An assembly is provided for an aircraft propulsion system. This assembly includes a first acoustic panel and a second acoustic panel. The first acoustic panel includes a first perforated skin, a first non-perforated skin and a first cellular core arranged between and connected to the first perforated skin and the first non-perforated skin. The first perforated skin is configured with a plurality of first perforations. A first of the first perforations has a first width. A second acoustic panel includes a second perforated skin, a second non-perforated skin and a second cellular core arranged between and connected to the second perforated skin and the second non-perforated skin. The second perforated skin is configured with a plurality of second perforations. A first of the second perforations has a second width that is smaller than the first width.

A fan blade assembly having integrated microphones to measure acoustic energy levels uses speakers controlled by a control unit to output anti-acoustic energy vibrations. Specific embodiments wherein the speakers and microphones are radially displaced around the fan blade assembly are also disclosed.

An arrowhead aircraft includes a pair of counter-rotating propellers, a jet engine module, and an exhausted module, wherein the counter-rotating propellers propel the aircraft but does not have angular momentum, and the exhausted module deployed around the exhausted end of the jet engine module, which reuses the waste heat from the exhausted end and reduces the noise. Wherein, the airflow system includes a shutter deployed at the bottom side of the body that controls the streamlines of airflow through the aircraft and a plurality of airfoils that will force the aircraft tilted to the desired direction. The present invention resolved the helicopter's vulnerabilities, such as its intricate mechanism, dragging response, dangers blades, hard to control angular momentum, high cost, and high training level.

An extremely quiet short take-off and landing (STOL) aircraft includes: two wings, wherein each wing comprises an engine system; a fuselage structurally connected to each wing; and a ducted fan thruster positioned on the fuselage in an orientation that is rotated relative to the typical orientation on a helicopter. An extremely quiet STOL aircraft includes: two wings, wherein each wing comprises an engine system; a fuselage structurally connected to each wing; channel shrouds surrounding at least one of the engine systems; and a ducted fan thruster positioned on the fuselage. An extremely quiet STOL aircraft includes: two wings, wherein each wing comprises an engine system, the engine system comprising two engine dual packs; a fuselage structurally connected to each wing; and a ducted fan thruster positioned on the fuselage.

The present disclosure concerns an acoustic attenuation panel for an aircraft turbojet engine nacelle and a method for manufacturing this panel. The acoustic attenuation panel includes an alveolar central core interposed between an acoustic front skin comprising perforations and a rear skin, the acoustic attenuation panel including a front structure and a rear structure. The front structure includes the acoustic front skin and a first network of alveolar walls, the rear structure including the rear skin and a second network of alveolar walls, the first and second networks of alveolar walls being complementary so as to form, in an assembled position, the alveolar central core, the front structure and the rear structure being positioned opposite to each other and so that the network of alveolar walls of a structure is spaced from the skin of the other structure facing it by a clearance d.

A ducted fan housing for directing a duct flow includes an annular cowling and an adjustable fan duct nozzle. The nozzle includes a flexible sleeve having rigid areas arranged circumferentially around the nozzle orifice and connected by flexible areas so as to form a unitary sleeve structure. The rigid areas are radially moveable between a normal configuration in which the orifice is smaller and a dilated configuration in which the orifice is larger. A drive mechanism uses drive elements to move at least some of the rigid areas between the configurations to adjust the size of the orifice. The rigid areas may be constructed from laminated graphite and epoxy, and the flexible areas may be constructed from laminated graphite and soft resin. If the housing includes a thrust reverser, then a flexible joint area extends circumferentially around the housing and connects the flexible sleeve to a thrust reverser cowl.

A ducted fan housing for directing a duct flow includes an annular cowling and an adjustable fan duct nozzle. The nozzle includes a flexible sleeve having rigid areas arranged circumferentially around the nozzle orifice and connected by flexible areas so as to form a unitary sleeve structure. The rigid areas are radially moveable between a normal configuration in which the orifice is smaller and a dilated configuration in which the orifice is larger. A drive mechanism uses drive elements to move at least some of the rigid areas between the configurations to adjust the size of the orifice. The rigid areas may be constructed from laminated graphite and epoxy, and the flexible areas may be constructed from laminated graphite and soft resin. If the housing includes a thrust reverser, then a flexible joint area extends circumferentially around the housing and connects the flexible sleeve to a thrust reverser cowl.

An aircraft control system and method to optimize aircraft control based on noise abatement volumes. A noise abatement component computes optimal flight and engine control based on a line-of-sight distance to minimize direct operating cost (DOC) while complying with community noise regulations.

An acoustic attenuation panel for a propulsion unit including a nacelle and a turbojet engine includes a cellular core disposed between an inner skin and an outer skin, called acoustic skin, the acoustic skin including a plurality of acoustic apertures, the acoustic apertures being inclined, at a non-zero inclination angle (β) relative to the direction normal to the acoustic skin, upstream with respect to the flow direction of the air or gas flow to which the panel is intended to be subjected under normal operating conditions, that is to say upstream of the propulsion unit when the panel is mounted in such a unit.

A thermal management system includes a heat exchanger and a housing that receives the heat exchanger. The heat exchanger defines a heat transfer region within which thermal exchange occurs between a process fluid and a thermal management fluid. The thermal management system further includes a process fluid conduit to convey the process fluid through the heat transfer region and an actuator assembly configured to position the heat exchanger relative to the housing. The actuator assembly is configured to selectively assume a position between a stowed position and a deployed position. When the actuator assembly is in the deployed position, the heat transfer region extends within a flow of the thermal management fluid such that the process fluid flow flows in heat exchange relation with the thermal management fluid flow. In some such embodiments, the actuator assembly automatically transitions between the stowed position and the deployed position.