A system is described that includes a turbine engine including an engine fan including one or more variable-pitch blades driven by a shaft, which rotates at a rotational speed which depends on a pitch of the one or more variable-pitch blades of the engine fan. The system further includes a generator configured to produce alternating-current (AC) electricity at a particular frequency relative to the rotational speed of the shaft. The system also includes a propulsor, which includes a propulsor motor and a propulsor fan. The propulsor motor is configured to drive, based on the AC electricity produced by the generator, the propulsor fan. The system includes a controller configured to control the particular frequency of the AC electricity by at least controlling the pitch of the one or more variable-pitch blades of the engine fan and thereby the rotational speed of the generator.