my awesome crew wants to have an explaination of apparent wind, can wind speed(apparent wind) be enhanced on any sail boat perpendicular to the true wind?
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<br>thank you Tinab.<br><br>

Without the explanation, Yes.<br><br>

Apparent wind is simply the wind induced by the forward speed of the boat. If you go for a drive in your car and there is no wind and you are going 30 mph, you can stick your hand out the window and feel 30 mph of apparent wind. The true wind vector must be added to the opposite of the forward speed of the boat. Thus for a given true wind speed, the faster the boat is going the closer the apparent wind angle moves toward the front of the boat. With no sail adjustment, cats need to bear off slightly in puffs at account for the change in apparent wind angle because they are moving faster. A simple example is a cat is sailing at 90 deg to the 10 kt true wind at 10 kts. The wind the crew feels on the boat is 14 kts 45 deg from the nose. Try to sketch it out on a piece of paper, it is 100% geometry. Hope this helps!
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Lets make it simple and avoid math:
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<br>You create wind in relation to yourself when you move, and it can be felt in your face. The faster you move, the faster the wind in your face.
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<br>If there is also a natural wind blowing, as in a cat, both winds are added, creating what is called "apparent wind"
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<br>As it would be expected, the apparent wind is different in direction and strength from both the natural wind and the created wind.
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<br>The apparent wind blows from a direction between the direction of them both, but closer to the fastest (the greater the difference, the closer to the faster wind direction).
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<br>It has a strength which is slightly less then the sum of both winds, and the closer they blow in dierection, the closer the wind strength is to the summ.
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<br>You can perceive this easily going upwind and downwind in sequence. Upwind the wind "feels" strong and straight downwind it feels weak.
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<br>I hope it helps,
<br><br><br>Luiz

Go to the webpage at
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<br> http://www.geocities.com/kustzeilen/sailvectors.html
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<br>Scroll down a bit till you'll see the three drawings with alot of arrows. The black vertical arrow in each drawing is the wind the other black arrow is the airflow caused by the forward movement of the craft and the resulting blue arrow is the apparent wind.
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<br>Hope this visualizes things and thus help your understanding
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<br>Wouter
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very much thank you , this helped me alot !!!!! <br><br>

Um... are you by any chance asking if apparant wind is ever as much as 90 degrees away from the true wind?
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<br>Hey Wout, how far forward does the formula pull the apparant wind when going like, 135 degrees off the true wind? Does it come a full 90 deg. forward to 45 deg (apparant) off the bow?
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If I understand you question right thanI say :"yes, this happens when the boat is travelling on 135 degree to true wind at a velocity of 1,41 times the true wind speed. This is quite a bit and rarely encounteredon a catamaran. Only the true lightweight big rigs will get there for on this course the boats need to overcome a trust dip first. Maybe genaker boats are more able to achieve these speeds. Test series must still be held to proof this.
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<br>Actually the situation your describing is the exactly last arrow scheme of the third arrow drawing.
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<br>Go to
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<br> http://www.geocities.com/kustzeilen/sailvectors.html
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<br>to see it, I'm talking about the third picture when you scroll down.
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<br>Wouter<br><br>