How do ships sail into the wind?

Question

I was watching the history channel and the statement was made that "like modern sailing yachts, Chinese junks were capable of sailing into the wind." Can someone explain to a lay person how a sailing ship can be propelled by wind INTO the wind? Or am I just misunderstanding the concept?

Answer 1

aarrgh  mate  !!!   we   dont  sail  into  the  wind........   we use that   big   diesel

Answer 2

I dont know sorry!

Answer 3

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 reasonably upright (the sails work better the more upright the yacht is). Also, modern keels have a wing shape so that they generate lift in the water (on the windward side) this reduces the tendency of the yacht to be blown sideways (we call it leeway).

Hope that helps some?

Answer 4

The two answers above are more or less correct.  To put things in a simple way for most people to understand: A sailboat can only sail about 45 degrees into the wind.  That would be 45 true wind.  As a boat (or anything) moves, it creates its own wind.  This wind is called "Apparent Wind", for the most part, a sailboat can sail about 30 - 35 degrees into the apparent wind.

Answer 5

Hi, to further answer your question, the hull design also comes into play. Sailboats are designed so that when they are being propelled forward by the wind, the hull creates a disturbance in the water, and as the wake leaves the aft parts of the boat, it creates a vortex of sorts, and also helps push the boat through the water. The previous answers are pretty much right on the mark, my experience is that about 30 degrees into the wind is acheviable, although you are probably pounding and not making as much speed as if you headed off a few degrees. I agree with the salty captain...use the diesel when heading north. That's what fuel curves are for.

Answer 6

maybe they had oars? lol

Answer 7

The short answer is through orientation of the sails to catch wind that will cause motion.  A longer answer is:

Two thousand years ago, triangular sails appeared. With proper orientation, these sails could convert wind power from any direction into forward thrust. The sail might be pushed or pulled by the wind force, and the pull was stronger than the push. Although there was no physical understanding of the pulling force, it allowed the boat to sail into the wind. In the 18th century, the pulling force was identified as LIFT, and it was discovered that it was generated by fluid flow over a curved surface, called an airfoil.

Answer 8

Modern day sailing vessels can sail 25 degs off the wind galf rig junks sail down wind or broad reach which is on the side of the vessel no sailing vessel can sail directly into the wind the close to the wind the slower you go>with out Aux power>

35 yrs sailing know 48 sport fish >

Answer 9

Sailing ships don't sail directly into the wind. When sailing into the wind, they perform a maneuver called "tacking", or switching back and forth so the wind comes at the boat at an angle instead of straight on. They sail at an angle to the headwind so the wind is coming at the boat from either the starboard or port side of the bow. This allows the sails to catch the wind and propel the boat forward. They alternate direction so that overall they are traveling the direction they want, but are doing it in a zig-zag motion. Here's a better explanation, because it comes with a cute little picture.

http://en.wikipedia.org/wiki/Tack_(saili...

Answer 10

Sailboats can sail upwind to an extent. The tack closest the wind is a called a "beat." And the more efficient the boat the closer the wind. For most sailboats that is no more than 45 degrees.