A variable pitch bladed disc including a plurality of blades, each being of variable pitch about a blade axis of rotation and having a root, the plurality of blades including at least one first blade and at least one second blade, a plurality of rotor connecting shafts, each shaft having a root and a tip, the root of each blade being mounted on the tip of a corresponding rotor connecting shaft via a pivot so as to allow each blade to be rotated about the blade axis of rotation, the first blade having a first rotation axis inclination such that the rotation axis thereof is inclined in a fixed manner with respect to a radial axis passing through the root of the corresponding shaft, and the second blade has a second rotation axis inclination different from the first rotation axis inclination.

The presently disclosed embodiments relate to vertical takeoff and landing (VTOL) aircraft that have the capability of hovering in both a “nose forward” and a “nose up” orientation, and any orientation between those two. The disclosed aircraft can also transition into wing born (non-hovering) flight from any of the hovering orientations. In addition, certain of the disclosed embodiments can, if desired, use only vectored thrust control to maintain stable flight in both hover and forward flight. No control surfaces (e.g. ailerons, elevators, rudders, flaps) are required to maintain a stable vehicle attitude. However, the disclosure contemplates aircraft both with and without such control surfaces.

An active flow control system for generating pitch control moments for an aircraft during flight. The system includes a nozzle disposed proximate the aft end of the aircraft. The nozzle is configured to discharge a gas stream in the aftward direction. A pressurized air system includes a pressurized air source and one or more injectors configured to selectively inject pressurized air into the nozzle to influence the path of the gas stream. Based upon which injectors are injecting pressurized air into the nozzle, the gas stream exits the nozzle generating no pitch control moment, generating a pitch down control moment or generating a pitch up control moment.

An aircraft and a control method therefor, wherein a prescribed range in a P1 direction and a P2 direction that are centered on a neutral position is set as a neutral area for a grip handle. In accordance with the position or amount of operation of the grip handle, a flight controller makes the aircraft advance or reverse. When the grip handle as operated in the P1 direction or the P2 direction has moved into the neutral area, the flight controller makes the aircraft decelerate.

An aircraft and a control method therefor. The aircraft has: a velocity acquisition unit that acquires the velocity of the aircraft; a roll angle calculation unit that calculates the roll angle of the aircraft; a turning radius calculation unit that calculates the turning radius of the aircraft on the basis of the velocity and the roll angle; and a yaw rate calculation unit that calculates the yaw rate of the aircraft on the basis of the velocity and the turning radius. A control unit controls flight of the aircraft on the basis of the roll angle and the yaw rate.

An aircraft operable to transition between thrust-borne lift in a VTOL orientation and wing-borne lift in a forward flight orientation. The aircraft has a blended wing body and includes an engine, a unitary lift fan system, a forced air bypass system and an exhaust system. The engine has a turboshaft mode and a turbofan mode. The lift fan system includes a ducted fan. In the VTOL orientation of the aircraft, the engine is in the turboshaft mode coupled to the lift fan system such that the engine provides rotational energy to the ducted fan generating the thrust-borne lift. In the forward flight orientation of the aircraft, the engine is in the turbofan mode coupled to the forced air bypass system such that the bypass air combines with the engine exhaust in the exhaust system to provide forward thrust generating the wing-borne lift.

An aircraft operable to transition between thrust-borne lift in a VTOL orientation and wing-borne lift in a forward flight orientation. The aircraft has a blended wing body and includes an engine, a unitary lift fan system, a forced air bypass system and an exhaust system. The engine has a turboshaft mode and a turbofan mode. The lift fan system includes a ducted fan. In the VTOL orientation of the aircraft, the engine is in the turboshaft mode coupled to the lift fan system such that the engine provides rotational energy to the ducted fan generating the thrust-borne lift. In the forward flight orientation of the aircraft, the engine is in the turbofan mode coupled to the forced air bypass system such that the bypass air combines with the engine exhaust in the exhaust system to provide forward thrust generating the wing-borne lift.

An active flow control system for generating yaw control moments for an aircraft during forward flight. The system includes right and left yaw effectors disposed proximate the right and left wingtips of the wing. A pressurized air system includes a pressurized air source and a plurality of injectors operably associated with the right and left yaw effectors that influence the path of airflow above and below the yaw effectors. Based upon which of the injectors is injecting pressurized air, the right and left yaw effectors generate no yaw control moment, generate a yaw right control moment or generate a yaw left control moment.

Propeller assemblies, aircraft including the same, and associated methods. A propeller assembly includes a first propeller and a second propeller operatively coupled to a coupling shaft and configured to pivot with respect to one another about a propeller rotation axis. The propeller assembly additionally includes a coupling assembly operatively coupled to the first propeller and the second propeller and configured to transition between a plurality of pivotal configurations defined between and including a stowed configuration and a deployed configuration. The coupling assembly transitions from the stowed configuration toward the deployed configuration when a coupling assembly rotational velocity rises above a threshold stowed rotational velocity. In examples, an aircraft includes one or more propeller assemblies operatively coupled to a fuselage. In some examples, a method of operating a propeller assembly includes automatically transitioning a coupling assembly of the propeller assembly between a stowed configuration and a deployed configuration.

An aircraft operable to transition between thrust-borne lift in a VTOL orientation and wing-borne lift in a forward flight orientation. The aircraft has a blended wing body and includes an engine, a binary lift fan system, a forced air bypass system and an exhaust system. The engine has a turboshaft mode and a turbofan mode. The lift fan system includes a plurality of ducted fans in a tandem lateral orientation. In the VTOL orientation of the aircraft, the engine is in the turboshaft mode coupled to the lift fan system such that the engine provides rotational energy to the ducted fans generating the thrust-borne lift. In the forward flight orientation of the aircraft, the engine is in the turbofan mode coupled to the forced air bypass system such that the bypass air combines with the engine exhaust in the exhaust system to provide forward thrust generating the wing-borne lift.