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40-425: The Kennedy K-W is an American high-wing , strut-braced , single-seat glider that was designed by Harold Kennedy of Dodge City, Kansas , with assistance from Floyd Watson. The aircraft is notable for being assembled from certified powered aircraft components and also for having had an in-flight break-up. The K-W glider was assembled from a collection of certified fixed-wing aircraft parts. The aft fuselage

80-573: A rigid fixture . These formers are then joined with lightweight longitudinal elements called stringers . These are in turn covered with a skin of sheet aluminum, attached by riveting or by bonding with special adhesives. The fixture is then disassembled and removed from the completed fuselage shell, which is then fitted out with wiring, controls, and interior equipment such as seats and luggage bins. Most modern large aircraft are built using this technique, but use several large sections constructed in this fashion which are then joined with fasteners to form

120-485: A design is intended to be "self jigging", not requiring a complete fixture for alignment. Early aircraft were constructed of wood frames covered in fabric. As monoplanes became popular, metal frames improved the strength, which eventually led to all-metal-structure aircraft, with metal covering for all its exterior surfaces - this was first pioneered in the second half of 1915 . Some modern aircraft are constructed with composite materials for major control surfaces, wings, or

160-410: A few specialist types. Jet and rocket engines have even more power and all modern high-speed aircraft, especially supersonic types, have been monoplanes. Fuselage This type of structure is still in use in many lightweight aircraft using welded steel tube trusses. A box truss fuselage structure can also be built out of wood—often covered with plywood. Simple box structures may be rounded by

200-627: 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

240-496: A nearly finished product) is prevalent in the series production of many modern sailplanes . The use of molded composites for fuselage structures is being extended to large passenger aircraft such as the Boeing 787 Dreamliner (using pressure-molding on female molds). This is the preferred method of constructing an all- aluminum fuselage. First, a series of formers in the shape of the fuselage cross sections are held in position on

280-407: 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

320-470: 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

360-447: A portion of the external load (i.e. from wings and empennage, and from discrete masses such as the engine) is taken by the surface covering. In addition, all the load from internal pressurization is carried (as skin tension ) by the external skin. The proportioning of loads between the components is a design choice dictated largely by the dimensions, strength, and elasticity of the components available for construction and whether or not

400-548: A scratch pane near the passenger. Acrylic is susceptible to crazing  : a network of fine cracks appears but can be polished to restore optical transparency , removal and polishing typically undergo every 2–3 years for uncoated windows. " Flying wing " aircraft, such as the Northrop YB-49 Flying Wing and the Northrop B-2 Spirit bomber have no separate fuselage; instead what would be

440-489: 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

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480-432: 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 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

520-445: Is composed of 4–6 panels, 35 kg (77 lb) each on an Airbus A320 . In its lifetime, an average aircraft goes through three or four windshields , and the market is shared evenly between OEM and higher margins aftermarket . Cabin windows, made from much lighter than glass stretched acrylic glass , consists of multiple panes: an outer one built to support four times the maximum cabin pressure, an inner one for redundancy and

560-410: 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

600-571: 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

640-693: 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

680-463: The Lockheed Vega ) was built using molded plywood , where the layers of plywood are formed over a "plug" or within a mold . A later form of this structure uses fiberglass cloth impregnated with polyester or epoxy resin as the skin, instead of plywood. A simple form of this used in some amateur-built aircraft uses rigid expanded foam plastic as the core, with a fiberglass covering, eliminating

720-451: 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

760-725: 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

800-457: 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 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

840-410: The addition of supported lightweight stringers, allowing the fabric covering to form a more aerodynamic shape, or one more pleasing to the eye. Geodesic structural elements were used by Barnes Wallis for British Vickers between the wars and into World War II to form the whole of the fuselage, including its aerodynamic shape. In this type of construction multiple flat strip stringers are wound about

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880-522: The aircraft had a steel tube fuselage and wooden wings, all covered in doped aircraft fabric covering . A second aircraft was constructed along the same lines by Bob Dart of Mayville, New York and called the Aero-5. This aircraft still existed in May 2011. The K-W prototype was completed and flown in 1957 and accumulated 390 hours, the majority of which had been flown by Kennedy's two teenaged sons. The K-W

920-481: 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

960-525: 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

1000-636: The complete fuselage. As the accuracy of the final product is determined largely by the costly fixture, this form is suitable for series production, where many identical aircraft are to be produced. Early examples of this type include the Douglas Aircraft DC-2 and DC-3 civil aircraft and the Boeing B-17 Flying Fortress . Most metal light aircraft are constructed using this process. Both monocoque and semi-monocoque are referred to as "stressed skin" structures as all or

1040-641: The entire fuselage such as the Boeing 787. On the 787, it makes possible higher pressurization levels and larger windows for passenger comfort as well as lower weight to reduce operating costs. The Boeing 787 weighs 1,500 lb (680 kg) less than if it were an all-aluminum assembly. Cockpit windshields on the Airbus A320 must withstand bird strikes up to 350 kn (650 km/h) and are made of chemically strengthened glass . They are usually composed of three layers or plies, of glass or plastic :

1080-522: The formers in opposite spiral directions, forming a basket-like appearance. This proved to be light, strong, and rigid and had the advantage of being made almost entirely of wood. A similar construction using aluminum alloy was used in the Vickers Warwick with less material than would be required for other structural types. The geodesic structure is also redundant and so can survive localized damage without catastrophic failure. A fabric covering over

1120-497: The fuselage is a thickened portion of the wing structure. Conversely, there have been a small number of aircraft designs which have no separate wing, but use the fuselage to generate lift. Examples include National Aeronautics and Space Administration 's experimental lifting body designs and the Vought XF5U-1 Flying Flapjack . A blended wing body can be considered a mixture of the above. It carries

1160-402: 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

1200-433: 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

1240-634: The inner two are 8 mm (0.3 in.) thick each and are structural, while the outer ply, about 3 mm thick, is a barrier against foreign object damage and abrasion , with often a hydrophobic coating. It must prevent fogging inside the cabin and de-ice from −50 °C (−58 °F). This was previously done with thin wires similar to a rear car window but is now accomplished with a transparent, nanometers-thick coating of indium tin oxide sitting between plies, electrically conductive and thus transmitting heat. Curved glass improves aerodynamics but sight criteria also needs larger panes. A cockpit windshield

Kennedy K-W - Misplaced Pages Continue

1280-415: 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

1320-534: The necessity of fabricating molds, but requiring more effort in finishing (see the Rutan VariEze ). An example of a larger molded plywood aircraft is the de Havilland Mosquito fighter/light bomber of World War II . No plywood-skin fuselage is truly monocoque , since stiffening elements are incorporated into the structure to carry concentrated loads that would otherwise buckle the thin skin. The use of molded fiberglass using negative ("female") molds (which give

1360-410: 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

1400-462: The pilot was killed. The US National Transportation Safety Board identified the likely cause factors as that the pilot in command mishandled the flight controls and exceeded the stress limits of the aircraft. The NTSB also cited the pilot's lack of familiarity with the aircraft type. No further aircraft of the type were constructed. Data from Soaring General characteristics Performance Related lists High-wing A monoplane

1440-511: The structure completed the aerodynamic shell (see the Vickers Wellington for an example of a large warplane which uses this process). The logical evolution of this is the creation of fuselages using molded plywood, in which several sheets are laid with the grain in differing directions to give the monocoque type below. In this method, the exterior surface of the fuselage is also the primary structure. A typical early form of this (see

1480-453: 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

1520-439: 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

1560-465: Was being flown by a 27-year-old private pilot with 56 hours total time and four hours on type, on 10 August 1975 from the Fowler Airport located near Fowler, Kansas . The glider was being launched by aerotow and when the glider attempted to release the tow rope the righthand wing struts separated from the fuselage at the attachment fitting due to an overload failure. The aircraft crashed and

1600-556: Was from an Aeronca Chief , with the welded steel tubing structure narrowed from a two seats in side-by-side seating configuration to a single seat width. The vertical fin from the Chief was retained. The tailplane was from a Taylorcraft , reduced in span to 8 ft (2.4 m) to allow road transportation on a trailer. The single monowheel landing gear, wings and V- struts were taken from an Aeronca K . The wings were modified to add spoilers . Because of its component parts heritage,

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