A power management system for a multi engine rotorcraft having a main rotor system with a main rotor speed. The power management system includes a first engine that provides a first power input to the main rotor system. A second engine selectively provides a second power input to the main rotor system. The second engine has at least a zero power input state and a positive power input state. A power anticipation system is configured to provide the first engine with a power adjustment signal in anticipation of a power input state change of the second engine during flight. The power adjustment signal causes the first engine to adjust the first power input to maintain the main rotor speed within a predetermined rotor speed threshold range during the power input state change of the second engine.

The present disclosure is directed to an aerodynamic stabilizer assembly for stabilizing an aft fan mounted to a fuselage of an aircraft. For example, the stabilizer assembly includes one or more generally horizontal stabilizers for mounting to a nacelle of the aft fan and the fuselage so as to stabilize the aft fan. Each of the generally horizontal stabilizers includes an inner portion and an outer portion. As such, the inner portions are mounted to a nacelle of the aft fan and the fuselage at a predetermined downward angle with respect to a central axis of the aft fan so as to direct airflow upwards and into the aft fan, the outer portion being mounted to the inner portion.

In order to further benefit from the principle of boundary layer ingestion by engines of an aircraft assembly, the rear portion of the fuselage of this aircraft assembly includes a front portion which splits up into at least two distinct rear portions, spaced apart from each other, and each integrating the rotary ring of the receiver of one of the engines.

In order to further benefit from the principle of boundary layer ingestion by engines of an aircraft assembly, the rear portion of the fuselage of this aircraft assembly includes a front portion which splits up into at least two distinct rear portions, spaced apart from each other, and each integrating the rotary ring of the receiver of one of the engines.

A propulsion system of an aircraft has at least one unducted fan and at least one ducted fan, the at least one unducted fan and the at least one ducted fan being powered by an electric power source and rotatable between a vertical thrust position and a forward thrust position, and a controller configured to distribute electrical power between the at least one unducted fan and the at least one ducted fan. During a first mode when the at least one unducted fan and the at least one ducted fan are in the vertical thrust position, the controller is configured to distribute the electrical power between the plurality of unducted fans and the plurality of ducted fans such that the at least one unducted fan is a primary source of thrust.

A propulsion system of an aircraft has at least one unducted fan and at least one ducted fan, the at least one unducted fan and the at least one ducted fan being powered by an electric power source and rotatable between a vertical thrust position and a forward thrust position, and a controller configured to distribute electrical power between the at least one unducted fan and the at least one ducted fan. During a first mode when the at least one unducted fan and the at least one ducted fan are in the vertical thrust position, the controller is configured to distribute the electrical power between the plurality of unducted fans and the plurality of ducted fans such that the at least one unducted fan is a primary source of thrust.

A tiltrotor aircraft comprising a wing carrying an engine on each wing half, and a fuselage-mounted third engine with a transmission system configured to drive each of the tilting rotors from the third engine. The engines may be any powerplant, including fore example, a reciprocating engine, a turbine engine, or an electric motor. The third engine is preferably controlled for best efficiency and best safety in engine failure cases.

An aircraft is equipped with multiple fans for boundary layer ingestion. The aircraft comprises a fuselage, having an exterior surface and a rearward-most end. The aircraft also comprises a plurality of fans that are fixed to and positioned about the exterior surface of the fuselage at an axial location forward of the rearward-most end of the fuselage. Each one of the plurality of fans comprises a plurality of fan blades and a fan drive configured to rotate the plurality of fan blades. The plurality of fan blades are positioned at lateral locations relative to the exterior surface of the fuselage such that when rotated by the fan drive the plurality of fans receive and accelerate fuselage boundary layer air flow, along the exterior surface of the fuselage, from a first average velocity to a second average velocity, greater than the first average velocity, when the aircraft is in flight.

To reduce the overall mass of an engine assembly for aircraft, this assembly comprises a part of the fuselage of an aircraft, a turbomachine comprising an unfaired propeller, together with an annular row of unfaired after-guide vanes located aft of the propeller and rotationally fixed in relation to a longitudinal axis of the turbomachine, and a mounting pylon. At least part of the leading edge of the pylon is incorporated within the annular row between two after-guide vanes.