Systems and methods include providing a helicopter, with a fuselage, a tail boom extending from the fuselage, a main rotor system, and a tail rotor assembly disposed on an aft end of the tail boom. The tail rotor assembly includes a tail rotor housing, at least one normal ducted fan that generate anti-torque thrust to prevent rotation of the fuselage, and at least one canted ducted fan configured to generate both anti-torque thrust to prevent of the fuselage and lift to the tail boom in order to control the pitch of the helicopter. The canted ducted fans generate sufficient lift to prevent a nose-up orientation of the helicopter when the center of gravity of the helicopter is shifted rearward behind the main rotor system, while the normal ducted fans maintain sufficient anti-torque thrust to prevent rotation of the fuselage when the main rotor is operated.

In one aspect, there is provided an aircraft, including a fuselage having a longitudinal axis extending from a front portion through an aft portion; first and second tail members extending from the aft portion; a first cross-flow fan system rotatably mounted to the first tail member; and a second cross-flow fan system rotatably mounted to the second tail member. The first and second cross-flow fan systems are configured to provide a forward thrust vector and an anti-torque vector on the aircraft. The first and second cross-flow fan systems can have a rotational axis oriented generally vertically. In another aspect, there is an aircraft including a fuselage having a front portion and a tail portion; and a cross-flow fan system supported by the tail portion. Embodiments include a cross-flow fan system retrofittable onto an aircraft and methods for retrofitting an aircraft with a cross-flow fan system.

A propulsion system comprising independent rotor sub-systems producing a thrust force of a desired magnitude in any desired radial direction from the center of the propulsion system, driven from a single driveshaft that may be fixed in its position in the vehicle. When the propulsion system is fitted, for example, to a single-main-rotor helicopter in place of the convention anti-torque tail rotor, the helicopter is thereby equipped with a propulsion system that can produce yaw, pitch, the anti-torque lateral thrust for stability in hover, aft thrust or drag as well as the direct forward thrust that will enable the helicopter to fly at higher speeds. The propulsion system may also be applied in other aeronautical systems as well as to marine and industrial systems to impart energy into a fluid and thereby induce movement in that fluid.

An aircraft assembly is provided and includes a first member extending from an aircraft airframe, a propeller, which is drivable to rotate and a secondary member on which the propeller is supportable and which is aerodynamically pivotable with respect to the first member.

An anti-torque rotor is described comprising: a mast rotatable about a first axis; a plurality of blades hinged on the mast and rotatable about respective second axes to vary the respective angles of attack; a control element sliding along the first axis with respect to the mast, rotatable with the mast and connected to the blades to cause the rotation about the second axes; a control mechanism, axially sliding and angularly fixed with respect to the mast; and a connection element interposed between the control mechanism and the control element, sliding integrally with the control mechanism along the mast; the control mechanism comprises a first and a second rod; the rotor comprises a coupling, which is configured to enable/prevent rotation of the second rod with respect to the first rod when the torque exerted by the first connection element on the second rod about the first axis is greater/less than a threshold value in the event of failure of the connection element.

An aircraft is provided and includes an airframe having an upper section and a tail section, a main rotor assembly operably disposed at the upper section and one or more tail rotor assemblies operably disposed at the tail section. The one or more tail rotor assemblies respectively include one or more articulated propellers with thrust vectoring capability that are each independently rotatable about a respective variable rotational axis.

In one aspect, there is provided an aircraft, including a fuselage having a longitudinal axis extending from a front portion through an aft portion; first and second tail members extending from the aft portion; a first cross-flow fan system rotatably mounted to the first tail member; and a second cross-flow fan system rotatably mounted to the second tail member. The first and second cross-flow fan systems are configured to provide a forward thrust vector and an anti-torque vector on the aircraft. The first and second cross-flow fan systems can have a rotational axis oriented generally vertically. In another aspect, there is an aircraft including a fuselage having a front portion and a tail portion; and a cross-flow fan system supported by the tail portion. Embodiments include a cross-flow fan system retrofittable onto an aircraft and methods for retrofitting an aircraft with a cross-flow fan system.

An assembly is provided for a rotorcraft. This rotorcraft assembly includes a fuselage, a tail and a rotorcraft lift system. The tail boom is connected to and projects longitudinally out from the fuselage. The rotorcraft lift system includes a rotorcraft rotor and a powerplant configured to drive rotation of the rotorcraft rotor to generate rotorcraft lift. The powerplant includes a heat engine and a powerplant flowpath. The powerplant flowpath extends through the heat engine. The outlet from the powerplant flowpath is fluidly coupled to an interior volume in the tail boom.