Page 3 of 7

Re: Switchkites - Element?

Posted: Fri Jan 27, 2012 10:13 pm
by Laughingman
eree wrote:
Laughingman wrote:Hi Bill
Can you tell us the aspect ratio of the switch kite line up? If they are different from size to size then just pick the largest common size.
i think AR is not a much importance if you don't know the profile of the wing of the kite.
if different AR kites have the same low wing profile you never have good low end for the heavier riders.
so good luck if you are heavy...
Hi Eree

I come in between 75 kg and 80 kg depending on the time of year. Not sure if that would be considered heavier or not.
What I am looking for is a larger kite for those lighter wind days which is not so difficult for me to edge against. I've read that higher AR allows the kite to fly further upwind (and past the window if you are not careful) so more difficult to fly but if you are good at it you can likely find that sweet spot most days and rocket upwind.... I think it is worth mentioning that I prefer to ride OR Makos most of the time.
If you have more to add to help me in my search for my perfect quiver please feel free to share!

Re: Switchkites - Element?

Posted: Fri Jan 27, 2012 11:00 pm
by eree
Laughingman wrote:I come in between 75 kg and 80 kg depending on the time of year. Not sure if that would be considered heavier or not.
What I am looking for is a larger kite for those lighter wind days which is not so difficult for me to edge against. I've read that higher AR allows the kite to fly further upwind (and past the window if you are not careful) so more difficult to fly but if you are good at it you can likely find that sweet spot most days and rocket upwind.... I think it is worth mentioning that I prefer to ride OR Makos most of the time.
If you have more to add to help me in my search for my perfect quiver please feel free to share!
i think you have just the perfect weight for it.

well i'm 20 kg bigger. so you can enjoy switchkite gear just fine, i'm sure

Re: Switchkites - Element?

Posted: Sat Jan 28, 2012 6:27 am
by Hansen Design
Eree:
Agree the AR is only one of many parameters blended into a final design. Profiles and their spanwise AOA and morphing are key determining factors and somewhat proprietary to most designers and brands. That said, attached is the Switch Method 9 center profile for those interested.

I tend to vary the depth of profiles between 12-15% depending on kite models and size with max draft between 17 - 25% (on inflato kites) and morph them to 0-5% and more draft aft in the wingtips. The constant curve leading edge on my designs make the profiles appear flatter because the kite is smoothly sculpted from tip to tip without angled joints but the profiles are anything but flat.

Many heavyweights prefer 'bucket kites' with substantial coning which tend to sit back in the window and pull hard even at low speeds. To me, that type of kite is one dimensional and inefficient with regards to upwind ability making them less desirable for all-round use. It is pretty well known by now that the Method is very powerful for its flat area size and also very efficient upwind. The Nitro is also known for rapidly generating power with great upwind angle so heavyweights really do have a choice and no longer have to settle for 'tractor' style mow-the-lawn kites.
Cheers! :thumb:
eree wrote:I think AR is not a much importance if you don't know the profile of the wing of the kite. If different AR kites have the same low wing profile you never have good low end for the heavier riders. So good luck if you are heavy...
Method-Profile.jpg
Method-Profile.jpg (22.66 KiB) Viewed 2150 times

Re: Switchkites - Element?

Posted: Sat Jan 28, 2012 5:01 pm
by Telekiter
Bill - have you ever contemplated solving the issue of kites ripping along the struts on high speed impacts?

I recon it would be an easy task realy. A simple solution would be adding a stripe (possibly 2" wide) of new slightly flexibel material that runs all along the LE and separates the LE from the canopy. This way, when the LE bends on a high speed impact the tensional forces normaly transfered to the canopy (ripping it) is absorbed by the new flexing mtrl.

soooo what do you think?

/Urban.

Re: Switchkites - Element?

Posted: Sun Jan 29, 2012 4:14 am
by Hansen Design
Urban:
Interesting question and possible solution.
Flexible materials are generally prone to quick degradation of properties due to UV exposure and profile changes also might present a possible problem with your suggestion but it does have some merit. We already reinforce the kites along the struts and the LE edge canopy-attach seam. Constant curve LE design also helps because it eliminates the corners at the struts where the tearing you mention usually occurs. We clearly would take corrective action if we found a significant problem with our current build. Kites are a form of aircraft and high speed impacts are potentially damaging even when the construction is based on their high probability. I do not believe damage can be totally eliminated - even with a large increase in cost and/or weight so a decision must be made at some point in that regard.

When I was building high performance stunt kites, I had to explain more than once that kites are aircraft and Boeing does not warranty their airliners against damage from crashes either...
Cheers! :thumb:
Telekiter wrote:Bill - have you ever contemplated solving the issue of kites ripping along the struts on high speed impacts?

I recon it would be an easy task realy. A simple solution would be adding a stripe (possibly 2" wide) of new slightly flexibel material that runs all along the LE and separates the LE from the canopy. This way, when the LE bends on a high speed impact the tensional forces normaly transfered to the canopy (ripping it) is absorbed by the new flexing mtrl.

soooo what do you think?

/Urban.

Re: Switchkites - Element?

Posted: Sun Jan 29, 2012 6:15 am
by L0KI
Ocean Rodeo has had a dacron strip about two inches wide that runs from end to end on the kite at about a foot back from the leading edge. A great idea. Nobody else bothers to go to the expense to add it on their kites.

Re: Switchkites - Element?

Posted: Sun Jan 29, 2012 10:59 am
by Hansen Design
OnB:
Not a matter of cost. I prefer to avoid 'hard' spots caused by fabric discontinuities or transverse seams in the max draft area of the profile. I do make a functional fabric orientation change further aft to reduce stretch and help keep the draft forward. Other designers may have different preferences.
Cheers! :thumb:
Oldnbroken wrote:Ocean Rodeo has had a dacron strip about two inches wide that runs from end to end on the kite at about a foot back from the leading edge. A great idea. Nobody else bothers to go to the expense to add it on their kites.
Fabric-Orientation1a.jpg
Fabric-Orientation1a.jpg (72.54 KiB) Viewed 1946 times

Re: Switchkites - Element?

Posted: Sun Jan 29, 2012 12:37 pm
by naishdude
Onb.....its like toilet paper, it never tears off at the perforation..... :lol:
dude :cool2:

Re: Switchkites - Element?

Posted: Sun Jan 29, 2012 12:48 pm
by Telekiter
The BEST nemesis from 08 and 09 also had adressed this by adding reinforcement at the intersection of the LE and struts. Dont know if it worked as intended has i never had any hard crashes with mine.

Re: Switchkites - Element?

Posted: Mon Jan 30, 2012 1:54 am
by lorenzods
Hi guys,

I have a 10m nitro and am looking at the 13m Element for light winds.
I have been kiting 5years, have 2 TT big & small + strapless surfboard, weigh +- 95kg.
Conditions: 12kn-35kn, flat, chop, waves 2' max
water and snow

Does anybody know how the 13m Element compares to the 14m Nitro.

I like the boost, upwind & hang time of the nitro but figured to ride surfboards in light winds...

Lorenzo