Tail boom drive systems for helicopters are described which utilize a fan internal to the tail boom to provide yaw control, and an external propulsor to provide forward thrust. In one embodiment, the tail boom drive system includes a shaft, a fan, and a propulsor. The shaft is disposed lengthwise within an interior space of the tail boom, and the shaft has a first end and a second end. The fan is mechanically coupled coaxially to the shaft within the interior space between the first end and the second end, and the fan generates a variable airflow directed towards the second end that is ejected from the interior space substantially perpendicular to the tail boom. The propulsor is external to the tail boom and is mechanically coupled coaxially to the shaft at the second end, and the propulsor generates a variable thrust directed towards the first end.

The present invention relates to a device for controlling the yaw of an aviation device, such as a helicopter, said aviation device comprising a bearing structure and a rotating member connected to the bearing structure to be mobile in rotation, around an axis of rotation, relative to said bearing structure, wherein the rotating member comprises fixing means for fixing at least one blade, the yaw control device comprising a rotor and a stator which form, in combination, an electrical machine, wherein the bearing structure is connected to the first of this stator and this rotor, and wherein the rotating member is connected to the second of this stator and this rotor, wherein the electrical machine is suitable for generating an electromotive force applied to the rotating member.

A duct configured with a fan to increase thrust. The duct includes an interior surface configured to surround a rotation axis of the fan. The interior surface includes a nozzle portion configured to be located upstream of the fan and a diffuser portion configured to be located downstream of the fan. The interior surface defines an opening configured to introduce additional airflow along the diffuser portion.

A rotorcraft with counter-rotating rotor blades can hover in place, translate forwards, backwards, or side-to-side irrespective of the airspeed over the rotorcraft. The rotorcraft includes a fuselage, a first axial-flow rotor, a radial-flow rotor, a propulsion funnel, and a plurality of lift funnels. The fuselage is used to house passengers, cargo, flight electronics, and or fuel. The first axial-flow rotor rotates independent of the radial-flow rotor and generates forward thrust for propelling the rotorcraft. The radial-flow rotor in the opposite direction of the first axial-flow rotor and generates upward thrust for lifting the rotorcraft. The airflow generated by the first axial-flow rotor travels through the propulsion funnel and exits out of the back of the rotorcraft. The airflow generated by the radial-flow rotor travels through the plurality of lift funnels which gradually directs the airflow downwards.

A rotorcraft comprises a fuselage, a tail boom, a rotor system, and a centrifugal blower system. The centrifugal blower system comprises a centrifugal blower configured to generate thrust using an airflow, wherein the centrifugal blower is located within the tail boom. The centrifugal blower system also comprises a plurality of ducts configured to control the thrust generated by the centrifugal blower, wherein the plurality of ducts is located on a portion of the tail boom surrounding the centrifugal blower, and wherein the plurality of ducts comprises one or more adjustable ducts configured to vary a size of an associated duct opening.

A helicopter has a fuselage, a main rotor system connected to the fuselage and configured to rotate in a rotor direction, the main rotor system comprising a retreating rotor blade side and an opposing advancing rotor blade side, and a first wing extending from the fuselage on the retreating rotor blade side. The helicopter comprises no tail rotor system and comprises no counter-rotating rotor system coaxial with the main rotor system.

Electrically powered Vertical Take-off and Landing (VTOL) aircraft are presented. Contemplated VTOL aircraft can include one or more electrical energy stores capable of delivering electrical power to one or more electric motors disposed within one or more propeller housings, where the motors can drive the propellers. The VTOL aircraft can also include one or more back-up and/or secondary energy/power sources (e.g., batteries, engines, generators, fuel-cells, semi-cells, etc.) capable of driving the motors should the energy stores fail or deplete. The VTOL aircraft will be significantly different to regular Tiltrotor aircraft as we use propellers and a modern steering system that reduces complicity dramatically. The contemplated configurations address safety, noise, and hover stability and outwash concerns to allow such designs to operate in built-up areas while retaining competitive performance relative to existing aircraft.

A rotorcraft with counter-rotating rotor blades can hover in place, translate forwards, backwards, or side-to-side irrespective of the airspeed over the rotorcraft. The rotorcraft includes a fuselage, a first axial-flow rotor, a radial-flow rotor, a propulsion funnel, and a plurality of lift funnels. The fuselage is used to house passengers, cargo, flight electronics, and or fuel. The first axial-flow rotor rotates independent of the radial-flow rotor and generates forward thrust for propelling the rotorcraft. The radial-flow rotor in the opposite direction of the first axial-flow rotor and generates upward thrust for lifting the rotorcraft. The airflow generated by the first axial-flow rotor travels through the propulsion funnel and exits out of the back of the rotorcraft. The airflow generated by the radial-flow rotor travels through the plurality of lift funnels which gradually directs the airflow downwards.

An aircraft engine assembly having a turbo-compounded internal combustion engine having an engine shaft. A coolant cooler is fluidly connected to a coolant circuitry of the internal combustion engine and to the environment. A plenum is connected with the environment via the coolant cooler and via an air outlet. A fan is disposed adjacent the air outlet and is operable to drive an airflow from the environment into the plenum via the coolant cooler. The fan is spaced apart from the internal combustion engine in a direction perpendicular to the engine shaft. A method of defining a cooling air circulation is also discussed.

In some embodiments, a rotorcraft includes a fuselage, a tailboom, a drive system and a variable thrust cross-flow fan system. The cross-flow fan system includes a cross-flow fan assembly that is mechanically coupled to a drive shaft and operable to rotate with the drive shaft about a longitudinal axis. The cross-flow fan assembly includes first and second driver plates having a plurality of blades rotatably mounted therebetween. The blades are disposed radially outwardly from the longitudinal axis and have a generally circular path of travel when the cross-flow fan assembly rotates about the longitudinal axis. The blades are moveable between a plurality of pitch angle configurations. A control assembly is coupled to the blades. The control assembly is operable to change the pitch angle configuration of the blades to generate variable thrust at a substantially constant rotational speed of the cross-flow fan assembly.