First, the extrapolation of the fire magic engines from PC2 as a recreation of the elemental binding techniques, then updated as the old techniques are rediscovered through old tomes and recovered technology. The props become the supports for the elemental ring, but is smaller because the gnomes are cheating using wings for lift.
Second, either the continued development on the base technique of elemental binding to capital ships, in this case a supercarrier starship, or a prior civilizations sufficiently advanced technology. Or both because I do what I want.
And finally, a warforged/robot/whatever with an elemental ring because it can transform into an elemental airship. Spawned by this tumblr post.