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 inlet arrangement is disclosed herein for use with a supersonic jet engine configured to consume air at a predetermined mass flow rate when the supersonic jet engine is operating at a predetermined power setting and moving at a predetermined Mach speed. The air inlet arrangement includes, but is not limited to, a cowl having a cowl lip and a center body coaxially aligned with the cowl. A protruding portion of the center body extends upstream of the cowl lip for a length greater than a conventional spike length. The protruding portion is configured to divert air flowing over the protruding portion out of a pathway of an inlet to the supersonic jet engine such that a remaining airflow approaching and entering the inlet matches the predetermined mass flow rate.

An inlet arrangement is disclosed herein for use with a supersonic jet engine configured to consume air at a predetermined mass flow rate when the supersonic jet engine is operating at a predetermined power setting and moving at a predetermined Mach speed. The air inlet arrangement includes, but is not limited to, a cowl having a cowl lip and a center body coaxially aligned with the cowl. A protruding portion of the center body extends upstream of the cowl lip for a length greater than a conventional spike length. The protruding portion is configured to divert air flowing over the protruding portion out of a pathway of an inlet to the supersonic jet engine such that a remaining airflow approaching and entering the inlet matches the predetermined mass flow rate.

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 exemplary engine noise reduction system, can be provided, which can include a noise reduction fluid source, and a microjet(s) placed at an axial location downstream from a nozzle exit of an engine and configured to asymmetrically inject a noise reduction fluid from the noise reduction fluid source into a jet flow of the engine. The engine can be a jet engine. The microjet(s) can include four microjets, which can be about 90 degrees apart in a plane at the axial location. The four microjets can be asymmetric microjets. The microjet(s) can be configured to inject the noise reduction fluid in a direction that is normal with respect to the jet flow.

An exemplary engine noise reduction system, can be provided, which can include a noise reduction fluid source, and a microjet(s) placed at an axial location downstream from a nozzle exit of an engine and configured to asymmetrically inject a noise reduction fluid from the noise reduction fluid source into a jet flow of the engine. The engine can be a jet engine. The microjet(s) can include four microjets, which can be about 90 degrees apart in a plane at the axial location. The four microjets can be asymmetric microjets. The microjet(s) can be configured to inject the noise reduction fluid in a direction that is normal with respect to the jet flow.

Disclosed are laminates comprising a carbon fiber reinforced polymer sheet and a layer of polysilazane and methods for producing such laminates.

An exhaust muffler for an APU of an aircraft, including an exhaust gases inlet, an exhaust gases outlet, a peripheral wall configured to guide a flow of exhaust gases between the inlet and the outlet. The peripheral wall includes at least one vacuum chamber to provide thermal insulation.

A mixer is mounted in an aircraft. A rear end part of a cylindrical portion of the mixer is divided by a guide vane into a plurality of divided tubular portions. In the plurality of divided tubular portions, a notch nozzle is formed on an outer wall of the cylindrical portion. A plurality of guide holes are formed to extend from the outer wall of the cylindrical portion to a rear end surface of the guide vane.