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Audi

Audi AG is a German automotive manufacturer of luxury vehicles headquartered in Ingolstadt, Bavaria, Germany. A subsidiary of the Volkswagen Group, Audi produces vehicles in nine production facilities worldwide.

The origins of the company are complex, dating back to the early 20th century and the initial enterprises (Horch and the Audiwerke) founded by engineer August Horch (1868–1951). Two other manufacturers (DKW and Wanderer) also contributed to the foundation of Auto Union in 1932. The modern Audi era began in the 1960s, when Auto Union was acquired by Volkswagen from Daimler-Benz. After relaunching the Audi brand with the 1965 introduction of the Audi F103 series, Volkswagen merged Auto Union with NSU Motorenwerke in 1969, thus creating the present-day form of the company.

The company name is based on the Latin translation of the surname of the founder, August Horch. Horch, meaning 'listen', becomes audi in Latin. The four rings of the Audi logo each represent one of four car companies that banded together to create Audi's predecessor company, Auto Union. Audi's slogan is Vorsprung durch Technik, which is translated as 'Progress through Technology'. Audi, along with German brands BMW and Mercedes-Benz, is among the best-selling luxury automobile brands in the world.

Birth of the company and its name
Automobile company Wanderer was originally established in 1885, later becoming a branch of Audi AG. Another company, NSU, which also later merged into Audi, was founded during this time, and later supplied the chassis for Gottlieb Daimler's four-wheeler.

On 14 November 1899, August Horch (1868–1951) established the company A. Horch & Cie. in the Ehrenfeld district of Cologne. In 1902, he moved with his company to Reichenbach im Vogtland. On 10 May 1904, he founded the '''August Horch & Cie. Motorwagenwerke AG''', a joint-stock company in Zwickau (State of Saxony).

After troubles with Horch chief financial officer, August Horch left Motorwagenwerke and founded in Zwickau on 16 July 1909, his second company, the August Horch Automobilwerke GmbH. His former partners sued him for trademark infringement. The German Reichsgericht (Supreme Court) in Leipzig, eventually determined that the Horch brand belonged to his former company.

Since August Horch was prohibited from using horch as a trade name in his new car business, he called a meeting with close business friends, Paul and Franz Fikentscher from Zwickau. At the apartment of Franz Fikentscher, they discussed how to come up with a new name for the company. During this meeting, Franz's son was quietly studying Latin in a corner of the room. Several times he looked like he was on the verge of saying something but would just swallow his words and continue working, until he finally blurted out, "Father – audiatur et altera pars... wouldn't it be a good idea to call it audi instead of horch?". Horch in German means 'hark' or 'hear', which is Audi in the singular imperative form of audire—'to listen'—in Latin. The idea was enthusiastically accepted by everyone attending the meeting. On 25 April 1910 the Audi Automobilwerke GmbH Zwickau (from 1915 on Audiwerke AG Zwickau) was entered in the company's register of Zwickau registration court.

The first Audi automobile, the Audi Type A 10/22 hp Sport-Phaeton, was produced in the same year, followed by the successor Type B 10/28PS in the same year.

Audi started with a 2,612 cc inline-four engine model Type A, followed by a 3,564 cc model, as well as 4,680 cc and 5,720 cc models. These cars were successful even in sporting events. The first six-cylinder model Type M, 4,655 cc appeared in 1924.

August Horch left the Audiwerke in 1920 for a high position at the ministry of transport, but he was still involved with Audi as a member of the board of trustees. In September 1921, Audi became the first German car manufacturer to present a production car, the Audi Type K, with left-handed drive. Left-hand drive spread and established dominance during the 1920s because it provided a better view of oncoming traffic, making overtaking safer when driving on the right.

The merger of the four companies under the logo of four rings
In August 1928, Jørgen Rasmussen, the owner of Dampf-Kraft-Wagen (DKW), acquired the majority of shares in Audiwerke AG. In the same year, Rasmussen bought the remains of the U.S. automobile manufacturer Rickenbacker, including the manufacturing equipment for 8-cylinder engines. These engines were used in Audi Zwickau and Audi Dresden models that were launched in 1929. At the same time, 6-cylinder and 4-cylinder (the "four" with a Peugeot engine) models were manufactured. Audi cars of that era were luxurious cars equipped with special bodywork.

In 1932, Audi merged with Horch, DKW, and Wanderer, to form Auto Union AG, Chemnitz. It was during this period that the company offered the Audi Front that became the first European car to combine a six-cylinder engine with front-wheel drive. It used a power train shared with the Wanderer, but turned 180 degrees, so that the drive shaft faced the front.

Before World War II, Auto Union used the four interlinked rings that make up the Audi badge today, representing these four brands. However, this badge was used only on Auto Union racing cars in that period while the member companies used their own names and emblems. The technological development became more and more concentrated and some Audi models were propelled by Horch- or Wanderer-built engines.

Reflecting the economic pressures of the time, Auto Union concentrated increasingly on smaller cars through the 1930s, so that by 1938 the company's DKW brand accounted for 17.9% of the German car market, while Audi held only 0.1%. After the final few Audis were delivered in 1939 the "Audi" name disappeared completely from the new car market for more than two decades.

World War II
Richard Bruhn, a Nazi party member, was Auto Union’s Chairman of the Board from 1932 to 1945 and then again after the war when the company was reestablished. In 2014 Audi became the last major German car company, after Volkswagen, BMW and Daimler, to commission a study of their wartime activities. The investigation found that the company worked with the SS to build seven labor camps where more than 3,700 prisoners were put to work for Auto Union. In addition, 16,500 more people were forced to work at the company's factories in Zwickau and Chemnitz, and another 18,000 at an underground plant in Bavaria where 4,500 people died.

Some of the company's factories were bombed by the Allies.

Post-World War II
With no prospect of continuing production in Soviet-controlled East Germany, Auto Union executives began the process of relocating what was left of the company to West Germany. A site was chosen in Ingolstadt, Bavaria, to start a spare parts operation in late 1945, which would eventually serve as the headquarters of the reformed Auto Union in 1949.

On 17 August 1948, Auto Union AG of Chemnitz was deleted from the commercial register. These actions had the effect of liquidating Germany's Auto Union AG. The remains of the Audi plant of Zwickau became the VEB (for "People Owned Enterprise") or AWZ (in English: Automobile Works Zwickau).

The former Audi factory in Zwickau restarted assembly of the pre-war models in 1949. These DKW models were renamed to IFA F8 and IFA F9 and were similar to the West German versions. West and East German models were equipped with the traditional and renowned DKW two-stroke engines. The Zwickau plant later manufactured the infamous Trabant until 1991, after it was acquired by the Volkswagen Group following the reunification of Germany, and has since been substantially rebuilt. In 2021, production of the Audi Q4 e-tron began at the plant, marking the return of Audis being manufactured at Zwickau after over 80 years.

New Auto Union unit
A new West German headquartered Auto Union was launched in Ingolstadt with loans from the Bavarian state government and Marshall Plan aid. The reformed company was launched 3 September 1949 and continued DKW's tradition of producing front-wheel drive vehicles with two-stroke engines. This included production of a small but sturdy 125 cc motorcycle and a DKW delivery van, the DKW F89 L at Ingolstadt. The Ingolstadt site was large, consisting of an extensive complex of formerly military buildings which was suitable for administration as well as vehicle warehousing and distribution, but at this stage there was at Ingolstadt no dedicated plant suitable for mass production of automobiles: for manufacturing the company's first post-war mass-market passenger car plant capacity in Düsseldorf was rented from Rheinmetall-Borsig. It was only ten years later, after the company had attracted an investor, when funds became available for construction of major car plant at the Ingolstadt head office site.

In 1958, in response to pressure from Friedrich Flick, then the company's largest single shareholder, Daimler-Benz took an 87% holding in the Auto Union company, and this was increased to a 100% holding in 1959. However, small two-stroke cars were not the focus of Daimler-Benz's interests, and while the early 1960s saw major investment in new Mercedes models and in a state of the art factory for Auto Union's, the company's aging model range at this time did not benefit from the economic boom of the early 1960s to the same extent as competitor manufacturers such as Volkswagen and Opel. The decision to dispose of the Auto Union business was based on its lack of profitability. Ironically, by the time they sold the business, it also included a large new factory and near production-ready modern four-stroke engine, which would enable the Auto Union business, under a new owner, to embark on a period of profitable growth, now producing not Auto Unions or DKWs, but using the "Audi" name, resurrected in 1965 after a 25-year gap.

In 1964, Volkswagen acquired a 50% holding in the business, which included the new factory in Ingolstadt, the DKW and Audi brands along with the rights to the new engine design which had been funded by Daimler-Benz, who in return retained the dormant Horch trademark and the Düsseldorf factory which became a Mercedes-Benz van assembly plant. Eighteen months later, Volkswagen bought complete control of Ingolstadt, and by 1966 were using the spare capacity of the Ingolstadt plant to assemble an additional 60,000 Volkswagen Beetles per year. Two-stroke engines became less popular during the 1960s as customers were more attracted to the smoother four-stroke engines. In September 1965, the DKW F102 was fitted with a four-stroke engine and a facelift for the car's front and rear. Volkswagen dumped the DKW brand because of its associations with two-stroke technology, and having classified the model internally as the F103, sold it simply as the "Audi". Later developments of the model were named after their horsepower ratings and sold as the Audi 60, 75, 80, and Super 90, selling until 1972. Initially, Volkswagen was hostile to the idea of Auto Union as a standalone entity producing its own models having acquired the company merely to boost its own production capacity through the Ingolstadt assembly plant—to the point where Volkswagen executives ordered that the Auto Union name and flags bearing the four rings were removed from the factory buildings. Then VW chief Heinz Nordhoff explicitly forbade Auto Union from any further product development. Fearing that Volkswagen had no long-term ambition for the Audi brand, Auto Union engineers under the leadership of Ludwig Kraus developed the first Audi 100 in secret, without Nordhoff's knowledge. When presented with a finished prototype, Nordhoff was so impressed he authorised the car for production, which when launched in 1968, went on to be a huge success. With this, the resurrection of the Audi brand was now complete, this being followed by the first generation Audi 80 in 1972, which would in turn provide a template for VW's new front-wheel-drive water-cooled range which debuted from the mid-1970s onward.

In 1969, Auto Union merged with NSU, based in Neckarsulm, near Stuttgart. In the 1950s, NSU had been the world's largest manufacturer of motorcycles, but had moved on to produce small cars like the NSU Prinz, the TT and TTS versions of which are still popular as vintage race cars. NSU then focused on new rotary engines based on the ideas of Felix Wankel. In 1967, the new NSU Ro 80 was a car well ahead of its time in technical details such as aerodynamics, light weight, and safety. However, teething problems with the rotary engines put an end to the independence of NSU. The Neckarsulm plant is now used to produce the larger Audi models A6 and A8. The Neckarsulm factory is also home of the "quattro GmbH" (from November 2016 "Audi Sport GmbH"), a subsidiary responsible for development and production of Audi high-performance models: the R8 and the RS model range.

Modern era
The new merged company was incorporated on 1 January 1969 and was known as Audi NSU Auto Union AG, with its headquarters at NSU's Neckarsulm plant, and saw the emergence of Audi as a separate brand for the first time since the pre-war era. Volkswagen introduced the Audi brand to the United States for the 1970 model year. That same year, the mid-sized car that NSU had been working on, the K70, originally intended to slot between the rear-engined Prinz models and the futuristic NSU Ro 80, was instead launched as a Volkswagen.

After the launch of the Audi 100 of 1968, the Audi 80/Fox (which formed the basis for the 1973 Volkswagen Passat) followed in 1972 and the Audi 50 (later rebadged as the Volkswagen Polo) in 1974. The Audi 50 was a seminal design because it was the first incarnation of the Golf/Polo concept, one that led to a hugely successful world car. Ultimately, the Audi 80 and 100 (progenitors of the A4 and A6, respectively) became the company's biggest sellers, whilst little investment was made in the fading NSU range; the Prinz models were dropped in 1973 whilst the fatally flawed NSU Ro80 went out of production in 1977, spelling the effective end of the NSU brand. Production of the Audi 100 had been steadily moved from Ingolstadt to Neckarsulm as the 1970s had progressed, and by the appearance of the second generation C2 version in 1976, all production was now at the former NSU plant. Neckarsulm from that point onward would produce Audi's higher-end models.

The Audi image at this time was a conservative one, and so, a proposal from chassis engineer Jörg Bensinger was accepted to develop the four-wheel drive technology in Volkswagen's Iltis military vehicle for an Audi performance car and rally racing car. The performance car, introduced in 1980, was named the "Audi Quattro", a turbocharged coupé which was also the first German large-scale production vehicle to feature permanent all-wheel drive through a centre differential. Commonly referred to as the "Ur-Quattro" (the "Ur-" prefix is a German augmentative used, in this case, to mean 'original' and is also applied to the first generation of Audi's S4 and S6 Sport Saloons, as in "UrS4" and "UrS6"), few of these vehicles were produced (all hand-built by a single team), but the model was a great success in rallying. Prominent wins proved the viability of all-wheel-drive racecars, and the Audi name became associated with advances in automotive technology.

In 1985, with the Auto Union and NSU brands effectively dead, the company's official name was now shortened to simply Audi AG. At the same time the company's headquarters moved back to Ingolstadt and two new wholly owned subsidiaries; Auto Union GmbH and NSU GmbH, were formed to own and manage the historical trademarks and intellectual property of the original constituent companies (the exception being Horch, which had been retained by Daimler-Benz after the VW takeover), and to operate Audi's heritage operations.

In 1986, as the Passat-based Audi 80 was beginning to develop a kind of "grandfather's car" image, the type 89 was introduced. This completely new development sold extremely well. However, its modern and dynamic exterior belied the low performance of its base engine, and its base package was quite spartan (even the passenger-side mirror was an option). In 1987, Audi put forward a new and very elegant Audi 90, which had a much superior set of standard features. In the early 1990s, sales began to slump for the Audi 80 series, and some basic construction problems started to surface.

Through the early 1990s, Audi began to shift its target market upscale to compete against German automakers Mercedes-Benz and BMW. This began with the release of the Audi V8 in 1990. It was essentially a new engine fitted to the Audi 100/200, but with noticeable bodywork differences. Most obvious was the new grille that was now incorporated in the bonnet.

By 1991, Audi had the four-cylinder Audi 80, the 5-cylinder Audi 90 and Audi 100, the turbocharged Audi 200 and the Audi V8. There was also a coupé version of the 80/90 with both four- and five-cylinder engines.

Although the five-cylinder engine was a successful and robust powerplant, it was still a little too different for the target market. With the introduction of an all-new Audi 100 in 1992, Audi introduced a 2.8L V6 engine. This engine was also fitted to a face-lifted Audi 80 (all 80 and 90 models were now badged 80 except for the USA), giving this model a choice of four-, five-, and six-cylinder engines, in saloon, coupé and convertible body styles.

The five-cylinder was soon dropped as a major engine choice; however, a turbocharged 220 PS version remained. The engine, initially fitted to the 200 quattro 20V of 1991, was a derivative of the engine fitted to the Sport Quattro. It was fitted to the Audi Coupé, named the S2, and also to the Audi 100 body, and named the S4. These two models were the beginning of the mass-produced S series of performance cars.

Audi 5000 unintended acceleration allegations
Sales in the United States fell after a series of recalls from 1982 to 1987 of Audi 5000 models associated with reported incidents of sudden unintended acceleration linked to six deaths and 700 accidents. At the time, NHTSA was investigating 50 car models from 20 manufacturers for sudden surges of power.

A 60 Minutes report aired 23 November 1986, featuring interviews with six people who had sued Audi after reporting unintended acceleration, showing an Audi 5000 ostensibly suffering a problem when the brake pedal was pushed. Subsequent investigation revealed that 60 Minutes had engineered the failure—fitting a canister of compressed air on the passenger-side floor, linked via a hose to a hole drilled into the transmission.

Audi contended, prior to findings by outside investigators, that the problems were caused by driver error, specifically pedal misapplication. Subsequently, the National Highway Traffic Safety Administration (NHTSA) concluded that the majority of unintended acceleration cases, including all the ones that prompted the 60 Minutes report, were caused by driver error such as confusion of pedals. CBS did not acknowledge the test results of involved government agencies, but did acknowledge the similar results of another study.

In a review study published in 2012, NHTSA summarized its past findings about the Audi unintended acceleration problems: "Once an unintended acceleration had begun, in the Audi 5000, due to a failure in the idle-stabilizer system (producing an initial acceleration of 0.3g), pedal misapplication resulting from panic, confusion, or unfamiliarity with the Audi 5000 contributed to the severity of the incident."

This summary is consistent with the conclusions of NHTSA's most technical analysis at the time: "Audi idle-stabilization systems were prone to defects which resulted in excessive idle speeds and brief unanticipated accelerations of up to 0.3g [which is similar in magnitude to an emergency stop in a subway car]. These accelerations could not be the sole cause of [(long-duration) sudden acceleration incidents (SAI)], but might have triggered some SAIs by startling the driver. The defective idle-stabilization system performed a type of electronic throttle control. Significantly: multiple "intermittent malfunctions of the electronic control unit were observed and recorded ... and [were also observed and] reported by Transport Canada."

With a series of recall campaigns, Audi made several modifications; the first adjusted the distance between the brake and accelerator pedal on automatic-transmission models. Later repairs, of 250,000 cars dating back to 1978, added a device requiring the driver to press the brake pedal before shifting out of park. A legacy of the Audi 5000 and other reported cases of sudden unintended acceleration are intricate gear stick patterns and brake interlock mechanisms to prevent inadvertent shifting into forward or reverse. It is unclear how the defects in the idle-stabilization system were addressed.

Audi's U.S. sales, which had reached 74,061 in 1985, dropped to 12,283 in 1991 and remained level for three years, —with resale values falling dramatically. Audi subsequently offered increased warranty protection and renamed the affected models—with the 5000 becoming the 100 and 200 in 1989 —and reached the same sales levels again only by model year 2000.

A 2010 BusinessWeek article—outlining possible parallels between Audi's experience and 2009–2010 Toyota vehicle recalls—noted a class-action lawsuit filed in 1987 by about 7,500 Audi 5000-model owners remains unsettled and remains contested in Chicago's Cook County after appeals at the Illinois state and U.S. federal levels.

Model introductions
In the mid-to-late 1990s, Audi introduced new technologies including the use of aluminium construction. Produced from 1999 to 2005, the Audi A2 was a futuristic super mini, born from the Al2 concept, with many features that helped regain consumer confidence, like the aluminium space frame, which was a first in production car design. In the A2 Audi further expanded their TDI technology through the use of frugal three-cylinder engines. The A2 was extremely aerodynamic and was designed around a wind tunnel. The Audi A2 was criticised for its high price and was never really a sales success but it planted Audi as a cutting-edge manufacturer. The model, a Mercedes-Benz A-Class competitor, sold relatively well in Europe. However, the A2 was discontinued in 2005 and Audi decided not to develop an immediate replacement.

The next major model change came in 1995 when the Audi A4 replaced the Audi 80. The new nomenclature scheme was applied to the Audi 100 to become the Audi A6 (with a minor facelift). This also meant the S4 became the S6 and a new S4 was introduced in the A4 body. The S2 was discontinued. The Audi Cabriolet continued on (based on the Audi 80 platform) until 1999, gaining the engine upgrades along the way. A new A3 hatchback model (sharing the Volkswagen Golf Mk4's platform) was introduced to the range in 1996, and the radical Audi TT coupé and roadster were debuted in 1998 based on the same underpinnings.

The petrol engines available throughout the range were now a 1.4 L, 1.6 L and 1.8 L four-cylinder, 1.8 L four-cylinder turbo, 2.6 L and 2.8 L V6, 2.2 L turbo-charged five-cylinder and the 4.2 L V8 engine. The V6s were replaced by new 2.4 L and 2.8 L 30V V6s in 1998, with marked improvement in power, torque and smoothness. Further engines were added along the way, including a 3.7 L V8 and 6.0 L W12 engine for the A8.

Audi AG today
Audi's sales grew strongly in the 2000s, with deliveries to customers increasing from 653,000 in 2000 to 1,003,000 in 2008. The largest sales increases came from Eastern Europe (+19.3%), Africa (+17.2%) and the Middle East (+58.5%). China in particular has become a key market, representing 108,000 out of 705,000 cars delivered in the first three quarters of 2009. One factor for its popularity in China is that Audis have become the car of choice for purchase by the Chinese government for officials, and purchases by the government are responsible for 20% of its sales in China. As of late 2009, Audi's operating profit of €1.17 billion ($1.85 billion) made it the biggest contributor to parent Volkswagen Group's nine-month operating profit of €1.5 billion, while the other marques in Group such as Bentley and SEAT had suffered considerable losses. May 2011 saw record sales for Audi of America with the new Audi A7 and Audi A3 TDI Clean Diesel. In May 2012, Audi reported a 10% increase in its sales—from 408 units to 480 in the last year alone.

Audi manufactures vehicles in seven plants around the world, some of which are shared with other VW Group marques although many sub-assemblies such as engines and transmissions are manufactured within other Volkswagen Group plants.

Audi's two principal assembly plants in Germany are:
 * Ingolstadt, the former Auto Union site originally opened in 1945 and substantially rebuilt by Daimler-Benz in 1962, and acquired by Volkswagen in 1964 (Q2, A3, A4, A5)
 * Neckarsulm, the former NSU plant, acquired by Volkswagen in 1969: (A4, A5 (cabrio), A6, A7, A8, R8, and all RS variants) - a satellite plant at nearby Böllinger Höfe produces the e-tron GT

Outside of Germany, Audi produces vehicles at:
 * Aurangabad, India, since 2006
 * Bratislava, Slovakia, shared with Volkswagen, SEAT, Škoda and Porsche (Q7 and Q8)
 * Brussels, Belgium, acquired from Volkswagen in 2007 (e-tron)
 * Changchun, China, since 1995
 * Győr, Hungary (TT, A3, Q3)
 * Jakarta, Indonesia, since 2011
 * Martorell, Spain, shared with SEAT and Volkswagen (A1, Q3)
 * San José Chiapa, Mexico (2nd gen Q5)

In September 2012, Audi announced the construction of its first North American manufacturing plant in Puebla, Mexico. This plant became operative in 2016 and produces the second generation Q5.

From 2002 up to 2003, Audi headed the Audi Brand Group, a subdivision of the Volkswagen Group's Automotive Division consisting of Audi, Lamborghini and SEAT, which was focused on sporty values, with the marques' product vehicles and performance being under the higher responsibility of the Audi brand.

In January 2014, Audi, along with the Wireless Power Consortium, operated a booth which demonstrated a phone compartment using the Qi open interface standard at the Consumer Electronics Show (CES). In May, most of the Audi dealers in the UK falsely claimed that the Audi A7, A8, and R8 were Euro NCAP safety tested, all achieving five out of five stars. In fact none were tested.

In 2015, Audi admitted that at least 2.1 million Audi cars had been involved in the Volkswagen emissions testing scandal in which software installed in the cars manipulated emissions data to fool regulators and allow the cars to pollute at higher than government-mandated levels. The A1, A3, A4, A5, A6, TT, Q3 and Q5 models were implicated in the scandal. Audi promised to quickly find a technical solution and upgrade the cars so they can function within emissions regulations. Ulrich Hackenberg, the head of research and development at Audi, was suspended in relation to the scandal. Despite widespread media coverage about the scandal through the month of September, Audi reported that U.S. sales for the month had increased by 16.2%. Audi's parent company Volkswagen announced on 18 June 2018 that Audi chief executive Rupert Stadler had been arrested.

In November 2015, the U.S. Environmental Protection Agency implicated the 3-liter diesel engine versions of the 2016 Audi A6 Quattro, A7 Quattro, A8, A8L and the Q5 as further models that had emissions regulation defeat-device software installed. Thus, these models emitted nitrogen oxide at up to nine times the legal limit when the car detected that it was not hooked up to emissions testing equipment.

In November 2016, Audi expressed an intention to establish an assembly factory in Pakistan, with the company's local partner acquiring land for a plant in Korangi Creek Industrial Park in Karachi. Approval of the plan would lead to an investment of $30 million in the new plant. Audi planned to cut 9,500 jobs in Germany starting from 2020 till 2025 to fund electric vehicles and digital working.

In February 2020, Volkswagen AG announced that it plans to take over all Audi shares it does not own (totalling 0.36%) via a squeeze-out according to German stock corporation law, thus making Audi a fully owned subsidiary of the Volkswagen Group. This change took effect from 16 November 2020, when Audi became a wholly owned subsidiary of the Volkswagen Group.

In January 2021, Audi announced that it is planning to sell 1 million vehicles in China in 2023, comparing to 726,000 vehicles in 2020.

Audi AI
Audi AI is a driver assist feature offered by Audi. The company's stated intent is to offer fully autonomous driving at a future time, acknowledging that legal, regulatory and technical hurdles must be overcome to achieve this goal. On 4 June 2017, Audi stated that its new A8 will be fully self-driving for speeds up to 60 km/h using its Audi AI. Contrary to other cars, the driver will not have to do safety checks such as touching the steering wheel every 15 seconds to use this feature. The Audi A8 will therefore be the first production car to reach level 3 autonomous driving, meaning that the driver can safely turn their attention away from driving tasks, e.g. the driver can text or watch a movie. Audi will also be the first manufacturer to use a 3D Lidar system in addition to cameras and ultrasonic sensors for their AI.

Bodyshells
Audi produces 100% galvanised cars to prevent corrosion, and was the first mass-market vehicle to do so, following introduction of the process by Porsche, c. 1975. Along with other precautionary measures, the full-body zinc coating has proved to be very effective in preventing rust. The body's resulting durability even surpassed Audi's own expectations, causing the manufacturer to extend its original 10-year warranty against corrosion perforation to currently 12 years (except for aluminium bodies which do not rust).

Space Frame

Audi introduced a new series of vehicles in the mid-1990s and continues to pursue new technology and high performance. An all-aluminium car was brought forward by Audi, and in 1994 the Audi A8 was launched, which introduced aluminium space frame technology (called Audi Space Frame or ASF) which saves weight and improves torsion rigidity compared to a conventional steel frame. Prior to that effort, Audi used examples of the Type 44 chassis fabricated out of aluminium as test-beds for the technique. The disadvantage of the aluminium frame is that it is very expensive to repair and requires a specialized aluminium bodyshop. The weight reduction is somewhat offset by the quattro four-wheel drive system which is standard in most markets. Nonetheless, the A8 is usually the lightest all-wheel drive car in the full-size luxury segment, also having best-in-class fuel economy. The Audi A2, Audi TT and Audi R8 also use Audi Space Frame designs.

Layout
For most of its lineup (excluding the A3, A1, and TT models), Audi has not adopted the transverse engine layout which is typically found in economy cars (such as Peugeot and Citroën), since that would limit the type and power of engines that can be installed. To be able to mount powerful engines (such as a V8 engine in the Audi S4 and Audi RS4, as well as the W12 engine in the Audi A8L W12), Audi has usually engineered its more expensive cars with a longitudinally front-mounted engine, in an "overhung" position, over the front wheels in front of the axle line—this layout dates back to the DKW and Auto Union saloons from the 1950s. But while this allows for the easy adoption of all-wheel drive, it goes against the ideal 50:50 weight distribution.

In all its post Volkswagen era models, Audi has firmly refused to adopt the traditional rear-wheel drive layout favored by its two archrivals Mercedes-Benz and BMW, favoring either front-wheel drive or all-wheel drive. The majority of Audi's lineup in the United States features all-wheel drive standard on most of its expensive vehicles (only the entry-level trims of the A4 and A6 are available with front-wheel drive), in contrast to Mercedes-Benz and BMW whose lineup treats all-wheel drive as an option. BMW did not offer all-wheel drive on its V8-powered cars (as opposed to crossover SUVs) until the 2010 BMW 7 Series and 2011 BMW 5 Series, while the Audi A8 has had all-wheel drive available/standard since the 1990s. Regarding high-performance variants, Audi S and RS models have always had all-wheel drive, unlike their direct rivals from BMW M and Mercedes-AMG whose cars are rear-wheel drive only (although their performance crossover SUVs are all-wheel drive).

Audi has recently applied the quattro badge to models such as the A3 and TT which do not use the Torsen-based system as in prior years with a mechanical center differential, but with the Haldex Traction electro-mechanical clutch AWD system.

Engines

Prior to the introduction of the Audi 80 and Audi 50 in 1972 and 1974, respectively, Audi had led the development of the EA111 and EA827 inline-four engine families. These new power units underpinned the water-cooled revival of parent company Volkswagen (in the Polo, Golf, Passat and Scirocco), whilst the many derivatives and descendants of these two basic engine designs have appeared in every generation of VW Group vehicles right up to the present day.

In the 1980s, Audi, along with Volvo, was the champion of the inline-five cylinder, 2.1/2.2 L engine as a longer-lasting alternative to more traditional six-cylinder engines. This engine was used not only in production cars but also in their race cars. The 2.1 L inline five-cylinder engine was used as a base for the rally cars in the 1980s, providing well over 400 hp after modification. Before 1990, there were engines produced with a displacement between 2.0 L and 2.3 L. This range of engine capacity allowed for both fuel economy and power.

For the ultra-luxury version of its Audi A8 fullsize luxury flagship sedan, the Audi A8L W12, Audi uses the Volkswagen Group W12 engine instead of the conventional V12 engine favored by rivals Mercedes-Benz and BMW. The W12 engine configuration (also known as a "WR12") is created by forming two imaginary narrow-angle 15° VR6 engines at an angle of 72°, and the narrow angle of each set of cylinders allows just two overhead camshafts to drive each pair of banks, so just four are needed in total. The advantage of the W12 engine is its compact packaging, allowing Audi to build a 12-cylinder sedan with all-wheel drive, whereas a conventional V12 engine could have only a rear-wheel drive configuration as it would have no space in the engine bay for a differential and other components required to power the front wheels. In fact, the 6.0 L W12 in the Audi A8L W12 is smaller in overall dimensions than the 4.2 L V8 that powers the Audi A8 4.2 variants. The 2011 Audi A8 debuted a revised 6.3-litre version of the W12 (WR12) engine with 500 PS.

Fuel Stratified Injection
New models of the A3, A4, A6 and A8 have been introduced, with the ageing 1.8-litre engine now having been replaced by new Fuel Stratified Injection (FSI) engines. Nearly every petroleum burning model in the range now incorporates this fuel-saving technology.

Direct-Shift Gearbox
In 2003, Volkswagen introduced the Direct-Shift Gearbox (DSG), a type of dual-clutch transmission. It is a type of automatic transmission, drivable like a conventional torque converter automatic transmission. Based on the gearbox found in the Group B S1, the system includes dual electro-hydraulically controlled clutches instead of a torque converter. This is implemented in some VW Golfs, Audi A3, Audi A4 and TT models where DSG is called S-Tronic.

LED daytime running lights
Beginning in 2005, Audi has implemented white LED technology as daytime running lights (DRL) in their products. The distinctive shape of the DRLs has become a trademark of sorts. LEDs were first introduced on the Audi A8 W12, the world's first production car to have LED DRLs,  and have since spread throughout the entire model range. The LEDs are present on some Audi billboards.

Since 2010, Audi has also offered the LED technology in low- and high-beam headlights.

Multi Media Interface
Starting with the 2003 Audi A8, Audi has used a centralised control interface for its on-board infotainment systems, called Multi Media Interface (MMI). It is essentially a rotating control knob and 'segment' buttons—designed to control all in-car entertainment devices (radio, CD changer, iPod, TV tuner), satellite navigation, heating and ventilation, and other car controls with a screen.

The availability of MMI has gradually filtered down the Audi lineup, and following its introduction on the third generation A3 in 2011, MMI is now available across the entire range. It has been generally well received, as it requires less menu-surfing with its segment buttons around a central knob, along with 'main function' direct access buttons—with shortcuts to the radio or phone functions. The colour screen is mounted on the upright dashboard, and on the A4 (new), A5, A6, A8, and Q7, the controls are mounted horizontally.

Synthetic fuels
Audi has assisted with technology to produce synthetic diesel from water and carbon dioxide. Audi calls the synthetic diesel E-diesel. It is also working on synthetic gasoline (which it calls E-gasoline).

Logistics
Audi uses scanning gloves for parts registration during assembly, and automatic robots to transfer cars from factory to rail cars.

Current model range
The following tables list Audi production vehicles that are sold as of 2024:

Electric vehicles
Audi is planning an alliance with the Japanese electronics giant Sanyo to develop a pilot hybrid electric project for the Volkswagen Group. The alliance could result in Sanyo batteries and other electronic components being used in future models of the Volkswagen Group. Concept electric vehicles unveiled to date include the Audi A1 Sportback Concept, Audi A4 TDI Concept E, and the fully electric Audi e-tron Concept Supercar.

Self-driving cars
In December 2018, Audi announced to invest 14 billion Euro ($15.9 billion) in e-mobility, self-driving cars.

Production figures

 * Data from 1998 to 2010. Figures for different body types/versions of models have been merged to create overall figures for each model.

Motorsport
Audi has competed in various forms of motorsports. Audi's tradition in motorsport began with their former company Auto Union in the 1930s. In the 1990s, Audi found success in the Touring and Super Touring categories of motor racing after success in circuit racing in North America.

Rallying
In 1980, Audi released the Quattro, a four-wheel drive (4WD) turbocharged car that went on to win rallies and races worldwide. It is considered one of the most significant rally cars of all time, because it was one of the first to take advantage of the then-recently changed rules which allowed the use of four-wheel drive in competition racing. Many critics doubted the viability of four-wheel drive racers, thinking them to be too heavy and complex, yet the Quattro was to become a successful car. It led its first rally before going off the road, however, the rally world had been served notice 4WD was the future. The Quattro went on to achieve much success in the World Rally Championship. It won the 1983 (Hannu Mikkola) and the 1984 (Stig Blomqvist) drivers' titles, and brought Audi the manufacturers' title in 1982 and 1984.

In 1984, Audi launched the short-wheelbase Sport Quattro which dominated rally races in Monte Carlo and Sweden, with Audi taking all podium places, but succumbed to problems further into WRC contention. In 1985, after another season mired in mediocre finishes, Walter Röhrl finished the season in his Sport Quattro S1, and helped place Audi second in the manufacturers' points. Audi also received rally honours in the Hong Kong to Beijing rally in that same year. Michèle Mouton, the only female driver to win a round of the World Rally Championship and a driver for Audi, took the Sport Quattro S1, now simply called the "S1", and raced in the Pikes Peak International Hill Climb. The 1439 m climb race pits a driver and car to drive to the summit of the 4302 m Pikes Peak mountain in Colorado, and in 1985, Michèle Mouton set a new record of 11:25.39, and being the first woman to set a Pikes Peak record. In 1986, Audi formally left international rallying following an accident in Portugal involving driver Joaquim Santos in his Ford RS200. Santos swerved to avoid hitting spectators in the road, and left the track into the crowd of spectators on the side, killing three and injuring 30. Bobby Unser used an Audi in that same year to claim a new record for the Pikes Peak Hill Climb at 11:09.22.

In 1987, Walter Röhrl claimed the title for Audi setting a new Pikes Peak International Hill Climb record of 10:47.85 in his Audi S1, which he had retired from the WRC two years earlier. The Audi S1 employed Audi's time-tested inline-five-cylinder turbocharged engine, with the final version generating 441 kW. The engine was mated to a six-speed gearbox and ran on Audi's famous four-wheel drive system. All of Audi's top drivers drove this car; Hannu Mikkola, Stig Blomqvist, Walter Röhrl and Michèle Mouton. This Audi S1 started the range of Audi 'S' cars, which now represents an increased level of sports-performance equipment within the mainstream Audi model range.

In the United States
As Audi moved away from rallying and into circuit racing, they chose to move first into America with the Trans-Am in 1988.

In 1989, Audi moved to International Motor Sports Association (IMSA) GTO with the Audi 90, however as they avoided the two major endurance events (Daytona and Sebring) despite winning on a regular basis, they would lose out on the title.

Touring cars
In 1990, having completed their objective to market cars in North America, Audi returned to Europe, turning first to the Deutsche Tourenwagen Meisterschaft (DTM) series with the Audi V8, and then in 1993, being unwilling to build cars for the new formula, they turned their attention to the fast-growing Super Touring series, which are a series of national championships. Audi first entered in the French Supertourisme and Italian Superturismo. In the following year, Audi would switch to the German Super Tourenwagen Cup (known as STW), and then to British Touring Car Championship (BTCC) the year after that.

The Fédération Internationale de l'Automobile (FIA), having difficulty regulating the quattro four-wheel drive system, and the impact it had on the competitors, would eventually ban all four-wheel drive cars from competing in the series in 1998, but by then, Audi switched all their works efforts to sports car racing.

By 2000, Audi would still compete in the US with their RS4 for the SCCA Speed World GT Challenge, through dealer/team Champion Racing competing against Corvettes, Vipers, and smaller BMWs (where it is one of the few series to permit 4WD cars). In 2003, Champion Racing entered an RS6. Once again, the quattro four-wheel drive was superior, and Champion Audi won the championship. They returned in 2004 to defend their title, but a newcomer, Cadillac with the new Omega Chassis CTS-V, gave them a run for their money. After four victories in a row, the Audis were sanctioned with several negative changes that deeply affected the car's performance. Namely, added ballast weights, and Champion Audi deciding to go with different tyres, and reducing the boost pressure of the turbocharger.

In 2004, after years of competing with the TT-R in the revitalised DTM series, with privateer team Abt Racing/Christian Abt taking the 2002 title with Laurent Aïello, Audi returned as a full factory effort to touring car racing by entering two factory-supported Joest Racing A4 DTM cars.

24 Hours of Le Mans
Audi began racing prototype sportscars in 1999, debuting at the Le Mans 24 hour. Two car concepts were developed and raced in their first season - the Audi R8R (open-cockpit 'roadster' prototype) and the Audi R8C (closed-cockpit 'coupé' GT-prototype). The R8R scored a credible podium on its racing debut at Le Mans and was the concept which Audi continued to develop into the 2000 season due to favourable rules for open-cockpit prototypes.

However, most of the competitors (such as BMW, Toyota, Mercedes and Nissan) retired at the end of 1999. The factory-supported Joest Racing team won at Le Mans three times in a row with the Audi R8 (2000–2002), as well as winning every race in the American Le Mans Series in its first year. Audi also sold the car to customer teams such as Champion Racing.

In 2003, two Bentley Speed 8s, with engines designed by Audi, and driven by Joest drivers loaned to the fellow Volkswagen Group company, competed in the GTP class, and finished the race in the top two positions, while the Champion Racing R8 finished third overall, and first in the LMP900 class. Audi returned to the winner's podium at the 2004 race, with the top three finishers all driving R8s: Audi Sport Japan Team Goh finished first, Audi Sport UK Veloqx second, and Champion Racing third.

At the 2005 24 Hours of Le Mans, Champion Racing entered two R8s, along with an R8 from the Audi PlayStation Team Oreca. The R8s (which were built to old LMP900 regulations) received a narrower air inlet restrictor, reducing power, and an additional 50 kg of weight compared to the newer LMP1 chassis. On average, the R8s were about 2–3 seconds off pace compared to the Pescarolo–Judd. But with a team of excellent drivers and experience, both Champion R8s were able to take first and third, while the Oreca team took fourth. The Champion team was also the first American team to win Le Mans since the Gulf Ford GTs in 1967. This also ends the long era of the R8; however, its replacement for 2006, called the Audi R10 TDI, was unveiled on 13 December 2005.

The R10 TDI employed many new and innovative features, the most notable being the twin-turbocharged direct injection diesel engine. It was first raced in the 2006 12 Hours of Sebring as a race-test in preparation for the 2006 24 Hours of Le Mans, which it later went on to win. Audi had a win in the first diesel sports car at 12 Hours of Sebring (the car was developed with a Diesel engine due to ACO regulations that favor diesel engines). As well as winning the 24 Hours of Le Mans in 2006, the R10 TDI beat the Peugeot 908 HDi FAP in, and in , (however Peugeot won the 24h in 2009) with a podium clean-sweep (all four 908 entries retired) while breaking a distance record (set by the Porsche 917K of Martini Racing in ), in with the R15 TDI Plus.

Audi's sports car racing success would continue with the Audi R18's victory at the 2011 24 Hours of Le Mans. Audi Sport Team Joest's Benoît Tréluyer earned Audi their first pole position in five years while the team's sister car locked out the front row. Early accidents eliminated two of Audi's three entries, but the sole remaining Audi R18 TDI of Tréluyer, Marcel Fässler, and André Lotterer held off the trio of Peugeot 908s to claim victory by a margin of 13.8 seconds.

American Le Mans Series
Audi entered a factory racing team run by Joest Racing into the American Le Mans Series under the Audi Sport North America name in 2000. This was a successful operation with the team winning on its debut in the series at the 2000 12 Hours of Sebring. Factory-backed Audi R8s were the dominant car in ALMS taking 25 victories between 2000 and the end of the 2002 season. In 2003, Audi sold customer cars to Champion Racing as well as continuing to race the factory Audi Sport North America team. Champion Racing won many races as a private team running Audi R8s and eventually replaced Team Joest as the Audi Sport North America between 2006 and 2008. Since 2009 Audi has not taken part in full American Le Mans Series Championships, but has competed in the series opening races at Sebring, using the 12-hour race as a test for Le Mans, and also as part of the 2012 FIA World Endurance Championship season calendar.

European Le Mans Series
Audi participated in the 2003 1000km of Le Mans which was a one-off sports car race in preparation for the 2004 European Le Mans Series. The factory team Audi Sport UK won races and the championship in the 2004 season but Audi was unable to match their sweeping success of Audi Sport North America in the American Le Mans Series, partly due to the arrival of a factory competitor in LMP1, Peugeot. The French manufacturer's 908 HDi FAP became the car to beat in the series from 2008 onwards with 20 LMP wins. However, Audi were able to secure the championship in 2008 even though Peugeot scored more race victories in the season.

2012
In 2012, the FIA sanctioned a World Endurance Championship which would be organised by the ACO as a continuation of the ILMC. Audi competed won the first WEC race at Sebring and followed this up with a further three successive wins, including the 2012 24 Hours of Le Mans. Audi scored a final 5th victory in the 2012 WEC in Bahrain and were able to win the inaugural WEC Manufacturers' Championship.

2013
As defending champions, Audi once again entered the Audi R18 e-tron quattro chassis into the 2013 WEC and the team won the first five consecutive races, including the 2013 24 Hours of Le Mans. The victory at Round 5, Circuit of the Americas, was of particular significance as it marked the 100th win for Audi in Le Mans prototypes. Audi secured their second consecutive WEC Manufacturers' Championship at Round 6 after taking second place and half points in the red-flagged Fuji race.

2014
For the 2014 season, Audi entered a redesigned and upgraded R18 e-tron quattro which featured a 2 MJ energy recovery system. As defending champions, Audi would once again face a challenge in LMP1 from Toyota, and additionally from Porsche who returned to endurance racing after a 16-year absence. The season-opening 6hrs of Silverstone was a disaster for Audi who saw both cars retire from the race, marking the first time that an Audi car has failed to score a podium in a World Endurance Championship race. The team won two races and finished second in the manufacturers' championship.

2015
Audi won the first two races of the season, but thereafter failed to win again, finishing second in the manufacturers' championship.

2016
For the third year in a row, Audi won two races and finished second in the manufacturers' championship. Audi had left WEC after the 2016 season.

Formula E
Audi provided factory support to Abt Sportsline in the FIA Formula E Championship, The team competed under the title of Audi Sport Abt Formula E Team in the inaugural 2014-15 Formula E season. On 13 February 2014 the team announced its driver line up as Daniel Abt and World Endurance Championship driver Lucas di Grassi.

Audi had left Formula E after the 2020-21 Formula E season.

Formula One
Audi has been linked to Formula One in recent years but has always resisted due to the company's opinion that it is not relevant to road cars, but hybrid power unit technology has been adopted into the sport, swaying the company's view and encouraging research into the program by former Ferrari team principal Stefano Domenicali.

Audi announced in August 2022 that it would enter the Championship as an engine manufacturer in. In October, Audi confirmed its partnership with Sauber Motorsport for the year 2026, acquiring a stake in the company for the German brand to enter the competition by renaming the team and supplying engines.

On 26 April 2024, it was announced that Nico Hülkenberg will take up the seat at Sauber for 2025, on a multi-year contract, meaning that Hülkenberg is the first confirmed Audi driver in Formula One in 2026.

Current factory drivers
• 🇮🇹 Mattia Drudi

• 🇩🇪 Luca Engstler

• Ricardo Feller

• 🇫🇷 Simon Gachet

• 🇩🇪 Christopher Haase

• 🇦🇹 Max Hofer

• 🇩🇪 Pierre Kaffer

• 🇧🇪 Gilles Magnus

• 🇩🇪 Dennis Marschall

• 🇩🇪 Christopher Mies

•  Patric Niederhauser

• 🇩🇪 Frank Stippler

• 🇧🇪 Frédéric Vervisch

• 🇩🇪 Markus Winkelhock

Branding
The Audi emblem is four overlapping rings that represent the four marques of Auto Union. The Audi emblem symbolises the amalgamation of Audi with DKW, Horch and Wanderer: the first ring from the left represents Audi, the second represents DKW, third is Horch, and the fourth and last ring Wanderer. The design is popularly believed to have been the idea of Klaus von Oertzen, the director of sales at Wanderer—when Berlin was chosen as the host city for the 1936 Summer Olympics and that a form of the Olympic logo symbolized the newly established Auto Union's desire to succeed. Somewhat ironically, the International Olympic Committee later sued Audi in the International Trademark Court in 1995, where they lost.

The original "Audi" script, with the distinctive slanted tails on the "A" and "d" was created for the historic Audi company in 1920 by the famous graphic designer Lucian Bernhard, and was resurrected when Volkswagen revived the brand in 1965. Following the demise of NSU in 1977, less prominence was given to the four rings, in preference to the "Audi" script encased within a black (later red) ellipse, and was commonly displayed next to the Volkswagen roundel when the two brands shared a dealer network under the V.A.G banner. The ellipse (known as the Audi Oval) was phased out after 1994, when Audi formed its own independent dealer network, and prominence was given back to the four rings—at the same time Audi Sans (a derivative of Univers) was adopted as the font for all marketing materials, corporate communications and was also used in the vehicles themselves.

As part of Audi's centennial celebration in 2009, the company updated the logo, changing the font to left-aligned Audi Type, and altering the shading for the overlapping rings. The revised logo was designed by Rayan Abdullah.

Audi developed a Corporate Sound concept, with Audi Sound Studio designed for producing the Corporate Sound. The Corporate Sound project began with sound agency Klangerfinder GmbH & Co KG and s12 GmbH. Audio samples were created in Klangerfinder's sound studio in Stuttgart, becoming part of Audi Sound Studio collection. Other Audi Sound Studio components include The Brand Music Pool, The Brand Voice. Audi also developed Sound Branding Toolkit including certain instruments, sound themes, rhythm and car sounds which all are supposed to reflect the AUDI sound character.

Audi started using a beating heart sound trademark beginning in 1996. An updated heartbeat sound logo, developed by agencies KLANGERFINDER GmbH & Co KG of Stuttgart and S12 GmbH of Munich, was first used in 2010 in an Audi A8 commercial with the slogan The Art of Progress.

Slogans
Audi's corporate tagline is Vorsprung durch Technik, meaning 'Progress through Technology'. The German-language tagline is used in many European countries, including the United Kingdom (but not in Italy, where All'avanguardia della tecnica is used), and in other markets, such as Latin America, Oceania, Africa and parts of Asia including Japan. Originally, the American tagline was Innovation through technology, but in Canada Vorsprung durch Technik was used. Since 2007, Audi has used the slogan Truth in Engineering in the U.S. However, since the Audi emissions testing scandal came to light in September 2015, this slogan was lambasted for being discordant with reality. In fact, just hours after disgraced Volkswagen CEO Martin Winterkorn admitted to cheating on emissions data, an advertisement during the 2015 Primetime Emmy Awards promoted Audi's latest advances in low emissions technology with Kermit the Frog stating, "It's not that easy being green."

Vorsprung durch Technik was first used in English-language advertising after Sir John Hegarty of the Bartle Bogle Hegarty advertising agency visited the Audi factory in 1982. In the original British television commercials, the phrase was voiced by Geoffrey Palmer. After its repeated use in advertising campaigns, the phrase found its way into popular culture, including the British comedy Only Fools and Horses, the U2 song "Zooropa" and the Blur song "Parklife". Similar-sounding phrases have also been used, including as the punchline for a joke in the movie Lock, Stock and Two Smoking Barrels and in the British TV series Peep Show.

Typography
Audi Sans (based on Univers Extended) was originally created in 1997 by Ole Schäfer for MetaDesign. MetaDesign was later commissioned for a new corporate typeface called Audi Type, designed by Paul van der Laan and Pieter van Rosmalen of Bold Monday. The font began to appear in Audi's 2009 products and marketing materials.

Sponsorships
Audi is a strong partner of different kinds of sports. In football, long partnerships exist between Audi and domestic clubs including Bayern Munich, Hamburger SV, 1. FC Nürnberg, Hertha BSC, and Borussia Mönchengladbach and international clubs including Chelsea, Real Madrid, FC Barcelona, A.C. Milan, AFC Ajax and Perspolis. Audi also sponsors winter sports: The Audi FIS Alpine Ski World Cup is named after the company. Additionally, Audi supports the German Ski Association (DSV) as well as the alpine skiing national teams of Switzerland, Sweden, Finland, France, Liechtenstein, Italy, Austria and the U.S. For almost two decades, Audi fosters golf sport: for example with the Audi quattro Cup and the HypoVereinsbank Ladies German Open presented by Audi. In sailing, Audi is engaged in the Medcup regatta and supports the team Luna Rossa during the Louis Vuitton Pacific Series and also is the primary sponsor of the Melges 20 sailboat. Further, Audi sponsors the regional teams ERC Ingolstadt (hockey) and FC Ingolstadt 04 (soccer). In 2009, the year of Audi's 100th anniversary, the company organized the Audi Cup for the first time. Audi also sponsor the New York Yankees as well. In October 2010 they agreed to a three sponsorship year-deal with Everton. Audi also sponsors the England Polo Team and holds the Audi Polo Awards.

Marvel Cinematic Universe
Since the start of the Marvel Cinematic Universe, Audi signed a deal to sponsor, promote and provide vehicles for several films. So far these have been, Iron Man, Iron Man 2, Iron Man 3, Avengers: Age of Ultron, Captain America: Civil War, Spider-Man: Homecoming, Avengers: Endgame and Spider-Man: Far From Home. The R8 supercar became the personal vehicle for Tony Stark (played by Robert Downey Jr.) for six of these films. The e-tron vehicles were promoted in Endgame and Far From Home. Several commercials were co-produced by Marvel and Audi to promote several new concepts and some of the latest vehicles such as the A8, SQ7 and the e-Tron fleet.

Multitronic campaign

In 2001, Audi promoted the new multitronic continuously variable transmission with television commercials throughout Europe, featuring an impersonator of musician and actor Elvis Presley. A prototypical dashboard figure—later named "Wackel-Elvis" ("Wobble Elvis" or "Wobbly Elvis")—appeared in the commercials to demonstrate the smooth ride in an Audi equipped with the multitronic transmission. The dashboard figure was originally intended for use in the commercials only, but after they aired the demand for Wackel-Elvis fans grew among fans and the figure was mass-produced in China and marketed by Audi in their factory outlet store.

Audi TDI
As part of Audi's attempt to promote its Diesel technology in 2009, the company began Audi Mileage Marathon. The driving tour featured a fleet of 23 Audi TDI vehicles from 4 models (Audi Q7 3.0 TDI, Audi Q5 3.0 TDI, Audi A4 3.0 TDI, Audi A3 Sportback 2.0 TDI with S tronic transmission) travelling across the American continent from New York to Los Angeles, passing major cities like Chicago, Dallas and Las Vegas during the 13 daily stages, as well as natural wonders including the Rocky Mountains, Death Valley and the Grand Canyon.

Audi e-tron
The next phase of technology Audi is developing is the e-tron electric drive powertrain system. They have shown several concept cars, each with different levels of size and performance. The original e-tron concept shown at the 2009 Frankfurt motor show is based on the platform of the R8 and has been scheduled for limited production. Power is provided by electric motors at all four wheels. The second concept was shown at the 2010 Detroit Motor Show. Power is provided by two electric motors at the rear axle. This concept is also considered to be the direction for a future mid-engined gas-powered 2-seat performance coupe. The Audi A1 e-tron concept, based on the Audi A1 production model, is a hybrid vehicle with a range extending Wankel rotary engine to provide power after the initial charge of the battery is depleted. It is the only concept of the three to have range-extending capability. The car is powered through the front wheels, always using electric power.

It is all set to be displayed at the Auto Expo 2012 in New Delhi, India, from 5 January. It is powered by a 1.4 litre engine, and can cover a distance up to 54 km on a single charge. The e-tron was also shown in the 2013 blockbuster film Iron Man 3 and was driven by Tony Stark (Iron Man).

Lawsuit on the use of the letter Q
In early 2005, Nissan North America Inc. filed a lawsuit against Audi over the use of the letter "Q" as a model name.

Audi is using the "Q" for the designation of their quattro four-wheel drive system, used in production cars for over twenty-five years (Audi's Quattro trademark is actually an umbrella term for several types of four-wheel-drive systems developed by Torsen, Haldex Traction AB, and Borg-Warner, the latter being used in the Q7). Nissan's Infiniti marque first used Q for their 1989 Infiniti Q45 flagship, but later expanded to its entire lineup, with Q for passenger cars (the Q30, Q40, Q50, and Q60) and QX for SUVs (the QX30, QX50, QX60, and QX70).

A settlement between Audi AG and Nissan was reached in late 2006. The agreement stipulates that Audi will only use the Q-prefix for three models, the Q3, Q5 and the Q7. Audi has since released other Q series cars as well, such as the Q2, Q6, and Q8.

In video games
Audi has supported the European version of PlayStation Home, the PlayStation 3's online community-based service, by releasing a dedicated Home space. Audi is the first carmaker to develop such a space for Home. On 17 December 2009, Audi released two spaces; the Audi Home Terminal and the Audi Vertical Run. The Audi Home Terminal features an Audi TV channel delivering video content, an Internet Browser feature, and a view of a city. The Audi Vertical Run is where users can access the mini-game Vertical Run, a futuristic mini-game featuring Audi's e-tron concept. Players collect energy and race for the highest possible speeds and the fastest players earn a place in the Audi apartments located in a large tower in the centre of the Audi Space. In both the Home Terminal and Vertical Run spaces, there are teleports where users can teleport back and forth between the two spaces. Audi had stated that additional content would be added in 2010. On 31 March 2015 Sony shutdown the PlayStation Home service rendering all content for it inaccessible.

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Aircraft

An aircraft (: aircraft) is a vehicle that is able to fly by gaining support from the air. It counters the force of gravity by using either static lift or the dynamic lift of an airfoil, or, in a few cases, direct downward thrust from its engines. Common examples of aircraft include airplanes, helicopters, airships (including blimps), gliders, paramotors, 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, whereas 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 (if any), usage and others.

History
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:
 * Pioneers of flight, from the earliest experiments to 1914.
 * First World War, 1914 to 1918.
 * Aviation between the World Wars, 1918 to 1939.
 * Second World War, 1939 to 1945.
 * Postwar era, also called the Jet Age, 1945 to the present day.

Lighter than air – aerostats

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 cells 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 World War II, 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 – aerodynes
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. 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 Lockheed Martin 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.

Fixed-wing
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.

The first heavier-than-air craft capable of controlled free-flight were gliders. A glider designed by George Cayley carried out the first true manned, controlled flight in 1853. The first powered and controllable fixed-wing aircraft (the airplane or aeroplane) was invented by Wilbur and Orville Wright.

Besides the method of propulsion (if any), fixed-wing aircraft are in general characterized by their wing configuration. The most important wing characteristics are:
 * Number of wings — Monoplane, biplane, triplane, or multiplane.
 * Wing support — Braced or cantilever, rigid or flexible.
 * Wing planform — including aspect ratio, angle of sweep, and any variations along the span (including the important class of delta wings).
 * Location of the horizontal stabilizer, if any.
 * Dihedral angle — positive, zero, or negative (anhedral).

A variable geometry aircraft can change its wing configuration during flight.

A flying wing has no fuselage, though it may have small blisters or pods. The opposite of this is a lifting body, which has no wings, though it may have small stabilizing and control surfaces.

Wing-in-ground-effect vehicles are generally 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 minimal pilot power, but this is only because they are so underpowered—in fact, the airframe is capable of flying higher.

Rotorcraft
Rotorcraft, or rotary-wing aircraft, use a spinning rotor with aerofoil cross-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. Some have a tail rotor to counteract the rotation of the main rotor, and to aid directional control.

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.

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 Bell Boeing V-22 Osprey), tiltwing, tail-sitter, and coleopter aircraft have their rotors/propellers horizontal for vertical flight and vertical for forward flight.

Other methods of lift

 * A lifting body is an aircraft body shaped to produce lift. If there are any wings, they are too small to provide significant lift and are used only for stability and control. Lifting bodies are not efficient: they suffer from high drag, and must also travel at high speed to generate enough lift to fly. Many of the research prototypes, such as the Martin Marietta X-24, which led up to the Space Shuttle, were lifting bodies, though the Space Shuttle is not, and some supersonic missiles obtain lift from the airflow over a tubular body.
 * Powered lift types rely on engine-derived lift for vertical takeoff and landing (VTOL). Most types transition to fixed-wing lift for horizontal flight. Classes of powered lift types include VTOL jet aircraft (such as the Harrier jump jet) and tiltrotors, such as the Bell Boeing V-22 Osprey, among others. A few experimental designs rely entirely on engine thrust to provide lift throughout the whole flight, including personal fan-lift hover platforms and jetpacks. VTOL research designs include the Rolls-Royce Thrust Measuring Rig.
 * Some rotor wings employ horizontal-axis wings, in which airflow across a spinning rotor generates lift. The Flettner airplane uses a rotating cylinder, obtaining lift from the Magnus effect. The FanWing uses a cross-flow fan, while the mechanically more complex cyclogyro comprises multiple wings which rotate together around a central axis.
 * The ornithopter obtains thrust by flapping its wings.

Size
The smallest aircraft are toys/recreational items, and nano aircraft.

The largest aircraft by dimensions and volume (as of 2016) is the 302 ft long British Airlander 10, a hybrid blimp, with helicopter and fixed-wing features, and reportedly capable of speeds up to 90 mph, and an airborne endurance of two weeks with a payload of up to 22050 lbs.

The largest aircraft by weight and largest regular fixed-wing aircraft ever built,, was the Antonov An-225 Mriya. That Soviet-built (Ukrainian SSR) six-engine transport of the 1980s was 84 m long, with an 88 m wingspan. It holds the world payload record, after transporting 428834 lbs of goods, and has flown 100 t loads commercially. With a maximum loaded weight of 550-700 t, it was also the heaviest aircraft built to date. It could cruise at 500 mph. The aircraft was destroyed during the Russo-Ukrainian War.

The largest military airplanes are the Ukrainian Antonov An-124 Ruslan (world's second-largest airplane, also used as a civilian transport), and American Lockheed C-5 Galaxy transport, weighing, loaded, over 380 t. The 8-engine, piston/propeller Hughes H-4 Hercules "Spruce Goose" — an American World War II wooden flying boat transport with a greater wingspan (94m/260ft) than any current aircraft and a tail height equal to the tallest (Airbus A380-800 at 24.1m/78ft) — 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 over 400 t), and the double-decker Airbus A380 "super-jumbo" jet airliner (the world's largest passenger airliner).

Speeds
The fastest fixed-wing aircraft and fastest glider, is the Space Shuttle, which re-entered the atmosphere at nearly Mach 25 or 17,500 mph

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 9.68 or 6,755 mph on 16 November 2004.

Prior to the X-43A, the fastest recorded powered airplane flight, and still the record for the fastest manned powered airplane, was the North American X-15, rocket-powered airplane at Mach 6.7 or 7,274 km/h (4,520 mph) on 3 October 1967.

The fastest manned, air-breathing powered airplane is the Lockheed SR-71 Blackbird, a U.S. reconnaissance jet fixed-wing aircraft, having reached 3529.56 km/h on 28 July 1976.

Unpowered aircraft
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", i.e., 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
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 reciprocating 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

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.

Jet aircraft

Jet aircraft use airbreathing jet engines, which take in air, burn fuel with it in a combustion chamber, and accelerate the exhaust rearwards to provide thrust.

Different jet engine configurations include the turbojet and turbofan, sometimes with the addition of an afterburner. Those with no rotating turbomachinery include the pulsejet and ramjet. These mechanically simple engines produce no thrust when stationary, so the aircraft must be launched to flying speed using a catapult, like the V-1 flying bomb, or a rocket, for example. Other engine types include the motorjet and the dual-cycle Pratt & Whitney J58.

Compared to engines using propellers, jet engines can provide much higher thrust, higher speeds and, above about 40000 ft, 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.

Rotorcraft
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.

Other types of powered aircraft

 * Rocket-powered aircraft have occasionally been experimented with, and the Messerschmitt Me 163 Komet fighter even saw action in the Second World War. Since then, they have been restricted to research aircraft, such as the North American X-15, which traveled up into space where air-breathing engines cannot work (rockets carry their own oxidant). Rockets have more often been used as a supplement to the main power plant, typically for the rocket-assisted take off of heavily loaded aircraft, but also to provide high-speed dash capability in some hybrid designs such as the Saunders-Roe SR.53.
 * The ornithopter obtains thrust by flapping its wings. It has found practical use in a model hawk used to freeze prey animals into stillness so that they can be captured, and in toy birds.

Design and construction
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 structure ("airframe"   ) comprises the main load-bearing elements and associated equipment, as well as flight controls.
 * The propulsion system ("powerplant" ) (if it is powered) comprises the power source and associated equipment, as described above.
 * The avionics comprise the electrical and electronic control, navigation and communication systems.

Structure
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.

Aerostats
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.

Aerodynes
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.

Power
The source of motive power for an aircraft is normally called the powerplant, and includes engine or motor, propeller or rotor, (if any), jet nozzles and thrust reversers (if any), and accessories essential to the functioning of the engine or motor (e.g.: starter, ignition system, intake system, exhaust system, fuel system, lubrication system, engine cooling system, and engine controls).

Powered aircraft are typically powered by internal combustion engines (piston or turbine ) burning fossil fuels -- typically gasoline (avgas) or jet fuel. A very few are powered by rocket power, ramjet propulsion, or by electric motors, or by internal combustion engines of other types, or using other fuels. A very few have been powered, for short flights, by human muscle energy (e.g.: Gossamer Condor).

Avionics
The avionics comprise any electronic aircraft flight control systems and related equipment, including electronic cockpit instrumentation, navigation, radar, monitoring, and communications systems.

Flight envelope
The flight envelope of an aircraft refers to its approved design capabilities in terms of airspeed, load factor and altitude. The term can also refer to other assessments of aircraft performance such as maneuverability. When an aircraft is abused, for instance by diving it at too-high a speed, it is said to be flown outside the envelope, something considered foolhardy since it has been taken beyond the design limits which have been established by the manufacturer. Going beyond the envelope may have a known outcome such as flutter or entry to a non-recoverable spin (possible reasons for the boundary).

Range

The range is the distance an aircraft can fly between takeoff and landing, as limited by the time it can remain airborne.

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.

The Airbus A350-900ULR is among the longest range airliners.

Flight dynamics
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.
 * Roll is a rotation about the longitudinal axis (equivalent to the rolling or heeling of a ship) giving an up-down movement of the wing tips measured by the roll or bank angle.
 * Pitch is a rotation about the sideways horizontal axis giving an up-down movement of the aircraft nose measured by the angle of attack.
 * Yaw is a rotation about the vertical axis giving a side-to-side movement of the nose known as sideslip.

Flight dynamics is concerned with the stability and control of an aircraft's rotation about each of these axes.

Stability
An aircraft that is unstable tends to diverge from its intended flight path and so is difficult to fly. A very stable aircraft tends to stay on its flight path and is difficult to maneuver. Therefore, 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 slung underneath the center of lift.

Control
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.

Environmental impact
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.

Uses for aircraft
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.

Military

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:

 * Combat aircraft are aircraft designed to destroy enemy equipment using its own armament. Combat aircraft divide broadly into fighters and bombers, with several in-between types, such as fighter-bombers and attack aircraft, including attack helicopters.
 * Non-combat aircraft are not designed for combat as their primary function, but may carry weapons for self-defense. Non-combat roles include search and rescue, reconnaissance, observation, transport, training, and aerial refueling. These aircraft are often variants of civil aircraft.

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

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.

Experimental
An experimental aircraft is one that has not been fully proven in flight, or that carries a Special Airworthiness Certificate, called an Experimental Certificate in United States parlance. This often implies that the aircraft is testing new aerospace technologies, though the term also refers to amateur-built and kit-built aircraft, many of which are based on proven designs.

Model
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.

Lists

 * Early flying machines
 * Flight altitude record
 * List of aircraft
 * List of civil aircraft
 * List of fighter aircraft
 * List of individual aircraft
 * List of large aircraft
 * List of aviation, aerospace and aeronautical terms

Topics

 * Aircraft hijacking
 * Aircraft spotting
 * Air traffic control
 * Airport
 * Flying car
 * Personal air vehicle
 * Powered parachute
 * Spacecraft
 * Spaceplane

History

 * The Evolution of Modern Aircraft (NASA)
 * Virtual Museum
 * Smithsonian Air and Space Museum - online collection with a particular focus on history of aircraft and spacecraft
 * Amazing Early Flying Machines slideshow by Life magazine

Information

 * Airliners.net
 * Aviation Dictionary - free aviation terms, phrases and jargons
 * New Scientist's aviation page

license: Creative Commons - Attribution Share-Alike - https://creativecommons.org/licenses/by-sa/4.0/

title: Aircraft