How do ships sail into the wind?
A sail acts just like the wing on a airplane (when sailing towards the wind) in fact you could think of it as a vertical wing. Because of the sail shape (it’s a wing, remember) the air has to flow faster over the front surface than the rear. This causes a low pressure area at the front of the sail (lift) and the sail, mast and yacht, are sucked forward by this low pressure. In order to maintain the sail shape (which is the key) the wind MUST come from slightly to one side. So it’s not possible to sail directly into the wind. Modern sailboats (like the one I live on) can usually sail about 30 degrees off the wind, but it depends on sail shape, hull shape and a host of other variables. Some yachts can sail closer than that, some not so close. That’s basically how it’s done, though there’s a lot more going on as well. The wind causes the boat to heel (lean over onto it’s side) so sailboats have a deep and very heavy keel (about 50% of the yachts weight is in the keel) to keep the boat rea
