The massive Baikal-class Force Projection Vessel is a warship that, externally, resembles a large cruiser or dreadnought, but is actually an assault vessel, designed to execute planetary or even system-wide ground invasions. The ship uses massive nuclear powered turbine engines to provide enough vertical lift to land on planets, and carries hundreds of shuttlecraft and ground vehicles.
More information on the lore behind this ship is available at the
wiki here