Competition C2 like traction kite

4.6 m²

Note from the traductor

I‘ve tried to obtain the best traduction as possible. (The original plan was in German)

I‘m not an native english either german speaking person, so errors can happen.

I‘ve traduct this plan for my personnal use.

You can use it as you own use, but without my responsability.

You use this plan at your own risk.

C.T.

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Additionnal notes about the briddle

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• Wingspan: 460 cm or 15 feet
• Deep one:- max. 120 cm

- min. 30 cm

• Aspect Ratio: ca. 4

• ca. 20m Spinnaker nylon or polyester
• 5m Fabric tape 25mm broad
• 15-16m Dacron 25mm broad
• 200m Bridle line Cyclone PES 50 or 70;
• 50m encased Kevlar or Spectra cord for sewing on on the profiles;

alternative: Belt for loops

• each quantity polyester yarn

This kite was developed for the professional application in Buggy races. Beginners in the four-flax reaching or Buggy race should fall back better to a normal Quadrifoil or a similar four liner, since the handling of the Competition is everything else as simple. I‘ve tried to measured an existing kite. It can have measurements inaccuracies.

The Competition is a bi-elliptical staffless stunt kite. Contrary to other foils the Competition does not possess rectangular and large air intake. The air intake are completely on the lower surface kites cover and soil enclose the profile completely and ensure so a large profile loyalty. The two outside chambers are in the front closed - which is to prevent the decrease of air pressure in the wingtips - holes in the profiles supplied with air pressure. The Competition to build is a very time-consuming project. I‘ve passed a full day to cut the material, sewed two full days and attached the bridles fora full. Thus do not despair, if it lasts longer to built than a Speedwing. With this structural drawing it is extremely important to read and understand everythings carefully, because some steps appear only clear if you have knowledge of the general context. So, and now geht's loosely. Have fun!

The soil or the cover kites consists of a half ellipse for the leading edge and one of two so-called half ellipses, ever for the trailling edge. In the following table are the construction Data.Y above and y-down. During entry into a coordinate system the center line of the Biellipse is the x axis. one lays on upward y-above and y-down downward. The mesurement data in soil and cover are for the Competition C2 are in cm and include seam and seam margin (so far necessary). It can however never harm to cut the sections out somewhat longer than indicated. By pulling the cloth, incorrect material transfer of the sewing machine or other adverse circumstances it can happens inaccuracies: admit simply add 10cm more of margin. The column per cent displays the size of the profile in the comparison to the original size, inserted in the respective place. This is important, since due to ellipse all profiles are not equivalent large. With this column it should not be a problem to scale the profiles suitably. With the adaption it is important that the upper half ellipse (speak the upper y-values) is kept. The lower half ellipse results then inevitably from the length of the profiles. Thus clear away y-above-values on template and if necessary the y-down-value will be increased. It is not necessary to interpolate the points with Splines. Straight line course is sufficient and is also easier to sew.

Figure 2: The ellipse up to the center, all specification in cm.

For the right half the ellipse must be mirrored. When mirrored it is to be made certain that the chamber in the center may be measured only to the half. The color specification refers to the color design of a original Competition C2. The covering or floor parts was not arranged concave/convex.

The bridle is to be designed as a mirror-image. Therefore only IE left balance (similar to ellipse) is indicated here. In the original of the Competition belt loops are fastened to the soil to the points of bridle, to which the bridle is fastened. The bridle is to be prevented from a rigid line manufactured. At each end of a bridle line is a loop, which approx. 10 cm long and is sewn on approx. 7 cm (s. fig. 3)

By these loops those bridle line then to the kite in the belt loops or among themselves by a loops (by means of bay nodes) fastens the lengths that bridle line resulted from measurements from loop end to loop end. In order to make balance linen, still additions for loops must be taken into consideration into the mesurement. I personally never sew bridle line, since one has then no possibility for trims more. Loops finished by over hand nodes. I proceed as follows: Per loop I mesure 1 cm linen length. This functions in any case with Cyclone PES 70 cord around the loop to nodes, i draws a mark at 1 cm and one at 17cm, in each case from the end of the line counted. The two points are superimposed and the loop is knoten. The markings must be afterwards under the node and beyond the loop.

Figure 3: The final loop of a bridle line

The bridle is fastened as follows:

Ever four line per profile (primary line), in fig. 4 marked by 1. These four line are indicated into a further line loop (secondary line), in fig. 4 by 2. The three neighbouring secondary line are indicated again into a further line loop (Tertiary line), in fig. 4 by 3. The four Tertiary period line run in a Schekel together (s. fig. 5). In this Schekel is also the aluminum ring, by which the brake line are pulled later.

Starting from the third chamber into the center of the chamber on the Dacron at the trailling edge belt loops are sewn on in each case from the outside (9 chamber/loops on each page of the ellipse). Into these loops those are knoten brake linen (primary linen). Per three neighbouring line who that into a further line loop (secondary linen). The three secondary linen are looped into a further line. This line runs the aluminum ring in the Schekel. This is also the line into those the flight line to be looped (as with the conventional Quadri. Thus rather longer adapt as indicated and more node insert than indicated. Reliably is safe).

Figure 5: The Quadrifoil Competition bridle system

Important: The brake line (with the three or also more nodes) must be led by the ring in the metal link. By this the traction power achieve their optimum.

The profile

The profile of the Competition was copied from an existing kite without isolating. It can have come therefore to small inaccuracies when copying. The points from the profile table are to be connected with a spline. Since the kite is elliptically arranged, the profile must be scaled on the correct size for each chamber. The pper cent collumn fued the scaling are in tab. 1. All X/Y values must be reduce/increased with the appropriate percentage. All important points, which are now discussed, refer to the main profile and must be along-scaled on modification of the size.

The point, at the that is sewn on the profile at the cover is situated with x=1,8cm on the lower surface of the profile.

Four holes for the pressure balance must be cut into the profile. If one ooverlaps with the line sewn on the profile then move the hole a little further. If belt loops are inserted into the soil, then the position of the holes are all the same.

The x-coordinates for the sewn on line or the positions of the belt loops one can take fig. 6 (mesure in cm.)

• Z is with x=1,8 cm on the lower surface of the profile
• A is with x=12 cm on the lower surface of the profile
• B is with x=34 cm on the lower surface of the profile
• C is with x=64 cm on the lower surface of the profile
• D is with x=94.5 cm on the lower surface of the profile

   It is matter of taste whether sews loops into the soil or a zigzag line on the profile. According to my opinion the zigzag line has the advantage that the course kites on the whole profile is distributed evenly; in contrast to the loop, where the course is determined on one point only. If you uses loops, then you needs the briddle line only with bay to the loops to nodes. If you uses the zigzag line, you must proceed as follows: In the places, in which the sewn on line at the soil makes the break (A-D), must a baridle line is attached. In addition one stings with a splice needle into the soil, leads the bridle cord directly over the break by the profile and breaks through on the other page again the soil. Then in accordance with fig.7 a tightening node is manufactured.

In order to build the Competition, one needs experience with staffless kites and first of all much time and patience. Because the Comp. the construction has other foil than conventional mats became surely more time-consuming. Cover and soil consist not of a section, but of individual strips, which must be first processed and together-sewn.

First, the templates for the soil, the cover and the profiles must be manufactured. In addition the data from the appropriate tables are transmitted to sturdy pasteboard and the templates are then cut out. The pasteboard should be so stable that it does not away-burn with the first contact with a soldering iron. The sections of the cover can be cut out as simple trapezoids (or as ellipse, which is then cut in strips. Then a seam addition must be taken into consideration by 1 cm) at each long side. With the sections of the soil a light curve must be cut out in front at the air inlet.
This curve results in later the air inlet. In fig. 8 this is again coloured represented. The normal trapezoid of the upper ellipse (values y-above) is light-grey. Dark grey the curve is represented, which must be still cut out from the floor parts. This circular arc has a maximum exactly in the center of the line, which connects the two y-values (maximum 4-5 cm with each floor part).

A special feature occurs with the two outside chambers. These are course-sewn above and possess no air inlet. The printing is structured by the holes in the profiles. The sections for the two outside chambers are to be adapted thus somewhat differently than the other sections. On the air inlet edge of these two sections no curve is set and also no Dacron, but ever for under and upper section a seam addition is sewn on by 1.5 cm added. Then the two sections at the air inlet edge are normally quilted and the seam addition on the top side with a zigzag pass is sewed. It is alike to all soil and cover sections that at the left and to right page a seam addition by 1 cm is admitted. On this seam addition later the profile is sewn

Figure 8: The air inlet

In order to cut the foil out, GET one so forwards:

• One draws a parallel to the air inlet edge in the distance 4-5cm. of this abbott and is for all floor parts evenly to be kept.
• One marks the focal point of this line.
• Now a set soil is drawn. It begins its maximum at the focal point of the drawn in line at the air inlet edge (left), achieved and ends again at the air inlet edge (on the right).
• The marked section must be only cut out.

After all soil and cover sections were cut out, can be begun with the sewing work. The cover sections (up to the two outside) are set in at the air inlet edge with Dacron. In addition the Dacron is centrically folded and the air inlet edge is shifted into the crease. Sew with 3 zigzag pass.

With the following trick this work goes more easily and faster: The Dacron is not suitably cut and sewn on then, but it will proceed as follows: The third section is shifted and stitched into the break (with 3 zigzag stich). And further-sew this type shift the next section into the break receive one a chain from cover sections, which splits afterwards only must become hot. Exactly the same with the floor parts will proceed. Only with the third section begin also here. These are set in however with fabric tape. After all covering and floor parts were strengthened, can be begun with the assembling of the cover and the soil.

The outside two sections of the ellipse are differently sewn than the remainder: in each case sew soil to the cover. The seam addition depends on the half width of the Dacrons used for setting in. Repeat for both sections and both pages. The seam addition also with 3 pass zigzag quilted on the cover.

The two developed sections now lengthwise together-sew. In addition at the seam line cover/soil begin and only the cover seam, then the soil seam quilt. With the soil seam of the belt loops think, if without the zigzag line one does. Now together-quilt the complete cover. Seam addition 1 cm. at the edge (seam 2./3. Part) that dier seam line with the Dacron of the third section lock soil/cover of the second section cleanly. After, which was sewn complete cover, the soil inserted. Proceed as follows in addition:

• Cover so put that always the seam addition between the chambers, at which the soil is sewn on shows after right (fig. 9).
• On this seam addition in accordance with fig. 9 the floor part with few passes is sewn on. Shift in addition the floor part onto the cover section that those is appropriate for crease of the fabric tape of the soil justified with the open end of the Dacrons.
• Now the seam addition is turned over and the whole on the other page is repeated. (experts can sew on naturally also directly both floor parts in a step.)
• If one fastened ever two floor parts to the Dacron of the cover, then the two floor parts can be together-quilted after the length.
• In this manner one works through the whole soil.

For the profiles templates in different sizes must be manufactured. The values for the scaling can be refered from tab. 1. The profiles can be scaled with a still-picture projector, a copier or a good diagram program (e.g. Corel Draw). The values can be converted also by hand, by taking the new length and by the old dividing all X/Y values must then by this calculated value is multiplied. Now the profiles are inserted.
NOTE: In no case forget the holes for the pressure balance!!! # In the together-sewn kite upper and lower part the seam additions are located inward away. On these seam additions the profiles are sewn. First the profiles are sewn on the cover. In addition always put the profile with point Z to the Dacron fold to stitch and (with zigzag stitch). Repeat with all profiles. It makes certain that point Z in the same place is always sewn on. If all profiles on the cover are sewed, they must be sewed on the soil. The most difficult is it here to stitch the roundness of the profile nose. Always make to two passes, profile position correct and further-sew. If all profiles are inserted, the two outside seams must be closed. Don‘t put hole on the edge profiles, it must however belt loops for a bridle suspension be attached. The points for the belt loops one keeps if one the main profile on 28 cm reduced. The points A-D are along-reduced. In these places then belt loops must be inserted.

Now the trailling edge is sewn. In addition it must be brought first in form. The unneeded material is removed in addition approx. 1-1.5cm from the profile ends. It is advisable to draw in between the individual section ends lines and quilt these. Then the unneeded material is centrically folded cut off, Dacron, the trimmed dragging edge is shifted into the crease and quilted with 3 zigzag pass. On the Dacron still belt loops for the brake linen must be attached now. These are attached from the outside, 9 on each page, starting from the 3rd chamber always in the center of the respective chamber. Thus the sewing work is terminated, now the bridle must be looped and fixed. Afterwards is the kite. Possibly still smaller trim work on the bridle is necessary. Good Flight !!!!!!!!!!!!!!

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