An aircraft engine has a hollow driveshaft with a spool coaxial with the driveshaft and extending through the driveshaft to rotate independently of the driveshaft. A first harmonic cam is mounted on the driveshaft and a second spaced apart harmonic cam is mounted on the spool. At least one combustion cylinder is positioned between the cams along a combustion cylinder axis that is parallel with but radially spaced apart from the driveshaft. A piston assembly is disposed in each end of the combustion cylinder, with each piston assembly engaging a separate cam. A high-pressure compressor turbine is mounted on the driveshaft and driven by movement of a piston assembly, compressing air for the combustion cylinder. A rotating component is mounted on the spool and driven by movement of the other piston assembly. The rotating component may be another compressor turbine, a drive turbine, a fan or a propeller.

A cooling system for an aircraft comprises a gas turbine engine, an ancillary apparatus, and a heat exchanger. The gas turbine engine comprises, in axial flow sequence, a compressor module, a combustor module, and a turbine module, with a first electric machine being rotationally connected to the turbine module. The first electrical machine is configured to generate an electrical power P.sub.EM1 (W). The heat exchanger is configured to transfer a total waste heat energy Q (W) generated by the gas turbine engine and the ancillary apparatus, to an airflow passing through the heat exchanger, and a ratio S of: $S=\frac{\left(\mathrm{Total}\mathrm{Electrical}\mathrm{Power}\mathrm{Generated}=P_{\mathrm{EM}1}\right)}{\left(\mathrm{Total}\mathrm{Heat}\mathrm{Energy}\mathrm{Rejected}\mathrm{to}\mathrm{Airflow}=Q\right)}$
is in a range of between 0.50 and 5.00.

Turbine engine systems include a core assembly having a compressor section, a burner section, and a turbine section arranged along a shaft, with a core flow path through the turbine engine such that exhaust from the burner section passes through the turbine section and exits through a nozzle. A core condenser is arranged downstream of the turbine section and upstream of the nozzle and configured to condense water from the core flow path. A fuel cell is operably connected to the core assembly. A fuel source is configured to supply a fuel to each of the burner section for combustion and the fuel cell for reaction to generate electricity. At least one electric motor is operably coupled to the core assembly and configured to impart power to a portion of the core assembly and the fuel cell is configured to supply electrical power to the at least one electric motor.

A vehicle includes a gas turbine engine having at least two spools and an associated power system. The power system includes two independent power subsystems, including a first power subsystem for managing power transfer between spools and a second power subsystem for supplying a base power load to the vehicle. The first power subsystem has a first electric machine mechanically coupled with a first spool of the gas turbine engine and a second electric machine mechanically coupled with a second spool. The second electric machine is electrically coupled with the first electric machine such that electrical power is transmittable therebetween. The second power subsystem has a third electric machine mechanically coupled with one of the spools. The third electric machine is electrically coupled with a load positioned offboard the gas turbine engine. The first power subsystem and the second power subsystem are electrically decoupled from one another.

A vehicle includes a gas turbine engine having at least two spools and an associated power system. The power system includes two independent power subsystems, including a first power subsystem for managing power transfer between spools and a second power subsystem for supplying a base power load to the vehicle. The first power subsystem has a first electric machine mechanically coupled with a first spool of the gas turbine engine and a second electric machine mechanically coupled with a second spool. The second electric machine is electrically coupled with the first electric machine such that electrical power is transmittable therebetween. The second power subsystem has a third electric machine mechanically coupled with one of the spools. The third electric machine is electrically coupled with a load positioned offboard the gas turbine engine. The first power subsystem and the second power subsystem are electrically decoupled from one another.

A hybrid air mobility vehicle can make a long-distance flight through an efficient operation of an engine and a battery, and can reduce discomfort by reducing noise according to flight surroundings. The hybrid air mobility vehicle includes: an engine and a generator; a battery and a drive motor electrically connected to the generator; a first propeller connected to the drive motor and a second propeller connected to the generator through a clutch; and a controller that controls driving of the engine, the clutch, and the drive motor, based on a flight factor including at least one of a flight mode, a required power, a battery charging amount, or a surrounding flight environment of the hybrid air mobility vehicle.

A dual drive hybrid electric power plant to power an aircraft comprises a propulsion assembly, an internal combustion engine having an output shaft configured to drive the propulsion assembly, and an electric motor configured to drive the propulsion assembly and to be selectively coupled to the output shaft. The power plant may be configured such that the electric motor alone drives the propulsion assembly, or such that the internal combustion engine and the electric motor drive the propulsion assembly.

A powertrain control system is provided for a vertical take-off and landing aerial vehicle for urban air mobility. A powertrain of the vertical take-off and landing aerial vehicle is a hybrid type powertrain, in which the output shaft of a rotor driving motor is directly connected to a rotor, a battery is connected to the rotor driving motor to supply power thereto, and an engine and a generator are connected to a battery to charge and discharge the battery. The driving of the engine and the generator is controlled based on required power of the motor and the SOC of the battery in each flight step of the vertical take-off and landing aerial vehicle, and the SOC of the battery is constantly maintained at a predetermined level or higher.

A fuel pod for a hybrid electric aircraft. The fuel pod includes a housing, a fuel tank, a generator and a connection mechanism. The fuel tank is contained within the housing and is configured to hold a fuel therein. The generator is contained within the housing and is connected to the fuel tank. The generator is configured to power at least one of a plurality of flight components of a hybrid electric aircraft. The connection mechanism is at the housing and is configured to removably attach the fuel pod to the hybrid electric aircraft. The connection mechanism includes an electrical interface configured to electrically link to at least one of the plurality of flight components of the hybrid electric aircraft, and a communication interface configured to communicatively link to a flight controller communicatively connected to the hybrid electric aircraft.

A hybrid electric engine control module (ECU) can be configured to be operatively connected to a hybrid electric aircraft powerplant having a heat engine system and an electric motor system to control a torque output from each of the heat engine system and the electric motor system. The ECU can be configured to determine whether at least one of the electric motor system or the heat engine system are in a normal mode such that one of the electric motor system and/or the heat engine can provide a predetermined amount of torque. The ECU can be configured to switch to a degraded mode if either of the electric motor system or the heat engine system cannot provide the predetermined amount of torque. In the degraded mode the ECU can be configured to control the electric motor system and the heat engine system differently than in the normal mode or to not control one or both of the electric motor system or the heat engine system.