A propulsion engine for an aeronautical vehicle defining a radial direction and an air flowpath, the propulsion engine comprising: a power source; and a fan comprising a fan blade rotatable by the power source and extending generally along the radial direction, the fan blade defining an inlet, an outlet, and an air passage extending between the inlet and the outlet and in airflow communication with the air flowpath, the inlet being positioned inward from the outlet along the radial direction to provide an airflow through the air flowpath; wherein the power source is an electric machine comprising a rotor and a stator, wherein the air flowpath is a cooling air flowpath of the propulsion engine, defined at least in part by the electric machine, and is in thermal communication with the stator of the electric machine, wherein the fan blade is attached to the rotor of the electric machine, wherein the propulsion engine comprises a cowling, wherein the power source is positioned within the cowling, and wherein the inlet of the fan blade is also positioned within the cowling, wherein the cowling defines an opening positioned aft of the fan blade of the fan, wherein the air flowpath extends between a first end and a second end, wherein the first end is in airflow communication with the opening of the cowling, and wherein the second end is in airflow communication with the inlet of the fan blade, wherein the fan blade of the fan defines an inner end and an outer end along the radial direction, wherein the inlet is defined at the inner end, wherein the outlet is defined at the outer end, wherein the outer end of the fan blade is coupled to the rotor of the electric machine, and wherein the fan is configured to provide the airflow to the air flowpath of the electric machine. a power source; and a fan comprising a fan blade rotatable by the power source and extending generally along the radial direction, the fan blade defining an inlet, an outlet, and an air passage extending between the inlet and the outlet and in airflow communication with the air flowpath, the inlet being positioned inward from the outlet along the radial direction to provide an airflow through the air flowpath; wherein the power source is an electric machine comprising a rotor and a stator, wherein the air flowpath is a cooling air flowpath of the propulsion engine, defined at least in part by the electric machine, and is in thermal communication with the stator of the electric machine, wherein the fan blade is attached to the rotor of the electric machine, wherein the propulsion engine comprises a cowling, wherein the power source is positioned within the cowling, and wherein the inlet of the fan blade is also positioned within the cowling, wherein the cowling defines an opening positioned aft of the fan blade of the fan, wherein the air flowpath extends between a first end and a second end, wherein the first end is in airflow communication with the opening of the cowling, and wherein the second end is in airflow communication with the inlet of the fan blade, wherein the fan blade of the fan defines an inner end and an outer end along the radial direction, wherein the inlet is defined at the inner end, wherein the outlet is defined at the outer end, wherein the outer end of the fan blade is coupled to the rotor of the electric machine, and wherein the fan is configured to provide the airflow to the air flowpath of the electric machine.