Aerial warships are incredibly large, dwarfing the size of transport aircraft. They feature multiple propulsion systems (usually many high-powered engines) in order to maintain flight. However, their sizes make aerial warships easy targets for precision attacks by smaller jet fighters; destruction of an aerial warship typically involves destroying their source of thrust, forcing them to crash into the ground. A sub-class of aerial warships is the heavy command cruiser, an official description that has been used to refer to aerial warships that can act as mobile command bases.