3d movement

Hey all, I have been searching the forum to see if there is a way to move things up/down in the game? It seems like the ships sometimes do this on their own, but I have no way of controlling it. I would like to be able to build gun enplacements up and down along a flight path, not just on the same level? Am I missing something in the controls?? I went through the tutorial again and it said nothing about moving up or down. Thanks.