the main page the main page the main page the main page

In flight!

the Science and technics
 
ru - ua - en - fr - by - de - es

the plane Invention - one of the largest achievements of the XX-th century. As a source of inspiration the person was served by supervision over the pilots created by the nature, - birds. For a long time the person passionately dreamt to learn to soar up in the sky with ease and grace of a bird. In the Ancient Greece there was a legend about Ikare which made wings from wax and feathers and have flied up in the sky.

The Great Italian artist and the inventor of Renaissance Leonardo da Vinci too was the tireless advocate of idea of mechanical flight. It has left set of drawings with the drawings of flying machines. But before the secret of flight has gradually started to reveal, has passed as early as four hundred years.


the Important opening

In 1738 the Swiss mathematician and doctor Daniel Bernulli has opened that the faster liquid or gas movement, the more low pressure. For example, at a meeting with a moving wing of a bird air is divided into two streams, going over a wing and under it. As the top surface covered is bent and, hence, is longer more flat bottom, air needs to pass bolshee distance. Therefore it moves with greater speed and faster loses pressure over a wing, thereby, increasing pressure under a wing and raising it upwards. It is called as a carrying power.

In a XIX-th century many pioneers of aeronautics used this principle at creation of primitive gliders. In 1853 George Kejli whom often name "ю=чюь рІЁюяырэр" has constructed and has tested the first-ever glider. Then, in 1890th, Americans brothers Right have designed a wing, allowed to make flight operated.

If to separate a wing from the case (fuselage) of the plane and to look at it in section, it becomes visible that under the form it reminds a drop lying on one side with the flattened basis. The wide and bent forward part (a forward edge), more flat and fenny back part (a back edge) - such form is called as an aerodynamic profile. It shows the law of Bernulli by creation of two air streams: over and under a wing.


whirlwind Formation

The Carrying power formed as a result of this action, increases at the expense of natural movement of air. Passing on a wing and rolling down from its back edge, the air stream forms a funnel, as the water which is flowing down in a drain aperture. Such turbulence is called an initial whirlwind. It, in turn, forms a counter whirlwind. On force it is equal initial, but rotates in the opposite direction, passes under a wing and meets the basic air stream, moving in an opposite direction. As a result movement of the basic air stream is slowed down.

The Counter whirlwind is formed on a forward edge of a wing before to merge with the basic stream of air. As a result the bottom stream of air is slowed down, and top is accelerated. Pressure upon a wing decreases, and under a wing raises, owing to what the carrying power increases.


Launch!

Now it was necessary to set somehow to the plane that speed which will create a demanded carrying power. Americans of Uilbur and Orvill Right have solved this problem, having constructed the small engine with extremely small weight. The engine put in action some propellers in the form of the aerodynamic profiles established in vertical position in a forward part of the plane. The movement of air created by this rotation, is called as draught. Draught forms the carrying power directed forward, pushing away air back and forcing the plane to move forward. Brothers Right have carried out the first-ever flight on a flying machine more hard air on December, 17th, 1903 in the city of Kitti-Hok, the State of North Carolina. Them "ИырщхЁ" was in air of only 12 seconds and has flown by only 36 metres, but, nevertheless, it was possible to show successfully fidelity of the principle taken as a principle all subsequent aircraft construction.


Modern engines

Modern engines In 1940th aviabuilders have created a turbojet creating force of draught by a compression of air in the middle chamber where it mixes up with a special kind of kerosene and is set fire. As a result of ignition exhaust gases which are thrown out from a back part of the engine are formed and push the plane forward.

Jet planes reach higher speed, than with propellernym the engine, but consume too much fuel, especially on lower speeds. Therefore the compromise turbo-propeller engine where jet draught is used for actuating of propellers has been created. More the wide circulation was received today by the turbofan engine. In its forward part it is located mnogolopastnyj a propeller forcing air in the chamber of combustion. Besides, it directs a stream of air round the basic cover of the engine and creates the force of draught pushing the plane forward. In a back part of the engine reversive devices which at inclusion direct air stream forward are located, sharply extinguishing speed of the plane.

There are six basic movements, carried out by plane during flight: launch, ascent, flight at the set height, turn, decrease and landing. These movements are regulated by a design of wings and the stabilizer which also are aerodynamic profiles and, accordingly, create a carrying power. At launch flaps on back edges of wings rise to increase the area of a surface and to create the big carrying power. On the stabilizer similar devices on the function - elevators also rise. Thus the plane nose rises upwards, the tail part falls, and the plane directs up. It is important, that the plane before performance of this maneuver has had time to gain the necessary speed. Flaps and elevators should rise precisely while the force of lifting directed upwards is equal to the force of weight of the plane directed downwards, differently engines will decay, draught and lifting will disappear becomes impossible.

There is also a problem of aerodynamic resistance. Plane progress creates resistance of air, moving in an opposite direction. Such braking force (resistance) is created by any moving body, but only planes face with so-called. It is artificial the created resistance. The part of the energy formed at passage of an air stream on a wing, is taken away back; she tries "ю==рЁш=і" the plane in an opposite side. It occurs partially from round the corner an inclination of a wing and partially owing to turbulence.

Additional aerodynamic resistance is created by whirlwinds on the wing end when the area of a high pressure from under a wing on a back edge partially merges with area of low pressure over a wing.

Aerodynamic resistance at ascent after launch is overcome at the expense of lowering of flaps. The plane is levelled, continuing to speed up, while draught will not exceed aerodynamic resistance; then flaps again rise also the plane gains the demanded height. The plane is ready to flight at the set height when forces of lifting and an attraction are equal, and draught is equal to resistance.


Turn

Plane Turn is made by means of one more kind of hinged flaps (eleronov), and also a wheel in a back part kilja.

Turn Elerony are located on a back edge of wings. If the pilot wishes to turn the plane to the left, it lowers elerony on an opposite wing, i.e. On right that leads to increase at this wing of a carrying power. Simultaneously rises eleron on the left wing, reducing a carrying power from this party. When after that the plane enters in the left bend, a wheel on kile turns to the left simultaneously with eleronami and finishes maneuver. The pilot turns all these devices in an opposite side to level wings, and returns them in a starting position when the plane has laid down on the necessary course. At decrease the pilot should conduct the plane directly towards to a wind as the counter stream of air facilitates management. The lateral wind will take down the plane aside.


Soft landing

To plant the plane, the pilot reduces speed and lowers flaps, inclining a plane nose forward. The Carrying power decreases, resistance increases, and the plane begins decrease. At approach to a runway (VPP) elevators on the stabilizer rise simultaneously with predkrylkami - one more element of mechanisation of the wing, located on its forward edge. It increases a surface covered and creates an additional carrying power. The plane nose rises upwards, and the tail part falls. Thereby loss of a carrying power owing to decrease in speed is compensated.

The Plane reduces speed, and from outside, apparently, that for a second it as though hangs over VPP. That the engine has not decayed, one more type of hinged guards on a forward edge is put in action. These "тючфѕ°э№х =юЁьючр" - intertseptory - create turbulence which raises aerodynamic resistance and brings to nothing a carrying power.


a plane Stop

The Plane lets out the chassis that raises resistance even more. The earths the basic chassis concern with the first, then elevators on the stabilizer fall, the nose bends downwards, and forward chassis concern VPP. Now the plane completely is on the earth. Engines are switched to reversive draught, and flaps fall to create the maximum resistance. Brakes join. The plane smoothly stops.