An aircraft is a machine that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or by using the dynamic lift of an airfoil, or in a few cases the downward thrust from jet engines. Common examples of aircraft include airplanes, helicopters, airships (including blimps), gliders, and hot air balloons.
The human activity that surrounds aircraft is called aviation. The science of aviation, including designing and building aircraft, is called aeronautics. Crewed aircraft are flown by an onboard pilot, but unmanned aerial vehicles may be remotely controlled or self-controlled by onboard computers. Aircraft may be classified by different criteria, such as lift type, aircraft propulsion, usage and others.
Flying model craft and stories of manned flight go back many centuries, however the first manned ascent – and safe descent – in modern times took place by larger hot-air balloons developed in the 18th century. Each of the two World Wars led to great technical advances. Consequently, the history of aircraft can be divided into five eras:
Aerostats use buoyancy to float in the air in much the same way that ships float on the water. They are characterized by one or more large gasbags or canopies, filled with a relatively low-density gas such as helium, hydrogen, or hot air, which is less dense than the surrounding air. When the weight of this is added to the weight of the aircraft structure, it adds up to the same weight as the air that the craft displaces.
Small hot-air balloons called sky lanterns were first invented in ancient China prior to the 3rd century BC and used primarily in cultural celebrations, and were only the second type of aircraft to fly, the first being kites which were first invented in ancient China over two thousand years ago (see Han Dynasty).
A balloon was originally any aerostat, while the term airship was used for large, powered aircraft designs – usually fixed-wing. In 1919 Frederick Handley Page was reported as referring to "ships of the air," with smaller passenger types as "Air yachts." In the 1930s, large intercontinental flying boats were also sometimes referred to as "ships of the air" or "flying-ships". – though none had yet been built. The advent of powered balloons, called dirigible balloons, and later of rigid hulls allowing a great increase in size, began to change the way these words were used. Huge powered aerostats, characterized by a rigid outer framework and separate aerodynamic skin surrounding the gas bags, were produced, the Zeppelins being the largest and most famous. There were still no fixed-wing aircraft or non-rigid balloons large enough to be called airships, so "airship" came to be synonymous with these aircraft. Then several accidents, such as the Hindenburg disaster in 1937, led to the demise of these airships. Nowadays a "balloon" is an unpowered aerostat and an "airship" is a powered one.
A powered, steerable aerostat is called a dirigible. Sometimes this term is applied only to non-rigid balloons, and sometimes dirigible balloon is regarded as the definition of an airship (which may then be rigid or non-rigid). Non-rigid dirigibles are characterized by a moderately aerodynamic gasbag with stabilizing fins at the back. These soon became known as blimps. During the Second World War, this shape was widely adopted for tethered balloons; in windy weather, this both reduces the strain on the tether and stabilizes the balloon. The nickname blimp was adopted along with the shape. In modern times, any small dirigible or airship is called a blimp, though a blimp may be unpowered as well as powered.
Heavier-than-air aircraft, such as airplanes, must find some way to push air or gas downwards, so that a reaction occurs (by Newton's laws of motion) to push the aircraft upwards. This dynamic movement through the air is the origin of the term aerodyne. There are two ways to produce dynamic upthrust: aerodynamic lift, and powered lift in the form of engine thrust.
Aerodynamic lift involving wings is the most common, with fixed-wing aircraft being kept in the air by the forward movement of wings, and rotorcraft by spinning wing-shaped rotors sometimes called rotary wings. A wing is a flat, horizontal surface, usually shaped in cross-section as an aerofoil. To fly, air must flow over the wing and generate lift. A flexible wing is a wing made of fabric or thin sheet material, often stretched over a rigid frame. A kite is tethered to the ground and relies on the speed of the wind over its wings, which may be flexible or rigid, fixed, or rotary.
With powered lift, the aircraft directs its engine thrust vertically downward. V/STOL aircraft, such as the Harrier Jump Jet and F-35B take off and land vertically using powered lift and transfer to aerodynamic lift in steady flight.
A pure rocket is not usually regarded as an aerodyne, because it does not depend on the air for its lift (and can even fly into space); however, many aerodynamic lift vehicles have been powered or assisted by rocket motors. Rocket-powered missiles that obtain aerodynamic lift at very high speed due to airflow over their bodies are a marginal case.
The forerunner of the fixed-wing aircraft is the kite. Whereas a fixed-wing aircraft relies on its forward speed to create airflow over the wings, a kite is tethered to the ground and relies on the wind blowing over its wings to provide lift. Kites were the first kind of aircraft to fly, and were invented in China around 500 BC. Much aerodynamic research was done with kites before test aircraft, wind tunnels, and computer modelling programs became available.
Practical, powered, fixed-wing aircraft (the aeroplane or airplane) were invented by Wilbur and Orville Wright. Besides the method of propulsion, fixed-wing aircraft are in general characterized by their wing configuration. The most important wing characteristics are:
A variable geometry aircraft can change its wing configuration during flight.
Wing-in-ground-effect vehicles are not considered aircraft. They "fly" efficiently close to the surface of the ground or water, like conventional aircraft during takeoff. An example is the Russian ekranoplan (nicknamed the "Caspian Sea Monster"). Man-powered aircraft also rely on ground effect to remain airborne with a minimal pilot power, but this is only because they are so underpowered—in fact, the airframe is capable of flying higher.
Rotorcraft, or rotary-wing aircraft, use a spinning rotor with aerofoil section blades (a rotary wing) to provide lift. Types include helicopters, autogyros, and various hybrids such as gyrodynes and compound rotorcraft.
Helicopters have a rotor turned by an engine-driven shaft. The rotor pushes air downward to create lift. By tilting the rotor forward, the downward flow is tilted backward, producing thrust for forward flight. Some helicopters have more than one rotor and a few have rotors turned by gas jets at the tips.
Autogyros have unpowered rotors, with a separate power plant to provide thrust. The rotor is tilted backward. As the autogyro moves forward, air blows upward across the rotor, making it spin. This spinning increases the speed of airflow over the rotor, to provide lift. Rotor kites are unpowered autogyros, which are towed to give them forward speed or tethered to a static anchor in high-wind for kited flight.
Cyclogyros rotate their wings about a horizontal axis.
Compound rotorcraft have wings that provide some or all of the lift in forward flight. They are nowadays classified as powered lift types and not as rotorcraft. Tiltrotor aircraft (such as the V-22 Osprey), tiltwing, tailsitter, and coleopter aircraft have their rotors/propellers horizontal for vertical flight and vertical for forward flight.
The smallest aircraft are toys, and—even smaller – nano-aircraft.
The largest aircraft by dimensions and volume (as of 2016) is the 302-foot-long (about 95 meters) British Airlander 10, a hybrid blimp, with helicopter and fixed-wing features, and reportedly capable of speeds up to 90 mph (about 150 km/h), and an airborne endurance of two weeks with a payload of up to 22,050 pounds (11 tons).
The largest aircraft by weight and largest regular fixed-wing aircraft ever built (as of 2016), is the Antonov An-225. That Ukrainian-built 6-engine Russian transport of the 1980s is 84 meters (276 feet) long, with an 88-meter (289 foot) wingspan. It holds the world payload record, after transporting 428,834 pounds (200 tons) of goods, and has recently flown 100-ton loads commercially. Weighing in at somewhere between 1.1 and 1.4 million pounds (550–700 tons) maximum loaded weight, it is also the heaviest aircraft to be built, to date. It can cruise at 500 mph.
The largest military airplanes are the Ukrainian/Russian Antonov An-124 (world's second-largest airplane, also used as a civilian transport), and American Lockheed C-5 Galaxy transport, weighing, loaded, over 765,000 pounds (over 380 tons). The 8-engine, piston/propeller Hughes HK-1 "Spruce Goose," an American World War II wooden flying boat transport—with a greater wingspan (94 meters / 260 feet) than any current aircraft, and a tail-height equal to the tallest (Airbus A380-800 at 24.1 meters / 78 feet) – flew only one short hop in the late 1940s, and never flew out of ground effect.
The largest civilian airplanes, apart from the above-noted An-225 and An-124, are the Airbus Beluga cargo transport derivative of the Airbus A300 jet airliner, the Boeing Dreamlifter cargo transport derivative of the Boeing 747 jet airliner/transport (the 747-200B was, at its creation in the 1960s, the heaviest aircraft ever built, with a maximum weight of 836,000 pounds (over 400 tons)), and the double-decker Airbus A380 "super-jumbo" jet airliner (the world's largest passenger airliner).
The fastest recorded powered aircraft flight and fastest recorded aircraft flight of an air-breathing powered aircraft was of the NASA X-43A Pegasus, a scramjet-powered, hypersonic, lifting body experimental research aircraft, at Mach 9.6 (nearly 7,000 mph). The X-43A set that new mark, and broke its own world record (of Mach 6.3, nearly 5,000 mph, set in March, 2004) on its third and final flight on Nov. 16, 2004.
Prior to the X-43A, the fastest recorded powered airplane flight (and still the record for the fastest manned, powered airplane / fastest manned, non-spacecraft aircraft) was of the North American X-15A-2, rocket-powered airplane at 4,520 mph (7,274 km/h), Mach 6.72, on October 3, 1967. On one flight it reached an altitude of 354,300 feet.
The fastest known, production aircraft (other than rockets and missiles) currently or formerly operational (as of 2016) are:
Gliders are heavier-than-air aircraft that do not employ propulsion once airborne. Take-off may be by launching forward and downward from a high location, or by pulling into the air on a tow-line, either by a ground-based winch or vehicle, or by a powered "tug" aircraft. For a glider to maintain its forward air speed and lift, it must descend in relation to the air (but not necessarily in relation to the ground). Many gliders can 'soar' – gain height from updrafts such as thermal currents. The first practical, controllable example was designed and built by the British scientist and pioneer George Cayley, whom many recognise as the first aeronautical engineer. Common examples of gliders are sailplanes, hang gliders and paragliders.
Balloons drift with the wind, though normally the pilot can control the altitude, either by heating the air or by releasing ballast, giving some directional control (since the wind direction changes with altitude). A wing-shaped hybrid balloon can glide directionally when rising or falling; but a spherically shaped balloon does not have such directional control.
Kites are aircraft that are tethered to the ground or other object (fixed or mobile) that maintains tension in the tether or kite line; they rely on virtual or real wind blowing over and under them to generate lift and drag. Kytoons are balloon-kite hybrids that are shaped and tethered to obtain kiting deflections, and can be lighter-than-air, neutrally buoyant, or heavier-than-air.
Powered aircraft have one or more onboard sources of mechanical power, typically aircraft engines although rubber and manpower have also been used. Most aircraft engines are either lightweight piston engines or gas turbines. Engine fuel is stored in tanks, usually in the wings but larger aircraft also have additional fuel tanks in the fuselage.
Propeller aircraft use one or more propellers (airscrews) to create thrust in a forward direction. The propeller is usually mounted in front of the power source in tractor configuration but can be mounted behind in pusher configuration. Variations of propeller layout include contra-rotating propellers and ducted fans.
Many kinds of power plant have been used to drive propellers. Early airships used man power or steam engines. The more practical internal combustion piston engine was used for virtually all fixed-wing aircraft until World War II and is still used in many smaller aircraft. Some types use turbine engines to drive a propeller in the form of a turboprop or propfan. Human-powered flight has been achieved, but has not become a practical means of transport. Unmanned aircraft and models have also used power sources such as electric motors and rubber bands.
Turbojet and turbofan engines use a spinning turbine to drive one or more fans, which provide additional thrust. An afterburner may be used to inject extra fuel into the hot exhaust, especially on military "fast jets". Use of a turbine is not absolutely necessary: other designs include the pulse jet and ramjet. These mechanically simple designs cannot work when stationary, so the aircraft must be launched to flying speed by some other method. Other variants have also been used, including the motorjet and hybrids such as the Pratt & Whitney J58, which can convert between turbojet and ramjet operation.
Compared to propellers, jet engines can provide much higher thrust, higher speeds and, above about 40,000 ft (12,000 m), greater efficiency. They are also much more fuel-efficient than rockets. As a consequence nearly all large, high-speed or high-altitude aircraft use jet engines.
Some rotorcraft, such as helicopters, have a powered rotary wing or rotor, where the rotor disc can be angled slightly forward so that a proportion of its lift is directed forwards. The rotor may, like a propeller, be powered by a variety of methods such as a piston engine or turbine. Experiments have also used jet nozzles at the rotor blade tips.
Aircraft are designed according to many factors such as customer and manufacturer demand, safety protocols and physical and economic constraints. For many types of aircraft the design process is regulated by national airworthiness authorities.
The key parts of an aircraft are generally divided into three categories:
The approach to structural design varies widely between different types of aircraft. Some, such as paragliders, comprise only flexible materials that act in tension and rely on aerodynamic pressure to hold their shape. A balloon similarly relies on internal gas pressure but may have a rigid basket or gondola slung below it to carry its payload. Early aircraft, including airships, often employed flexible doped aircraft fabric covering to give a reasonably smooth aeroshell stretched over a rigid frame. Later aircraft employed semi-monocoque techniques, where the skin of the aircraft is stiff enough to share much of the flight loads. In a true monocoque design there is no internal structure left.
The key structural parts of an aircraft depend on what type it is.
Lighter-than-air types are characterised by one or more gasbags, typically with a supporting structure of flexible cables or a rigid framework called its hull. Other elements such as engines or a gondola may also be attached to the supporting structure.
Heavier-than-air types are characterised by one or more wings and a central fuselage. The fuselage typically also carries a tail or empennage for stability and control, and an undercarriage for takeoff and landing. Engines may be located on the fuselage or wings. On a fixed-wing aircraft the wings are rigidly attached to the fuselage, while on a rotorcraft the wings are attached to a rotating vertical shaft. Smaller designs sometimes use flexible materials for part or all of the structure, held in place either by a rigid frame or by air pressure. The fixed parts of the structure comprise the airframe.
The flight envelope of an aircraft refers to its capabilities in terms of airspeed and load factor or altitude. The term can also refer to other measurements such as maneuverability. When a craft is pushed, for instance by diving it at high speeds, it is said to be flown outside the envelope, something considered unsafe.
For a powered aircraft the time limit is determined by the fuel load and rate of consumption.
For an unpowered aircraft, the maximum flight time is limited by factors such as weather conditions and pilot endurance. Many aircraft types are restricted to daylight hours, while balloons are limited by their supply of lifting gas. The range can be seen as the average ground speed multiplied by the maximum time in the air.
Flight dynamics is the science of air vehicle orientation and control in three dimensions. The three critical flight dynamics parameters are the angles of rotation around three axes which pass through the vehicle's center of gravity, known as pitch, roll, and yaw.
Flight dynamics is concerned with the stability and control of an aircraft's rotation about each of these axes.
An aircraft that is unstable tends to diverge from its current flight path and so is difficult to fly. A very stable aircraft tends to stay on its current flight path and is difficult to manoeuvre—so it is important for any design to achieve the desired degree of stability. Since the widespread use of digital computers, it is increasingly common for designs to be inherently unstable and rely on computerised control systems to provide artificial stability.
A fixed wing is typically unstable in pitch, roll, and yaw. Pitch and yaw stabilities of conventional fixed wing designs require horizontal and vertical stabilisers, which act similarly to the feathers on an arrow. These stabilizing surfaces allow equilibrium of aerodynamic forces and to stabilise the flight dynamics of pitch and yaw. They are usually mounted on the tail section (empennage), although in the canard layout, the main aft wing replaces the canard foreplane as pitch stabilizer. Tandem wing and Tailless aircraft rely on the same general rule to achieve stability, the aft surface being the stabilising one.
A rotary wing is typically unstable in yaw, requiring a vertical stabiliser.
A balloon is typically very stable in pitch and roll due to the way the payload is hung underneath.
Flight control surfaces enable the pilot to control an aircraft's flight attitude and are usually part of the wing or mounted on, or integral with, the associated stabilizing surface. Their development was a critical advance in the history of aircraft, which had until that point been uncontrollable in flight.
Aerospace engineers develop control systems for a vehicle's orientation (attitude) about its center of mass. The control systems include actuators, which exert forces in various directions, and generate rotational forces or moments about the aerodynamic center of the aircraft, and thus rotate the aircraft in pitch, roll, or yaw. For example, a pitching moment is a vertical force applied at a distance forward or aft from the aerodynamic center of the aircraft, causing the aircraft to pitch up or down. Control systems are also sometimes used to increase or decrease drag, for example to slow the aircraft to a safe speed for landing.
The two main aerodynamic forces acting on any aircraft are lift supporting it in the air and drag opposing its motion. Control surfaces or other techniques may also be used to affect these forces directly, without inducing any rotation.
Aircraft permit long distance, high speed travel and may be a more fuel efficient mode of transportation in some circumstances. Aircraft have environmental and climate impacts beyond fuel efficiency considerations, however. They are also relatively noisy compared to other forms of travel and high altitude aircraft generate contrails, which experimental evidence suggests may alter weather patterns.
Aircraft are produced in several different types optimized for various uses; military aircraft, which includes not just combat types but many types of supporting aircraft, and civil aircraft, which include all non-military types, experimental and model.
A military aircraft is any aircraft that is operated by a legal or insurrectionary armed service of any type. Military aircraft can be either combat or non-combat:
Most military aircraft are powered heavier-than-air types. Other types such as gliders and balloons have also been used as military aircraft; for example, balloons were used for observation during the American Civil War and World War I, and military gliders were used during World War II to land troops.
Civil aircraft divide into commercial and general types, however there are some overlaps.
Commercial aircraft include types designed for scheduled and charter airline flights, carrying passengers, mail and other cargo. The larger passenger-carrying types are the airliners, the largest of which are wide-body aircraft. Some of the smaller types are also used in general aviation, and some of the larger types are used as VIP aircraft.
General aviation is a catch-all covering other kinds of private (where the pilot is not paid for time or expenses) and commercial use, and involving a wide range of aircraft types such as business jets (bizjets), trainers, homebuilt, gliders, warbirds and hot air balloons to name a few. The vast majority of aircraft today are general aviation types.
An experimental aircraft is one that has not been fully proven in flight, or that carries an FAA Special Airworthiness Certificate called an Experimental Certificate. Often, this implies that the aircraft is testing new aerospace technologies, though the term also refers to amateur and kit-built aircraft, many of which are based on proven designs.
A model aircraft is a small unmanned type made to fly for fun, for static display, for aerodynamic research or for other purposes. A scale model is a replica of some larger design.
The Airbus A320 family consists of short- to medium-range, narrow-body, commercial passenger twin-engine jet airliners manufactured by Airbus. The family includes the A318, A319, A320 and A321, as well as the ACJ business jet. The A320s are also named A320ceo (current engine option) after the introduction of the A320neo (new engine option). Final assembly of the family takes place in Toulouse, France, and Hamburg, Germany. A plant in Tianjin, China, has also been producing aircraft for Chinese airlines since 2009, while a final assembly facility in Mobile, Alabama, United States, delivered its first A321 in April 2016. The aircraft family can accommodate up to 236 passengers and has a range of 3,100 to 12,000 km (1,700 to 6,500 nmi), depending on model.
The first member of the A320 family—the A320—was launched in March 1984, first flew on 22 February 1987, and was first delivered in March 1988 to launch customer Air France. The family was extended to include the A321 (first delivered 1994), the A319 (1996), and the A318 (2003). The A320 family pioneered the use of digital fly-by-wire flight control systems, as well as side-stick controls, in commercial aircraft. There has been a continuous improvement process since introduction.
As of 31 December 2018, a total of 8,605 Airbus A320-family aircraft have been delivered, of which 8,217 are in service. In addition, another 6.056 airliners are on firm order. It ranked as the world's fastest-selling jet airliner family according to records from 2005 to 2007, and as the best-selling single-generation aircraft programme. The A320 family has proved popular with airlines including low-cost carriers such as EasyJet, which ordered A319s and A320s to replace its ageing 737 fleet. As of December 2018, American Airlines was the largest operator of the Airbus A320 family aircraft, operating 397 aircraft. The aircraft family competes directly with the 737 and has competed with the 717, 757, and the MD-80/MD-90.
In December 2010, Airbus announced a new generation of the A320 family, the A320neo (new engine option). The A320neo offers new, more efficient engines, combined with airframe improvements and the addition of winglets, named Sharklets by Airbus. The aircraft will deliver fuel savings of up to 15%. As of December 2018, a total of 6,526 A320neo family aircraft had been ordered by more than 70 airlines, making it the fastest selling commercial aircraft. The first A320neo was delivered to Lufthansa on 20 January 2016 and it entered service on 25 January 2016.Airbus A380
The Airbus A380 is the world's largest passenger airliner, a wide-body aircraft manufactured by Airbus.
Airbus studies started in 1988 and the project was announced in 1990 to challenge the dominance of the Boeing 747 in the long haul market.
The A3XX project was presented in 1994; Airbus launched the €9.5 billion ($10.7 billion) A380 programme on 19 December 2000.
The first prototype was unveiled in Toulouse on 18 January 2005,
with its first flight on 27 April 2005.
It obtained its EASA and FAA type certificates on 12 December 2006.
Difficulties in electrical wiring caused a two-year delay and the development cost ballooned to €18 billion.
It was first delivered to Singapore Airlines on 15 October 2007 and entered service on 25 October.
Production peaked at 30 per year in 2012 and 2014. However, Airbus concedes that its $25 billion investment for the aircraft cannot be recouped.
On 14 February 2019, after Emirates reduced its last orders in favour of the A350 and the A330neo, Airbus announced that production would end by 2021.
The full-length double-deck aircraft has a range of 8,000 nmi (14,800 km) and is typically configured for 575 passengers, though it can be fitted with up to 853 seats.
It is powered by four Engine Alliance GP7200 or Rolls-Royce Trent 900 turbofans.
As of January 2019, Airbus has received 313 firm orders and delivered 234 aircraft; Emirates is the biggest A380 customer with 123 ordered, of which 109 have been delivered.Aircraft carrier
An aircraft carrier is a warship that serves as a seagoing airbase, equipped with a full-length flight deck and facilities for carrying, arming, deploying, and recovering aircraft. Typically, it is the capital ship of a fleet, as it allows a naval force to project air power worldwide without depending on local bases for staging aircraft operations. Carriers have evolved since their inception in the early twentieth century from wooden vessels used to deploy balloons to nuclear-powered warships that carry numerous fighters, strike aircraft, helicopters, and other types of aircraft. While heavier aircraft such as fixed-wing gunships and bombers have been launched from aircraft carriers, it is currently not possible to land them. By its diplomatic and tactical power, its mobility, its autonomy and the variety of its means, the aircraft carrier is often the centerpiece of modern combat fleets. Tactically or even strategically, it replaced the battleship in the role of flagship of a fleet. One of its great advantages is that, by sailing in international waters, it does not interfere with any territorial sovereignty and thus obviates the need for overflight authorizations from third party countries, reduce the times and transit distances of aircraft and therefore significantly increase the time of availability on the combat zone.
There is no single definition of an "aircraft carrier", and modern navies use several variants of the type. These variants are sometimes categorized as sub-types of aircraft carriers, and sometimes as distinct types of naval aviation-capable ships. Aircraft carriers may be classified according to the type of aircraft they carry and their operational assignments. Admiral Sir Mark Stanhope, RN, former First Sea Lord (head) of the Royal Navy, has said, "To put it simply, countries that aspire to strategic international influence have aircraft carriers." Henry Kissinger, while United States Secretary of State, also said: "An aircraft carrier is 100,000 tons of diplomacy".As of February 2019, there are 41 active aircraft carriers in the world operated by thirteen navies. The United States Navy has 11 large nuclear-powered fleet carriers—carrying around 80 fighter jets each—the largest carriers in the world; the total combined deckspace is over twice that of all other nations combined. As well as the aircraft carrier fleet, the U.S. Navy has nine amphibious assault ships used primarily for helicopters, although these also carry up to 20 vertical or short take-off and landing (V/STOL) fighter jets and are similar in size to medium-sized fleet carriers. China, France, India, Russia, and the UK each operate a single large/medium-size carrier, with capacity from 30 to 60 fighter jets. Italy operates two light fleet carriers and Spain operates one. Helicopter carriers are operated by Japan (4), France (3), Australia (2), Egypt (2), Brazil (1), South Korea (1), and Thailand (1). Future aircraft carriers are under construction or in planning by Brazil, China, India, Russia, the United Kingdom, and the United States.Aviation accidents and incidents
In aviation, an accident is defined by the Convention on International Civil Aviation Annex 13 as an occurrence associated with the operation of an aircraft, which takes place from the time any person boards the aircraft with the intention of flight until all such persons have disembarked, and in which a) a person is fatally or seriously injured, b) the aircraft sustains significant damage or structural failure, or c) the aircraft goes missing or becomes completely inaccessible. Annex 13 defines an incident as an occurrence, other than an accident, associated with the operation of an aircraft that affects or could affect the safety of operation.A hull loss occurs if an aircraft is destroyed, damaged beyond repair, lost, or becomes completely inaccessible.The first fatal aviation accident was the crash of a Rozière balloon near Wimereux, France, on June 15, 1785, killing the balloon's inventor, Jean-François Pilâtre de Rozier, and the other occupant, Pierre Romain. The first involving a powered aircraft was the crash of a Wright Model A aircraft at Fort Myer, Virginia, in the United States on September 17, 1908, injuring its co-inventor and pilot, Orville Wright, and killing the passenger, Signal Corps Lieutenant Thomas Selfridge.Boeing
The Boeing Company () is an American multinational corporation that designs, manufactures, and sells airplanes, rotorcraft, rockets, satellites, and missiles worldwide. The company also provides leasing and product support services. Boeing is among the largest global aircraft manufacturers; it is the fifth-largest defense contractor in the world based on 2017 revenue, and is the largest exporter in the United States by dollar value. Boeing stock is included in the Dow Jones Industrial Average.
Boeing was founded by William Boeing on July 15, 1916, in Seattle, Washington. The present corporation is the result of merger of Boeing with McDonnell Douglas on August 1, 1997. Former Boeing's chair and CEO Philip M. Condit continued as the chair and CEO of the new Boeing, while Harry Stonecipher, former CEO of McDonnell Douglas, became the president and chief operating officer of the newly merged company.The Boeing Company has its corporate headquarters in Chicago, Illinois. The company is led by President and CEO Dennis Muilenburg. Boeing is organized into five primary divisions: Boeing Commercial Airplanes (BCA); Boeing Defense, Space & Security (BDS); Engineering, Operations & Technology; Boeing Capital; and Boeing Shared Services Group. In 2017, Boeing recorded $93.3 billion in sales, ranked 24th on the Fortune magazine "Fortune 500" list (2018), ranked 64th on the "Fortune Global 500" list (2018), and ranked 25th on the "World's Most Admired Companies" list (2018).Boeing 707
The Boeing 707 is a mid-sized, long-range, narrow-body, four-engine jet airliner built by Boeing Commercial Airplanes from 1958 to 1979. Its name is commonly pronounced as "seven oh seven". Versions of the aircraft have a capacity from 140 to 219 passengers and a range of 2,500 to 5,750 nautical miles (2,880 to 6,620 mi; 4,630 to 10,650 km).Developed as Boeing's first jet airliner, the 707 is a swept-wing design with podded engines. Although it was not the first jetliner in service, the 707 was the first to be commercially successful. Dominating passenger air transport in the 1960s and remaining common through the 1970s, the 707 is generally credited with ushering in the Jet Age. It established Boeing as one of the largest manufacturers of passenger aircraft, and led to the later series of airliners with "7x7" designations. The later 720, 727, 737, and 757 share elements of the 707's fuselage design.
The 707 was developed from the Boeing 367-80, a prototype jet first flown in 1954. A larger fuselage cross-section and other modifications resulted in the initial-production 707-120, powered by Pratt & Whitney JT3C turbojet engines, which first flew on December 20, 1957. Pan American World Airways began regular 707 service on October 26, 1958. Later derivatives included the shortened long-range 707-138 and the stretched 707-320, both of which entered service in 1959. A smaller short-range variant, the 720, was introduced in 1960. The 707-420, a version of the stretched 707 with Rolls-Royce Conway turbofans, debuted in 1960, while Pratt & Whitney JT3D turbofans debuted on the 707-120B and 707-320B models in 1961 and 1962, respectively.
The 707 has been used on domestic, transcontinental, and transatlantic flights, and for cargo and military applications. A convertible passenger-freighter model, the 707-320C, entered service in 1963, and passenger 707s have been modified to freighter configurations. Military derivatives include the E-3 Sentry airborne reconnaissance aircraft and the C-137 Stratoliner VIP transports. Boeing produced and delivered 1,011 airliners including the smaller 720 series; over 800 military versions were also produced.Boeing 737
The Boeing 737 is a short- to medium-range twinjet narrow-body airliner developed and manufactured by Boeing Commercial Airplanes in the United States. Originally developed as a shorter, lower-cost twin-engine airliner derived from the 707 and 727, the 737 has developed into a family of thirteen passenger models with capacities from 85 to 215 passengers. The 737 is Boeing's only narrow-body airliner in production, with the 737 Next Generation (-700, -800, and -900ER) and the re-engined and updated 737 MAX variants currently being built.
The 737 was originally envisioned in 1964. The initial 737-100 made its first flight in April 1967, and entered airline service in February 1968 at Lufthansa. Next, the lengthened 737-200 entered service in April 1968. In the 1980s Boeing launched the longer 737-300, −400, and −500 variants (referred to as the Boeing 737 Classic series) featuring CFM56 turbofan engines and wing improvements.
The Boeing 737 Next Generation (NG) was introduced in the 1990s, with a redesigned, increased span wing, upgraded "glass" cockpit, and new interior. The 737 NG comprises the 737-600, −700, −800, and −900 variants, with lengths ranging from 31.09 to 42.06 m (102 to 138 ft). Boeing Business Jet versions of the 737 NG are also produced. The 737 was revised again in the 2010s for greater efficiency, with the 737 MAX series featuring CFM LEAP-1B engines and improved winglets. The 737 MAX entered service in 2017.
The 737 series is the highest-selling commercial jetliner in history. The 737 has been continuously manufactured since 1967; the 10,000th was rolled out on March 13, 2018, a MAX 8 destined for Southwest Airlines, and over 4,600 orders are pending. Assembly of the 737 is performed at the Boeing Renton Factory in Renton, Washington. Many 737s serve markets previously filled by 707, 727, 757, DC-9, and MD-80/MD-90 airliners, and the aircraft currently competes primarily with the Airbus A320 family. As of 2006, there were an average of 1,250 Boeing 737s airborne at any given time, with two either departing or landing somewhere every five seconds.Boeing 747
The Boeing 747 is an American wide-body commercial jet airliner and cargo aircraft, often referred to by its original nickname, "Jumbo Jet". Its distinctive hump upper deck along the forward part of the aircraft has made it one of the most recognizable aircraft, and it was the first wide-body airplane produced. Manufactured by Boeing's Commercial Airplane unit in the United States, the 747 was originally envisioned to have 150 percent greater capacity than the Boeing 707, a common large commercial aircraft of the 1960s. First flown commercially in 1970, the 747 held the passenger capacity record for 37 years.The quadjet 747 uses a double-deck configuration for part of its length and is available in passenger, freighter and other versions. Boeing designed the 747's hump-like upper deck to serve as a first–class lounge or extra seating, and to allow the aircraft to be easily converted to a cargo carrier by removing seats and installing a front cargo door. Boeing expected supersonic airliners—the development of which was announced in the early 1960s—to render the 747 and other subsonic airliners obsolete, while the demand for subsonic cargo aircraft would remain robust well into the future. Though the 747 was expected to become obsolete after 400 were sold, it exceeded critics' expectations with production surpassing 1,000 in 1993. By July 2018, 1,546 aircraft had been built, with 22 of the 747-8 variants remaining on order. As of January 2017, the 747 has been involved in 60 hull losses, resulting in 3,722 fatalities.The 747-400, the most common variant in service, has a high-subsonic cruise speed of Mach 0.85–0.855 (up to 570 mph or 920 km/h) with an intercontinental range of 7,260 nautical miles (8,350 statute miles or 13,450 km). The 747-400 can accommodate 416 passengers in a typical three-class layout, 524 passengers in a typical two-class layout, or 660 passengers in a high–density one-class configuration. The newest version of the aircraft, the 747-8, is in production and received certification in 2011. Deliveries of the 747-8F freighter version began in October 2011; deliveries of the 747-8I passenger version began in May 2012.Boeing 777
The Boeing 777 (Triple Seven) is a long-range wide-body twin-engine jet airliner developed and manufactured by Boeing Commercial Airplanes. It is the world's largest twinjet and has a typical seating capacity of 314 to 396 passengers, with a range of 5,240 to 8,555 nautical miles (9,704 to 15,844 km). Commonly referred to as the "Triple Seven", its distinguishing features include the large–diameter turbofan engines, long raked wings, six wheels on each main landing gear, fully circular fuselage cross-section, and a blade-shaped tail cone. Developed in consultation with eight major airlines, the 777 was designed to replace older wide-body airliners and bridge the capacity difference between Boeing's 767 and 747. As Boeing's first fly-by-wire airliner, it has computer-mediated controls. It was also the first commercial aircraft to be designed entirely with computer-aided design.
The 777 is produced in two fuselage lengths as of 2018. The original 777-200 variant entered commercial service in 1995, followed by the extended-range 777-200ER in 1997. The stretched 777-300, which is 33.25 ft (10.1 m) longer, followed in 1998. The initial 777-200, extended-range -200ER, and -300 versions are equipped with General Electric GE90, Pratt & Whitney PW4000, or Rolls-Royce Trent 800 engines. They have since been collectively referred to as 777 Classics. The extended-range 777-300ER and ultra long-range 777-200LR variants entered service in 2004 and 2006 respectively, while the 777F, a freighter version, debuted in February 2009; these second-generation variants all feature high-output GE90 engines and extended raked wingtips. The 777-200LR is one of the world's longest-range airliners, able to fly more than halfway around the globe and holds the record for the longest distance flown non-stop by a commercial aircraft. In November 2013, Boeing announced the development of the third-generation of the 777, the 777X, consisting of the 777-8 and 777-9 variants. The 777X features composite folding wings and GE9X engines plus further technologies developed for the Boeing 787, and is scheduled to enter service by 2020.
The 777 first entered commercial service with United Airlines on June 7, 1995. The 777 has received more orders than any other wide-body airliner; as of January 2019, more than 60 customers had placed orders for 2,013 aircraft of all variants, with 1,582 delivered. The most common and successful variant is the 777-300ER with 799 delivered and 844 orders; Emirates operates the largest 777 fleet, with 163 passenger and freighter aircraft as of July 2018. The 777 has been involved in six hull losses as of October 2016; the Asiana Airlines Flight 214 accident in July 2013 was its first fatal crash in 18 years of service, and the shootdown of Malaysia Airlines Flight 17 in July 2014 is its deadliest crash as of January 2019.
The 777 ranks as one of Boeing's best-selling models, making it the most-produced Boeing wide-body jet, surpassing the Boeing 747. Airlines have acquired the type as a comparatively fuel-efficient alternative to other wide-body jets and have increasingly deployed the aircraft on long-haul transoceanic routes. Direct market competitors include the Airbus A330-300, the Airbus A350 XWB, and the out-of-production A340 and McDonnell Douglas MD-11. The 787 Dreamliner, which entered service in 2011, shares some design features with the 777.General Dynamics F-16 Fighting Falcon
The General Dynamics F-16 Fighting Falcon is a single-engine supersonic multirole fighter aircraft originally developed by General Dynamics (now Lockheed Martin) for the United States Air Force (USAF). Designed as an air superiority day fighter, it evolved into a successful all-weather multirole aircraft. Over 4,500 aircraft have been built since production was approved in 1976. Although no longer being purchased by the U.S. Air Force, improved versions are being built for export customers. In 1993, General Dynamics sold its aircraft manufacturing business to the Lockheed Corporation, which in turn became part of Lockheed Martin after a 1995 merger with Martin Marietta.The Fighting Falcon's key features include a frameless bubble canopy for better visibility, side-mounted control stick to ease control while maneuvering, a ejection seat reclined 30 degrees from vertical to reduce the effect of g-forces on the pilot, and the first use of a relaxed static stability/fly-by-wire flight control system which helps to make it a nimble aircraft. The F-16 has an internal M61 Vulcan cannon and 11 locations for mounting weapons and other mission equipment. The F-16's official name is "Fighting Falcon", but "Viper" is commonly used by its pilots and crews, due to a perceived resemblance to a viper snake as well as the Colonial Viper starfighter on Battlestar Galactica which aired around when the F-16 entered service.In addition to active duty in the U.S. Air Force, Air Force Reserve Command, and Air National Guard units, the aircraft is also used by the USAF aerial demonstration team, the U.S. Air Force Thunderbirds, and as an adversary/aggressor aircraft by the United States Navy. The F-16 has also been procured to serve in the air forces of 25 other nations. As of 2015, it is the world's most numerous fixed-wing aircraft in military service.Junkers Ju 87
The Junkers Ju 87 or Stuka (from Sturzkampfflugzeug, "dive bomber") was a German dive bomber and ground-attack aircraft. Designed by Hermann Pohlmann, it first flew in 1935. The Ju 87 made its combat debut in 1937 with the Luftwaffe's Condor Legion during the Spanish Civil War and served the Axis forces in World War II.
The aircraft was easily recognisable by its inverted gull wings and fixed spatted undercarriage. Upon the leading edges of its faired main gear legs were mounted the Jericho-Trompete (Jericho trumpet) wailing sirens, becoming the propaganda symbol of German air power and the blitzkrieg victories of 1939–1942. The Stuka's design included several innovations, including automatic pull-up dive brakes under both wings to ensure that the aircraft recovered from its attack dive even if the pilot blacked out from the high g-forces.
The Stuka operated with considerable success in close air support and anti-shipping at the outbreak of World War II. It led air assaults in the invasion of Poland in September 1939. Stukas were critical to the rapid conquest of Norway, the Netherlands, Belgium and France in 1940. Sturdy, accurate, and very effective against ground targets, the Stuka was, like many other dive bombers of the period, vulnerable to fighter aircraft. During the Battle of Britain its lack of manoeuvrability, speed and defensive armament meant that it required a heavy fighter escort to operate effectively. After the Battle of Britain the Stuka was used in the Balkans Campaign, the African and Mediterranean theatres and the early stages of the Eastern Front where it was used for general ground support, as an effective specialised anti-tank aircraft and in an anti-shipping role. Once the Luftwaffe lost air superiority, the Stuka became an easy target for enemy fighter aircraft on all fronts. It was produced until 1944 for lack of a better replacement. By then ground-attack versions of the Focke-Wulf Fw 190 had largely replaced the Stuka, but Stukas remained in service until the end of the war.
An estimated 6,500 Ju 87s of all versions were built between 1936 and August 1944.
Oberst Hans-Ulrich Rudel was the most successful Stuka ace and the most highly decorated German serviceman of the Second World War.Lockheed Martin F-22 Raptor
The Lockheed Martin F-22 Raptor is a fifth-generation, single-seat, twin-engine, all-weather stealth tactical fighter aircraft developed for the United States Air Force (USAF). The result of the USAF's Advanced Tactical Fighter program, the aircraft was designed primarily as an air superiority fighter, but also has ground attack, electronic warfare, and signal intelligence capabilities. The prime contractor, Lockheed Martin, built most of the F-22's airframe and weapons systems and conducted final assembly, while Boeing provided the wings, aft fuselage, avionics integration, and training systems.
The aircraft was variously designated F-22 and F/A-22 before it formally entered service in December 2005 as the F-22A. After a protracted development and despite operational issues, the USAF considered the F-22 critical to its tactical air power. When the aircraft was introduced, the USAF stated that the aircraft was unmatched by any known or projected fighter. The Raptor's combination of stealth, aerodynamic performance, and situational awareness gives the aircraft unprecedented air combat capabilities.The high cost of the aircraft, a lack of clear air-to-air missions due to delays in Russian and Chinese fighter programs, a ban on exports, and development of the more versatile F-35 led to the end of F-22 production. A final procurement tally of 187 operational production aircraft was established in 2009, and the last F-22 was delivered to the USAF in 2012.Lockheed Martin F-35 Lightning II
The Lockheed Martin F-35 Lightning II is a family of single-seat, single-engine, all-weather stealth multirole fighters. The fifth-generation combat aircraft is designed to perform ground-attack and air-superiority missions. It has three main models: the F-35A conventional takeoff and landing (CTOL) variant, the F-35B short take-off and vertical-landing (STOVL) variant, and the F-35C carrier-based catapult-assisted take-off but arrested recovery (CATOBAR) variant. The F-35 descends from the Lockheed Martin X-35, the winning design of the Joint Strike Fighter (JSF) program. It is built by Lockheed and many subcontractors, including Northrop Grumman, Pratt & Whitney, and BAE Systems.
The United States principally funds F-35 development, with additional funding from other NATO members and close U.S. allies, including the United Kingdom, Italy, Australia, Canada, Norway, Denmark, the Netherlands, and Turkey. These funders generally receive subcontracts to manufacture components for the aircraft; for example, Turkey is the sole supplier of several F-35 parts. Several other countries have ordered, or are considering ordering, the aircraft.
As the largest and most expensive military program, the F-35 is the subject of much scrutiny and criticism in the U.S. and in other countries. In 2013 and 2014, critics argued that the plane was "plagued with design flaws", with many blaming the procurement process in which Lockheed was allowed "to design, test, and produce the F-35 all at the same time," instead of identifying and fixing "defects before firing up its production line". By 2014, the program was "$163 billion over budget [and] seven years behind schedule". Critics also contend that the program's high sunk costs and political momentum make it "too big to kill".The F-35 first flew on 15 December 2006. In July 2015, the United States Marines declared its first squadron of F-35B fighters ready for deployment;. However, the DOD-based durability testing indicated the service life of early-production F-35B aircraft is well under the expected 8,000 flight hours, and may be as low as 2,100 flight hours. Fleet F-35B aircraft are expected to start reaching their service-life limit in 2026, based on design usage. The U.S. Air Force followed suit with its first squadron of F-35As in August 2016. In 2018, the F-35 premiered in combat with the Israeli Air Force.The United States plans to buy 2,663 F-35s, which will provide the bulk of the crewed tactical airpower of the U.S. Air Force, Navy, and Marine Corps in coming decades. Deliveries of the F-35 for the U.S. military are scheduled until 2037 with a projected service life up to 2070.Malaysia Airlines Flight 370
Malaysia Airlines Flight 370 (also referred to as MH370, Flight MH370 or MAS370) was a scheduled international passenger flight operated by Malaysia Airlines that disappeared on 8 March 2014 while flying from Kuala Lumpur International Airport, Malaysia, to its destination, Beijing Capital International Airport in China. The crew of the Boeing 777-200ER aircraft last communicated with air traffic control (ATC) around 38 minutes after takeoff when the flight was over the South China Sea. The aircraft was lost from ATC radar screens minutes later, but was tracked by military radar for another hour, deviating westwards from its planned flight path, crossing the Malay Peninsula and Andaman Sea. It left radar range 200 nautical miles (370 km) northwest of Penang Island in northwestern Malaysia. With all 227 passengers and 12 crew aboard presumed dead, the disappearance of Flight 370 was the deadliest incident involving a Boeing 777 and the deadliest in Malaysia Airlines' history, until it was surpassed in both regards by Malaysia Airlines Flight 17 four months later. The combined loss caused significant financial problems for Malaysia Airlines, which was renationalised by the Malaysian government in December 2014.
The search for the missing airplane, which became the most costly in aviation history, focused initially on the South China and Andaman seas, before analysis of the aircraft's automated communications with an Inmarsat satellite identified a possible crash site somewhere in the southern Indian Ocean. The lack of official information in the days immediately after the disappearance prompted fierce criticism from the Chinese public, particularly from relatives of the passengers; most on board Flight 370 were of Chinese origin. Several pieces of marine debris confirmed to be from the aircraft washed ashore in the western Indian Ocean during 2015 and 2016. After a three-year search across 120,000 square kilometres (46,000 sq mi) of ocean failed to locate the aircraft, the Joint Agency Coordination Centre heading the operation suspended their activities in January 2017. A second search launched in January 2018 by the private contractor Ocean Infinity also ended without success after six months.
The disappearance of Flight 370 has been dubbed one of the greatest aviation mysteries of all time. Relying mostly on analysis of data from the Inmarsat satellite with which the aircraft last communicated, the Australian Transport Safety Bureau proposed initially that a hypoxia event was the most likely cause given the available evidence, although there has not been any consensus concerning this theory among investigators. At various stages of the investigation, possible hijacking scenarios were considered, including crew involvement, and suspicion of the airplane's cargo manifest; many unofficial theories have also been proposed by the media. The Malaysian Ministry of Transport's final report from July 2018 was inconclusive, but highlighted Malaysian air traffic controllers' failures to attempt to communicate with the aircraft shortly after its disappearance. In the absence of a definitive cause of the disappearance, safety recommendations and regulations of the air transport industry, citing Flight 370, have been intended mostly to prevent a repetition of the circumstances associated with the loss. These include increased battery life on underwater locator beacons, lengthening of recording times on flight data recorders and cockpit voice recorders, and new standards for aircraft position reporting over open ocean.McDonnell Douglas F-4 Phantom II
The McDonnell Douglas F-4 Phantom II is a tandem two-seat, twin-engine, all-weather, long-range supersonic jet interceptor and fighter-bomber originally developed for the United States Navy by McDonnell Aircraft. It first entered service in 1960 with the U.S. Navy. Proving highly adaptable, it was also adopted by the U.S. Marine Corps and the U.S. Air Force, and by the mid-1960s had become a major part of their air arms.The Phantom is a large fighter with a top speed of over Mach 2.2. It can carry more than 18,000 pounds (8,400 kg) of weapons on nine external hardpoints, including air-to-air missiles, air-to-ground missiles, and various bombs. The F-4, like other interceptors of its time, was designed without an internal cannon. Later models incorporated an M61 Vulcan rotary cannon. Beginning in 1959, it set 15 world records for in-flight performance, including an absolute speed record, and an absolute altitude record.The F-4 was used extensively during the Vietnam War. It served as the principal air superiority fighter for the U.S. Air Force, Navy, and Marine Corps and became important in the ground-attack and aerial reconnaissance roles late in the war. During the Vietnam War, one U.S. Air Force pilot, two weapon systems officers (WSOs), one U.S. Navy pilot and one radar intercept officer (RIO) became aces by achieving five aerial kills against enemy fighter aircraft. The F-4 continued to form a major part of U.S. military air power throughout the 1970s and 1980s, being gradually replaced by more modern aircraft such as the F-15 Eagle and F-16 Fighting Falcon in the U.S. Air Force, the F-14 Tomcat in the U.S. Navy, and the F/A-18 Hornet in the U.S. Navy and U.S. Marine Corps.
The F-4 Phantom II remained in use by the U.S. in the reconnaissance and Wild Weasel (Suppression of Enemy Air Defenses) roles in the 1991 Gulf War, finally leaving service in 1996. It was also the only aircraft used by both U.S. flight demonstration teams: the USAF Thunderbirds (F-4E) and the US Navy Blue Angels (F-4J). The F-4 was also operated by the armed forces of 11 other nations. Israeli Phantoms saw extensive combat in several Arab–Israeli conflicts, while Iran used its large fleet of Phantoms, acquired before the fall of the Shah, in the Iran–Iraq War. Phantom production ran from 1958 to 1981, with a total of 5,195 built, making it the most produced American supersonic military aircraft. As of 2018, 60 years after its first flight, the F-4 remains in service with Iran, Japan, South Korea, Greece, and Turkey. The aircraft has most recently been in service against the Islamic State group in the Middle East.Northrop Grumman B-2 Spirit
The Northrop (later Northrop Grumman) B-2 Spirit, also known as the Stealth Bomber, is an American heavy penetration strategic bomber, featuring low observable stealth technology designed for penetrating dense anti-aircraft defenses; it is a flying wing design with a crew of two. The bomber can deploy both conventional and thermonuclear weapons, such as eighty 500 lb (230 kg)-class (Mk 82) JDAM Global Positioning System-guided bombs, or sixteen 2,400 lb (1,100 kg) B83 nuclear bombs. The B-2 is the only acknowledged aircraft that can carry large air-to-surface standoff weapons in a stealth configuration.
Development started under the "Advanced Technology Bomber" (ATB) project during the Carter administration; its expected performance was one of his reasons for the cancellation of the supersonic B-1A bomber. The ATB project continued during the Reagan administration, but worries about delays in its introduction led to the reinstatement of the B-1 program. Program costs rose throughout development. Designed and manufactured by Northrop, later Northrop Grumman, the cost of each aircraft averaged US$737 million (in 1997 dollars). Total procurement costs averaged $929 million per aircraft, which includes spare parts, equipment, retrofitting, and software support. The total program cost, which included development, engineering and testing, averaged $2.1 billion per aircraft in 1997.Because of its considerable capital and operating costs, the project was controversial in the U.S. Congress. The winding-down of the Cold War in the latter portion of the 1980s dramatically reduced the need for the aircraft, which was designed with the intention of penetrating Soviet airspace and attacking high-value targets. During the late 1980s and 1990s, Congress slashed plans to purchase 132 bombers to 21. In 2008, a B-2 was destroyed in a crash shortly after takeoff, though the crew ejected safely. Twenty B-2s are in service with the United States Air Force, which plans to operate them until 2032.The B-2 is capable of all-altitude attack missions up to 50,000 feet (15,000 m), with a range of more than 6,000 nautical miles (6,900 mi; 11,000 km) on internal fuel and over 10,000 nautical miles (12,000 mi; 19,000 km) with one midair refueling. It entered service in 1997 as the second aircraft designed to have advanced stealth technology after the Lockheed F-117 Nighthawk attack aircraft. Though designed originally as primarily a nuclear bomber, the B-2 was first used in combat dropping conventional, non-nuclear ordnance in the Kosovo War in 1999. It later served in Iraq, Afghanistan, and Libya.Royal Air Force
The Royal Air Force (RAF) is the United Kingdom's aerial warfare force. Formed towards the end of the First World War on 1 April 1918, it is the oldest independent air force in the world. Following victory over the Central Powers in 1918 the RAF emerged as, at the time, the largest air force in the world. Since its formation, the RAF has taken a significant role in British military history. In particular, it played a large part in the Second World War where it fought its most famous campaign, the Battle of Britain.The RAF's mission is to support the objectives of the British Ministry of Defence (MoD), which are to "provide the capabilities needed: to ensure the security and defence of the United Kingdom and overseas territories, including against terrorism; to support the Government’s foreign policy objectives particularly in promoting international peace and security". The RAF describes its mission statement as "... [to provide] An agile, adaptable and capable Air Force that, person for person, is second to none, and that makes a decisive air power contribution in support of the UK Defence Mission". The mission statement is supported by the RAF's definition of air power, which guides its strategy. Air power is defined as "the ability to project power from the air and space to influence the behaviour of people or the course of events".Today the Royal Air Force maintains an operational fleet of various types of aircraft, described by the RAF as being "leading-edge" in terms of technology. This largely consists of fixed-wing aircraft, including: fighter and strike aircraft, airborne early warning and control aircraft, ISTAR and SIGINT aircraft, aerial refueling aircraft and strategic and tactical transport aircraft. The majority of the RAF's rotary-wing aircraft form part of the tri-service Joint Helicopter Command in support of ground forces. Most of the RAF's aircraft and personnel are based in the UK, with many others serving on operations (principally over Iraq and Syria) or at long-established overseas bases (Ascension Island, Cyprus, Gibraltar, and the Falkland Islands). Although the RAF is the principal British air power arm, the Royal Navy's Fleet Air Arm and the British Army's Army Air Corps also deliver air power which is integrated into the maritime, littoral and land environments.Supermarine Spitfire
The Supermarine Spitfire is a British single-seat fighter aircraft used by the Royal Air Force and other Allied countries before, during, and after World War II. Many variants of the Spitfire were built, using several wing configurations, and it was produced in greater numbers than any other British aircraft. It was also the only British fighter produced continuously throughout the war. The Spitfire continues to be popular among enthusiasts; nearly 60 remain airworthy, and many more are static exhibits in aviation museums throughout the world.
The Spitfire was designed as a short-range, high-performance interceptor aircraft by R. J. Mitchell, chief designer at Supermarine Aviation Works, which operated as a subsidiary of Vickers-Armstrong from 1928. Mitchell pushed the Spitfire's distinctive elliptical wing with cutting-edge sunken rivets (designed by Beverley Shenstone) to have the thinnest possible cross-section, helping give the aircraft a higher top speed than several contemporary fighters, including the Hawker Hurricane. Mitchell continued to refine the design until his death in 1937, whereupon his colleague Joseph Smith took over as chief designer, overseeing the Spitfire's development through its multitude of variants.
During the Battle of Britain, from July to October 1940, the public perceived the Spitfire to be the main RAF fighter, though the more numerous Hurricane shouldered a greater proportion of the burden against Nazi Germany's air force, the Luftwaffe. However, Spitfire units had a lower attrition rate and a higher victory-to-loss ratio than those flying Hurricanes because of the Spitfire's higher performance. During the battle, Spitfires were generally tasked with engaging Luftwaffe fighters—mainly Messerschmitt Bf 109E-series aircraft, which were a close match for them.
After the Battle of Britain, the Spitfire superseded the Hurricane to become the backbone of RAF Fighter Command, and saw action in the European, Mediterranean, Pacific, and South-East Asian theatres. Much loved by its pilots, the Spitfire served in several roles, including interceptor, photo-reconnaissance, fighter-bomber, and trainer, and it continued to serve in these roles until the 1950s. The Seafire was a carrier-based adaptation of the Spitfire that served in the Fleet Air Arm from 1942 through to the mid-1950s. Although the original airframe was designed to be powered by a Rolls-Royce Merlin engine producing 1,030 hp (768 kW), it was strong enough and adaptable enough to use increasingly powerful Merlins and, in later marks, Rolls-Royce Griffon engines producing up to 2,340 hp (1,745 kW). As a result, the Spitfire's performance and capabilities improved over the course of its service life.United States Air Force
The United States Air Force (USAF) is the aerial and space warfare service branch of the United States Armed Forces. It is one of the five branches of the United States Armed Forces, and one of the seven American uniformed services. Initially formed as a part of the United States Army on 1 August 1907, the USAF was established as a separate branch of the U.S. Armed Forces on 18 September 1947 with the passing of the National Security Act of 1947. It is the youngest branch of the U.S. Armed Forces, and the fourth in order of precedence. The USAF is the largest and most technologically advanced air force in the world. The Air Force articulates its core missions as air and space superiority, global integrated intelligence, surveillance, and reconnaissance, rapid global mobility, global strike, and command and control.
The U.S. Air Force is a military service branch organized within the Department of the Air Force, one of the three military departments of the Department of Defense. The Air Force, through the Department of the Air Force, is headed by the civilian Secretary of the Air Force, who reports to the Secretary of Defense, and is appointed by the President with Senate confirmation. The highest-ranking military officer in the Air Force is the Chief of Staff of the Air Force, who exercises supervision over Air Force units and serves as one of the Joint Chiefs of Staff. Air Force components are assigned, as directed by the Secretary of Defense, to the combatant commands, and neither the Secretary of the Air Force nor the Chief of Staff of the Air Force have operational command authority over them.
Along with conducting independent air and space operations, the U.S. Air Force provides air support for land and naval forces and aids in the recovery of troops in the field. As of 2017, the service operates more than 5,369 military aircraft, 406 ICBMs and 170 military satellites. It has a $161 billion budget and is the second largest service branch, with 318,415 active duty airmen, 140,169 civilian personnel, 69,200 reserve airmen, and 105,700 Air National Guard airmen.Unmanned aerial vehicle
An unmanned aerial vehicle (UAV), commonly known as a drone, is an aircraft without a human pilot aboard. UAVs are a component of an unmanned aircraft system (UAS); which include a UAV, a ground-based controller, and a system of communications between the two. The flight of UAVs may operate with various degrees of autonomy: either under remote control by a human operator or autonomously by onboard computers.Compared to manned aircraft, UAVs were originally used for missions too "dull, dirty or dangerous" for humans. While they originated mostly in military applications, their use is rapidly expanding to commercial, scientific, recreational, agricultural, and other applications, such as policing, peacekeeping, and surveillance, product deliveries, aerial photography, agriculture, smuggling, and drone racing. Civilian UAVs now vastly outnumber military UAVs, with estimates of over a million sold by 2015.