Provided are a flap drive device and a rotorcraft blade, and more particularly, a flap drive device using a two-section link mechanism, which may be applied to a rotorcraft blade, and a rotorcraft blade including the same.

A self-latching piezocomposite actuator includes a plurality of shape memory ceramic fibers. The actuator can be latched by applying an electrical field to the shape memory ceramic fibers. The actuator remains in a latched state/shape after the electrical field is no longer present. A reverse polarity electric field may be applied to reset the actuator to its unlatched state/shape. Applied electric fields may be utilized to provide a plurality of latch states between the latched and unlatched states of the actuator. The self-latching piezocomposite actuator can be used for active/adaptive airfoils having variable camber, trim tabs, active/deformable engine inlets, adaptive or adjustable vortex generators, active optical components such as mirrors that change shapes, and other morphing structures.

Provided are a flap drive device and a rotorcraft blade, and more particularly, a flap drive device using a two-section link mechanism, which may be applied to a rotorcraft blade, and a rotorcraft blade including the same.

A system and method of increasing the control authority of redundant stability and control augmentation system (SCAS) actuators by utilizing feedback between systems such that one system may compensate for the position of a failed actuator of the other system. Each system uses an appropriate combination of reliable and unreliable inputs such that unreliable inputs cannot inappropriately utilize the increased authority. Each system may reconfigure itself when the other system actuator fails at certain positions so that the pilot or other upstream input maintains sufficient control authority of the aircraft.

A system and method of increasing the control authority of redundant stability and control augmentation system (SCAS) actuators by utilizing feedback between systems such that one system may compensate for the position of a failed actuator of the other system. Each system uses an appropriate combination of reliable and unreliable inputs such that unreliable inputs cannot inappropriately utilize the increased authority. Each system may reconfigure itself when the other system actuator fails at certain positions so that the pilot or other upstream input maintains sufficient control authority of the aircraft.

An aerofoil has a main portion of aerofoil cross section and a trailing edge portion (12) movable with respect to the main portion by an actuating device (14), the trailing edge portion (12) is movable at or about an area/point of flexion A, the area/point of flexion A is located at or adjacent a pressure or suction surface of the aerofoil, the trailing edge portion (12) is connected to the main portion by first and second connection members (18, 20), the first connection member (18) extends inwardly away from the area/point of flexion A and has an end which is directly or indirectly connected to the main portion, the first and second connection members (18, 20) are flexible.

Features for a tail-sitter aircraft having efficiently designed propulsive elements are disclosed. The aircraft may have a tail with landing mounts to support the aircraft in a vertical position for takeoff and landing. The aircraft may have a hybrid propulsion system including an electric power source, such as a generator and an electric motor, and a prime power subsystem, such as an internal combustion engine. The electric and prime power subsystems may be used controllably in varying amounts depending on the phase of flight, such as takeoff, horizontal flight, landing, or maneuvers. The aircraft may have blades with piezo elements to provide shape-changing capability to the blade. The shape of the blade, such as the pitch and/or twist, may be controllably changed for optimal efficiency with the blade depending on phase of flight. The blade shape may be changed from a rotor-like shape during takeoff and landing, to a propeller-like shape during horizontal flight.

A system and method of increasing the control authority of redundant stability and control augmentation system (SCAS) actuators by utilizing feedback between systems such that one system may compensate for the position of a failed actuator of the other system. Each system uses an appropriate combination of reliable and unreliable inputs such that unreliable inputs cannot inappropriately utilize the increased authority. Each system may reconfigure itself when the other system actuator fails at certain positions so that the pilot or other upstream input maintains sufficient control authority of the aircraft.

A system and method of increasing the control authority of redundant stability and control augmentation system (SCAS) actuators by utilizing feedback between systems such that one system may compensate for the position of a failed actuator of the other system. Each system uses an appropriate combination of reliable and unreliable inputs such that unreliable inputs cannot inappropriately utilize the increased authority. Each system may reconfigure itself when the other system actuator fails at certain positions so that the pilot or other upstream input maintains sufficient control authority of the aircraft.

A method of increasing the control authority of redundant stability and control augmentation system (SCAS) actuators by utilizing feedback between systems such that one system may compensate for the position of a failed actuator of the other system. Each system uses an appropriate combination of reliable and unreliable inputs such that unreliable inputs cannot inappropriately utilize the increased authority. Each system may reconfigure itself when the other system actuator fails at certain positions so that the pilot or other upstream input maintains sufficient control authority of the aircraft.