I'm trying to make a physics based spacecraft movement but I can't seem to figure out how to thrust the "spaceship" towards (or away from) the direction it is facing. Right now, it is just moving straight up or down rather than the direction the ship is rotated towards. I tried to use coodinate of bottom edge and top edge, but that didn't work. I tried to add detectors and add force to those but that did nothing. Argh, I seem to be missing something, something very simple, yet I can't figure it out.