Light Wind Machine

[Wetstuff]

windm: It is nice to see you pressing the edges of design. The history of any design project is usually restricted by gains at one end = losses at the other. I do not think it crazy to throw away the top end and claim one band of the wind spectrum. It seems everyone feels the need to claim 'all things for all people'. This is an already small market, you'll probably never be a major player (coming so late to the game) .. so why not become a hero to some rather than an afterthought to most. Good luck.

Jim

... this is what I call light air: http://wetstuff.com/movie/R16_strut.mov

[windm]

Hi I send a schema of this kite ...for understand better how works is really adjusted the size of ribs and front tube for have the best performance ...not drag and light as are posible......

[FredBGG]

That's a nice looking kite.
Must have been pretty difficult to make a kite that large with such precision.

Have you considered adding a bottom skin to the kite... a bit like the wide mast sleeves of windsurfer sails.

It would clean up the airflow under the leading edge.

I think you could add this with some super light fabric and make it open cell with a wider openning at the front and a smaller openning at the back for water drainage.

If you are aiming to make a race kite this could be the way to go.

As far as you wind meter reading in the second part of the video I may be wrong, but
when the wind is onshore I have found that it nearly always reads a few miles lower over the sand
especially in the sun. I have always found that there is more wind just a bit furthur out.

While doing your tests try to get a reading from a boat and then most of all
fly your kite low to try to test the kite nearer where the wind reading was taken.
If the kite does not have more power low it means that there is more wind high up.
When you fly a kite low it is more in the powerzone.

I'm not saying this to discredit your test in anyway.

Also another thing you can do is put a meter on your lines and park the kite
high and take a reading for a few minutes and than see what the average is.

Another very good reference is to have a control kite.
By that I mean fly or try to fly a "know" kite for direct comparison.
Testing against (or should I say beside) a flysurfer speed 2 would be a good reference.
It is the state of the art low wind kite.
There are also flying wind meters that use a small kite and measure the tension on the lines
to measure wind higher up.

Keep up the good work.

[BWD]

Looks very cool. Makes me wish I liked sewing better.....
(Just patching up sails and kites is enough for me...)

Re: low wind range, for any novices reading this one, just keep in mind:

windgradient.gif (106.96 KiB) Viewed 1625 times

So 7-8 knots in the hand, means 10-12 knots where the kite flies....
Just saying that for anyone who doesn't know, hand held meters don't give the same wind your kite sees.
Weather installations usually have the meter at 5-15 meters - a better check on the right kite size.

Claiming "8knots" on the beach is helpful for showing people they can ride when their hand held meter shows it, I guess, but it is confusing. True 8 knots is specialist territory, and impossible or boring for most of us 75-80kg+ folks...

Sorry if OT a little, but looking at the graph, you see both why there are so many claims of "kiting in 8 knots," and also why there are bad problems if you use the wrong kite at the top of the range. For example, too much kite in "20kts" at the surface is often not a big problem, even when you're talking about a 13-16m kite, but too much kite in "30" at the surface is a big problem, even though you are talking about only a 9m kite. But y'all all know that I guess, so...

Back to the design, I like that it's not too cone-shaped, a little more open TE always just seems better to me than some other shapes

PS - and I should say thanks to p frank for originally posting the graph a while back...

[diraklib]

Excellent post BWD. I kinda thought that, but it really sinks in when you see the graph.

thanks,
db

[tukyank]

10-15 kts is not light wind.....to me. Sad, but true.
Many, many, many kites can have a 200lb rider going in this wind range - its the sub 10 kts range where the challenge is.

What's my point? Lets be a little more carefull when we throw the term "light wind machine" out there.

[windm]

BWD ...thanks for your post is really interesting.....but tell me one thing:

When you arrive to the beach in really light wind conditions and seen the water .....and you want know what wind is ....how do you do ? take the Anemometer and jump antil 25 m hight to see the real wind? Or read the Anemometer.....

The technology exists and all the people when go to the beach and use a an Anemometer ....read it and have a average wind to know it .....please dont explain me tales about the diference gradient the people want know if when go to the beach and read 10 knts in the anemometre can go or not no more............

The fact.....some Cab 17m contra and 16 waroos ....and more on beach ....we planing and go up the wind ...the people try to ride with the Cab 17 and his staff.....and return walking .....

Not one time a lot of times ......fact ....now the people see this kite in our spot and NOT TRY to ride with any kite.....(sorry ....not all the truth just one try to..... and go well FS SILVER ARROW .....but 4 sq meter bigger).....



For my friend tukyank .....please before speak about something know about what are speaking I recomended to see the vid first ....thanks.....

[OzBungy]

...

When you arrive to the beach in really light wind conditions and seen the water .....and you want know what wind is ....how do you do ? take the Anemometer and jump antil 25 m hight to see the real wind? Or read the Anemometer.....

....

I stand on the cliff top and look at the water surface out to sea and listen to the wind noise. At the same time I check two weather stations in the area on my phone (one usually reads high and the other low so I split the difference) and look at the tree tops.

I then go out down to the beach and listen to the wind noise. If at least two indicators suggest there is wind I'll go kiting. 9 times out of 10 be riding and doing the odd jump.

Frequently people will try to join me and not be able to get off the beach. I am pretty skilled at trimming the kite and board and I have a specially made light wind TT. Local knowledge of wind conditions helps.

I have tried to help people to learn how to ride in light conditions but most don't want to listen. The rider makes the most difference followed by the board then the kite. I weigh 80kg and my mate weighs 95 and we can both do well in light winds.

I never use an anemometer, although I own a few. I can usually find somewhere to stand and a way of holding it so that it will confirm whatever I want it to say.

[schmoe]

Come on guys give the man a break. When we say 20 knots, we mean 20 knot that we feel. If we held an anemometer this is what we expect to see. Not 20 meters above ground. No one is giving wind ranges for kites at 20M above ground.

If someone need to extrapolate how much the wind is up there, he can use a table like the above. When we say a kite can sail at 8 knots, we mean 8 knots at eye level. Now if this is on shore or on the water, it’s a different story. But in terms of height, eye level.

Windm what is the secret? From the pictures it looks like any other kite. An efficient profile? More efficient than the speeds?

[Gigi;)]

Hi,

@fred - bigger kites are actually easier to build... also the sewing errors are more "compensated".

While we're at it, I've recently been kiting 90% - 95% sessions with my new 8m 3struts ILE kite... in landikitng (grass) in everything above 7,8kts.



On water, 65kg rider can go easily with it in 10kts with skim... Good low wind performance is not get only by reduced weight but also by many other factors.