Abstract: A method of forming a multilayer ceramic coating system on a substrate that requires thermal protection from a hostile thermal environment. The method generally entails forming at least one tape that contains ceramic particles dispersed in an organic constituent, such as a binder and/or plasticizer. If a single tape is used, the tape is formed of multiple layers of different compositions and applied as a unit to the substrate, thereby forming at least an innermost layer and an outermost layer on the substrate. If multiple tapes are used, a first tape is applied to the substrate to form the innermost layer, and a second tape is applied to form the outermost layer. The tape/tapes are then sintered to form innermost and outermost ceramic layers, respectively, on the substrate.

Abstract: A lift body has a variable camber to achieve a flow-favorable profile. The lift body has a structure which is elastically deformable at least in one area. An integrated adjusting device includes at least one dimensionally stable adjusting body which can be rotated about an axis and which is in an operative connection with the deformable structure. Each adjusting body has a curved conical shape whose local cross-section corresponds to the local profile thickness. Each adjusting body is in a direct and/or, via a sliding layer, an indirect contact with the deformable structure.

Abstract: A wing in combination with a fuselage having a body which is elongated in the direction of flight, the wing having physical parameters [comprising a wing having a relatively unswept and sharp leading edge, smooth convex chordwise contour over a majority of its surface from the leading edge, and a thickness to chord ratio of about 2% or less as a spanwise average, beyond a spanwise distance from the fuselage centerline of not more than about C/2.beta. on each side of the body, where .beta.=.sqroot.M.sup.

Abstract: In accordance with the present invention, there is provided a pair of opposing wings for providing aircraft directional stability of a delta-shaped aircraft having a longitudinal axis. Each wing is provided with a substantially straight swept-back leading edge. Each wing is further provided with a lower surface which extends aft from the leading edge. A lower airflow channeling portion is formed into the lower surface. The lower airflow channeling portion is generally elongate and concave and is disposed substantially parallel to the longitudinal axis of the aircraft for channeling airflow substantially parallel thereto.

Abstract: A leading edge structure of an aircraft airfoil including an outer skin, a front wall extended in the spanwise direction of the leading edge structure in a front section of the space defined by the outer skin so as to form an anti-icing duct together with a front part of the outer skin, and a plurality of ribs disposed in the space defined by the outer skin so as to form hot air passages. A laminar structure is formed by superposing upper and lower sheets of a superplastic titanium alloy, inserting a pair of core sheets of a superplastic titanium alloy between the upper and the lower sheet, and forming release agent layers in predetermined regions between the sheets.

Abstract: The instant invention generally relates to a forwardly swept wing 10 for an aircraft comprised of a pair of opposed single piece machined aluminum alloy wing boxes 20 and 40. Specifically, the invention provides for a forward swept wing construction utilizing known in the art computer numerical control machining techniques to produce an aluminum alloy wing 10 having an integral leading edge 24 thereby greatly reducing assembly time. A plurality of integral stiffeners 80 oriented at a forwardly swept angle of approximately 12 to 13 degrees between forward 62 and rear 64 spars provides for a wing 10 that minimizes the effects of aeroelastic divergence.

Abstract: Several innovative systems for an aircraft, and aircraft incorporating them, are disclosed. Features include inboard-mounted engine(s) with a belt drive system for turning wing-situated propellers; compound landing gear integrating ski, pontoon and wheel subcomponents; pivotal mounting armatures for landing gear and/or propellers which provide a plurality of possible landing gear and/or propeller configurations; and a compound wing structure featuring extendable wing panels that permit the wing span of the aircraft to be nearly doubled while in flight. Aircraft incorporating such features will enjoy several safety advantages over conventional multi-engine aircraft and will be capable of modifications during flight which permit landings on any of snow, hard surfaces (runways) and water.

Abstract: An aircraft structure has an arrangement of aircraft components that provide inherent directional stability for a flight vehicle throughout an angle-of-attack range, even at very high angles-of-attack where conventional means of stabilization are ineffective. Components attached to an aircraft fuselage include a wing, horizontal stabilizers and vertical stabilizers. The wing is mounted forward of the horizontal stabilizers and is carried high on the fuselage. The horizontal stabilizer is mounted toward the rear of the aircraft and is attached near the bottom of the fuselage. The wing and horizontal stabilizers are joined on either side of the aircraft by forwardly sweeping aerodynamically shaped surfaces serving as the vertical stabilizers. The inclination of the vertical stabilizers preferably ranges from 45 degrees (top edge canted outboard) to 90 degrees (panels vertical).

Abstract: A novel concept for a wing or airfoil incorporates the model of the natural wave behavior. The leading edge of the airfoil is parallel to the trailing edge, but offset by a given amplitude. The surfaces between the leading and trailing edges are rounded so as to promote proper fluid sheet formation along the surface and to reduce undesirable vortice formation. Best results are obtained by modeling the surfaces along a sine or tangent function.

Abstract: An airplane having a fuselage (11), opposed main wings (12), and blunt-leading-edge raked wingtips (8) is provided. Each main wing includes an outboard end (9) and a leading edge (14) having an outboard end leading-edge nose and nose radius. One blunt raked wingtip (8) is located at each main wing outboard end (9) and includes a leading edge (20) swept back from the main wing leading edge (14). Each blunt raked wingtip (8) further includes a plurality of local airfoils each having a leading-edge nose radius and a chord. The nose radius is greater than about 2% of the local chord for the majority of the airfoils. The relative bluntness of the raked wingtips minimizes boundary-layer separation, drag associated with boundary-layer separation, and premature buffeting of the aircraft during low speed flight.

Abstract: In accordance with the present invention, there is provided an aerodynamic control system which is attachable to an aircraft body and is operable between enhanced control and radar evasive modes. The aerodynamic control system is provided with an aerodynamic support structure which extends from the aircraft body. The support structure is rotatably attached to the aircraft body about a support structure rotational axis. The support structure has an outboard support and an inboard support which is disposed adjacent the aircraft body. The aerodynamic control system is further provided with an elongate torque member which extends from the aircraft body. The torque member has a torque rotational axis which is co-linear with the support structure rotational axis. The torque member further has an outboard end which is fixedly attached to the outboard support of the support structure. In the normal fight mode the inboard and outboard supports cooperatively rotate in response to rotation of the torque member.

Abstract: An inflatable wing containing high pressure inflated spars incorporates open cell foam filling the space within the wing. The foam inflates to a shape in tension which defines the surface contour of the wing. An inflated tube, similar to the spars, is used as a torque tube to actuate the control surface of the wing.

Abstract: A single-cast, thin wall structure capable of withstanding impinging gases at temperatures of 4300.degree. F. and higher, and method of making the same.

Abstract: An air vehicle defining a plane of symmetry includes a pair of outboard panels which are rotatably mounted on the lifting body of the vehicle and respectively extend in opposite directions from the plane of symmetry. A control system collectively rotates the outboard panels to selectively contribute forces from the panels to the lift on the air vehicle. The control system also differentially rotates the outboard panels to control roll of the air vehicle. A pair of empennage panels are also rotatably mounted on the lifting body to establish a dihedral angle centered on the plane of symmetry. The control system collectively rotates these empennage panels to control pitch, and differentially rotates the empennage panels to control yaw, of the air vehicle. In a high speed flight regime the lifting body alone is sufficient and the outboard panels are collectively rotated to reduce drag and contribute substantially zero lift.

Abstract: A large transport aircraft, for more than 400 passengers, with a first wing (3) extending from an intermediate point on the fuselage (1) and a second wing (4) extending from the rear of the fuselage, in proximity to the fin (2). The first wing comprises two halfwings (3a, 3b) swept backward, while the two halfwings (4a, 4b) of the second wing (4) are swept forward. The first and second wings lie on two vertically spaced planes and are connected to one another by respective aerodynamic surfaces (5a, 5b) rigid in their plane in correspondence with the respective halfwings lying on the same side of the fuselage. The first wing (3) can be either at a higher level than the second wing (4) or at a lower level.

Abstract: A method of reducing the effects of induced drag on a foil. A foil is provided with a series of steps along its span in the trailing edge, whereby a series of spaced vortices is generated. The spanwise spacing of the steps is selected so that the vortices are prevented from combining into a larger vortex at least until the aerodynamic effect of the larger vortex on the foil is insignificant.

Abstract: A jet airplane capable of supersonic flight has airfoils with leading edges. Each leading edge has a cavity which extends for substantially the entire length of the airfoil. The leading edge also has a cover which is approximately the same size as the cavity. The cover has an open position and a closed position. When the cover is in the open position, the leading portion has a concave profile. When the cover is in the closed position, the leading portion has a convex profile that gives the airfoil a conventional shape. The cover is rotated to the open position when the airplane reaches supersonic speed. At supersonic speed, a shock wave forms on the leading edge of the airfoil. However, the cavity forms a compression zone between the shock wave and the leading edge, diverting the heat and pressure of the shock wave away from the airfoil. Downstream from the compressed zone, pressure wakes form along the airfoil and cool the airfoil.

Abstract: Methods for using tip generated vortices to improve performance of foils. These methods include generating a substantially streamwise beneficial vortex (74) near the outboard end (60) of a foil (82). This beneficial vortex (74) spins in the opposite direction of an induced drag vortex (62), and is used to create an upwash field (76) which neutralizes induced drag by deflecting the flow behind the trailing edge (56) at an upward angle. Upwash field (76) causes the lift vector (118) on the foil (82) to tilt forward, thereby creating a forward directed force of induced thrust upon the foil (82). Beneficial vortex (74) is also used to contain and compress the high pressure field existing along the attacking surface of the foil (82), and displace the induced drag vortex (62) inboard from the tip of the foil (82). Numerous performance parameters are improved dramatically by using beneficial vortex (74), as well as by using a double vortex pattern (124).

Abstract: A lifting body moves relative to a fluid, thereby creating a vortex field in the fluid downstream of the lifting body. The lifting body has a predetermined lift distribution along the length thereof which enhances the velocity component of the fluid flow directed outwardly from the centroid of the vortex field to reduce the strength of trailing vortices. In a preferred embodiment, the lifting body is a wing with a perturbation proximate to the tip end of the wing planform trailing edge.

Abstract: A method of construction to make military craft and weapons totally invisible to radar and active infra-red by the configuration of exterior surfaces, each surface having that specific surface figure which causes the reflected electromagnetic emission to be convergent to a point, and to be as small a return beam as possible at the distance of the detection device from the craft using the invention.

Abstract: An improved airfoil using bicambered surfaces to promote laminar flow, attached flow, reattachment of flow, delayed flow separation and to achieve high angle-of-attack performance. Bicambered surfaces introduce alternating favorable and adverse pressure gradients to achieve enhanced flow control.

Abstract: A rotary-wing blade of a rotary-wing aircraft has an airfoil section which has an asymmetrical region of positive camber from its leading edge to its approximately 30-percent chord length point and an essentially symmetrical airfoil region from its 30-percent chord point to approximately its 90-percent chord length point. The region aft of the 90-percent chord point can be optionally curved or reflexed upward or downward to a limited degree. This blade has a large lift coefficient and a small pitching moment and is readily adaptable to meet various design conditions of lift coefficient and pitching moment.

Abstract: An improved trailing edge configuration for a transonic airfoil is disclosed. The upper and lower surfaces converge without diverging over the aft 40% of the airfoil chord, and the airfoil has significantly increasing downward curvature at the aft end. The absolute value of the negative slope of the camber typically increases by at least 50% over the aft 4% of the chord, usually increasing by a factor of about 2. The negative slope of the camber of the airfoil typically reaches at least about -0.25 at the trailing edge of the airfoil, and in preferred designs, the slope of the camber changes from about -0.175 to about -0.325 over the aft 4% of the chord.

Abstract: The invention is a natural flow wing and a method for constructing the same. The method comprises contouring a three-dimensional upper surface and a three-dimensional lower surface of the natural flow wing independently of one another into a prescribed shape. Experimental data and theoretical analysis show that flow and pressure-loading over an upper surface of a wing tend to be conical about an apex of the wing, producing favorable and unfavorable regions of performance based on drag. The method reduces these unfavorable regions by shaping the upper surface such that a maximum thickness near a tip of the natural flow wing moves aft, thereby contouring the wing to coincide more closely with the conical nature of the flow on the upper surface. Nearly constant compressive loading characterizes the flow field over a lower surface of the conventional wing.

Abstract: The spiroid-tipped wing, in its basic form, comprises a wing-like lifting surface and a spiroidal tip device (i.e., spiroid) integrated so as to minimize the induced drag of the wing-spiroid combination and/or to alleviate noise effects associated with concentrated vorticity wakes that trail from lifting surfaces. The ends of the spiroid are attached to the wing tip at approproate sweep and included angles to form a continuous and closed extension of the wing surface. For a fixed wing aircraft the spiroid configuration on the right side is of opposite hand to that on the left side. The spiroid geometry incorporates airfoil cross sections with specified thickness, camber and twist. The airfoil thickness varies in relation to the local sweep angle being a minimum at an intermediate position where the sweep angle is zero. The camber and twist vary approximately linearly and change sign at some intermediate position between the spiroid ends so as to produce the optimum spiroid loading.

Abstract: A "fish-shaped" hydrofoil section and in particular, a hydrofoil section having a body of cross-sectional area increasing in thickness from the leading edge to a point near the midchord of the hydrofoil section. The thickness of the body then decreasing some amount to a local minimum, and thereafter increasing along concave surfaces in a "fishtail" flare to a local maximum thickness at the trailing edge. A low pressure area develops behind the trailing edge of the "fishtail" flare and is ventilated with gas at a pressure greater than that of the developed low pressure area. The cross-sectional shape of the hydrofoil section can be symmetrical or cambered.

Abstract: A highly tapered wing tip extension added to the tip of an existing swept, trapezoidal airplane wing for reducing high speed drag significantly. A smaller, highly swept, extension does not require a leading edge device to protect against low speed stall. A larger, less swept, extension requires a tapered slat for which two mechanisms are presented. The principles of the present invention are also applicable to the design of new aircraft.

Abstract: A reduced-drag, axially symmetrical missile or submarine hull with rounded, tapered bow and stern portions, and a rounded central portion tapered, for drag minimization, along a curve defined by a Fredholm equation of the second kind framed so that the pressure coefficient remains constant at all points on the central portion. The missile is designed to travel within a fluid so that its drag coefficient is decreased, boundary layer detachment is avoided, and cavitation and instability phenomena are eliminated. The constant pressure coefficient is reached by following as a profile the natural track lines of the front portion which are joined to the rear portion.

Abstract: A system is disclosed wherein two or more lifting surfaces of an aerodynamic, hydrodynamic or other fluid dynamic device may be linked into a single system that in some circumstances improves the functioning of the device. An important species of the invention is the "Slave Tandem Freewing" airplane--an airplane with two flying surfaces (a wing and tail) both of which are free to rotate about a spanwise axis but are linked together in rotation by a linkage mechanism. Such an airplane exhibits significant improvements in performance and handling including attentuated responses to atmospheric turbulence, freedom from stall and spin, and higher than customary maneuverability. The same device may be built as submarine, boat or other fluid dynamic device.

Abstract: Hydrofoil families which have high lift and low drag coefficients. Induced vorticity is partly suppressed by introducing a longitudinal component of the flow directed from the foil tip towards the hydrofoil base at least in the area of the hydrofoil tip. Further increase of the hydrofoil efficiency is attained by reducing the low lift and high drag induced vortex enhancing area along the tip. For given lift requirements the foil area can be reduced and cavitation performance improved. High torsional and bending resistance are attained by using high modulus materials arranged in chosen directions.

Abstract: A family of airfoils for use in a high solidity factor blade having a leading edge portion and a trailing edge portion, a tip portion, and a root portion, has a plurality of airfoil sections. Each section has: one of any of a plurality of camber lines extending from the leading edge portion to the trailing edge portion, the camber lines being scalable relative to each other, each having the same relative shape, the camber lines having a minimal slope from the leading edge to about a 40% chord and an apogee at about a 74% chord; a scalable thickness ratio of between about 2% to about 7.5%; and, a maximum thickness position which is located from about a 37.5% chord for an airfoil at the tip portion of the blade to about a 35.0% chord for an airfoil at the root portion of the blade.

Abstract: A special contour near the trailing edge of an airfoil which improves the airfoil effectiveness. The contour is a combination of a blunt airfoil base, a local region of high surface curvature, typically on the airfoil lower surface, and upper surface and lower surface trailing edge slopes that diverge from each other.

Abstract: Wing sections, in particular aircraft lift-wing sections, with a section contour where the curvatures in the supersonic flow areas at the top and bottom sides of the section vary as little as possible and where each area is followed by a recompression region with a pronouced maximum of curvature and with tightly spaced inflection points therebehind, a flow gap being selectively settable and located behind the recompression area of the top side of the section.

Abstract: A nacelle wing combination wherein said nacelle can be mounted below the wing and positioned closely to the wing, without creating excessive nacelle induced drag. The wing is contoured so that peak low pressures below the wing occur near the mid chordwise location at the lower surface of the wing. Thus, the channeling of air passing over the nacelle and under the leading edge of the wing does not create supersonic velocities which would create excessive drag.

Abstract: A laminar flow control aircraft wing combines suction surfaces and slots in its leading and trailing edge regions, with natural laminar flow over its main box region to achieve laminar boundary layer flow over a majority of the wing surface area. The wing includes a leading edge flap that is used to protect the leading edge region of the wing from insect accumulation and surface erosion caused by the impact of dirt, rain, or other airborne materials when the leading edge flap is deployed in a low-speed position. At high aircraft speeds, the leading edge flap is stored in the surface of the leading edge region of the wing and forms part of the suction system for that area of the wing. The wing also includes a flexible trailing edge suction surface spoiler system that allows the spoilers to bend either upwardly for lateral control or downwardly when the trailing edge flap is deployed into a low-speed position.

Abstract: An airfoil has a plurality of spaced apart, U-shaped troughs in either or both its suction or pressure surface in the trailing edge region. Each trough extends in a direction generally parallel to the bulk fluid flow in its vicinity near the airfoil surface and has an outlet at the trailing edge. The troughs increase in depth from their inlets toward their outlets, the maximum depth being no more than half the trailing edge thickness. The troughs are spaced apart, sized and configured to flow full over their entire length and to cause fluid to flow into the space immediately behind the trailing edge, thereby reducing base drag.

Abstract: An improved nacelle is provided for housing an aircraft engine and reducing aerodynamic drag during aircraft operation. In one embodiment, the nacelle houses a gas turbine engine and comprises a leading edge and a trailing edge, having a reference chord extending therebetween, and an outer surface which is continuous from the leading edge to the trailing edge. The outer surface includes a forward portion, an intermediate portion and an aft portion that has a profile defined by a varying thickness measured perpendicularly from the chord to the outer surface. The profile has a maximum thickness at the intersection of the forward and intermediate portions, which intersection is located greater than about 36% of the chord from the leading edge, and is effective for increasing laminar flow over the nacelle for reducing aerodynamic drag.

Abstract: An ultralight aircraft having a generally rectangular, swept-back, single-surface wing. The wing, which is formed by fabric mounted on exposed spars and ribs, has a reflex profile to provide pitch stability which is further augmented by horizontal stabilizers projecting rearwardly from the wing adjacent the tips. Roll and yaw control are provided by a pair of rudders pivotally mounted at each wing tip. The forward ends of the rudders pivot inwardly to alter the magnitude of the wing's lift. The rudders pivoted simultaneously act as spoilers and speed brakes controlling the rate of descent. Pivoting one of the rudders individually moves the center of lift for one wing inwardly and increases the drag of that wing to roll the aircraft into that wing. The rudders tilt upwardly and outwardly in a dihedral configuration to provide roll stability. Stationary end plates mounted at each wing tip adjacent the rudders provide yaw stability.

Abstract: This invention relates to airfoils which have particular application to rotors of helicopters and rotorcraft and to aircraft propellers. Two airfoil profiles, the RC(4)XX and RC(5)XX are shaped to permit (1) the development of high air loads without causing an extensive separation of the boundary layer air, (2) a distribution of airloads which results in a near zero pitching moment coefficient about the quarter chord for a range of lift coefficients from -0.2 to 1.0 for Mach numbers up to 0.63, and (3) the development of a local supersonic flow field which is so shaped that the wave losses are minimal until higher free stream Mach numbers over a range of lift coefficients from 0.0 to 0.30. Thus, both airfoils have high maximum lift coefficients, low pitching moment coefficients, and high drag divergence Mach numbers to result in improved rotor or propeller performance. The two invention airfoils are related in shape and purpose.

Abstract: The manoeuverable supercritical wing section with a t/c ratio of 8-9%, flexible at 70%-80% chord by means of a flap to induce expansion thereover, and perhaps having a minimum curvature region on the upper surface just ahead of the flexing region.

Abstract: This invention relates to a transverse driving body, particularly an aircraft wing, the wing comprising a wing tip extending basic parts of the wing in the span direction for the purpose of increasing the aspect ratio, the wing tip being of triangular design with a sweptback leading edge, and the profile camber of each of the wing tip increasing at least over a portion of the extension thereof from a basic wing part to the wing tip.

Abstract: An airfoil (10) having improved life capability and having airfoil curves including a camber divided into three regions I, II and III. Region I has a starting point aft and adjacent a leading edge (12) and encompasses the airfoil stagnation point. Region I has a high curvature around the leading edge and decreases aft along the chord to a first local minimum value of less than 3 for K times C, where C is the length of the chord and K is the reciprocal of the local radius of curvature. The curvature region II starts at the after end of region I within 10% of the chord length and the curvature in region II first increases from the first local minimum at the aft end of region I and then decreases to a second local minimum within 40% of the chord length.

Abstract: The external part at least of a propeller blade, having a maximum relative thickness between about 2 and 6%, has a profile whose thickness variation law along the chord comprises a first zone (I) going from the leading edge to about 8% of the length of the chord in which the curvature decreases rapidly, from a maximum value at the leading edge, followed by a second zone (II) extending between about 8% of the chord and midships in which the curvature decreases linearly. In a third zone, extending from midships to 75 to 85% of the chord, the curvature is substantially constant. A fourth zone (IV), extending from the end of the third zone (typically at 80% of the chord) to the trailing edge, comprises a curvature inversion.

Abstract: An airfoil member having an upper surface contoured to create lift. The lower airfoil surface has a lower forward surface portion which, in a rearward direction, curves concavely into an expanded convexly curved lower surface belly portion. This enables a primary load carrying member (e.g. a spar) to be located in the belly section and have a relatively greater depth, without unnecesary sacrifice of aerodynamic performance. In another embodiment, both the upper and lower surfaces of the airfoil are contoured with the expanded belly portion.

Abstract: An aircraft is disclosed as having the components of a high wing airframe, a single engine of the 360 type, and a propeller formed with airfoil cross sections along the blades thereof having profiles which, when particularly matched with the designated engine and type of aircraft, result in superior performance than is available when any of the components is matched with other components. Specific disclosures of the front and rear cambers of the blades provide aerodynamic characteristics which optimize the performance capabilities of the high wing airframe in conjunction with the designated engine.

Abstract: This invention is for a passive laminar flow airfoil which has an upper skin 12 and lower skin 14 joined at a trailing edge 16. A leading edge structure 20, such as de-icing equipment, is joined to the upper and lower skins by interface mechanisms 30 and 35. Generally, the interface mechanisms are forward facing steps, with or without adjacent gaps, shaped and dimensioned to accomplish laminar flow using standard airfoil manufacturing techniques.

Abstract: A swept wing for jet transports having a thickness-chord length (t/c) ratio that continuously decreases (i.e., tapers) from the wing root to the wing tip is disclosed. The tapered t/c ratio wing has reduced weight and improved overall efficiency when compared to conventional, constant t/c ratio wings. While the t/c ratio of the wing tapers, the combined structural and skin strength of the wing remains adequate to handle bending loads imposed by lift and engine weight. In this regard, the cross-sectional thickness of the midspan region of the wing is chosen such that the wing skin thickness can be reduced to the minimum allowable for the skin material. Also, the cross-sectional thickness of the outboard region of the wing is decreased, resulting in decreased drag and weight in this region. Further, the camber of the outboard portion of the wing is increased (as compared to the camber of a constant t/c ratio wing) to prevent the unsweeping of spanwise oriented isobars.

Abstract: A wing-section design for lift-wings, for instance for fighter aircraft, where the section design specifically depends on specially designed top and bottom sides of the section and where the top side curvature along the depth of section depends only upon the operational Mach number, while the bottom side curvature additionally depends on the section thickness and the desired lift range.

Abstract: An airfoil used in a ruddevator assembly for controlling movement of an aircraft refueling boom, where there are two airfoils (i.e. ruddevators) mounted to the boom, each at a dihedral angle of about 42.degree.. Each airfoil has an outboard section, which is an advanced technology cambered airfoil for high lift at transonic speeds, with a raked wing tip. The inboard portion of the airfoil has a forwardly extending strake-like member having a sharp leading edge which in planform comprises three sections. There is a curved forward edge section and two rearwardly extending edge sections, which in operation are positioned at high sweep angles. The side edge portions of the strake-like member create vortices which travel over the inboard portion of the airfoil to augment lift over a wide range of surface deflection of the airfoil (i.e., angle of attack).

Abstract: Profile design for aircraft lift-wings in general aviation up to flight speeds of about 700 km/h, the profile design being determined by the path of the center line with a forward (first) and rear (second) camber maximum and with a profile droplet superposed on the center line and of a specific thickness distribution, and by the design of the profile nose to have a relatively small nose radius and relatively strong camber.