A prototype is an early sample, model, or release of a product built to test a concept or process. It is a term used in a variety of contexts, including semantics , design , electronics , and software programming . A prototype is generally used to evaluate a new design to enhance precision by system analysts and users. Prototyping serves to provide specifications for a real, working system rather than a theoretical one. Physical prototyping has a long history, and paper prototyping and virtual prototyping now extensively complement it. In some design workflow models, creating a prototype (a process sometimes called materialization ) is the step between the formalization and the evaluation of an idea.
90-841: The Northrop YA-9 is a prototype attack aircraft developed for the United States Air Force A-X program. The YA-9 was passed over in preference for the Fairchild Republic YA-10 that entered production as the A-10 Thunderbolt II . Criticism that the U.S. Air Force did not take close air support seriously prompted a few service members to seek a specialized attack aircraft. In the Vietnam War , large numbers of ground-attack aircraft were shot down by small arms , surface-to-air missiles , and low-level anti-aircraft gunfire, prompting
180-489: A C-8 Buffalo airframe as part of the NASA- Boeing joint Quiet Short-haul Research Aircraft (QSRA) study into a quiet short-haul commercial aircraft. Data from Airdata File: Northrop A-9A General characteristics Performance Armament Aircraft of comparable role, configuration, and era Related lists Prototype A prototype can also mean a typical example of something such as in
270-411: A coordinated turn , adverse yaw is effectively compensated by the use of the rudder , which results in a sideforce on the vertical tail that opposes the adverse yaw by creating a favorable yawing moment. Another method of compensation is ' differential ailerons ', which have been rigged so that the down-going aileron deflects less than the up-going one. In this case the opposing yaw moment is generated by
360-639: A mockup , which is an inert representation of a machine's appearance, often made of some non-durable substance. An electronics designer often builds the first prototype from breadboard or stripboard or perfboard , typically using "DIP" packages. However, more and more often the first functional prototype is built on a "prototype PCB " almost identical to the production PCB, as PCB manufacturing prices fall and as many components are not available in DIP packages, but only available in SMT packages optimized for placing on
450-472: A patent pool effectively putting an end to the Wright brothers patent war . The Wright company quietly changed its aircraft flight controls from wing warping to the use of ailerons at that time as well. Others who were previously thought to have been the first to introduce ailerons included: The Wright Brothers' Ohio patent attorney Henry Toulmin filed an expansive patent application and on May 22, 1906,
540-548: A second (thus defining the speed of light to be 299,792,458 meters per second). In many sciences, from pathology to taxonomy, prototype refers to a disease, species, etc. which sets a good example for the whole category. In biology, prototype is the ancestral or primitive form of a species or other group; an archetype. For example, the Senegal bichir is regarded as the prototypes of its genus, Polypterus . Aileron An aileron (French for "little wing" or "fin")
630-480: A Boulton-style pendulum controlled single-axis autopilot device. The pioneering U.S. aeronautical engineer Octave Chanute published descriptions and drawings of the Wright brothers ' 1902 glider in the leading aviation periodical of the day, L'Aérophile , in 1903. This prompted Esnault-Pelterie, a French military engineer, to build a Wright-style glider in 1904 that used ailerons in lieu of wing warping . The French journal L'Aérophile then published photos of
720-425: A PCB. Builders of military machines and aviation prefer the terms "experimental" and "service test". In electronics , prototyping means building an actual circuit to a theoretical design to verify that it works, and to provide a physical platform for debugging it if it does not. The prototype is often constructed using techniques such as wire wrapping or using a breadboard , stripboard or perfboard , with
810-410: A difference in profile drag between the left and right wingtips. Frise ailerons accentuate this profile drag imbalance by protruding beneath the wing of an upward-deflected aileron, most often by being hinged slightly behind the leading edge and near the bottom of the surface, with the lower section of the aileron surface's leading edge protruding slightly below the wing's undersurface when the aileron
900-529: A favorite among US Military modelers), railroad equipment, motor trucks, motorcycles, and space-ships (real-world such as Apollo/Saturn Vs, or the ISS). As of 2014, basic rapid prototype machines (such as 3D printers ) cost about $ 2,000, but larger and more precise machines can cost as much as $ 500,000. In architecture , prototyping refers to either architectural model making (as form of scale modelling ) or as part of aesthetic or material experimentation , such as
990-619: A former curator of the Smithsonian Air & Space Museum in Washington, D.C., and other researchers, due to the patent they had received the Wrights stood firmly on the position that all flying using lateral roll control, anywhere in the world, would only be conducted under license by them. The Wrights subsequently became embroiled with numerous lawsuits they launched against aircraft builders who used lateral flight controls, and
SECTION 10
#17327767179991080-448: A legal resolution. A much earlier aileron concept was patented in 1868 by British scientist Matthew Piers Watt Boulton , based on his 1864 paper On Aërial Locomotion . The name "aileron", from French, meaning "little wing", also refers to the extremities of a bird's wings used to control their flight. It first appeared in print in the 7th edition of Cassell's French-English Dictionary of 1877, with its lead meaning of "small wing". In
1170-539: A maximum flyaway cost of $ 1.4 million based on a 600 aircraft production run. Performance was to be sacrificed where necessary to keep development and production costs under control. During this time, a separate RFP was released for A-X's 30 mm cannon with requirements for a high rate of fire (4,000 round/minute) and a high muzzle velocity. Six companies submitted proposals to the USAF, with Northrop and Fairchild Republic selected on 18 December 1970 to build prototypes:
1260-499: A time to the initial prototype. In many programming languages , a function prototype is the declaration of a subroutine or function (and should not be confused with software prototyping). This term is rather C / C++ -specific; other terms for this notion are signature , type and interface . In prototype-based programming (a form of object-oriented programming ), new objects are produced by cloning existing objects, which are called prototypes. The term may also refer to
1350-472: A way that the Planck constant h is prescribed a value of exactly 6.626 070 15 × 10 joule-second (J⋅s) Until 1960, the meter was defined by a platinum-iridium prototype bar with two marks on it (that were, by definition, spaced apart by one meter), the international prototype of the metre , and in 1983 the meter was redefined to be the distance in free space covered by light in 1/299,792,458 of
1440-518: Is a form of functional or working prototype. The justification for its creation is usually a data migration , data integration or application implementation project and the raw materials used as input are an instance of all the relevant data which exists at the start of the project. The objectives of data prototyping are to produce: To achieve this, a data architect uses a graphical interface to interactively develop and execute transformation and cleansing rules using raw data. The resultant data
1530-444: Is a hinged flight control surface usually forming part of the trailing edge of each wing of a fixed-wing aircraft . Ailerons are used in pairs to control the aircraft in roll (or movement around the aircraft's longitudinal axis ), which normally results in a change in flight path due to the tilting of the lift vector . Movement around this axis is called 'rolling' or 'banking'. Considerable controversy exists over credit for
1620-502: Is basically countered by aircraft yaw stability and also by the use of differential aileron movement. The Frise-type aileron also forms a slot, so air flows smoothly over the lowered aileron, making it more effective at high angles of attack. Frise-type ailerons may also be designed to function differentially. Like the differential aileron , the Frise-type aileron does not eliminate adverse yaw entirely. Coordinated rudder application
1710-517: Is becoming practical to eliminate the creation of a physical prototype (except possibly at greatly reduced scales for promotional purposes), instead modeling all aspects of the final product as a computer model . An example of such a development can be seen in Boeing 787 Dreamliner , in which the first full sized physical realization is made on the series production line. Computer modeling is now being extensively used in automotive design, both for form (in
1800-411: Is caused partly by the change in drag between the left and right wing. The rising wing generates increased lift, which causes increased induced drag . The descending wing generates reduced lift, which causes reduced induced drag. Profile drag caused by the deflected ailerons may add further to the difference, along with changes in the lift vectors as one rotates back while the other rotates forward. In
1890-431: Is deflected upwards, substantially increasing profile drag on that side. Ailerons may also be designed to use a combination of these methods. With ailerons in the neutral position, the wing on the outside of the turn develops more lift than the opposite wing due to the variation in airspeed across the wing span, which tends to cause the aircraft to continue to roll. Once the desired angle of bank (degree of rotation about
SECTION 20
#17327767179991980-402: Is moved downward, the other is moved upward: the down-going aileron increases the lift on its wing while the up-going aileron reduces the lift on its wing, producing a rolling (also called 'banking') moment about the aircraft's longitudinal axis (which extends from the nose to the tail of an airplane). Ailerons are usually situated near the wing tip , but may sometimes also be situated nearer
2070-412: Is still needed when ailerons are applied. By careful design of the mechanical linkages, the up aileron can be made to deflect more than the down aileron (e.g., US patent 1,565,097). This helps reduce the likelihood of a wing tip stall when aileron deflections are made at high angles of attack. In addition, the consequent differential in drag reduces adverse yaw (as also discussed above ). The idea
2160-422: Is that the loss of lift associated with the up aileron carries no penalty while the increase in lift associated with the down aileron is minimized. The rolling couple on the aircraft is always the difference in lift between the two wings. A designer at de Havilland invented a simple and practical linkage and their de Havilland Tiger Moth classic British biplane became one of the best-known aircraft, and one of
2250-414: Is then evaluated and the rules refined. Beyond the obvious visual checking of the data on-screen by the data architect, the usual evaluation and validation approaches are to use Data profiling software and then to insert the resultant data into a test version of the target application and trial its use. When developing software or digital tools that humans interact with, a prototype is an artifact that
2340-499: Is used as the standard of measurement of some physical quantity to base all measurement of that physical quantity against. Sometimes this standard object is called an artifact . In the International System of Units ( SI ), there remains no prototype standard since May 20, 2019 . Before that date, the last prototype used was the international prototype of the kilogram , a solid platinum-iridium cylinder kept at
2430-409: Is used to ask and answer a design question. Prototypes provide the means for examining design problems and evaluating solutions. HCI practitioners can employ several different types of prototypes: In the field of scale modeling (which includes model railroading , vehicle modeling, airplane modeling , military modeling, etc.), a prototype is the real-world basis or source for a scale model—such as
2520-493: The Bristol Aeroplane Company developed an aileron shape that is pivoted at about its 25 to 30% chord line and near its bottom surface [1] , in order to decrease stick forces as aircraft became faster during the 1930s. When the aileron is deflected up (to make its wing go down), the leading edge of the aileron starts to protrude below the underside of the wing into the airflow beneath the wing. The moment of
2610-594: The Bureau International des Poids et Mesures (International Bureau of Weights and Measures) in Sèvres France (a suburb of Paris ) that by definition was the mass of exactly one kilogram . Copies of this prototype are fashioned and issued to many nations to represent the national standard of the kilogram and are periodically compared to the Paris prototype. Now the kilogram is redefined in such
2700-528: The Forty Wall House open source material prototyping centre in Australia. Architects prototype to test ideas structurally, aesthetically and technically. Whether the prototype works or not is not the primary focus: architectural prototyping is the revelatory process through which the architect gains insight. In the science and practice of metrology , a prototype is a human-made object that
2790-536: The Prototype Javascript Framework . Additionally, the term may refer to the prototype design pattern. Continuous learning approaches within organizations or businesses may also use the concept of business or process prototypes through software models. The concept of prototypicality is used to describe how much a website deviates from the expected norm, and leads to a lowering of user preference for that site's design. A data prototype
Northrop YA-9 - Misplaced Pages Continue
2880-473: The fuselage is parallel to the flight path. A simple gauge on the instrument panel called the slip indicator , also known as "the ball", indicates when this coordination is achieved. Particularly on larger or faster aircraft, control forces may be extremely heavy. Borrowing a discovery from boats that extending a control surface's area forward of the hinge lightens the forces needed first appeared on ailerons during World War I when ailerons were extended beyond
2970-501: The later version of the Santos-Dumont Demoiselle , which only warped the wingtips "downward". One of the disadvantages of this setup was a greater tendency to yaw than even with basic interconnected ailerons. During the 1930s a number of light aircraft used single acting controls but used springs to return the ailerons to their neutral positions when the stick was released. Used on the first-ever airframe to have
3060-421: The styling and aerodynamics of the vehicle) and in function—especially for improving vehicle crashworthiness and in weight reduction to improve mileage. The most common use of the word prototype is a functional, although experimental, version of a non-military machine (e.g., automobiles, domestic appliances, consumer electronics) whose designers would like to have built by mass production means, as opposed to
3150-427: The wing root . Modern airliners may also have a second pair of ailerons on their wings, with the two positions distinguished by the terms 'outboard aileron' and 'inboard aileron'. An unwanted side effect of aileron operation is adverse yaw —a yawing moment in the opposite direction to the roll. Using the ailerons to roll an aircraft to the right produces a yawing motion to the left. As the aircraft rolls, adverse yaw
3240-603: The 1938 popular US Piper J-3 Cub monoplane possessed Frise ailerons as designed and helped introduce them to a wide audience. A claimed benefit of the Frise aileron is the ability to counteract adverse yaw. To do so, the leading edge of the aileron has to be sharp or bluntly rounded, which adds significant drag to the upturned aileron and helps counterbalance the yaw force created by the other aileron turned down. This can add some unpleasant, nonlinear effect and/or potentially dangerous aerodynamic vibration (flutter). Adverse yaw moment
3330-617: The Air Force released a request for information to 21 defense contractors for the A-X. The objective was to create a design study for a low-cost attack aircraft. Discussions with A-1 Skyraider pilots operating in Vietnam and analysis of the effectiveness of current aircraft used in the role indicated the ideal aircraft should have long loiter time, low-speed maneuverability, massive cannon firepower, and extreme survivability; an aircraft that had
3420-603: The Cessna 152/172 series can be roll controlled with rudder alone. The rudder of the Boeing 737 has more roll authority over the aircraft than the ailerons at high angles of attack. This led to two notable accidents when the rudder jammed in the fully deflected position causing rollovers (see Boeing 737 rudder issues ). Some aircraft such as the Fokker Spin and model gliders lack any type of lateral control. Those aircraft use
3510-641: The Junkers J 7 all-duralumin metal demonstrator monoplane using them—the J 7 led directly to the Junkers D.I all-duralumin metal German fighter design of 1918, which had conventionally hinged ailerons. The main problem with this type of aileron is the dangerous tendency to stall if used aggressively, especially if the aircraft is already in danger of stalling, hence the use primarily on prototypes, and their replacement on production aircraft with more conventional ailerons. Engineer Leslie George Frise (1897–1979) of
3600-545: The Wrights. There are still conflicting claims today over who first invented the aileron. Other 19th century engineers and scientists, including Charles Renard , Alphonse Pénaud , and Louis Mouillard , had described similar flight control surfaces. Another technique for lateral flight control, wing warping , was also described or experimented with by several people including Jean-Marie Le Bris , John Montgomery , Clement Ader , Edson Gallaudet , D.D. Wells, and Hugo Mattullath. Aviation historian C.H. Gibbs-Smith wrote that
3690-824: The YA-9 rather than the more powerful (9,280 lbf (41.3 kN)) General Electric TF34 used by the A-10, although either engine could be accommodated. The YF102 engine was a new design, based on the Avco Lycoming T55 turboshaft that powered the Boeing CH-47 Chinook helicopter, which was selected in order to minimize costs. The aircraft had a large cruciform stabilizer in order to improve directional stability for low-level flight. Split ailerons were fitted that could be used as airbrakes . When these airbrakes were operated asymmetrically in conjunction with
Northrop YA-9 - Misplaced Pages Continue
3780-501: The YA-9A and YA-10A, respectively. Meanwhile, General Electric and Philco-Ford were selected to build and test GAU-8 cannon prototypes. The A-9 was a shoulder-wing monoplane of all-riveted aluminum alloy construction, with honeycomb structures and chemically milled skins. The required twin turbofans were fitted in nacelles under the aircraft's wing roots. Northrop selected the 7,200 lbf (32 kN) Lycoming YF102 engine for
3870-438: The advantage of not weakening the airplane's wing structure as did the wing warping technique, which was one reason for Esnault-Pelterie's decision to switch to ailerons. By 1911 most biplanes used ailerons rather than wing warping—by 1915 ailerons had become almost universal on monoplanes as well. The U.S. Government, frustrated by the lack of its country's aeronautical advances in the years leading up to World War I , enforced
3960-418: The aileron lower surface, ahead of the aileron hinge, by a lever arm. They reduce the force needed by the pilot to deflect the aileron and are often seen on aerobatic aircraft. As the aileron is deflected upward, the spade produces a downward aerodynamic force, which tends to rotate the whole assembly so as to further deflect the aileron upward. The size of the spade (and its lever arm) determines how much force
4050-558: The aileron was "....one of the most remarkable inventions... of aeronautical history, which was immediately lost sight of". In 1906 the Wright brothers obtained a patent not for the invention of an airplane (which had existed for a number of decades in the form of gliders) but for the invention of a system of aerodynamic control that manipulated a flying machine's surfaces, including lateral flight control, although rudders , elevators and ailerons had previously been invented. Pairs of ailerons are typically interconnected so that when one
4140-405: The aileron. In addition to reducing the risk of flutter, mass balances also reduce the stick forces required to move the control surface in maneuvers. Some aileron designs, particularly when fitted on swept wings, include fences like wing fences flush with their inboard plane, in order to suppress some of the spanwise component of the airflow running on the top of the wing, which tends to disrupt
4230-424: The aileron. In some aircraft the aileron construction may be too heavy to allow this system to work without an excessive increase in the weight of the aileron. In this case, the weight may be added to a lever arm to move the weight well out in front to the aileron body. These balance weights are tear drop shaped (to reduce drag), which make them appear quite different from spades, although both project forward and below
4320-629: The ailerons on Esnault-Pelterie's glider which were included in his June 1905 article, and its ailerons were widely copied afterward. The Wright brothers used wing warping instead of ailerons for roll control on their glider in 1902, and about 1904 their Flyer II was the only aircraft of its time able to do a coordinated banked turn. During the early years of powered flight the Wrights had better roll control on their designs than airplanes that used movable surfaces. From 1908, as aileron designs were refined it became clear that ailerons were much more effective and practical than wing warping. Ailerons also had
4410-473: The aircraft's rudder , sideways control forces could be applied (and the aircraft moved sideways) without yawing or banking , easing weapon aiming. The pilot sat under a large bubble canopy well ahead of the leading edge of the wings. The cockpit was surrounded by a bathtub of armor (aluminum in the prototypes, which would have been replaced by titanium if production occurred) while the wing-mounted fuel tanks were self-sealing and filled with foam to minimize
4500-531: The airflow over a wing, disrupt the airflow and reduce the amount of lift generated. Many modern aircraft designs, especially jet aircraft , use spoilers in lieu of, or to supplement ailerons, such as the F4 Phantom II and Northrop P-61 Black Widow , which had almost full width flaps (there were very small conventional ailerons at the wingtips as well). All aircraft with dihedral have some form of yaw-roll coupling to promote stability. Common trainers like
4590-483: The best elements of the Ilyushin Il-2 , Henschel Hs 129 and Skyraider. While turboprop engines were requested in the initial request, by May 1969, requirements had changed to specify use of turbofan engines. In May 1970, the USAF issued a modified, and much more detailed request for proposals (RFP). The threat of Soviet armored forces and all-weather attack operations had become more serious. Now included in
SECTION 50
#17327767179994680-513: The brothers were consequently blamed for playing "...a major role in the lack of growth and aviation industry competition in the United States comparative to other nations like Germany leading up to and during World War I". Years of protracted legal conflict ensued with many other aircraft builders until the U.S. entered World War I, when the government imposed a legislated agreement among the parties which resulted in royalty payments of 1% to
4770-416: The brothers were granted U.S. Patent 821393. The patent's importance lay in its claim of a new and useful method of controlling an airplane. The patent application included the claim for the lateral control of aircraft flight that was not limited to wing warping, but through any manipulation of the "....angular relations of the lateral margins of the airplanes [wings].... varied in opposite directions". Thus
4860-488: The cockpit so that different power settings or flight attitudes can be compensated for. Some large aircraft from the 1950s (including the Canadair Argus ) used free floating control surfaces that the pilot controlled only through the deflection of trim tabs, in which case additional tabs were also provided to fine-tune the control to provide straight and level flight. Spades are flat metal plates, usually attached to
4950-541: The combination of "joystick/rudder-bar" controls that directly led to the modern flight control system , the Blériot VIII in 1908, some designs of early aircraft used "wingtip" ailerons, where the entire wingtip was rotated to achieve roll control as a separate, pivoting roll-control surface—the AEA June Bug used a form of these, with both the experimental German Fokker V.1 of 1916 and the earlier versions of
5040-614: The context of powered airplanes it appears in print about 1908. Prior to that, ailerons were often referred to as rudders , their older technical sibling, with no distinction between their orientations and functions, or more descriptively as horizontal rudders (in French, gouvernails horizontaux ). Among the earliest printed aeronautical use of 'aileron' was that in the French aviation journal L'Aérophile of 1908. Ailerons had more or less completely supplanted other forms of lateral control, such as wing warping , by about 1915, well after
5130-407: The cycle returns to customer evaluation. The cycle starts by listening to the user, followed by building or revising a mock-up, and letting the user test the mock-up , then back. There is now a new generation of tools called Application Simulation Software which help quickly simulate application before their development. Extreme programming uses iterative design to gradually add one feature at
5220-602: The development of an aircraft better able to survive such weapons. Fast jets such as the North American F-100 Super Sabre , Republic F-105 Thunderchief , and McDonnell Douglas F-4 Phantom II proved for the most part to be ineffective for close air support. The Douglas A-1 Skyraider was the USAF's primary close air support aircraft. In mid-1966, the U.S. Air Force formed the Attack Experimental (A-X) program office. On 6 March 1967,
5310-542: The earliest, to use differential ailerons. On the earliest Pioneer Era aircraft, such as the Wright Flyer and the later, 1909-origin Blériot XI and Etrich Taube , lateral control was effected by twisting the outboard portion of the wing so as to increase or decrease lift by changing the angle of attack. This had the disadvantages of stressing the structure, being heavy on the controls, and of risking stalling
5400-527: The established TF34 engine by the YA-10 rather than the untried F102 may have been preferred by the Air Force, while Fairchild had no alternative work available and was unlikely to survive if it did not win the A-X contract. The two YA-9 prototypes were subsequently relegated to NASA for continued flight testing before being retired. When retired, the YA-9s' custom-built engines were removed and were later mated to
5490-480: The final production costs due to inefficiencies in materials and processes. Prototypes are also used to revise the design for the purposes of reducing costs through optimization and refinement. It is possible to use prototype testing to reduce the risk that a design may not perform as intended, however prototypes generally cannot eliminate all risk. Building the full design is often expensive and can be time-consuming, especially when repeated several times—building
SECTION 60
#17327767179995580-528: The final production design. This is due to the skill and choices of the designer(s), and the inevitable inherent limitations of a prototype. Due to differences in materials, processes and design fidelity, it is possible that a prototype may fail to perform acceptably although the production design may have been sound. Conversely, prototypes may perform acceptably but the production design and outcome may prove unsuccessful. In general, it can be expected that individual prototype costs will be substantially greater than
5670-464: The full design, figuring out what the problems are and how to solve them, then building another full design. As an alternative, rapid prototyping or rapid application development techniques are used for the initial prototypes, which implement part, but not all, of the complete design. This allows designers and manufacturers to rapidly and inexpensively test the parts of the design that are most likely to have problems, solve those problems, and then build
5760-508: The full design. In technology research, a technology demonstrator is a prototype serving as proof-of-concept and demonstration model for a new technology or future product, proving its viability and illustrating conceivable applications. In large development projects, a testbed is a platform and prototype development environment for rigorous experimentation and testing of new technologies, components, scientific theories and computational tools. With recent advances in computer modeling it
5850-454: The function of the rudder and elevator flight controls had been largely standardised. Although there were previously many conflicting claims over who first invented the aileron and its function, i.e., lateral or roll control, the flight control device was invented and described by the British scientist and metaphysicist Matthew Piers Watt Boulton in his 1864 paper On Aërial Locomotion . He
5940-475: The impact of these differences on the intended role for the prototype. For example, if a visual prototype is not able to use the same materials as the final product, they will attempt to substitute materials with properties that closely simulate the intended final materials. Engineers and prototyping specialists seek to understand the limitations of prototypes to exactly simulate the characteristics of their intended design. Prototypes represent some compromise from
6030-522: The invention of the aileron. The Wright brothers and Glenn Curtiss fought a years-long legal battle over the Wright patent of 1906, which described a method of wing-warping to achieve lateral control. The brothers prevailed in several court decisions which found that Curtiss's use of ailerons violated the Wright patent. Ultimately, the First World War compelled the U.S. Government to legislate
6120-632: The laminar flow above the aileron, when deflected downwards. Used during aviation's pre-war "pioneer era" and into the early years of the First World War, these ailerons were each controlled by a single cable, which pulled the aileron up. When the aircraft was at rest, the ailerons hung vertically down. This type of aileron was used on the Farman III biplane 1909 and the Short 166 . A "reverse" version of this, utilizing wing-warping, existed on
6210-462: The lateral control of flying machines. The fact that the Wright brothers were able to gain a patent in 1906 did not invalidate Boulton's lost and forgotten invention. Ailerons were not used on manned aircraft until they were employed on Robert Esnault-Pelterie 's glider in 1904, although in 1871 a French military engineer, Charles Renard , built and flew an unmanned glider incorporating ailerons on each side (which he termed 'winglets'), activated by
6300-512: The leading edge in the airflow helps to move up the trailing edge, which decreases the stick force. The down moving aileron also adds energy to the boundary layer. The edge of the aileron directs air flow from the underside of the wing to the upper surface of the aileron, thus creating a lifting force added to the lift of the wing. This reduces the needed deflection of the aileron. Both the Canadian Fleet Model 2 biplane of 1930 and
6390-401: The longitudinal axis) has been obtained, the pilot uses opposite aileron to prevent the angle of bank from increasing due to this variation in lift across the wing span. This minor opposite use of the control must be maintained throughout the turn. The pilot also uses a slight amount of rudder in the same direction as the turn to counteract adverse yaw and to produce a "coordinated" turn wherein
6480-579: The nose. As the gun was mounted on the aircraft's centerline, the undercarriage nosewheel was offset one foot (0.30 m) to the left. As the GAU-8 Avenger cannon was not ready, both YA-9 prototypes (and the two YA-10s) were fitted with the smaller 20 mm M61 Vulcan instead. Ten underwing hardpoints were fitted, allowing up to 16,000 lb (7,300 kg) of weapons, including bombs and AGM-65 Maverick air-to-ground missiles , to be carried. The YA-9 took its first flight on 30 May 1972, with
6570-481: The patent explicitly stated that other methods besides wing-warping could be used for adjusting the outer portions of an airplane's wings to different angles on its right and left sides to achieve lateral roll control. John J. Montgomery was granted U.S. Patent 831173 at nearly the same time for his methods of wing warping. Both the Wright Brothers patent and Montgomery's patent were reviewed and approved by
6660-404: The pilot needs to apply to deflect the aileron. A spade works in the same manner as a horn but is more efficient due to the longer moment arm . To increase the speed at which control surface flutter ( aeroelastic flutter ) might become a risk, the center of gravity of the control surface is moved towards the hinge-line for that surface. To achieve this, lead weights may be added to the front of
6750-473: The potential for fires or massive fuel loss. Dual redundant hydraulic flight control systems were fitted, with a further manual backup to prevent a single hit from causing control failure. These design features were hoped to reduce combat losses by as much as 90% in Vietnam-type operations. A single 30 mm rotary cannon was to be fitted in the belly of the aircraft, with the gun barrels extending under
6840-411: The prototyping platform, or replace it with only the microcontroller chip and the circuitry that is relevant to their product. Prototype software is often referred to as alpha grade , meaning it is the first version to run. Often only a few functions are implemented, the primary focus of the alpha is to have a functional base code on to which features may be added. Once alpha grade software has most of
6930-438: The real EMD GP38-2 locomotive—which is the prototype of Athearn 's (among other manufacturers) locomotive model. Technically, any non-living object can serve as a prototype for a model, including structures, equipment, and appliances, and so on, but generally prototypes have come to mean full-size real-world vehicles including automobiles (the prototype 1957 Chevy has spawned many models), military equipment (such as M4 Shermans,
7020-463: The required features integrated into it, it becomes beta software for testing of the entire software and to adjust the program to respond correctly during situations unforeseen during development. Often the end users may not be able to provide a complete set of application objectives, detailed input, processing, or output requirements in the initial stage. After the user evaluation, another prototype will be built based on feedback from users, and again
7110-416: The requirements was that the aircraft would be designed specifically for the 30 mm cannon. The RFP also called for an aircraft with a maximum speed of 460 mph (740 km/h), takeoff distance of 4,000 feet (1,200 m), external load of 16,000 pounds (7,300 kg), 285-mile (460 km) mission radius, and a unit cost of US$ 1.4 million. Simplicity and low cost were also vital requirements, with
7200-459: The result being a circuit that is electrically identical to the design but not physically identical to the final product. Open-source tools like Fritzing exist to document electronic prototypes (especially the breadboard-based ones) and move toward physical production. Prototyping platforms such as Arduino also simplify the task of programming and interacting with a microcontroller . The developer can choose to deploy their invention as-is using
7290-410: The same benefit. Trim tabs are small movable sections resembling scaled down ailerons located at or near the trailing edge of the aileron. On most propeller powered aircraft, the rotation of the propeller(s) induces a counteracting roll movement due to Newton's third law of motion , in that every action has an equal and opposite reaction. To relieve the pilot of having to provide continuous pressure on
7380-566: The same patent examiner at the United States Patent Office, William Townsend. At the time Townsend indicated that both methods of wing warping were invented independently and were sufficiently different to each justify their own patent award. Multiple U.S. court decisions favoured the expansive Wright patent, which the Wright Brothers sought to enforce with licensing fees starting from $ 1,000 per airplane, and said to range up to $ 1,000 per day. According to Louis S. Casey,
7470-400: The second prototype flying on 23 August. Northrop's flight testing was successful, with the aircraft claimed to have "fighter-like" handling and to be a good weapon platform. A fly-off by USAF test pilots of the two competing designs took place between 10 October and 9 December 1972. While the YA-9 fully met the USAF's requirements, the YA-10 was declared the winner on 18 January 1973. The use of
7560-493: The sense of a mark left by a blow, then by a stamp struck by a die (note "typewriter"); by implication a scar or mark; by analogy a shape i.e. a statue, (figuratively) style, or resemblance; a model for imitation or illustrative example—note "typical"). Prototypes explore different aspects of an intended design: In general, the creation of prototypes will differ from creation of the final product in some fundamental ways: Engineers and prototype specialists attempt to minimize
7650-663: The side with the increased angle of attack during a maneuver. By 1916, most designers had abandoned wing warping in favor of ailerons. Researchers at NASA and elsewhere have been taking a second look at wing warping again, although under new names. The NASA version is the X-53 Active Aeroelastic Wing while the United States Air Force tested the Adaptive Compliant Wing . Spoilers are devices that when extended into
7740-441: The stick in one direction (which causes fatigue) trim tabs are provided to adjust or trim out the pressure needed against any unwanted movement. The tab itself is deflected in relation to the aileron, causing the aileron to move in the opposite direction. Trim tabs come in two forms, adjustable and fixed. A fixed trim tab is manually bent to the required amount of deflection, while the adjustable trim tab can be controlled from within
7830-513: The use of the derivation ' prototypical '. This is a useful term in identifying objects, behaviours and concepts which are considered the accepted norm and is analogous with terms such as stereotypes and archetypes . The word prototype derives from the Greek πρωτότυπον prototypon , "primitive form", neutral of πρωτότυπος prototypos , "original, primitive", from πρῶτος protos , "first" and τύπος typos , "impression" (originally in
7920-473: The wingtip and provided with a horn ahead of the hinge. Known as overhung ailerons, possibly the best known examples are the Handley Page Type O (first flight 17 December 1915), Sopwith Snipe , Fokker Dr.I and Fokker D.VII . Later examples brought the counterbalance in line with the wing to improve control and reduce drag. This is seen less often now, due to the Frise type aileron which provides
8010-559: Was also endorsed by C.H. Gibbs-Smith. Boulton's British patent, No. 392 of 1868, issued about 35 years before ailerons were "reinvented" in France, became forgotten and lost from sight until after the flight control device was in general use. Gibbs-Smith stated on several occasions that if the Boulton patent had been revealed at the time of the Wright brothers ' legal filings, they might not have been able to claim priority of invention for
8100-419: Was the first to patent an aileron control system in 1868. Boulton's description of his lateral flight control system was "the first record we have of appreciation of the necessity for active lateral control as distinguished from [passive lateral stability].... With this invention of Boulton's we have the birth of the present-day three torque method of airborne control" as was praised by Charles Manly . This
#998001