A vehicle includes a surface for contacting a fluid medium through which the vehicle is propelled. The vehicle also includes an array of transducers and a controller. The transducers in the array are arranged across the vehicle's surface for generating pressure waves in the fluid medium. Each transducer in the array is arranged to vibrate for generating a respective pressure wave, which propagates away from the surface in the fluid medium. The controller vibrates the transducers in the array so that the pressure waves control the drag of the vehicle from the fluid medium.

An aircraft (5) including an aerodynamic surface (6), an aerodynamics improvement device with a first electrode (27) embedded beneath and electrically isolated from the aerodynamic surface (6), a second electrode (28) electrically isolated from the first electrode (27), a voltage generator (30) adapted to apply a voltage between the first and the second electrode, further comprising a layer of electrically insulating material (26) between the second electrode (28) and the aerodynamic surface (6). Methods for detecting ice on and de-icing an aerodynamic surface (6), and for delaying a boundary layer transition and separation from the aerodynamic surface.

Shield assemblies for an aircraft landing gear include an aerodynamic shield, a first support bracket assembly, and a second support bracket assembly. The first support bracket assembly is configured to couple with a structural member of the aircraft landing gear, to support a first end of the aerodynamic shield, and to have a first position that is fixed relative to the structural member in an x-direction, a y-direction, and a z-direction. The first support bracket assembly has a first clamp that is configured to fix the first support bracket assembly relative to the structural member in the x-direction. The second support bracket assembly is configured to support a second end of the aerodynamic shield and to have a second position that is fixed relative to the structural member in the y-direction and the z-direction.

A flow control method is a flow control method of controlling flow around a blade of a rotary wing, a plasma actuator being disposed at the blade. The flow control method includes: determining a characteristic frequency ratio that is a characteristic value among frequency ratios, each of the frequency ratios being a ratio between an actuator driving frequency and an angle of attack changing frequency, the actuator driving frequency being a frequency of an applied voltage applied to the plasma actuator, the angle of attack changing frequency being a frequency at which an angle of attack of the blade changes in accordance with a rotation angle of the blade; setting the actuator driving frequency such that the frequency ratio becomes the characteristic frequency ratio; and applying a voltage of the set actuator driving frequency to the plasma actuator to control the flow around the blade.

Lifting devices are described that provide aeronautical lift by either pushing air sideways off its top surface, or by pulling away from top surface air, without changing upward air pressure on its bottom surface. In a first implementation, a pyramid shaped structure is composed of a stack of thin sections whose dimensions are rapidly extended and retracted using ultrasonic movements. Top surface air is pushed sideways when extended followed by momentary low pressure when retracted, thus providing lift. In a second implementation, a rapidly rotating lifting device is composed of a stack of thin round teethed plates, resembling circular saw blades, in which the diameter of each upper plate is slightly smaller than each lower plate. This device also creates lift as teeth push air sideways and gaps between teeth create momentary low pressure. In a third implementation, a lifting device top surface contains an array of MicroElectroMechanical Systems (MEMS) devices, such as Capacitive Micromachined Ultrasonic Transducers (CMUTs), which momentary produce lift by their upper pointing membranes rapidly pulling away from lifting device top surface air when oscillating at high frequency.

Systems and methods for enhancing operations of an aircraft may include a plasma generator, a sensor, and a controller. The plasma generator may be positioned on an exterior of the aircraft such that it can provide localized heating thereon. The sensor may be configured to sense and transmit information regarding a transonic flight condition such as speed to the controller. The controller may be configured to activate the plasma generator in response to information from the sensor, so as to mitigate a transonic shock wave through localized heating.

A free-streamline airfoil includes a front portion, the front portion including a leading edge geometry configured to force a sudden separation of the flow, and a contoured rear portion.

A free-streamline airfoil includes a front portion, the front portion including a leading edge geometry configured to force a sudden separation of the flow, and a contoured rear portion.

A wind-diverting apparatus for minimally shielding only the faster-moving drag-sensitive uppermost wheel surfaces from headwinds reduces overall vehicle drag. The apparatus includes various upper wheel fairings of FIGS. 1-6. Each fairing shields a primary vehicle-drag-inducing upper wheel surface from headwinds otherwise impinging directly thereon.

A wind-diverting apparatus for minimally shielding only the faster-moving drag-sensitive uppermost wheel surfaces from headwinds reduces overall vehicle drag. The apparatus includes various upper wheel fairings of FIGS. 1-6. Each fairing shields a primary vehicle-drag-inducing upper wheel surface from headwinds otherwise impinging directly thereon.