Last Exile is set in a far distent future where a group known as "The Guild" controlls everyting including who has what technology.
It seems quite a long time ago there was a war and the guild won and absolute dictatorship over technology and the rules of warfare is what they got.
Ships are driven by a claudia unit. Some sort of anti gravity technology. The guild retains a tight control over that technology and if they don't like what a ship is doing they can "recall" the claudia unit causing the ship to fall.
However not all ships rely on guild supplied technology. Van ships use a simple claudia unit and aren't regisared with the guild. As such the guild can't recall the units on thies ships.
Van ships look like a fusion between star wars speader bikes and the modle t ford.
The story focuses on two van ship pilots who work as the equilvilant of the pony express. Delivering messages and pacages they are paid by the danger rating and a ship known as the safest place in the world beecouse the capten managed to create his own claudia unit instead of getting one from thee guild and as such dosen't answer to anybody.