Wind speed and sail size

[JeffGerke]

What wind speeds would a 6.5 typically be used with? How about a 7.5? These are the two sail sized I plan to start with. I weigh about 170 lbs if that makes much difference. When looking at the wind meters I'm not sure if what I'm looking at is good or bad. For instance this morning it looked like Grantsville was in the upper teens. What sail size would have been good in those conditions?

[Craig Goudie]

How much you weigh and what board (and skeg) you have also makes
a difference, but Rick H was at Grants this morning on a 7 meter sail,
and he's about your size. Note also, that wind velocity measured as
particle velocity will have less punch at higher altitudes. If you measure
your wind with a hotwire anemometer, you'd find that a 20 MPH
wind at 5000 ft is very similar to a 15 MPH wind at sea level.
So, if you measure with a force style meter (like a venturi tube)
you'll always know what to rig. If you measure with a spinning
anemometer, it will depend on how much loss you have in bearing
friction. As the friction approaches zero, you'd be close to particle
velocity wind speed, and have to accommodate for altitude.

Now that I've said all that, I weigh 180lbs. I would use the following
sails in and around the Northern Utah area in the following winds:

9.5 9-14MPH
8.5 11-15MPH
7.5 13-17MPH
6.5 15-20MPH
5.5 20-25MPH
4.7 25-30MPH
4.2 30-35MPH
3.7 35-40MPH
3.2 40-45MPH

Yup, those big sails are highly redundant. I don't really own
a 7.5, and my current plans are to drop from the 9.5 to the 6.5.
We'll see how that works. Remember also that Force is a squared
relationship to velocity i.e. if your wind velocity doubles, your wind force
goes up 4 times.

Does this help?

-Craig

What wind speeds would a 6.5 typically be used with? How about a 7.5? These are the two sail sized I plan to start with. I weigh about 170 lbs if that makes much difference. When looking at the wind meters I'm not sure if what I'm looking at is good or bad. For instance this morning it looked like Grantsville was in the upper teens. What sail size would have been good in those conditions?

[JeffGerke]

Thanks, that helps a lot. It is interesting to see how redundant those big sails are. Maybe I should rethink my stratagy. I just bought a 7.5, maybe my next sail down should be a 6.0 instead of a 6.5. What are some good force style meters to buy? I imagine they are expensive.

[Craig Goudie]

Actually the force style meters are the very cheapest, usually
just a plastic tube with a red ball inside. If I already had a 7.5
I'd drop to 6.0, but, there's a lot more 6.5 wind in Utah than 6.0 wind.
In fact, there's a lot more 8.5 wind in Utah than 6.0.

-Craig

Thanks, that helps a lot. It is interesting to see how redundant those big sails are. Maybe I should rethink my stratagy. I just bought a 7.5, maybe my next sail down should be a 6.0 instead of a 6.5. What are some good force style meters to buy? I imagine they are expensive.

[Josh Shirley]

A couple of editions ago, Windsurf mag, had an article about this. I think it was titled "In the Numbers" or something like that.

Anyway they put out some surveys last year and found that the most commonly used sail among there readers is 6.0. So I would say the most important and best sail you should own is 6.0 to 6.5. If you are going to put some money into this, buy the newest possible edition of that sail. Then spend less money on a big sail like the 7.5 or 8.0.

Also if you get a newer sail in those two sizes they will be able to adjust to conditions much better then older models. Newer 8.0's can be sailed pretty comfortably in high wind conditions, old ones will stretch your arms, break the nose of your boards, and rip real easy. The newer designs have wide wind ranges. Older ones don't. That is why people would buy a 5.5, 6.0, 6.5, 7.0, 7.5, 8.0 and a 8.5. That is crazy and takes up to much space. Newer sails have so much adjustment to them that you can make a 6.3 sail like a 6.7 and 5.3. You can also get the newer 8.0s to feel like a 6.5 (except for weight.)

Many classifieds and stores have good deals on last years models, so look around. A used crapy sail is better then no sail, but don't be cheap get a decent sail that will last and keep you happy. There is nothing better then having equipment that lets you sail how you want to sail. I went through 4 sails of various sizes, trying to figure out how to rig and sail them. Then I wised up and purchases some new sails; which have helped me improve leaps and bounds.

[ammisco]

Good deal at water-play for a Windmeter

http://www.water-play.com/2003Site/WS-a ... eter.shtml

Never used one but it is the most affordable one I've seen.

-A

[Rick McClain]

So it appears to me that, according to Craigs chart, all most of us need for typical "Utah" summer wind is a 20 Meter sail and a great big fin.