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: The invention comprises a combination boundary layer control system that utilizes both suction and cryogenic wall cooling to reduce aircraft drag. The invention is particulary useful in circumstances where liquid hydrogen or other cryogenic fuels are used to operate the aircraft.In the preferred embodiment of the invention, a network of D-tube ducts are provided that are fluidly connected to a cryogenic fluid source. These cryogenic fluid ducts are selectively fed cryogenic fluid to reduce aircraft surrface temperature and promote adhesion of boundary layer air to the aircraft. An air duct system is also provided to apply suction to the aircraft surface in order to remove the boundary layer at low altitude. The suction is applied by means of a multitude of minute holes in the aircraft skin which are fluidly connected to the air duct system.

Abstract: A boundary layer control device is installed in the acoustically treated inlet duct of a turbofan engine. The device sucks off the turbulent boundary layer of air flowing over the inner or "air wetted" surface of the inlet during aircraft take-off, cruise and approach. The lip of the inlet can thus be made thinner to reduce drag during cruise without degradation of fan performance during take-off. The acoustic liner of the inlet comprises a microporous honeycomb sandwich structure through which air may be sucked at various locations through headers and conduits connected to an onboard pump.

Abstract: An elongated airfoil is perforated in such a way as to cause boundary layer air at the airfoil surface to be drawn into the airfoil, and then evacuated.

Abstract: An apparatus for controlling flow over a surface, especially transonic flow, including means for embedding within the surface small vortices with their axes parallel to said surface and transverse to said fluid flow, and means for driving said vortices.

Abstract: A combination lift and thrust device for increasing the performance of an aircraft by simultaneously reducing drag and augmenting the thrust of a turbojet engine carried within the device. The device comprises a wing of generally airfoil shape having numerous geometrically spaced apertures penetrating its surface, a turbojet engine carried within the wing, an elongated exhaust plenum attached to the turbojet having a number of strategically positioned exhaust nozzles, and a mixing chamber having a forward opening and a rear nozzle also carried within the wing. The mixing chamber forward opening is cooperatively associated with the exhaust nozzles to form an ejector drawing air through the apertures in the wing into the forward opening, mixing the air with the exhaust gases from the turbojet to provide thrust augmentation, and exhausting the air and gas mixture from the rear nozzle of the mixing chamber.

Abstract: Separated laminar flow boundary layers are stabilized by delaying a transition into a turbulent flow and by reducing the size of the laminar boundary layer separation zone downstream of a disturbance in the surface contour of a body in the flow, such as a backward step in the body surface, e.g., where sheet metal layers overlap in the surface of an aircraft wing. This purpose is accomplished by suction inlets in the surface just upstream of the disturbance and blowing outlets just downstream of the disturbance and by a flow channel interconnecting these inlets and outlets. Passage of a portion of the flowing medium through these passages is automatically assured due to a pressure differential between the inlets and outlets.

Abstract: A supercritical wing of the variety in which the compression shock is stabilized is being improved by providing a suction device, substantially along the entire wing span, right at the chord station of the upper-wing surface where intercepting the sonic line. Specific rules concerning the suction and suction slit are given. A small chord station range may be covered by a movable slot or several parallel-running slots. The surface contour may be modified right at a slot to, thereby stabilize the compression shock further. The invention shifts buffet onset to larger off-design Mach numbers and angles of attack.

Abstract: A sailboat keel structure, wherein the keel has an elongated body with fore and aft edges, and a generally elliptical cross-section. An elongated slotted opening is formed along the aft edge between the upper and lower ends of the keel, with the opening extending forwardly to a point generally aft of the minor axis of the elliptically configured keel so as to create an internal chamber in the keel with an aftward opening. A plurality of bores are formed in the keel and extend diagonally from forward ports along the outer surface of the keel to aftward ports along the inner lateral surfaces of the internal chamber. While the bores may be generally cylindrical in their configuration, they are preferably tapered from a smaller diameter at the forward port to an increased diameter at the aftward port.

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 downwardly when the trailing edge flap is deployed into a low-speed position.

Abstract: The object of this invention is an element, such as a rudder, and aircraft wing, a boat keel, a hydrofoil or an airfoil or the like, which is adapted to move through water or air and which is so designed that the water or the air is allowed to enter at the upstream edge of the element into and through a hollow space within said element and to leave said element at the trailing edge thereof, said hollow space within said element being divided into two halves by a central longitudinal partition (6) within said element, such that said element on either said of the said central partition (6) has a flow gap which, optionally, is divided into parallel passages by transverse partitions (4a, 4b, 5a-5c), the arrangement being such that the flow of water or air through and out of the gap between the central partition (6) and that side of the element which, in response to the angular deflection or profile, forms the suction side of said element, will be substantially larger than through the other gap.

Abstract: A method for manufacturing a laminar flow control aircraft structure, typically a wing or other aerodynamic surface, having an outer skin in which a plurality of spanwise oriented and chordwise spaced recesses have been machined. The method includes the installation of a strip of slot assembly tape in each of said recesses, preferably with an adhesive, and the removal of an element of the tape called a cover plate to expose a spanwise slot through which boundary layer air can be drawn. Also disclosed is a slot assembly tape having a protective cover plate and a pair of sidewalls, and a laminar flow control aircraft structure, typically a wing, in which the slot assembly tape has been employed.

Abstract: A porous aircraft skin for wetted areas of an aircraft employed in conjunction with a suction system of the aircraft to draw air inwardly through pores of said skin for laminar flow control. The porous skin is compliant and includes a thin outer skin with fine pores bonded to a lower substantially thicker coarser pore compliant skin with the thicker skin in turn bonded to the structural skin of the aircraft. Vacuum chambers beneath the aircraft structural skin receive air sucked through the porous compliant skin and through communicating holes of the structural skin. One-way valves of flexible or semi-flexible material are inserted into the suction holes of the aircraft structural skin prior to the placement of the porous compliant skin. Low pressure above the aircraft lifting surfaces automatically closes the one-way valves thereby maintaining low pressure above the lifting surfaces and preventing reverse flow from destroying the lift afforded by said surfaces.

Abstract: A vertical take-off and landing aircraft features an improved tail-lifting rotor and rotor directional controls. A new type of suction pressure jet-mechanical-flap rotor blade with a higher coefficient of lift is employed. The aircraft has a mechanism for loading and unloading passengers and a more efficient method of handling baggage and cargo. A much more efficient utilization of space in the fuselage is achieved through a reduced height passenger space and overhead rotor storage compartment.

Abstract: An aircraft which produces a free vortex to provide the lift for takeoff and landing procedures has a single centrally mounted engine which supplies both the forward thrust to the aircraft and the spaced pumping action for strengthening and maintaining the free vortex. A shield on the aircraft causes the shedding of vorticity into a cavity-like region behind the shield. A vortex guiding duct extends transversely beneath the aircraft frame and has a pair of inlet openings at the ends of the cavity region. A thruster duct extends longitudinally centrally of the frame and communicates with the vortex duct. An engine is mounted in the thruster duct and supplies forward thrust for the aircraft while simultaneously pumping air from the ends of the cavity region through the vortex duct. This pumping action retains, augments and concentrates the vorticity and results in the formation of a generally circularly-shaped free vortex stretching transversely across the cavity region and through the vortex duct.

Abstract: Disclosed is an increased lift aircraft or similar device having an airfoil shaped forward structure. A mass flow engine, such as a jet engine, is positioned to the rear of this structure. In operation, the intake air flow for the engine flows around the forward structure, generating lift.