"Aeroplane" and "Airplane" redirect here. For other uses, see Aeroplane (disambiguation) and Airplane (disambiguation).
A fixed-wing aircraft is an aircraft capable of flight using wings that generate lift caused by the vehicle's forward airspeed and the shape of the wings. Fixed-wing aircraft are distinct from rotary-wing aircraft in which the wings form a rotor mounted on a spinning shaft andornithopters in which the wings flap in similar manner to a bird.
The wings of a fixed-wing aircraft are not necessarily rigid; kites, hang-gliders and aeroplanes using wing-warping or variable geometry are all regarded as fixed-wing aircraft.
A powered fixed-wing aircraft that gains forward thrust from an engine is typically called an aeroplane, airplane, or simply a plane. Aeroplanes include powered paragliders, powered hang gliders and some ground effect vehicles.
Unpowered fixed-wing aircraft, including free-flying gliders of various kinds and tethered kites, can use moving air to gain height.
Most fixed-wing aircraft are flown by a pilot on board the aircraft, but some are designed to be remotely or computer-controlled.
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[edit]History
Main articles: Aviation history and Early flying machines
[edit]Early kites
Kites were used approximately 2,800 years ago in China, where materials ideal for kite building were readily available. Some authors hold that leaf kites were being flown much earlier in what is now Indonesia, based on their interpretation of cave paintings on Muna Island off Sulawesi.[1] By at least 549 AD paper kites were being flown, as it was recorded in that year a paper kite was used as a message for a rescue mission.[2] Ancient and medieval Chinese sources list other uses of kites for measuring distances, testing the wind, lifting men, signalling, and communication for military operations.[2]
Stories of kites were brought to Europe by Marco Polo towards the end of the 13th century, and kites were brought back by sailors from Japan and Malaysia in the 16th and 17th centuries.[3] Although they were initially regarded as mere curiosities, by the 18th and 19th centuries kites were being used as vehicles for scientific research.[3]
[edit]Gliders and powered models
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).[4][5] This machine may have been suspended for its flight.[6][7]
Some of the earliest recorded attempts with gliders were those by the 9th-century poet Abbas Ibn Firnas and the 11th-century monkEilmer of Malmesbury; both experiments injured their pilots.[8]
In 1799, Sir George Cayley set forth the concept of the modern aeroplane as a fixed-wing flying machine with separate systems for lift, propulsion, and control.[9][10] Cayley was building and flying models of fixed-wing aircraft as early as 1803, and he built a successful passenger-carrying glider in 1853.[11] 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] In 1883, the American John J. Montgomery made a controlled flight in a glider.[citation needed] Other aviators who made similar flights at that time were Otto Lilienthal, Percy Pilcher, and Octave Chanute.
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.[12]
[edit]Powered flight
Sir Hiram Maxim built a craft that weighed 3.5 tons, with a 110-foot (34-meter) wingspan that was powered by two 360-horsepower (270-kW) 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, which Maxim, it is presumed, realized, because he subsequently abandoned work on it.[13]
The Wright brothers' flights in 1903 are recognized by the Fédération Aéronautique Internationale (FAI), the standard setting and record-keeping body foraeronautics, as "the first sustained and controlled heavier-than-air powered flight".[14] By 1905, the Wright Flyer III was capable of fully controllable, stable flight for substantial periods.
In 1906, Brazilian inventor Alberto Santos Dumont designed, built and piloted an airplane that set the first world record recognized by the Aéro-Club de France by flying the 14 bis 220 metres (720 ft) in less than 22 seconds.[15] The flight was certified by the FAI.[16] This was the first controlled flight, to be officially recognised, by a plane able to take off under its own power alone without any auxiliary machine such as a catapult.
The Bleriot VIII design of 1908 was an early aircraft design that had the modern monoplane tractor configuration. 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.[17]
[edit]World War I
World War I served as a testbed for the use of the aircraft as a weapon. Initially seen by the generals as a "toy", aircraft 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 synchronised machine gun-armed fighter aircraft occurred in 1915, by German Luftstreitkräfte Leutnant Kurt Wintgens. Fighter acesappeared; the greatest (by number of air 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 commercial flights took place between the United States and Canada in 1919.
[edit]World War II
Aeroplanes 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 or the American and Japanese aircraft carrier campaigns of the Pacific.
Military gliders were developed and used in several campaigns, but they did not become widely used due to the high casualty rate often encountered. The Focke-Achgelis Fa 330 Bachstelze (Wagtail) rotor kite of 1942 was notable for its use by German submarines.
Before and during the war, both British and German designers were developing jet engines to power aeroplanes. The first jet aircraft to fly, in 1939, was the German Heinkel He 178. In 1943 the first operational jet fighter, the Messerschmitt Me 262, went into service with the German Luftwaffe and later in the war the British Gloster Meteor entered service but never saw action.
[edit]Postwar
In October 1947, the Bell X-1 was the first aircraft to exceed the speed of sound.[citation needed]
In 1948-49, aircraft transported supplies during the Berlin Blockade. New aircraft types, such as the B-52, were produced during the Cold 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 theAirbus A380 in 2005.
[edit]Classes of fixed-wing aircraft
[edit]Airplane/aeroplane
An aeroplane (also known as an airplane in American English or simply a plane) is a powered fixed-wing aircraft that is propelled forward by thrustfrom a jet engine or propeller. Planes come in a variety of sizes, shapes, and wing configurations. The broad spectrum of uses for planes includes recreation, transportation of goods and people, military, and research.
[edit]Etymology and usage
First attested in English in late 19th century, the word aeroplane derives from the French aéroplane, which comes from the Greek ἀήρ (aēr), "air"[18] + either Latin planus, "level",[19] or Greek πλάνος (planos), "wandering".[20][21] "Aeroplane" originally referred just to the wing, as it is a plane moving through the air.[22] In an example of synecdoche, the word for the wing came to refer to the entire aircraft.
In the United Kingdom and most of the Commonwealth, the term 'aeroplane' is used for powered fixed-wing aircraft. In the United States and Canada, the term 'airplane' is usually applied to these aircraft.
[edit]Seaplane
Main article: Seaplane
A seaplane is a fixed-wing aircraft capable of taking off and landing (alighting) on water. Seaplanes that can also operate from dry land are a subclass called amphibian aircraft. These aircraft were sometimes called hydroplanes.[23] Seaplanes and amphibians are usually divided into two categories based on their technological characteristics: floatplanes and flying boats.
- A floatplane is similar in overall design to a land-based aeroplane, except that the wheels at the base of the undercarriage are replaced by floats, allowing the craft to operate from water rather than from dry land.
- A flying boat is a seaplane with a watertight hull forming its fuselage. It differs from a float plane as it does not need additional floats for buoyancy, although it may have small floats to stabilise it on the water. Large seaplanes are usually flying boats.
[edit]Powered gliders
Many forms of glider (see below) may be modified by adding a small power plant. These include:
- Motor glider - a conventional glider or sailplane with an auxiliary power plant that may be used when in flight to increase performance.
- Powered hang glider - a hang glider with a power plant added.
- Powered parachute - a paraglider type of parachute with an integrated airframe, seat, undercarriage and power plant hung beneath.
- Powered paraglider or paramotor - a paraglider with a power plant suspended behind the pilot.
[edit]Ground effect vehicle
Main article: Ground effect vehicle
A ground effect vehicle (GEV) is an aircraft that attains level flight near the surface of the earth, making use of the ground effect - an aerodynamic interaction between the wings and the earth's surface. Some GEVs are able to fly higher out of ground effect (OGE) when required - these are classed as powered fixed-wing aircraft.[24]
[edit]Propulsion
See also: Powered aircraft and Aircraft engine
[edit]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 favoured 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 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.
[edit]Jet engines
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 160 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.
[edit]Electric engines
An electric aircraft runs on electric motors rather than internal combustion engines, with electricity coming from fuel cells, solar cells, ultracapacitors,power beaming,[25] or batteries. Currently, flying electric aircraft are mostly experimental demonstrators, including manned and unmanned aerial vehicles.
[edit]Rocket engines
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.
[edit]Ramjet and scramjet engines
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 and external means of achieving sufficient speed such as a parent aircraft or catapult. TheLockheed D-21 was a Mach 3+ reconnaissance drone that was powered with a ramjet which was launched from a parent aircraft such as the Lockheed A-12. A ramjet works by using the forward motion of the vehicle to force air through the ramjet without resorting to turbines or vanes. Fuel is added and ignited, which heats and expands the air to provides thrust.
Scramjet aircraft are still in the experimental stage. A scramjet is a supersonic ramjet and aside from differences with dealing with internal supersonic airflow works like a conventional ramjet. This type engine requires very high initial speed in order to work. The NASA X-43 is an experimental unmanned scramjet that set a world speed record in 2004 for a jet-powered aircraft with a speed of Mach 9.7, nearly 12,000 kilometres per hour (7,500 mph) at an altitude of about 36,000 metres (118,000 ft).
[edit]Safety
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.[26] Air travel insurance is relatively expensive for this reason- insurers generally use the deaths per journey statistic.[27] 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.[28]
[edit]Glider
Main article: Glider (aircraft)
A Glider is a heavier-than-air craft that is supported in flight by the dynamic reaction of the air against its lifting surfaces, and whose free flight does not depend on an engine. A sailplane is a fixed-wing glider designed for soaring - the ability to gain height in updrafts of air and to fly for long periods.
Gliders are mainly used for recreation, but have also been used for other purposes such as aerodynamics research, warfare and recovering spacecraft.
A Motor glider does have an engine for extending its performance and some have engines powerful enough to take off, but the engine is not used in normal flight.
As is the case with planes, there are a wide variety of glider types differing in the construction of their wings, aerodynamic efficiency, location of the pilot and controls. Perhaps the most familiar type is the toy paper plane.
Large gliders are most commonly launched by a tow-plane or by a winch. Military gliders have been used in war to deliver assault troops, and specialised gliders have been used in atmospheric and aerodynamic research. Rocket-powered aircraft and spaceplanes have also made unpowered landings.
Gliders and sailplanes that are used for the sport of gliding have high aerodynamic efficiency. The highest lift-to-drag ratio is 70:1, though 50:1 is more common. After launch, further energy is obtained through the skillful exploitation of rising air in the atmosphere. Flights of thousands of kilometres at average speeds over 200 km/h have been achieved.
The most numerous unpowered aircraft are hang gliders and paragliders. These are foot-launched and are in general slower, smaller, and less expensive than sailplanes. Hang gliders most often have flexible wings given shape by a frame, though some have rigid wings. Paragliders have no frames in their wings.
Gliders and sailplanes can share a number of features in common with powered aircraft, including many of the same types of fuselage and wing structures. For example the Horten H.IV was a tailless flying wing glider, and the delta wing-shaped Space Shuttle orbiter flew much like a conventional glider in the lower atmosphere. Many gliders also use similar controls and instruments as powered craft.
[edit]Etymology
Glider is the noun form of the verb to glide. It derives from Middle English gliden, which in turn derived from Old English glīdan. The oldest meaning of glide may have denoted a precipitous running or jumping, as opposed to a smooth motion. Scholars are uncertain as to its original derivation, with possible connections to "slide", and "light" having been advanced.[29]
[edit]Types of glider
The main application today of glider aircraft is sport and recreation.
[edit]Glider (sailplane)
Main article: Glider (sailplane)
Gliders were developed from the 1920s for recreational purposes. As pilots began to understand how to use rising air, gliders were developed with a high lift-to-drag ratio. These allowed longer glides to the next source of 'lift', and so increase their chances of flying long distances. This gave rise to the popular sport known as gliding although the term can also be used to refer to merely descending flight.
Gliders were mainly built of wood and metal but the majority now have composite materials using glass, carbon fibre and aramid fibres. To minimise drag, these types have a fuselageand long narrow wings, i.e. a high aspect ratio. Both single-seat and two-seat gliders are available.
Initially training was done by short 'hops' in primary gliders which are very basic aircraft with no cockpit and minimal instruments.[30] Since shortly afterWorld War II training has always been done in two-seat dual control gliders, but high performance two-seaters are also used to share the workload and the enjoyment of long flights. Originally skids were used for landing, but the majority now land on wheels, often retractable. Some gliders, known as motor gliders, are designed for unpowered flight, but can deploy piston, rotary, jet or electric engines.[31] Gliders are classified by the FAI for competitions into glider competition classes mainly on the basis of span and flaps.
A class of ultralight sailplanes, including some known as microlift gliders and some as 'airchairs', has been defined by the FAI based on a maximum weight. They are light enough to be transported easily, and can be flown without licensing in some countries. Ultralight gliders have performance similar to hang gliders, but offer some additional crash safety as the pilot can be strapped in an upright seat within a deformable structure. Landing is usually on one or two wheels which distinguishes these craft from hang gliders. Several commercial ultralight gliders have come and gone, but most current development is done by individual designers and home builders.
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