AT THE START — “PENNANT-9”

Flying clubs Directive of the Central Committee of DOSAAF of may 25, 1979 allowed to build gliders only on the drawings approved by the technical committees of local federations of hang gliding. Besides flying a self-built devices should be performed only after examination by the representatives of the technical commissions in the field. This decision was due to the need to ensure safety both during training and during sports performances and is intended to nullify the persisting injuries.

One of the first devices recommended by the technical Commission of the Moscow Federation as the basic sport model of the open class — the glider “pennant-9”. It was designed on the basis of serial French office SK-2 provided to us by M. Hochberg. “Vympel” is quite simple and reliable aircraft with high performance characteristics, particularly with excellent maneuverability. Despite the small Qualinost (40′), it has sufficient stability and good handling. Such characteristics are obtained by selection of the stiffness of the lateral pipes, the use of reinforcing sleeves, hard profiling the Central part of the dome (front — shaped tube and the rear using a special stand).

With a frame of this glider you can use three sets of sails of various sizes, which have different aerodynamic characteristics. Each sail in two versions — single and double. Sail with double surface equipped with profiled battens extending over the entire chord of the wing and supported the front ends of the main tube of the frame.

THE BASIC DATA UNIT. Scope — of 9.55 m, sail area — 16,4 m², the speed range — 25— 60 km/h, glide ratio — 8. A complete set of working drawings of the apparatus distributed by the Federation to the leading deltaclub countries to study and improvement in relation to their own production capabilities.

The main differences between the model of the “pennant-9” described in this issue of the magazine, from the SC-2 with the following:

for sewing sails instead of Dacron with a width of 914 mm applied domestic Dacron (fabric “yacht”) with a width of 800 mm, which led to a change in sail plan, number of stitches and locations lat;
introduced a new design of the Central unit;
applied armour, shaped to the front of the pipe.

The need produced improvements shown by comparative tests of gliders SK-2 and “Vympel-9”. Key features of “Vympel” did not differ from the SK-2, and the result of the flight tests was the recommendation of the Bureau of the Moscow Federation of hang-gliding to use the design “of the Pennant-9” for making it in sections and deltaclub with practical experience in the design and construction of complex devices. Drawings of the apparatus coordinated with the technical Committee of all-Union Federation of hang-gliding.

The Glider “Pennant-9”:

1 — sail, 2 — bow knot, 3 — fairing, 4 — pole 5 — side tube, 6 — reinforcing sleeve (stocking), 7 — transverse tube, 8 — strut mounting sails, 9 — keel, 10 — off, 11 — line control, 12 — instrument block 13 — a set of stretch marks, 14 — LVL, 15 — side node, 16 — lock plate 17 — kit of supplies and accessories, 18 cover, 19 — gear.

The frame of the apparatus shown in figures 1, 2 and 4. From the previously described conventional structures it is different shaped fairing in front of the keel tube and the leading edges and the design of the Central unit. The ordinates of the profile of the fairing is shown in figure 3. We note that all the parts of the frame are very technological and particular difficulties in their manufacture do not arise.

Sail (cupola) consists of two half-wings. Their design is absolutely identical, the only difference is that the right wing is a mirror image of the left. Each is sewn from five direct asanovich panels; their location is shown in figure 2. Each wing is supported by the family armor, five of which are located parallel to the keel. Ending polycrylic form two armor, they are placed at an angle to the Central beam.

The Mylar panels are joined together by parallel lines of seam “zigzag”. Luterman a width of 35 mm are formed in the overlap of the longitudinal seams. Laderman for the first variant of the sail reach the seam of the sleeve side pipes, while the armor from the first to the fifth straight and sixth and seventh have to be profiled and ends to lean on the side of the pipe.

For the second option sail all battens are profiled, their laderman reach the side tubes themselves armor based front ends to the lateral pipe.

Proper manufacture and installation of the sail can be controlled at the table. It is possible to check the line sagging rear edge to which the glider is mounted with the dome it is necessary to have a control stick up. One of the reasons for significant deviations of the line sagging from the table are errors in the stitching of cloth; the only measure of correction of this defect is the alteration of the entire seam. It is particularly important to achieve the symmetry of the right and left polacrilin, otherwise inevitable emergence of effect of “stalling the wing”, a very unpleasant and dangerous for the pilot.

Stretching and fittings shown on the drawings. All these design elements it is advisable to do of stainless steel materials. The cables should be in the plastic shell; buckles, adjusting straps, bolts and fingers to have a protective coating.

V. BOUGROV, N. GRUSHIN, Moscow Federation of hang-gliding

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