An aircraft propulsion system comprising a reciprocating liquid cooled engine housed within the fuselage driving twin fuselage mounted ducted-fans is disclosed. The propulsion system may be liquid cooled with a liquid cooled exhaust and at least one turbocharger. The ducted-fans may run fan blade tip speeds of up to 97% Mach driven by a near constant RPM engine through a continuously variable transmission. The propulsion system may be low noise and may meet environmental standards typical in the automotive industry.

An aircraft heating assembly including an internal combustion engine having a liquid coolant system distinct from any fuel and lubricating system of the engine and including cooling passages in the internal combustion engine for circulating a liquid coolant from a coolant inlet to a coolant outlet, a coolant circulation path outside of the internal combustion engine and in fluid communication with the coolant inlet and the coolant outlet, and a heating element in heat exchange relationship with a portion of the aircraft to be heated. The coolant circulation path extends through a heat exchanger configured to remove a portion of a waste heat from the liquid coolant. The heating element is in heat exchange relationship with the coolant circulation path to receive another portion of the waste heat therefrom. A method of heating a portion of an aircraft is also discussed.

A battery heating system for a hybrid aircraft powertrain includes a combustion engine, a battery pack, a combustion engine coolant circuit, and a battery pack coolant circuit. The battery heating system further includes a heat exchanger configured to exchange heat between the combustion engine coolant circuit and the battery pack coolant circuit. The battery heating system further includes at least one throttling device operatively connected to one of the combustion engine coolant circuit or the battery pack coolant circuit. The battery heating system further includes a controller configured to transmit a signal to the at least one throttling device to adjust a flow of coolant through the heat exchanger of at least one of the combustion engine coolant circuit or the battery pack coolant circuit.

A method of cooling an aircraft power plant having a combustion engine is disclosed. The method comprises in a first operating mode, inducing a cooling air flow through a heat exchanger in an air conduit via a flow inducing device fluidly connected to the air conduit, the heat exchanger connected in heat exchange relationship with the power plant of the aircraft. The method comprises, in a second operating mode, bypassing the cooling air flow from the flow inducing device via a selectively closable air outlet of the air conduit downstream of the heat exchanger. A cooling system for an aircraft power plant is also disclosed.

An engine cooling system for a rotorcraft includes an engine having an engine cooling circuit, a hydraulic pump powered by the engine to pump hydraulic fluid, and a hydraulic circuit in fluid communication with the hydraulic pump and the engine cooling circuit, the hydraulic circuit including at least one hydraulic-powered component. The hydraulic pump is adapted to pump the hydraulic fluid through both the hydraulic circuit and the engine cooling circuit, thereby cooling the engine.

An aircraft propulsion system comprising a reciprocating liquid cooled engine housed within the fuselage driving twin fuselage mounted ducted-fans is disclosed. The propulsion system may be liquid cooled with a liquid cooled exhaust and at least one turbocharger. The ducted-fans may run fan blade tip speeds of up to 97% Mach driven by a near constant RPM engine through a continuously variable transmission. The propulsion system may be low noise and may meet environmental standards typical in the automotive industry.

An arrangement for cooling at least one power module of a power converter is disclosed herein. The arrangement includes power semiconductor components. The power module is arranged in a drive flow of an engine in such a way that the drive flow flows around cooling ribs of the power module. The disclosure also relates to a power converter, (e.g., an inverter), including an arrangement of this kind and an aircraft, (e.g., an airplane), including a power converter of this kind.

An aircraft propulsion system comprising a reciprocating liquid cooled engine housed within the fuselage driving twin fuselage mounted ducted-fans is disclosed. The propulsion system may be liquid cooled with a liquid cooled exhaust and at least one turbocharger. The ducted-fans may run fan blade tip speeds of up to 97% Mach driven by a near constant RPM engine through a continuously variable transmission. The propulsion system may be low noise and may meet environmental standards typical in the automotive industry.

Aircraft power plants and associated methods are provided. A method for driving a load on an aircraft includes: transferring motive power from an internal combustion (IC) engine to the load; discharging a flow of first exhaust gas from the IC engine when transferring motive power from the IC engine to the load; receiving the flow of first exhaust gas from the IC engine into a combustor; mixing fuel with the first exhaust gas in the combustor and igniting the fuel to generate a flow of second exhaust gas; receiving the flow of second exhaust gas at a turbine and driving the turbine with the flow of second exhaust gas from the combustor; and transferring motive power from the turbine to the load.

An aircraft engine assembly having a turbo-compounded internal combustion engine having an engine shaft. A coolant cooler is fluidly connected to a coolant circuitry of the internal combustion engine and to the environment. A plenum is connected with the environment via the coolant cooler and via an air outlet. A fan is disposed adjacent the air outlet and is operable to drive an airflow from the environment into the plenum via the coolant cooler. The fan is spaced apart from the internal combustion engine in a direction perpendicular to the engine shaft. A method of defining a cooling air circulation is also discussed.