The arm of the paper plane flinger fires the paper plane into the air. It is powered by two motors and fires the paper plane over the NXT brick on to the moving belt.
The NXT brick and touch sensor are used for making sure the arm works properly also the touch sensor is used to activate the arm as you will see in the program.
The moving belt delivers the paper plane to the person at the end. It is there so it can give the paper plane an extra boost if needed.