Abstract: A perforated sheet is diffusion bonded to a thin solid sheet. Each of the perforations of the perforated sheet is tapered, having a maximum diameter at the surface that is not bonded to the thin sheet and a smaller diameter at the surface that is bonded to the thin sheet. The bonded perforated sheet and thin sheet are included with other solid metallic sheets in a forming pack to be superplastically deformed into a structure. The bonded perforated sheet and thin sheet are placed on the top of the forming pack so that the thin sheet will face outwards after the structure is formed. After the superplastic deformation process is completed, the thin sheet is removed by machining to expose the perforated sheet and provide a structure for controlling laminar flow over the perforated sheet. The exposed surface of the perforated sheet includes the smaller diameter of each tapered perforation, while the inner-facing or blind surface of the sheet includes the maximum diameter.

Abstract: The present invention pertains to an aircraft that is capable of converting between vertical flight or helicopter mode flight, and horizontal flight or airplane mode flight where a two-bladed rotor is employed as both helicopter rotor blades in vertical flight and as a fixed wing in horizontal flight. In vertical flight, a bearing connection between two fuselage sections enables a forward section supporting the rotor blades to rotate relative to an aft section of the aircraft fuselage about the longitudinal axis of the aircraft. The exhaust or thrust force created by the mode of power (either a propeller engine or a turbine jet engine) is partially routed over the exterior of the aircraft to provide both vertical and horizontal thrust force, and in one embodiment a portion of the exhaust is routed through the interiors of the rotor blades and out exhaust ports at the blades' distal ends to rotate the blades in vertical flight and to provide a thrust force for the blades in horizontal flight.

Abstract: The lower lip of an aircraft inlet cowl has a first transverse slot formed through an upper surface of the lower lip while a second transverse slot is formed through a lower surface of the lip. A rotating vane is transversely located in the interior of the lip, between the upper and lower slots. A duct located within the interior of the lower lip delivers pressurized engine bleed air to the rotating vane. Selectively driven gears position the vane so as to block either one or the other of the slots, depending upon aircraft speed, so that normal cowl inlet air is energized in the vicinity of the slot outlet. This prevents separation of the normal inlet airflow from the cowl surface - and reduces drag that would otherwise develop.

Abstract: A blown boundary layer control system for an aircraft having a jet engine with an engine compressor, an inlet including a compression surface with an external part and internal part, a cowl lip including an internal lip surface and an external lip surface and an external afterbody. The system includes several ducts from the engine compressor. A series of nozzles and valves control and direct air flow to various surfaces. A computer is electrically connected to the valves to control the operation of the valves thereby controlling the blowing of air from a commanded number of nozzles. The computer controls the valves in position as functions of RPM of the engine, free stream flight conditions and aircraft attitude.

Abstract: An aircraft wing having a super critical profile is equipped with a venting device extending in the direction of the span width along the upper side of the wing. The ventilating device includes a compensation chamber in the wing and the chamber is covered with a perforated wall strip on both sides of the compression shock. The forward end of the compensation chamber has a gap shaped exit for blowing out the venting medium in the flow direction of the flow across the wing tangentially to the wing.

Abstract: A method and apparatus for establishing discrete zones of pressure at the surface of a perforated panel of the type typically used for laminar fluid flow control includes a first array of channel members fluidly communicating with perforations in the panel, all of the channel members in the first array extending in a first direction and being substantially parallel to one another, and a second array of channel members fluidly communicating with the fluid in the first array of channel members, all of the channel members in the second array extending in a second direction and being substantially parallel to one another, where the first and second arrays of channel members being disposed in crossing relationship with a source of pressure being applied to the second array of channel members. By this arrangement, control of fluid flow in at least one of the first and second arrays results in discrete zones of pressure at the surface of the panel.

Abstract: A pair of spaced slots, disposed on each side of an aircraft centerline and spaced well inboard of the wing leading edges, are provided in the wing upper surfaces and directed tangentially spanwise toward thin sharp leading wing edges of a highly swept, delta wing aircraft. The slots are individually connected through separate plenum chambers to separate compressed air tanks and serve, collectively, as a system for providing aircraft lift augmentation. A compressed air supply is tapped from the aircraft turbojet power plant. Suitable valves, under the control of the aircraft pilot, serve to selective provide jet blowing from the individual slots to provide spanwise sheets of jet air closely adjacent to the upper surfaces and across the aircraft wing span to thereby create artificial vortices whose suction generate additional lift on the aircraft. When desired, or found necessary, unequal or one-side wing blowing is employed to generate rolling moments for augmented lateral control.

Abstract: An aircraft may have vertical take-off and landing capability including a power-generating mechanism, a propulsion-developing mechanism, and laterally extending wings. Each wing includes an aerodynamically composite airfoil having a lower camber possessing an aerodynamic thrust-flap. A rotor is provided at the free end of each wing for rotating in a plane parallel to the plane of the wing. The lower surface of each wing includes thrust flap aerofoils which may be moved to shape a convergent-divergent nozzle and with the cooperation of the rotor to produce thrust. The rotor is driven by a wing turbine embodied in the wing. Any combination of different power plants provides the initial stage of compressed air to the wing turbine and/or motive fluid.

Abstract: A STOL aircraft includes propfan engines which are each connected to a lower surface of one of the wings by a pylon. The propfan engine is located directly below the wing and are each equipped with fans at a rear portion thereof. A slat is connected to a leading edge of the wing and not divided by any object, including the pylon and the propfan engine.

Abstract: Apparatus and method for attenuating fluid foil tip vortices, featuring a "Coanda tip" and a "Coanda curtain." The fluid foil tip has a Coanda surface and means for discharging compressed fluid adjacent thereto; a resultant fluid barrier is formed generally chordwise and perpendicular to the fluid foil plane and tangential to the fluid foil tip upon Coanda entrainment and deflection of the discharged compressed fluid. The fluid barrier prevents crossflow from the higher pressure fluid region to the lower pressure fluid region, the fluid regions being separated by the fluid foil when moving relatively through a fluid, the fluid barrier thereby stemming tip vortex generation at its source.

Abstract: Methods of and apparatus for controlling the separation of a boundary layer from a surface on which an adverse pressure gradient exists. A streamwise jet of fluid is so discharged onto the surface at a location adjacent the juncture between the surface and an adjoining structure as to energize the boundary layer and thereby delay the separation of the boundary layer from the airfoil in the vicinity of that juncture.

Abstract: In an aero-optical interface for an aircraft optical aperture, the separation of the upstream boundary layer from the edge of the aperture creates a region of turbulance which persists downstream over the full area of the aperture. This invention promotes an early develpment of a steady velocity profile at the upstream aperture edge which is approximately the same as a stable, self-similar shear flow velocity profile over the entire aperture. This is accomplished by thickening the boundary layer upstream of the aperture, and blowing a curtain of air across the aperture from its upstream edge at the point of separation of the boundary flow. This produces a shear flow region foot that causes the overall velocity profile to be equal to a stable self-similar free shear layer.

Abstract: A process for reducing skin friction, inhibiting the effects of liquid turbulence, and decreasing heat transfer in a system involving flow of a liquid along a surface of a body includes applying a substantially integral sheet of a gas, e.g., air, immediately adjacent to the surface of the body, e.g., a marine vehicle, which has a longitudinally grooved surface in proximity with the liquid and with a surface material having high contact angle between the liquid and said wall to reduce interaction of the liquid, e.g., water, with the surface of the body, e.g., the hull of the marine vehicle.

Abstract: A vertical takeoff ultralight aircraft having an operator controlled high volume vane axial fan in communication with a conduit configured to direct an air stream produced by the fan to a spanwise air duct disposed forwardly of a wing including an air foil. High velocity air is discharged from the air duct and directed over the upper surface of the air foil. An induced air stream flows upwardly and rearwardly through an air flow path defined by the spanwise air duct and the air foil. The wing and air duct are configured such that the induced air stream joins the air stream discharged from the air duct to create reduced static pressure zone on the upper surface of the wing of sufficient magnitude to effect vertical lift. Fan discharge may be partially deflected rearwardly to provide horizontal thrust.

Abstract: A thrust-producing device comprises a body having a surface and a periphery and disposed in a first fluid; a generator for imparting energy to a second fluid; and a distributor connected to the generator, disposed adjacent the surface, for distributing the second fluid in a first stream over and adjacent the surface for blanketing and enclosing at least a portion of the surface with the first stream and causing the first stream to be initially sufficiently unattached to the surface to define a closed volume between the surface and the first stream.

Abstract: A basic airfoil has its operating performance improved by incorporating one or more apertures in the airfoil adjacent its trailing edge. These apertures extend from the upper surface of the airfoil down through to the lower surface of the airfoil. The entry port and the exit port of these apertures has a greater circumference than that of the throat circumference which is intermediate thereto. This structure forms a venturi having a vertical axis. Spaced below the throat of the aperture are a plurality of air nozzles that communicate with an air plenum chamber within the airfoil. A source of pressurized air is connected to the plenum chamber. The leading edge of the airfoil causes air to flow across both the upper surface and lower surface of the airfoil. The venturi creates a strong suction on the upper surface of the airfoil to enhance the airfoil's pressure differential.

Abstract: An aerofoil or hydrofoil (1) has a vessel (2) for providing a high velocity jet of fluid directed from a nozzle (3) in a direction having a component of velocity in the same direction as the required direction of lift (L). The aerofoil or hydrofoil (1) also has a curved surface (5) convex on the side of the aerofoil or hydrofoil which is in the direction of the required lift, and which serves to direct the velocity of the jet in a direction which is substantially opposite to the direction of the required lift or thrust force, the primary jet being directed over the convex surface for attachment thereto; and a duct formed over a rear part of the convex surface remote from the nozzle, whereby the primary jet of fluid flowing over and attached to the convex surface causes an enhanced flow through the duct, the duct being directed at least at its exit end in a direction so that the flow therethrough has a component of velocity opposite that of the required direction of lift.

Abstract: A pair of integrated water propulsion and hydrofoil systems capable of moving through water at speeds of at least 20 miles per hour are disclosed, each hydrofoil system having a hydrofoil and a mounting leg removably secured to a water propulsion system. The mounting legs are supported on opposite sides of the watercraft for moving the hydrofoils between a water mode and a land mode. The water propulsion system may be an inline water jet, and the hydrofoils may be formed from interconnected lightweight hollow beams with power operated flaps on the trailing portions of the hydrofoils for adding more lift when moving at slow speeds through water. The watercraft may be a military amphibious vehicle weighing about 30 tons.

Abstract: A method and apparatus for eliminating heat build-up caused by air friction on wings and other air foils, especially common in high-speed aircraft. As an aircraft is moving, a small portion of air in the airstream moving by the wing or other air foil is passed through an air intake valve on the wing, into a Venturi section and then into a chamber within the wing or frame where the air is compressed naturally. Each Venturi section consists of a converging and diverging nozzle which creates a substantial cooling effect when the high speed air passes through it and is compressed and released. The intake valve spins or flips when hit by the airstream so it alternately intakes and exhausts the air through the Venturi section, thereby causing a double cooling effect. A second embodiment uses valves, one on the leading edge for air intake and the second near the back of the lower surface of the wing for air exhaust.

Abstract: A low drag surface comprises at its upstream edge, an intermittent linear vortex producing means which extends transverse to the flow over the surface and produces a succession of rolling vortices extending transverse to said flow. The vortices move across the surface and reduce drag in the manner of roller bearings. In preferred embodiments the vortex producing means is mechanical, in the form of an oscillating part or fluid dynamic, in the form of a nozzle arrangement.

Abstract: A method and apparatus for reducing the skin friction on objects in relative motion to a field of fluid. The areas of relative low speed motion are fixed to align with a series of ridges on the surface of the object. The areas of low speed motion aligned with the ridges are removed by suction from the turbulent boundary layer which results in a reduction of drag on the object. An alternative embodiment injects fluid into areas of relative high speed between the ridges to reduce the shear and the drag caused by it. Selective suction and injection are combined in one apparatus in a second alternative embodiment. A fourth embodiment injects a polymeric solution to reduce drag. A fifth embodiment heats the fluid in specified areas to reduce drag. A sixth embodiment uses a compliant material in specified areas of the surface in contact with flowing fluid to reduce drag.

Abstract: An engine assembly comprising an engine having an unducted propeller mounted in a pusher configuration. The engine is supported by a mounting strut located upstream of the propeller. The trailing edge portion of the strut discharges air through a rearwardly facing slot to diminish discontinuity of airflow moving from the region of the strut to the propeller, so that load variations on the propeller are diminished, and also improves flow of the intersection of the strut and the fuselage.

Abstract: A wing (2) has a trailing edge at which jet flow is deflected downwardly to provide lift. A retractable member (4, 4') has a sharp forward edge (6, 6'). When deployed, member (4, 4') extends along at least a portion of the span (preferably substantially the entire span) of the wing (2) at the leading edge of wing (2). Member (4, 4') projects forwardly and upwardly from wing (2). Member (4, 4') causes flow around wing (2) rearwardly of itself to separate from wing (2) to reduce suction and leading edge thrust. Preferably, reattachment of flow is induced at a location spaced rearwardly from member (4, 4'). A jet of high velocity gas is blown along wing (2) in a generally spanwise direction. This induces reattachment to maintain trailing edge thrust so that jet deflection at the trailing edge will efficiently provide lift during a short distance landing.

Abstract: A cylindrical roll drum housing (12) is mounted to the roof (18) of an aircraft fuselage. Enclosed in the housing (12) is a sensor (22) that pivots about an azimuthal axis (82). The sensor (22) normally looks outwardly through sliding window (20) that moves back and forth in correspondence with sensor pivoting. Pressurized air is blown directly across the window's opening (40), and is also blown directly into the housing (12). The window (20) has an inwardly directed airflow-deflecting edge which, in combination with the air blowing, is used to control boundary layer vortices across the window's opening so that they do not interfere with sensor properties.

Abstract: A lift enhancing system for an aircraft having wings and a deflectable airfoil attached to the trailing edge of the wing which includes ejecting nozzles attached to and movable with each deflectable airfoil to eject gas spanwise across the surface of the deflectable airfoil and thereby enhance the lift of the wing and deflectable airfoil.

Abstract: A fixed wing airplane having a turbofan engine mounted within its fuselage is equipped with communicating air-handling chambers, and pivoted panels positioned in the upper surfaces of the wings and stabilizers. The arrangement of air-handling chambers and pivoted panels supplies high velocity air through discharge slots tangentially to the upper surfaces of the wings and stabilizers, and air inducting slots on the same surfaces downstream from the discharge slots. Such manner of function causes a boundary layer of air to cling tightly to the upper surfaces, and this effect provides reduced pressure that produces vertical lift. Once in forward horizontal flight, the various components of the airplane function in conventional manner.

Abstract: A gas turbine engine for a compound helicopter comprises a core gas generator, an upstream fan, and a power turbine. Bypass air is selectively directable to either augmentor wings, or to a second power turbine which is mechanically coupled to the first power turbine.

Abstract: A pneumatic aerodynamic control surface is described for an aircraft having a region of upwash ahead of a powered-lift or high-lift wing, the control surface comprising blown engine nacelles immersed in the upwash region, and capable of generating moments about all three axes of the aircraft without any external moving parts.

Abstract: A high performance aircraft capable of subsonic, transonic and supersonic speeds employs a forward swept wing planform and at least one first-and-second-solution ejector located on the inboard section of the wing. A high degree of flow control on the inboard sections of the wing is achieved along with improved maneuverability and control of pitch, roll and yaw. Lift loss is delayed to higher angles of attack than in conventional aircraft. In one embodiment the ejectors may be advantageously positioned spanwise on the wing while the ductwork is kept to a minimum.

Abstract: The surface of the body is provided with grooves (5), which extend in the flow direction and which are separated from one another by ribs (4) which are constructed to have sharp edges. The surface is composed of a multiplicity of individual elements (3), which have the ribs (4) and grooves (5) on their side facing the flow. The individual elements (3) are disposed relative to one another and/or constructed in such a manner that slits are formed on the side facing the flow between the ribs and grooves. The slits (9) are connected with one another by channels (6) disposed below the surface of the individual elements (3) which faces the flow.

Abstract: A leading edge/anti-icing assembly for an airfoil comprising a leading edge slat having a nose section defining a heat exchange chamber. Anti-icing air directed into the heat exchange chamber flows rearwardly through the slat so as to have a deicing function, and is then discharged in a rearward direction from the trailing edge of the slat. Thus, the anti-icing air not only performs an anti-icing function over the upper surface of the slat, but also contributes to anti-icing over the upper surface portion of the main wing rearwardly of the trailing edge of the slat.

Abstract: Air is blown into an air boundary layer to re-energize the boundary layer prior to its ingestion by an engine inlet (12) of a supersonic aircraft (10).

Abstract: A deicing system for leading edges of an aircraft. There is a hot air supply tube extending along the leading edge, a fan to move air through the tube, an electric heater to heat the air that is moved through the tube, and pressure release valves. The hot air is discharged from openings in the tube to spray against the internal surfaces of the wall forming the leading edge. In another embodiment, an electric heater is not used, but there is a compressor which in compressing the air raises the air temperature to accomplish the deicing.

Abstract: A nacelle anti-icing system for a jet engine and a method for preventing icing of the nacelle. The nacelle anti-icing system includes a nose cowling assembly having a nose ring and an inlet duct connected to the nose ring, the nose ring including a plurality of openings formed therein; a nose cowling conduit positioned in the nose ring for communicating a heated gas to the plurality of openings formed in the nose ring and for creating a heated gas boundary layer on the inlet duct, and a mechanism connected to the nose cowling conduit for generating the heated gas. The method includes the steps of feeding a heated gas through the nose cowling conduit and through a plurality of openings formed in the nose ring and generating a heated gas boundary layer on the inlet duct so as to heat the inlet duct.

Abstract: A fluid flow control device controllably maintains attached flow in the region of a body having a contour of rapid curvature utilizing tangential fluid discharge slots, positioned just upstream from the separation line, which issue a thin jet sheet to energize the boundary layer and entrain the surrounding flow. When applied to the aft fuselage of an aircraft, the device reduces separation and vortex drag at cruise and provides control forces and moments during low speed operation of the aircraft.

Abstract: The present invention provides a single seat aircraft having the capabilities of vertical takeoff, landing and hovering operations utilizing the X-Wing as a conventional helicopter rotating wing. After transition to forward flight following takeoff, the rotating wing is stopped and becomes a fixed wing of "X" configuration. The aircraft utilizes two engines within the fuselage, one engine being positioned vertically above the other along the longitudinal axis of the aircraft, the particular arrangement of engines allowing aircraft size and weight to be substantially reduced.

Abstract: A method of applying and controlling vortex lift to a unique high-lift airfoil (29) is described wherein the planform of the airfoil (29) comprises a swept-forward outer panel (31) and a swept-aft or unswept inboard panel (33). A leading edge vortex (37) is formed on (31) and attached flow is maintained on (33). The attached flow on (33) causes the vortex (37) of the airfoil (29) to turn downstream and also induces axial flow along axis of vortex (37). Both of these results serve to delay vortex burst. A high-lift trailing edge device (45) such as a mechanical flap as the circulation control concept will induce a high leading edge flow angularity and cause the vortex (37) to grow in strength, thereby increasing vortex lift. The vortex (37) replaces the high-weight, high-lift leading device that would otherwise be required.

Abstract: A method and apparatus for providing an aero-optical interface by stabilizing a shear layer in a fluid flowing over an aperture. The apparatus extracts fluid from a remote part of the flowing fluid and conveys it to the underside of the shear layer where it feeds the shear layer and prevents the shear layer from deflecting into the cavity underlying the aperture. A preferred embodiment also includes a ramp downstream of the aperture. Stability of the shear layer is optimized by placing the aperture where the pressure distribution absent the aperture would have been constant. The resulting thin, self-similar shear layer is an optimized viscid flowfield interface for uniform transmission of optical radiation.

Abstract: The lift generated by delta wings is due primarily to large vortices associated with the flow separation near the leading edge. The invention includes a perturbation device to control the separation shedding of those vortices and manipulate their frequency and pairing. This results in different growth rates of the vortices downstream of the device and thus the lift produced by the large bound vortices may be controlled. If the invention is applied to both leading edges, the total lift of the wing will be altered; if the perturbation is preferentially applied on only one side of the wing, the moment around the roll axis of the aircraft is controlled. A first embodiment uses a piston coupled to a cavity and slot to produce the desired perturbation. Alternative embodiments are described which achieve the results without moving parts.

Abstract: A compound helicopter shown in FIG. 1 of the drawings has wings 12 in addition to a helicopter rotor 14 and has twin powerplants 16 each including a low pressure compressor 18, a core engine 20, a power turbine 22 driven by the core engine and connected through a gearbox 32 to drive the helicopter rotor, and a variable area final, propulsion nozzle 24 which receives the exhaust from the power turbine. Augmentor wing flaps 28 are provided on the wings and fed with air from the low pressure compressor for providing additional lift and thrust from the wings. In operation, at take-off the nozzles 24 are fully opened and all of the power produced by the power turbines 22 is used in driving the helicopter rotor for producing lift. In addition, the augmentor wing flaps 28 are directed downwardly to provide lift. For forward flight the nozzles 24 are closed down, reducing the power to the rotor and slowing it down, while at the same time generating forward thrust.

Abstract: A control force generator for an aircraft using circulation control to a selectively produce lift on an otherwise non-lift surface. The generator employs a novel, double-slot single Coanda surface arrangement for selectively generating the aerodynamic lift.

Abstract: The duct (16) which delivers hot air (F) to the inside surface of the leading edge of a turbo-fan inlet cowl, for de-icing of the leading edge (11), is made double-walled (16,21) in order to safeguard from overheating the materials from which the cowl is constructed in the event of rupture of the duct. Preferably the flow of hot air in the outer duct blows open a hinged door (26) in the skin (10) of the cowl to provide a visual indication of the rupture of the inner duct. The outer duct can be made narrow enough to maintain working pressure in the inner duct after rupture.

Abstract: An aircraft wing is equipped with at least one low compression fan which blows into a longitudinal flow channel extending lengthwise or spanwise of the wing and leading into air blowing nozzle arranged along the upper wing surface where the reduced pressure is largest for directly mixing the propulsion air jet or jets with the boundary layer air flowing along and adjacent to the upper wing surface. Both, the flow channel and the air blowing nozzles extend substantially along the entire length of the wing for increasing the resulting propulsion force and/or the resulting lift due to the mixing of the propulsion air jet with the boundary layer air directly in the boundary layer.

Abstract: A supercritical movable airfoil over which is blown air to obtain a Coanda affect. A sealing strip is provided on a stationary airfoil portion which seals against the movable airfoil portion during blowing to prevent flow of air therebetween.

Abstract: A sailing rig which comprises a rigid airfoil, with intakes on either side of its front. Air is drawn through the leeward intake into a front compartment, then by fan to a pressurized rear compartment, where it exits via a rearwardly directed jet nozzle on the airfoil's trailing edge. The airfoil may have an articulated jib and a pivotable jet nozzle.

Abstract: Disclosed is a propulsive lift mechanism which improves the short takeoff and landing capabilities of an aircraft by generating transverse thrust lift augmentation by exhausting gasses ported from the main exhaust through a nozzle, close behind and parallel with the trailing edges of the wings of the aircraft, which transverse jet together with thrust vectoring means of the aircraft, provide improved aerodynamic lift on the wings of the aircraft. The transverse nozzle, having means adjustable for creating reverse thrust, and optionally for discharging said exhaust gasses with a swirling motion, may provide both increased circulation of air over the wings as well as improved flow separation control on the trailing edge flaps of the wings. Exhaust gas from the jet engine of the aircraft is ported to the transverse nozzles by flap valves operating in the exhaust of the jet engine.

Abstract: A nozzle system for providing improved thrust augmentation for an aircraft lift and/or propulsion system is provided. The unique nozzle structure is designed such that counter-rotating vortices emanate from the nozzle tips. When this unique nozzle configuration is combined with simple slot nozzles in a specific manner a vortex rich flow will result. When a diffuser is placed around this unique combination such that jet pumping is obtained, significant improvement in thrust augmentation is realized from the vortex rich flow mixing with the coflowing secondary air stream.

Abstract: An arrangement for controlling the air flow past an aerodynamic profile, (such as an aerofoil surface of a wing, tail plane, or fuselage of an aircraft or missile, a propeller, helicopter rotor, or blading of a turbo-engine fan or wind impeller) by providing a number of orifices of small diameter spaced apart in the profile surface in the longitudinal direction of the profile transversely to the direction of air flow over the profile and to the chordwise direction of the profile. Fluid is either discharged or drawn in through the orifices perpendicularly to the air flow in the region of separation of laminar flow. The orifices have a coefficient of flow (i.e., either a discharge or an intake coefficient) C.sub.Q =(V/FV) of up to 10.sup.-4 for a Reynolds Number less than 3.times.10.sup.6, where v=volume flow of the fluid through the discharge orifices, F=profile area and V=velocity of the air stream flowing over the wing or blade.

Abstract: An anti-icing pressurized air distribution duct system for deployable wing slats wherein mutually telescoping transfer ducts interconnecting a longitudinal wing slat spray duct and a longitudinal wing supply duct, with bearing and seal means fixed on the inner transfer duct to bear slidably against the outer duct interior and remaining protected within the outer duct throughout slat extension and retraction.

Abstract: A compound helicopter shown in FIG. 1 of the drawings has wings 12 in addition to a helicopter rotor 14 and has twin powerplants 16 each including a low pressure compressor 18, a gas generator 20, a power turbine 22 driven by the gas generator and connected through a gearbox 32 to drive the helicopter rotor, and a variable area final propulsion nozzle 24 which receives the exhaust from the power turbine. Augmentor wing flaps 28 are provided on the wings and fed with air from the low pressure compressor for providing additional lift and thrust from the wings. The flaps 28 are pivotally mounted on the trailing edge of the wing and are movable to a position where the trailing edges of the flaps 28 obturate the flow through the gap between the flaps 28. In this position the flaps provide a means of decelerating the forward speed of the aircraft.