A Helmholtz resonator having a plurality of resonator chamber modules formed into an array. The array is configured to dampen sound. A module of the plurality of resonator chamber modules includes a first chamber and a second chamber. The first and second chambers have different lengths and are tuned to dampen different frequencies of sound.

A system and method for adaptively controlling a cooldown cycle of an auxiliary power unit (APU) that is operating and rotating at a rotational speed includes reducing the rotational speed of the APU to a predetermined cooldown speed magnitude that ensures combustor inlet temperature has reached a predetermined temperature value, determining, based on one or more of operational parameters of the APU, when a lean blowout of the APU is either imminent or has occurred, and when a lean blowout is imminent or has occurred, varying one or more parameters associated with the shutdown/cooldown cycle.

A system and method for adaptively controlling a cooldown cycle of an auxiliary power unit (APU) that is operating and rotating at a rotational speed includes reducing the rotational speed of the APU to a predetermined cooldown speed magnitude that ensures combustor inlet temperature has reached a predetermined temperature value, determining, based on one or more of operational parameters of the APU, when a lean blowout of the APU is either imminent or has occurred, and when a lean blowout is imminent or has occurred, varying one or more parameters associated with the shutdown/cooldown cycle.

A method for manufacturing a cellular core for an acoustic panel is provided. The cellular core includes at least one plurality of acoustic cells and a plurality of de-icing channels that extend longitudinally, each de-icing channel being transversely interposed between two successive cells, and the de-icing channels being adapted to channel a de-icing fluid. A manufacturing step includes producing the acoustic cells and the de-icing channels as a single piece such that the cellular core manufactured during the manufacturing step forms a monolithic part.

A method for manufacturing a cellular core for an acoustic panel is provided. The cellular core includes at least one plurality of acoustic cells and a plurality of de-icing channels that extend longitudinally, each de-icing channel being transversely interposed between two successive cells, and the de-icing channels being adapted to channel a de-icing fluid. A manufacturing step includes producing the acoustic cells and the de-icing channels as a single piece such that the cellular core manufactured during the manufacturing step forms a monolithic part.

An assembly is provided for a structure. This assembly includes a composite skin and a thermal anti-icing system. The composite skin extends between an exterior surface and an interior surface. The thermal anti-icing system includes a susceptor and a waveguide. The susceptor and the waveguide are integrated into the composite skin between the exterior surface and the interior surface. The waveguide is configured to direct microwaves to the susceptor for melting and/or preventing ice accumulation on the exterior surface.

An assembly is provided for a structure. This assembly includes a composite skin and a thermal anti-icing system. The composite skin extends between an exterior surface and an interior surface. The thermal anti-icing system includes a susceptor and a waveguide. The susceptor and the waveguide are integrated into the composite skin between the exterior surface and the interior surface. The waveguide is configured to direct microwaves to the susceptor for melting and/or preventing ice accumulation on the exterior surface.

The present invention discloses a supersonic inlet with synchronous adjustment of capture area and throat area, wherein the throat area may be adjusted by providing a movable throat section, while the capture area may be adjusted by providing a movable cowl section at the front end of the cowl lip, thereby realizing the effect that the capture area and the throat area of the inlet may be adjusted in synchronization. Meanwhile, the present invention also provides a control method and a design method of the above-mentioned inlet. The present invention greatly simplifies the actuation system and control system, significantly reduces the weight of the accessory system, and enables the performance of the inlet within a wide envelope range to be maintained in an excellent state.

An air inflow lip of a nacelle for a turbojet of an aircraft, including a cavity defined by a leading edge of the nacelle and by an annular wall, includes an inner wall, an acoustic treatment device, and a pneumatic de-icing device including a de-icing fluid supply device. The inner wall of the air inflow lip includes acoustic boreholes and the pneumatic de-icing device includes a honeycombed de-icing plate mounted inside the cavity on the inner wall of the air inflow lip. Also included are conduits for the circulation of a de-icing fluid and acoustic wells communicating with the acoustic boreholes.

An air intake including an air duct inside an aircraft, an inlet at one end of the air duct, a flap door and driving mechanism that moves the flap door between closed and open positions. The flap door includes a barrier filter configured to filter an incoming airflow into the air duct, and wherein the driving mechanism is configured to pivot the flap door about a first end of the door.