Aerodynamics ( Ancient Greek : ἀήρ aero (air) + Ancient Greek : δυναμική (dynamics)) is the study of the motion of air , particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dynamics and its subfield of gas dynamics , and is an important domain of study in aeronautics . The term aerodynamics is often used synonymously with gas dynamics, the difference being that "gas dynamics" applies to the study of the motion of all gases, and is not limited to air. The formal study of aerodynamics began in the modern sense in the eighteenth century, although observations of fundamental concepts such as aerodynamic drag were recorded much earlier. Most of the early efforts in aerodynamics were directed toward achieving heavier-than-air flight , which was first demonstrated by Otto Lilienthal in 1891. Since then, the use of aerodynamics through mathematical analysis, empirical approximations, wind tunnel experimentation, and computer simulations has formed a rational basis for the development of heavier-than-air flight and a number of other technologies. Recent work in aerodynamics has focused on issues related to compressible flow , turbulence , and boundary layers and has become increasingly computational in nature.
79-570: The Gloster VI was a racing seaplane developed as a contestant for the 1929 Schneider Trophy by the Gloster Aircraft Company . The aircraft was known as the Golden Arrow , partly in reference to its colour, the distinctive three-lobed cowling of the 'broad-arrow' Napier Lion engine, but also to another contemporary Lion-powered record-breaker, Henry Segrave 's Golden Arrow land speed record car. The Gloster VI
158-574: A Savoia S.51 . The 1923 trophy, contested at Cowes , went to the Americans with a sleek, liquid-cooled engined craft designed by Glenn Curtiss . It used the Curtiss D-12 engine. US Navy Lieutenant David Rittenhouse won the cup, and his teammate Rutledge Irvine was second in an identical aircraft. The British Sea Lion III (flown by 1922 winner Henry Biard), and the French entry withdrew from
237-463: A Sopwith Tabloid flown by Howard Pixton at 139.74 km/h (86.83 mph); the 1914 race was contested by three nations: France, the United Kingdom, and Switzerland. The United States and Germany failed to qualify. From 1915 to 1918, competition was suspended for the duration of World War I . After the war, the competition resumed in 1919 at Bournemouth where in foggy conditions
316-426: A shock wave . The presence of shock waves, along with the compressibility effects of high-flow velocity (see Reynolds number ) fluids, is the central difference between the supersonic and subsonic aerodynamics regimes. In aerodynamics, hypersonic speeds are speeds that are highly supersonic. In the 1970s, the term generally came to refer to speeds of Mach 5 (5 times the speed of sound) and above. The hypersonic regime
395-591: A BBC television documentary series; and in 1988, when it was a central part of that year's ITV Telethon Appeal. DEC invited customers and partners to each year's event as guests, and the general public watched in increasing numbers as the series grew in size and popularity. For the pilots taking part, the event became, along with the King's Cup air race , the highlight of the UK's air racing season, and regularly attracted entrants from continental Europe. DEC continued to sponsor
474-504: A broader commercial sponsorship programme designed to increase DEC's presence in the UK market at that time. DEC sponsored this revived race series from 1984 until 1991, which also marked the diamond jubilee of the final race in the original series. DEC and Infopress turned to the expertise of the Royal Aero Club's Records, Racing & Rally Association which again administered and ran the actual races. The 1981 Solent course, itself
553-467: A close approximation of the original 1929 and 1931 Schneider Trophy courses over the Solent, was also used and adapted from year to year. This sponsorship had a profound effect on the awareness and popularity of handicapped air racing in the UK and further afield, as well as markedly increasing DEC's commercial profile in the UK. The appeal of the race, its historic connections, and the fact that prize money
632-482: A continuum. Continuum flow fields are characterized by properties such as flow velocity , pressure , density , and temperature , which may be functions of position and time. These properties may be directly or indirectly measured in aerodynamics experiments or calculated starting with the equations for conservation of mass, momentum , and energy in air flows. Density, flow velocity, and an additional property, viscosity , are used to classify flow fields. Flow velocity
711-410: A flow field) enables the calculation of forces and moments acting on the object. In many aerodynamics problems, the forces of interest are the fundamental forces of flight: lift , drag , thrust , and weight . Of these, lift and drag are aerodynamic forces, i.e. forces due to air flow over a solid body. Calculation of these quantities is often founded upon the assumption that the flow field behaves as
790-438: A fluid, the speed of sound in that fluid can be considered the fastest speed that "information" can travel in the flow. This difference most obviously manifests itself in the case of a fluid striking an object. In front of that object, the fluid builds up a stagnation pressure as impact with the object brings the moving fluid to rest. In fluid traveling at subsonic speed, this pressure disturbance can propagate upstream, changing
869-414: A fundamental relationship between pressure, density, and flow velocity for incompressible flow known today as Bernoulli's principle , which provides one method for calculating aerodynamic lift. In 1757, Leonhard Euler published the more general Euler equations which could be applied to both compressible and incompressible flows. The Euler equations were extended to incorporate the effects of viscosity in
SECTION 10
#1732781096233948-750: A measured mile course for a top speed of 351.3 mph and a ratified world absolute speed record, averaged over four runs of 336.3 mph. This record was held only briefly, as a later run by Squadron Leader Augustus Orlebar in the S.6 managed to raise it over 350 mph. During the final Schneider Trophy in 1931, the Gloster VI was still in service with the High Speed Flight as a trainer. Data from General characteristics Performance Aircraft of comparable role, configuration, and era Schneider Trophy The Coupe d'Aviation Maritime Jacques Schneider , also known as
1027-492: A minimum of 100 hours as pilot-in-command, and a valid air racing licence. Following that event, the UK subsidiary of US computer company Digital Equipment Corporation (DEC) independently decided to sponsor a long-term revival of the Schneider Trophy, with the first race held in 1984, and races held annually, with a few omissions, since then. The idea was submitted by DEC's then UK PR consultancy Infopress as part of
1106-476: A new world speed record of 610 km/h (380 mph) and won the trophy outright with a third straight win. The following days saw the winning Supermarine S.6B further break the world speed record twice, making it the first craft to break the 400 mph barrier on 29 September at an average speed of 655.8 km/h (407.5 mph). Although the British team had secured the trophy for the UK permanently with
1185-410: A range of flow velocities just below and above the local speed of sound (generally taken as Mach 0.8–1.2). It is defined as the range of speeds between the critical Mach number , when some parts of the airflow over an aircraft become supersonic , and a higher speed, typically near Mach 1.2 , when all of the airflow is supersonic. Between these speeds, some of the airflow is supersonic, while some of
1264-448: A speed of 682.36 km/h (424.00 mph). Eighteen months later in the same venue, it broke the 700 km/h barrier with an average speed of 709.202 km/h (440.678 mph). Both times the plane was piloted by Francesco Agello . This speed remains the fastest speed ever attained by a piston-engined seaplane. For a complete list of the aircraft which competed in the competitions, see List of Schneider Trophy aircraft . In 1981
1343-418: Is a flow in which density is constant in both time and space. Although all real fluids are compressible, a flow is often approximated as incompressible if the effect of the density changes cause only small changes to the calculated results. This is more likely to be true when the flow speeds are significantly lower than the speed of sound. Effects of compressibility are more significant at speeds close to or above
1422-448: Is a solution in one dimension to both the momentum and energy conservation equations. The ideal gas law or another such equation of state is often used in conjunction with these equations to form a determined system that allows the solution for the unknown variables. Aerodynamic problems are classified by the flow environment or properties of the flow, including flow speed , compressibility , and viscosity . External aerodynamics
1501-416: Is a subset of the supersonic regime. Hypersonic flow is characterized by high temperature flow behind a shock wave, viscous interaction, and chemical dissociation of gas. The incompressible and compressible flow regimes produce many associated phenomena, such as boundary layers and turbulence. The concept of a boundary layer is important in many problems in aerodynamics. The viscosity and fluid friction in
1580-503: Is associated with the frictional forces in a flow. In some flow fields, viscous effects are very small, and approximate solutions may safely neglect viscous effects. These approximations are called inviscid flows. Flows for which viscosity is not neglected are called viscous flows. Finally, aerodynamic problems may also be classified by the flow environment. External aerodynamics is the study of flow around solid objects of various shapes (e.g. around an airplane wing), while internal aerodynamics
1659-407: Is called laminar flow . Aerodynamics is a significant element of vehicle design , including road cars and trucks where the main goal is to reduce the vehicle drag coefficient , and racing cars , where in addition to reducing drag the goal is also to increase the overall level of downforce . Aerodynamics is also important in the prediction of forces and moments acting on sailing vessels . It
SECTION 20
#17327810962331738-409: Is called potential flow and allows the differential equations that describe the flow to be a simplified version of the equations of fluid dynamics , thus making available to the aerodynamicist a range of quick and easy solutions. In solving a subsonic problem, one decision to be made by the aerodynamicist is whether to incorporate the effects of compressibility. Compressibility is a description of
1817-497: Is the study of flow around solid objects of various shapes. Evaluating the lift and drag on an airplane or the shock waves that form in front of the nose of a rocket are examples of external aerodynamics. Internal aerodynamics is the study of flow through passages in solid objects. For instance, internal aerodynamics encompasses the study of the airflow through a jet engine or through an air conditioning pipe. Aerodynamic problems can also be classified according to whether
1896-415: Is the study of flow through passages inside solid objects (e.g. through a jet engine). Unlike liquids and solids, gases are composed of discrete molecules which occupy only a small fraction of the volume filled by the gas. On a molecular level, flow fields are made up of the collisions of many individual of gas molecules between themselves and with solid surfaces. However, in most aerodynamics applications,
1975-426: Is used because gas flows with a Mach number below that value demonstrate changes in density of less than 5%. Furthermore, that maximum 5% density change occurs at the stagnation point (the point on the object where flow speed is zero), while the density changes around the rest of the object will be significantly lower. Transonic, supersonic, and hypersonic flows are all compressible flows. The term Transonic refers to
2054-418: Is used in the design of mechanical components such as hard drive heads. Structural engineers resort to aerodynamics, and particularly aeroelasticity , when calculating wind loads in the design of large buildings, bridges , and wind turbines . The aerodynamics of internal passages is important in heating/ventilation , gas piping , and in automotive engines where detailed flow patterns strongly affect
2133-468: Is used to classify flows according to speed regime. Subsonic flows are flow fields in which the air speed field is always below the local speed of sound. Transonic flows include both regions of subsonic flow and regions in which the local flow speed is greater than the local speed of sound. Supersonic flows are defined to be flows in which the flow speed is greater than the speed of sound everywhere. A fourth classification, hypersonic flow, refers to flows where
2212-490: The Ancient Greek legend of Icarus and Daedalus . Fundamental concepts of continuum , drag , and pressure gradients appear in the work of Aristotle and Archimedes . In 1726, Sir Isaac Newton became the first person to develop a theory of air resistance, making him one of the first aerodynamicists. Dutch - Swiss mathematician Daniel Bernoulli followed in 1738 with Hydrodynamica in which he described
2291-621: The Grande Semaine d'Aviation de Tours , in the possession of the RAF College Cranwell , is also known as the Schneider Cup. Aircraft taking part had to be seaworthy, having to float for six hours and travel about 550 yards (503m) on water. Twice during the flight they had to land on or "come in contact" with the water (which allowed contestants to carry out a fast bouncing manoeuvre). If the pontoons took on water,
2370-750: The Schneider Trophy , Schneider Prize or (incorrectly) the Schneider Cup is a trophy that was awarded first annually, and later biennially, to the winner of a race for seaplanes and flying boats . In 1931 Britain met the conditions to retain the Trophy permanently; it was held at the Science Museum in South Kensington, London. Announced in 1912 by Jacques Schneider , a French financier, balloonist and aircraft enthusiast,
2449-416: The flow speed is below, near or above the speed of sound . A problem is called subsonic if all the speeds in the problem are less than the speed of sound, transonic if speeds both below and above the speed of sound are present (normally when the characteristic speed is approximately the speed of sound), supersonic when the characteristic flow speed is greater than the speed of sound, and hypersonic when
Gloster VI - Misplaced Pages Continue
2528-460: The 1926 race, as the military was unwilling to fund entrants. In 1927 at Venice the British responded by enlisting government backing and RAF pilots (the High Speed Flight ) for the Supermarine , Gloster , and Shorts entries. Supermarine's Mitchell-designed S.5s took first and second places; no other entrants finished. The race was witnessed by an estimated 250,000 spectators. 1927 was
2607-434: The 1929 Schneider Trophy, leaving the way clear for the Supermarine S.6 to win. An alternative theory for the withdrawal is rumoured to have been an accident to the lorry delivering the engines from Napier and insufficient time to repair the damage until the day after. On 10 September 1929, the day after the Supermarine S.6 had won the Trophy, N249 returned to flight. Flight Lieutenant George Stainforth flew it over
2686-586: The 1929 contest but was disqualified, is preserved at Solent Sky maritime museum in Southampton . Schneider was a hydroplane racer who came from a wealthy family; his interest in aircraft began after he met Wilbur Wright in 1908, but a boating accident in 1910 crippled him and prematurely ended his racing and flying career. Schneider served as a race referee at the Monaco Hydroplane Meet in 1912, where he noted that seaplane development
2765-574: The 1931 uncontested win, the development of the other 1931 entrants continued. The proposed Italian entrant (the Macchi M.C.72), which had pulled out of the contest due to engine problems, later went on to set two new world speed records with the help of British fuel expert Rod Banks, who had worked on the Rolls Royce R engine of the S6B. In April 1933 it set a record over Lake Garda in northern Italy with
2844-678: The Americans won again, with US pilot Jimmy Doolittle winning in a Curtiss R3C ahead of the British Gloster III and the Italian Macchi M.33 . R. J. Mitchell 's Supermarine S.4 and the other Gloster III were damaged before the race and did not compete. Two of the American planes did not finish. Benito Mussolini instructed the Italian aircraft industry to "win the Schneider Trophy at all costs" and so demonstrate
2923-428: The French and Italian teams dropped out, leaving no other competitors, the British team flew the course alone on 13 September and won the coveted Schneider Trophy outright, having beaten the time record from the 1929 competition. Reportedly half a million spectators lined the beachfronts. The Italian, French, and German entrants failed to ready their aircraft in time for the competition. The remaining British team set both
3002-484: The Italian team won. They were later disqualified and the race was voided, as the referees ruled they had incorrectly flown around a marker buoy. In 1920 and 1921 at Venice the Italians won again; in 1920 no other nation entered and in 1921 the French entry did not start. Had it not been for the 1919 disqualification, Italy would have been awarded the trophy permanently. After 1921, an additional requirement
3081-528: The aero club in the hosting country. Each club could enter up to three competitors with an equal number of alternatives. The Schneider Trophy is a sculpture of silver and bronze set on a marble base. It depicts a zephyr skimming the waves, and a nude winged figure is seen kissing a zephyr recumbent on a breaking wave. The heads of two other zephyrs and of Neptune , the god of the Sea, can be seen surrounded by octopus and crabs. The symbolism represents speed conquering
3160-412: The air is approximated as being significant only in this thin layer. This assumption makes the description of such aerodynamics much more tractable mathematically. In aerodynamics, turbulence is characterized by chaotic property changes in the flow. These include low momentum diffusion, high momentum convection, and rapid variation of pressure and flow velocity in space and time. Flow that is not turbulent
3239-568: The airflow is not supersonic. Supersonic aerodynamic problems are those involving flow speeds greater than the speed of sound. Calculating the lift on the Concorde during cruise can be an example of a supersonic aerodynamic problem. Supersonic flow behaves very differently from subsonic flow. Fluids react to differences in pressure; pressure changes are how a fluid is "told" to respond to its environment. Therefore, since sound is, in fact, an infinitesimal pressure difference propagating through
Gloster VI - Misplaced Pages Continue
3318-580: The amount of change of density in the flow. When the effects of compressibility on the solution are small, the assumption that density is constant may be made. The problem is then an incompressible low-speed aerodynamics problem. When the density is allowed to vary, the flow is called compressible. In air, compressibility effects are usually ignored when the Mach number in the flow does not exceed 0.3 (about 335 feet (102 m) per second or 228 miles (366 km) per hour at 60 °F (16 °C)). Above Mach 0.3,
3397-690: The choice between statistical mechanics and the continuous formulation of aerodynamics. The assumption of a fluid continuum allows problems in aerodynamics to be solved using fluid dynamics conservation laws . Three conservation principles are used: Together, these equations are known as the Navier–Stokes equations , although some authors define the term to only include the momentum equation(s). The Navier–Stokes equations have no known analytical solution and are solved in modern aerodynamics using computational techniques . Because computational methods using high speed computers were not historically available and
3476-633: The competition offered a prize of approximately £1,000. The race was held twelve times between 1913 and 1931, the year when it was finally won permanently by the British. It was intended to encourage technical advances in civil aviation but became a contest for pure speed with laps over a (usually) triangular course, initially 280 km (170 mi) and later extended to 350 km (220 mi). The contests were staged as time trials, with aircraft setting off individually at set intervals, usually 15 minutes apart. The contests were very popular, and some of them attracted crowds of over 200,000 spectators. The race
3555-462: The continuum assumption is reasonable. The continuum assumption is less valid for extremely low-density flows, such as those encountered by vehicles at very high altitudes (e.g. 300,000 ft/90 km) or satellites in Low Earth orbit . In those cases, statistical mechanics is a more accurate method of solving the problem than is continuum aerodynamics. The Knudsen number can be used to guide
3634-448: The course (both Macchi M.67s ), with the older Macchi M.52R taking second and Supermarine S.5 taking third. Although France had ordered racing seaplanes from Bernard and Nieuport-Delage in 1928, they were unable to complete them in time for the 1929 race. In 1931 the British government withdrew support, but a private donation of £100,000 from the wealthy and ultra-patriotic Lucy, Lady Houston , allowed Supermarine to compete. When
3713-542: The design being discarded and this meant a monoplane configuration was chosen for the new design. The Gloster VI was a low-winged braced monoplane. An obvious feature in photographs is the way that the wing roots tapered so as to reduce in thickness, designed to increase lateral control at low speeds. It retained the Napier Lion engine that had powered the previous Gloster racers, but with power boosted to 1,320 hp (985 kW) by supercharging . Engine cooling
3792-463: The desire to improve the aerodynamic efficiency of current aircraft and propulsion systems, continues to motivate new research in aerodynamics, while work continues to be done on important problems in basic aerodynamic theory related to flow turbulence and the existence and uniqueness of analytical solutions to the Navier–Stokes equations. Understanding the motion of air around an object (often called
3871-437: The discrete molecular nature of gases is ignored, and the flow field is assumed to behave as a continuum . This assumption allows fluid properties such as density and flow velocity to be defined everywhere within the flow. The validity of the continuum assumption is dependent on the density of the gas and the application in question. For the continuum assumption to be valid, the mean free path length must be much smaller than
3950-489: The effectiveness of his Fascist government. In 1926, the Italians returned with a Macchi M.39 and won against the Americans with a 396.69 km/h (246.49 mph) run at Hampton Roads . The United States, short of funds, did not develop new aircraft for the 1926 title defence; the M.39, designed by Mario Castoldi , used a Fiat AS2 engine and was streamlined in the manner of the 1925 Supermarine and Curtiss entrants. The American teams withdrew from further competition after
4029-693: The elements of sea and air. The cost of the trophy was 25,000 francs. After the British finally won permanent possession of the trophy in 1931, the sculpture was displayed for many years at the end of the corridor outside the ballroom of the Lansdowne Club. It has since been entrusted to the Royal Aero Club and can be viewed along with the winning Supermarine S.6B floatplane at the London Science Museum Flight exhibition hall. Supermarine S.6, N248 , which competed in
SECTION 50
#17327810962334108-603: The first flights, Frederick W. Lanchester , Martin Kutta , and Nikolai Zhukovsky independently created theories that connected circulation of a fluid flow to lift. Kutta and Zhukovsky went on to develop a two-dimensional wing theory. Expanding upon the work of Lanchester, Ludwig Prandtl is credited with developing the mathematics behind thin-airfoil and lifting-line theories as well as work with boundary layers . As aircraft speed increased designers began to encounter challenges associated with air compressibility at speeds near
4187-453: The first half of the 1800s, resulting in the Navier–Stokes equations . The Navier–Stokes equations are the most general governing equations of fluid flow but are difficult to solve for the flow around all but the simplest of shapes. In 1799, Sir George Cayley became the first person to identify the four aerodynamic forces of flight ( weight , lift , drag , and thrust ), as well as the relationships between them, and in doing so outlined
4266-520: The flight had to continue with the added weight. Each competition was to be held in and managed by the country currently holding the trophy. If a country won three consecutive races, as the British finally did, they would retain the trophy permanently and the winning pilot would receive 75,000 French francs for each of the first three wins. The races were supervised by the Fédération Aéronautique Internationale and
4345-477: The flow pattern ahead of the object and giving the impression that the fluid "knows" the object is there by seemingly adjusting its movement and is flowing around it. In a supersonic flow, however, the pressure disturbance cannot propagate upstream. Thus, when the fluid finally reaches the object it strikes it and the fluid is forced to change its properties – temperature , density , pressure , and Mach number —in an extremely violent and irreversible fashion called
4424-458: The flow speed is much greater than the speed of sound. Aerodynamicists disagree on the precise definition of hypersonic flow. Compressible flow accounts for varying density within the flow. Subsonic flows are often idealized as incompressible, i.e. the density is assumed to be constant. Transonic and supersonic flows are compressible, and calculations that neglect the changes of density in these flow fields will yield inaccurate results. Viscosity
4503-570: The flow speed is much greater than the speed of sound. Aerodynamicists disagree over the precise definition of hypersonic flow; a rough definition considers flows with Mach numbers above 5 to be hypersonic. The influence of viscosity on the flow dictates a third classification. Some problems may encounter only very small viscous effects, in which case viscosity can be considered to be negligible. The approximations to these problems are called inviscid flows . Flows for which viscosity cannot be neglected are called viscous flows. An incompressible flow
4582-465: The high computational cost of solving these complex equations now that they are available, simplifications of the Navier–Stokes equations have been and continue to be employed. The Euler equations are a set of similar conservation equations which neglect viscosity and may be used in cases where the effect of viscosity is expected to be small. Further simplifications lead to Laplace's equation and potential flow theory. Additionally, Bernoulli's equation
4661-534: The last annual competition, the event was then mutually agreed to be held biennially to allow more development time. In 1929, at Calshot , Supermarine won again in the Supermarine S.6 with the new Rolls-Royce R engine with an average speed of 528.89 km/h (328.64 mph). Both Britain and Italy entered two new aircraft and a backup plane from the previous race. Three of the four new aircraft were disqualified (Supermarine S.6 N.248 ) or failed to finish
4740-433: The length scale of the application in question. For example, many aerodynamics applications deal with aircraft flying in atmospheric conditions, where the mean free path length is on the order of micrometers and where the body is orders of magnitude larger. In these cases, the length scale of the aircraft ranges from a few meters to a few tens of meters, which is much larger than the mean free path length. For such applications,
4819-403: The path toward achieving heavier-than-air flight for the next century. In 1871, Francis Herbert Wenham constructed the first wind tunnel , allowing precise measurements of aerodynamic forces. Drag theories were developed by Jean le Rond d'Alembert , Gustav Kirchhoff , and Lord Rayleigh . In 1889, Charles Renard , a French aeronautical engineer, became the first person to reasonably predict
SECTION 60
#17327810962334898-579: The performance of the engine. Urban aerodynamics are studied by town planners and designers seeking to improve amenity in outdoor spaces, or in creating urban microclimates to reduce the effects of urban pollution. The field of environmental aerodynamics describes ways in which atmospheric circulation and flight mechanics affect ecosystems. Aerodynamic equations are used in numerical weather prediction . Sports in which aerodynamics are of crucial importance include soccer , table tennis , cricket , baseball , and golf , in which most players can control
4977-485: The point where entire aircraft can be designed using computer software, with wind-tunnel tests followed by flight tests to confirm the computer predictions. Understanding of supersonic and hypersonic aerodynamics has matured since the 1960s, and the goals of aerodynamicists have shifted from the behaviour of fluid flow to the engineering of a vehicle such that it interacts predictably with the fluid flow. Designing aircraft for supersonic and hypersonic conditions, as well as
5056-459: The power needed for sustained flight. Otto Lilienthal , the first person to become highly successful with glider flights, was also the first to propose thin, curved airfoils that would produce high lift and low drag. Building on these developments as well as research carried out in their own wind tunnel, the Wright brothers flew the first powered airplane on December 17, 1903. During the time of
5135-421: The problem flow should be described using compressible aerodynamics. According to the theory of aerodynamics, a flow is considered to be compressible if the density changes along a streamline . This means that – unlike incompressible flow – changes in density are considered. In general, this is the case where the Mach number in part or all of the flow exceeds 0.3. The Mach 0.3 value is rather arbitrary, but it
5214-598: The race was revived, no longer for seaplanes and under different rules, by the Royal Aero Club of Great Britain to commemorate the 50th anniversary of Britain's ultimate retention of the Schneider Trophy. The original trophy remained in the Science Museum, a full-size replica was cast, and the race opened on a handicapped basis to any propeller–driven landplane capable of maintaining 100 miles per hour (160 km/h; 87 kn) in straight and level flight, and weighing up to 12,500 lb (5,700 kg). Pilots had to have
5293-559: The race. The preparation of the United States team, backed by government support and using Curtiss racing biplanes derived from inter-military competitions, increased the speed and the investment of a winning entry significantly. In 1924 the competition was cancelled as no other nation turned out to face the Americans: the Italians and the French withdrew; and both British craft crashed in pre-race trials. In 1925 at Chesapeake Bay
5372-777: The races until 1991. Since that time, the race has been run by the Royal Aero Club Records Racing and Rally Association along with the King's Cup and the British air racing championship . The venue has varied but is still flown on most occasions around a Solent-based course, usually around September of each year. Aerodynamics Modern aerodynamics only dates back to the seventeenth century, but aerodynamic forces have been harnessed by humans for thousands of years in sailboats and windmills, and images and stories of flight appear throughout recorded history, such as
5451-450: The speed of sound. The Mach number is used to evaluate whether the incompressibility can be assumed, otherwise the effects of compressibility must be included. Subsonic (or low-speed) aerodynamics describes fluid motion in flows which are much lower than the speed of sound everywhere in the flow. There are several branches of subsonic flow but one special case arises when the flow is inviscid , incompressible and irrotational . This case
5530-459: The speed of sound. The differences in airflow under such conditions lead to problems in aircraft control, increased drag due to shock waves , and the threat of structural failure due to aeroelastic flutter . The ratio of the flow speed to the speed of sound was named the Mach number after Ernst Mach who was one of the first to investigate the properties of the supersonic flow. Macquorn Rankine and Pierre Henri Hugoniot independently developed
5609-446: The theory for flow properties before and after a shock wave , while Jakob Ackeret led the initial work of calculating the lift and drag of supersonic airfoils. Theodore von Kármán and Hugh Latimer Dryden introduced the term transonic to describe flow speeds between the critical Mach number and Mach 1 where drag increases rapidly. This rapid increase in drag led aerodynamicists and aviators to disagree on whether supersonic flight
5688-530: Was Gloster 's final evolution of a series of racing floatplanes, designed specifically for the Schneider Trophy . It progressed from the Gloster II , through the successful Gloster III (placed 2nd in 1925), and Gloster IV biplanes . While Henry Folland , Gloster's chief designer commenced work on a further revised biplane, the Gloster V, to enter the 1929 competition, centre of gravity problems led to
5767-490: Was achievable until the sound barrier was broken in 1947 using the Bell X-1 aircraft. By the time the sound barrier was broken, aerodynamicists' understanding of the subsonic and low supersonic flow had matured. The Cold War prompted the design of an ever-evolving line of high-performance aircraft. Computational fluid dynamics began as an effort to solve for flow properties around complex objects and has rapidly grown to
5846-528: Was added: the winning seaplane had to remain moored to a buoy for six hours without human intervention. In 1922 in Naples the British and French competed with the Italians. The British private entry, a Supermarine Sea Lion II , was the victor, flown by Henry Biard . The French aircraft did not start the race, which became a competition between the Sea Lion and three Italian aircraft, two Macchi M.17s and
5925-468: Was lagging land-based aircraft; seeking to spur amphibious aircraft development, capable of reliable operation, extended range, and reasonable payload capacity, he announced the annual Schneider Trophy competition at a race banquet on 5 December, to cover a distance of at least 150 nautical miles (280 km; 170 mi). The first competition was held on 16 April 1913, at Monaco , consisting of six laps, 300 kilometres (190 mi) distance in total. It
6004-429: Was now on offer, meant that the entry list for the race was large enough to warrant the introduction of heats from 1985 onwards. (There were 62 entrants to the 1984 race, believed at the time to be the largest-ever in all forms of air racing.) The event received further boosts in 1986, when it was started by Prince Andrew, Duke of York and his fiancée Sarah Ferguson; in 1987, when the event was featured as one episode in
6083-720: Was significant in advancing aeroplane design, particularly in the fields of aerodynamics and engine design, and showed its results in the best fighters of World War II. The streamlined shape and the low drag, liquid-cooled engine pioneered by Schneider Trophy designs are obvious in the British Supermarine Spitfire , the American North American P-51 Mustang , and the Italian Macchi C.202 Folgore . An earlier 1910 trophy for land planes presented by Jacques Schneider, in France,
6162-435: Was via thin surface radiators on each wing. Two aircraft, with serial numbers N249 & N250 were built, the first flying on 25 August 1929 and the second on 31 August. The aircraft showed promise and high speed but had problems with fuel supply when banking, which led to engine cut-outs. For such a risky business as low-altitude air-racing, this was an unacceptable risk and the aircraft were withdrawn from competition in
6241-469: Was won by Maurice Prévost , piloting a French Deperdussin Monocoque (Coupe Schneider) at an average speed of 73.56 km/h (45.71 mph). Although Prévost had averaged a faster flying speed, he lost 50 minutes when he landed prematurely after losing count of the laps completed. All four entrants were flying French-made aircraft; two withdrew before completing the race. The British won in 1914 with
#232767