Abstract: A propulsion system and an aircraft that includes the propulsion system are provided. The propulsion system includes an engine and a cowling that surrounds at least a portion of the engine. The propulsion system also includes an inlet. The inlet includes a compression surface that is upstream and external to the cowling. The compression surface can slow air flow from a supersonic speed to a subsonic speed before the air flow enters the cowling.

Abstract: Embodiments of an inlet, aircraft, and propulsion system includes an inlet spike with a compression surface configured to decelerate air flow from supersonic speed to subsonic speed before the air flow enters a cowling throat and diffuser section of the propulsion system.

Abstract: A diverterless hypersonic inlet (DHI) for a high speed, air-breathing propulsion system reduces the ingested boundary layer flow, drag, and weight, and maintains a high capture area for hypersonic applications. The design enables high vehicle fineness ratios, low-observable features, and enhances ramjet operability limits. The DHI is optimized for a particular design flight Mach number. A forebody segment generates and focuses a system of multiple upstream shock waves at desired strengths and angles to facilitate required inlet and engine airflow conditions. The forebody contour diverts boundary layer flow to the inlet sides, effectively reducing the thickness of the boundary layer that is ingested by the inlet, while maintaining the capture area required by the hypersonic propulsion system. The cowl assembly is shaped to integrate with the forebody shock system and the thinned boundary layer region.

Abstract: A system, method, and apparatus for throat corner scoop offtake for mixed compression inlets for high speed aircraft engine applications is disclosed. The throat corner scoops are small air intakes located inside the large mixed compression inlet. They are positioned in a region otherwise prone to generate low pressure airflow. The throat corner scoops capture and remove the low pressure airflow from the bulk stream that is passed on to the engine. This location also provides inlet stability enhancement, and the airflow is used on the auxiliary systems.

Abstract: A system, method, and apparatus for throat corner scoop offtake for mixed compression inlets for high speed aircraft engine applications is disclosed. The throat corner scoops are small air intakes located inside the large mixed compression inlet. They are positioned in a region otherwise prone to generate low pressure airflow. The throat corner scoops capture and remove the low pressure airflow from the bulk stream that is passed on to the engine. This location also provides inlet stability enhancement, and the airflow is used on the auxiliary systems.

Abstract: A diverterless hypersonic inlet (DHI) for a high speed, air-breathing propulsion system reduces the ingested boundary layer flow, drag, and weight, and maintains a high capture area for hypersonic applications. The design enables high vehicle fineness ratios, low-observable features, and enhances ramjet operability limits. The DHI is optimized for a particular design flight Mach number. A forebody segment generates and focuses a system of multiple upstream shock waves at desired strengths and angles to facilitate required inlet and engine airflow conditions. The forebody contour diverts boundary layer flow to the inlet sides, effectively reducing the thickness of the boundary layer that is ingested by the inlet, while maintaining the capture area required by the hypersonic propulsion system. The cowl assembly is shaped to integrate with the forebody shock system and the thinned boundary layer region.

Abstract: A diverterless hypersonic inlet (DHI) for a high speed, air-breathing propulsion system reduces the ingested boundary layer flow, drag, and weight, and maintains a high capture area for hypersonic applications. The design enables high vehicle fineness ratios, low-observable features, and enhances ramjet operability limits. The DHI is optimized for a particular design flight Mach number. A forebody segment generates and focuses a system of multiple upstream shock waves at desired strengths and angles to facilitate required inlet and engine airflow conditions. The forebody contour diverts boundary layer flow to the inlet sides, effectively reducing the thickness of the boundary layer that is ingested by the inlet, while maintaining the capture area required by the hypersonic propulsion system. The cowl assembly is shaped to integrate with the forebody shock system and the thinned boundary layer region.

Abstract: An advanced aperture inlet (AAI) uses a three-dimensional, mixed compression inlet design derived from computational fluid dynamics (CFD) by streamline tracing a supersonic section from an axisymmetric mixed compression inlet solution. The axisymmetric design is used to obtain a CFD solution with slip wall boundaries at the inlet design point and serves as a flow field generator for the AAI. The AAI geometry is obtained by projecting a desired aperture shape onto a surface model of the external oblique shock. Streamline seeds are located on the projected aperture segments and transferred into the CFD solution space. The streamlines generated by these seeds inside the CFD solution space are then used as a wireframe to define the supersonic diffuser back to the throat location. Traditional design techniques are then used to define the subsonic diffuser from the inlet throat to the engine face.