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Method of transport in which aircraft carry people and goods through the air. People first took to the air in balloons in 1783 and began powered flight in 1852 in airships, but the history of flying, both for civilian and military use, is dominated by the aeroplane.

The earliest planes were designed for gliding; the advent of the petrol engine saw the first powered flight by the Wright brothers in 1903 at Kitty Hawk, USA. This inspired the development of aircraft throughout Europe. Biplanes were succeeded by monoplanes in the 1930s. The first jet plane (see jet propulsion) was produced in 1939, and after the end of World War II the development of jetliners brought about a continuous expansion in passenger air travel. In 1969 came the supersonic airliner Concorde.

History
In the 14th century the English philosopher Roger Bacon spoke of constructing an aircraft by means of a hollow globe and liquid fire. He was followed in the 15th century by Albert of Saxony, who also spoke of balloon flight by means of fire in a light sphere. During the 16th and 17th centuries a number of fantastic ideas were put forward; one was that swans' eggs be filled with sulphur or mercury and thereby drawn up to the Sun.

Early ideas
Francisco de Lana in 1670 proposed that four hollow balls made of very thin brass should be emptied of air. To them should be attached a small boat and sail, and in that way a balloon would be contrived which could carry a person. The idea was not feasible, since the globes, made of brass only 0.1 mm thick, would have been crushed by air pressure. But although de Lana saw this difficulty, he argued that their shape would prevent that.

Balloons
It was not until the next century that the real balloon was invented. The beginning of the development of the balloon was the work of two brothers, Joseph and Etienne Montgolfier, who came to the conclusion that a paper bag filled with a ‘substance of a cloud-like nature’ would float in the atmosphere. They made a number of experiments which attracted attention and further efforts from others. Progress with balloons inflated with hot air was made gradually, and the first person-carrying ascent took place in October 1783, when Pilatre de Rozier went up in a Montgolfier captive balloon.

Adding power
It had long been recognized that the difficulty with balloons was navigating through the air. Oars were tried, but were not successful. The first attempt to navigate the balloon by means of a small, light engine came in 1852, the experiment being made by Henri Giffard. From 1897 the development of the airship was the special work of Ferdinand Zeppelin. In 1900 he made his first flight with a dirigible balloon carrying five men. It was made of aluminium, supported by gas-bags, and driven by two motors, each of about 12 kW. His first experiment met with some success, a second, more powerful version was wrecked, and a third met with great success. This airship carried 11 passengers and attained a speed of about 55 kph/34 mph, travelling about 400 km/248 mi in 11 hours, but was wrecked by a storm in 1908, caught fire, and was completely destroyed.

Powered flight
In the late 19th century experiments were being made with soaring machines and hang gliders, chiefly by Otto Lilienthal, who, with an arrangement formed on the plan of birds' wings, attempted to imitate their ‘soaring flight’. Following up Lilienthal's ideas, the Wright brothers produced their first powered aeroplane in 1903. Their first successful machine was simply an aeroplane that flew in a straight line, but this received many modifications; and in 1908 they went to France to carry on experiments, during which Wilbur Wright created a record by remaining in the air for over an hour while carrying a passenger. He also attained a speed of 60 kph/37 mph.

In Europe, at the beginning of the 20th century, France led in aeroplane design and Louis Blériot crossed the English Channel in 1909. This brought aviation much publicity as did the Reims air races of that year. The first powered flight in the UK was made by Samuel Franklin Cody in 1908. In 1912 Sopwith and Bristol both built small biplanes. The first big twin-engined aeroplane was the Handley Page bomber of 1917. The stimulus of World War I (1914–18) and rapid development of the petrol engine led to increased power, and speeds rose to 320 kph/200 mph. Streamlining the body of planes became imperative: the body, wings, and exposed parts were reshaped to reduce drag. Eventually the biplane was superseded by the internally braced monoplane structure, for example, the Hawker Hurricane and Supermarine Spitfire fighters and Avro Lancaster and Boeing Flying Fortress bombers of World War II (1939–45).

Jet aircraft
The German Heinkel 178, built in 1939, was the first jet plane; it was driven, not by a propeller as all planes before it, but by a jet of hot gases. The first British jet aircraft, the Gloster E.28/39, flew from Cranwell, Lincolnshire, on 15 May 1941, powered by a jet engine invented by British engineer Frank Whittle. Twin-jet Meteor fighters were in use by the end of World War II. The rapid development of the jet plane led to enormous increases in power and speed until air-compressibility effects were felt near the speed of sound, which at first seemed to be a flight speed limit (the sound barrier). The sound barrier was first broken in the USA in 1947 by a rocket-powered aircraft piloted by Chuck Yeager. To attain supersonic speed, streamlining the aircraft body became insufficient: wings were swept back, engines buried in wings and tail units, and bodies were even eliminated in all-wing delta designs. In the 1950s the first jet airliners, such as the Comet (first introduced in 1949), were introduced into service. Today jet planes dominate both military and civilian aviation, although many light planes still use piston engines and propellers. The late 1960s saw the introduction of the jumbo jet, and in 1976 the Anglo-French Concorde, which made a transatlantic crossing in under three hours, came into commercial service.

Other developments
During the 1950s and 1960s research was done on V/STOL (vertical and/or short takeoff and landing) aircraft. The British Harrier jet fighter has been the only VTOL aircraft to achieve commercial success, but STOL technology has fed into subsequent generations of aircraft. The 1960s and 1970s also saw the development of variable geometry (‘swing-wing’) aircraft, the wings of which can be swept back in flight to achieve higher speeds. In the 1980s much progress was made in ‘fly-by-wire’ aircraft with computer-aided controls. International partnerships have developed both civilian and military aircraft. The airbus is a wide-bodied airliner built jointly by companies from France, Germany, the UK, the Netherlands, and Spain. The Eurofighter 2000 is a joint project between the UK, Italy, Germany, and Spain. The B-2 bomber (a stealth bomber) developed by the US Air Force in 1989, is almost invisible to radar. The altitude record for a solar-powered plane was set in 1997 by Pathfinder, a 30-m/98-ft wingspan aircraft, which reached 20,528 m/67,349 ft above sea level over Hawaii.

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