The technical aspect


Contents


The kite


    I propose you to build a Rokkaku. Let me tell you at first that the Rokkaku was initialy design for kite fighting in japan. You can then imagine it is very effective and strong, and will be quite reliable if used as a carrier. He is widely used for photography from a messenger, too. This is the kite we need !


a flying rokkaku    The size of the rokkaku depends on the wind you are used to face in your countryside, and the weight of the glider you intend to tow. For light airplane (hlg, and glider up to 1 kg), I think that a 2m high Rokkaku is to be used. The sail area is great enough to keep the line taut, and the kite is than still easy to handle when drew up. He will fly even with quite strong winds, to tow heavier gliders. A bigger kite would be usefull for wider sailplane, or light winds, but then the stuff around the kite would be quite more unusual : strong line, big carbon spar....
   You could also use a big "delta" kite, you may find plan for such kite on the web...
   For a first attemp, a 2m rokkaku looks good. If you are interested, you can built a family of rokkau, with as many size as many wind force.

    You need to cut half the kite in a carton board, in order to have the shape (a "template" would be the accurate word ?) and then be able to draw it on the fabric, and its symetric side. For this follow the small plan display on this page, with L=40cm for a 2m high kite. Add 1cm of spi fabric all around the different patch, in order to make an hem on the edge.
   All the spar will be made of 8mm carbon or hard wood. To allow the rokkaku to fly, it needs diedral to give it its stability. For this you have to bend the horizontal spar as exposed on the drawing, by streching a string between its extremities. Without this diedral, the kite would not be reliable.


   And then the bridles : they are responsible of the flying skills of the kite. You need to be quite precise in the lengh of each one. Lets have a look on the drawing ! You have to make triangles A,A',A" and B,B',B" with AA"=A'A"=BB"=B'B". The points A, A', B and B' are the middles of each half span of the kite. Then a small bridle, whose lengh must be adjustable, links A" and B". The kite line will bee hanged in A". You can then fly it !

And now, try the sewing machine !!


The lifting messenger



   The messenger must be built with care to be reliable. The principle of all the different messengers is the same, but there are many sort that exists : I propose you one that I have tried. It climb until it reaches a stop on the line, and then shut down and go back down. Here is a precise drawing of the mechanism.
the device ...
the messenger according to 'Thyssen'    It is not me that draws this, but Anthony Thyssen, whose web site is really interesting for the messenger builder. I made the same as him, but with all lengh x1.5. Take a look on his site !
   Apart from the shuting down mechanism, the sails on the messenger are the same as on the kite. This sail is only smaller, and the carbon spars are not so stiff : 6mm for the body, and 4mm for the sail.

    Go on his site, and then tell me if you have unsolved problems about glider towing.



Some tips

This was not the same messenger


   You need to know some things to use this device, that you would learn by using it, but by knowing it before, you will save time...



That's all, now you can try it !


Anyway, enjoy your flying with your kite !!!!


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