How and why do planes fly? How is the aircraft control structured in the horizontal and vertical planes? Like an airplane taxiing on the ground.

Answer from ALIEN[guru]
Bernouli effect - when the airplane moves, it cuts the atmosphere of this planet with its wings into a couple of laminar flows, one of which (lower) is denser, and it pushes the aircraft up

Answer from B and x p b[guru]
Hello!
There is such a concept - aerodynamic lift (see Fig.), Which occurs when any object moves in the air, if this object has a shape that facilitates this (wing, fuselage ...) - this is "peeped" by man from nature on the flight of birds ... At the same time, under the wing, the air pressure and density increase, and above the wing, they fall, which creates a lifting force directed upward. Accordingly, the higher the speed of the object (in this case, the aircraft), the higher the lift becomes, and when, at a sufficient speed of air movement, the lift becomes greater than the weight, then the aircraft goes up, that is, "takes off", and if less, then the plane "descends", in equilibrium - the flight goes horizontally. Thus, the flight of the aircraft, its movement, occurs due to the power of the engine, which pushes the aircraft forward, which creates the airspeed of the aircraft. In a glider, such a force pushing it forward is the weight of the glider itself, which causes the glider to "slide" along the air flow downward, and in the absence of ascending currents (which glider pilots are "looking for"), the glider inexorably decreases. The takeoff process of a modern aircraft is divided into certain stages. First, in the starting position, standing on the brakes, all engines are accelerated to full thrust. When it is reached, the brakes are released and the aircraft begins to "take off" along the runway (runway). When the speed has reached such that it is not too late to stop before the end of the runway, then this is the moment of "decision-making" (yes-no) and if the appropriate decision is made, either take-off (acceleration) continues, or braking begins on the runway. If acceleration continues, then when the air speed is reached, at which the aerodynamic lift begins to exceed the aircraft's own weight, the aircraft takes off from the runway and it already "flies", starting to gain altitude. All the best to you and feel free to fly by air, because when you are driving on the road in a car, the probability of death is about 100 times higher than when you fly by plane! Therefore, at the exit to the freeway from one of the American airbases, where the latest types of supersonic aircraft are tested, there has been a poster for many years: "Pilot! Attention! Danger! - Freeway ahead!"
All the best.

Answer from Wave[guru]
the flow velocity ABOVE the wing is lower than UNDER the wing (well, the wing profile is this) and it turns out that the air pressure from above is less than under the wing (Bernoulli's law). This pressure is directed upward and is called lift.
To create a stream over the wing, the plane scatters to this very stream. And the helicopter turns over itself with these very wings - it also creates a stream. Here.

Answer from ScrAll[guru]
The destruction of the upper surface of the wing leads to the worst consequences ...
The bottom surface is much less affected.
Conclusion - the wing works like a suction cup, or rather the air above the wing.
Look at military planes - everything is hung under the wing, and nothing over ...

Answer from Yoslan to planet Earth[guru]
Well done Stas Sokolov ....
Just did not write where the Stop-Crane is located ....)))

A few days ago I was asked another interesting question, which I decided to answer with an article.

I couldn't have come up with such a thing in my life, because many things in aviation already seem obvious. But a couple of days ago the question "flew in": why, in fact, the plane turns with the help of the roll, this is somehow strange!

Let's then today try to find out why the plane needs to bank in order to start turning to the side.

It all starts with the physics of flight.

An airplane is affected by four forces in the air: lift, gravity, drag, and thrust.

When the thrust is equal to the frontal resistance - the plane flies at a constant speed, there is no acceleration.

When the weight is equal to the lift and the plane was flying without changing the altitude, then the plane will continue to hold this altitude.

The plane flies without a roll, so the lift is directed straight up, everything is fine.

Now let's see what happens if you look from the other side and take the example of a ship in bank.

It turns out that we direct the lift to the side, now it "pushes" the plane not straight up, but up and to the left.

If we decompose it into its components, then we will see that we have a force that pulls the plane towards the roll, and plus all the same lift.

But at the same time, do not forget that our lifting force also slightly decreases, because we give part of the energy "to the side". That is why, when instructing the aircraft to roll, it is necessary to slightly raise the nose in order to compensate for this very decrease. Then the plane will hold altitude.

That is why the plane makes a roll to turn left or right.

The vertical stabilizer is not used. it will not provide the necessary force that is needed to turn. The plane will begin to slide and turn very slightly.

If you want to safely (and legally) fly an aircraft, you need to obtain a pilot's license. But if you think that one day you will find yourself in an emergency, or are just curious about how things work, the ability to fly an airplane can come in handy. This is not an easy task, and the complete guide will take several hundred pages. This article will help you understand what you will encounter on your first practice flights.

Steps

Introduction to the control system

Inspect the plane before boarding. It is important to inspect the aircraft prior to takeoff. This is a visual assessment of the aircraft to ensure that all parts of the aircraft are in working order. The instructor will give you a list of actions that you will need to perform both during the flight and before it starts. It is imperative to follow these guidelines. Below are the basic rules for inspecting an aircraft prior to flight.

• Check control surfaces. Remove control locks. Make sure that the ailerons, flaps, and rudder move smoothly out of the way.
• Inspect gas and oil tanks. Check that they are filled to the correct level. You need a dipstick to measure the fuel level. There is an oil dipstick in the engine compartment for measuring the oil level.
• Check fuel for contaminants. For this, a small amount of fuel is placed in a special glass container and the presence of water or dirt in the sample is monitored. An instructor will show you how to do this.
• Complete the allowable weight on board and airplane load distribution forms. This will prevent overloading the aircraft. Again, the instructor will explain how to do this.
• Check the aircraft body for chips, cracks, or other damage. Damage, especially to the propeller blades, can affect airplane behavior. Always check the condition of the propellers and air intakes before takeoff. Approach the propellers with caution. If the aircraft harness is damaged, the propeller may spontaneously rotate, resulting in serious or even fatal injury.
• Check emergency supplies. Of course, I don’t want to think about it, but you should always take into account the possibility of an accident. Check for food, water, first aid kit, walkie talkie, flashlight and batteries. You may also need weapons and standard parts for repairs.

1. Find a wheel. When you take your seat in the pilot's seat, you will see a complex control panel in front of you, but it will be easier for you to understand it once you understand what each device is responsible for. There will be a long steering wheel in front of you. This is the steering wheel.

   • The steering wheel serves the same role as the steering wheel in a car - it sets the position of the nose of the aircraft (up and down) and the tilt of the wings. Try to hold the steering wheel. Push it away from you, then pull it towards you, move it left and right. Don't pull too hard - small movements are enough.

2. Find a gas and a gas control device. These buttons are usually found between the seats in the cockpit. The gas button is black and the gas control button is usually red. In civil aviation, these control tools are usually in the form of conventional buttons.

   • The fuel intake is controlled by the gas button, and the second button is responsible for the control of the combustible mixture.

3. Find flight control tools. Most aircraft have six, and they are arranged horizontally in two rows. These instruments show altitude, aircraft attitude, course, and speed (both climb and descent).

   • Top left: airspeed indicator... It displays the ship's speed in knots. (A knot equals one nautical mile per hour, or approximately 1.85 km / h.)
   • Top middle: attitude indicator(artificial horizon). It shows the spatial position of the aircraft, that is, its angle of inclination up or down, left or right.
   • Top right: altimeter(altimeter). It shows the altitude above sea level.
   • Bottom left: direction indicator and slip... It is a combined instrument that shows the yaw of the aircraft, roll and slide angles about the longitudinal axis (if the plane is flying sideways).
   • Bottom middle: course pointer... It shows the current heading of the vessel. This instrument is calibrated (usually every 15 minutes) to match the compass. This is done on the ground or in the air, but only during flight in a straight line with constant altitude.
   • Bottom right: climb rate indicator... It shows how fast the plane is gaining or dropping altitude. Zero means the plane is flying at a constant altitude.

4. Find landing control tools. Many small planes have fixed gears, in which case there will be no gear lever for landing. If your aircraft is equipped with manual gear shifting, the corresponding lever can be in any position. Typically, this is a lever with a white handle. You will use it when taking off, landing and when the plane moves along the ground. In addition to performing other functions, this lever controls the landing gear, skis and floats of the aircraft.

   Place your feet on the steering pedals. You will have pedals under your feet that you can use to set the turn. They are attached to a vertical stabilizer. If you need to turn slightly to the left or right on the vertical axis, use the pedals. In fact, the pedals set the rotation about the vertical axis. They are also responsible for turning on the ground (many novice pilots assume that the direction of movement on the ground is given by the helm).

   Takeoff

   1. Obtain clearance to take off. If you are at an airport with a dispatcher, you need to contact the dispatcher before starting to move on the ground. You will be given all the information you need, including the transponder code. Write it down as this information will need to be repeated for the controller before you are cleared to take off. When cleared, proceed to the runway in accordance with the instructions of the ground crew. Never do not enter the runway without a take-off permit!

      Adjust the flaps for takeoff. As a rule, they should be at an angle of 10 degrees. Flaps create lift, which is why they are used during takeoff.

      Check the operation of the motors. Before entering the runway, stop in the engine check area and follow the appropriate check procedure. This will ensure that it is safe to take off.

      • Ask the instructor to show you how to check the engines.

   2. Tell the dispatcher that you are ready to take off. After a successful check of the engines, inform the dispatcher of readiness and wait for permission to continue on the runway.

   3. Press the mixture control button down as far as possible. Start gradually pushing the throttle button - the plane will accelerate. He will want to turn left, so hold him in the middle of the runway with the pedals.

      • If there is a crosswind, you will need to turn the helm slightly towards the wind. When you pick up speed, gradually return the helm to its original position.
      • Yaw (yaw) must be controlled using the pedals. If the plane starts to spin, use the pedals to level it.

   4. Accelerate. To get into the air, the plane needs to gain a certain speed. The throttle must be squeezed out to the end, and then the plane will begin to climb (usually for small planes take off speed is about 60 knots). The airspeed indicator will tell you when you reach that speed ..

      • When the necessary lift is generated, the nose of the aircraft will begin to lift off the ground. Pull the steering wheel to help the plane take off.

   5. Pull the steering wheel towards you. This will allow the aircraft to take off.

      • Remember to maintain the climb rate and the correct rudder position.
      • When the airplane has climbed sufficiently and when the climb rate indicator is positive (that is, the airplane is climbing), return the flaps and landing gear to neutral to reduce drag.

   Flight control

   1. Set up an artificial horizon, or attitude indicator. It will help you keep the plane level. If you go outside the desired values, pull the steering wheel towards you to raise the nose. Don't jerk too hard - it doesn't take much effort.

      • To keep the plane from deviating from the horizon, constantly check the attitude and altimeter readings. But remember that it is not worth looking at this or that sign for too long.

   2. Make a turn. This is also called performing a superelevation. If you have a wheel in front of you, turn it. If it looks like a handle, tilt it to the left or right. To avoid losing control, look at the direction indicator. This tool displays a picture of a small plane overlaid with a level with a black ball. You need to keep the black ball in the middle - adjust the position of the plane with the pedals, and then all your turns will be smooth and accurate.

      • To better remember which pedal to press, imagine that you are stepping on a ball.
      • Ailerons are responsible for the roll angle. They work in conjunction with the steering pedals. When turning, coordinate the pedals with the ailerons so that the tail stays behind the nose. Always keep an eye on altitude and airspeed.
        • When you turn the steering wheel to the left, the left aileron is raised and the right aileron is lowered. When turning right, the right aileron rises and the left aileron lowers. Do not think too much about how this happens in terms of mechanics and aerodynamics; you are now familiar with the basics.

   3. Control the speed of the plane. Each aircraft has engine settings optimized for the cruise flight mode. When you reach the desired altitude, change the settings so that the engine is running at 75% power. Adjust the settings for constant level flight. You will feel that all levers begin to move more smoothly. On some airplanes, these settings allow the airplane to be put into a non-torque mode, which does not require pedal control to keep the airplane in a straight line.

      • At 100% engine load, the nose shifts to the side due to the torque generated by the engine, which requires correction using the pedals, so in order to return the plane to the desired position, you have to direct it in the opposite direction.
      • In order for the aircraft to maintain its position in space, it is necessary to provide the necessary speed and air supply. If the plane flies too slowly or at a steep angle, it can lose the air flow it needs and freeze. This is especially dangerous during takeoff and landing, but speed should always be monitored.
      • As with driving a car, the more often you push the throttle to the floor, the more stress it puts on the engine. Step on the gas only if you need to pick up speed, and release the gas to descend without acceleration.

   4. Do not overuse control. During turbulence, it is important not to overdo it with adjustments, otherwise you can accidentally force the plane to operate at its maximum capacity, which will lead to equipment damage (in the event of severe turbulence).

      • Carburetor icing can be another problem. You will see a button labeled "carb heat". Run the heating for short periods of time (eg 10 minutes), especially in high humidity conditions that cause icing. (This only applies to aircraft with a carburetor.)
      • Do not shift your attention entirely to this task - you need to keep an eye on all the instruments and check for the presence of flying objects near your plane.

   5. Set the cruising engine speed. When the speed levels off, lock the controls in their current position so that the plane is constantly moving at the same speed and you can control the course. Reduce engine load by up to 75%. If you are flying a single engine Cessna, the recommended load is 2,400 rpm.

      • Install the trimmer. The trimmer is a small panel-mounted device that can be moved around in the cab. Correct trim setting will help prevent the rise or fall when cruising.
      • There are different types of trimmers. Some are in the form of a wheel or a lever, while others are a handle to pull or a rocking chair. There are also screw and cable trims. There are also electrical systems that are easiest to manage. The trim settings are tailored to the specific speeds that the airplane can handle. They usually depend on the weight, structure of the ship, center of gravity and weight of cargo and passengers.

A control device (roll rudders), which is equipped with conventional aircraft and created according to the "canard" scheme. Ailerons are placed on the trailing edge of the wing consoles. They are designed to control the angle of inclination of "iron birds": at the time of application, the roll rudders are deflected in opposite directions, differentially. In order for the plane to tilt to the right, the left aileron is directed down, and the right aileron up, and vice versa.

What is the principle of the roll rudders? Lift decreases at that part of the wing that is located in front of the aileron raised up. The part of the wing, which is located in front of the lowered aileron, increases the lift. Thus, a force moment is formed, which modifies the speed of rotation of the aircraft around an axis identical to the longitudinal axis of the machine.

Story

Where did the aileron first appear? This amazing device was installed on a monoplane created in 1902 by innovator Richard Percy of New Zealand. Unfortunately, his car made only very unstable and short flights. It turned out to be the 14 Bis, made by Alberto Santos-Dumont, which made an absolutely coordinated flight with the use of rudders. Previously, aerodynamic controls replaced the Wright brothers' wing distortion.

So, we study further the aileron. This device has many advantages. The control surface that aligns the flaps and rudders is called a flaperon. In order for the ailerons to mimic the function of the extended flaps, they are simultaneously lowered down. For long-term roll control, a simple differential turn is added to this deviation.

To adjust the inclination of the liners with the above-mentioned layout, the modified thrust vector of the engines, gas rudders, spoilers, rudder, transformation of the aircraft center of mass, differential displacement of high-altitude rudders and other tricks can also be used.

Side effects

How does the aileron work? This is a whimsical mechanism that has some disadvantages. One of the side effects of its action is a slight yaw in the opposite direction. In other words, when using the ailerons to turn to the right, the aircraft may move slightly to the left at the moment of roll increase. This effect appears due to the difference in drag between the left and right cantilevers caused by the change in lift when the ailerons oscillate.

The wing cantilever with the aileron deflected downward possesses a large drag coefficient. In current iron bird control systems, this side effect is mitigated in a variety of ways. For example, in order to create a roll, the ailerons are also displaced in the opposite direction, but at unequal angles.

Reverse effect

You must admit that flying an airplane requires skill. So, on high-speed cars with a significantly lengthened wing, the effect of reversing the roll rudders can be noticed. What does he look like?

If, when deflecting the aileron located close to the wingtip, a maneuverable load appears, the wing of the aircraft is inverted, and the angle of attack on it deviates. Such events can smooth out the effect of the aileron shift, or they can lead to the opposite result.

For example, if it is necessary to increase the lift of the wing, the aileron is deflected down. Further, the force directed upward begins to act on the trailing edge of the wing, the wing turns forward, and the angle of attack on it decreases, which reduces the lift. In fact, the effect of the roll rudders on the wing during reverse is similar to the effect of the trim tab.

One way or another, the reverse of the roll rudders was found on many jet aircraft (especially on the Tu-134). By the way, on the Tu-22, due to this effect, the limit was reduced to 1.4. In general, pilots study aileron control for a long time. The most common methods of preventing roll reversal are the use of spoiler ailerons (spoilers are located near the center of the wing chord and, when released, practically do not cause it to twist) or the installation of additional ailerons near the center section. If the second option is present, the external (located near the tips) rudders, necessary for productive control at low speeds, are turned off at high speeds, and lateral control is carried out due to the internal ailerons, which do not give reverse due to the impressive stiffness of the wing present in the center section area.

Control systems

Now let's take a look at airplane control. A group of on-board devices that guarantee the adjustment of the movement of "steel birds" is called a control system. Since the pilot is located in the cockpit, and the rudders and ailerons are located on the wings and tail of the aircraft, a constructive connection is established between them. Her responsibilities include ensuring the reliability, ease and efficiency of machine position control.

Of course, when the coordinating surfaces are displaced, the force affecting them increases. However, this should not lead to an unacceptable increase in voltage on the adjustment levers.

The aircraft control mode can be automatic, semi-automatic and manual. If a person with the help of muscular force makes piloting instruments work, then such a control system is called manual (direct regulation of the liner).

Manual systems can be hydromechanical or mechanical. In fact, we found out that the wing of an airplane plays an important role in control. On civil aircraft, basic adjustments are made by two pilots using force and displacement kinematics, double command levers, mechanical wiring and control surfaces.

If the pilot controls the machine with the help of mechanisms and devices that ensure and improve the quality of the piloting process, then the control system is called semi-automatic. Thanks to the automatic system, the pilot only controls a group of self-acting parts, which creates and modifies coordinating forces and factors.

Complex

The means of basic control of the liner is a complex of on-board devices and structures, with the help of which the pilot activates the means of adjustment that change the flight mode or balance the aircraft in a given mode. This includes rudders, ailerons, and an adjustable stabilizer. Elements that guarantee the adjustment of additional control parts (flaps, spoilers, slats) are called either auxiliary control.

The liner basic coordination system includes:

• the command levers that the pilot acts on by moving them and applying force to them;
• special and automatic devices;
• piloting harness connecting basic control systems to command levers.

Implementation of management

The pilot performs longitudinal control, that is, he changes the pitch angle by deflecting the steering column away from himself or towards himself. By turning the steering wheel to the left or right and deflecting the ailerons, the pilot implements lateral control, tilting the car in the desired direction. To move the rudder, the pilot presses on the pedals, which are also used to control the front landing gear while the aircraft is moving on the ground.

In general, the pilot is the main link in the manual and semi-automatic control systems, and the flaps, ailerons and other aircraft parts are just a method of movement. The pilot perceives and processes information about the position of the vehicle and rudders, the acting overloads, develops a solution and acts on the command levers.

Requirements

Basic aircraft control must meet the following requirements:

1. When controlling the machine, the movements of the legs and arms of the pilot, necessary for the displacement of the command levers, must coincide with the natural reflexes of a person, which appear when maintaining balance. Moving the command stick in the desired direction should cause the "steel bird" to move in the same direction.
2. The reaction of the liner to the displacement of the control levers should have a slight delay.
3. At the moment of deflection of control instruments (rudders, ailerons, etc.), the forces applied to the command levers should increase smoothly: they must be directed in the direction opposite to the movement of the handles, and the amount of labor must be coordinated with the flight mode of the machine. The latter helps the pilot to gain a "sense of control" of the aircraft.
4. The rudders must act independently of each other: deflection, for example, of the elevator cannot cause deflection of the ailerons, and vice versa.
5. The angles of displacement of the steering surfaces are required to ensure the likelihood of the machine flying in all required take-off and landing modes.

We hope this article helped you understand the purpose of the ailerons and understand the basic control of the "steel birds".

The aircraft belongs to the aircraft heavier than air. This means that certain conditions are required for its flight, a combination of precisely calculated factors. The flight of an airplane is the result of the action of the lift, which occurs when the air flows towards the wing. It is rotated at a precisely calculated angle and has an aerodynamic shape, due to which, at a certain speed, it begins to strive upward, as the pilots say - “stands in the air”.

Engines accelerate the plane and maintain its speed. Jet propellants push the plane forward due to the combustion of kerosene and a stream of gases escaping from the nozzle with great force. Propeller engines "pull" the plane along.

The wing of modern aircraft is a static structure and by itself cannot generate lift on its own. The ability to lift a multi-ton vehicle into the air occurs only after the forward movement (acceleration) of the aircraft using the power plant. In this case, the wing, placed at an acute angle to the direction of the air flow, creates a different pressure: it will be less above the iron plate, and more below the product. It is the pressure difference that gives rise to the aerodynamic force that contributes to the climb.

Aircraft lift consists of the following factors:

1. Angle of attack
2. Unsymmetrical wing profile

The inclination of the metal plate (wing) to the air flow is called the angle of attack. Usually, when the aircraft is lifting, the mentioned value does not exceed 3-5 °, which is sufficient for takeoff of most aircraft models. The fact is that the design of the wings has undergone major changes since the creation of the first aircraft and today it is an asymmetrical profile with a more convex top sheet of metal. The bottom sheet of the product is characterized by a flat surface for virtually unimpeded air flow.

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Schematically, the process of generating lift looks like this: the upper air jets need to travel a longer distance (due to the convex shape of the wing) than the lower ones, while the amount of air behind the plate should remain the same. As a result, the upper trickles will move faster, creating a region of reduced pressure according to the Bernoulli equation. The direct difference in pressure above and below the wing, coupled with the operation of the engines, helps the aircraft to gain the required altitude. It should be remembered that the value of the angle of attack should not exceed the critical mark, otherwise the lift will drop.

The wings and engines are not enough for a controlled, safe and comfortable flight. The plane needs to be steered, while precision control is most needed during landing. Pilots call a controlled fall landing - the speed of an airplane decreases so that it begins to lose altitude. At a certain speed, this fall can be very smooth, resulting in a soft touch of the landing gear wheels to the strip.

Controlling an airplane is completely different from driving a car. The pilot's steering wheel is designed to deflect up and down and create a roll. “On yourself” is a climb. “From myself” is a descent, a dive. In order to turn, change the course, you need to press one of the pedals and tilt the aircraft in the direction of the turn with the steering wheel ... By the way, in the language of pilots this is called “turn” or “turn”.

For turning and stabilizing the flight, a vertical keel is located in the tail of the aircraft. And the small “wings” under and above it are horizontal stabilizers that do not allow the huge machine to rise and fall uncontrollably. On the stabilizers for control there are movable planes - elevators.

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To control the engines, there are levers between the pilots' seats - during takeoff, they are shifted completely forward, to maximum thrust, this is the takeoff mode required to gain takeoff speed. When landing, the levers are pulled back completely - to the minimum thrust mode.

Many passengers watch with interest as the rear of the huge wing suddenly drops down before landing. These are flaps, wing “mechanization”, which performs several tasks. When descending, fully extended mechanization slows down the aircraft to prevent it from accelerating too much. When landing, when the speed is very low, the flaps create additional lift for a smooth loss of altitude. During takeoff, they help the main wing to keep the aircraft in the air.

What shouldn't you be afraid of in flight?

There are several moments of flight that can scare the passenger - these are turbulence, passing through clouds and clearly visible oscillations of the wing consoles. But this is not dangerous at all - the structure of the aircraft is designed for enormous loads, much more than those that arise during "bumpiness". Consoles shaking should be taken calmly - this is an allowable design flexibility, and flight in the clouds is provided by instruments.