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38-572: The Schreder HP-13 is an American high-wing , single seat FAI Open Class glider that was designed by Richard Schreder . The HP-13 ( HP stands for high performance ) was a developmental milestone aircraft between the HP-11 and the later HP-14 . The HP-13 was designed by taking the fuselage of the HP-11 and wings similar to the HP-12, featuring the same Wortmann FX 61-163 airfoil but extended from

76-408: A biplane , a parasol wing has less bracing and lower drag. It remains a popular configuration for amphibians and small homebuilt and ultralight aircraft . Although the first successful aircraft were biplanes, the first attempts at heavier-than-air flying machines were monoplanes, and many pioneers continued to develop monoplane designs. For example, the first aeroplane to be put into production

114-481: A grid which allowed engine exhaust to be channeled away from the aircraft to avoid suckdown and HGI effects. Ventral strakes retroactively fitted to the P.1127 improved flow and increased pressure under the belly in low altitude hovering. Gun pods fitted in the same position on the production Harrier GR.1/GR.3 and the AV-8A Harrier did the same thing. Further lift improvement devices (LIDS) were developed for

152-544: A low-wing, shoulder-wing and high-wing configurations give increased propeller clearance on multi-engined aircraft. On a large aircraft, there is little practical difference between a shoulder wing and a high wing; but on a light aircraft, the configuration is significant because it offers superior visibility to the pilot. On light aircraft, shoulder-wings tend to be mounted further aft than a high wing, and so may need to be swept forward to maintain correct center of gravity . Examples of light aircraft with shoulder wings include

190-441: A pylon. Additional bracing may be provided by struts or wires extending from the fuselage sides. The first parasol monoplanes were adaptations of shoulder wing monoplanes, since raising a shoulder mounted wing above the fuselage greatly improved visibility downwards, which was useful for reconnaissance roles, as with the widely used Morane-Saulnier L . The parasol wing allows for an efficient design with good pilot visibility, and

228-467: Is a configuration whereby the wing is mounted near the top of the fuselage but not on the very top. It is so called because it sits on the "shoulder" of the fuselage, rather than on the pilot's shoulder. Shoulder-wings and high-wings share some characteristics, namely: they support a pendulous fuselage which requires no wing dihedral for stability; and, by comparison with a low-wing, a shoulder-wing's limited ground effect reduces float on landing. Compared to

266-407: Is the result of entrainment of air around aircraft by lift jets when hovering. It also occurs in free air (OGE) causing loss of lift by reducing pressures on the underside of the fuselage and wings. Enhanced entrainment occurs when close to the ground giving higher lift loss. Fountain lift occurs when an aircraft has two or more lift jets. The jets strike the ground and spread out. Where they meet under

304-644: The ARV Super2 , the Bölkow Junior , Saab Safari and the Barber Snark . A high wing has its upper surface on or above the top of the fuselage. It shares many advantages and disadvantages with the shoulder wing, but on a light aircraft, the high wing has poorer upwards visibility. On light aircraft such as the Cessna 152 , the wing is usually located above the cabin, so that the wing spar passes over

342-554: The Federal Aviation Administration , all in the Experimental - Amateur-built category. Data from Sailplane Directory and Soaring General characteristics Performance High-wing A monoplane is a fixed-wing aircraft configuration with a single mainplane, in contrast to a biplane or other types of multiplanes , which have multiple planes. A monoplane has inherently

380-499: The Gulfstream G650 business jet the test aircraft rotated to an angle beyond the predicted IGE stalling angle. The over-rotation caused one wing-tip to stall and an uncommanded roll, which overpowered the lateral controls, leading to loss of the aircraft. A few vehicles have been designed to explore the performance advantages of flying in ground effect, mainly over water. The operational disadvantages of flying very close to

418-440: The cantilever wing more practical — first pioneered together by the revolutionary German Junkers J 1 factory demonstrator in 1915–16 — they became common during the post–World War I period, the day of the braced wing passed, and by the 1930s, the cantilever monoplane was fast becoming the standard configuration for a fixed-wing aircraft. Advanced monoplane fighter-aircraft designs were mass-produced for military services around

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456-462: The cantilever wing, which carries all structural forces internally. However, to fly at practical speeds the wing must be made thin, which requires a heavy structure to make it strong and stiff enough. External bracing can be used to improve structural efficiency, reducing weight and cost. For a wing of a given size, the weight reduction allows it to fly slower and with a lower-powered and more economical engine. For this reason, all monoplane wings in

494-429: The static source . When a hovering rotor is near the ground the downward flow of air through the rotor is reduced to zero at the ground. This condition is transferred up to the disc through pressure changes in the wake which decreases the inflow to the rotor for a given disc loading, which is rotor thrust for each square foot of its area. This gives a thrust increase for a particular blade pitch angle, or, alternatively,

532-537: The " Fokker scourge ". The German military Idflieg aircraft designation system prior to 1918 prefixed monoplane type designations with an E , until the approval of the Fokker D.VIII fighter from its former "E.V" designation. However, the success of the Fokker was short-lived, and World War I was dominated by biplanes. Towards the end of the war, the parasol monoplane became popular and successful designs were produced into

570-419: The "floating" effect. Ground effect also alters thrust versus velocity, where reduced induced drag requires less thrust in order to maintain the same velocity. Low winged aircraft are more affected by ground effect than high wing aircraft. Due to the change in up-wash, down-wash, and wingtip vortices, there may be errors in the airspeed system while in ground effect due to changes in the local pressure at

608-428: The "ram" or "cushion" effect, and thereby improves the aircraft lift-to-drag ratio. The lower/nearer the wing is to the ground, the more pronounced the ground effect becomes. While in the ground effect, the wing requires a lower angle of attack to produce the same amount of lift. In wind tunnel tests, in which the angle of attack and airspeed remain constant, an increase in the lift coefficient ensues, which accounts for

646-405: The 1920s. Nonetheless, relatively few monoplane types were built between 1914 and the late 1920s, compared with the number of biplanes. The reasons for this were primarily practical. With the low engine powers and airspeeds available, the wings of a monoplane needed to be large in order to create enough lift while a biplane could have two smaller wings and so be made smaller and lighter. Towards

684-577: The AV-8B and Harrier II. To box in the belly region where the lift-enhancing fountains strike the aircraft, strakes were added to the underside of the gun pods and a hinged dam could be lowered to block the gap between the front ends of the strakes. This gave a 1200 lb lift gain. Lockheed Martin F-35 Lightning II weapons-bay inboard doors on the F-35B open to capture fountain flow created by

722-574: The HP-12's 49.2 ft (15 m) FAI Standard Class span to 54 ft 7 in (16.64 m) for the open class. Eight HP-13s were completed. The HP-13 was later developed into the HP-14 by designing a new fuselage for the wings. The HP-14 was later type certified in the United Kingdom , while the HP-13s were all amateur-built . In April 2011 there were still five HP-13s registered with

760-506: The air frame, fountain impingement on the underside of the fuselage and HGI into the engine causing inlet temperature rise (ITR). Suckdown works against the engine lift as a downward force on the airframe. Fountain flow works with the engine lift jets as an upwards force. The severity of the HGI problem becomes clear when the level of ITR is converted into engine thrust loss, three to four percent per 12.222 °c inlet temperature rise. Suckdown

798-413: The airframe and loss in hovering thrust if the engine sucks in its own exhaust gas, which is known as hot gas ingestion (HGI). When an aircraft flies at or below approximately half the length of the aircraft's wingspan above the ground or water there occurs an often-noticeable ground effect. The result is lower induced drag on the aircraft. This is caused primarily by the ground or water obstructing

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836-418: The creation of wingtip vortices and interrupting downwash behind the wing. A wing generates lift by deflecting the oncoming airmass (relative wind) downward. The deflected or "turned" flow of air creates a resultant force on the wing in the opposite direction (Newton's 3rd law). The resultant force is identified as lift. Flying close to a surface increases air pressure on the lower wing surface, nicknamed

874-478: The end of the First World War, the inherent high drag of the biplane was beginning to restrict performance. Engines were not yet powerful enough to make the heavy cantilever-wing monoplane viable, and the braced parasol wing became popular on fighter aircraft, although few arrived in time to see combat. It remained popular throughout the 1920s. On flying boats with a shallow hull, a parasol wing allows

912-525: The engine and fan lift jets and counter suckdown IGE. The stalling angle of attack is less in ground effect, by approximately 2–4 degrees, than in free air. When the flow separates there is a large increase in drag. If the aircraft overrotates on take-off at too low a speed the increased drag can prevent the aircraft from leaving the ground. Two de Havilland Comets overran the end of the runway after overrotating. Loss of control may occur if one wing tip stalls in ground effect. During certification testing of

950-521: The engine is hotter and less dense than cold air. Early VTOL experimental aircraft operated from open grids to channel away the engine exhaust and prevent thrust loss from HGI. The Bell X-14 , built to research early VTOL technology, was unable to hover until suckdown effects were reduced by raising the aircraft with longer landing gear legs. It also had to operate from an elevated platform of perforated steel to reduce HGI. The Dassault Mirage IIIV VTOL research aircraft only ever operated vertically from

988-487: The engines to be mounted above the spray from the water when taking off and landing. This arrangement was popular on flying boats during the 1930s; a late example being the Consolidated PBY Catalina . It died out when taller hulls became the norm during World War II, allowing a high wing to be attached directly to the hull. As ever-increasing engine powers made the weight of all-metal construction and

1026-413: The fuselage they mix and can only move upwards striking the underside of the fuselage. How well their upward momentum is diverted sideways or downward determines the lift. Fountain flow follows a curved fuselage underbody and retains some momentum in an upward direction so less than full fountain lift is captured unless lift improvement devices are fitted. HGI reduces engine thrust because the air entering

1064-427: The ground. Ground effect is at its maximum over a firm, smooth surface. There are two effects inherent to VTOL aircraft operating at zero and low speeds in ground effect, suckdown and fountain lift. A third, hot gas ingestion, may also apply to fixed-wing aircraft on the ground in windy conditions or during thrust reverser operation. How well, in terms of weight lifted, a VTOL aircraft hovers IGE depends on suckdown on

1102-406: The highest efficiency and lowest drag of any wing configuration and is the simplest to build. However, during the early years of flight, these advantages were offset by its greater weight and lower manoeuvrability, making it relatively rare until the 1930s. Since then, the monoplane has been the most common form for a fixed-wing aircraft. The inherent efficiency of the monoplane is best achieved in

1140-427: The low-wing position is its significant ground effect , giving the plane a tendency to float farther before landing. Conversely, this ground effect permits shorter takeoffs. A mid wing is mounted midway up the fuselage. The carry-through spar structure can reduce the useful fuselage volume near its centre of gravity, where space is often in most demand. A shoulder wing (a category between high-wing and mid-wing)

1178-554: The main distinction between types of monoplane is where the wing is mounted vertically on the fuselage . A low wing is one which is located on or near the bottom of the fuselage. Placing the wing low allows good visibility upwards and frees the central fuselage from the wing spar carry-through. By reducing pendulum stability, it makes the aircraft more manoeuvrable, as on the Spitfire ; but aircraft that value stability over manoeuvrability may then need some dihedral . A feature of

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1216-447: The occupants' heads, leaving the wing in the ideal fore-aft position. An advantage of the high-wing configuration is that the fuselage is closer to the ground which eases cargo loading, especially for aircraft with a rear-fuselage cargo door. Military cargo aircraft are predominantly high-wing designs with a rear cargo door. A parasol wing is not directly attached to the fuselage but held above it, supported by either cabane struts or

1254-416: The pioneer era were braced and most were up until the early 1930s. However, the exposed struts or wires create additional drag, lowering aerodynamic efficiency and reducing the maximum speed. High-speed and long-range designs tend to be pure cantilevers, while low-speed short-range types are often given bracing. Besides the general variations in wing configuration such as tail position and use of bracing,

1292-399: The power required for a thrust is reduced. For an overloaded helicopter that can only hover IGE it may be possible to climb away from the ground by translating to forward flight first while in ground effect. The ground-effect benefit disappears rapidly with speed but the induced power decreases rapidly as well to allow a safe climb. Some early underpowered helicopters could only hover close to

1330-591: The rotor during hovering close to the ground. At high weights this sometimes allows the rotorcraft to lift off while stationary in ground effect but does not allow it to transition to flight out of ground effect. Helicopter pilots are provided with performance charts which show the limitations for hovering their helicopter in ground effect (IGE) and out of ground effect (OGE). The charts show the added lift benefit produced by ground effect. For fan- and jet-powered vertical take-off and landing (VTOL) aircraft, ground effect when hovering can cause suckdown and fountain lift on

1368-778: The world in both the Soviet Union and the United States in the early–mid 1930s, with the Polikarpov I-16 and the Boeing P-26 Peashooter respectively. Most military aircraft of WWII were monoplanes, as have been virtually all aircraft since, except for a few specialist types. Jet and rocket engines have even more power and all modern high-speed aircraft, especially supersonic types, have been monoplanes. Ground effect (aerodynamics) For rotorcraft , ground effect results in less drag on

1406-466: Was adopted for some fighters such as the Fokker D.VIII and Morane-Saulnier AI in the later part of the First World War. A parasol wing also provides a high mounting point for engines and during the interwar period was popular on flying boats, which need to lift the propellers clear of spray. Examples include the Martin M-130 , Dornier Do 18 and the Consolidated PBY Catalina . Compared to

1444-553: Was the 1907 Santos-Dumont Demoiselle , while the Blériot XI flew across the English Channel in 1909. Throughout 1909–1910, Hubert Latham set multiple altitude records in his Antoinette IV monoplane, eventually reaching 1,384 m (4,541 ft). The equivalent German language term is Eindecker , as in the mid-wing Fokker Eindecker fighter of 1915 which for a time dominated the skies in what became known as

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