Okay, so I've started to toy around with ground troops, and I'm not sure what to do with Drop module. They're used to board ships that I know, but are they used to land quickly on a planet? Put otherwise, do I need a dropship to efficiently invade a planet? What would happen if I were to unload troops on an hostile planet?
Also, is it possible to transfer troop in flight, so that I can have a large, civilian troop transport and a small, fast dropship to board ships?