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"Aeroplane" redirects here. For other uses, see Airplane (disambiguation) or Aeroplane (disambiguation).
Air Berlin B737-700 Dreamliner D-ABBN.jpg
Boeing 737-700 jet airliner

An airplane or aeroplane (informally plane) is a powered, fixed-wing aircraft that is propelled forward by thrust from a jet engine or propeller. 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. Commercial aviation is a massive industry involving the flying of tens of thousands of passengers daily on airliners. Most airplanes are flown by a pilot on board the aircraft, but some are designed to be remotely or computer-controlled.

The Wright brothers invented and flew the first airplane in 1903, recognized as "the first sustained and controlled heavier-than-air powered flight".[1] They built on the works of Sir 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 gliders).[2] Between 1867 and 1896, the German pioneer of human aviation Otto Lilienthal also studied heavier-than-air 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 50 years, from 1958 to 2010.

Etymology and usage

First attested in English in the late 19th century (prior to the first sustained powered flight), the word airplane, like aeroplane, derives from the French aéroplane, which comes from the Greek ἀήρ (aēr), "air"[3] and either Latin planus, "level",[4] or Greek πλάνος (planos), "wandering".[5][6] "Aéroplane" originally referred just to the wing, as it is a plane moving through the air.[7] In an example of synecdoche, the word for the wing came to refer to the entire aircraft.

In the United States and Canada, the term "airplane" is used for powered fixed-wing aircraft. In the United Kingdom and most of the Commonwealth, the term "aeroplane" is usually applied to these aircraft.


Otto Lilienthal in mid-flight, c. 1895


Many stories from antiquity involve flight, such as the Greek legend of Icarus and Daedalus, and the Vimana in ancient Indian epics. Around 400 BC in Greece, Archytas was reputed to have designed and built the first artificial, self-propelled flying device, a bird-shaped model propelled by a jet of what was probably steam, said to have flown some 200 m (660 ft).[8][9] This machine may have been suspended for its flight.[10][11]


In 1799, Sir George Cayley set forth the concept of the modern airplane as a fixed-wing flying machine with separate systems for lift, propulsion, and control.[13][14] Cayley was building and flying models of fixed-wing aircraft as early as 1803, and he built a successful passenger-carrying glider in 1853.[2] 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.[citation needed] Then Alexander F. Mozhaisky also made some innovative designs. In 1883, the American John J. Montgomery made a controlled flight in a glider.[15] Other aviators who made similar flights at that time were Otto Lilienthal, Percy Pilcher, and Octave Chanute.



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.

Early powered flights

The Wright brothers 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".[1] 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, Alberto Santos Dumont made what was claimed to be the first airplane flight unassisted by catapult[18] and set the first world record recognized by the Aéro-Club de France by flying 220 meters (720 ft) in less than 22 seconds.[19] This flight was also certified by the FAI.[20][21]

An early aircraft design that brought together the modern monoplane tractor configuration was the Bleriot 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 Bleriot XI Channel-crossing aircraft of the summer of 1909.[22]

After much work the aircraft, A. Vlaicu nr. 1, was finished in 1909, and was test flown on June 17, 1910. From the first flight the airplane had no need of changes. The plane was made from a single aluminum spar 10 meters long which supported the entire aircraft, making it very easy to fly. Ten planes were made for the Romanian Air Force, being the second-ever military air force in the world.

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. Fighter aces appeared; the greatest (by number of Aerial Combat victories) was Manfred von Richthofen.

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.[citation needed]


Development of jet aircraft

The first 'operational' jet aircraft was the German Heinkel He 178, which was tested in 1939. In 1943, the Messerschmitt Me 262, the first 'operational' jet fighter aircraft, went into service in the German Luftwaffe. In October 1947, the Bell X-1 was the first aircraft to exceed the speed of sound.[23]



Propeller engines

Smaller and older propeller planes make use of reciprocating engines (or piston engines) to turn a propeller to create thrust. The amount of thrust a propeller creates is determined by its disk area - the area in which the blades rotate. If the area is too small, efficiency is poor, and if the area is large, the propeller must rotate at a very low speed to avoid going supersonic and creating a lot of noise, and not much thrust. Because of this limitation, propellers are favored for planes which travel at below mach .5, while jets are a better choice above that speed. Propeller engines may be quieter than jet engines (though not always) and may cost less to purchase or maintain and so remain common on light general aviation aircraft such as the Cessna 172. Larger modern propeller planes such as the Dash 8 use a jet engine to turn the propeller, primarily because an equivalent piston engine in power output would be much larger and more complex.

Jet engines

Main article: Jet engine
The Concorde supersonic transport aircraft

Jet aircraft are propelled by jet engines, which are used because the aerodynamic limitations of propellers do not apply to jet propulsion. These engines are much more powerful than a reciprocating engine for a given size or weight and are comparatively quiet and work well at higher altitude. Most modern jet planes use turbofan jet engines which balance the advantages of a propeller, while retaining the exhaust speed and power of a jet. This is essentially a ducted propeller attached to a jet engine, much like a turboprop, but with a smaller diameter. When installed on an airliner, it is efficient so long as it remains below the speed of sound (or subsonic). Jet fighters and other supersonic aircraft that do not spend a great deal of time supersonic also often use turbofans, but to function, air intake ducting is needed to slow the air down so that when it arrives at the front of the turbofan, it is subsonic. When passing through the engine, it is then re-accelerated back to supersonic speeds. To further boost the power output, fuel is dumped into the exhaust stream, where it ignites. This is called an afterburner and has been used on both pure jet aircraft and turbojet aircraft although it is only normally used on combat aircraft due to the amount of fuel consumed, and even then may only be used for short periods of time. Supersonic airliners (e.g. Concorde) are no longer in use largely because flight at supersonic speed creates a sonic boom which is prohibited in most heavily populated areas, and because of the much higher consumption of fuel supersonic flight requires.

Jet aircraft possess high cruising speeds (700 to 900 km/h (430 to 560 mph)) and high speeds for takeoff and landing (150 to 250 km/h (93 to 155 mph)). Due to the speed needed for takeoff and landing, jet aircraft use flaps and leading edge devices to control of lift and speed. Many also use thrust reversers to slow down the aircraft upon landing.

Electric engines

Main article: Electric motor

An electric aircraft runs on electric motors rather than internal combustion engines, with electricity coming from fuel cells, solar cells, ultracapacitors, power beaming,[24] or batteries. Currently, flying electric aircraft are mostly experimental prototypes, including manned and unmanned aerial vehicles, but there are some production models on the market already.[25]

Rocket engines

Main article: Rocket engine
Bell X-1 in flight, 1947

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. The later North American X-15 broke many speed and altitude records and laid much of the groundwork for later aircraft and spacecraft design. Rocket aircraft are not in common usage today, although rocket-assisted take offs are used for some military aircraft. Recent rocket aircraft include the SpaceShipOne and the XCOR EZ-Rocket.

Ramjet and scramjet engines

Main articles: Ramjet and Scramjet
Artist's concept of X-43A with scramjet attached to the underside

A ramjet is a form of jet engine that contains no major moving parts and can be particularly useful in applications requiring a small and simple engine for high-speed use, such as with missiles. Ramjets require forward motion before they can generate thrust and so are often used in conjunction with other forms of propulsion, or with an external means of achieving sufficient speed. The Lockheed D-21 was a Mach 3+ ramjet-powered reconnaissance drone that was launched from a parent aircraft. A ramjet uses the vehicle's forward motion to force air through the engine without resorting to turbines or vanes. Fuel is added and ignited, which heats and expands the air to provide thrust.

A scramjet is a supersonic ramjet and aside from differences with dealing with internal supersonic airflow works like a conventional ramjet. This type of engine requires a very high initial speed in order to work. The NASA X-43, an experimental unmanned scramjet, set a world speed record in 2004 for a jet-powered aircraft with a speed of Mach 9.7, nearly 7,500 miles per hour (12,100 km/h).

Design and manufacture

SR-71 at Lockheed Skunk Works
Assembly line of the SR-71 Blackbird at Skunk Works, Lockheed Martin’s Advanced Development Programs (ADP).

Most airplanes are constructed by companies with the objective of producing them in quantity for customers. The design and planning process, including safety tests, can last up to four years for small turboprops or longer for larger planes.


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), and in the European Union, European Aviation Safety Agency (EASA). In Canada, the public agency in charge and authorizing the mass production of aircraft is Transport Canada.

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.

Quieter planes are becoming more and more necessary due to the increase in air traffic, particularly over urban areas, as aircraft noise pollution is a major concern.

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.

There are few companies that 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.

When complete, a plane is rigorously inspected to search for imperfections and defects. After approval by inspectors, the plane is put through a series of flight tests to assure that all systems are working correctly and that the plane handles properly. Upon passing these tests, the plane is ready to receive the "final touchups" (internal configuration, painting, etc.), and is then ready for the customer.




Main article: Airframe


Typical structural parts include:

The An-225 Mriya, which can carry a 250-tonne payload, has two vertical stabilisers.
  • A horizontal stabilizer or tailplane, usually mounted at the tail near the vertical stabilizer. The horizontal stabilizer is used to stabilize the plane's pitch (tilt up or down) and mounts the elevators which provide pitch control.
  • Landing gear, a set of wheels, skids, or floats that support the plane while it is on the surface. On seaplanes the bottom of the fuselage or floats (pontoons) support it while on the water. On some planes the landing gear retracts during flight to reduce drag.


Main article: Wing

The wings of a fixed-wing aircraft are static planes extending either side of the aircraft. When the aircraft travels forwards, air flows over the wings which are shaped to create lift. This shape is called an airfoil and is shaped like a birds wing.

Wing structure



Early airplane engines had little power and light weight was very important. Also, early airfoil sections were very thin, and could not have strong frame installed within. So until the 1930s most wings were too light weight 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.

Wing configuration

Main article: Wing configuration
Captured Morane-Saulnier L wire-braced parasol monoplane

The number and shape of the wings varies widely on different types. A given wing plane may be full-span or divided by a central fuselage into port (left) and starboard (right) wings. Occasionally even more wings have been used, with the three-winged triplane achieving some fame in WWI. The four-winged quadruplane and other multiplane designs have had little success.

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.


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.

Two Dassault Mirage G prototypes, one with wings swept

The delta wing is a triangle shape which may be used for a number of 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.



Main article: Fuselage


Wings vs. bodies

Flying wing

Main article: Flying wing
The US-produced B-2 Spirit is a strategic bomber. It has a flying wing configuration and is capable of intercontinental missions

A flying wing is a tailless aircraft which has no definite fuselage. Most of the crew, payload and equipment are housed inside the main wing structure.[26]



Blended wing body

Main article: Blended wing
Computer-generated model of the Boeing X-48



Lifting body

Main article: Lifting body



Empennage and foreplane

Main articles: Empennage and Canard (aeronautics)
Canards on the Saab Viggen

The classic airfoil section wing is unstable in flight and difficult to control. Flexible-wing types often rely on an anchor line or the weight of a pilot hanging beneath to maintain the correct attitude. Some free-flying types use an adapted airfoil that is stable, or other ingenious mechanisms including, most recently, electronic artificial stability.


Some types have a horizontal "canard" foreplane ahead of the main wing, instead of behind it.[26][27][28] This foreplane may contribute to the lift, the trim, or control of the aircraft, or to several of these.

Controls and instruments

A light aircraft (Robin DR400/500) cockpit

Airplanes have complex flight control systems. The main controls allow the pilot to direct the aircraft in the air by controlling the attitude (roll, pitch and yaw) and engine thrust.

On manned aircraft, cockpit instruments provide information to the pilots, including flight data, engine output, navigation, communications and other aircraft systems that may be installed.


Main article: Air safety

When risk is measured by deaths per passenger kilometer, air travel is approximately 10 times safer than travel by bus or rail. However, when using the deaths per journey statistic, air travel is significantly more dangerous than car, rail, or bus travel.[29] Air travel insurance is relatively expensive for this reason- insurers generally use the deaths per journey statistic.[30] There is a significant difference between the safety of airliners and that of smaller private planes, with the per-mile statistic indicating that airliners are 8.3 times safer than smaller planes.[31]

See also


  1. ^ a b FAI News: 100 Years Ago, the Dream of Icarus Became Reality posted 17 December 2003. Retrieved: 5 January 2007.
  2. ^ a b "Cayley, Sir George: Encyclopædia Britannica 2007." Encyclopædia Britannica Online, 25 August 2007.
  3. ^ ἀήρ, Henry George Liddell, Robert Scott, A Greek-English Lexicon, on Perseus
  4. ^ "aeroplane", Merriam-Webster Online Dictionary.
  5. ^ πλάνος, Henry George Liddell, Robert Scott, A Greek-English Lexicon, on Perseus
  6. ^ aeroplane, Oxford Dictionaries
  7. ^ "aeroplane, Oxford English Dictionary online.
  8. ^ Aulus Gellius, "Attic Nights", Book X, 12.9 at LacusCurtius
  9. ^ "Archytas of Tarentum, Technology Museum of Thessaloniki, Macedonia, Greece". Retrieved 2013-05-30. 
  10. ^ "Modern rocketry". Retrieved 2013-05-30. 
  11. ^ "Automata history". Retrieved 2013-05-30. 
  14. ^ "Sir George Cayley (British Inventor and Scientist)". Britannica. Retrieved 26 July 2009. English pioneer of aerial navigation and aeronautical engineering and designer of the first successful glider to carry a human being aloft. Cayley established the modern configuration of an airplane as a fixed-wing flying machine with separate systems for lift, propulsion, and control as early as 1799. 
  15. ^ The Journal of San Diego History, July 1968, Vol. 14, No. 3
  17. ^ Inglis, Amirah. "Hargrave, Lawrence (1850–1915)". Australian Dictionary of Biography 9. Melbourne University Press. Retrieved 5 July 2010. 
  18. ^ "Bernardo Malfitano -". Retrieved 1 April 2015. 
  19. ^ Jones, Ernest. "Santos Dumont in France 1906–1916: The Very Earliest Early Birds.", 25 December 2006. Retrieved: 17 August 2009.
  21. ^ Santos-Dumont: Pionnier de l'aviation, dandy de la Belle Epoque.[dead link]
  24. ^ Power Beaming.
  25. ^ Pipistrel Expands Electric Aircraft Line (2013)
  26. ^ a b Crane, Dale: Dictionary of Aeronautical Terms, third edition, page 224. Aviation Supplies & Academics, 1997. ISBN 1-56027-287-2
  29. ^ The risks of travel.
  30. ^ Flight into danger - 7 August 1999 - New Scientist Space. (7 August 1999).
  31. ^ Mantakos, Harry, Is GA Flying Safer Than Driving?, retrieved 13 May 2012 



External links