Stewart Paul, Riddell Chris. Stormchaser

Oxford ; New York : Random House Children’s Books, 2008. — 386 p.Sixteen-year-old Twig is eager to begin his new life as a sky pirate on board the famous Stormchaser. The crew's quest: to collect stormphrax—the precious, magical substance formed at the heart of a storm—in order to save the floating city of Sanctaphrax. Only a sky ship as powerful as the
Stormchaser, piloted by a man as fearless as Cloud Wolf, could risk entering such a storm...