An ornithopter is a heavier-than-air aircraft that is supported in flight by the reactions of the air with its planes, which are given a flapping motion.
Ornithopters have been of interest since ancient times, because this is how birds fly.
There are even drawings of an ornithopter made by Leonardo DeVinci.
To make a homemade ornithopter flywheel with your own hands, you will need the following consumables:
In the picture below you can see drawings for making an ornithopter with your own hands.
For manufacturing, it is better to use linden or balsa; you can use carbon tubes or, as our Chinese comrades do, plastic rods. However, you can plan out the silt of any tree - birch, linden, etc.
The connection of the frame slats is made using a tongue-and-groove type and is wrapped with threads impregnated with glue.
The leading edges of the wings are also tied to the levers with threads, but before that a hole is made in them through which the lever spike is passed.
The bearing of the rubber motor shaft and levers can be made from wire insulation, or from parts of the rod from the handle; they are also wound with threads and the threads are impregnated with glue. A crankshaft similar to the one in the figure is bent from the wire, then a bead is put on it and it is inserted into the bearing, after which the hook is bent (see figure). The levers are bent and after they are inserted, their ends are bent.
The stabilizer tail is fastened from slats in the same way as the frame, after which wire is wound to it with threads and bent as in the photo.
A cut is made in the ornithopter frame into which the wire is inserted, after which it is wrapped with thread and glued.
Next, connecting rods are made, we make them from bamboo, it’s just convenient to break off thin sticks from it, we put tubes of wire insulation on their ends, we burn holes in the tubes, heat the wire over a candle and quickly pierce the tube with it. We make the tubes longer from the end where the stick is inserted; you will need this for adjustment.
We stretch two rubber bands between the hooks and twist the rubber motor, but not too much, and let go, the wings should begin to move, if their stroke is not the same, then bend the front crank.
Next, we lubricate the central rib and the edge slats with rubber glue, put our aircraft on the film and straighten it so that the film sags, but not much, we try to do it equally on both sides, otherwise it will fly in circles.
When using rubber cement, it is advisable to back everything up with small strips of tape.
We also make sure that the wings are identical.
Be sure to let the glue dry and then launch!
If you don't quite understand the construction, watch the video below.
Video of making an ornithopter with your own hands
And here is the flight of a mini version of an ornithopter weighing 3 grams.
How to set up an ornithopter
:If your bird is diving, bend its tail up; if it is pitching (raising its nose and falling), then lower it, on the contrary. Also, by changing the length of the connecting rods, we achieve greater stability and traction during flight.
If everything is assembled correctly, this model gains altitude in a straight line, after which it slowly flaps its wings and then sits down, slightly tucking its wings. The indoor model looks more like a dragonfly when it climbs, the flapping frequency reaches 20Hz. When assembling a larger model, the flight time, height and entertainment value of the flight increase, the frequency of swings decreases, but you need a more powerful and longer elastic band
However, flying on a rubber motor is not very exciting. Much more interesting is a radio-controlled ornithopter.
How to make a radio controlled ornithopter
The video above shows how a homemade ornithopter is equipped with a motor and radio control.
This video is a continuation of the one shown in the ornithopter making section.
Happy flying!
An ornithopter is a heavier-than-air aircraft that is supported in flight by the reactions of the air with its planes, which are given a flapping motion.
Ornithopters have been of interest since ancient times, because this is how birds fly.
There are even drawings of an ornithopter made by Leonardo DeVinci.
To make a homemade ornithopter flywheel with your own hands, you will need the following consumables:
In the picture below you can see drawings for making an ornithopter with your own hands.
For manufacturing, it is better to use linden or balsa; you can use carbon tubes or, as our Chinese comrades do, plastic rods. However, you can plan out the silt of any tree - birch, linden, etc.
The connection of the frame slats is made using a tongue-and-groove type and is wrapped with threads impregnated with glue.
The leading edges of the wings are also tied to the levers with threads, but before that a hole is made in them through which the lever spike is passed.
The bearing of the rubber motor shaft and levers can be made from wire insulation, or from parts of the rod from the handle; they are also wound with threads and the threads are impregnated with glue. A crankshaft similar to the one in the figure is bent from the wire, then a bead is put on it and it is inserted into the bearing, after which the hook is bent (see figure). The levers are bent and after they are inserted, their ends are bent.
The stabilizer tail is fastened from slats in the same way as the frame, after which wire is wound to it with threads and bent as in the photo.
A cut is made in the ornithopter frame into which the wire is inserted, after which it is wrapped with thread and glued.
Next, connecting rods are made, we make them from bamboo, it’s just convenient to break off thin sticks from it, we put tubes of wire insulation on their ends, we burn holes in the tubes, heat the wire over a candle and quickly pierce the tube with it. We make the tubes longer from the end where the stick is inserted; you will need this for adjustment.
We stretch two rubber bands between the hooks and twist the rubber motor, but not too much, and let go, the wings should begin to move, if their stroke is not the same, then bend the front crank.
Next, we lubricate the central rib and the edge slats with rubber glue, put our aircraft on the film and straighten it so that the film sags, but not much, we try to do it equally on both sides, otherwise it will fly in circles.
When using rubber cement, it is advisable to back everything up with small strips of tape.
We also make sure that the wings are identical.
Be sure to let the glue dry and then launch!
If you don't quite understand the construction, watch the video below.
Video of making an ornithopter with your own hands
And here is the flight of a mini version of an ornithopter weighing 3 grams.
How to set up an ornithopter
:If your bird is diving, bend its tail up; if it is pitching (raising its nose and falling), then lower it, on the contrary. Also, by changing the length of the connecting rods, we achieve greater stability and traction during flight.
If everything is assembled correctly, this model gains altitude in a straight line, after which it slowly flaps its wings and then sits down, slightly tucking its wings. The indoor model looks more like a dragonfly when it climbs, the flapping frequency reaches 20Hz. When assembling a larger model, the flight time, height and entertainment value of the flight increase, the frequency of swings decreases, but you need a more powerful and longer elastic band
However, flying on a rubber motor is not very exciting. Much more interesting is a radio-controlled ornithopter.
How to make a radio controlled ornithopter
The video above shows how a homemade ornithopter is equipped with a motor and radio control.
This video is a continuation of the one shown in the ornithopter making section.
Happy flying!
Why don't people fly like birds? How they fly: the aerodynamics of the aircraft are almost the same as those of birds, although people are still working on a fully “morphable”, variable wing. During the flight we reached great heights. If you convert it into kilograms of mass and kilometers of flight, a modern airliner spends less energy than a bird. There is apparently no analogue of the helicopter principle of flight in the animal world. But still there remains some incompleteness in a person’s ability to fly.
Roman Fishman
An ancient dream, like our entire family, to fly like a bird - that is, freely flapping its wings - remains unfulfilled. This dream is so strong that although no airline or army in the world still operates a single ornithopter, the current Convention on International Civil Aviation includes its definition: “A heavier-than-air aircraft that is supported in flight primarily by the reactions of the air.” with its planes, which are given a swinging movement.”
From airplane to helicopter
However, the dream of flapping flight also has a practical side. The aerodynamic quality - the ratio of lift to drag, which determines flight efficiency - is exceptionally high in aircraft. But airplanes require expensive and complex airfields and large runways. Helicopters are more convenient in this sense; they take off and land vertically, without requiring any infrastructure. They are much more maneuverable and are even able to hover motionless. But the aerodynamic quality of helicopters is low, and an hour of their flight time is not cheap at all.
There are many attempts to cross one with the other - rotary-wing gyroplanes and tiltrotors have their fans. For solving some narrow tasks, these aircraft may even be indispensable. But still, such hybrids turn out to be not very successful: there is a well-known joke that they combine not so much the advantages as the key disadvantages of both airplanes and helicopters. But flywheels may be a suitable solution. Theoretically, they will be able to take off from a standstill, will be maneuverable up to the ability to hover in the air, and will be able to demonstrate almost aircraft-like aerodynamic quality.
But the first awkward balloonists thought, of course, not about airplanes, which did not exist yet, but about birds. It seemed that it was enough to learn to push off the air with wings - and the person would fly. With such views, of course, none of them were able to get off the ground. Winged mechanical devices made for clumsy gliding at best, as was done by the legendary Benedictine monk Aylmer, who jumped from the tower of Malmesbury Abbey in England about a thousand years ago, sustaining severe injuries.
From bird to insect
The reason for the numerous failures is clear: the very essence of flight in those years was represented rather vaguely. What gives birds lift is not the support of the air, but the special contour of the wing profile. By dividing the oncoming flow in two, it causes the air above the upper edge to move faster than above the lower edge. According to Bernoulli's law, pressure will be higher in an area with slower flow. The resulting difference between the pressure under the wing and above it creates lift. But once you start flapping your wings, this clear picture changes completely.
A well-known saying says that “according to the laws of aerodynamics, bumblebees cannot fly at all.” In principle, this is true: from the point of view of classical aerodynamics, insects and their wings are something surreal. Even in theory, they are unable to create the lift and thrust necessary for flight - unless we move from classical glider aerodynamics to new, unsteady ones. Here everything is different: turbulent turbulence, with which aircraft designers struggle tirelessly, becomes the key to flight for both the bumblebee and its relatives.
Large birds use flapping only occasionally - for example, when they need to slow down for landing or take off. This flapping plus the movement of the legs allows them to gain forward thrust so that the wing's lift comes into play. Insects flap their wings constantly, and along a special trajectory, more likely back and forth than up and down. In combination with the flexibility of the wings and a sufficient frequency of flapping, this creates turbulent vortices at their leading edge, which are “dumped” from the edge of the wing at the top and bottom points. They create sufficient lift and thrust for the bumblebee to fly.
By changing the speed of the first and second phases of movement, the insect controls the direction of these forces, maneuvering in the air. And even the bristles, bumps and irregularities on the surface of the wing - unlike a streamlined airplane wing - work to form turbulent vortices.
From Moscow to Toronto
These subtleties were not known for a long time and are still not fully understood. But it turned out that in the simplest case this is not necessary. Even before World War II, German aircraft designers successfully launched small, lightweight ornithopters using a twisted rubber band for drive. Even the famous aerodynamicist Alexander Lippisch paid tribute to their passion, and in the 1930s Eric von Holst managed to lift an ornithopter off the ground, on which an internal combustion engine was installed. However, it was not possible to create a device that could be considered as a prototype of something useful, capable of carrying at least one person or cargo. In the 1960s, Percival Spencer demonstrated the flight of an “orniplane” with a wingspan of 2.3 m and a tiny (5.7 cm3) two-stroke engine - it was piloted by an operator via cable.
A larger flywheel took off only in the early 1980s, when Valentin Kiselev, a professor at the Moscow Aviation Institute, designed a seven-kilogram device capable of taking off independently and remaining in flight. Over time, the model was freed from the cable and controlled via radio. Following in Kiselev’s footsteps in this work was his overseas colleague James Delorier. In 1991, Deslauriers received a diploma from the Fédération Internationale de l'Aéronautique for creating "the first powered, remotely controlled ornithopter." In 2006, his model UTIAS Ornithopter No. 1 took off, and soon the manned flywheel Snowbird also took off - in 14 seconds it flew about 300 m under the pilot’s muscular traction.
“This is not a completely fair result,” explains Professor Kiselev’s student, MAI graduate Andrei Melnik. “I am familiar with these structures, and they cannot be considered flywheels in the full sense of the word. The first device was equipped with a jet engine to create thrust and take off. And the second demonstrated another important thing: that human muscular strength is not enough for flapping flight. Even a trained pilot, an athlete, managed to fly only a short distance.”
The transmission converts the reciprocating movement of the engine pistons into the rotational movement of gears, and the crank transmission turns it back into reciprocating flapping of the wings. Inventors dream of making this design more efficient by directly transmitting the movements of the pistons to the wings.
From game to science
It must be said that if “useful” flapping flight has not yet been mastered, the gaming industry already feels quite confident in this area. The first small models with elastic bands appeared on sale at the end of the 19th century, and today one of the popular toys with flapping wings, an electric motor and radio control is offered by the toy robot developer company WowWee.
“I myself started with aircraft modeling,” says Andrey Melnik, “so I can imagine how demanding airplanes are for the skill of the pilot who controls them from the ground. Literally one awkward movement - and he falls into a tailspin or roll. And I can say that my experience in controlling our flywheel shows that even a child can handle this device. We have turned out to be so stable that it easily forgives all mistakes and remains in the air.”
People are reluctant to invest funds in the development of a new type of aircraft with rather dubious prospects. However, Andrey Melnik and Dmitry Shuvalov managed to convince investors that thanks to modern technologies and with the proper investments, a flywheel could be created. “We managed to find several fundamental points that had previously been misunderstood, including when I worked with Professor Kiselev,” adds the designer. — Our first models simply fell apart, unable to withstand the load. So, it was assumed that aerodynamic forces create such a load on the device. However, tests have shown that this is not the case, and the main impact is due to the inertia of the flapping wings.”
Having identified the reasons for the failures, the developers reduced the weight of the wing as much as possible - to 600 g with an area of 0.5 m 2 - and damped its impact on the fuselage. “A real surprise for us were the simulation results, which showed that the aerodynamic center of the four-wing aircraft is not somewhere between the front and rear pairs of wings, but behind them,” recalls Andrey Melnik. — To solve this problem, we had to change the geometry of the front and rear tails. But as a result, the flywheel began to confidently stay in the air.”
Tiny ornithopters are being developed around the world. As a rule, their authors try to imitate nature with greater or less accuracy, repeating the design of a flying insect. In May 2015, Peter Abbeel and Robert Dudley from the Biomimetic Millisystems Laboratory at the University of Berkeley demonstrated a very impressive take-off of a 13.2-gram flywheel from a “launcher” on the back of a six-legged microrobot.
From practice to theory
The first flight of the flywheel took place in 2012, when the device, still almost uncontrollable, flew about 100 m. Its rigid composite wings were driven by a small engine with a crank transmission. And after another six months, the improved 29-kilogram version remained in the air for as long as a half-liter fuel tank lasted - 10-15 minutes. The developers have issued RF patent No. 2488525 for their flywheel.
The fore and hind wings of the ornithopter flap in antiphase. This sharply reduces the vibrations of the device in flight and the loads arising under the influence of the inertia of the moving wings.
“Among other things, we also faced a management problem,” continues Andrey Melnik. — Vertically, the flywheel was deflected and controlled reliably, using the elevators on the tail. But in order to change course horizontally, we had to install additional winglets on the wings. By changing their position, it became possible to fully control the device in flight via a radio channel.”
It must be said that the flywheel still does not take off vertically, although it requires a very short runway for takeoff. Just 5-10 m - and he goes into the lead. This figure can be further reduced, but to create a real full-size model, the design will have to be seriously improved. According to Andrey Melnik, first of all it is necessary to abandon the crank mechanism, which is not very successful for creating flapping movements of the wings. It generates too dangerous inertial forces, which are especially strong at the upper and lower “dead points” of the oscillation. “If we take another drive that is capable of storing the energy of the last phases of movement and then using it to move in the opposite direction, it will be much more efficient,” says the designer. “This could be, for example, a pneumatic mechanism, we have such ideas.”
“The worst thing is that we still don’t understand exactly how it flies,” continues Andrei Melnik. — Both by education and skills, we are practitioners, designers, not theorists, not scientists. But we can definitely say that conventional theoretical models are not suitable for a flywheel, and our tests confirmed this. In particular, our lift coefficient turned out to be many times greater than that of a typical aircraft wing. Why? I hope someone can figure it out." Perhaps everything will really happen in the reverse order: having figured out how the flyer flies, we will finally understand the flapping flight of birds and insects.
Hi all!
As part of the program to introduce children to science and technology (let's not forget adults too), 10 sets of ornithopters were purchased. They are also sold one piece at a time: for example, at first only one ornithopter was ordered on Ali with a price of $0.72 (search for “ornithopter”), after a couple of weeks an inexpensive set of 10 pieces was noticed and purchased.
Seller Description:
100% brand new and high quality
Colour:the Color is Sent by Random
Size:32CM*41CM
Note: Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you!
Package includes: 10 Pieces
The parcel arrived surprisingly quickly - in 18 days - a black package inside of which, in a two-layer bubble wrap, was wrapped a package with assembled wings, and a package with tails, elastic bands and bamboo slats. 
Assembling an ornithopter is not difficult. To fly, you need to connect the tail and wings into a single unit using a bamboo strip, and tighten a couple of rubber rings from the kit. It turns out to be a kind of “bird” that plans well.
By the way, the bamboo supports of a pair of wings, despite the packaging, turned out to be broken. With the help of glue and thin bamboo toothpicks, I think it will be easy to fix.
The flight does not last long - the rubber band unwinds up to 10 seconds. His task is to lift the “bird higher”; further, depending on the position of the wings, it plans. Unfortunately, it hasn’t been possible to shoot a video yet, there’s not enough space in the apartment, and it’s windy outside. Test runs in the apartment end with hitting the wall.
We plan to take a longer rack and rubber to increase the flight time.
Dimensions:
Wing span - 41 cm.
The length of the bamboo slats is 14 cm.
Tail length - 16 cm.
The diameter of the rubber rings is 4.5 cm.
I think that this toy will be interesting entertainment for children in the fresh air.
Dictionary entry - ORNITHOPTER
ORNITHOPTER
[ORNITOPT'ER]
(ornitho... gr. pteron wing) a heavier-than-air aircraft with flapping wings (based on the principle of bird flight).
Rocking movements are characteristic of living organisms - due to the work of ligaments and a closed body. No organism exhibits rotation of more than 360 degrees. At the same time, mechanisms are characterized by full rotational movements, which ensure continuity of movement. Well, in fact, a car is not much like a mechanical horse. In the printing business, only then was progress achieved in the speed of publication when they switched from the printing press to rototype - i.e. from rocking and reciprocating motion to continuous rotational motion. That is why, of all aircraft with a movable wing, it is the helicopter that has become widespread - rotating wings. However, the thought of “flying like birds” did not leave the minds of the designers.
An ornithopter, or, in Russian, a macholet, is usually called an aircraft propelled by flapping wings, although if you translate the word “Ornithopter” literally, you get a “bird flyer,” that is, a device that flies like a bird. Calculations show that flapping flight at low speeds is energetically more favorable than flight with a fixed wing. This is due to the fact that the flapping wing has negative aerodynamic drag. In order for a flapping wing to create lift and thrust, it is necessary that the angle of attack of the wing changes during the movement of the wing (in birds, in addition, even when the wing moves upward, it becomes permeable to air, since the feathers that make up a significant part of the wing , move apart). To comply with this condition, there are two ways: use a rigid wing, like an airplane, and change its angle of attack using a mechanical drive, or use a flexible wing, in which the angle of attack changes due to the bending of the wing itself under the influence of air resistance forces. When using a rigid wing, it is easier to obtain a good lift-to-drag ratio during gliding flight, but rather complex kinematics are required to drive the wings. With a flexible wing, good aerodynamic quality of gliding flight is more difficult to obtain, but the flapping mechanism is simple. This principle of flight was first “mastered” by pterodactyls, and today it is successfully used by bats.
ParkHawk: flexible wing and simple mechanism
Once upon a time I saw on the Internet a model of a radio-controlled flywheel, it was called SkyBird, the model was large (about 1.7 m span, and about 2 kg in weight) with an internal combustion engine. I wanted something similar, only smaller and with an electric motor. My search led me to the ParkHawk model from Kinkade RC. In various online stores this model was offered at a price of about $200.
The shape of the flywheel is very similar to a bird; even control is realized using a tail, very similar to a bird’s tail. The ParkHawk flywheel uses the principle of a flexible wing, so the flapping mechanism only requires a simple up and down movement of the wings.
The model has a wingspan of just over a meter - 105cm, wing area - 18 square meters. dm, its flight weight is 350-380g, depending on the weight of the machines and receiver used. The wings are driven by a SPEED 300 engine (Graupner) with a two-stage 98:1 gearbox. The flight time declared by the manufacturer is 7-10 minutes, which in principle corresponds to the truth - I was not able to stay in the air for more than 7.5 minutes.
The flywheel is controlled in heading (right-left) by turning the tail relative to the longitudinal axis of the model, and in pitch (up-down) - by tilting the tail up or down. This is very similar to an all-moving glider stabilizer, only in the neutral position the tail is not mounted horizontally, but at an angle of about 30° upwards. To move the tail, 2 steering gears are used, one of which (for steering left and right) tilts along with the tail when the tail moves up and down. A mechanical mixer is organized in this way, and conventional three-channel equipment is sufficient for control.
The fuselage is made of 1.8 mm fiberglass, its outline is very similar to the body of a bird. A flapping mechanism - a motor, a gearbox and two cranks are attached to the fuselage, from which rods with ball ends go to the leading edges of the wings. Also mounted on the fuselage are batteries and a receiver with a pitch control steering gear. The roll control machine is mounted on a special frame that rotates with the tail. The tail is actually attached to the lever of this machine using two screws.
The leading edges of the wings (carbon rods with a diameter of 3 mm) are inserted into special wings, to which the flapping mechanism rods are attached. And the rear, or rather “diagonal”, edges of the wings are attached to the fuselage using standard ball ends, which gives the wings the ability to flap freely up and down.
Assembly is very easy
The flywheel is supplied with the following configuration: a fuselage and a flapping mechanism assembled on it, completely finished fabric wings (cut from one piece of fabric with glued pockets and reinforcements), a ready-made tail stabilizer and four long carbon rods - these are the edges of the wings. The set also includes a set of batteries (8 pcs 700mAh, size “AAA”) and rubber bands for attaching them.
Before assembling the model, I advise you to solder the regulator to the motor. Although this can be done later, the fact is that the fabric from which the wings are made is very easy to burn through with a soldering iron.
Assembling the kit is very simple - you need to install the steering gears, screw the tail to the steering gear lever. Next, you need to insert the front and “diagonal” edges into the pockets on the wings, screw the hinged fastening of the wings to the fuselage, and put the ball ends of the rear edges on the balls attached to the fuselage, and also snap the flapping mechanism rods to the cranks (inserted with decent force) - and wings installed. Finally, you need to secure the central part of the wing fabric to the fuselage with a screw; in this place it is reinforced with black nylon tape glued on. That's all! Assembly takes a maximum of an hour.
The receiver is glued to the fuselage with double-sided tape. The batteries supplied in the kit are secured with an elastic band, which is also included in the kit. We check the movement of the cars and wings, set the neutral of the tail - about 30° up - and you can fly!
Flying
The model is launched manually, just like a regular parkflyer. The first thing that surprises is the unusually low flight speed for a model weighing 370g and a wing area of about 18 sq.dm. It is 15-20 km/h. (here it is appropriate to recall that from the point of view of classical aerodynamics, the speed of a duck for straight flight should be about 200 km/h, and a bumblebee cannot fly at all). The flywheel gains altitude well in a straight line, but turns very slowly and lazily, and has a large lag in control. Therefore, despite the low speed, flights require an area of at least 50x50m. Allowable wind is 4-5m/s. When the wind is strong, the “bird” simply does not move against the wind, so when flying in a field in windy weather, be careful - do not let the model go far into the wind - otherwise you will have to follow it for a long time. Of course, we can’t talk about any kind of aerobatics; this is not an airplane.
But nevertheless, despite all the “laziness”, the model looks very similar to a real bird in flight, and from 60 meters away it is easily confused with “some kind of crazy” bird. To land, you just need to remove the gas by more than half, and the model will smoothly descend. The model glides quite poorly with the engine completely turned off - this is due to the flexible wing and the lack of a profile. A spectacular landing, almost like a real bird, can be achieved if you descend at about half the throttle, and when you are about 1 meter from the ground, make one or two strokes at full throttle, while taking the control stick towards you, and sharply release the gas. The "bird" will land at almost zero horizontal speed.
It should be especially said: watch out for dogs! They think that it is clumsy “meat” that flies, and I have never met a dog that would not chase my “bird” - a hunting instinct, however.
Advantages and disadvantages of the set
After several successful flights, I want to try to do “something like that,” that is, aerobatics. Since there are no ailerons, the barrels cannot be twisted, so I decided to try to make a loop. When taking the handle all the way “towards you” in forward flight, the bird simply lifted its nose upward by 30 degrees, and desperately began to try to rake upward, almost losing its horizontal speed. But the altitude gain dropped to almost zero, and it looked very funny. OK. Having leveled the model, I slightly remove the gas and, giving a little "myself", try to accelerate the model. Then - full throttle and smoothly "on yourself". The bird lifts its nose, when suddenly - crunch! - and fluttering, very much like a shot duck, the model, tumbling randomly, falls down. (It’s good that there was tall grass on the field). Upon inspection, it turns out that the cause of the fall was the leading edge of the wing breaking at the base of the wing (nothing else was damaged from the fall; in general, the model is surprisingly strong). The repair of a breakdown is simple - the remaining part in the slide is removed with pliers, and the remaining carbon rod is inserted in its place and fixed with cyacrine. To keep the wing tissue taut, the broken part (about 25mm) is extended at the end of the wing with a plastic tube of suitable diameter. I used a piece of refill from a gel fountain pen and pressed it onto the edge, its diameter was 3 mm.
The small shoulder by which the drive “pulls” the wing leads to greater forces on breaking the edge at the point where it exits the wing of the flapping mechanism, and the edge breaks at this point. This occurs under sudden load, usually during sudden “altitude” maneuvers.
I corrected this drawback by redoing the drawstring - making it twice as long. Although in my homemade design, not 3mm carbon rods were used as edges, but carbon tubes 6mm in diameter, steel rods with a diameter of 3mm were inserted into their base (at the rocker), these rods also broke after several flights. After reworking the wings, the breakdowns stopped, although I still couldn’t get the “bird” to turn its hinges...
Overall, the model makes a very good impression, is easy to assemble, flies very well (for a flywheel), and most importantly, it looks very cool (well, there’s no other way to say it!) looks in the air! The "Bird" is very easy to control, and even beginners can fly it. Almost indestructible design. Somehow, while flying at a stadium, after crashing from a direct flight into a lattice metal structure at a height of about 3 meters and subsequent falling onto the asphalt, nothing broke in the model!