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Hello all.
I am currently making a handheld wind speed detector for a school project and I have been made aware that many keen boaters/sailors use these devices. I would be most grateful (and happy) if anyone who has or wants such a device could contact me with any information about these devices. Things such as why you need or want one, what the advantages of having one are and where to get one from would be handy.
Thanks.
 

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BiscuitBandit;
Wind speed meters or anemometers are used by boating people in order to determine what sails to use. As the wind speed increases the amount of sail area has to be reduced. Many racing boats have sails designed for limited wind velocitys, say 8-12mph. Many sailors can judge approximate wind speed by the feel of the wind or condition of waves but an anenometer is much more accurate
 

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Winds speed and direction indicators have a lot of uses in sailing but really come into their own for racing applications or for electronic navigation. This is especially true when tied into other instruments such as a knotmeter, electronic compass and an autopilot.

The bad news is that electronic wind instruments are terribly inaccurate in an absolute sense. Air density varies with temperature and since most wind instuments operate on impact (Newton''s theory) rather than due to aerodynamics (like an airplane wing) the readings of a wind instrument calibrated in summer can be very inaccurate in colder weather. But racers generally are only looking for relative information (as in is there more wind and more speed than their was a moment ago) and so wind instuments work fine for most racing applications.

On racing sailboats the sail trimmers and helmsman need information to fine tune thier performance. If you are tring to agdjust course and sail trim for maximum speed and you only had a knotmeter to tell how fast the boat is moving you could not tell if a speed change was because of something you were doing differently or whether the wind had changed. After a while, you learn what the ''numbers'' should be for a given boat and can quickly look and tell if your boatspeed is consistent with the windspeed.

Tied to a knotmeter, more sophisticated wind instuments can tell you true wind speed and true wind direction and tied to an electronic compass it can give you Velocity made good (the speed at which you are actually moving upwind or down) so you can find the best course to the upwind or downwind mark.

For cruisers, Autopilots can use a combination of true wind speed, true wind direction and information from an electronic compass on the boat''s compass course to allow an electronic autopilot to keep a boat on course relative to the wind.

Good luck with your project,
Jeff
 

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I wont repeat what the others have already said but there are some sites where u can find out about the wind speed devices, www.flytec.com is one site that sells such devices and it gives you details about the products. There is an article on this site where Tom Wood reviews one particular device but i cant find the article anymore, but u might be better at finding it than me
Good luck and i hope this helps
 
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