An aircraft diesel engine may be operated at a minimal fuel rate. Shaft output power of the engine may be reduced by initiating combustion during the compression stroke. Combustion may be initiated during the compression stroke by advancing fuel injection, splitting fuel injection, and/or manipulating individual injection quantities. Initiating combustion during the compression stroke may slew torque generation to the compression stroke.

An aircraft diesel engine may be operated at a minimal fuel rate. Shaft output power of the engine may be reduced by initiating combustion during the compression stroke. Combustion may be initiated during the compression stroke by advancing fuel injection, splitting fuel injection, and/or manipulating individual injection quantities. Initiating combustion during the compression stroke may slew torque generation to the compression stroke.

An aircraft diesel engine may be operated at a minimal fuel rate. Shaft output power of the engine may be reduced by initiating combustion during the compression stroke. Combustion may be initiated during the compression stroke by advancing fuel injection, splitting fuel injection, and/or manipulating individual injection quantities. Initiating combustion during the compression stroke may slew torque generation to the compression stroke.

An aircraft diesel engine may be operated at a minimal fuel rate. Shaft output power of the engine may be reduced by initiating combustion during the compression stroke. Combustion may be initiated during the compression stroke by advancing fuel injection, splitting fuel injection, and/or manipulating individual injection quantities. Initiating combustion during the compression stroke may slew torque generation to the compression stroke.

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.

An aircraft includes a fuselage; a wing coupled to, and extending from, the fuselage; and a hybrid-electric propulsion system. The hybrid-electric propulsion system includes a power source including a combustion engine and an electric generator; a plurality of vertical thrust electric fans integrated into the wing and oriented to generate thrust along the vertical direction, the plurality of vertical thrust electric fans arranged along a length of the wing and driven by the power source; and a forward thrust propulsor. The forward thrust propulsor it is selectively or permanently mechanically coupled to the combustion engine.

An aircraft power plant has: a hybrid propulsion system having an electric motor, an output shaft drivingly connectable to a thrust generator, a combustion engine, a compressor, and a transmission having a first transmission drive path and a second transmission drive path selectively engageable to the first transmission drive path, the electric motor and the compressor in driving engagement with the first transmission drive path, the combustion engine and the output shaft in driving engagement with the second transmission drive path.

An aircraft power plant has a hybrid propulsion system having an electric motor, a combustion engine, an output shaft drivingly connectable to a thrust generator, a compressor, and a transmission having a first transmission drive path and a second transmission drive path, the combustion engine and the output shaft in driving engagement with the first transmission drive path, the electric motor selectively drivingly engageable to the compressor via either the first drive path or via the second drive path.

An aircraft power plant has a hybrid propulsion system having an electric motor, a combustion engine, an output shaft drivingly connectable to a thrust generator, a compressor, and a transmission having a first transmission drive path and a second transmission drive path, the combustion engine and the output shaft in driving engagement with the first transmission drive path, the electric motor selectively drivingly engageable to the compressor via either the first drive path or via the second drive path.

An aircraft power plant has a hybrid propulsion system having an electric motor, an output shaft drivingly connectable to a thrust generator, a combustion engine, a compressor, and a planetary gear train having an Auxiliary Power Unit (APU) mode in which the electric motor is in driving engagement with the compressor via the planetary gear train while the combustion engine is disengaged from the output shaft, and a propulsion mode in which the combustion engine and the electric motor are in driving engagement with the output shaft via the planetary gear train.