Tides of War

Is it possible to place my craft on the seven seas using the logitude and latitude markings in the game? I've never quite understood the process in computing yr location via these settings. Particularly the idea of 'minutes,' time in discerning place on the globe! Besides being a math incompetent, I am totally befuddled in navagating the high seas in this manner! Is there anyone who can explain it in a ten year old's terms?

As I recall you can steer/plot a course using the X/Y cords on the tac screen, I don't think they are real-life accurate.