Vehicles

Propultion Methods

All rubber band engines all work by providing an initial kick to give some good starting momentum, and then relying on that for the rest of the journey.

• The Stretch
  This is one of the most common ones for turning an axle quick to generate momentum. The elastic band is attached to a point some distance from the axle you wish to power. The rubber band is the stretched to the axle and wrapped round. Then the axle is wound backwards till the rubber band has no stretch left. When you release the rubber band bounces back spinning the axle.
  
• The Twist
  This one is most common for planes or boats, devices that uses propellers. The rubber band is attached to a fixed point on the body of the vehicle and onto the shaft of the propeller (parallel not perpendicular to it). Then you wind the propeller in the opposite direction you want it to go. Then you wind and wind and wind, until you can't wind any more. When you let the propeller go it spins very quickly back spinning the propeller.
  
• The Sling Shot, This is basically shooting the vehicle with the rubber band. This works great for little gliders.

Cars

For cars, the stretch method works best. They car be pretty much made from anything and look like anything you want. One key feature is that the wheels that are being driven by the rubber band are usually larger and heavier than normal so that they can hold more momentum.

Planes

For planes, the twist or sling shot works best. The twist for propellers and the sling shot for darts or gliders.

Boats

For boats the stretch or twist method works best.