ship-stealthy ship-stealthy Causes the ships listed in this sexpression to become stealth ships (i.e. invisible to radar). Takes 1 or more arguments... All: Name of ships to make stealthy.
Besides the obvious, this and ship-unstealthy can be use to simulate various kinds of sensor and targeting problems by repeatedly stealthing and unstealthing enemy ships as they are targeted by the player. A example of how to do just that is available here.