Balancing a drone is difficult with engines, when drones are equipped with engines to increase the flight time. However, balancing the drone can be made easy by providing the drone with an electric motor or an electric motor that involves a generator feature.

A thrust assembly motor is described, which can be used in a distributed electric propulsion system. The thrust assembly motor may include a revolved-wedge shaped ring on a leading edge of a motor stator, with a row of axial stator blades extending therefrom. The revolved-wedge shaped ring provides a mounting surface for the axial stator blade row while also controlling the ratio of airflow mass entering the outer gap versus the inner gap. The axial stator blade row, mounted to the revolved-wedge shaped ring, is configured to convert tangential kinetic energy (i.e., associated with a velocity component of the airflow) in the cooling airflow aft of the cooling fan rotors into static pressure rise after interaction with the axial stator blade row, during flight of the hybrid-propulsion aircraft.

There is disclosed an aircraft including a fuselage extending along a longitudinal axis; forward swept wings extending from the fuselage; at least one horizontal stabilizer secured to the fuselage; and a distributed electrical propulsion system operatively connected to an electrical power source. The distributed electrical propulsion system have an air intake located rearward of an intersection between the forward swept wings and the fuselage open to a boundary layer region on a surface of the fuselage.

UAV configurations and battery augmentation for UAV internal combustion engines, and associated systems and methods are disclosed, A representative configuration includes a fuselage, first and second wings coupled to and pivotable relative to the fuselage, and a plurality of lift rotors carried by the fuselage. A representative battery augmentation arrangement includes a DC-powered motor, an electronic speed controller, and a genset subsystem coupled to the electronic speed controller. The genset subsystem can include a battery set, an alternator, and a motor-gen controller having a phase control circuit configurable to rectify multiphase AC output from the alternator to produce rectified DC feed to the DC-powered motor. The motor-gen controller is configurable to draw DC power from the battery set to produce the rectified DC feed.

A hybrid electric propulsion system may include an independent speed variable frequency (ISVF) generator coupled to an alternating current (AC) bus via a first switch. The system may further include a variable frequency independent speed (VFIS) motor coupled to the AC bus via a second switch, the system omitting circuitry to perform a full-power rated power conversion between the ISVF generator and the VFIS motor. The system may also include an alternating current direct current (AC/DC) converter coupled to the AC bus via a third switch. The system may include a battery coupled to the AC/DC converter.

An aircraft includes an aircraft heat source; a propulsion system including an electric propulsion engine, the electric propulsion engine including an electric motor and a fan rotatable by the electric motor, the electric propulsion engine further defining a fan air flowpath; a thermal management system including a heat source exchanger in thermal communication with the aircraft heat source, a heat sink exchanger in thermal communication with the fan air flowpath of the electric propulsion engine, and a thermal distribution bus extending from the heat source exchanger to the heat sink exchanger; and a control system operably connected to the thermal management system for selectively thermally coupling the heat sink exchanger with the heat source exchanger.

A hybrid-electric propulsion system for an aircraft includes a propulsor and a turbomachine. The turbomachine includes a high pressure turbine drivingly coupled to a high pressure compressor through a high pressure spool. The hybrid electric propulsion system further includes an electrical system including a first electric machine, a second electric machine, and an electric energy storage unit electrically connectable to the first and second electric machines. The first electric machine is coupled to the high pressure spool of the turbomachine and the second electric machine is coupled to the propulsor for driving the propulsor to provide a propulsive benefit for the aircraft. The hybrid electric propulsion system also includes a controller configured to provide electrical power from an electric power source to the first electric machine to drive the first electric machine to start, or assist with starting, the turbomachine.

A rotor blade rotation system includes two or more rotor blades, each rotor blade in mechanical communication with a hub and pivotable about an axis of rotation, a bearing plate comprising a rotating portion and a non-rotating portion, a fold linkage coupled to the rotating portion of the bearing plate and in mechanical communication with the rotor blade, and an actuator coupled to the non-rotating portion of the bearing plate and operable to reposition the bearing plate from a first position to a second position such that the folding links pivot the rotor blades from a deployed position to a forward folded position.

A propulsion system for an aircraft includes an electric propulsion engine. The electric propulsion engine includes an electric motor and a fan rotatable about a central axis of the electric propulsion engine by the electric motor. The electric propulsion engine also includes a bearing supporting rotation of the fan and a thermal management system. The thermal management system includes a lubrication oil circulation assembly and a heat exchanger thermally connected to the lubrication oil circulation assembly. The lubrication oil circulation assembly is configured for providing the bearing with lubrication oil. Such an electric propulsion engine may be a relatively self-sufficient engine.

An aircraft of a modular type including: at least one rotor suitable for providing in full or in part propulsion and/or lift for the aircraft; at least one power plant of the combustion engine type or of the electric motor type; a main gearbox, for mechanically transmitting drive torque generated by the at least one power plant to the at least one rotor; and an avionics system for assisting in piloting the aircraft. In accordance with the invention, the avionics system is configured for automatically providing the assistance in piloting the aircraft when the aircraft has a first power plant only or when the aircraft has a first power plant and a second power plant.