Thursday, January 19, 2012

How are boats using sails able to return to their starting place?

All those boats using a sail and traveling upwind, like the old time galleys using a sail, once they reach their destination how are they able to return to where they came from?How are boats using sails able to return to their starting place?
It's called "tacking."



It would be easier to explain to you if I could draw a picture. Think of the sail as an air foil. When the wind blows straight from the boat, (front,) the sail will luff, (flap.) However, if you turn slightly to one side or the other the sail will fill with air and start moving forward. The best point of sail is what's called a "close reach" or "close haul." That is when the wind is 30-60 degrees off the bow of the boat blowing toward you. You actually go faster trimmed, (set up,) this way than if you were "running" which is with the wind directly at your back.



Understanding this, you maneuver the boat in a zig-zag manner, (tacking,) into the wind. There's whats called a "beam reach," which is with the wind at 90 degrees off port, (left,) or starboard, (right,) and "broad reach" where you have either a right of left quartering tailwind.



Here is an excellent site that will explain it in much more detail. http://www.sailingusa.info/sail_trim.htm



You should try sailing sometime. For my money sailing beats out speed boating any day, except of course on those days that there is no wind. Then you just motor out and take a swim.
1. they have outboard motors.

2. they're using tugboats.How are boats using sails able to return to their starting place?
tacking. If if a boat had to go in a straight line exactly with the wind, nobody would ever get anywhere they wanted, they would have to wait until the wind changed, and it often doesn't on oceans and so forth. However, most sailing is done at angles to the wind, and you can go just a few points off of straight upwind with proper trimming. In order to go upwind, you tack- that is, zigzag upwind. you can't go straight, but you can go against the wind at a pretty steep angle.
They don't travel up wind they travel across the wind it called tacking.Old time galleons,sail down wind. followed the trade winds that travel south to north in a circle west to east to south.I sailed for years threw the carribean. Know i have a Sportfish 48' I have spent enough time zig zaging.How are boats using sails able to return to their starting place?
Above give you the concept.

If, you would like to play and see how it works, go here;

http://www.nationalgeographic.com/volvoo鈥?/a>

It National Geographic and it a simple sailing program. You can get the feel of Running with the wind and Reaching for the wind. Well, that how I say it. ;-)

You have a Sail Control and a Rudder Control. Arrows show the direction of your wind. You can see information below like your speed. As I say, it a simple simulator to see how the boat reacts to the wind, sail position and rudder.
Downwind is going with the wind. To go against the wind they tack. Most boats can tack within 50 degrees of the wind and go back and forth across the wind making headway up wind. They also studied currents to know when to go where.

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