A ROTOR INSTEAD OF A PARACHUTE | MODEL CONSTRUCTION

General interest competitions rakatomalala (the first open championship of Asia and championship of Russia) resulted in a model of Rotorua (class Ѕ9А) Russian athlete Vladimir Menshikov. Will talk about it in detail. This model is schematically recall the development of the first of rotochutes (1994 — 1996) at the dawn of this category. It was then suggested that a similar version V. Menshikov. But the current model is at a higher technical level. It does not apply to the type of rotochutes container type. The body of the model consists of four blades made from balsa plates with a thickness of 1 mm. folded along the axis of the model, each blade, or rather its width (chord), is 1/4 of the circumference of a circle with a diameter of 40 mm.

Structurally, the model rotocut consists of three elements: fairing, main rotor and tail part (motor unit).

Fairing is molded from two or three layers of glass, of a thickness of 0.03 mm on the mandrel ogive shape with slightly blunted apex of greatest diameter of 39.8 mm. After curing the binder fairing cut along the length to a size of 90 mm butt on a lathe, then glued two ring frames (9, 10) made of balsa wood with a thickness of 1 mm at the distance of 50 mm, the other at a distance of 82 mm from the top of the model. The thickness of both webs — 6 mm. Above the upper frame, make four holes with a diameter of 1.2 mm and have them cross (diametrically). They serve for threading rubber bands return. To the lower frame (10) attach the crossbar (12), sawn from glass fiber plastic with thickness of 0.5 mm are glued on the edges of the four U-shaped hinged hinge blades (11). In the side walls of these nodes drilled holes of 1 mm diameter for fixing the axes of rotation of the blades.

In the center of the joint drill a 5 mm hole for sticking the mount Assembly of the model.

Based on rod length of 170 mm and a diameter of 5 mm are made of carbon fiber. The upper end (the end) it will later be pasted on “the crown” of the head fairing. Below it is attached to a thread suspension model (28) and the container (14) for additional (stabilizing) of the tape. Container — tube made of fiberglass with a diameter of 11 mm and a length of 40 mm. It is connected to the pole through the sleeve (27), carved from balsa. Towards the bottom of the container re-attach the two balsa plates to the frame (15). It performs the role of supporting the folding blades. Attach the stem and fairing, kleiva it in his “the crown” and in the sleeve (27) inserted into the container (14).

The main rotor model of the four blades. They are made of balsa plate with a thickness of 1 mm. the balsa Blank is pre-steamed, is applied to the mandrel (preferably of aluminum or plastic) and wrapped with flat rubber tape (to prevent dents). After drying, cut to lengths of 330 mm and a width of 28 mm. And the sides (cutting line) should deviate from the centerline of the mandrel 4°. This is done in order to deliberately provide a geometric twist of the blade.

Model rotocut class S9N V. Menshikov (Uray)

Model rotocut class S9N V. Menshikov (Urai uriman):

1 — fairing; 2 — gum disclosing blades; 3 — lining; 4 — suspension of the rake blades; 5 — blade; 6 — motor; 7 — stabilizer; 8 — retainer MRD; 9, 10, 15, 18 frames; 11 — U-shaped bracket of the suspension unit; 12 — cross; 13 — rod fairing; 14 — container; 16 — movable piston rod; 17 — movable rod; 19 — rib blade; 20 — ending; 21 — polonaruwa; 22— the holder; 23 — frame; 24 — thread suspension model; 25 — anti-roll tape; 26 — the case of MRD; 27 — bushing (balsa); 28 thread suspension

To the lower concave surface of the blades 10 glue pads (kind of ribs), made from carbon fabric. At the beginning on the mandrel with a diameter of 38 mm is molded a cylindrical tube, which is then cut into rings of width 1.5 mm. and Then cut it into four segments (arcs). Pasted on the blade, they provide rigidity and shape of a quarter circle. To one end of each of the blades is fastened the lever is made of Linden slats with a length of 50 mm and extending beyond the slice (edge) of the blade of 5 mm. Side of her celluloid strengthen and adjust to the U-shaped hinge node head fairing. Then drill a hole for the axis of rotation and the kick from the blade. At a distance of 30 mm from the edge fasten the elastic return of the blade, tying the bottom knot.

To the tip (20) of the blades inside are glued the balsa segments for the formation of connections, and mounting of the motor unit. They are made so. Balsa veneer thickness 0.8 mm (pre-moistened) on the mandrel with a diameter of 37 mm Flex cylinder with a length of 20 mm After drying to either end of the stick ring width of 6 mm and a diameter of 37 mm from thin (0.3 — 0.5 mm) of fiberglass. Then cut into four pieces and fastened to the blade (in the drawing).

Motor block represents the tail of an ordinary model rocket sporting class. Its body is laminated of two layers of glass, of a thickness of 0.03 mm on the mandrel arched form. After drying the resin, the mandrel with the workpiece clamped in the machine tool handle and butt to the length 125 mm. To the lower edge glue three of the stabilizer, is made of balsa wood with a thickness of 0,7 mm. To one of them fastened the latch mrad (8), the curved steel wire with a diameter of 0.6 mm. In the upper part glued to the balsa connecting the clip (22) sirimau 15 mm and a mounting ring with an inner diameter of 32 mm. Along one of the stabilizers attach the free end of the filament suspension model. It is made of Kevlar, its length about 1.5 m, the upper end connected with a stabilizing brake band.

The model preparation to start conducting so. Check the correct mounting of the blades. Their angle of “V” is about 5°, the tension of the elastic bands return the same. Then fold stabilizing the fly and placed in a container that bends to the center of the blade and put the motor block on the connecting clip, which form the four elements on the free ends of the blades.

The starting mass of the model of rotachute without MRD is 17.5 g.

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