The Last Exile - Complete Series
Longtime friends Claus Valca and Lavie Head make a living as couriers, flying an airship left to Claus by his father. The 15-year-olds spend their time dreaming of flying their ship across the dangerous, stormy area of space called the Grand Stream until one day they agree to take on a little girl named Alvis Hamilton as "cargo," letting her ride as a passenger to her destination; the air-battleship called the Silvana. The job turns out to be more than the two bargained for as they become entangled in the war that's been raging between the two countries on their world for years.