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.

An unmanned aerial vehicle capable of VTOL operation can include: a vehicle body defining longitudinal and transverse directions and opposing longitudinal sides; a first support boom coupled to the vehicle body at a first transverse axis and extending outwardly from the opposing longitudinal sides; a second support boom coupled to the vehicle body at a second transverse axis positioned rearward from the first transverse axis and extending outwardly from the opposing longitudinal sides; a plurality of electric motors coupled to a one of the first and second support booms, at least two electric motors of the plurality of electric motors positioned on each of the first and second support booms, a rotation axis of each of the at least two electric motors coupled to the second support boom offset in a transverse direction from a rotation axis of each of the at least two adjacent electric motors coupled to the first support boom; a plurality of rotors; and a propulsion system.

An unmanned aerial vehicle capable of VTOL operation can include: a vehicle body defining longitudinal and transverse directions and opposing longitudinal sides; a first support boom coupled to the vehicle body at a first transverse axis and extending outwardly from the opposing longitudinal sides; a second support boom coupled to the vehicle body at a second transverse axis positioned rearward from the first transverse axis and extending outwardly from the opposing longitudinal sides; a plurality of electric motors coupled to a one of the first and second support booms, at least two electric motors of the plurality of electric motors positioned on each of the first and second support booms, a rotation axis of each of the at least two electric motors coupled to the second support boom offset in a transverse direction from a rotation axis of each of the at least two adjacent electric motors coupled to the first support boom; a plurality of rotors; and a propulsion system.

Systems and methods for controlling flight via a parallel hybrid aircraft having an electric propulsion system and a combustion propulsion system are disclosed. Exemplary implementations may include: a combustion propulsion system including a combustion engine; an electric propulsion system including a motor and an electric power source, wherein the motor comprises a stator, a rotor coupled to the engine shaft, and support bearings between the rotor and the stator; a mechanical link coupled to the stator and the combustion engine, wherein the mechanical link substantially prevents movement of the stator in a rotational degree of freedom; and a propeller coupled to the engine shaft, wherein the rotor is coupled to the engine shaft between the propeller and the combustion engine.

Variations of an aerial vehicle, all with capability of vertical take-off and landing (VTOL), with one variation comprising at least three engines, at least three rotors, a flight control system, battery, and propulsion system. The second VTOL aerial vehicle variation being a hybrid with engine-powered rotors and electric-powered rotors configured to work with a flight control system and battery. The first and second variations having the option of a genset system which recharges the battery. The third VTOL aerial vehicle variation being all-electric-powered rotors configured to work with a flight control system and a genset system which powers the rotors and/or recharges the battery.

Variations of an aerial vehicle, all with capability of vertical take-off and landing (VTOL), with one variation comprising at least three engines, at least three rotors, a flight control system, battery, and propulsion system. The second VTOL aerial vehicle variation being a hybrid with engine-powered rotors and electric-powered rotors configured to work with a flight control system and battery. The first and second variations having the option of a genset system which recharges the battery. The third VTOL aerial vehicle variation being all-electric-powered rotors configured to work with a flight control system and a genset system which powers the rotors and/or recharges the battery.

Aircraft power plants including combustion engines, and associated methods for recuperating waste heat from such aircraft power plants are described. A method includes transferring the heat rejected by the internal combustion engine to supercritical CO.sub.2 (sCO.sub.2) used as a working fluid in a heat engine. The heat engine converts at least some the heat transferred to the sCO.sub.2 to mechanical energy to perform useful work onboard the aircraft.

Aircraft power plants including combustion engines, and associated methods for recuperating waste heat from such aircraft power plants are described. A method includes transferring the heat rejected by the internal combustion engine to supercritical CO.sub.2 (sCO.sub.2) used as a working fluid in a heat engine. The heat engine converts at least some the heat transferred to the sCO.sub.2 to mechanical energy to perform useful work onboard the aircraft.

A multicopter (100) having a plurality of propellers (1) is provided with electric motors (2), at least one main battery (3), a generator (4), and an engine (5). The electric motors (2) drive the propellers (1). The main battery (3) is a first electric power source that supplies the electric power to the electric motors (2). The generator (4) is a second electric power source that supplies the electric power to the electric motors (2). The engine (5) drives the generator (4). When a remaining capacity of the main battery (3) is less than a threshold, the generator (4) charges the main battery (3) with the electric power that has been converted from motive power from the engine (5).

A multicopter (100) having a plurality of propellers (1) is provided with electric motors (2), at least one main battery (3), a generator (4), and an engine (5). The electric motors (2) drive the propellers (1). The main battery (3) is a first electric power source that supplies the electric power to the electric motors (2). The generator (4) is a second electric power source that supplies the electric power to the electric motors (2). The engine (5) drives the generator (4). When a remaining capacity of the main battery (3) is less than a threshold, the generator (4) charges the main battery (3) with the electric power that has been converted from motive power from the engine (5).