How do sailboats sail?

Answer 1

With a square rigged sail, the wind simply pushes the boat along.

With a fore and aft rigged sail, the wind is caught at an angle and slices on past the sail, pushing the sail hard down wind and a bit forward. A deep keel on the bottom of the sail boat tries to stop the downwind drift and, as a result of a bit of a push forward on the sail, the sail boat manages to scoot across the wind a bit.

Square rigged ship:

http://sailing-ships.oktett.net/golden-state.jpg

The wind just blows the boat down wind.

Fore and aft rigged sailboat (a sloop)

http://2.bp.blogspot.com/_98ZiJEAKrlI/Rql8iSS1u5I/AAAAAAAAFc4/hwyku_OY29E/s400/9%2Bsm%2Bsb%2Bpassing.jpg

Note that the sail boat is tipped over a bit (heeling). This is due to the wind trying to push the sail boat down wind and the bottom of the sail boat (the keel) trying to stop the drift down wind. The wind is slicing off the sails and pushes the sail boat a head a bit.