Aircraft propulsion system with intermittent combustion engine and electric transmission system and method for operating the same

An aircraft, comprising:

• a fuselage;
• at least one nacelle having a gas flow path defined by an axially extending first airflow confining structure and an axially extending second airflow confining structure, wherein the first airflow confining structure defines a nacelle interior region and the second airflow confining structure is disposed radially outside of the first airflow confining structure;
• at least one propulsion system having:
• a compressor section powered by a first electric motor, the compressor section is disposed in the nacelle interior region and is configured to receive air entering the at least one nacelle, and configured to selectively produce a flow of compressor air at an air pressure greater than an ambient air pressure;
• an intermittent internal combustion (IC) engine configured to selectively intake the flow of compressor air during operation and produce an exhaust gas flow during operation, the intermittent IC engine disposed in the fuselage;
• a turbine section in communication with and configured to power a first electric generator configured to produce electrical power, wherein the turbine section is powered by the exhaust gas flow;
• a first fan rotationally driven by a second electric motor about a first rotational axis, the first fan having a first hub centered on the first rotational axis and a plurality of first fan blades extending radially outward from the first hub, wherein the first hub is disposed in the nacelle interior region of the at least one nacelle, and the plurality of first fan blades extend into the gas flow path of the at least one nacelle, wherein the first fan is positioned downstream of the compressor section;
• and
• an IC engine cooling system having at least one heat exchanger, a volume of coolant, coolant piping, and a pump configured to provide coolant communication between the intermittent IC engine and the at least one heat exchanger, the at least one heat exchanger disposed within the gas flow path of the at least one nacelle.

A method of powering an aircraft having a fuselage and at least one nacelle, the nacelle having an annular gas flow path defined by an axially extending first airflow confining structure and an axially extending second airflow confining structure, wherein the first airflow confining structure defines a nacelle interior region and the second airflow confining structure is disposed radially outside of the first airflow confining structure, the method comprising:

• driving a compressor section using a first electric motor to selectively produce a flow of compressor air at an air pressure greater than an ambient air pressure, the compressor section disposed radially inside of the first airflow confining structure and disposed to receive air entering the at least one nacelle;
• operating an intermittent internal combustion (IC) engine using the flow of compressor air to drive at least one first electric generator to produce electrical power and to produce an exhaust gas flow during operation, wherein the intermittent IC engine and the at least one electric generator are disposed in the fuselage;
• operating a turbine section to drive a second electric generator to produce electrical power, the turbine section powered using the exhaust gas flow;
• rotationally driving at least one fan about a rotational axis using a second electric motor powered by electrical power produced by the at least one first electrical generator, or the second electrical generator, or both, to force ambient air through the gas flow path, the fan having a first hub centered on the rotational axis and a plurality of fan blades extending radially outward from the hub, and the plurality of first fan blades extend into the gas flow path of the at least one nacelle, wherein the first fan is positioned downstream of the compressor section;
• and
• pumping a volume of coolant through a cooling system having at least one heat exchanger, coolant piping, and a pump, the IC engine cooling system configured to provide coolant communication between the intermittent IC engine and the at least one heat exchanger, the at least one heat exchanger disposed within the gas flow path of the at least one nacelle.