Tutorial 2: Learn how wind propels your boat

In this lesson, all the gates are lined up so that we can forget about the steering. Steering is disabled and you can focus on the main subject - the wind. Some parts of this tutorial are meant for your own experiments. Try different sail orientations and compare the effects. Click "Done" when finished. This tutorial consists of the following steps:
  • The wind is blowing from behind and it is pushing your boat forward. Note the Sail icon on the right. It is near the top. What happens when you drag it to the bottom?
  • By moving the slider down, you pull the rope attached to the sail. In the downwind situation, this decreases your speed because less wind is caught by the sail. Let the sail out again (drag the slider up).
  • Now see what happens when the wind direction changes...
  • The wind is blowing from the left. As you can see, the sail fully out is no longer the best configuration - the wind slides off the sail and barely pushes your boat. What can the sailor do?
    • By pulling the sail in, you change its orientation so it receives more of the wind force. Is it the more the better? Try pulling the sail fully in...
    • The sail is in too tight - much of the wind force is wasted on tilting the boat and your speed suffers. With strong wind you could even capsize!
    • The sail is close to the optimum orientation - and the boat reaches the maximum speed.
    • The sail is too far out - it only catches a small fraction of wind energy.
  • Now press the rope and drag left.
  • This special gesture locks the rope so you don't have to keep your finger on screen all the time. Now unlock the rope by tapping it.
  • Congratulations - you learned how wind power works!