Technologies for providing noise shielding are described herein. In some examples, noise shields are installed proximate to one or more of the main engines of the aircraft. The noise shields can be extended during terminal operations and retracted during flight operations.

Technologies for providing noise shielding are described herein. In some examples, noise shields are installed proximate to one or more of the main engines of the aircraft. The noise shields can be extended during terminal operations and retracted during flight operations.

A ducted fan assembly includes a duct having an inlet, an inner surface, an expanding diffuser and an outlet. A fan disposed within the duct between the inlet and the expanding diffuser is configured to rotate about a fan axis to generate airflow. An active flow control system includes a plurality of injection zones circumferentially distributed about the inner surface. The expanding diffuser has a diffuser angle configured to create flow separation when the airflow is uninfluenced by the active flow control system such that the airflow has a thrust vector with a first direction that is substantially parallel to the fan axis. Injection of pressurized air from one of the injection zones asymmetrically reduces the flow separation between the airflow and the expanding diffuser downstream of that injection zone such that the thrust vector of the airflow has a second direction that is not parallel to the first direction.

A ducted fan assembly includes a duct having an inlet, an inner surface, an expanding diffuser and an outlet. A fan disposed within the duct between the inlet and the expanding diffuser is configured to rotate about a fan axis to generate airflow. An active flow control system includes a plurality of injection zones circumferentially distributed about the inner surface. The expanding diffuser has a diffuser angle configured to create flow separation when the airflow is uninfluenced by the active flow control system such that the airflow has a thrust vector with a first direction that is substantially parallel to the fan axis. Injection of pressurized air from one of the injection zones asymmetrically reduces the flow separation between the airflow and the expanding diffuser downstream of that injection zone such that the thrust vector of the airflow has a second direction that is not parallel to the first direction.

A propulsor includes a propulsor body and a prop assembly in rotational communication with the propulsor body. The prop assembly includes a plurality of prop blades configured for rotation about an axial centerline of the propulsor. The plurality of prop blades are rotatable between a deployed position and a stowed position. The propulsor further includes at least one linkage having a first linkage end and a second linkage end. The first linkage end of the at least one linkage is rotatably mounted to the propulsor body and the second linkage end is configured to be rotatably mounted to an aircraft body. The propulsor further includes a first motor coupled to the at least one linkage and configured to rotate the at least one linkage relative to the propulsor body between a first rotational position and a second rotational position.

A propulsor includes a propulsor body and a prop assembly in rotational communication with the propulsor body. The prop assembly includes a plurality of prop blades configured for rotation about an axial centerline of the propulsor. The plurality of prop blades are rotatable between a deployed position and a stowed position. The propulsor further includes at least one linkage having a first linkage end and a second linkage end. The first linkage end of the at least one linkage is rotatably mounted to the propulsor body and the second linkage end is configured to be rotatably mounted to an aircraft body. The propulsor further includes a first motor coupled to the at least one linkage and configured to rotate the at least one linkage relative to the propulsor body between a first rotational position and a second rotational position.

An unmanned aerial vehicle (UAV) for gas transport is disclosed. The UAV includes a fuselage enclosing a volume, and a gas reservoir enclosed within the fuselage, filling at least a majority of the volume. The gas reservoir is configured to receive and store a gas at a pressure no greater than 100 bar. The UAV also includes a propulsion system having at least one engine, each of the at least one engine coupled to a prop that is driven by the at least one engine using energy derived from the gas stored in the gas reservoir. The UAV also includes a control system communicatively coupled to the propulsion system and configured to operate the unmanned aerial vehicle to autonomously transport the gas. The UAV may have a footprint while on the ground, and the footprint of the UAV may be no larger than three standard parking spaces.

A blended wing body aircraft having an interior cabin with a usable volume of at most 4500 ft.sup.3 and a cabin aspect ratio of at most 4, wherein a combination of the wings and center body has a wetted aspect ratio of at least 1.7 and at most 2.8. Also, a blended wing body aircraft having an interior cabin with a usable volume of at least 1500 ft.sup.3 and at most 4500 ft.sup.3 and a cabin aspect ratio of at least 2 and at most 4, wherein a combination of the wings and center body has a wetted aspect ratio of at least 1.9 and at most 2.7. Also, a blended wing body aircraft wherein at least each profile section having normalized half-span values from 0 to 0.3 has a leading edge having a normalized height having a nominal value within the range set forth in Table 4.

A blended wing body aircraft having an interior cabin with a usable volume of at most 4500 ft.sup.3 and a cabin aspect ratio of at most 4, wherein a combination of the wings and center body has a wetted aspect ratio of at least 1.7 and at most 2.8. Also, a blended wing body aircraft having an interior cabin with a usable volume of at least 1500 ft.sup.3 and at most 4500 ft.sup.3 and a cabin aspect ratio of at least 2 and at most 4, wherein a combination of the wings and center body has a wetted aspect ratio of at least 1.9 and at most 2.7. Also, a blended wing body aircraft wherein at least each profile section having normalized half-span values from 0 to 0.3 has a leading edge having a normalized height having a nominal value within the range set forth in Table 4.

A propeller includes a hub coaxially surrounding a longitudinal axis. A ring shroud coaxially surrounds the longitudinal axis and is spaced radially from the hub. At least one propeller blade is fixedly attached to both the hub and ring shroud and extends radially therebetween for mutual rotation therewith. At least one stub blade has a first stub end radially spaced from a second stub end. The first stub end is fixedly attached to a selected one of the hub and ring shroud. The second stub end is cantilevered from the first stub end and is radially interposed between the first stub end and the selected one of the hub and ring shroud.