Abstract: A hybrid drive system can include a shaft, an electrical machine comprising a rotor and a stator, and a mechanical disconnect system connecting the rotor to the shaft. The mechanical disconnect system is configured to mechanically connect the rotor to the shaft in a first state and to mechanically disconnect the rotor from the shaft in a second state such that rotor does not drive the shaft or such that the rotor is not driven by the shaft. The rotor can be a permanent magnet rotor, for example.

Abstract: An integrated turbo-compressor includes a compressor with a compressor outlet, a turbine with a turbine inlet, the turbine operatively connected to the compressor by an interconnect shaft, and a compounding drive. The compounding drive is connected to the turbine and has a variable gear ratio and an output member, the variable gear ratio coupling the turbine to the output member to compound output of an internal combustion engine using energy recovered from an exhaust flow received from the internal combustion engine and in excess of energy required to compress combustion air provided to the internal combustion engine. Internal combustion engines, aircraft, and methods of compounding output of internal combustion engines are also described.

Abstract: A hybrid drive system can include a shaft, an electrical machine comprising a rotor and a stator, and a mechanical disconnect system connecting the rotor to the shaft. The mechanical disconnect system is configured to mechanically connect the rotor to the shaft in a first state and to mechanically disconnect the rotor from the shaft in a second state such that rotor does not drive the shaft or such that the rotor is not driven by the shaft. The rotor can be a permanent magnet rotor, for example.

Abstract: An aircraft propulsion system includes a hybrid-electric power plant for delivering power to an air mover for propelling an aircraft. The hybrid-electric power plant includes a heat engine operatively connected to a first air mover, and an electric motor operatively connected to a second air mover. The second air mover is positioned on a wing of the aircraft outboard from the heat engine. A method for reducing trailing vortices includes powering a first air mover of an aircraft with a heat engine during a take-off stage, a climb stage, a cruise-stage and/or a descent stage. The method includes powering a second air mover of the aircraft with an electrical motor during the take-off stage and/or the climb stage. The method includes freewheeling the second air mover during the cruise stage and/or the descent stage to generate mechanical energy and reduce wing tip vortices.

Abstract: A system includes a variable displacement pump (VDP) with an inlet and an outlet, a fixed displacement motor (FDM) with an inlet and an outlet. A first line connects the outlet of the VDP to the inlet of the FDM. A second line connects the outlet of the FDM to the inlet of the VDP. A crossover line is in fluid communication between the first and second lines, with a valving system in the crossover line configured so that the flow through the crossover line can switch directions to allow a change in power flow direction between the FDM and the VDP.

Abstract: A hybrid electric aircraft powerplant arrangement can include a first wing pair of powerplants for a first wing of an aircraft, the first wing pair comprising a first electric powerplant configured to drive a first air mover and a first heat engine powerplant configured to drive a second air mover separate from the first air mover. The arrangement can include a second wing pair of powerplants for a second wing of the aircraft, the second wing pair comprising a second electric powerplant configured to drive a third air mover separate from the first and second air movers, and a second heat engine powerplant configured to drive a fourth air mover separate from the first, second, and third air movers.

Abstract: A method of taxiing an aircraft on the ground including providing throttle power to a first air mover using an electric motor of a hybrid-electric powerplant while the aircraft is on the ground and mobilizing the aircraft using only power from the electric motor.

Abstract: A hybrid electric aircraft powerplant controller for controlling an engine and an electric motor-generator can include an engine recharging module. The engine recharging module can be configured to operate the engine to produce a desired output power to a propulsor and to produce additional power to drive the electric motor-generator to produce electrical output from the electric motor-generator to recharge an electrical storage device during at least one power setting and/or flight phase where the electric motor-generator is not driving the propulsor.

Abstract: A cooling system includes a thermal engine having a fluid output, and a motor drive having a fluid inlet in fluid communication with the fluid output of the thermal engine. The fluid inlet of the motor drive is downstream from the fluid output of the thermal engine. The system includes a fluid storage downstream from the motor drive and a fluid output of the motor drive. A method of cooling a motor drive includes outputting a cooling fluid from a fluid output of a thermal engine, receiving the cooling fluid from the fluid output of the thermal engine in a fluid inlet of a motor drive, passing the cooling fluid through the motor drive to a fluid output of the motor drive, receiving the cooling fluid in a fluid storage.

Abstract: A hybrid drive system can include a shaft, an electrical machine comprising a rotor and a stator, and a mechanical disconnect system connecting the rotor to the shaft. The mechanical disconnect system is configured to mechanically connect the rotor to the shaft in a first state and to mechanically disconnect the rotor from the shaft in a second state such that rotor does not drive the shaft or such that the rotor is not driven by the shaft. The rotor can be a permanent magnet rotor, for example.

Abstract: An integrated turbo-compressor includes a compressor with a compressor outlet, a turbine with a turbine inlet, the turbine operatively connected to the compressor by an interconnect shaft, and a compounding drive. The compounding drive is connected to the turbine and has a variable gear ratio and an output member, the variable gear ratio coupling the turbine to the output member to compound output of an internal combustion engine using energy recovered from an exhaust flow received from the internal combustion engine and in excess of energy required to compress combustion air provided to the internal combustion engine. Internal combustion engines, aircraft, and methods of compounding output of internal combustion engines are also described.

Abstract: A compounding drive includes an input member, an epicyclical gear arrangement connected to the input member, an output member connected to the epicyclical gear arrangement, and a hydraulic pump/motor set. The hydraulic pump/motor set connects the epicyclical gear arrangement to the output member through an overrunning clutch for unidirectional communication of mechanical rotation between the input member and the output member. Engine arrangements, aircraft, and methods of compounding internal combustion engines are also described.

Abstract: A hybrid propulsion system can include an electric motor configured to convert electrical energy into motion, a battery configured to store electrical energy and operatively connected to the electric motor to provide a battery output to the electric motor and a generator configured to convert non-electrical energy into electrical energy, the generator operatively connected to the electric motor to provide a generator output to the motor simultaneously with the battery output. The system can include a controller operatively connected to the generator and configured to control the generator output of the generator as a function one or more of a state of the battery or the battery output.

Abstract: A cooling arrangement for an electrical machine includes a stator including a stack defining a rotation axis and windings in the stack extending parallel to the rotation axis and forming end windings where the windings wrap around opposing axial ends of the stack. A rotor is included radially inward from the stator, configured to rotate about the rotation axis relative to the stator. An annular cooling jacket is included radially outward from the end windings at one axial end of the stack. The cooling jacket is configured to circulate cooling fluid in an internal flow passage therein in a circumferential direction to carry heat away from the end windings.

Abstract: A gas turbine engine including: a tail cone; a low pressure compressor; a low pressure turbine; a low speed spool interconnecting the low pressure compressor and the low pressure turbine; and an electric generator located within the tail cone, the electric generator being operably connected to the low speed spool; a structural support housing at least partially enclosing the electric generator, the structural support housing being located within the tail cone; and a temperature control device located within the tail cone between the structural support housing and the tail cone, wherein the temperature control device is in thermal communication with at least one of the structural support housing and the tail cone.

Abstract: A gas turbine engine including: a tail cone; a low pressure compressor; a low pressure turbine; a low speed spool interconnecting the low pressure compressor and the low pressure turbine; and an electric generator located within the tail cone, the electric generator being operably connected to the low speed spool, wherein the electric generator includes a coolant cavity in thermal communication with one or more components of the electric generator; a structural support housing at least partially enclosing the electric generator, the structural support housing including a forward wall located on a forward end of the structural support housing, wherein the forward wall includes a first opening; a first coolant conveying tube extending through the first opening to fluidly connect to the coolant cavity; and a first electrical connector tube extending through the first opening within the first coolant conveying tube to electrically connect to the electric generator.

Abstract: A gas turbine engine including: a tail cone; a low pressure compressor; a low pressure turbine; a low speed spool interconnecting the low pressure compressor and the low pressure turbine; an electric generator located within the tail cone, the electric generator being operably connected to the low speed spool; a structural support housing at least partially enclosing the electric generator, the structural support housing being located within the tail cone; and a mounting system located within the tail cone between the structural support housing and the tail cone, wherein the mounting system attaches the tail cone to the structural support housing.

Abstract: A gas turbine engine including: a tail cone; a low pressure compressor; a low pressure turbine; a low speed spool interconnecting the low pressure compressor and the low pressure turbine; and an electric generator located within the tail cone, the electric generator being operably connected to the low speed spool; and one or more acoustic panel assemblies located around the electric generator, the one or more acoustic panel assemblies including: an acoustic backing sheet, an outer porous liner, and an acoustic liner interposed between the outer porous liner and the acoustic backing sheet.

Abstract: Provided are embodiments of a system including a series hybrid architecture using compounded doubly fed induction machines. Embodiments include a controller configured to control the operation of the system, and a power source configured to convert a first form of energy to a second form of energy. Embodiments also include a first machine configured to generate power, wherein the first machine is mechanically coupled to the power source, and a second machine configured to control equipment, wherein the first machine is electrically coupled to the second machine. Embodiments further include methods for operating the series hybrid architecture using the compounding doubly fed induction machines.

Abstract: A hybrid drive system can include a shaft, an electrical machine comprising a rotor and a stator, and a mechanical disconnect system connecting the rotor to the shaft. The mechanical disconnect system is configured to mechanically connect the rotor to the shaft in a first state and to mechanically disconnect the rotor from the shaft in a second state such that rotor does not drive the shaft or such that the rotor is not driven by the shaft. The rotor can be a permanent magnet rotor, for example.