizontal "canard" foreplane ahead of the main wing, instead of behind it.Crane, Dale: Dictionary of Aeronautical Terms, third edition, page 86. Aviation Supplies & Academics, 1997. Aviation Publishers Co. Limited, From the Ground Up, page 10 (27th revised edition) This foreplane may contribute to the lift, the trim, or control of the aircraft, or to several of these.
On manned aircraft, cockpit instruments provide information to the pilots, including flight data, Aircraft engine, navigation, communications and other aircraft systems that may be installed.
Another environmental impact of airplanes is noise pollution, mainly caused by aircraft taking off and landing.
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