Abstract: A bowed rotor prevention system for a gas turbine engine includes a bowed rotor prevention motor. A motor shaft of the bowed rotor prevention motor is operable to drive rotation of the gas turbine engine through an engine accessory gearbox. The motor shaft interfaces with an air turbine operable to rotate an output shaft mechanically linked to the engine accessory gearbox. The bowed rotor prevention system also includes a controller operable to engage the bowed rotor prevention motor and drive rotation of the gas turbine engine below an engine starting speed until a bowed rotor prevention threshold condition is met.