The invention relates to a rotor hub assembly for an electric fan, in particular for a radiator fan of a motor vehicle, comprising a hub cup, which rotates during operation and which has air outlet guides on the inside of the hub cup, which air outlet guides are arranged and shaped in such a way that the air outlet guides guide and accelerate cooling air, wherein a magnetic return cup is arranged inside the hub cup, which return cup has air passage openings, which, together with the air outlet guides, form continuous air outlets for a cooling air flow from the pressure side to the vacuum side of the fan. The invention further relates to an electric fan having such a rotor assembly.