Springs can be thought of as "wheels" for the Battlefield 1942 game engine. They are what
actually produces the thrust for jeeps, tanks, and APCs, as well as allowing planes
to land and take off. Any dynamic, mobile object that needs to interact with the
landscape should have springs. Springs generate thrust by being children of an
Engine object, to make them roll, while others are simple passive and roll on their own.
This can be changed with the Grip property. Springs also must have a Geometry property with a proper
collision model to work correctly.