So let's put all of the pieces together to understand the illusion:
- When you see the Batmobile careening through city streets, that is one of the four "race" versions of the Batmobile. They have real engines and drive trains, but the interior is a stripped-out permutation of a NASCAR race car.
- When you see the Batmobile fire its jet engine, that is the special "jet version" of the car. There are six extra propane tanks hidden inside the car to fuel the jet.
- When you see the Batmobile flying through the air, that is usually the 1:5 scale miniature version, intercut with shots of the "flap version" of the full-sized car.
- When you see Batman get in and out of the car, that is the "opening" version of the Batmobile. It has a more realistic interior and a separate driver hidden inside the vehicle.
- When you see Batman inside the cockpit, that is a static set.
So here's an example of what happens when, in the film, Batman drives home to the Batcave after a long day of crime fighting:
- The race version drives down the road.
- The jet version fires its jet engine.
- The miniature version flies across the ravine.
- One of the full-sized race versions enters the Batcave, flying through an actual, full-size waterfall. This shot is incredibly complex. They turn on the water for the waterfall. The car drives down a road and shoots off the end of a ramp to get itself airborne. The car travels through the waterfall, where the downdraft and weight of the falling water has to be taken into account to get the angles right. The 5,000-pound car flies 30 feet and lands with an incredible thud on a reinforced-concrete landing pad. Then there is a sand berm to help slow the car down. There is also a huge arresting cable to stop the car in case something goes wrong.
- The view switches to the static cockpit set to show Batman's perspective.
- The view switches to the "opening version" of the car, which pulls up in the Batcave set, stops and unfolds so Batman can get out.
All of those different, real, physical versions of the car come together in the movie to create the illusion of the Batmobile.
As Nathan points out, understanding this process gives you an appreciation for why a modern film can cost so much to make. The Batmobile itself is eight different versions of the same car, built and managed by several teams containing dozens of people. The "Batmobile" cost many millions of dollars in research, development and fabrication.
For more information on the Batmobile, "Batman Begins" and related topics, check out the links on the next page.