Aircraft classification
depending on the functions they perform

The purpose of an aircraft is determined mainly by the design of its individual fragments, the overall assembly, the equipment used on the aircraft, as well as flight, weight and geometric properties. The site notes that mostly there are two large groups of aircraft - military and civilian.

Military aircraft are involved in air strikes against various military targets, manpower and equipment, as well as enemy communications. Air strikes are carried out both in the rear of the opposing side and in the front-line zone. In addition, military aircraft serve to protect their manpower and facilities from air strikes, as well as to transport troops and equipment, cargo and troops. Sometimes military aircraft are used for reconnaissance and for communication “with our own”. Military aircraft, in turn, are divided according to their purpose into several types - bombers, fighters, fighter-bombers, reconnaissance aircraft, military transport and auxiliary aircraft.

Bombers carry out bombing strikes on the most important enemy targets, as well as on communication centers and places where the largest number of manpower and equipment is observed. Most of the action of the bomber takes place in the rear. Fighters are used to repel enemy air strikes. They are divided into escort fighters (protecting their bombers from airstrikes), front-line fighters (protecting their troops above the battlefield and close to the front line), and interceptor fighters (intercepting and destroying enemy bombers). Fighter-bombers are equipped with bombs, missiles and cannons. They participate in striking in the forward zone and near rear, destroying the enemy air army.

Military transport aircraft are used when it is necessary to transfer cargo, equipment and troops. Reconnaissance aircraft conduct reconnaissance in the rear of the opposite side, and auxiliary aircraft carry out communications, spotting, sanitary and other functions.

Unlike the military, civil aircraft They work in the field of transportation of goods, mail, passengers, and are also used in some sectors of the national economy. They can be divided into several types, also depending on their purpose. Passenger aircraft used to transport passengers, various luggage, and mail. They come in mainline and local lines. The site notes that the division depends on the number of passengers, distance air transport, as well as the size of the runways. Trunk lines are divided into short, medium and long-distance, and carry out transportation at a distance of one to eleven thousand kilometers. Local airline aircraft include heavy, medium and light, and can carry from fifty-five (maximum) to eight (minimum) people.

Civil aircraft are also cargo aircraft; they are used to transport cargo of various volumes and weights. Special aircraft are used in agricultural, ambulance and polar aviation. In addition, there are aircraft that take part in geological exploration, to ensure the safety of forests (from fires, for example), and even for aerial photography. There are special training aircraft for pilot training - they come in initial training and transitional types. There are only two seats in initial training aircraft; they are quite easy to learn and technically, and are used for pilots who are sitting at the controls for the first time. Transition aircraft serve to train already experienced pilots to fly production aircraft already in use on various airlines.

In addition to the purpose, there is also a definition of aircraft according to the scheme. The relative position, types, shapes, and number of individual parts of the aircraft are taken into account. For example, airplanes vary in the number of wings and their arrangement, in the type of fuselage, landing gear and engines, and in the location of the tail. There are also mixed designs, one of which is an amphibious boat. The location, type and number of engines greatly influences the design and is determined mainly by the purpose of the aircraft, which was discussed above.

· equipment passenger seats comfortable armchairs, removable tables, individual lighting, ventilation and alarm;

· good soundproofing of cabins;

· performing flights at altitudes where bumpiness is less possible;

· equipping passenger cabins with buffets, wardrobes, toilets and other household premises.

Special requirements apply to cargo aircraft. Such requirements include:

· greater carrying capacity, increased dimensions of cargo compartments;

· availability of means of securing (mooring) cargo;

· Availability of on-board means of mechanized loading and unloading.

Many of the listed requirements are in conflict with each other: improvement of some characteristics leads to deterioration of others. For example, increase maximum speed flight causes an increase in landing speed and a deterioration in its maneuverability; meeting the requirements of strength, rigidity and survivability conflicts with the requirement to ensure a minimum mass of the structure; an increase in flight range is achieved by reducing the mass of transported cargo, etc. The impossibility of simultaneously fulfilling conflicting requirements makes it impossible to create a universal airplane or helicopter. Each airplane or helicopter is designed to perform specific missions.

3.2. Classification of airplanes, helicopters and aircraft engines

3.2.1. Aircraft classification

The variety of aircraft types and their use in the national economy necessitated their classification according to various criteria.

Among the many characteristics by which an aircraft can be classified, the most important is its purpose. This feature determines the choice of flight performance characteristics, the size and layout of the aircraft, the composition of the equipment on it, etc.

Main purpose civil aircraft– transportation of passengers, mail and cargo, performance of various national economic tasks. In accordance with this, according to their intended purpose, aircraft are divided into: transport, special purpose and educational. In turn, transport aircraft are divided into passenger and cargo aircraft. Based on maximum take-off weight, aircraft are divided into classes, table. 3.1.

Table 3.1

Aircraft classes

		Aircraft type
	75 or more	Il-96, Il-86, Il-76T, Il-62, Tu-154, Tu-204
		An-12, Il-18, Il-114, Tu-134, Yak-42
		An-24, An-26, An-30, Il-14, Yak-40
		An-2, L-410, M-15

Training aircraft are used to prepare and train flight personnel in various educational institutions civil aviation.

Special purpose aircraft: agricultural, ambulance, for protecting forests from fires and pests, for aerial photography, etc.

By flight range, aircraft are divided into long-haul (over 6,000 km), medium-haul (from 2,500 to 6,000 km), short-haul (from 1,000 to 2,500 km) and local airlines (up to 1,000 km).

Cargo aircraft, unlike passenger aircraft, have large internal volumes in the fuselage, allowing for the placement of various cargoes, a more durable floor, and are equipped with means of mechanized loading and unloading operations.

The classification of aircraft is shown in Fig. 3.1. Of the variety of design features, the main ones are highlighted: the number and location of wings; fuselage type; type of engines, their number and location; chassis type; type and location of plumage.

Rice. 3.1. Aircraft classification

Let's consider the features of aircraft designs, determined by the number and location of wings.

Based on the number of wings, airplanes are divided into monoplanes, that is, airplanes with one wing, and biplanes, an airplane with two wings located one above the other. The advantage of biplanes is better maneuverability compared to a monoplane, due to the fact that with an equal wing area, the wingspan of a biplane is smaller. However, due to the high drag due to the presence of inter-wing struts and braces, the biplane's flight speed is low. Currently, the An-2 biplane aircraft is used in civil aviation.

Most modern aircraft are designed as a monoplane.

Based on the location of the wing relative to the fuselage, low-wing, mid-wing and high-wing aircraft are distinguished. Each of these schemes has its own advantages and disadvantages.

Low-wing- an aircraft with a lower wing relative to the fuselage. It is this scheme that has become most widespread for passenger aircraft, due to its following advantages:

· low height of the landing gear, which reduces their weight, simplifies cleaning and reduces the volume of compartments for landing gear;

· ease of maintenance of aircraft engines when placed on the wing;

· during an emergency landing on water, good buoyancy is ensured;

· in case of an emergency landing with the landing gear not extended, the landing occurs on the wing, which creates less danger for passengers and crew.

The disadvantage of this scheme is that in the area where the wing and fuselage meet, the smoothness of air cut-off is disrupted and additional resistance arises, called interference, and is caused by the mutual influence of the wing on the fuselage. In addition, in a low-wing aircraft it is difficult to protect the engines located on the wing and under the wing from dust and dirt from the airfield runway.

Mid-ground- an aircraft whose wing is located approximately in the middle of the fuselage height. The main advantage of this design is minimal aerodynamic drag.

The disadvantages of the scheme include the difficulty of placing passengers, cargo and equipment in the middle part of the fuselage due to the need to pass the longitudinal power elements of the wing here.

High wing- an aircraft in which the wing is attached to the upper part of the fuselage.

The main advantages of the high-wing aircraft:

· low interference between the wing and the fuselage;

· placement of engines high from the surface of the runway. This reduces the likelihood of them being damaged when taxiing on the ground;

· good review lower hemisphere;

· the possibility of maximizing the use of the internal volumes of the fuselage, equipping it with means of mechanization of loading and unloading large-sized cargo.

The disadvantages of the scheme include:

· difficulty retracting the landing gear into the wing;

· difficulty in servicing engines located on the wing;

· the need to strengthen the structure of the lower part of the fuselage.

· Based on the type of fuselage, aircraft are divided into single-fuselage, double-boom with a gondola and “flying wing”.

· Most modern aircraft have a single fuselage to which the wing and tail are attached.

· Depending on the type and location of the plumage, there are three main schemes:

· rear position of the tail;

· forward position of the tail (duck type aircraft);

· tailless “flying wing” aircraft.

Most modern civil aircraft are designed with a tail unit. This scheme has the following varieties:

· central location of the vertical keel and horizontal location of the stabilizer;

· spaced vertical tail;

· V - shaped tail without a vertical keel.

Based on the type of landing gear, aircraft are divided into landplanes and seaplanes. The landing gear of land aircraft, as a rule, is wheeled, sometimes ski-mounted, while seaplanes have a boat or float-type landing gear.

Airplanes are also distinguished by the type, number and location of engines. Modern aircraft use piston (PD), turboprop (TVP) and turbojet (TRJ) engines.

The location of engines on an aircraft depends on their type, number, dimensions and purpose of the aircraft.

For multi-engine aircraft, engines with propellers are installed in nacelles in front of the wing.

Turbojet engines are most often located on pylons under the wing or in the rear fuselage.

The advantages of the first method: direct placement of engines in the air flow, unloading of the wing from bending and torques, ease of engine maintenance. However, the location of the engines close to the ground is associated with the risk of foreign objects falling into them from the runway surface. Airplanes with such an arrangement of engines also create difficulties in piloting with one failed engine (flight with asymmetrical thrust).

With the second method, the main advantages are the following:

· a wing free of superstructures has better aerodynamic characteristics (there is more space for placing wing mechanization devices);

· there are no difficulties when flying with asymmetrical thrust;

· noise level in aircraft cabins is reduced;

· the wing protects the engines from dirt when the aircraft moves on the ground;

· provides convenient engine maintenance.

However, this engine layout also has serious disadvantages:

· the horizontal tail must be moved upward and the keel must be strengthened;

· the fuselage in the area where the engines are located needs to be strengthened;

· the center of the aircraft moves backward as fuel burns out, reducing the stability of the aircraft.

3.2.2. Helicopter classification

Helicopters are classified according to various criteria, for example, by the maximum take-off weight (Table 3.2), by the type of rotor drive, the number and location of rotors, or the method of compensating the reaction torque of these rotors.

Table 3.2

Helicopter classes

	Maximum take-off weight, t	Helicopter type
	10 or more	Mi-6, Mi-10K, Mi-26
		Mi-4, Mi-8, Ka-32
		Ka-15, Ka-18

In most modern helicopters, the main rotor is driven through a transmission from the engines. When rotating, the main rotor experiences the action of the reactive torque MReact, which is the reaction of the air and is equal to Mkr - the torque on the main rotor shaft. This moment tends to rotate the helicopter fuselage in the direction opposite to the rotation of the propeller. The method of balancing the reactive torque of the rotor mainly determines the design of the helicopter.

The single-rotor helicopter design is currently the most common. Helicopters of this design have a tail rotor, which is carried on a long tail boom beyond the plane of rotation of the main rotor. The thrust created by the tail rotor helps balance the reaction torque of the main rotor. By changing the amount of tail rotor thrust, it is possible to carry out directional control, that is, rotate the helicopter relative to the vertical axis.

Single-rotor helicopters are simpler to manufacture and operate than others and therefore allow for a relatively lower cost per flight hour. Such helicopters are compact, have few parts protruding into the flow and allow them to achieve higher flight speeds than with other schemes. Sometimes a wing can be installed on such helicopters to increase speed. When approaching at horizontal speed, a lift force is created on the wing, as a result of which the main rotor is partially unloaded.

The power consumption (8...10%) of the engine to drive the tail rotor, as well as the presence of a long tail boom and a large-diameter main rotor, which increase the dimensions of the helicopter, are the disadvantages of this scheme.

For twin-rotor helicopters, balancing the reaction torque is achieved by imparting counter-rotation to the rotors. Twin-rotor helicopters can have different rotor arrangements.

In a coaxial design, the shaft of the upper rotor passes through the hollow shaft of the lower one. The planes of rotation of the propellers are removed from each other at such a distance as to prevent a collision between the blades of the upper and lower propellers in all flight modes.

The directional control of a coaxial helicopter is ensured by installing the blades of the upper and lower rotors at different angles of attack. The resulting difference in torque on the main rotors causes the helicopter to turn in the required direction. Sometimes, to improve directional control, such helicopters are equipped with rudders, the action of which is similar to the action of similar rudders on an airplane. Longitudinal and transverse control is carried out by simultaneous tilting of the planes of rotation of both rotors.

Helicopters with coaxial propellers are the most compact and maneuverable, and have a high weight transfer. However, the complexity of the design increases the cost of their production and causes difficulties during operation, especially in adjusting the supporting system.

With a longitudinal design, the rotors are installed at the ends of the fuselage. The propellers rotating in opposite directions are synchronized so that the blades of one propeller always pass between the blades of the other when rotating.

The advantage of helicopters of this design is their long, capacious fuselage, inside of which large cargo can be transported. Otherwise, they are inferior to single-rotor helicopters.

Transverse helicopters have two rotors located in the same plane on the sides of the fuselage and rotating in opposite directions. From an aerodynamic point of view, this layout of the rotors is the most appropriate, but the wings, which absorb loads from the rotors, significantly make the helicopter structure heavier.

3.2.3. Aircraft engine classification

The power plant is designed to create traction. It includes engines, propellers, engine nacelles, fuel and oil systems, engine and propeller control systems, etc.

Depending on the design design and the nature of the working process, engines are classified into piston engines (PD) and gas turbine engines (GTE). In turn, gas turbine engines are divided into: turbojet (TRD), turboprop (TVD), bypass turbojet (DTRD) and turbofan, Fig. 3.2.

Rice. 3.2. Classification of aircraft engines

Turbojet engines are lightweight, compact and reliable, and therefore occupy a dominant position on long-haul aircraft.

Compared to turbojet engines, turbojet engines have higher fuel efficiency, but their design is significantly heavier and complicated by a propeller, which also causes additional noise and vibration. The theater is installed on the wing and in the forward part of the fuselage. The presence of a propeller on the theater of operations limits other options for their location on the aircraft.

The turbojet engine is installed on the wing, under the wing on pylons, inside the fuselage, along its sides in the tail section. Each layout has its own advantages and disadvantages and is selected taking into account the type and number of engines, aerodynamic, strength, weight and other characteristics of the aircraft, and their operating conditions.

Piston engines run on B-70 and B-95/130 aviation gasoline. The thermal energy of the fuel burned in the cylinders is converted into mechanical energy and transferred propeller, which creates the thrust necessary for flight. Gas turbine engines run on aviation kerosene of the T-1, TS-1, RT-1, etc. brands.

Questions for self-control

1. What is “flight safety” and how is it ensured?

2. How is “operational efficiency” achieved?

3. In what areas is “passenger comfort” ensured?

4. By what characteristics and criteria are aircraft classified? Disadvantages and advantages of various aircraft designs.

5. Classification of helicopters. What are the advantages and disadvantages of various helicopter designs?

6. Give a classification of aircraft engines.

CHAPTER 4

AERODYNAMIC CHARACTERISTICS

AIRCRAFT

Aerohydromechanics (fluid and gas mechanics) is a science that studies the laws of motion and equilibrium of liquids and gases and their force interaction with streamlined bodies and boundary surfaces. Fluid mechanics is called hydromechanics, mechanics of a gaseous body – aeromechanics.

The development of aeronautics, aviation and rocket science aroused particular interest in the study of the force interaction of air and other gaseous media with bodies moving in them (aircraft wing, fuselage, propeller, airship, rockets, etc.).

The design and calculation of aircraft (helicopters) are based on the results obtained from aerodynamic studies. Taking into account aerodynamics, it is possible to select a rational external shape of the aircraft (taking into account the mutual influence of its parts) and establish permissible deviations in the external shape, dimensions, etc. during production.

For the aerodynamic calculation of an aircraft, i.e., to determine the possible range of speeds, altitude and flight range, as well as to determine such characteristics as stability and controllability of the aircraft, it is necessary to know the forces and moments acting on the aircraft in flight. To calculate the strength, reliability and durability of an aircraft, it is necessary to know the magnitude and distribution of aerodynamic forces over the surface of the aircraft. The answer to these questions is given by aerodynamics.

It is very important to determine the aerodynamic characteristics of the aircraft and its parts when flying with supersonic speeds, since in this case an additional problem arises of determining the temperature on the surface of the streamlined body and the heat exchange between the body and the environment.

Aerodynamics plays a big role not only in the design and calculation of an aircraft (helicopter), but also in its flight tests. With the help of aerodynamics data and flight tests, the permissible values ​​of deformations and speeds for the aircraft are established, as well as flight modes in which vibrations, shaking of the aircraft, etc. occur.

According to the principle of mechanical interaction of several moving bodies, the forces acting on the bodies depend on their relative motion. The essence of relative motion is as follows: if in a stationary air environment a body (for example, an airplane in the air) moves rectilinearly and uniformly with a speed V∞, then by simultaneously imparting the reverse velocity V∞ to the environment and the airplane, the so-called “reversed” motion is obtained, i.e. That is, an air flow flows onto a stationary body (for example, an air flow in a wind tunnel onto a stationary model aircraft), and the speed of the undisturbed flow is equal to V∞. In both cases, the equations describing the relative motion of the aircraft and air will be invariant. Thus, aerodynamic forces depend only on the relative motion of the body and air.

To determine the aerodynamic characteristics of bodies (for example, wings, fuselage and other parts of the aircraft) streamlined by air flow, a synthesis of theoretical and experimental methods is currently used: theoretical calculations with the introduction of experimental corrections or experimental studies taking into account theoretical corrections (on the influence variations of similarity criteria, boundary conditions, etc.). In both cases, digital computers are widely used for calculations and experimental data processing. After the creation of the aircraft, the final stage is flight testing - an experiment in natural conditions. Directly measuring aerodynamic forces (as, for example, in wind tunnels) during flight tests is difficult. Aerodynamic characteristics are determined by processing the parameters of the movement of the aircraft relative to the air measured during testing. To obtain a sufficient amount of experimental data, flights are carried out in various modes.

Aerodynamics is divided into two sections: low-speed aerodynamics and high-speed aerodynamics. The fundamental difference between these sections is as follows. When gas flow velocities are small compared to the speed of sound, in aerodynamic calculations the gas is considered to be practically incompressible and changes in the density and temperature of the gas inside the flow are not taken into account. At speeds comparable to the speed of sound, the phenomenon of gas compressibility cannot be neglected.

The task of aerodynamics is to determine the aerodynamic forces on which the flight characteristics of aircraft depend.

Aerodynamics as a science develops in two directions: experimental and theoretical. Theoretical aerodynamics finds solutions by analyzing the basic laws of hydroaerodynamics. However, due to the complexity of the processes occurring when air flows around bodies, the solutions are approximate and require experimental verification. Experimental aerodynamic studies are carried out in wind tunnels or directly during flight tests of aircraft. Flight tests provide the most reliable results. They are carried out, as a rule, after tests have been carried out in wind tunnels.

Wind tunnels are devices in which an air flow is artificially created to blow over the bodies being studied.

In Fig. Figure 4.1 shows a diagram of a wind tunnel. Fan – 2 is driven by electric motor – 1, which allows you to change the fan speed and air flow speed. The air sucked in by the fan, passing through the return channel - 4, enters through the tapering nozzle - 7 into the working part - 6, where the tested model is placed - 5. To lose air energy and prevent the appearance of vortices when the flow turns, guide vanes - 9, are used. and to create a uniform flow in the working area - straightening grille - 8. Expanding diffuser - 3 reduces the speed and accordingly increases the pressure of the air flow, which reduces the energy required to rotate the fan.

Rice. 4.1. Wind tunnel diagram: 1 – electric motor; 2 – fan; 3 – diffuser; 4 – return channel; 5 – tested model; 6 – working part of the wind tunnel; 7 – nozzle; 8 – straightening grid; 9 – guide vanes

To determine the aerodynamic forces acting on the test model, aerodynamic balances are used. The pressure on various parts of the surface of the model is measured through special holes connected to pressure gauges.

4.2. Characteristics of the air environment

Atmosphere called the gaseous shell surrounding the globe and rotating with it. The upper part of the atmosphere consists of ionized particles captured by the Earth's magnetic field. The atmosphere smoothly passes into outer space and its exact height is difficult to establish. Conventionally, the altitude of the atmosphere is assumed to be 2500 km: at this altitude, the air density is close to the density of outer space. The study of the state of the atmosphere is of great interest for aviation, since the flight performance characteristics of aircraft depend on the properties of the atmosphere. Meteorological conditions have a particularly great influence on the flight quality of aircraft.

As altitude increases, air pressure and density decrease. Atmospheric air parameters depend on the coordinates of the place and change over time within certain limits. Solar radiation has a significant impact on the state of the atmosphere. The atmosphere is in continuous interaction with space and earth.

The atmosphere consists of several layers: the troposphere, stratosphere, chemosphere, ionosphere, mesosphere and exosphere, each of which is characterized by varying temperature changes depending on altitude.

In the troposphere, the temperature decreases with altitude by an average of 6.5°C every 1000 m. In the stratosphere, the temperature remains almost constant. In the chemosphere, a warm layer of air lies between two cold layers, so there are two temperature gradients there: at the bottom on average +4°C per 1000 m, and at the top - 4.5°C per 1000 m. In the ionosphere, the temperature increases with height by an average of 10°C every 1000 m. In the mesosphere, the temperature decreases by an average of 3°C every 1000 m.

All layers are separated from each other by zones 1...2 km thick, called pauses: tropopause, stratopause, chemopause, ionopause, mesopause.

The lower layers of the atmosphere, in particular the troposphere and stratosphere, are currently of greatest interest to aviation.

Long-term observations of the state of the atmosphere in various places globe showed that the values ​​of temperature, pressure and air density vary depending on time and coordinates within very wide limits, which does not allow accurately predicting the state of the atmosphere at the time of flight. For example, in Siberia, the air temperature in winter at ocean level sometimes reaches 2130 K, and in summer 3030 K, i.e. during the year it changes by 900K. In mid-latitudes the temperature varies by about 700K. Significant fluctuations are also observed in temperature changes at different altitudes.

The range of pressure fluctuations is significant: in the middle latitudes at ocean level it varies from 1.04 to 0.93 bar (1 bar = 105 N/m2). The air density also changes accordingly (within ±10%).

The lack of certainty in the state of the atmosphere near the Earth and in the change in its state with increasing altitude creates serious difficulties in aerodynamic calculations of the flight characteristics of aircraft, which, as already noted, significantly depend on the state of the atmosphere. The need to unify calculations related to aircraft when solving practical problems, for example, uniform calibration of various flight instruments (speed meters, speed meters, etc.), recalculation of flight characteristics of aircraft obtained in specific atmospheric conditions, on others led to the creation of conventional characteristics of the atmosphere - standards. Such characteristics were introduced in the form of a conditional standard atmosphere (SA), which has the form of a table of numerical values physical parameters atmosphere for a number of altitudes.

4.3. General information about the laws of aerodynamics

Aerodynamics provides a qualitative explanation of the nature of the occurrence of aerodynamic forces and, with the help of special equations, allows us to obtain their quantitative assessment.

When studying the movement of gases, we proceed from the assumption that these media are complex with a continuous distribution of matter in space. The flow of gas (hereinafter referred to as air) in aerodynamics is usually represented in the form of separate elementary streams - closed contours in the form of tubes, through the side surface of which air cannot flow, Fig. 4.2. If at any point in space the speed, pressure and other characteristic quantities are constant in time, then such motion is called steady.

Let us apply the two most general laws of nature to the flow of air in a stream: the law of conservation of mass and the law of conservation of energy.

For the case of steady motion, the law of conservation of mass comes down to the fact that the same mass of air flows through each cross section of the stream per unit time, that is:

ρ1f1V1= ρ2f2V2=const,

where: ρ – mass density of air in the corresponding sections of the stream;

f is the cross-sectional area of ​​the stream;

V – air speed.

This equation is called the jet continuity equation.

The product ρfV represents the second mass flow rate of air passing through each cross section of the jet.

For low flow velocities (M< 0,3), когда сжимаемостью воздуха мож-но пренебречь, то есть когда ρ1 = ρ2 = const, уравнение неразрывности прини-мает вид:

f1V1= f2V2=const.

From this equation it is clear that when M< 0,3 скорость течения в струйке обратно пропорциональна площади ее поперечного сечения.

As the speed increases, it begins to influence the change in density more and more noticeably. For example, at speeds corresponding to M > 1, an increase in speed is possible only with an increase in the cross-sectional area of ​​the stream.

https://pandia.ru/text/78/049/images/image012_75.gif" width="29" height="38 src=">, and the potential energy, equal to the work of gravity relative to some conventional level, is mgh1. In addition, the air located above the first section produces work, advancing the mass of air located in front. This work is defined as the product of the pressure force P1f1 by the path V1Δτ. Thus, the air energy transferred during the time Δτ through section I-I will be:

Thus, based on the Bernoulli equation, we can conclude that in steady motion the sum static pressure and dynamic pressure is a constant value.

The aviation industry is developing every year. Today, civilian and military pilots use aircraft models of all configurations and varieties. Aircraft amaze with their variety and variations in purpose. Let's briefly study the types of aircraft and their names in order to classify this type of equipment for ourselves.

The world knows several separate criteria by which aviation experts classify various aircraft. One of the important aspects of systematization of technology is the function of the aircraft.. Today they are used by military and civilian vessels. Moreover, each category is divided into special groups.

In addition, it is also known division according to the speed characteristics of the airliner. Here aviators list groups of subsonic, transonic, supersonic and hypersonic models. This section of the classification is based on determining the acceleration of the liner relative to the speed of sound. Aircraft technology, which today is used for scientific and military purposes, although previously similar models worked for passenger transportation.

If we talk about the control method, we can distinguish two main types - manned aircraft and drones. The second group was used by the military and scientists. Such machines are widely used for space exploration.

Considering the types and purposes of aircraft, aviators will name and classification according to the design features of the device. Here we list the differences in the aerodynamic model, the number and type of wing, the shape of the tail, and the structure of the fuselage. The last subgroup also includes varieties that relate to the types and mounting of the chassis.

Finally, they consider and differences in type, number and installation method of engines. They include muscle, steam, air-jet, rocket, nuclear, and electric motors. In addition, ships are equipped with internal combustion engines (piston modifications of power plants) or combine several variations. Of course, in one review it is difficult to consider in detail the complete classification of aircraft, so we will focus on brief description main categories.

Functionality of the equipment

As stated above, airliners are divided into two main groups: aircraft for civil and military aviation. In addition, experimental devices are a separate type here. Each category here involves division into variations according to the type of purpose and functionality of the aircraft. Let's start by studying aircraft that are used for “peaceful” purposes.

Civil aircraft

Let's define in more detail what types of aircraft there are, the names and subtypes of flying modifications. Here aviators are talking about four model options. Let's list the categories like this:

• passenger liners;
• cargo sides;
• training airbuses;
• special purpose aircraft.

Note that modifications for passenger transportation are separately divided into groups that determine the flight range. Here they refer to mainline ships and airliners for local transport.

Aircraft classification

• short-range ones that cover distances of up to 2,000 km;
• medium, capable of flying 4,000 km;
• long-distance, operating flights up to 11,000 km.

In addition, the maximum capacity determines the following criteria for local airliners:

• heavy aircraft with 100 or more seats;
• medium modifications that carry up to 50 people;
• light airliners carrying a maximum of 20 passengers.

Among the examples local airlines Let's list the modifications SAAB , E.R.J. , Dash-8 , ATR . It is interesting that certain types of airliners of the local category are equipped with power plants of different classes. Here you can find models with jet engines and aircraft with turboprop engines.

Considering long-haul aircraft, let's name ships familiar to passengers Boeing And Airbus . Boeing aircraft are designed by an American corporation, and Airbus aircraft are designed by a European holding company. Both companies compete with each other, constantly developing and modernizing aircraft. Thus, today the Airbus A380 is considered the heaviest aircraft, although until the release of such a modification, American developments and 747 800 .

The 747 models were the first wide-body aircraft that are still in operation today. In addition, such aircraft are used by the best carriers in Russia and the world.

However, the Europeans are not lagging behind their main competitor. Modifications have gained popularity and recognition among pilots , Airbus A300 And A350 XWB. Model A300- the world's first wide-body aircraft equipped with two engines. As you can see, the possible variations in the classification of airliners cannot be described in one review. But knowing what types of airplanes there are and who created them, the reader will decide on personal preferences and find out the basics of aviation.

Military aviation

Now let's briefly study the typology of courts used by law enforcement agencies. Among these aircraft there are manned airliners and drones, modifications with different types of engines, including rocket engine subtypes. However, we will consider the division of these types according to profile criteria.

Military transport aircraft Il-76

Here, as in the civil classification, there is transport liners carrying out transportation personnel. This IL-76,An-12, 26 And 124 . In the USA, these functions are carried by models Boeing C-17, 97 And Douglas YC-15. In addition, the military also uses auxiliary equipment– medical aircraft, communications aircraft, spotters. However, military aircraft developments also use several categories of vehicles that are found only here. Their list is as follows:

As you can see, the category of military aircraft is quite extensive and deserves serious study. We have only briefly described the main criteria for systematizing such a group. However, aviation experts prefer to classify aircraft using a comprehensive study that includes Full description side designs. Let's dwell on this issue.

About design features

Belonging to a specific category of an airliner is determined by five characteristics. Here the designers talk about the number and method of attaching the wings, the type of fuselage, the location of the tail and the type of landing gear. In addition, the quantity, location of fixation and types of motor are important. Let's find out the known variations in the design of the sides.

Differences in design features are an important criterion when classifying airliners

If we consider the classification of the wing, then the airliners are divided into polyplanes, biplanes and monoplanes. Moreover, in the last category there are three more subtypes: low-plane, mid-plane and high-plane sides. This criterion determines the relative position and fixation of the fuselage and wings. As for the typology of the fuselage, aviators distinguish single-fuselage and double-boom modifications. Here you can also find the following varieties: gondola, boat, load-bearing fuselage and combinations of these types.

Aerodynamic performance is an important classification criterion because it affects. Here the designers call the types of normal design, “duck”, “tailless” and “flying wing”. In addition, the “tandem”, “longitudinal triplane” and convertible design are known.

Airliner landing gear is systematized according to the design and method of fixing the supports. These elements are divided into roller, float, tracked, combined types and air-supported landing gear. The engines are installed on the wing or in the fuselage. Moreover, the airliners are equipped with one engine or a large number of engines. In addition, the type of power plant also plays a decisive role in systematizing the class of aircraft.

Unmanned aerial vehicles have found application in the scientific and military spheres

Modern aviation has several types of aircraft, which are classified according to various criteria.
According to their intended purpose, aircraft are divided into civil, military and experimental aircraft.
Aircraft classification
Airbus A380 - a giant in the world passenger airliners
Boeing aircraft are the main competitor in the field of passenger transportation of the European holding company, which produces Airbuses.

To carry out military air transport, various transport aircraft and helicopters of military and civil aviation are used.

From a transportation point of view, transport aircraft and helicopters can be classified by purpose, payload capacity and type of installed engines.

According to their purpose, transport aircraft (helicopters) are divided into passenger, cargo and cargo-passenger.

Passenger aircraft are intended primarily for the transportation of passengers, baggage and mail, for which they have appropriate household equipment that provides convenience and comfort to passengers. Cargo can be transported in small quantities in trunks located under the floor of the passenger cabin.

Civil aviation passenger aircraft, depending on passenger capacity, flight range and class of airfields used, are divided into mainline and local airlines.

Long-haul aircraft, in turn, are divided into long-haul (LMC), medium-haul (CMC) and short-haul (VMS).

The DMS includes: Il-62, Tu-114 and the first supersonic passenger aircraft Tu-144.

To CMC -Tu-154, Tu-104, An-10, Il-18.

For the Navy - Tu-134, Tu-124.

Local airlines include: An-24, Yak-40, Be-30, An-2.

Cargo aircraft are designed to transport cargo and equipment; they have special equipment that ensures cargo loading and securing, as well as the necessary climatic conditions inside the cargo cabin during flight. If necessary, they can be equipped with removable seats for transporting people.

Cargo aircraft include: An-24t, An-12, An-22 and Mi-4A, Mi-8, Mi-6, Mi-10 helicopters.

Utility aircraft are designed to transport passengers and cargo. In cargo-passenger aircraft there are separate rooms for passengers (usually the upper floor) and cargo (usually the lower floor) or the passenger cabin equipment is easily removable, which allows, if necessary, to quickly adapt the aircraft (helicopter) to a combined or purely freight transportation. Aircraft adapted for rapid conversion from a passenger to a cargo version are called convertible aircraft.

According to their carrying capacity, transport aircraft and helicopters are divided into light ones, with a normal landing load of up to 11 tons, medium ones, up to 20 tons, and heavy ones, more than 20 tons.

Light aircraft and helicopters are used relatively little in the work of military communications - only to carry out individual small shipments or in conditions when there are no airfields in the unloading area suitable for landing medium-duty aircraft.

For military transportation Currently, the most widely used are medium-sized aircraft: cargo type An-12 and passenger types Il-18, Tu-104, An-10 and Tu-154. However, it is known that as aircraft payload and passenger capacity increase, worker productivity air transport increases, and the cost of transportation decreases, it becomes possible to carry out a given volume of transportation with a smaller number of aircraft, which helps reduce the frequency of aircraft movements in airport areas and improves flight safety. Considering the development of military air transport, there is every reason to believe that heavy transport aircraft with a payload capacity of 100 tons and above and passenger or convertible aircraft with a capacity of 300-500 people or more will be increasingly used for their implementation.

Based on the type of installed engines, modern transport aircraft and helicopters are divided into those with gas turbine (GTE) and piston (PD) engines.

Aircraft with gas turbine engines, in turn, are divided into those with turbojet engines (TRE) and turboprop engines (TVD).

Airplanes with turboprop engines have much lower specific fuel consumption compared to jet engines.

Currently, transport aircraft with bypass turbojet engines (DTRE), which occupy an intermediate position in terms of efficiency between theater engines and turbojet engines, are becoming increasingly widespread.

With the further increase in the speeds of transport aircraft, the most promising are aircraft with compressorless air-breathing jet engines, ramjet engines (ramjet engines) and pulsating engines (pulsating engines), which at cruising flight speeds corresponding to Mach number > 3 have better performance characteristics compared to DTJEs.

From the point of view of departmental affiliation, transport aircraft (helicopters) are divided into military and civil aviation aircraft (helicopters).

Installed on military aircraft optional equipment related to the performance of combat missions (weapons, special equipment for parachute landing of troops, equipment and cargo, in-flight refueling system, etc.).

Today there are quite a few different aircraft, but not all of them are called airplanes. This term refers to any aircraft that is designed to fly in the sky due to a power plant that creates thrust and a wing that remains motionless at all times. It is the fixed wing that is the main characteristic of the aircraft, distinguishing it from any other aircraft.

This term itself appeared back in 1857 - then a Russian pilot called a balloon that way; there were no airplanes in the sense in which we use this word today. It was mentioned in a meaning close to its modern one a few years later - in 1863. It was an article “Aeronautics”, published in 1863 in the magazine “Voice”. The author was journalist Arkady Evald.

Today there are a huge number of aircraft classifications. For example, by the number of wings, by the aerodynamic system, by the type of chassis and by speed.

In this text we will look at one of the main typologies. Any aircraft, first of all, are divided by purpose. They are civilian, military and experimental. Each of these categories, in turn, is also divided into several types.

As is obvious from the name itself, these are aircraft designed to transport passengers or cargo. The first flight on an aircraft of this type took place in Russia more than a hundred years ago - in 1914. The flight was made from St. Petersburg to Kyiv, and the plane was called “Ilya Muromets”. There were 16 passengers on board.

Today, the most famous and frequently used airliner of our time is the American Douglas DC-3 model. He first flew with passengers back in 1935. Over the past time, the aircraft has been improved, and many other models, including those of Soviet aviation, were created on its basis.

Civil aircraft can be transport, training or special purpose. Transport vehicles, in turn, are divided into according to their purpose:

• Freight - for transporting goods;
• Passenger planes are the planes we fly;

Varieties of such Vehicle so many. The easiest way is to divide them simply by manufacturer. In fact, the vast majority of the world's aircraft are produced by such companies:

Boeing

This is an American company that appeared a long time ago, in 1916. Since then, it has been producing aircraft for civil aviation. The most popular model is the Boeing 737. It is this aircraft, produced in 1968, that is used most often today. The name “Boeing” itself has already become practically synonymous with the word airplane.

Airbus

This company today is the main competitor of the Boeing described above, although it was founded much later - in 1970. This European company, today its main office is located in France. Some models of this manufacturer are economical, which makes them a serious competitor to Boeing.

Military

Military aircraft are designed to conduct combat operations, that is, protection from the enemy or, conversely, attack. They are divided into several types, but in general, they can perform a variety of tasks, depending on the current situation.

Bombers

This subspecies of military aircraft essentially has one task - to destroy any ground objects from the air. This occurs by dropping bombs or missiles on the target. Today there are many different models, among the most commonly used are the Su-24 and Su-34.

It was the bomber that was converted into the first passenger aircraft, the Ilya Muromets, which was discussed above. During the First World War, the aircraft was re-equipped and subsequently it always served as a bomber.

Fighters

Unlike bombers, such aircraft are used for air combat. The name “fighter” sounds loud and menacing, but in fact such aircraft belong to defense equipment. They are almost never used for offensive purposes. Fighters were actively used by both sides during the Second World War - the most famous models are the MiG-3 and Yak-1.

It is interesting that in the very first models of fighters, it was not a machine gun, as it is today, but a revolver, so the rate of fire was much lower.

Fighter-bombers

Naturally, the two models described above were combined to obtain a universal model that combines the functions of both types. The main advantage of this variety is the ability to bomb any ground targets without any cover at all. Such aircraft are very light, maneuverable and equipped with powerful weapons. The most successful models are Mig-27, Su-17, SEPECAT Jaguar.

Interceptors

In fact, this is not a completely separate class, just a subtype of fighter. The main difference is that interceptors are designed to destroy a specific target, namely enemy bombers. They are also slightly different in structure - such models are additionally equipped with radar equipment. famous models - Su-15, Su-9 and others.

The purpose of attack aircraft is to support ground forces from the air. They were also often used simply to destroy various objects. The most popular model is called Il-2 and this aircraft is the most mass-produced in history - almost 37 thousand units were produced.