Is there any way to find out the true surface area of a kite EDITED 'from the manufacturer or from other sources'? Is this info available on requests, or through distributors of the brand?
As most of the design is done on computers, the manufacturers must have the exact figure. Then we would have true comparison between similar kites of the various brands, and we could build a quiver with a mixture of brands if we like.
It's frustrating to see a kite advertised as an 8m, when it's surface area is hardly bigger then 7. It is actually called misleading or outright cheating, unless they specify somewhere the correct figure.
For the flat surface area, simply divide the canopy into a series of regular rectangles.
Pick a number (10-20-30-40cm) then measure the depth of the canopy from tip to tail at each interval.
Multiply the depth by the width to get the area. Add all the areas together and you have the flat area of the canopy.
You have to measure on the same side of the rectangle and you have to measure across the full width (you can't just measure half and double it). That's because as you measure from tip to middle your measurement is a little high because of the curve of the le. It self-corrects as you measure down he other side from middle to tip because that measurement will be a little low. (alternately you can measure in the middle of the rectangle and get a self-correct measure for each rectangle).
You can estimate projected area by working out the ratio of the projected span to the flat span (just pump up the kite and measure the distance from tip to tip) and factor down the width measurement of each rectangle.
Stressing about the area is a bit pointless. You also need to know the aspect ratio and the profile depth to know anything useful. Even then you won't be able to tell what a kite is like until you try the kite in the conditions you intend to use it.
Similarly, having a mongrel collection of kites is not a great idea. It's far better to find a brand you like and stick to a quiver of matching kites. Everything works together and the feel is relatively consistent and you can get support from the shop.
^^^ good info, and good little homework when demoing kites. 
But what happens to those who have no luxury of demoing.
I edited my post now, as I was wondering about a way to get this information from the manufacturer or other sources.
Or if you wanted to be more accurate do the same thing using the measurements to calculate the area of a trapezoid h+(l1+l2)/2 and add them all up (h is your preselected interval).
No idea on getting the info off the manufacturer, I know there are a couple of brands around that have senior team members that post on forums but not sure about the rest. Bill Hansen for example has posted some of these details on the kites he designs for Switch on Seabreeze and on Kiteforum. I'm sure it's not really giving much away for the manufacturers to give out this info (though I've seen a few kites that look damn big for their published size and owned one that was damned small) so an email might do it for you.
But what happens to those who have no luxury of demoing.
I just want to know if there is a source where we can find the exact size of a kite. I can't be any clearer that this.
There are many factors effecting the performance of a kite apart from the size.... we all know that, nothing new. Size does matter a lot,though, and it is certainly a decisive factor for everyone when choosing a quiver especially of mixed brands.
In my post I was referring to differences of 1m, not 0.1m. if you followed the discussions on the gear review lately, you may find some examples.
BTW, RPM, honesty about the size of a kite is it too much to ask from a manufacturer? Are you a guy who just take it....
Don't know where you've been buying your kites, but mine always come with there size printed on the wing tip. Next time your at the beach have a look at the other kites in the air, some will have 9 others 10 etc printed on them, this of coarse is their kite size.
Select to expand quoteThe number printed on the wing has always been the right number for the kite that I was flying. Never had a misprint on my kites before?
I have riden the same brand kite for a number of years. For our local conditions I have always been on a 13m but in recent years I have been on an 11m for the same sort of wind strength. Lay the kites over each other and the newer 11m are very similar in surface area to the old 13m.
Wasting ya time, why need to know actual surface area? Design and bridle set up make a huge difference. Just fly the damn things and see what works in your normal wind range.
It's all about the projected/effective surface area, not the flat surface area when you lay it out on the ground. That's why a few years ago you used to see guys riding C kites a size larger than the guys riding bow kites, because the bridle used to pull the kite into a flatter shape. And why foils/doonas are smaller still.
These days it seems most inflatable kites use the area sizing convention, but in reality it's a wind range sizing for a 75kg person ie. a 12m typically works "best" on a twin tip in (approximately) 15 - 23 knots, 10.5m 18-26, 9m 22 - 30 etc etc. Of course, there are some variations between.
Yesterday I saw a Best Kahoona at Brighton Beach (Melb) that didn't have a surface area size on it - It just said "Medium". Maybe that's "The Future"
My local kite salesman says;
"The 10 now has as much grunt as a 12".
"The 12 now turns as fast as a 10".
Does that mean the 10 is really a 12 and the 12 is really a 10?
The surface area does matter a lot when comparing similar shape kites. It makes a lot of sense to compare the surface area of Delta to Delta, C to C, etc kites of the same size and expect them more or less the same. For example if I am replacing my 9m (surface area) Delta kite, then I want my new 9m Delta to be 9m, not smaller or larger.
Differences in the bridals usually have limited impact in the power. Changes in the bridal may change the feel, responsiveness, and maneuverability of the kite. The shape and the projected area will determine the overall power.
The windrange (given by the manufacturer) is not at all indicative. The real windrange of the kite depends largely on individual factors, which the manufacturer cannot take into account. Obviously all manufacturers would want to prove their product.
There are two reasons why a manufacturer may and does give misleading info about the size of a kite....
1. To prove their kite turns faster then the same size of the competitor: number will be bigger.
2. Prove their kite is more powerful then the same size of the competitor: number will be larger.
That's why so many of us have noticed, that there is a problem with kite sizing. If anyone still wants to keep the head in the sand, I have no problem about this. I was hoping (and still am), that some of the distributors or manufacturers have a say about this.
I wasnt happy with the turning speed of my 10 so I changed the number on the side to 12. For a twelve it now turns ok. Also the bottom end has improved considerably. I now find myself riding my 10 in conditions that previously I would have had to use my 12.
I wouldnt have thought such a small change could have such a profound impact on my kite.
yeah projected area used to be the thing and in makes sense. but its not used much these days. Same goes for aspect ratio.
These days i don't care much about the number on the side of the kite. just what its sweet spot is. thats what i look for. A kite to suit X wind speed.
I don't think you can easily compare size for size against brands as the differences can be too big.
Andrash,
you want the same supplier who apparently enhanced his kites performance by printing a different number on it, to give you the real measurement? And you expect the number to be different to his initial claim? Good luck with that
A kite which suits X windspeed for you may suit Y windspeed for someone else, depending on a dozen of individual factors, so if you go with the manufacturers' recommendation... well good luck.
Comparing surface area of similar style / shape kites is not difficult at all. Just spread 2 of them over each other. If one of them is about 1 or 2m smaller than the other, it's an easy bet which one will deliver more power. Minor differences in the shape or different bridal will not make a huge difference in this.
... expecting the manufacturer to admit that the true size is significantly different from what's written on the wing, yea.. I know, waste of time... that's about honesty..
Next time when I buy a 3 liter V6 which turns out to be a 2 liter V4... I will say "Oh well, but it has larger wheels and painted red, so it should be the same"
Thanks for all responses
Good luck in your quest to find the truth in kite sizes! I'll just be out kiting, just ask if you need my help with anything.
It makes more difference where the cloth is located ie at the back of the kite or wingtips angle of attack bridle etc ..I have a 7m which I ride from 15kn and 5.5m for 18kn + so knowing increments within a metre aint going to be a deal breaker. Kites differ to much..sorry if this doesnt wet you nerd appetite.
Gee it's a tough audience Andrash.
Completely reasonable request that, as you've mentioned, kite companies ignore for marketing reasons.
Interesting that some kites like Best and AndreC's Fone give sizes to 0.5 m - indicating at least some attempt at accurate sizing and acknowledgement of the question you ask.
Personally I find it annoying when companies use marketing strategies that intentionally mislead the consumer.
The number printed on the wing tip should always be view with suspicion even if it is accurate. These days we have big boosting kites, freestyle kites, wave kites etc, all with their own characteristics - bottom end, top end, drift, boost...........Square meterage is only a rough guide. Try before you buy in a variety of wind strengths.
My Ozone Reo 10m doesn't have the bottom end that my Ozone Catalyst had and neither of them have the low end grunt of my mate's Switchblade 10m, but in the surf give me the Reo any day.
For a more accurate comparison you would probably be better off weighing them. Cant be much difference if any in the fabric. Probably most manufacturers are getting it from the same factories. Beats dicking around trying to measure a kite accurately.
Hi Andrash,
The number on the wingtip is used as a general guide to the kite's suitability to wind speed. This has been pretty much a good reference for us for a long time. It's only when a brand comes along and posts a size much smaller than the actual size to make everyone think it is super powerful that things start getting a bit fuzzy.
Kite size on the wingtip is only indicative of the sqm of a kite anyway. Often the kite can be up to half a sqm out, but more than this and it should be rounded up or down to the nearest meter.
Power comes from too many other variables such as Aspect ratio, wing profile, projected area, and lift/drag coefficients. Some kites are designed to be grunty with smaller wind ranges and others rely on apparent wind power and have larger wind ranges.
Too many variables as mentioned for the number to be anything other than a VERY rough guide.
I flew an 8m Catalyst once recently on the beach next to another surf kite. We looked up and they looked identical in size. I mentioned to the owner, I didn't know you had an 8m", he said, "I don't, this is a 6". Hmmmm!
DM
