System drive

The ship’s standard drive-1 spike drive is removed and replaced with a different propulsion system. The ship is still treated as having a drive-1 for maneuvering and system transit purposes, but it cannot make interstellar drills. This modification lowers the cost of the basic hull by 10% and adds extra power and space based on the size of the hull: 1 power for fighters, 2 for frigates, 3 for cruisers, and 4 for capital ship hulls. Twice this amount of free mass is gained by the process.