Abstract: A propulsion system for an aircraft is provided. The propulsion system includes an engine including a first input shaft and a drivetrain coupled to the first input shaft. The drivetrain includes an output shaft, a gear assembly, an electric motor, and a second input shaft. The gear assembly includes a main gear mounted to the output shaft, and a bevel ring gear integrated on a face of the main gear. The main gear, the bevel ring gear, and the output shaft are rotatable about a first rotational axis. The electric motor includes a rotor rotatable about a second rotational axis. The second rotational axis is perpendicular to the first rotational axis. The second input shaft couples the rotor to the bevel ring gear. The second input shaft is rotatable about the second rotational axis.

Abstract: A system is provided for an aircraft. This aircraft system includes a powertrain, a lubrication system and a casing. The powertrain includes a powerplant, a power transmission, a clutch system and a bladed rotor. The power transmission operatively couples the powerplant to the clutch system. The clutch system operatively couples the power transmission to the bladed rotor. The powerplant is configured to drive rotation of the bladed rotor through the power transmission and the clutch system when the clutch system is engaged. The lubrication system includes a lubricant reservoir and a lubricant circuit. The lubrication system is configured to direct lubricant from the lubricant reservoir to the powerplant and the power transmission through the lubricant circuit. The casing houses the power transmission and the lubricant reservoir.

Abstract: A system is provided for an aircraft. This aircraft system includes a powertrain, a lubrication system and a casing. The powertrain includes a powerplant, a power transmission, a clutch system and a bladed rotor. The power transmission operatively couples the powerplant to the clutch system. The clutch system operatively couples the power transmission to the bladed rotor. The powerplant is configured to drive rotation of the bladed rotor through the power transmission and the clutch system when the clutch system is engaged. The lubrication system includes a lubricant reservoir and a lubricant circuit. The lubrication system is configured to direct lubricant from the lubricant reservoir to the powerplant and the power transmission through the lubricant circuit. The casing houses the power transmission and the lubricant reservoir.