You may be wondering, when driving along the open roads of Final Fantasy 15, how to transform your boring old car into the Regalia Type-F and fly around the world. The good news: It's easy to do. The bad news: You have to finish the game first.
Final Fantasy 15 doesn't make the process super clear, so here's a quick guide. To get the airship in Final Fantasy 15, you need to do two things:
First, take down all three Niflheim bases. Every time you wipe out one of the Empire's bases -- which you can accomplish either by sneaking around, blowing everyone up or a combination of the two -- you'll get a unique item. You need all three of these items to get the airship.
Playing through the main story will actually take you through two of these bases. The third, which I wound up beating after I'd finished the game, is located in Leide, just north of Hammerhead:
Once you've done this: 2) Talk to Cindy. And that's it. She'll upgrade you to the Regalia Type-F, and soon you'll be cruising around Lucis, watching Final Fantasy 15 go nuts trying to render all that terrain so quickly. (The framerate stays stable, but there's a lot of pop-in.)
The airship is mostly a novelty. Trying to fly off the map will just lead you to bounce off invisible walls. You can only land on roads, which can be a finicky process, and if you try to land elsewhere -- or fly into an obstacle -- you'll get to watch your entire party die in a flaming car wreck. (You'll get a Game Over, but it's fun to watch.)
There's also a secret dungeon -- one of the coolest things in the game -- that you can only get with the airship. More on that soon.