You don\'t need your core exposed (turrets require that no block is below the core, that doesn\'t apply to ships). But when you dock, unless things have changed, your ship will be placed with its core at a distance of (ship_max_height / 2) +1 from the docking module. This means if your core is on top of the ship, about half your ship will sink below the mothership\'s hangar floor. As a general rule, it is a good idea to have your core be placed at a height half that of the ship as a whole.