For the most part many of these ships have a nominal top and bottom. It always bothered me when I watched Star Wars or Star Trek that when ships approached each other they both always had the "top" of the ship oriented in the same way as the other ship(s) in the area. Up and down have no meaning in space so why would they miraculously be oriented the same way in the void of space.
The Millenium Falcon had no problem debunking this. Also, couldn't it just be the camera angle? :smile: