Provided is a high efficiency long range drone, and more particularly, a high efficiency long range drone capable of increasing flight time and efficiently using power during long range cruising flight by selectively using the power among an engine generator and a battery and applying an auxiliary wing.

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.

When a difference in the SOC among respective batteries is greater than or equal to a first prescribed value, an electric motor control section reduces output power of a cruise electric motor that operates using electric power of a battery with a low SOC and increases output power of a cruise electric motor that operates using electric power of a battery with a high SOC.

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.

One variation of a system for generating thrust at an aerial vehicle includes: a primary electric motor; a rotor coupled to the motor; an internal-combustion engine; a disengagement mechanism interposed between the motor and an output shaft of the internal-combustion engine; an cooling shroud defining a shroud inlet between the rotor and the internal-combustion engine, extending over the internal-combustion engine, and defining a cooling shroud outlet opposite the rotor; a cooling fan coupled and configured to displace air through the cooling shroud; and a local controller configured to receive a rotor speed command specifying a target rotor speed, adjust a throttle setpoint of the internal-combustion engine according to the target rotor speed and a state of charge of a battery in the aerial vehicle, and drive the primary electric motor to selectively output torque to the rotor and to regeneratively brake the rotor according to the target rotor speed.

One variation of a system for generating thrust at an aerial vehicle includes: a primary electric motor; a rotor coupled to the motor; an internal-combustion engine; a disengagement mechanism interposed between the motor and an output shaft of the internal-combustion engine; an cooling shroud defining a shroud inlet between the rotor and the internal-combustion engine, extending over the internal-combustion engine, and defining a cooling shroud outlet opposite the rotor; a cooling fan coupled and configured to displace air through the cooling shroud; and a local controller configured to receive a rotor speed command specifying a target rotor speed, adjust a throttle setpoint of the internal-combustion engine according to the target rotor speed and a state of charge of a battery in the aerial vehicle, and drive the primary electric motor to selectively output torque to the rotor and to regeneratively brake the rotor according to the target rotor speed.

An actuation system for an aircraft piston engine includes a controller and an actuator. The controller selectively supplies motor control signals to a motor. The actuator includes a housing, a motor, a main rod, a control handle, and an inner rod. The main rod receives a drive torque from the motor and translates in either a first axial direction or a second axial direction. The main rod is responsive to an axial drive force to translate in either the first axial direction or the second axial direction. The inner rod is disposed within the main rod and is movable between a first position, in which main rod rotation causes the main rod to translate, and a second position, in which main rod rotation does not cause the main rod to translate, but application of the axial force to the control handle causes the main rod to translate.

An actuation system for an aircraft piston engine includes a controller and an actuator. The controller selectively supplies motor control signals to a motor. The actuator includes a housing, a motor, a main rod, a control handle, and an inner rod. The main rod receives a drive torque from the motor and translates in either a first axial direction or a second axial direction. The main rod is responsive to an axial drive force to translate in either the first axial direction or the second axial direction. The inner rod is disposed within the main rod and is movable between a first position, in which main rod rotation causes the main rod to translate, and a second position, in which main rod rotation does not cause the main rod to translate, but application of the axial force to the control handle causes the main rod to translate.

A muffler (40) devised particularly for use with an engine of the type used on unmanned aerial vehicles (UAVs), and a UAV (10) having an engine (30) fitted with the muffler (40). The muffler (40) comprises a body (51) having an interior chamber (60). The muffler body (51) has a first end section (53) and a second end section (55). The first end section (51) is adapted for mounting onto the engine (31) by way of a first mount (81), with the interior chamber (60) in communication with an exhaust outlet of the engine (31) to receive exhaust flow therefrom. The second end section (53) is adapted to be mounted by way of a second mount (82) in a manner resisting movement with respect to the engine (31). In one arrangement, the second mount (82) is configured to yieldingly resist movement with respect to the engine (30). In another arrangement, the second mount (82) is configured to mount the second end section (55) under a preload resisting movement of the second end section with respect to the engine (30).