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24-521: The SZD-30 is largely constructed out of wood. The high-mounted wing incorporates air brakes on both the upper and lower surfaces. The inner section of the wing is constant-chord and the outer section is tapered . The forward section of the otherwise all-wood fuselage is made of fiberglass . The single-wheel main landing gear is fixed, the formed one-piece canopy is side-mounted, the fuselage can be equipped with radios and an oxygen system. There are also two baggage compartments. In 2011, following

48-473: A fixed-wing aircraft (including both gliders and powered aeroplanes ) is its arrangement of lifting and related surfaces. Aircraft designs are often classified by their wing configuration. For example, the Supermarine Spitfire is a conventional low wing cantilever monoplane of straight elliptical planform with moderate aspect ratio and slight dihedral. Many variations have been tried. Sometimes

72-401: A flat surface when laid convex-side up. The wing , horizontal stabilizer , vertical stabilizer and propeller /rotor blades of an aircraft are all based on aerofoil sections, and the term chord or chord length is also used to describe their width. The chord of a wing, stabilizer and propeller is determined by measuring the distance between leading and trailing edges in the direction of

96-468: A flat upper wing and dihedral on the lower wing, while the Hanriot HD-1 had dihedral on the upper wing but none on the lower. In a cranked or polyhedral wing the dihedral angle varies along the span. (Note that the description "cranked" varies in usage. See also Cranked arrow planform.) Some designs have no clear join between wing and fuselage, or body. This may be because one or other of these

120-514: A number of cases of glue failure in the wooden joints, leading to structural failure, the type certificate holder issued a bulletin which reduced a number of the limiting speeds of the aircraft. Specifically, the maximum speed ( V NE ) was reduced to 195 km/h (121 mph, 105 knots) and aerobatic flight was prohibited. Data from Australian Gliding Museum General characteristics Performance Wing configuration#Number and position of main planes The wing configuration of

144-424: A variety of reasons. A small degree of sweep is sometimes used to adjust the centre of lift when the wing cannot be attached in the ideal position for some reason, such as a pilot's visibility from the cockpit. Other uses are described below. Some types of variable geometry vary the wing sweep during flight: The angle of a swept wing may also be varied, or cranked, along the span: On a few asymmetrical aircraft

168-475: A wing has to be rigid and strong and consequently may be heavy. By adding external bracing, the weight can be greatly reduced. Originally such bracing was always present, but it causes a large amount of drag at higher speeds and has not been used for faster designs since the early 1930s. The types are: Wings can also be characterised as: The wing planform is the silhouette of the wing when viewed from above or below. See also variable geometry types which vary

192-441: Is able to change the number of planes in flight. The Nikitin-Shevchenko IS "folding fighter" prototypes were able to morph between biplane and monoplane configurations after takeoff by folding the lower wing up into a cavity in the underside of the upper wing. The slip wing is a variation on the polymorphic idea, in which a low-wing monoplane is fitted with a second detachable "slip" wing above it to assist takeoff. The upper wing

216-527: Is missing, or because they merge into each other: Some designs may fall into multiple categories depending on interpretation, for example many UAVs or drones can be seen either as a tailless blended wing-body or as a flying wing with a deep centre chord. A variable geometry aircraft is able to change its physical configuration during flight. Some types of variable geometry craft transition between fixed wing and rotary wing configurations. For more about these hybrids, see powered lift . A polymorphic wing

240-460: Is the coordinate along the wing span and c is the chord at the coordinate y . Other terms are as for SMC. The MAC is a two-dimensional representation of the whole wing. The pressure distribution over the entire wing can be reduced to a single lift force on and a moment around the aerodynamic center of the MAC. Therefore, not only the length but also the position of MAC is often important. In particular,

264-400: Is then released and discarded once in the air. The idea was first flown on the experimental Hillson Bi-mono . Aircraft may have additional minor aerodynamic surfaces. Some of these are treated as part of the overall wing configuration: Additional minor features may be applied to an existing aerodynamic surface such as the main wing: High-lift devices maintain lift at low speeds and delay

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288-460: Is used for calculating pitching moments. Standard mean chord (SMC) is defined as wing area divided by wing span: where S is the wing area and b is the span of the wing. Thus, the SMC is the chord of a rectangular wing with the same area and span as those of the given wing. This is a purely geometric figure and is rarely used in aerodynamics . Mean aerodynamic chord (MAC) is defined as: where y

312-424: The leading edge and trailing edge of an aerofoil . The chord length is the distance between the trailing edge and the point where the chord intersects the leading edge. The point on the leading edge used to define the chord may be the surface point of minimum radius. For a turbine aerofoil the chord may be defined by the line between points where the front and rear of a 2-dimensional blade section would touch

336-461: The above integral. The ratio of the length (or span ) of a rectangular-planform wing to its chord is known as the aspect ratio , an important indicator of the lift-induced drag the wing will create. (For wings with planforms that are not rectangular, the aspect ratio is calculated as the square of the span divided by the wing planform area.) Wings with higher aspect ratios will have less induced drag than wings with lower aspect ratios. Induced drag

360-539: The airflow. (If a wing has a rectangular planform , rather than tapered or swept, then the chord is simply the width of the wing measured in the direction of airflow.) The term chord is also applied to the width of wing flaps , ailerons and rudder on an aircraft. The term is also applied to compressor and turbine aerofoils in gas turbine engines such as turbojet , turboprop , or turbofan engines for aircraft propulsion. Many wings are not rectangular, so they have different chords at different positions. Usually,

384-433: The chord length is greatest where the wing joins the aircraft's fuselage (called the root chord ) and decreases along the wing toward the wing's tip (the tip chord ). Most jet aircraft use a tapered swept wing design. To provide a characteristic figure that can be compared among various wing shapes, the mean aerodynamic chord (abbreviated MAC ) is used, although it is complex to calculate. The mean aerodynamic chord

408-456: The configurations described here have flown (if only very briefly) on full-size aircraft. A few theoretical designs are also notable. Note on terminology: Most fixed-wing aircraft have left hand and right hand wings in a symmetrical arrangement. Strictly, such a pair of wings is called a wing plane or just plane. However, in certain situations it is common to refer to a plane as a wing, as in "a biplane has two wings", or alternatively to refer to

432-435: The distinction between them is blurred, for example the wings of many modern combat aircraft may be described either as cropped compound deltas with (forwards or backwards) swept trailing edge, or as sharply tapered swept wings with large leading edge root extensions (or LERX). Some are therefore duplicated here under more than one heading. This is particularly so for variable geometry and combined (closed) wing types. Most of

456-589: The left and right hand sides are not mirror-images of each other: The classic aerofoil section wing is unstable in pitch, and requires some form of horizontal stabilizing surface. Also it cannot provide any significant pitch control, requiring a separate control surface (elevator) mounted elsewhere - usually on the horizontal stabilizer. Angling the wings up or down spanwise from root to tip can help to resolve various design issues, such as stability and control in flight. Some biplanes have different degrees of dihedral/anhedral on different wings. The Sopwith Camel had

480-481: The lower. Long thought to reduce the interference caused by the low pressure air over the lower wing mixing with the high pressure air under the upper wing; however the improvement is minimal and its primary benefit is to improve access to the fuselage. It is common on many successful biplanes and triplanes. Backwards stagger is also seen in a few examples such as the Beechcraft Staggerwing . To support itself

504-439: The position of center of gravity (CG) of an aircraft is usually measured relative to the MAC, as the percentage of the distance from the leading edge of MAC to CG with respect to MAC itself. Note that the figure to the right implies that the MAC occurs at a point where leading or trailing edge sweep changes. That is just a coincidence. In general, this is not the case. Any shape other than a simple trapezoid requires evaluation of

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528-423: The stall to allow slower takeoff and landing speeds: On a swept wing, air tends to flow sideways as well as backwards and reducing this can improve the efficiency of the wing: Vortex devices maintain airflow at low speeds and delay the stall, by creating a vortex which re-energises the boundary layer close to the wing. Chord (aircraft) In aeronautics , the chord is an imaginary straight line joining

552-416: The whole thing as a wing, as in "a biplane wing has two planes". Where the meaning is clear, this article follows common usage, only being more precise where needed to avoid real ambiguity or incorrectness. Fixed-wing aircraft can have different numbers of wings: A fixed-wing aircraft may have more than one wing plane, stacked one above another: A staggered design has the upper wing slightly forward of

576-475: The wing planform during flight. The aspect ratio is the span divided by the mean or average chord. It is a measure of how long and slender the wing appears when seen from above or below. Most variable geometry configurations vary the aspect ratio in some way, either deliberately or as a side effect. The wing chord may be varied along the span of the wing, for both structural and aerodynamic reasons. Wings may be swept back, or occasionally forwards, for

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