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40-543: The Youngman-Baynes High Lift was a British experimental aircraft of the 1940s. It was a single-engine, low-wing monoplane with a fixed tailwheel undercarriage. The High Lift was a "one-off" experimental, flying test-bed for the system of slotted flaps invented by R.T. Youngman . It was designed by L. E. Baynes AFRAeS, using components from the Percival Proctor , and built by Heston Aircraft Company Ltd. Test pilot Flight Lieutenant Ralph S Munday piloted

80-484: A few specialist types. Jet and rocket engines have even more power and all modern high-speed aircraft, especially supersonic types, have been monoplanes. Forward-swept wing The forward-swept configuration has a number of characteristics which increase as the angle of sweep increases. The aft location of the main wing spar would lead to a more efficient interior arrangement with more usable space. Air flowing over any swept wing tends to move spanwise towards

120-627: 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 the ARV Super2 , the Bölkow Junior , Saab Safari and the Barber Snark . A high wing has its upper surface on or above

160-407: 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 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

200-470: 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 was the 1907 Santos-Dumont Demoiselle , while the Blériot XI flew across

240-542: A significant aft movement of the main spar attachment point and carry-through structure. In 1954, Wocke returned to the German Democratic Republic, moving to West Germany shortly afterwards and joining Hamburger Flugzeugbau (HFB) as their chief designer. In Hamburg, Wocke completed work on the HFB 320 Hansa Jet business jet which flew in 1964. The forward sweep enabled the main spar to be moved aft behind

280-409: A single mainplane, in contrast to a biplane or other types of multiplanes , which have multiple planes. A monoplane has inherently 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,

320-489: 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 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

360-403: Is sufficient, it can counteract this tendency by increasing the angle of attack at the wing tips to such an extent that the tips stall first and one of the main characteristics of the design is lost, on a conventional wing the tips always stall first. Such a tip stall can be unpredictable, especially where one tip stalls before the other. Composite materials allow aeroelastic tailoring, so that as

400-410: 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 a pylon. Additional bracing may be provided by struts or wires extending from

440-556: Is the divergence speed of the aircraft. Such an increase in tip lift under load causes the wing to tighten into turns and may result in a spiral dive from which recovery is not possible. In the worst case, the wing structure can be stressed to the point of failure. At large angles of sweep and high speeds, in order to build a structure stiff enough to resist deforming yet light enough to be practicable, advanced materials such as carbon fiber composites are required. Composites also allow aeroelastic tailoring by aligning fibers to influence

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480-486: Is the increased chance of divergence, an aeroelastic consequence of the lift force on forward swept wings twisting the tip upwards under increased lift. On a forward-swept design, this causes a positive feedback loop that increases the angle of incidence at the tip, increasing lift and inducing further deflection, resulting in yet more lift and additional changes in wing shape. The effect of divergence increases with speed. The maximum safe speed below which this does not happen

520-571: 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 the " Fokker scourge ". The German military Idflieg aircraft designation system prior to 1918 prefixed monoplane type designations with an E , until

560-693: 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 a biplane , a parasol wing has less bracing and lower drag. It remains

600-764: The Schleicher ASK 13 and the Let Kunovice LET L-13 Blaník . Other examples include: The large angles of sweep necessary for high-speed flight remained impractical for many years. In the late 1970s, DARPA began investigating the use of newer composite materials to avoid the problem of reduced divergence speed through aeroelastic tailoring. Fly-by-wire technology allowed for the design to be dynamically unstable and improved maneuverability. Grumman built two X-29 technology demonstrators, first flying in 1984, with forward swept wings and canards . Maneuverable at high angles of attack ,

640-451: 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 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

680-725: 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 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

720-760: The Soviet Union created the Tsybin LL-3. The prototype would subsequently have a great impact on the Sukhoi SYB-A, which was completed in 1982. When the German research reached the United States after the war, a number of proposals were put forward. These included the Convair XB-53 supersonic bomber and forward-swept variants of the North American P-51 Mustang , Bell X-1 rocket plane and Douglas D-558-I . The Bell proposal reached

760-620: The X-29 remained controllable at a 67° angle of attack. Advances in thrust vectoring technology and a shift in air combat tactics toward medium range missile engagements decreased the relevance of a highly agile fighter aircraft. In 1997, Sukhoi introduced the Su-47 fighter prototype at the Paris Air Show . It did not enter production, although it underwent a series of flight tests and performed at several air shows . The KB SAT SR-10

800-496: The aftmost end of the wing. On a rearward-swept wing this is outwards towards the tip, while on a forward-swept wing it is inwards towards the root. As a result, the dangerous tip stall condition of a rearward-swept design becomes a safer and more controllable root stall on a forward-swept design. This allows full aileron control despite loss of lift, and also means that drag-inducing leading edge slots or other devices are not required. At transonic speeds, shockwaves build up first at

840-481: The aircraft more manoeuvrable, as on the Spitfire ; but aircraft that value stability over manoeuvrability may then need some dihedral . A feature of 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

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880-525: 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 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

920-699: The average chord of their wings being forward-sweeping. However, these designs almost always utilized a rearward-swept leading edge, which would technically render them as high aspect ratio trapezoidal wings . The American Cornelius Mallard flew on 18 August 1943. The Mallard was powered by a single engine, but it was followed by the Cornelius XFG-1 prototypes, which were flying fuel tanks, unpowered and designed for towing by larger aircraft. These Cornelius designs were unusual for being not only forward swept but also tailless. Meanwhile in Germany, Hans Wocke

960-434: The cabin so that the spar did not need to project into the cabin. Moderate forward sweep has been used for similar reasons in many designs, mainly sailplanes and light aircraft . Many high-wing training gliders with two seats in tandem have slightly forward-swept wings in order to enable the wing root to be located further aft to prevent the wing from obscuring the rear occupant's lateral visibility. Typical examples are

1000-475: The first flight at Heston Aerodrome on 5 February 1948, carrying the military serial VT789. The High Lift was registered as G-AMBL on 10 May 1950. Its career ended in 1954 when it was presented to the College of Aeronautics at Cranfield . Data from General characteristics Performance Related development Monoplane A monoplane is a fixed-wing aircraft configuration with

1040-424: The forward-swept design is that when a swept wing yaws sideways (moves about its vertical axis), one wing retreats while the other advances. On a forward-swept design, this reduces the sweep of the rearward wing, increasing its drag and pushing it further back, increasing the amount of yaw and leading to directional instability. This can lead to a Dutch roll in reverse. One of the drawbacks of forward swept wings

1080-402: 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 was adopted for some fighters such as

1120-433: The general variations in wing configuration such as tail position and use of bracing, 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

1160-415: 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 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

1200-474: The low-speed advantages but also soon revealed the expected problems, preventing high-speed trials. Wocke and the incomplete Ju 287 V3 prototype were captured and, in 1946, taken to Moscow where the aircraft was completed and flown the next year as the OKB-1 EF 131 . The later OKB-1 EF 140 was essentially the same airframe re-engined with a pair of Mikulin-design Soviet jet engines of greater thrust. In 1948,

1240-434: The monoplane has been the most common form for a fixed-wing aircraft. The inherent efficiency of the monoplane is best achieved in 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

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1280-417: The nature of deformation to a more favorable shape, impacting stall and other characteristics. Any swept wing tends to be unstable in the stall , since the wing tips stalls first causing a pitch-up force worsening the stall and making recovery difficult. This effect is less significant with forward sweep because the rearward end carries greater lift and provides stability. However, if the aeroelastic bending

1320-410: 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 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

1360-608: The prewar period, were developed during World War II, independently in Germany, the Soviet Union, Japan, and the United States. An early example to fly, in 1940, was the Soviet Belyayev DB-LK , a twin-boom design with forward-swept outer wing sections and backwards-swept tips. It reportedly flew well. Belyayev's proposed Babochka research aircraft was cancelled following the German invasion. Throughout World War II, numerous fighter, bomber, and other military aircraft can be described as having forward-swept wings, due to

1400-440: The root rather than the tip, again helping ensure effective aileron control. With the air flowing inwards, wingtip vortices and the accompanying drag are reduced. Instead, the fuselage acts as a very large wing fence and, since wings are generally larger at the root, this raises the maximum lift coefficient allowing a smaller wing. As a result, maneuverability is improved, especially at high angles of attack . One problem with

1440-453: 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 the occupants' heads, leaving the wing in the ideal fore-aft position. An advantage of the high-wing configuration

1480-439: 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) 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

1520-657: The wind tunnel testing stage, where the problems of aeroelasticity were confirmed. The structural problems confirmed by the Ju 287 series and the Bell X-1 studies proved so severe that the materials available at the time could not make a wing strong and stiff enough without also making it too heavy to be practical. As a result, forward sweep for high-speed designs was abandoned, until many years later when new structural materials would become available. Small amounts of sweep do not cause serious problems and even moderate forward sweep allows

1560-576: The wing approaches the stall it twists as it bends, so as to reduce the angle of attack at the tips. This ensures that the stall occurs at the wing root, making it more predictable and allowing the ailerons to retain full control. Belyaev, the author of the below mentioned DB-LK project, tested forward-swept wing gliders BP-2 and BP-3 in 1934 and 1935. Other prewar design studies included the Polish PWS Z-17, Z-18 and Z-47 "Sęp" series. Forward-swept wings designs, some whose design had begun during

1600-490: Was studying the problems of swept wings at the near-sonic speeds of which the new jet engines were capable. He recognised many of the advantages that forward sweep offered over the backwards-swept designs then being developed, and also understood the implications of aeroelastic bending and yaw instability. His first such design to fly was the Junkers Ju 287 , on 16 August 1944. Flight tests on this and later variants confirmed

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