The Union Tug Albatross is a large trainlike spacecraft that appears in the Story Mode.
It's main purpose in the story is to collect and carry Rift Energy throughout the Outer Spur, delivering it to wherever it goes once collected. However, during a mission, the Tug self destructs to keep the Outcasts from getting their hands on an engine that is capable of jumping from system to system.
In terms of its technical aspects, the Union Tug appears to work like a long train in space, with several dozen crate like cars connected to each other. Primarily, it is used for carrying Rift Energy and other supplies across the Outer Spur. Based on the size and length of the Tug, it probably jumps from station to station instead of freeflying like a normal spacecraft. They appear to be unarmed for the most part, although it can be assumed that there may be some armed variants.