Embodiments are directed to systems and methods for determining an optimal engine inlet area to minimize spillage drag. An algorithm may utilize aircraft parameters, aircraft performance charts, and engine models to determine the engine inlet area as a function of engine air mass flow, airspeed, and air density at current ambient conditions.

An inlet barrier filter system for a tiltrotor aircraft comprising a filter duct extending from a filter to a filter outlet, a ram air duct extending from a ram air inlet to an engine where the filter duct connects to the ram air duct at the filter outlet, and a closure member movable between a first position blocking the ram air duct and a second position blocking the filter outlet. In use, the inlet barrier filter system provides for two mutually exclusive air flow paths, one for introducing ram air to the engine while closing off the filter and another air flow path for introducing filtered air to the engine while closing off the ram air duct.

A system that filters airborne particles when the aircraft is in a dusty environment and is disengaged when the aircraft is flying up and away from the dusty environment.

An aircraft having a blended-wing-body configuration includes a centerbody, a pair of wings, at least one pair of engines, a pair of air inlets, and a pair of exhaust outlets. The centerbody has an airfoil-shaped cross section, an aircraft centerline, an aft portion, an upper mold line, a lower mold line, and a pair of centerbody leading edge portions respectively on opposite sides of the aircraft centerline. The wings are integral with the centerbody. The pair of engines are located on opposite sides of the aircraft centerline and are mounted within the centerbody between the upper mold line and the lower mold line. The pair of air inlets are located respectively along the centerbody leading edge portions and are respectively fluidly coupled to the pair of engines. The pair of exhaust outlets our located in the aft portion of the centerbody and our respectively fluidly coupled to the pair of engines.

This disclosure relates to an air inlet for an aircraft with an integrated hand hold. One innovative aspect of the subject matter described herein can be implemented as an air inlet on the exterior surface of a cowling for a rotorcraft, wherein the air inlet having a scoop that includes a bottom surface having a wide, flat, front edge that angles downward towards the back, an opening in the back for air to enter, and two lateral sides coupled to the bottom surface, where the two sides are planar on a top surface and become longer in height towards the opening in the back, and hand hold, where the hand hold is a trough or an indentation in the bottom surface of the scoop that extends along a side.

A system and method of an airflow control system for a vehicle is described herein. The airflow control system (100) includes an airflow housing (120) defining an airflow passageway (125) extending between a bypass opening (122) and an intake outlet (124). The airflow housing also defines a duct opening (126) positioned between the bypass opening (122) and the intake outlet (124). The intake outlet (124) may be in fluid communication with an engine intake (12) of the vehicle such that air passes from the bypass opening (122) and/or the duct opening (126) to the engine intake (12). The airflow control system (100) also includes a movable duct (160) movably connected to the airflow housing (120) to selectively allow or prevent air passage through the duct opening (126) and into the engine intake (12), and further includes a bypass door (140) movably connected to the airflow housing (120) to selectively allow or prevent air passage through the bypass opening (122) and into the engine intake (12).

One embodiment is an inlet plenum assembly for a rotary aircraft that includes an inlet plenum defined on a first side by an inlet plenum wall and on a second side by a forward firewall assembly, the forward firewall assembly having an inlet aperture configured to receive a drive shaft to rotatably coupled to an engine; and a seal connected to the forward firewall assembly via a seal retainer disposed around a periphery of the inlet aperture. The forward firewall assembly may further include a forward firewall upper portion and a forward firewall lower portion, the forward firewall upper portion configured to removably seat to the forward firewall lower portion. The seal retainer may be attached to the forward firewall assembly via a plurality of bolts disposed around the periphery of the seal retainer. In some embodiments, the seal is connected to an inlet duct of the engine.

An air intake unit for an engine of a vehicle includes a housing, a bypass air intake, a shutter element, and actuator. A plenum is defined inside the housing which can be connected to the engine. Air coming from the outside needed for the operation of the engine can be sucked into the plenum through the bypass air intake. The shutter element is coupled to the bypass air intake and is mounted to move between a closed position, in which the shutter element closes the bypass air intake, and an open position, in which the shutter element leaves the passage through the bypass air intake free. The actuator is configured to move the shutter element between the closed position and the open position. The actuator has a spring configured to generate, by expanding, an opening movement moving the shutter element from the closed position to the open position.

An aircraft includes a fuselage, an engine exhaust port extending through the fuselage, an air intake extending through the fuselage forward from, and adjacent to, the engine exhaust port, and an air cleaning assembly positioned over the air intake. The aircraft also includes a pressure recovery device including an outer wall positioned above the air cleaning assembly. A distance from a forward edge of the outer wall to the air cleaning assembly is greater than a distance from an aft edge of the outer wall to the air cleaning assembly. An inlet flow axis is defined normal to a cross-sectional flow area of the pressure recovery device at the forward edge, and is oriented upward at an acute angle relative to a longitudinal axis of the aircraft.

A boundary layer utilization apparatus for intake of air to a high speed aircraft, comprises a first air inlet adjacent an exterior surface of a fuselage of the aircraft and offset from the fuselage enough to integrate a second air inlet in the offset space to ingest and divert the boundary layer air flowing next to the fuselage into the aircraft for a useful purpose such as cooling the engine compartment. The second air inlet is disposed aft of the first air inlet to minimize hot gas re-ingestion.