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107-431: The PPV may be considered a forerunner of the modern velomobile . This tricycle was manufactured with a three-speed, floor shift, open type transmission with a single-wheel drive. Either the driver or the passenger could pedal independently or as a team. Reverse was accomplished by reaching outside and turning one of the rear wheels by hand. At one time, a rear-hinged, surrey top was available. Most were manufactured with

214-399: A basic plane and must then be completed by the builder. Few companies produce planes on a large scale. However, the production of a plane for one company is a process that actually involves dozens, or even hundreds, of other companies and plants, that produce the parts that go into the plane. For example, one company can be responsible for the production of the landing gear, while another one

321-497: A bicycle that it does not fall over when stopped. In addition, when a cross-wind hits a fairing, it makes a big force; faired tricycles are less likely to get blown over than faired bicycles. Although three wheels have practical advantages, they also have more aerodynamic drag than two wheels, so land speed record cycles are often bicycles. Although four wheels were used as far back as the Velocar, they are not today common. As of 2017, there

428-606: A box or bag of dimensions similar to the frame. In turn, this makes velomobiles more difficult to transport. Velomobiles are often built using some standard bicycle parts, but also many parts specific to velomobiles or even specific to a particular make or model. In addition, the bodywork is large and may be around half the weight of a velomobile. Thus, to reduce weight, the body is often made of lighter but more expensive materials. Also, production volumes are low, so for both parts and labor there are not benefits of mass production—as of 2017 , many velomobile makers have yearly production on

535-466: A canopy. Thus, a "high speed" velomobile may benefit most from better aerodynamics, even when aerodynamics hurts rider cooling; while at the same time a "high load" velomobile may benefit most from improved cooling (to maximize power output) even if that hurts aerodynamics. Velomobiles are significantly bulkier than conventional cycles. Further, the bodywork typically cannot be disassembled much, whereas conventional cycles often can be disassembled to fit in

642-414: A car or road-side shrubbery, fences, etc. The fairing on a velomobile sometimes makes it more subject to cross-winds than a similar unfaired cycle. The effect of cross-winds is complicated because the force of the wind can act as a steering force, as-if the rider had tried to steer the cycle. "Wind steer" can be a safety issue and may also hurt performance, as a serpentine path is longer and thus slower than

749-565: A combustion chamber or a solid fuel with oxidizer may burn in the fuel chamber. Whether liquid or solid-fueled, the hot gas is accelerated through a nozzle. In World War II , the Germans deployed the Me 163 Komet rocket-powered aircraft . The first plane to break the sound barrier in level flight was a rocket plane – the Bell X-1 in 1948. The North American X-15 broke many speed and altitude records in

856-650: A conventional single-rider bicycle (an Atom drum brake built in to the front wheel). Thus, even at relaxed speeds on level ground, the PPV brakes were dangerously inadequate. An upgraded version of this vehicle is currently (2011) being offered by the International Surrey Company Ltd. under the trade name Impello. This vehicle-related article is a stub . You can help Misplaced Pages by expanding it . Velomobile A velomobile ( / ˈ v ɛ l oʊ m oʊ ˌ b i l / ); velomobiel , velo , or bicycle car

963-418: A country and even between cities in a region. For example, a specific vehicle may be a "bicycle" in one area, a "low-speed pedal-assisted cycle" in another area, and a " moped " in yet a third. Similarly, going from 3 wheels to 4 wheels can change the category of an otherwise identical vehicle. One reason for the varying treatment is that many laws are older than widespread use of power-assisted velomobiles and so

1070-443: A dark blue bottom and a white hood. Red or yellow bottoms with white tops were also offered. Sometimes bicycle accessories were added, e.g. squeeze bulb horn and a rear view mirror. The PPV was designed for two adult riders, and with frame and body the total weight could approach three times that of a conventional single-rider bicycle. However, the PPV was fitted with just one brake, of a type intended to be just one of two brakes on

1177-410: A few, and some riders report speeds are close to three-wheel velomobiles with highly aerodynamic fairings. Two-wheel "streamliner" configurations can have much less aerodynamic drag: wheels are hard to make aerodynamic; each wheel entry/exit to the fairing adds drag; and velomobiles with two front wheels are necessarily wider or longer than the rider, while two-wheel streamliners can be barely wider than

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1284-737: A first flight. The flight tests continue until the aircraft has fulfilled all the requirements. Then, the governing public agency of aviation of the country authorizes the company to begin production. In the United States, this agency is the Federal Aviation Administration (FAA). In the European Union, European Aviation Safety Agency (EASA); in the United Kingdom it is the Civil Aviation Authority (CAA). In Canada,

1391-468: A form of roll control supplied either by wing warping or by ailerons and controlled by its pilot with a joystick and rudder bar. It was an important predecessor of his later Blériot XI Channel -crossing aircraft of the summer of 1909. World War I served as a testbed for the use of the airplane as a weapon. Airplanes demonstrated their potential as mobile observation platforms, then proved themselves to be machines of war capable of causing casualties to

1498-412: A frame and made rigid by the lift forces exerted by the airflow over them. Larger aircraft have rigid wing surfaces which provide additional strength. Whether flexible or rigid, most wings have a strong frame to give them their shape and to transfer lift from the wing surface to the rest of the aircraft. The main structural elements are one or more spars running from root to tip, and many ribs running from

1605-453: A front bottom bracket with one or more chainrings , and a rear derailleur . Depending on the configuration of the velomobile there may be any number of idler pulleys, and chaintubes along the drive train to manage and protect the chain. One of the defining characteristics of most velomobiles is that the chain and drivetrain components are protected from weather and the road. Before World War II, Charles Mochet  [ fr ] built

1712-414: A given level of effort. In some situations, a rider's power output (for any type of cycle) is limited by body temperature, and the worse cooling of a velomobile can limit the rider's power output more than on an unfaired cycle. With an aerodynamic fairing, the velomobile rider at reduced power output may still be faster than an unfaired cycle, due to the lower aerodynamic drag. A velomobile's fairing shields

1819-426: A given terrain, the added weight demands lower gearing and makes the velomobile slower climbing hills than its unfaired counterpart. Some velomobile fairings are mainly for weather protection. However, if the velomobile fairing is substantially streamlined, then improved aerodynamics means the speeds on flats and down hills may be substantially higher than its unfaired counterpart, and often enough faster to make up for

1926-414: A jet-powered aircraft with a speed of Mach 9.7, nearly 12,100 kilometers per hour (7,500 mph). Whereas jet aircraft use the atmosphere both as a source of oxidant and of mass to accelerate reactively behind the aircraft, rocket aircraft carry the oxidizer on board and accelerate the burned fuel and oxidizer backwards as the sole source of mass for reaction. Liquid fuel and oxidizer may be pumped into

2033-420: A liquid that dries and shrinks the fabric to a tight fit on the wire/tube supports. The approach was used widely on early airplanes , and has the advantage of light weight with relatively low-technology materials. It is sometimes called "bird cage" construction because the support looks similar to closely spaced wires used in construction of bird cages , and because the wire/tube support outline shows through once

2140-443: A longer "tail" on the fairing will increase the total side-wind profile and total side forces, but can reduce the percentage force acting on the steered wheels and so an improve stability in side winds. A larger fairing also hurts weight and has more skin drag ), but as with time-trial bicycles, worse aerodynamics but better handling is sometimes a good trade-off. Velomobiles with fairings that are mainly for weather protection can use

2247-483: A mass-produced velomobile, which was in the mid-1980s, flopped. This was the Sinclair C5 . The C5 was a delta trike (one front, two rear wheels) with electric assist designed to be mass-produced and sold for a low price. The C5 was poorly designed; it was heavy, had only one gear and had no adjustment for the distance between the pedals and the seat, which is important to get a comfortable pedalling position. A concept and

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2354-424: A more upright seating position. This tends to improve both the ability to see and be seen. However, to retain stability against tipping (both cornering and cross-winds), the wheel track needs to be wider than a comparable velomobile with a low seating position. In turn, this may make the velomobile quite a bit wider than a conventional cycle. "Weather" protection includes cold and wet, but also shading from sun. Since

2461-679: A potential assessment concerning low-cost velomobiles for daily short trips as well as strategies for reaching a critical lot size for mass production was the subject of a research project called RegInnoMobil. Velomobiles have also been used in Australian HPV Super Series since 1985, and more recently, other events in Australia like the RACV Energy Breakthrough , the Fraser Coast Technology Challenge , and

2568-538: A presence in all the major battles of World War II . The first jet aircraft was the German Heinkel He 178 in 1939. The first jet airliner , the de Havilland Comet , was introduced in 1952. The Boeing 707 , the first widely successful commercial jet, was in commercial service for more than 60 years, from 1958 to 2019. First attested in English in the late 19th century (prior to the first sustained powered flight),

2675-418: A production version called Leitra . Leitra velomobiles have been in continuous production since then (as of 2017), with current models evolved/improved from the originals. There are many ways to build a velomobile. One modern design is "body-on-frame", in which a velomobile is made from a not-faired cycle plus a body. A standard cycle may be used, but often a custom cycle is used with special fittings to mount

2782-416: A propeller creates is determined, in part, by its disk area—the area through which the blades rotate. The limitation on blade speed is the speed of sound ; as when the blade tip exceeds the speed of sound, shock waves decrease propeller efficiency. The rpm required to generate a given tip speed is inversely proportional to the diameter of the propeller. The upper design speed limit for propeller-driven aircraft

2889-572: A range of features—for example, there are Milan models used in racing but also a Milan "cargo" model with enough luggage volume to carry a (not-pedaling) human passenger and other bulky items. All current (2017) velomobiles are produced in low volume, with "big" makers producing one or a few velomobiles per week. Velomobiles use some standard bicycle parts, but also many parts specific to velomobiles, and thus made in low volume. The use of "more parts" (e.g., 3 wheels instead of 2) and "more low-volume" parts makes velomobiles more expensive. The only attempt at

2996-582: A recently restored version weighs 59 kg or 130 lb. However, it had flaws in the execution that doomed it as a practical, everyday vehicle . Positive features, such as easily adjustable and comfortable seats, independent pedalling for both passenger and driver, adequate cargo space and relatively good weather protection, could not overcome the negative features, such as a complex, heavy and badly spaced three-speed gear box, ineffective brakes , and pedals that slid on sleeve bearings on steel shafts, which made it difficult to use as an everyday vehicle. In Sweden ,

3103-477: A shaft through a reduction gearing to the propeller. The propelling nozzle provides a relatively small proportion of the thrust generated by a turboprop. An electric aircraft runs on electric motors with electricity coming from fuel cells , solar cells , ultracapacitors , power beaming , or batteries . Currently, flying electric aircraft are mostly experimental prototypes, including manned and unmanned aerial vehicles , but there are some production models on

3210-403: A significantly narrower "useful" width, as the road contact is in the center and so the rider's hands/elbows/etc. might overhang the edge of the roadway or path without causing problems. In contrast, the wheel track of a velomobile is very nearly as wide as the vehicle itself, and so cannot overhang the edge. The steered wheels on a velomobile will hit the fairing if steered sharply enough. Making

3317-410: A single wheel is the simplest and lightest approach. Driving both wheels can improve traction but also increases complexity, cost, and weight. A solid axle may be used, but increases friction/drag in corners and thus can slow down the vehicle. One alternative is a differential , which is the approach used in most cars. A second alternative is to use a pair of ratchets, where the slower wheel is driven and

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3424-426: A single wing plane, a biplane has two stacked one above the other, a tandem wing has two placed one behind the other. When the available engine power increased during the 1920s and 30s and bracing was no longer needed, the unbraced or cantilever monoplane became the most common form of powered type. The wing planform is the shape when seen from above. To be aerodynamically efficient, a wing should be straight with

3531-435: A small and simple engine for high-speed use, such as with missiles. Ramjets require forward motion before they can generate thrust and so are often used in conjunction with other forms of propulsion, or with an external means of achieving sufficient speed. The Lockheed D-21 was a Mach 3+ ramjet-powered reconnaissance drone that was launched from a parent aircraft . A ramjet uses the vehicle's forward motion to force air through

3638-432: A small four-wheeled 'bike'-car for his son. Mochet built many models of small vehicles called " Velocar ". Some models had two seats, most were pedal powered, but as the years went by, many were fitted with small engines . Mochet Velocars use a thin wood/plywood body on a steel frame. Some other early velomobiles use a fabric body or "skin" sewn to fit loosely on closely spaced wires or tubes, then painted or "doped" with

3745-468: A span of 14 m (46 ft). All-up weight was 300 kilograms (660 lb). On 9 October 1890, Ader attempted to fly the Éole . Aviation historians give credit to this effort as a powered take-off and uncontrolled hop of approximately 50 m (160 ft) at a height of approximately 200 mm (7.9 in). Ader's two subsequent machines were not documented to have achieved flight. The American Wright brothers 's flights in 1903 are recognized by

3852-409: A straight line. Thus, a design with inferior aerodynamics may be better overall. For example, it is common for time-trial bicycles to use a solid disk rear wheel for best aerodynamics, and a spoked front wheel that has worse aerodynamics than a disk, but is less likely to steer the bicycle in a cross-wind. Velomobile fairings have analogous concerns, leading to trade-offs in fairing design. For example,

3959-477: A two-seat design called Fantom was sold as blueprints and became very popular; over 100,000 copies of the blueprints were sold, but few were actually completed. The downfall of these early 'bicycle' cars came when the economy improved and people chose automobiles . Builders continued to make "one-off" velomobiles, but for a time none were available commercially. In the 1970s, Carl-Georg Rasmussen rediscovered Fantomen ; he redesigned it and in 1983 started selling

4066-461: A type of rotary aircraft engine, he did not create and fly a powered fixed-wing aircraft. The Frenchman Clement Ader constructed his first of three flying machines in 1886, the Éole . It was a bat-like design run by a lightweight steam engine of his own invention, with four cylinders developing 20 horsepower (15  kW ), driving a four-blade propeller . The engine weighed no more than 4 kilograms per kilowatt (6.6 lb/hp). The wings had

4173-486: Is Mach 0.6. Aircraft designed to go faster than that employ jet engines. Reciprocating engines in aircraft have three main variants, radial , in-line and flat or horizontally opposed engine . The radial engine is a reciprocating type internal combustion engine configuration in which the cylinders "radiate" outward from a central crankcase like the spokes of a wheel and was commonly used for aircraft engines before gas turbine engines became predominant. An inline engine

4280-508: Is a fixed-wing aircraft that is propelled forward by thrust from a jet engine , propeller , or rocket engine . Airplanes come in a variety of sizes, shapes, and wing configurations . The broad spectrum of uses for airplanes includes recreation , transportation of goods and people, military , and research . Worldwide, commercial aviation transports more than four billion passengers annually on airliners and transports more than 200 billion tonne - kilometers of cargo annually, which

4387-556: Is a human-powered vehicle (HPV) enclosed for aerodynamic advantage and/or protection from weather and collisions. Velomobiles are similar to recumbent bicycles , pedal go-karts and tricycles , but with a full fairing (aerodynamic or weather protective shell) and are not to be confused with purpose-built mobiles for speed records. Fully faired vehicles with two wheels, generally called Streamliners . Streamliners have set many speed and distance records. Though fast in their own right, velomobiles are considered much more suitable for

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4494-517: Is a monocoque shell, often made of fiber-reinforced plastic or "FRP", plus sub-frames of welded aluminum tubes. FRP can be used to produce a wide range of shapes, and thus can improve aerodynamics over approaches such as "birdcage" and aluminum-sheet monocoque. FRP can also use fibers with high strength-to-weight ratio that in velomobiles can save several kilograms compared to other designs. A wide range of fibers may be used, but those which reduce weight while retaining strength and toughness often increase

4601-421: Is a reciprocating engine with banks of cylinders, one behind another, rather than rows of cylinders, with each bank having any number of cylinders, but rarely more than six, and may be water-cooled. A flat engine is an internal combustion engine with horizontally-opposed cylinders. A turboprop gas turbine engine consists of an intake, compressor, combustor, turbine, and a propelling nozzle, which provide power from

4708-587: Is at least one 4-wheel production model, the QuattroVelo . Four wheels tends to further hurt aerodynamics and weight compared to three; but for a given width, four wheels is much more laterally stable than three wheels. Also, four wheels can be placed in a way that increases luggage capacity a lot compared to three-wheel designs. Most velomobiles drive the rear wheel(s). This approach is simple and can often use many standard bicycle parts. Velomobiles with two rear wheels may drive just one wheel, or may drive both. Driving

4815-420: Is less than 1% of the world's cargo movement. Most airplanes are flown by a pilot on board the aircraft, but some are designed to be remotely or computer-controlled such as drones. The Wright brothers invented and flew the first airplane in 1903, recognized as "the first sustained and controlled heavier-than-air powered flight". They built on the works of George Cayley dating from 1799, when he set forth

4922-511: Is often higher than alternatives, as the body does have some intrinsic strength, yet this is not used to reduce the weight of the frame. Another modern design is the Alleweder  [ de ] , using aluminum sheet formed and riveted to make the fairing and the structure in one piece. This approach is sometimes called monocoque or "unit" construction; it was used in airplanes before 1920. Labor costs to build an Alleweder are significant due to

5029-441: Is provided to assist the driver's leg muscle effort. Most electric-assist propulsion motors are of the in-wheel design in the rear wheel, such as geared hub motors (like eZee, Heinzmann, Bafang, BMC, etc.) and direct-drive hub motors (like Crystalyte, BionX, 9Continent, etc.) but mid-drive units (like Sunstar, Cyclone, Ecospeed, etc.) are used as well due to design constraints in velomobile models with one-sided rear wheel mounting like

5136-420: Is responsible for the radar. The production of such parts is not limited to the same city or country; in the case of large plane manufacturing companies, such parts can come from all over the world. The parts are sent to the main plant of the plane company, where the production line is located. In the case of large planes, production lines dedicated to the assembly of certain parts of the plane can exist, especially

5243-557: The Fédération Aéronautique Internationale (FAI), the standard-setting and record-keeping body for aeronautics , as "the first sustained and controlled heavier-than-air powered flight". By 1905, the Wright Flyer III was capable of fully controllable, stable flight for substantial periods. The Wright brothers credited Otto Lilienthal as a major inspiration for their decision to pursue manned flight. In 1906,

5350-565: The Victorian HPV Series . In 2018, Dave Lewis set a new race record at the Sebring 24 hour race using a DF velomobile made by Intercitybike.nl. Velomobiles also competed in the ultra endurance Trans Am Bike race and came in 1st (setting a new record) and 4th places. 1st place was Marcel Graber and 4th Dave Lewis. In 2010 the Milan SL was used by Christian von Ascheberg , to set a record in

5457-451: The 11th-century English monk Eilmer of Malmesbury ; both experiments injured their pilots. Leonardo da Vinci researched the wing design of birds and designed a man-powered aircraft in his Codex on the Flight of Birds (1502), noting for the first time the distinction between the center of mass and the center of pressure of flying birds. In 1799, George Cayley set forth the concept of

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5564-602: The 1920s and 30s, wings could be made heavy and strong enough that bracing was not needed any more. This type of unbraced wing is called a cantilever wing. The number and shape of the wings varies widely on different types. A given wing plane may be full-span or divided by a central fuselage into port (left) and starboard (right) wings. Occasionally, even more wings have been used, with the three-winged triplane achieving some fame in WWI. The four-winged quadruplane and other multiplane designs have had little success. A monoplane has

5671-458: The 1960s and pioneered engineering concepts for later aircraft and spacecraft. Military transport aircraft may employ rocket-assisted take offs for short-field situations. Otherwise, rocket aircraft include spaceplanes , like SpaceShipTwo , for travel beyond the Earth's atmosphere and sport aircraft developed for the short-lived Rocket Racing League . Most airplanes are constructed by companies with

5778-635: The 24 hours (1219 km) and 1000 km (19h27m) category. In 2015 Petra von Fintel set a 24 hours world record at 1012km in a Milan SL In 2022 Nicola Walde set the current 24 hours world record at 1130km In summer 2023 Matthias König set a new 6 hour world record in a Snoek (388km) while Ruben Schütz set a new 24 hours record (1256 km) in a Milan SL Mk7 at the Record Weekend in Aldehoven. The velomobile fairing adds weight compared to standard upright cycles or unfaired recumbent cycles. For

5885-715: The Brazilian Alberto Santos-Dumont made what was claimed to be the first airplane flight unassisted by catapult and set the first world record recognized by the Aéro-Club de France by flying 220 meters (720 ft) in less than 22 seconds. This flight was also certified by the FAI. An early aircraft design that brought together the modern monoplane tractor configuration was the Blériot VIII design of 1908. It had movable tail surfaces controlling both yaw and pitch,

5992-617: The Concorde to remove it from service. An aircraft propeller , or airscrew , converts rotary motion from an engine or other power source, into a swirling slipstream which pushes the propeller forwards or backwards. It comprises a rotating power-driven hub, to which are attached two or more radial airfoil -section blades such that the whole assembly rotates about a longitudinal axis. Three types of aviation engines used to power propellers include reciprocating engines (or piston engines), gas turbines , and electric motors . The amount of thrust

6099-913: The DIY velomobiles from kits tend to be less expensive. Probably the most built velomobile kits were the various models of the Alleweder made from prefabricated aluminium sheet metal due to its affordable price. Due to low demand, the Alleweder A4 kit was discontinued in 2020. As of 2024, no major velomobile manufacturer offers velomobile kits. Many amateur velomobile builders are also recumbent bike riders. In more recent years many online velomobile groups, some of them focusing on specific regions, have appeared, on Facebook and on other platforms. Velomobile Seminars online - resources available for free download, mostly in English with some German language material. Airplanes An airplane ( North American English ) or aeroplane ( British English ), informally plane ,

6206-520: The Quest, Strada and Mango or front wheel drive in the Velayo, or better efficiency by using the multiple speeds of the chain drive or internal geared hubs (e.g. Rohloff 14 speed hub). While an electric-assist unit does add extra weight to the velomobile, it is somewhat offset by the flexibility it also provides, especially during hill climbs and stop-and-go traffic. Due to vastly better aerodynamics of velomobiles

6313-591: The Russian Alexander F. Mozhaisky also made some innovative designs. In 1883, the American John J. Montgomery made a controlled flight in a glider. Other aviators who made similar flights at that time were Otto Lilienthal , Percy Pilcher , and Octave Chanute . Sir Hiram Maxim built a craft that weighed 3.5 tons, with a 110-foot (34 m) wingspan that was powered by two 360-horsepower (270 kW) steam engines driving two propellers. In 1894, his machine

6420-485: The air entering the engine must be decelerated to a subsonic speed and then re-accelerated back to supersonic speeds after combustion. An afterburner may be used on combat aircraft to increase power for short periods of time by injecting fuel directly into the hot exhaust gases. Many jet aircraft also use thrust reversers to slow down after landing. A ramjet is a form of jet engine that contains no major moving parts and can be particularly useful in applications requiring

6527-402: The amount and the kinds of grit landing on the drivetrain. Some cycles use tooth-belt drive, which is less affected by grit, is quieter than a chain, and may be lighter. However, belts are only available in pre-selected sizes. Many recumbent cycles, including most velomobiles, have a long drivetrain for which no suitable tooth belts are available. Velomobile bodies are typically light enough that

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6634-437: The behavior of the aircraft. Computers are used by companies to draw, plan and do initial simulations of the aircraft. Small models and mockups of all or certain parts of the plane are then tested in wind tunnels to verify its aerodynamics. When the design has passed through these processes, the company constructs a limited number of prototypes for testing on the ground. Representatives from an aviation governing agency often make

6741-399: The body; the use of special fittings tends to improve fit and durability, and can also reduce weight. Body-on-frame construction allows flexible configuration: the body may be of any construction, as it does not need to be self-supporting, and various bodies can be used with various frames. Also, the body may be removed so the cycle alone can be used. However, the overall weight of body-on-frame

6848-894: The case of international sales, a license from the public agency of aviation or transport of the country where the aircraft is to be used is also necessary. For example, airplanes made by the European company, Airbus , need to be certified by the FAA to be flown in the United States, and airplanes made by U.S.-based Boeing need to be approved by the EASA to be flown in the European Union. Regulations have resulted in reduced noise from aircraft engines in response to increased noise pollution from growth in air traffic over urban areas near airports. Small planes can be designed and constructed by amateurs as homebuilts. Other homebuilt aircraft can be assembled using pre-manufactured kits of parts that can be assembled into

6955-482: The center of mass is similar to the center of mass on an unfaired recumbent cycle. This makes cornering stability similar to similar unfaired cycles. However, minimizing velomobile width also contributes to reduced frontal area and thus drag; so there is an additional incentive to make the velomobile narrow. The narrowest velomobiles are only slightly wider than the rider's shoulders, and so the width approaches that of an upright bicycle. However, an upright bicycle still has

7062-426: The combustion air, prior to the introduction and ignition of fuel. Rocket motors provide thrust by burning a fuel with an oxidizer and expelling gas through a nozzle. Most jet aircraft use turbofan jet engines, which employ a gas turbine to drive a ducted fan, which accelerates air around the turbine to provide thrust in addition to that which is accelerated through the turbine. The ratio of air passing around

7169-479: The concept of the modern airplane (and later built and flew models and successful passenger-carrying gliders ) and the work of German pioneer of human aviation Otto Lilienthal , who, between 1867 and 1896, also studied heavier-than-air flight. Lilienthal's flight attempts in 1891 are seen as the beginning of human flight. Following its limited use in World War I , aircraft technology continued to develop. Airplanes had

7276-507: The concept of the modern wing, his flight attempts in 1891 are seen as the beginning of human flight, the " Lilienthal Normalsegelapparat " is considered to be the first airplane in series production and his work heavily inspired the Wright brothers. In the 1890s, Lawrence Hargrave conducted research on wing structures and developed a box kite that lifted the weight of a man. His box kite designs were widely adopted. Although he also developed

7383-422: The drivetrain from weather, as well as the rider. Drivetrain maintenance is often reduced compared to other cycles, especially unfaired bicycles, where the front wheel kicks up grit-containing dust, mud, and dirty water that lands directly on the chain and increases the rate of abrasive wear on the drivetrain—including chain and sprockets, but sometimes also derailleurs. The fairing of a velomobile tends to limit both

7490-479: The end of WWII all-metal aircraft were common. In modern times, increasing use of composite materials has been made. Typical structural parts include: The wings of a fixed-wing aircraft are static planes extending either side of the aircraft. When the aircraft travels forwards, air flows over the wings, which are shaped to create lift. This shape is called an airfoil and is shaped like a bird's wing. Airplanes have flexible wing surfaces which are stretched across

7597-527: The enemy. The earliest known aerial victory with a synchronized machine gun-armed fighter aircraft occurred in 1915, by German Luftstreitkräfte Leutnant Kurt Wintgens . Fighter aces appeared; the greatest (by number of Aerial Combat victories) was Manfred von Richthofen , also known as the Red Baron. Following WWI, aircraft technology continued to develop. Alcock and Brown crossed the Atlantic non-stop for

7704-426: The engine without resorting to turbines or vanes. Fuel is added and ignited, which heats and expands the air to provide thrust. A scramjet is a specialized ramjet that uses internal supersonic airflow to compress, combine with fuel, combust and accelerate the exhaust to provide thrust. The engine operates at supersonic speeds only. The NASA X-43 , an experimental unmanned scramjet, set a world speed record in 2004 for

7811-523: The fabric is tight. Some disadvantages of this approach are the cost of construction, due to the many interconnected supports; and that the shape is that of many flat panels, which limits smoothness of the skin and thus limits the aerodynamics. In the 1970s, the People Powered Vehicle was produced. It was a two-seat, "sociable" tandem with a steel sub frame and molded plastic body. It was well designed and weighed something over 50 kg (110 lb );

7918-427: The fairing wider can give space to steer the wheels more sharply, but has down-sides for aerodynamics and width. Although sharp steering is not needed at speed, many aerodynamic velomobiles have a much worse turning circle than an equivalent unfaired cycle. In contrast an unfaired cycle cannot have fairing interference, and so even with the same wheel and rider configuration can steer a much tighter circle. Steering only

8025-476: The faster wheel coasts. Rear drive often uses "idler" pulleys to route the chain; front-wheel drive can eliminate idlers, so offers less friction and also less weight. It can also increase luggage capacity. However, front drive with two front wheels uses some non-standard components, and as of 2017 is used only rarely. As with other cycles, a velomobile may use suspension. Suspension tends to improve rider comfort, and can also improve speed—it takes energy to "bounce"

8132-609: The first time in 1919. The first international commercial flights took place between the United States and Canada in 1919. Airplanes had a presence in all the major battles of World War II . They were an essential component of the military strategies of the period, such as the German Blitzkrieg , The Battle of Britain , and the American and Japanese aircraft carrier campaigns of the Pacific War . The first practical jet aircraft

8239-448: The laws were not written to consider such vehicles. In some areas, laws are being rewritten to include power-assist velomobiles and to harmonize treatment with nearby laws. With a growing DIY -community and an increasing interest in environmentally friendly " green energy ", some hobbyists have endeavored to build their own velomobiles from kits, sourced components, or from scratch. When compared to similar sized commercial velomobiles,

8346-399: The leading (front) to the trailing (rear) edge. Early airplane engines had little power, and lightness was very important. Also, early airfoil sections were very thin, and could not have a strong frame installed within. So, until the 1930s, most wings were too lightweight to have enough strength, and external bracing struts and wires were added. When the available engine power increased during

8453-422: The manufacturer or the customer. The structural parts of a fixed-wing aircraft are called the airframe. The parts present can vary according to the aircraft's type and purpose. Early types were usually made of wood with fabric wing surfaces, When engines became available for powered flight around a hundred years ago, their mounts were made of metal. Then as speeds increased more and more parts became metal until by

8560-489: The many rivets and rivet holes. Also, the choices of aerodynamic shapes are limited by the formability of the aluminum sheet. That said, aluminum is relatively inexpensive, and as of 2017 Alleweders can be often be bought for less than other designs; they can also be bought as kits, to reduce out-of-pocket cost. Aluminum can also be repaired relatively easily, and aluminum, which is homogeneous, can be recycled more easily than many composite materials. Another common modern design

8667-440: The market. Jet aircraft are propelled by jet engines , which are used because the aerodynamic limitations of propellers do not apply to jet propulsion. These engines are much more powerful than a reciprocating engine for a given size or weight and are comparatively quiet and work well at higher altitude. Variants of the jet engine include the ramjet and the scramjet , which rely on high airspeed and intake geometry to compress

8774-406: The modern airplane as a fixed-wing flying machine with separate systems for lift, propulsion, and control. Cayley was building and flying models of fixed-wing aircraft as early as 1803, and he built a successful passenger-carrying glider in 1853. In 1856, Frenchman Jean-Marie Le Bris made the first powered flight, by having his glider "L'Albatros artificiel" pulled by a horse on a beach. Then

8881-405: The objective of producing them in quantity for customers. The design and planning process, including safety tests, can last up to four years for small turboprops or longer for larger planes. During this process, the objectives and design specifications of the aircraft are established. First the construction company uses drawings and equations, simulations, wind tunnel tests and experience to predict

8988-411: The operator's head exposed; this has the advantage of giving the operator unobstructed vision, hearing, and some cooling, with the disadvantage of being potentially more exposed to weather and less aerodynamic. Fully enclosed machines can suffer from heat or humidity issues as well as potential noise issues. The typical drive train of a velomobile is not unlike a bicycle or recumbent. It will consist of

9095-455: The order of tens or maybe a few hundred velomobiles. Taken together, these factors mean velomobiles are often much more expensive than other cycle types. As an example of prices and price/weight tradeoffs, as of April 2017 the maker Trisled offers their "Rotovelo" model either with a rotational molded plastic fairing or with a carbon fiber fairing (as well as some other weight-saving changes). The body shapes and underlying framework are similar;

9202-446: The price significantly—e.g., a premium of 1000 Euros to save 3 kg. In addition, it is often hard to segregate and recycle the FRP materials. But despite the cost and other issues, the aerodynamic and weight advantages mean that (as of 2017) monocoque FRP is a common way to build velomobiles. As of 2017, most velomobiles are tricycles with two front wheels. A tricycle has the advantage over

9309-578: The public agency in charge and authorizing the mass production of aircraft is Transport Canada's Civil Aviation Authority. When a part or component needs to be joined together by welding for virtually any aerospace or defense application, it must meet the most stringent and specific safety regulations and standards. Nadcap , or the National Aerospace and Defense Contractors Accreditation Program sets global requirements for quality, quality management and quality assurance for aerospace engineering. In

9416-504: The range of a similar electric assist unit and similar battery in a velomobile can be about 50% to 100% higher compared to upright bicycles or unfaired recumbents. In events like the RACV Energy Breakthrough and the Fraser Coast Technology Challenge , there are entire categories dedicated to electric and other hybrid powered velomobiles. The legal definition of "bicycle" often includes velomobiles, but laws covering cycles with electric assist vary widely across countries and often within

9523-418: The rear wheel(s) would avoid fairing interference, but it is hard to build a stable vehicle using only rear-wheel steering . The Velayo uses a tricycle configuration and steers only the rear wheel; but it is produced only in small numbers. The experimental Kingsbury Fortuna and Quattro velomobiles steered all wheels ; this approach avoids some of the stability problems of rear-wheel steering while still reducing

9630-428: The rider is doing work, it is typically desirable to have at least some cooling. Many velomobiles have vents and ducts which allow cooling while keeping out water; and the ducts/vents may be closed or covered in cold weather so the rider can stay comfortable even without a secondary heat source. In warm and hot weather, the fairing provides sun protection, but blocks the rider from cooling air, and so may be much warmer for

9737-499: The rider. A common way to describe aerodynamic drag is "CdA"; in one comparison of racing cycles, there were several two-wheel streamliners with less than half the CdA drag of the best three-wheeler. Air drag is most significant for high-speed events; as of 2016, the world record for a 200-metre sprint on near-level ground is about 145 km/h for a two-wheel streamliner and about 120 km/h for any vehicle with more than two wheels, meaning

9844-426: The rotational-molded version weighs 33 kilograms and has a list price of Au$ 6500, while the carbon fiber version weighs 20 kilograms and has a list price of Au$ 10900. Much of the cycle-related infrastructure design is based on the typical configuration of an upright bicycle. For example, multi-modal transportation such as bike/train/bike routes often use bicycle racks in the train, and the dimensions of racks and also

9951-441: The slower climbing due to weight. An aerodynamic fairing must be well-shaped, but minimizing the frontal area of the velomobile is also important to reduced drag: a fairing with half the frontal area may approach half the air drag. In turn, aerodynamic velomobiles use a laid-back or recumbent riding position, with the rider's head much lower than on regular bicycles. In turn, velomobile is much easier to accidentally "hide" behind

10058-526: The steering angle of the front wheels. However, this approach has not (as of 2017) gained wider use in velomobiles. As of 2017, most velomobiles use a tadpole recumbent tricycle configuration — mainly to reduce component weight and improve wheel aerodynamics. However, some use a four-wheel or quadracycle configuration. The extra wheel significantly improves cornering stability and can also improve luggage capacity. As of 2017 there are not many four-wheel velomobiles with highly aerodynamic fairings, but there are

10165-567: The street than two-wheeled streamliners. Using three or more wheels can have advantages for everyday use, including the ability to stop and start unaided, better stability, cross-wind handling, etc., though there are arguments made that the multiple track machines (three or more wheels) have aerodynamic disadvantages due to the drag of the extra wheels and the surface contact points. In practice though, velomobiles continue to be close to their two-wheel cousins in performance. There are few velomobile manufacturers ; some are home-built. Some models have

10272-601: The term "airplane" is used for powered fixed-wing aircraft. In the United Kingdom and Ireland and most of the Commonwealth , the term "aeroplane" ( / ˈ ɛər ə p l eɪ n / ) is usually applied to these aircraft. Many stories from antiquity involve flight, such as the Greek legend of Icarus and Daedalus , and the Vimana in ancient Indian epics . Around 400 BC in Greece , Archytas

10379-433: The train ingress/egress assume a conventional cycle. Similarly, cycle paths often have bollards or S-bend paths to prevent motor vehicle entry, and the entry is often spaced for upright bicycles, but may be too narrow or require too sharp of a turn to allow through some velomobiles. Some velomobiles have been converted to provide electric assist. Electric assist means that a small battery-operated electric-propulsion system

10486-408: The turbine to that passing through is called the by-pass ratio . They represent a compromise between turbojet (with no bypass) and turboprop forms of aircraft propulsion (primarily powered with bypass air). Subsonic aircraft, such as airliners, employ high by-pass jet engines for fuel efficiency. Supersonic aircraft , such as jet fighters, use low-bypass turbofans. However at supersonic speeds,

10593-463: The two-wheel vehicle was about 20% faster. Aerodynamic power is roughly cubic in speed, so at lower speeds the difference is much less pronounced. At the same time, two-wheel streamliners require a way to stay upright when stopped and at very low speed, and are more sensitive to blowing over in cross-winds. These factors limit the use of streamliners, despite their aerodynamic advantage. Velomobiles for cargo use often have heavy frames to carry load, plus

10700-1005: The velomobile and rider, so a suspension can reduce the energy lost to bouncing. However, suspension adds cost, weight, and maintenance. Common velomobile designs include no suspension, front-only suspension, and front+rear suspension. As of 2017, there are several commercial makers of velomobiles. At the same time, there are still many "one-off" makers. Individual designs (both one-off and production) emphasize specific features. For example, some emphasize aerodynamics and light weight to improve average speed, even if cost, ease of entry/exit, comfort, and other "practical vehicle" attributes are reduced. By analogy, many automobile makers make performance cars with limited seating and cargo and worse emissions and fuel economy. In contrast, other velomobile designs sacrifice performance features in order to improve cost, entry/exit, comfort, carrying capacity, and so on. By analogy, many automobile makers offer cargo vans. As of 2017, individual makers sometimes offer models spanning

10807-461: The weight of the cargo itself. In turn, the weight of the fairing may be relatively less important. Also, bulky loads often have poor aerodynamics, and so the quality of aerodynamics of the fairing is less important. This may enable use of a fairing which in hot weather can be converted to a canopy. A canopy provides no aerodynamic benefits, but improves cooling compared to a faired configuration, while also reducing sun exposure compared to riding without

10914-408: The wings and the fuselage. When complete, a plane is rigorously inspected to search for imperfections and defects. After approval by inspectors, the plane is put through a series of flight tests to assure that all systems are working correctly and that the plane handles properly. To meet a particular customer need, the airplane may be customised using components or packages of components provided by

11021-477: The word airplane , like aeroplane , derives from the French aéroplane , which comes from the Greek ἀήρ ( aēr ), "air" and either Latin planus , "level", or Greek πλάνος ( planos ), "wandering". " Aéroplane " originally referred just to the wing, as it is a plane moving through the air. In an example of synecdoche , the word for the wing came to refer to the entire aircraft. In the United States and Canada,

11128-409: Was reputed to have designed and built the first artificial, self-propelled flying device, a bird-shaped model propelled by a jet of what was probably steam, said to have flown some 200 m (660 ft). This machine may have been suspended for its flight. Some of the earliest recorded attempts with gliders were those by the 9th-century Andalusian and Arabic-language poet Abbas ibn Firnas and

11235-519: Was tested with overhead rails to prevent it from rising. The test showed that it had enough lift to take off. The craft was uncontrollable and it is presumed that Maxim realized this because he subsequently abandoned work on it. Between 1867 and 1896, the German pioneer of human aviation Otto Lilienthal developed heavier-than-air flight. He was the first person to make well-documented, repeated, successful gliding flights. Lilienthal's work led to him developing

11342-526: Was the German Heinkel He 178 , which was tested in 1939. In 1943, the Messerschmitt Me 262 , the first operational jet fighter aircraft, went into service in the German Luftwaffe . The first jet airliner , the de Havilland Comet , was introduced in 1952. The Boeing 707 , the first widely successful commercial jet, was in commercial service for more than 50 years, from 1958 to 2010. The Boeing 747

11449-518: Was the world's biggest passenger aircraft from 1970 until it was surpassed by the Airbus A380 in 2005. Supersonic airliner flights , including those of the Concorde , have been limited to over-water flight at supersonic speed because of their sonic boom , which is prohibited over most populated land areas. The high cost of operation per passenger-mile and a deadly crash in 2000 induced the operators of

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