Tom how the plane works and what. How does an airplane work?

An airplane is an aircraft, without which today it is impossible to imagine the movement of people and cargo over long distances. The development of the design of a modern aircraft, as well as the creation of its individual elements, seems to be an important and responsible task. Only highly qualified engineers and specialized specialists are allowed to do this work, since a small error in calculations or a manufacturing defect will lead to fatal consequences for pilots and passengers. It is no secret that any aircraft has a fuselage, load-bearing wings, a power unit, a multi-directional control system and takeoff and landing devices.

The information below about the design features of aircraft components will be of interest to adults and children involved in the design development of models. aircraft, as well as individual elements.

Airplane fuselage

The main part of the aircraft is the fuselage. The remaining structural elements are attached to it: wings, tail with fins, landing gear, and inside there is a control cabin, technical communications, passengers, cargo and the crew of the aircraft. The aircraft body is assembled from longitudinal and transverse load-bearing elements, followed by metal sheathing (in light-engine versions - plywood or plastic).

When designing an aircraft fuselage, the requirements are for the weight of the structure and maximum strength characteristics. This can be achieved using the following principles:

1. The aircraft fuselage body is made in a shape that reduces drag on air masses and promotes the generation of lift. The volume and dimensions of the aircraft must be proportionally weighed;
2. When designing, the most dense arrangement of the skin and strength elements of the body is provided to increase the useful volume of the fuselage;
3. They focus on the simplicity and reliability of fastening wing segments, takeoff and landing equipment, and power plants;
4. Places for securing cargo, accommodating passengers, and consumables must ensure reliable fastening and balance of the aircraft under various operating conditions;

1. The location of the crew must provide conditions for comfortable control of the aircraft, access to basic navigation and control instruments in extreme situations;
2. During the period of aircraft maintenance, it is possible to freely diagnose and repair failed components and assemblies.

The strength of the aircraft body must be able to withstand loads under various flight conditions, including:

• loads at the attachment points of the main elements (wings, tail, landing gear) during takeoff and landing modes;
• during the flight period, withstand the aerodynamic load, taking into account the inertial forces of the aircraft’s weight, the operation of units, and the functioning of equipment;
• pressure drops in hermetically confined parts of the aircraft, constantly arising during flight overloads.

The main types of aircraft body construction include flat, one- and two-story, wide and narrow fuselage. Beam-type fuselages have proven themselves and are used, including layout options called:

1. Sheathing - the design excludes longitudinally located segments, reinforcement occurs due to frames;
2. Spar - the element has significant dimensions, and the direct load falls on it;
3. Stringer ones - have an original shape, the area and cross-section are smaller than in the spar version.

Important! The uniform distribution of the load on all parts of the aircraft is carried out due to the internal frame of the fuselage, which is represented by the connection of various power elements along the entire length of the structure.

Wing design

The wing is one of the main structural elements aircraft, providing the creation of lift for flight and maneuvering in air masses Oh. Wings are used to accommodate take-off and landing devices, a power unit, fuel and attachments. The operational and flight characteristics airplane.

The main parts of the wing are the following list of elements:

1. A hull formed from spars, stringers, ribs, plating;
2. Slats and flaps ensuring smooth takeoff and landing;
3. Interceptors and ailerons - through them the aircraft is controlled in the airspace;
4. Brake flaps designed to reduce the speed of movement during landing;
5. Pylons required for mounting power units.

The structural-force diagram of the wing (the presence and location of parts under load) must provide stable resistance to the forces of torsion, shear and bending of the product. This includes longitudinal and transverse elements, as well as external cladding.

1. TO cross members include ribs;
2. The longitudinal element is represented by spars, which can be in the form of a monolithic beam and represent a truss. They are located throughout the entire volume of the inner part of the wing. Participate in imparting rigidity to the structure when exposed to bending and lateral forces at all stages of flight;
3. Stringer is also classified as a longitudinal element. Its placement is along the wing along the entire span. Works as a compensator of axial stress for wing bending loads;
4. Ribs are an element of transverse placement. The structure consists of trusses and thin beams. Gives profile to the wing. Provides surface rigidity while distributing a uniform load during the creation of a flight air cushion, as well as attaching the power unit;
5. The skin shapes the wing, providing maximum aerodynamic lift. Together with other structural elements, it increases the rigidity of the wing and compensates for external loads.

The classification of aircraft wings is carried out depending on the design features and the degree of operation of the outer skin, including:

1. Spar type. They are characterized by a slight thickness of the skin, forming a closed contour with the surface of the side members.
2. Monoblock type. The main external load is distributed over the surface of the thick skin, secured by a massive set of stringers. The cladding can be monolithic or consist of several layers.

Important! The joining of wing parts and their subsequent fastening must ensure the transmission and distribution of bending and torque moments arising under various operating conditions.

Aircraft engines

Thanks to the constant improvement of aviation power units, the development of modern aircraft construction continues. The first flights could not be long and were carried out exclusively with one pilot precisely because there were no powerful engines capable of developing the necessary traction force. Over the entire past period, aviation used the following types of aircraft engines:

1. Steam. The principle of operation was to convert steam energy into forward motion, transmitted to the aircraft propeller. Due to the low coefficient useful action used for a short time on the first aircraft models;
2. Piston engines are standard engines with internal combustion of fuel and transmission of torque to propellers. The availability of manufacturing from modern materials allows their use to this day on certain aircraft models. The efficiency is no more than 55.0%, but high reliability and ease of maintenance make the engine attractive;

1. Reactive. The operating principle is based on converting the energy of intense combustion of aviation fuel into the thrust necessary for flight. Today, this type of engine is most in demand in aircraft construction;
2. Gas turbine. They work on the principle of boundary heating and compression of fuel combustion gas aimed at rotating a turbine unit. They are widely used in military aviation. Used in aircraft such as Su-27, MiG-29, F-22, F-35;
3. Turboprop. One of the options for gas turbine engines. But the energy obtained during operation is converted into drive energy for the aircraft propeller. A small part of it is used to form a thrust jet. Mainly used in civil aviation;
4. Turbofan. Characterized by high efficiency. The technology used for injection of additional air for complete combustion of fuel ensures maximum operating efficiency and high environmental safety. Such engines have found their application in the creation of large airliners.

Important! The list of engines developed by aircraft designers is not limited to the above list. At different times, attempts were made to create various variations of power units. In the last century, work was even carried out on the construction of nuclear engines for the benefit of aviation. Prototypes were tested in the USSR (TU-95, AN-22) and the USA (Convair NB-36H), but were withdrawn from testing due to the high environmental hazard in aviation accidents.

Controls and signaling

The complex of on-board equipment, command and actuator devices of the aircraft are called controls. Commands are given from the pilot cabin and are carried out by elements of the wing plane and tail feathers. Different types of aircraft use different types of control systems: manual, semi-automatic and fully automated.

The controls, regardless of the type of control system, are divided as follows:

1. Basic control, which includes actions responsible for adjusting flight conditions, restoring the longitudinal balance of the aircraft in predetermined parameters, these include:

• levers directly controlled by the pilot (wheel, elevator, horizon, command panels);
• communications for connecting control levers with elements of actuators;
• direct executing devices (ailerons, stabilizers, spoiler systems, flaps, slats).

1. Additional control used during takeoff or landing modes.

When using manual or semi-automatic control of an aircraft, the pilot can be considered an integral part of the system. Only he can collect and analyze information about the aircraft’s position, load indicators, compliance of the flight direction with planned data, and make decisions appropriate to the situation.

To obtain objective information about the flight situation and the state of the aircraft components, the pilot uses groups of instruments, let’s name the main ones:

1. Aerobatic and used for navigation purposes. Determine coordinates, horizontal and vertical position, speed, linear deviations. They control the angle of attack in relation to the oncoming air flow, the operation of gyroscopic devices and many equally significant flight parameters. On modern aircraft models they are combined into a single flight and navigation system;
2. To control the operation of the power unit. They provide the pilot with information about the temperature and pressure of oil and aviation fuel, the flow rate of the working mixture, the number of revolutions of the crankshafts, the vibration indicator (tachometers, sensors, thermometers, etc.);
3. To monitor the functioning additional equipment and aviation systems. They include a set of measuring instruments, the elements of which are located in almost all structural parts of the aircraft (pressure gauges, air consumption indicators, pressure drop in pressurized closed cabins, flap positions, stabilizing devices, etc.);
4. To assess the state of the surrounding atmosphere. The main measured parameters are outside air temperature, atmospheric pressure, humidity, and speed indicators of air mass movement. Special barometers and other adapted measuring instruments are used.

Important! The measuring instruments used to monitor the condition of the machine and the external environment are specially designed and adapted for difficult operating conditions.

Takeoff and landing systems 2280

Takeoff and landing are considered critical periods during aircraft operation. During this period, maximum loads occur on the entire structure. Guarantee acceptable acceleration for lifting into the sky and a soft touch to the surface runway Only reliably designed landing gear can do this. In flight, they serve as an additional element to stiffen the wings.

The design of the most common chassis models is represented by the following elements:

• folding strut, compensating lot loads;
• shock absorber (group), ensures smooth operation of the aircraft when moving along the runway, compensates for shocks during contact with the ground, can be installed in conjunction with stabilizer dampers;
• braces, which act as reinforcers of structural rigidity, can be called rods, are located diagonally with respect to the rack;
• traverses attached to the fuselage structure and landing gear wings;
• orientation mechanism - to control the direction of movement on the lane;
• locking systems that ensure the rack is secured in the required position;
• cylinders designed to extend and retract the landing gear.

How many wheels does an airplane have? The number of wheels is determined depending on the model, weight and purpose of the aircraft. The most common is the placement of two main racks with two wheels. Heavier models are three-post (located under the bow and wings), four-post - two main and two additional support ones.

Video

The described design of the aircraft gives only a general idea of ​​the main structural components and allows us to determine the degree of importance of each element during the operation of the aircraft. Further study requires in-depth engineering training, special knowledge of aerodynamics, strength of materials, hydraulics and electrical equipment. At aircraft manufacturing enterprises, these issues are dealt with by people who have been trained and special training. You can independently study all the stages of creating an aircraft, but to do this you should be patient and be ready to gain new knowledge.

The aircraft is usually divided into main parts or assemblies that are complete in a constructive or technological sense. These parts include the wing, fuselage, horizontal and vertical tail, landing gear, power plant, control system and equipment.

An airplane wing (Fig. 2.2) creates lift and provides lateral stability and controllability. Engines, landing gear, fuel tanks, and weapons are often attached to the wing. The internal volumes of the wing are used to accommodate fuel, anti-icing devices and other equipment. Aircraft wings are equipped with mechanization devices to improve takeoff and landing characteristics.

Rice. 2.2. General view and layout of the aircraft

The fuselage or body serves to accommodate the crew, passengers or cargo, engines, front landing gear legs and connects all parts of the aircraft into one.

The horizontal tail provides longitudinal stability, controllability and balancing. It consists of a fixed part - the stabilizer and a moving part - the elevator.

The vertical tail provides directional stability, controllability and balancing; consists of a fixed part - the keel and a movable part - the rudder.

The landing gear is a system of supports designed for takeoff, travel after landing, movement around the airfield and parking. The landing gear design has elastic elements that absorb the kinetic energy of the aircraft.

The power plant is designed to create thrust force and includes a set of engines with systems that ensure their operation, and propellers (for aircraft with theater and propulsion engines).

The control system includes control command posts, control wiring and controls (rudders). Designed to control the aircraft along a given trajectory.

Aircraft equipment is a set of devices that ensure the safety of aircraft flight in difficult weather conditions and at different altitudes. Includes electrical, hydraulic, radio, flight and navigation, high-altitude and other aircraft equipment.

Aircraft layout

The layout of an aircraft is the process of spatially linking parts of an aircraft, placing cargo, passengers, crew, fuel, and equipment. The overall layout of the aircraft includes aerodynamic, internal (or weight) and structural-power layout.

Aerodynamic layout consists of choosing the layout of the aircraft, the relative arrangement of parts and giving the aircraft aerodynamic shapes. Since the aerodynamic design is given, when performing laboratory work the student needs to complete the internal layout, i.e. accommodate crew, passengers, cargo, fuel and equipment.

The crew cabin is located in the forward part of the fuselage and is separated from the other compartments by a partition. Its dimensions depend on the composition of the crew. On military aircraft, depending on the purpose, there may be one or two crew members; on passenger and transport aircraft, depending on the weight and length of the airline, the crew includes from two to four people: the ship’s commander, co-pilot, flight engineer, and navigator.

Fig.2.3. Cockpit layout

1,2 – pilot seats; 3,4 – seats for additional crew members.

The most important element of the flight deck layout is the pilot accommodation. In this case, the pilot must be provided with good visibility: right-left 20-30º from the line of sight, up-down – 16-20º and the optimal distance to the instrument panel and command control posts.

A typical layout of the flight deck of a passenger aircraft is shown in Fig. 2.3.

The dimensions and layout of passenger cabins depend on the number of passengers and the class of passenger equipment.

Currently, three classes are used, differing from each other in comfort and service conditions.

In the first, highest class, the greatest distance between the rows of seats is provided, the specific volume of the cabin per passenger is up to 1.8 m 3, and the ability to relax in chairs in a reclining position.

The second, or tourist class, is characterized by denser passenger seating, a specific volume of 1.5 m 3, and a seat back recline of up to 36º.

The third, economy class has even more dense seating for passengers with a specific volume of 0.9-1.2 m 3 seat backrest deviation of up to 25º.

Passenger seats are made in the form of blocks of two or three seats. The seat sizes depend on the passenger cabin class. The main dimensions of the seats are shown in the table.

Main Dimensions passenger seats

passenger-	Distance between armrests	Armrest width	Seat cushion length	Seat height above floor	Back width	Back length from seat cushion	Angle of backrest deviation from vertical	Seat height	Seat block width		Distance between rows of seats
1st class 2nd (tourist) 3rd (economy)	470 70 470 300 430 720 55 1100 1200 1420 960 440 50 450 320 430 700 36 1100 1030 1520 840 410 40 430 320 430 700 25 1100 970 1430 750

Passenger cabins along the length of the fuselage are usually divided into several salons separated by partitions.

When arranging passenger cabins, it is necessary to avoid placing passengers in the plane of rotation of the propellers and in the area where the engines are located. These volumes in the fuselage are used to accommodate kitchens, wardrobes or luggage spaces.

On large aircraft, flight attendants are included in the crew to serve passengers: for 30-50 passengers - one flight attendant. Each flight attendant is provided with a folding seat in the service area behind the flight deck or next to the entrance doors.

Passenger luggage is located under the floor of passenger cabins or in special luggage compartments in the rear fuselage at the rate of 0.25 m 3 per passenger.

When flying in winter, it is necessary to provide wardrobes. The area for wardrobes is 0.035-0.05 m2 per passenger. It is recommended to place wardrobes near the entrance doors.

On long-haul flights, passengers are provided with free meals. To accommodate food and related equipment on the aircraft, a buffet kitchen with a volume of 0.1-0.2 m 3 per passenger is provided.

The number of toilet facilities depends on the number of passengers and the duration of the flight. For flight durations of 2 to 4 hours, one toilet per 40 passengers is recommended. The floor area of ​​the toilet facilities must be at least 1.5-1.6 m2. The toilet facilities should be located in the forward and rear parts of the fuselage, near the entrance doors.

Aircraft equipment is usually combined into blocks, complexes and placed in special technical compartments. The technical compartments themselves are located in places to which a certain piece of equipment gravitates.

One of the options is the following arrangement of equipment units.

In the forward part of the fuselage in front of the pressurized cabin there are radar units (radars), equipment and approach antennas.

The subfloor of the pressurized cabin houses hydraulic equipment and equipment for aircraft control systems.

The fuselage directly behind the cabin houses oxygen, radio, electrical and fire-fighting equipment;

in the center section - equipment servicing the fuel system, mechanization, and landing gear; in the rear part of the fuselage there is equipment for aircraft controls and radio units.

Many people wonder: how does an airplane work? Indeed, it is precisely thanks to the special design of this vehicle and the materials used, such large and heavy airliners are able to rise into the air. Main components:

• wings;
• fuselage;
• "plumage";
• take-off and landing device;
• power point;
• control systems.

Each of these components has a special structure and may contain different types of components depending on the specific aircraft model. Detailed description parts of the aircraft will allow you not only to find out how it works, but also to understand the principle by which it is possible to fly at high speed.

Airplane structure

The fuselage is a body that includes several components. He collects wings into a single system, tail unit, power plant, chassis and other elements. The housing accommodates passengers, if we consider the device passenger plane. This part also houses equipment, fuels, engines and chassis. Any payload, be it passengers, luggage or transported equipment/goods, is placed in this part. For example, in military aircraft, weapons and other military equipment are located in this part. The characteristic streamlined drop-shaped body shape helps minimize drag while the aircraft is moving.

Wings

When listing the main parts of an aircraft, one cannot fail to mention the wings. The wing of the aircraft consists of two consoles: right and left. The main function of this element is to create lift. As an additional aid for these purposes, many modern aircraft have a fuselage with a flat bottom surface.

The wings of the aircraft are also equipped with the necessary “organs” for control during flight, namely for making turns in one direction or another. To improve takeoff and landing performance, the wings are additionally equipped with takeoff and landing mechanisms. They regulate the movement of the aircraft during takeoff and run, and also control takeoff and landing speeds. In some models, the design of the aircraft wing allows fuel to be placed in it.

In addition to two consoles, the wings are also equipped with two ailerons. These are moving components that make it possible to control the aircraft relative to the longitudinal axis. These elements function synchronously. However, they deviate in different directions. If one leans up, then the other leans down. The lifting force on a console tilted upward decreases. Due to this, the fuselage rotates.

Vertical tail

Plumage

The aircraft structure also includes a “tail”. This is another significant design element that includes the fin and stabilizer. The stabilizer has two consoles, like the wings of an aircraft. The main function of this component is to stabilize the movement of the aircraft. Thanks to this element, the aircraft manages to maintain the required altitude during flight under various atmospheric influences.

Keel– a component of the “feather”, which is responsible for maintaining the desired direction during movement. To change direction or height, two special rudders are provided, with the help of which these two elements of the “tail” are controlled.

It is worth considering that parts of the aircraft may have different names. For example, the “tail” of an aircraft in some cases refers to the rear fuselage and empennage, and sometimes this concept is used to refer solely to the fin.

Chassis

This part of the aircraft is also called the landing gear. Thanks to this component, not only take-off, but also a soft landing is ensured. The chassis is a whole mechanism of various devices. It's not just wheels. The takeoff and landing mechanism is much more complex. Its component alone (the cleaning/exhaust system) is a complex installation.

Power point

It is through the operation of the engine that the airliner is set in motion. The power plant is usually located either on the fuselage or under the wing. To understand how an airplane works, you need to understand the design of its engine. Main details:

• turbine;
• fan;
• compressor;
• the combustion chamber;
• nozzle.

At the beginning of the turbine there is a fan. It provides two functions at once: it pumps air and cools all components of the engine. Behind this element there is a compressor. Under high pressure, it transfers the air flow into the combustion chamber. Here, air is mixed with fuel, and the resulting mixture is ignited. After this, the flow is directed into the main part of the turbine, and it begins to rotate. The aircraft turbine design ensures the rotation of the fan. This ensures a closed system. To operate the engine, you only need to constantly supply air and fuel.

Assembly of simple airplanes

Aircraft classification

All airliners are divided into two main groups depending on their purpose: military and civilian. The main difference between aircraft of the second type is the presence of a cabin, which is equipped specifically for transporting passengers. Passenger aircraft, in turn, are divided into long-haul short-haul (fly at distances of up to 2000 km), medium (up to 4000 km) and long-distance (up to 9000 km). For long distance flights, intercontinental airliners are used. Also, depending on the type and device, such aircraft vary in weight.

Design features

The design of an airliner may vary depending on the specific type and purpose. Aerodynamically designed airplanes can have different wing geometries. Most often, passenger flights use aircraft that are designed according to classic scheme. The above-described arrangement of the main parts applies specifically to such airliners. Models of this type have a shortened bow. This provides improved visibility of the front hemisphere. The main disadvantage of such aircraft is the relatively low efficiency, which is explained by the need to use tails large area and, accordingly, mass.

Another type of aircraft is called “duck” because of the specific shape and location of the wing. The main parts in these models are placed differently than in classic ones. The horizontal tail (installed at the top of the keel) is located in front of the wing. This helps increase lift. And also thanks to this arrangement it is possible to reduce the mass and area of ​​the tail. In this case, the vertical tail (altitude stabilizer) operates in an undisturbed flow, which significantly increases its efficiency. Airplanes of this type are easier to fly than models of the classic type. One of the disadvantages is the reduced visibility of the lower hemisphere due to the presence of tail in front of the wing.

In contact with

Although different aircraft may differ greatly in design, in most cases they consist of the same basic components (Figure 2-4). Typically, an aircraft structure includes a fuselage, wings, tail, landing gear and power plant.

Fuselage. The fuselage is the central part of the aircraft and is designed to accommodate the crew, passengers and cargo. It also provides structural cohesion to the wings and tail. In the past, aircraft were constructed using an open truss structure made of wood, steel, or aluminum tubing (Figure 2-5). The most popular types of fuselage structures for modern aircraft are monocoque (French for “single shell”) and semi-monocoque. These types of designs are discussed in more detail later in this chapter.

Wings. Wings are airfoils attached to both sides of the fuselage. They provide the lift that supports the aircraft during flight. There are many wing designs, varying in shape and size. The mechanics of how a wing creates lift is discussed in Chapter 4, “Flight Aerodynamics.”

Wings can be attached to the top, middle or bottom of the fuselage. Such designs are called “high-,” “mid-,” and “low-wing,” respectively. The number of wings can also vary. Airplanes with a single set of wings are called monoplanes, and those with two sets of wings are called biplanes (Fig. 2-6).

Many high-wing aircraft are equipped with external braces, or struts, that transfer the load to the fuselage during flight and landing. Because the braces are located approximately in the middle of the wing, this type of design is called a semi-cantilever wing. Some high-wing airplanes and most low-wing airplanes have cantilever, or cantilever, wings that can support the load without external struts.

The main structural parts of the wings are the spar, stiffeners and stringers (Fig. 2-7). They are reinforced with trusses, I-beams, tubing or other means (including sheathing). The configuration of the wing stiffeners determines the shape and thickness of the wing (its aerodynamic profile). On most modern aircraft, fuel tanks are either integral to the wing structure or are flexible containers built into the wing.

There are two types of control surfaces attached to the trailing edge of the wing: ailerons and flaps. The ailerons are located approximately from the middle of each wing to its tip and move in opposite directions, creating aerodynamic forces that cause the aircraft to roll. The flaps extend from the fuselage to approximately the middle of each wing. When flying in cruise mode, they usually coincide with the surface of the wing. During takeoff and landing, the flaps extend, increasing the lift of the wing (Figure 2-8).

Alternative types of wings. Some time ago, the US Federal Aviation Administration (FAA) expanded the range of aircraft it certified by adding the category of “ultra-light aircraft”. The design of these aircraft can use a variety of methods to control flight and generate lift. They are discussed in detail in Chapter 4, Aerodynamics of Flight, which describes the effect of controls on various types of lifting surfaces (both conventional wing configurations and those involving bending or weight transfer). Thus, the wing of an aircraft controlled by weight transfer has a strongly curved shape, and flight control is provided by changing the position of the pilot’s body (Fig. 2-9).

Tail unit. The tail unit includes the entire tail group and consists of both fixed surfaces (vertical and horizontal stabilizers) and movable surfaces (rudder, elevator and one or more trim tabs) (Fig. 2-10).

The rudder is attached to the rear of the vertical stabilizer. During flight, it is used to move the nose of the aircraft left or right, while the elevator, attached to the rear of the horizontal stabilizer, moves the nose of the aircraft up or down. Trims are small moving parts on the trailing edge of the control surface that reduce the control input on the control levers. Trim tabs can be mounted on the ailerons, rudder and/or elevator and are controlled from the cockpit.

The second type of tail does not require an elevator at all. Instead, it includes a single horizontal stabilizer that rotates on a central hinge. This design is called an “all-rotating stabilizer.” The stabilizer, like the elevator, is actuated by the control wheel. For example, when the hinge is retracted, the all-moving stabilizer rotates so that its rear edge rises up. All-moving stabilizers are equipped with an anti-compensator, which is installed along their trailing edge (Fig. 2-11).

The anti-compensator moves in the same direction as the trailing edge of the stabilizer and makes the stabilizer less sensitive. In addition, the anti-compensator acts as a trimmer, reducing control force and helping to keep the all-moving stabilizer in the desired position.

Chassis. The landing gear provides support for the aircraft during parking, taxiing, takeoff and landing. The most common type of landing gear is wheeled, but aircraft can also be equipped with floats for landing on water or skis for landing on snow (Fig. 2-12).

The landing gear consists of three wheels - two main and a third, located either at the front or at the rear of the aircraft. A chassis with a rear wheel is called a “conventional chassis”.

Airplanes with conventional landing gear are sometimes called "tailwheel airplanes." When the third wheel is located on the nose of the aircraft, it is called a “nose wheel”, and the entire structure is called a “three-wheel landing gear”. A steerable nose or tail wheel allows you to control the movement of the aircraft on the ground. Most aircraft - both nosewheel and tailwheel - are controlled using rudder pedals. Some aircraft can be controlled using brakes with separate actuators on the right and left main wheels.

Power point. The power plant includes an engine and a propeller. The main function of the engine is to rotate the propeller. It also generates electrical power, is a source of vacuum for some on-board instruments, and, in most single-engine aircraft, is a source of heat for the pilot and passengers (Figure 2-13).

The engine is covered by a fairing or engine nacelle (various types of casing). The purpose of a fairing or engine nacelle is to reduce the aircraft's drag and also to provide engine cooling by directing air flow around the engine and cylinders.

The propeller, installed in front of the engine, converts the engine's rotational torque into thrust - a forward-pulling force that allows the aircraft to move in the air. The propeller can also be installed at the rear of the aircraft (push type propeller). A propeller is a rotating airfoil that provides thrust by generating aerodynamic force. An area of ​​low pressure forms behind the surface of the screw, and a high pressure area in front of it. The pressure difference pushes air through the propeller and the plane moves forward.

The efficiency of a propeller is determined by two parameters:
- the installation angle of the propeller blade, measured between the chord of the blade and the plane of rotation of the propeller;
- propeller pitch, defined as the distance that the propeller travels forward in one revolution (as if screwing into a solid body).

These two values, taken together, allow us to evaluate the efficiency of the propeller. The propellers are usually matched to a specific combination of aircraft design and powerplant so that maximum engine efficiency can be achieved. They can pull or push the aircraft (depending on the engine location).

Subcomponents. The subcomponents of an aircraft are the airframe, electrical system, flight control system and braking system.

The airframe is the basic structure of an aircraft, designed to withstand all aerodynamic loads as well as the stresses associated with the weight of fuel, crew and cargo. The main function of an aircraft's electrical system is to generate, regulate and distribute electrical energy within the aircraft. The electrical system can be powered from a variety of sources, such as engine-driven alternators, auxiliary power supplies, or external sources. It is used to power navigation devices of vital units (such as the anti-icing system, etc.), as well as for passenger services (for example, for cabin lighting).

The flight control system combines devices and systems that control the position of the aircraft in the air and, as a result, the trajectory of its flight. Most conventional aircraft use thin-edged, hinged control surfaces called elevators (for pitch), ailerons (for roll), and rudders (for yaw). Surfaces are controlled from the cockpit of the aircraft, by the pilot or autopilot.

Aircraft typically have hydraulic braking systems with disc or drum brakes, similar to automobile brakes. A disc brake consists of several plates (pads) that exert pressure on a rotating disc located between them, rigidly connected to the wheel hub. As a result of increased friction between the disc and pads, the wheels gradually slow down until they come to a complete stop. Discs and pads are made of either steel (as in cars) or carbon material, which is lighter and can absorb more energy. Aircraft braking systems are used primarily during the landing phase, absorbing enormous amounts of energy, so their lifespan is measured in number of landings rather than kilometers.

LYA nogo various types aircraft can be seen now - *** in the air - from the small PO-2 to the huge turboprop passenger ship TU-114. But all airplanes have common features of their design, and in order to get an idea of ​​​​the design of the aircraft, it is enough to get acquainted with one of the types.

Aviation festivals usually involve Yak-18 and Yak-P aircraft. In Fig. 1 shows a flight of Yak-18 aircraft in flight, and Fig. 2 this aircraft is shown in a semi-assembled form for clarity. This is a double

;) From the Greek words “aer” - air and “dynamis” - strength.

Paya training machine. The Yak-11 aircraft shown on the cover of the book is a two-seat fighter trainer, developing a significantly higher speed than the Yak-18.

Soviet pilot athletes won several records on these aircraft.

The main parts of the aircraft are: wing with ailerons, fuselage, tail unit, power plant, landing gear and tail wheel, steering.

The wing is designed to support, to “carry” the car in the air. It consists of a central part (Fig. 3), firmly connected to the fuselage, and the so-called consoles. The wing frame is made of two duralumin

Nievyh) beams - spars, which are fastened with duralumin ribs - ribs. At the rear of the wing there are small wings hinged to it - ailerons. With their help, the pilot can straighten the plane's roll or, conversely, tilt the car.

The fuselage is the body of the aircraft. The wings and power plant are attached to it. It contains cabins

Crew and passengers, cargo, as well as fuel tanks. The fuselage frame is made of steel pipes.

The tail - horizontal and vertical - serves to change and maintain the balance of the aircraft in flight. Using the elevator, the pilot can change the longitudinal position of the aircraft (tilt the aircraft down and up), and the rudder plays approximately the same role as the rudder of a boat. The stabilizer and fin are fixed surfaces; they contribute to the stable balance of the aircraft in the air.

The power plant on the Yak-18 aircraft consists of an air-cooled piston engine and a two-blade propeller.

The landing gear and tail wheel make it possible to take off and land. The Yak-18 aircraft, like most modern aircraft, has a retractable landing gear in flight. The pilot lifts and releases the landing gear using a special mechanism.

The steering control is the “nerves” of the aircraft. On the Yak-18 aircraft, the steering allows you to control the machine from both cockpits - the instructor and the student (Fig. 4). In front of each pilot’s seat there is a steering handle 1, with its help the pilot operates the elevator and ailerons. There are 2 pedals under your feet; with their help, the pilot moves the rudder.

Let's see how the pilot operates the rudders (we will explain the operation of the rudders further).

The steering handle, using a bracket 3, is pivotally connected to a longitudinal rotating pipe 4 (located on the cabin floor). This allows the pilot to tilt the stick back and forth, right and left. When he tilts it back, as they say “takes the handle,” its lower end tilts forward and a cable 5 attached to it, through a rocker 6, pulls the upper end of the elevator lever 8. As a result, the rudder tilts upward and the plane raises its nose; when the pilot “gives the stick away from himself,” the opposite happens: the elevator deflects down and the plane lowers its nose.

When the pilot moves the stick to the right, the longitudinal pipe 4, to which the stick is attached, also rotates to the right; this movement is transmitted through rockers and rods 9, 10 and 11 to ailerons 12, with the right aileron rising and the left one falling, and the plane rolls to the right. If the pilot moves the stick to the left, the left aileron goes up and the right aileron goes down, and the plane rolls to the left.

The pedals 2 are connected by cables 7 to the rudder lever 13. When the pilot presses the right pedal, the rudder moves to the right and the plane begins to turn to the right. When you press the left pedal, the rudder moves to the left and the plane begins to turn left.

Why can a plane make turns) and shapes? What forces make a heavy car tumble easily in the air? How does a pilot control these forces in curved flight? Of course, these are all the same aerodynamic...

P Before landing, the pilot turns off the engine or reduces its speed to the lowest possible speed. The plane begins to smoothly descend along an inclined trajectory. This type of descent of the aircraft is called gliding. To make it easier to understand the behavior of the aircraft...