Man will fly, relying not on the strength of his muscles, but on the strength of his mind.
(N. E. Zhukovsky)
Why and how an airplane flies Why can birds fly even though they are heavier than air? What forces lift a huge passenger plane that can fly faster, higher and farther than any bird, because its wings are motionless? Why can a glider that does not have a motor soar in the air? All these and many other questions are answered by aerodynamics - a science that studies the laws of interaction of air with bodies moving in it.
In the development of aerodynamics in our country, an outstanding role was played by Professor Nikolai Egorovich Zhukovsky (1847 -1921) - "the father of Russian aviation", as V. I. Lenin called him. Zhukovsky's merit lies in the fact that he was the first to explain the formation of the lift force of a wing and formulated a theorem for calculating this force. Zhukovsky not only discovered the laws underlying the theory of flight, but also paved the way for the rapid development of aviation in our country.
When flying on any aircraft there are four forces, the combination of which does not allow him to fall:
Gravity is the constant force that pulls the plane toward the ground.
Traction force, which comes from the engine and moves the aircraft forward.
Resistance force, opposite to the force of thrust and is caused by friction, slowing down the aircraft and reducing the lift of the wings.
lifting force, which is formed when the air moving over the wing creates a reduced pressure. Obeying the laws of aerodynamics, all aircraft rise into the air, starting with light sports aircraft
All aircraft at first glance are very similar, but if you look closely, you can find differences in them. They may differ in wings, tail, fuselage structure. Their speed, flight altitude, and other maneuvers depend on this. And each plane has only its own pair of wings.
To fly, you don't need to flap your wings, you need to make them move relative to the air. And for this, the wing just needs to be informed horizontal speed. From the interaction of the wing with the air, lift will arise, and as soon as its value is greater than the weight of the wing itself and everything connected with it, the flight will begin. The matter remains small: to make a suitable wing and be able to accelerate it to the required speed.
Observant people noticed a long time ago that birds have wings that are not flat. Consider a wing whose bottom surface is flat and its top surface is convex.
The air flow on the leading edge of the wing is divided into two parts: one flows around the wing from below, the other - from above. From above, the air has to go a little longer than from below, therefore, from above, the air speed will also be slightly greater than from below. It is known that as the velocity increases, the pressure in the gas flow decreases. Here, too, the air pressure under the wing is higher than above it. The pressure difference is directed upwards, that's the lifting force. And if you add the angle of attack, then the lifting force will increase even more.
How does a real plane fly?
A real airplane wing is teardrop shaped, which means that the air passing over the top of the wing moves faster than the air passing through the bottom of the wing. This difference in air currents creates lift and the plane flies.
And the fundamental idea here is this: the air flow is cut in two by the leading edge of the wing, and part of it flows around the wing along the upper surface, and the second part along the lower. In order for the two streams to converge behind the trailing edge of the wing without creating a vacuum, the air flowing around the upper surface of the wing must move faster relative to the aircraft than the air flowing around the lower surface, since it has to travel a greater distance.
Low pressure from above pulls the wing in, while higher pressure from below pushes it up. The wing goes up. And if the lifting force exceeds the weight of the aircraft, then the aircraft itself hangs in the air.
At paper planes no profile wings, so how do they fly? Lift is created by the angle of attack of their flat wings. Even with flat wings, you can see that the air moving over the wing travels a slightly longer distance (and moves faster). Lift is created by the same pressure as profile wings, but of course this difference in pressure is not so great.
The angle of attack of the aircraft is the angle between the direction of the speed of the air flow on the body and the characteristic longitudinal direction chosen on the body, for example, for an aircraft it will be the chord of the wing, it is the longitudinal construction axis, for a projectile or rocket it is their axis of symmetry.
straight wing
The advantage of a straight wing is its high lift coefficient, which allows you to significantly increase the specific load on the wing, and therefore reduce the size and weight without fear of a significant increase in takeoff and landing speed.
The disadvantage that predetermines the unsuitability of such a wing at supersonic flight speeds is a sharp increase in the drag of the aircraft.
delta wing
A delta wing is stiffer and lighter than a straight wing and is most often used at supersonic speeds. The use of a delta wing is determined mainly by strength and design considerations. The disadvantages of the delta wing are the emergence and development of a wave crisis.
CONCLUSION
If the shape of the wing and nose of a paper airplane is changed during modeling, then the range and duration of its flight may change.
Wings paper plane- flat. In order to provide a difference in air flow from above and below the wing (in order to form lift), it must be tilted to a certain angle (angle of attack).
Planes for the longest flights are not rigid, but they have a large wingspan and are well balanced.
1. Introduction. Objective. General patterns of development of the field of knowledge. The choice of the object of study. mindmap.
2. Elementary physics of glider flight (BS). System of force equations.
9. Photographs of the aerodynamic overview of the characteristics of the tube, aerodynamic balance.
10. Results of experiments.
12. Some results on the visualization of vortices.
13. Relationship between parameters and design solutions. Comparison of options reduced to a rectangular wing. The position of the aerodynamic center and the center of gravity and the characteristics of the models.
14. Energy efficient planning. flight stabilization. World record tactic for flight duration.
18. Conclusion.
19. List of references.
1. Introduction. Objective. General patterns of development of the field of knowledge. The choice of the object of research. mindmap.
The development of modern physics, primarily in its experimental part, and especially in applied fields, proceeds according to a pronounced hierarchical pattern. This is due to the need for an additional concentration of resources necessary to achieve results, from the material support of experiments to the distribution of work among specialized scientific institutes. Regardless of whether it is carried out on behalf of the state, commercial structures or even enthusiasts, but the planning of the development of the field of knowledge, the management of scientific research is a modern reality.
The purpose of this work is not only to set up a local experiment, but also an attempt to illustrate modern technology scientific organization at its simplest level.
The first reflections preceding the actual work are usually fixed in free form, historically this happens on napkins. However, in modern science, this form of presentation is called mind mapping - literally “thinking scheme”. It is a scheme in which everything fits in the form of geometric shapes. which may be relevant to the issue at hand. These concepts are connected by arrows indicating logical connections. At first, such a scheme may contain completely different and unequal concepts that are difficult to combine into a classical plan. However, this diversity allows you to find a place for random guesses and unsystematized information.
A paper airplane was chosen as the object of research - a thing familiar to everyone since childhood. It was assumed that the performance of a number of experiments and the application of the concepts of elementary physics would help explain the features of flight, and also, perhaps, make it possible to formulate general principles construction.
The preliminary collection of information showed that the area is not as simple as it seemed at first. Of great help was the research of Ken Blackburn, an aerospace engineer, holder of four world records (including the current one) for planning time, which he set with airplanes of his own design.
With regard to the task, the mind map looks like this:
This is a basic outline that represents the intended structure of the study.
2. Elementary physics of glider flight. System of equations for weights.
Planning - special case aircraft descent without the participation of thrust generated by the engine. For non-powered aircraft - gliders, as a special case - paper airplanes, gliding is the main flight mode.
Gliding is carried out due to weights balancing each other and aerodynamic force, which in turn consists of lift and drag forces.
The vector diagram of the forces acting on the aircraft (glider) during flight is as follows:
The condition for straightforward planning is the equality
The condition for planning uniformity is equality
Thus, to maintain rectilinear uniform planning, both equalities are required, the system
Y=GcosA
Q=GsinA
3. Delving into the basic theory of aerodynamics. laminar and turbulent. Reynolds number.
A more detailed understanding of flight is given by modern aerodynamic theory, based on the description of the behavior different types air flows, depending on the nature of the interaction of molecules. There are two main types of flows - laminar, when the particles move along smooth and parallel curves, and turbulent, when they are mixed. As a rule, there are no situations with ideally laminar or purely turbulent flow, the interaction of both of them creates a real picture of the operation of the wing.
If we consider a specific object with finite characteristics - mass, geometric dimensions, then the flow properties at the level of molecular interaction are characterized by the Reynolds number, which gives a relative value and denotes the ratio of force impulses to fluid viscosity. How more number, the less the influence of viscosity.
Re=VLρ/η=VL/ν
V (speed)
L (size characteristic)
ν (coefficient (density/viscosity)) = 0.000014 m^2/s for air at normal temperature.
For a paper airplane, the Reynolds number is about 37,000.
Since the Reynolds number is much lower than in real aircraft, this means that the viscosity of the air plays a much larger role, resulting in increased drag and reduced lift.
4. How conventional and flat wings work.
A flat wing from the point of view of elementary physics is a plate located at an angle to a moving air stream. The air is "thrown" at an angle downwards, creating an oppositely directed force. This is the total aerodynamic force, which can be represented as two forces - lift and drag. Such an interaction is easily explained on the basis of Newton's third law. A classic example of a flat reflector wing is a kite.
The behavior of a conventional (plano-convex) aerodynamic surface is explained by classical aerodynamics as the appearance of a lifting force due to the difference in the speeds of the flow fragments and, accordingly, the difference in pressures from below and above the wing.
A flat paper wing in the flow creates a vortex zone on top, which is like a curved profile. It is less stable and efficient than a hard shell, but the mechanism is the same.
The figure is taken from the source (See references). It shows the formation of an airfoil due to turbulence on the upper surface of the wing. There is also the concept of a transition layer, in which the turbulent flow becomes laminar due to the interaction of air layers. Above the wing of a paper airplane, it is up to 1 centimeter.
5. Overview of three aircraft designs
Three different designs of paper planes with different characteristics were chosen for the experiment.
Model No. 1. The most common and well-known design. As a rule, the majority imagines it when they hear the expression “paper plane”.
Model number 2. "Arrow", or "Spear". A characteristic model with a sharp wing angle and an assumed high speed.
Model number 3. Model with high aspect ratio wing. Special design, assembled on the wide side of the sheet. It is assumed that she has good aerodynamic data due to the high aspect ratio wing.
All planes were assembled from the same sheets of paper with a specific gravity of 80 grams / m ^ 2 A4 format. The mass of each aircraft is 5 grams.
6. Feature sets, why they are.
To obtain characteristic parameters for each design, it is necessary to determine these parameters themselves. The mass of all aircraft is the same - 5 grams. It is quite easy to measure the planning speed for each structure and angle. The ratio of the height difference and the corresponding range will give us the lift-to-drag ratio, essentially the same glide angle.
Of interest is the measurement of the lift and drag forces at different angles of attack of the wing, the nature of their changes in the boundary regimes. This will allow to characterize the structures on the basis of numerical parameters.
Separately, it is possible to analyze the geometric parameters of paper planes - the position of the aerodynamic center and the center of gravity for different wing shapes.
By visualizing flows, you can achieve a visual representation of the processes occurring in boundary layers air near the aerodynamic surfaces.
7. Preliminary experiments (chamber). Obtained values for speed and lift-to-drag ratio.
To determine the basic parameters, it was done the simplest experiment- the flight of a paper airplane was recorded by a video camera against the background of a wall with metric markings. Since the frame interval for video shooting (1/30 second) is known, the gliding speed can be easily calculated. According to the drop in altitude, the glide angle and the aerodynamic quality of the aircraft are found on the corresponding frames.
On average, the speed of the airplane is 5-6 m / s, which is not so little.
Aerodynamic quality - about 8.
8. Requirements for the experiment, Engineering task.
To recreate flight conditions, we need laminar flow up to 8 m/s and the ability to measure lift and drag. The classic method of aerodynamic research is the wind tunnel. In our case, the situation is simplified by the fact that the airplane itself is small in size and speed and can be directly placed in a tube of limited dimensions.
Therefore, we are not hindered by the situation when the blown model differs significantly in dimensions from the original, which, due to the difference in Reynolds numbers, requires compensation during measurements.
With a pipe section of 300x200 mm and a flow rate of up to 8 m / s, we need a fan with a capacity of at least 1000 cubic meters / hour. To change the flow rate, an engine speed controller is needed, and for measurement, an anemometer with appropriate accuracy. The velocity meter does not have to be digital, it is quite possible to get by with a deflected plate with angle graduations or a liquid anemometer, which has greater accuracy.
The wind tunnel has been known for a long time, Mozhaisky used it in research, and Tsiolkovsky and Zhukovsky have already developed it in detail modern technology experiment, which has not fundamentally changed.
To measure the drag force and lift force, aerodynamic balances are used, which make it possible to determine the forces in several directions (in our case, in two).
9. Photographs of the wind tunnel. Overview of pipe characteristics, aerodynamic balance.
The desktop wind tunnel was implemented on the basis of a sufficiently powerful industrial fan. Mutually perpendicular plates are located behind the fan, which straighten the flow before entering the measuring chamber. The windows in the measuring chamber are equipped with glass. A rectangular hole for holders is cut in the bottom wall. Directly in the measuring chamber, a digital anemometer impeller is installed to measure the flow velocity. The pipe has a slight constriction at the exit to “boost” the flow, which reduces turbulence at the expense of speed reduction. The fan speed is controlled by a simple household electronic controller.
The characteristics of the pipe turned out to be worse than the calculated ones, mainly due to the discrepancy between the fan performance and the passport characteristics. The flow boost also reduced the velocity in the measurement zone by 0.5 m/s. As a result maximum speed- slightly above 5 m / s, which, nevertheless, turned out to be sufficient.
Reynolds number for pipe:
Re = VLρ/η = VL/ν
V (speed) = 5m/s
L (characteristic) = 250mm = 0.25m
ν (factor (density/viscosity)) = 0.000014 m2/s
Re = 1.25/ 0.000014 = 89285.7143
To measure the forces acting on the aircraft, elementary aerodynamic balances with two degrees of freedom based on a pair of electronic jewelry scales with an accuracy of 0.01 gram were used. The aircraft was fixed on two racks at the right angle and mounted on the platform of the first scales. Those, in turn, were placed on a movable platform with a lever transmission of horizontal force to the second scales.
Measurements have shown that the accuracy is quite sufficient for basic modes. However, it was difficult to fix the angle, so it is better to develop an appropriate mounting scheme with markings.
10. Results of experiments.
When purging the models, two main parameters were measured - the drag force and the lifting force, depending on the flow velocity at given angle. A family of characteristics was constructed with sufficiently realistic values to describe the behavior of each aircraft. The results are summarized in graphs with further normalization of the scale relative to the speed.
11. Relationships of curves for three models.
Model No. 1.
Golden mean. The design corresponds to the material - paper. The strength of the wings corresponds to the length, the weight distribution is optimal, so a properly folded aircraft is well aligned and flies smoothly. It is the combination of such qualities and ease of assembly that made this design so popular. The speed is less than the second model, but more than the third. At high speeds, the wide tail is already beginning to interfere, which previously perfectly stabilized the model.
Model number 2.
Model with the worst flight characteristics. Large sweep and short wings are designed to work better on high speeds, which happens, but the lift does not grow enough and the plane really flies like a spear. In addition, it does not stabilize in flight properly.
Model number 3.
The representative of the "engineering" school - the model was conceived with special characteristics. High aspect ratio wings do work better, but the drag increases very quickly - the plane flies slowly and does not tolerate acceleration. To compensate for the lack of rigidity of the paper, numerous folds in the toe of the wing are used, which also increases the resistance. Nevertheless, the model is very revealing and flies well.
12. Some results on the visualization of vortices
If you introduce a source of smoke into the stream, you can see and photograph the streams that go around the wing. We did not have special smoke generators at our disposal, we used incense sticks. To increase the contrast, a special filter for photo processing was used. The flow rate also decreased because the density of the smoke was low.
Flow formation at the leading edge of the wing.
Turbulent tail.
Also, the flows can be examined using short threads glued to the wing, or with a thin probe with a thread at the end.
13. Relationship between parameters and design solutions. Comparison of options reduced to a rectangular wing. The position of the aerodynamic center and the center of gravity and the characteristics of the models.
It has already been noted that paper as a material has many limitations. For low flight speeds, long narrow wings have best quality. It is no coincidence that real gliders, especially record holders, also have such wings. However, paper planes have technological limitations and their wings are not optimal.
To analyze the relationship between the geometry of models and their flight characteristics, it is necessary to bring a complex shape to a rectangular analogue by the area transfer method. Best deal with it computer programs, allowing you to represent different models in universal form. After the transformations, the description will be reduced to the basic parameters - span, chord length, aerodynamic center.
The interconnection of these quantities and the center of mass will make it possible to fix the characteristic values for various types behavior. These calculations are beyond the scope of this work, but can be easily done. However, it can be assumed that the center of gravity for a paper plane with rectangular wings is at a distance of one to four from nose to tail, for an aircraft with delta wings - at one second (the so-called neutral point).
14. Energy efficient planning. flight stabilization.
World record tactic for flight duration time.
Based on the curves for lift and drag, one can find an energetically favorable flight mode with the least losses. This is certainly important for long-range liners, but it can also come in handy in paper aviation. By slightly modernizing the airplane (bending edges, redistributing weight), you can achieve better flight characteristics or, conversely, transfer the flight to a critical mode.
Generally speaking, paper planes do not change characteristics during flight, so they can do without special stabilizers. The tail, which creates resistance, allows you to shift the center of gravity forward. Straightness of flight is maintained due to the vertical plane of the fold and due to the transverse V of the wings.
Stability means that the aircraft, when deflected, tends to return to a neutral position. The point of glide angle stability is that the aircraft will maintain the same speed. The more stable the aircraft, the more speed same as model #2. But, this trend needs to be curtailed - lift must be used, so the best paper planes, for the most part, have neutral stability, this is the best combination of qualities.
However, the established regimes are not always the best. The world record for the longest flight was set with a very specific tactic. Firstly, the start of the airplane is carried out in a vertical straight line, it is simply thrown onto maximum height. Secondly, after stabilization at the top point due to the relative position of the center of gravity and the effective wing area, the airplane must itself go into normal flight. Thirdly, the weight distribution of the airplane is not normal - it has an underloaded front part, therefore, due to the large resistance that does not compensate for the weight, it slows down very quickly. At the same time, the lifting force of the wing drops sharply, it nods down and, falling, accelerates with a jerk, but again slows down and freezes. Such oscillations (cabration) are smoothed out due to inertia at the fading points and, as a result, the total time spent in the air is longer than normal uniform glide.
15. A little about the synthesis of a structure with given characteristics.
It is assumed that having determined the main parameters of a paper plane, their relationship, and thus completing the analysis stage, it is possible to proceed to the synthesis problem - based on necessary requirements create a new structure. Empirically, amateurs all over the world do this, the number of designs has exceeded 1000. But there is no final numerical expression for such work, just as there are no special obstacles to doing such research.
16. Practical analogies. Flying squirrel. Wing suite.
It is clear that a paper airplane is, first of all, just a source of joy and a wonderful illustration for the first step into the sky. A similar principle of soaring is used in practice only by flying squirrels, which are not of great economic importance, at least in our lane.
A more practical equivalent of a paper plane is the "Wing suite" - a wingsuit for skydivers that allows horizontal flight. By the way, the aerodynamic quality of such a suit is less than that of a paper plane - no more than 3.
17. Return to the mind map. The level of development. Emerged questions and options for further development of research.
Taking into account the work done, we can apply a coloring on the mind map indicating the completion of the tasks. Green color here indicates points that are at a satisfactory level, light green - issues that have some limitations, yellow - areas affected, but not developed to the extent necessary, red - promising, in need of additional research.
18. Conclusion.
As a result of the work, the theoretical base of the flight of paper planes was studied, experiments were planned and carried out, which made it possible to determine the numerical parameters for different designs and the general relationships between them. The complex mechanisms of flight are also affected, from the point of view of modern aerodynamics.
The main parameters affecting the flight are described, comprehensive recommendations are given.
In the general part, an attempt was made to systematize the field of knowledge based on the mind map, and the main directions for further research were outlined.
19. List of references.
1. Paper plane aerodynamics [Electronic resource] / Ken Blackburn - access mode: http://www.paperplane.org/paero.htm, free. - Zagl. from the screen. - Yaz. English
2. To Schütt. Introduction to the physics of flight. Translation by G.A. Wolpert from the fifth German edition. - M.: United Scientific and Technical Publishing House of the USSR NKTP. Edition of technical and theoretical literature, 1938. - 208 p.
3. Stakhursky A. For skillful hands: Desktop wind tunnel. Central Station for Young Technicians named after N.M. Shvernik - M .: Ministry of Culture of the USSR. Main Directorate of the Printing Industry, 13th Printing House, 1956. - 8 p.
4. Merzlikin V. Radio-controlled models of gliders. - M: Publishing house DOSAAF USSR, 1982. - 160 p.
5. A.L. Stasenko. Flight physics. - M: Science. Main edition of physical and mathematical literature, 1988, - 144 p.
In order to make a paper airplane, you will need a rectangular paper sheet, which can be either white or colored. If desired, you can use notebook, xerox, newsprint or any other paper that is available.
It is better to choose the density of the basis for the future aircraft closer to the average, so that it flies far and at the same time it is not too difficult to fold it (it is usually difficult to fix the folds on too thick paper and they turn out uneven).
It is better for novice origami lovers to start with the simplest airplane model familiar to everyone since childhood:
For those who failed to fold the plane according to the instructions, here is a video tutorial:
If you got tired of this option at school and you want to expand your paper aircraft building skills, we will tell you how to step by step perform two simple variations of the previous model.
Step by step photo instruction
Folding scheme
Do you want to learn how to properly launch a paper plane that you just made with your own hands? Then carefully read the rules of its management:
If all the rules are followed, but the model still does not fly as you would like, try improving it as follows:
We also bring to your attention a video instruction for the manufacture and testing of an interesting model of an aircraft that is capable of not only far, but also an incredibly long flight:
Now that you are confident in your abilities and have already got your hands on folding and launching simple airplanes, we offer instructions that will tell you how to make a more complex paper airplane.
Execution scheme
Step-by-step execution scheme
The paper fighter is ready!
Manufacturing instructions:
Following the given photo and video instructions, you can make a paper airplane with your own hands in a few minutes, playing with which will become a pleasant and entertaining pastime for you and your children!
Incredible Facts
Many of us have seen, or maybe made, paper airplanes and launched them, watching them soar in the air.
Have you ever wondered who was the first to create a paper plane and why?
Today, paper planes are made not only by children, but also by serious aircraft manufacturing companies - engineers and designers.
How, when and for what paper airplanes were used and are still used, you can find out here.
* The first paper airplane was created about 2,000 years ago. It is believed that the first who came up with the idea of making paper airplanes were the Chinese, who were also fond of creating flying kites from papyrus.
* The Montgolfier brothers, Joseph-Michel and Jacques-Etienne, also decided to use paper for flying. They are the ones who invented Balloon and used paper for it. It happened in the 18th century.
* Leonardo da Vinci wrote about using paper to create ornithopter (aircraft) models.
* In the early 20th century, aircraft magazines used images of paper airplanes to explain the principles of aerodynamics.
See also: How to make a paper airplane
* In their quest to build the first human-carrying aircraft, the Wright brothers used paper planes and wings in wind tunnels.
* In the 1930s, the English artist and engineer Wallis Rigby designed his first paper airplane. This idea seemed interesting to several publishers, who began to cooperate with him and publish his paper models, which were quite easy to assemble. It is worth noting that Rigby tried to make not just interesting models, but also flying ones.
* Also in the early 1930s, Jack Northrop of the Lockheed Corporation used several paper models of airplanes and wings for testing purposes. This was done before the creation of real large aircraft.
* During World War II, many governments restricted the use of materials such as plastic, metal and wood as they were considered strategically important. Paper has become commonplace and very popular in the toy industry. This is what made paper modeling popular.
* In the USSR, paper modeling was also very popular. In 1959, P. L. Anokhin's book "Paper Flying Models" was published. As a result, this book became very popular among modellers for many years. In it, one could learn about the history of aircraft construction, as well as paper modeling. All paper models were original, for example, one could find a flying paper model of the Yak aircraft.
*According to the Paper Aircraft Association, an EVA-launched paper airplane will not fly, it will glide in a straight line. If a paper airplane does not collide with some object, it can soar forever in space.
* The most expensive paper plane was used in the space shuttle during the next flight into space. The cost of the fuel used to get the plane into space on the shuttle alone is enough to call this paper plane the most expensive.
* The largest wingspan of a paper airplane is 12.22 cm. An airplane with such wings could fly almost 35 meters before hitting the wall. Such an aircraft was made by a group of students from the Faculty of Aviation and Rocket Engineering at the Polytechnic Institute in Delft, the Netherlands.
The launch was carried out in 1995, when the aircraft was launched inside the building from a platform 3 meters high. According to the rules, the plane had to fly about 15 meters. If not for the limited space, he would have flown much farther.
* Scientists, engineers and students use paper airplanes to study aerodynamics. National Aeronautics and Research Administration outer space(NASA) sent a paper airplane into space on the Space Shuttle.
* Paper planes can be made various forms. According to record holder Ken Blackburn, airplanes made in the shape of an "X," a hoop or a futuristic spaceship can fly just like simple paper airplanes if done right.
* NASA specialists together with astronauts held a master class for schoolchildrenin his hangar research center in 1992. Together they built large paper planes with a wingspan of up to 9 meters.
* The smallest paper origami airplane was created under a microscope by Mr. Naito from Japan. He folded an airplane from a sheet of paper measuring 2.9 square meters. millimeter. Once made, the airplane was placed on the tip of a sewing needle.
* The longest flight of a paper plane took place on December 19, 2010, and it was launched by the Japanese Takuo Toda, who is the head of the Japan Origami Airplane Association. The flight duration of his model, launched in the city of Fukuyama, Hiroshima Prefecture, was 29.2 seconds.
How to make a Takuo Toda airplane
Robot assembles a paper plane
Panaiotov Georgy
Objective: Design aircraft with the following characteristics: maximum range and flight duration.
Tasks:
Analyze information obtained from primary sources;
To study the elements of the ancient oriental art of aerogami;
To get acquainted with the basics of aerodynamics, the technology of designing aircraft from paper;
Test the constructed models;
Develop skills for the correct, effective launch of models;
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Research work "Investigation of the flying properties of various models of paper aircraft"
Hypothesis: It can be assumed that the flight characteristics of an aircraft depend on its shape.
Experiment No. 1 “The principle of creating a wing” The air moving along the upper surface of the strip exerts less pressure than the still air under the strip. He lifts the strip up.
Experiment No. 2 Moving air exerts less pressure than stationary air, which is under the sheet.
Experiment No. 3 "Blow" The still air at the edges of the strips exerts more pressure than the moving air between them. The pressure difference pushes the strips towards each other.
Trials: Model #1 Trial Range #1 6m 40cm #2 10m 45cm #3 8m
Trials: Model #2 Trial Range #1 10m 20cm #2 14m #3 16m 90cm
Trials: Model #3 Trial Range #1 13m 50cm #2 12m #3 13m
Trials: Model #4 Trial Range #1 13m 60cm #2 19m 70cm #3 21m 60cm
Trials: Model #5 Trial Range #1 9m 20cm #2 13m 20cm #3 10m 60cm
Test Results: Range Champion Model #4 Airtime Champion Model #5
Conclusion: The flight characteristics of an aircraft depend on its shape.
Introduction
Every time I see an airplane - a silver bird soaring into the sky - I admire the power with which it easily overcomes the earth's gravity and plows the heavenly ocean and ask myself questions:
Man has always dreamed of rising into the sky “like a bird” and since ancient times he has tried to make his dream come true. In the 20th century, aviation began to develop so rapidly that mankind could not save many of the originals of this complex technology. But many samples have been preserved in museums in the form of reduced models, giving an almost complete picture of real machines.
I chose this topic because it helps in life not only to develop logical technical thinking, but also to join the practical skills of working with paper, materials science, technology for designing and constructing aircraft. And the most important thing is the creation of your own aircraft.
We hypothesized - it can be assumed that the flight characteristics of the aircraft depend on its shape.
We used the following research methods:
Objective: Design aircraft with the following characteristics: maximum range and flight duration.
Tasks:
Analyze information obtained from primary sources;
To study the elements of the ancient oriental art of aerogami;
To get acquainted with the basics of aerodynamics, the technology of designing aircraft from paper;
Test the constructed models;
Develop skills for the correct, effective launch of models;
As the basis of my research, I took one of the areas of Japanese origami art - aerogami (from Japanese “gami” - paper and Latin “aero” - air).
Aerodynamics (from the Greek words aer - air and dinamis - force) is the science of the forces that arise when bodies move in the air. Air, thanks to its physical properties, resists advancing in it solids. At the same time, interaction forces arise between bodies and air, which are studied by aerodynamics.
Aerodynamics is theoretical basis modern aviation. Any aircraft flies, obeying the laws of aerodynamics. Therefore, for an aircraft designer, knowledge of the basic laws of aerodynamics is not only useful, but simply necessary. While studying the laws of aerodynamics, I conducted a series of observations and experiments: “The choice of the shape aircraft”, “Principles of creating a wing”, “Blow”, etc.
Design.
Folding a paper airplane is not as easy as it seems. Actions must be confident and precise, folds - perfectly straight and in the right places. Simple designs are forgiving, while in complex designs a couple of imperfect angles can lead the assembly process to a dead end. In addition, there are cases where the fold needs to be intentionally not very accurate.
For example, if one of the last steps requires you to fold a thick sandwich structure in half, the fold will not work unless you make a thickness adjustment at the very beginning of the fold. Such things are not described in diagrams, they come with experience. And the symmetry and precise weight distribution of the model determine how well it will fly.
The key point in "paper aviation" is the location of the center of gravity. By creating various designs, I propose to make the nose of the aircraft heavier by placing more paper in it, to form full-fledged wings, stabilizers, and a keel. Then paper airplane can be controlled like a real one.
For example, through experimentation, I found that the speed and flight path can be adjusted by bending the back of the wings like real flaps, slightly turning the paper keel. Such control is the basis of "paper aerobatics".
Aircraft designs vary significantly depending on the purpose of their construction. For example, aircraft for long-distance flights resemble a dart in shape - they are just as narrow, long, rigid, with a pronounced shift in the center of gravity towards the nose. Planes for the longest flights are not rigid, but they have a large wingspan and are well balanced. Balancing is extremely important for street launched aircraft. They must maintain the correct position, despite the destabilizing fluctuations in the air. Indoor-launched aircraft benefit from a nose-down center of gravity. Such models fly faster and more stable, they are easier to launch.
Tests
In order to achieve high results at the start, you need to master correct technique throw.
Launching in the open air, in addition to additional problems (wind), creates additional advantages. Using updrafts of air, you can make the plane fly incredibly far and long. A strong updraft can be found, for example, near a large multi-storey building: hitting a wall, the wind changes direction to vertical. more friendly air cushion can be found on a sunny day in a car park. Dark asphalt gets very hot, and the hot air above it rises smoothly.
Main part
1.1 Observations and experiments
Observations
The choice of the form of the aircraft.(Annex 11)
