http://www.youtube.com/watch?v=40nKu_oTK1U

That was great! Really a must watch.

haha haha :singing:

:shocked2:

Airfoils sections that are reflexed are autostable in pitch. Dihedral is the same thing when looking at the kite from front or back, and creates aotostability in roll, just as it does in an aircraft. And guess what - apply the logic to the yaw axis and sweepback will give you yaw resistance.

Peter Lynn has been working on applications of this for show kites that are shaped via thru-cords instead of ribs, with some patents pending if not already granted.

krumly

powerkiting - you're doing it wrong

That LEI is so versatile you can fly it with a single line too. Amazing

Wonder if I can fly my FB kites like that!

@krumly: thanks for your explanations !

i just wish that the upcoming peter lynn tubekites would have real autozenit ! that would be totally awesome... but probably not possible with rigid tubes..

btw, any news/rumours about new kites from PL ?

Herc-

I know nothing about new PL kites.

One of the main reason most/many Arcs seek zenith is their center of gravity is behind their 'center of lateral resistance.' Basically as the kite fall soff to one side, the there is lateral pressure that pivots it around its CG and turns it back up and into the wind. LEI's have their weight so far forward that the lateral pressure generally pushes it away from the center of the window, and it falls off and down.

krumly

tube what?

yes.. a tubekite might be coming from PL - was discussed on arcusers.net , if i remember right.. or here ?

@krumly: thanks for your autozenit explanation! now it comes all together in my mind:

PL arcs have a very even mass distribution --> centre of mass is more in the middle of the kite, compared to tubekites where the centre of mass is far in front due to the heavy leading edge.
they also have a reflex profile, wich moves the centre of pressure closer to the leading edge (see image below)
so centre of mass if far behind centre of pressure. if the kite is at the edge of the window, this results in a a torque that rotates the kite towards the zenit.. emergent feature !

so tubekites could have autozenit, if
1. the leading edge would be much lighter, mass evenly distributed over the kite
2. there would be some kind of (adaptive) reflex profile (may be achived by forming an upbend at the end of the struts? or some pre-tensioning of the sail close to the trailing edge?)

or if you make a cheap hack and put weights at the struts or a tail... someone tried that?

http://2e5.com/kite/yagu/sle/

Quote:

Autozenith The unbridled Yagu uses small bike lights on the rear pigtails to induce autozenith when flying single line. Yagu SLE uses a pair of Danish 5kr coins to serve the same function. The Danish mint thinks that small denomination coins should double as kite stabilizers and conveniently include a hole in the center. I attach one coin to each rear tip inside the kite. "Can you really bribe a kite into stability?" I hear you ponder. You bet! In fact kites to prefer "hard currency" and won't respond to paper money, no matter how large the denomination. Here's how it works: The drawing above is a kite pilot view, where the LE is facing you. The kite is leaning over to its left side, but the LE is still facing the wind flow. When Yagu moves towards one side of the window, the weight at the rear wingtips cause them to sag. This sag means a change in tip AOA and net lift generated in the opposite direction. The force involved is proportional to displacement to each side of the window. The exact same lean + gravity autozenith effect is present in other kite styles as well. E.g. a classic Eddy kite is zenith seeking because the bridle center is in front of the weight center.

alot of the "newer" inflatables will sit over your head after a trick gone wrong and/or your riding unhooked and let go of the bar.......key word is sit not autozenith........keep in mind autozenith is a much as climbing from 8 or 4 oclock to 12 as it is to sit there between 11 and 1 oclock............

be careful though, try one and you might have to do a quiver reshuffle especially if youre on the water................it happens

another quite different but breathtaking example of this V-shape stability:

http://www.youtube.com/watch?v=Ac0miuyXV4Q