Sounds are generated by an aerial vehicle during operation. For example, the motors and propellers of an aerial vehicle generate sounds during operation. Disclosed are systems, methods, and apparatus for actively adjusting the position and/or configuration of one or more propeller blades of a propulsion mechanism to generate different sounds and/or lifting forces from the propulsion mechanism.

Noise-abatement systems provide noise abatement to a wing assembly provided with a forward edge slat and include an elongate shield element which is unconnected but positionable adjacent to a lower trailing edge of the edge slat along a lengthwise extent thereof, and a support web having a distal end fixed to the shield element and a proximal end capable of fixation to an interior cove surface of the edge slat adjacent an upper trailing edge thereof. The support web will therefore allow movement of the shield element towards and away from the lower trailing edge of the edge slat between an operative position wherein the shield element is positioned adjacent to the lower trailing edge of the edge slat along the lengthwise extent thereof and an inoperative position wherein the edge slat is spaced from the trailing edge of the edge slat and positioned in the cove region thereof, respectively.

A movable aerodynamic surface for an aircraft is disclosed including a skin having a first skin portion and a second skin portion both extending from the leading edge to the trailing edge and together surrounding an interior from opposite sides, and a stiffener arrangement arranged in the interior and including at least an inboard stiffener in the area of the inboard end and/or an outboard stiffener in the area of the outboard end. At the inboard end between the first skin portion, the second skin portion and the inboard stiffener an inboard cavity is formed, and/or at the outboard end between the first skin portion, the second skin portion and the outboard stiffener an outboard cavity is formed. An acoustic filler arrangement including multiple filler elements is arranged within the inboard cavity and/or the outboard cavity for reducing noise.

An apparatus configured to reduce acoustic interactions between a propeller and a surface of an aircraft positioned downstream of the propeller includes a surface modification element of the surface of the aircraft. The surface modification element defines a modified contour of the surface. The modified contour is configured to decorrelate a phase distribution of a plurality of sound sources within a source field positioned on at least a portion of the surface.

Sounds are generated by an aerial vehicle during operation. For example, the motors and propellers of an aerial vehicle generate sounds during operation. Disclosed are systems, methods, and apparatus for actively adjusting the position and/or configuration of one or more propeller blades of a propulsion mechanism to generate different sounds and/or lifting forces from the propulsion mechanism.

Sounds are generated by an aerial vehicle during operation. For example, the motors and propellers of an aerial vehicle generate sounds during operation. Disclosed are systems, methods, and apparatus for actively adjusting the position and/or configuration of one or more propeller blades of a propulsion mechanism to generate different sounds and/or lifting forces from the propulsion mechanism.

A structure ensuring acoustic attenuation of a flow of a first fluid and heat exchange between a first fluid and a second fluid. The structure includes a first wall which is perforated, a second wall, and a plurality of intermediate walls extending between the first wall and the second wall. For each intermediate wall, there is a pipe intended to receive the second fluid and inscribed within the intermediate wall. Such a structure makes it possible to optimally integrate the acoustic wave attenuation function and the heat exchange function.

The invention relates to a profiled structure, elongated in a direction in which the structure has a length exposed to an airflow, and transversely to which the structure has a leading edge (164) and/or a trailing edge, at least one of which is profiled and has, in said direction of elongation, serrations (28a) defined by successive teeth (30) and depressions (32).

Along the profiled leading edge and/or profiled trailing edge, the successive teeth (30) and depressions (32) extend only over a part of said length exposed to the flow over which the amplitude and/or spacing of the teeth varies monotonically except for the few teeth nearest each end of said part, a remaining part (280) of said length being smooth.

Systems and methods for noise suppression for aircraft are disclosed. The aircraft may include a fuselage. The aircraft may include a plurality of wings connected to or formed with the fuselage. The aircraft may include at least one engine configured to generate a propulsion force to propel the aircraft. The at least one engine may include a nozzle assembly having a nozzle body with an outlet that releases an exhaust air or a jet flow. The aircraft may include a noise suppression assembly. The noise suppression assembly may be configured to interact with the exhaust air or jet flow to substantially suppress, mitigate, reduce, or otherwise modify noise generated by the aircraft.

An end rib assembly for a high-lift device of an aircraft to reduce the noise caused by the transition between the wing and a high-lift device as well as the noise caused by the lateral side edge of the end rib assembly. An end rib assembly includes a noise-reducing portion configured to reduce noise caused by an airflow around the end rib assembly, and a guiding portion configured for guiding the end rib assembly along a pre-determined path when the high-lift device is moved between a retracted position and an extended position, wherein the guiding portion is formed such that an airflow impinging on the guiding portion is partly guided towards the noise-reducing portion.