alt Hacker News>the Earth is flat and you stand at 0 N 0 E, how do you move in a straight line East of there?
This is something that was more or less solved a long time ago with surveying instruments. You don't have to move in a straight line, you build triangles out of sight lines.
I can kinda see how that would work, but it presents the challenge that whatever route you plan, it cannot go over water for more than a few kilometers.