Often abbreviated as REF, the expeditionary fleet is comprised of United Earth Forces stationed away from the Earth.
The initial mission of the expedition was to establish and protect human colonies in space while searching for the homeworld of the Robotech Masters to take the conflict of the Robotech Wars away from the Earth. However, its focus shifted to reclaiming the Earth after the entire planet was overrun and occupied by the Invid.
The Robotech Expeditionary Force was first led by the SDF-3.
The Robotech Expeditionary Force returns with the SDF-4 to reclaim the Earth from Invid occupation.