Ratchet's ship was a homemade design that Ratchet built on his homeplanet Veldin from pieces of scrap. Without the use of a robotic ignition system, however, the ship remained immobile.
When Clank crash-landed in Kyzil Plateau, Ratchet finally got his ship to take off. He promptly crash-landed on planet Novalis, however, and was forced to find a new ship.
According to concept art unlockable in the first game, Ratchet's ship was supposed to be a "real homemade job held together by gum and rubber bands." According to the concept art's description, it is not clear why Ratchet crash-landed the ship so early on in the game.