Features of choosing comfortable seats in the aircraft cabin. Airplane design elements What does an airplane for children consist of?

Airplane

Airplane

a heavier-than-air aircraft with a wing on which aerodynamic lift is generated when moving, and a power plant that creates thrust for flight in the atmosphere. The main parts of the aircraft: wing (one or two), empennage (all this together is called the airframe), avionics; military aircraft also have aviation weapons.

The wing is the main part of the aircraft. Airplanes with one wing are called monoplanes, with two – biplanes. The middle part of the wing, attached to the fuselage or integral with it, is called the center section; The side detachable parts of the wing - consoles - are attached to the center section. On the wing are located (ailerons, elevons, spoilers) and devices with which the wings are adjusted (flaps, slats, etc.). The wing houses fuel tanks, various components (for example, landing gear), communications, etc. Engines are installed on the wing or under it (on pylons). Up to mid. 20th century the planes had trapezoidal wings (in plan view). With the advent of jet engines, the shape of the wing changed and became swept. in combination with a gas turbine jet engine allows you to achieve flight speeds twice and three times higher. In the 1960-70s. airplanes were created with a wing that varied in flight: during takeoff and landing, as well as when flying at subsonic speeds, the characteristics of a straight (traditional) wing were better; in flight at supersonic speed it turns, acquiring a sweep shape, which significantly improves its aerodynamics (MiG-23, USSR; F-111, USA).

The fuselage is the body of the aircraft that carries the wings, tail and landing gear. It houses the crew cabin and passenger compartment, cargo compartments, and equipment. Sometimes the fuselage is replaced with tail booms or combined with the wing. Until the 1930s Most aircraft had open cockpits. With the increase in flight speed and altitude, the cabins began to be covered with a streamlined “canopy”. Flights at high altitudes required the creation of sealed cabins that provided them with the pressure and temperature necessary for normal human life. The streamlined cigar-shaped fuselage provides it with minimal resistance to air flow in flight. Supersonic aircraft have a fuselage with a very pointed nose. The cross-sectional shape of the fuselage of modern aircraft can be round, oval, in the form of the intersection of two circles, close to rectangular, etc. Created in the 1965-70s. so-called wide-body aircraft with a fuselage with a diameter of 5.5–6.5 m made it possible to significantly increase the carrying capacity of aircraft (IL-86, USSR; Boeing-747, USA). The fuselage structure consists of load-bearing elements (spars, stringers, frames) and skin. Power elements are made from lightweight and durable structural materials (aluminum and titanium alloys, composite materials). at the dawn of aviation it was made of linen, then from plywood and from cone. 1920 – metal (aluminum and its alloys). The vast majority of aircraft are made using a single-fuselage design, very rarely using a double-boom design, and only a few experimental aircraft are fuselageless, the so-called. (XB-35, USA).

The tail provides stability and controllability of the aircraft in longitudinal and lateral movement. For most aircraft, the empennage is located on the rear part of the fuselage and consists of a stabilizer and elevator (horizontal tail), fin and rudder (vertical tail). supersonic aircraft may not have elevators or rudder due to their low efficiency at high speeds. Their functions are performed by steerable (all-rotating) and stabilizer. The design of the tail is similar to that of the wing and in most cases follows its shape. The most common type is single-fin tail, but aircraft with spaced vertical tail are being created (Su-27, MiG-31). There are known cases of creating a V-shaped tail, combining the functions of a keel and stabilizer (Bonanza-35, USA). Many supersonic aircraft, especially military ones, do not have stabilizers (Mirage-2000, France; Vulcan, UK; Tu-144).

The landing gear is used to move the aircraft around the airfield during taxiing and along the runway during takeoff and landing. The most common wheeled chassis. In winter, skis can be installed on light aircraft. U seaplanes Instead of wheels, floats-boats are attached to the chassis. During flight, the wheeled landing gear is retracted into the wing or fuselage to reduce airflow. Sports, training and other light aircraft are often built with fixed landing gear, which are simpler and lighter than retractable ones. Modern jet aircraft have landing gear with a nose gear under the nose of the fuselage and two legs near the center of gravity of the aircraft under the fuselage or wing. This tricycle landing gear ensures safer and more stable aircraft movement at higher speeds during takeoff and landing. Heavy passenger aircraft are equipped with multi-support and multi-wheel landing gear to reduce loads and pressure on the aircraft. All landing gear is equipped with liquid-gas or liquid shock absorbers to soften the shocks that occur when the aircraft lands and moves along the airfield. For taxiing the aircraft, the front support has a rotating one. The movement of the aircraft on the ground is controlled by separate braking of the main landing gear wheels.

The power plant of the aircraft includes aircraft engines (from 1 to 4), propellers, air intakes, jet nozzles, fuel supply systems, lubrication, control, etc. Almost to the end. 1940s the main type of engine was piston engine internal combustion, driving rotation. From the end 1940s gas turbine engines began to be used on military and civil aviation aircraft jet engines– turbojet and turbofan. The engines are installed in the forward part of the fuselage (mainly on propeller-driven aircraft), built into the wing, suspended on pylons under the wing, installed above the wing (mainly in seaplanes), and placed on the rear part of the fuselage. On heavy passenger aircraft, preference is given to rear-mounted engines, since this reduces noise in the passenger cabin.

1 – ; 2 – cockpit; 3 – toilets; 4.18 – wardrobe; 5.14 – cargo; 6 – luggage; 7 – first passenger cabin with 66 seats; 8 – engine; 9 - ; 10 – vertical wing tip; 11 – external; 12 – inner flap; 13 – second passenger cabin with 234 seats; 15 – cargo on pallets in nets; 16 – emergency exit; 17 – loads in nets; 19 – keel; 20 – rudder; 21 – elevator; 22 – ; 23 – stabilizer; 24 – fuselage; 25 – ; 26 – main landing gear; 27 – ; 28 – fuel compartments; 29 – wings; 30 – buffet with elevator to the lower deck; 31 – cargo floor with spherical supports; 32 – entrance door; 33 – nose landing gear

The aircraft equipment ensures the aircraft, flight safety, and the creation of conditions necessary for the life of crew members and passengers. Aircraft navigation is provided by flight navigation, radio and radar equipment. To increase flight safety, fire-fighting equipment, emergency rescue and external equipment, anti-icing and other systems are designed. Life support systems include air conditioning and cabin pressurization units, etc. The use of microprocessor technology in aircraft control systems has made it possible to reduce the number of crews of passenger and transport aircraft to 2–3 people. The aircraft is controlled in flight using elevators and rudder (on the trailing edges of the stabilizers and fin) and ailerons deflected in opposite directions. The pilots control the rudders and ailerons from the cockpit. During regular flights along the highway, control of the aircraft is transferred to the autopilot, which not only maintains the flight direction, but also controls the operation of the engines and maintains the specified flight mode.

Aircraft armament military aviation determined by their purpose and what tasks they solve in combat operations. The military is armed with surface-to-air cruise missiles and air-to-air missiles, aircraft cannons and machine guns, aircraft bombs, aircraft sea mines and torpedoes.

Encyclopedia "Technology". - M.: Rosman. 2006 .

Airplane

(obsolete -) - heavier than air for flights in the atmosphere with the help of a power plant that creates thrust and a fixed wing, on which aerodynamic lift is generated when moving in the air. The immobility of the wing, which distinguishes the wing from rotary-wing aircraft that have a “rotating wing” (main rotor), and from an aircraft with flapping wings (flyers), is to some extent conditional, since in a number of designs the wing can change in flight installation angle, etc. The concept of S., which originated in the late 18th - early 19th centuries. (J. Cayley) and which assumed the flight of an aircraft using a propulsion unit (propeller) and a lifting surface (wing) separated by function, during the development of aircraft technology it turned out to be the most successful in terms of the totality of flight characteristics and operational qualities, and it became most widespread among aircraft with different principles of creating lift and constructive methods of their implementation ( cm. also Aviation).
Aircraft classification.
Based on their purpose, a distinction is made between civilian and military vehicles. Civil vehicles include passenger, cargo, cargo-passenger, administrative, sports, agricultural, and other vehicles for the national economy. Passenger aircraft are divided into mainline aircraft and aircraft of local airlines. Military aircraft include fighters (air combat aircraft, fighter-bombers, fighter-interceptors, multi-role aircraft), attack aircraft, bombers (front-line, long-range, intercontinental), reconnaissance aircraft (tactical, operational, strategic), military transport aircraft (light, medium, heavy). , anti-submarine, combat support (radar patrol and guidance, jammers, air control posts, in-flight refueling, etc.). Military and civil aviation includes educational, training, ambulance, patrol, and search and rescue aircraft. S. According to the type of propulsion, S. is classified as screw or jet. According to the type of engine, a propeller is often called a piston, turboprop, or jet (in particular, rocket), and according to the number of engines, for example, two-, three-, or four-engine. Depending on the maximum flight speed, aircraft are divided into subsonic (flight M(() 1) and hypersonic (M(() > > 1; often taken M(() > > 4-5). Based on basing conditions, land aircraft are distinguished based, ship-based aircraft, seaplanes (flying boats or floats) and amphibious aircraft, and according to the requirements for the length of the runway - vertical, short and conventional take-off and landing aircraft. Various maneuvering abilities (maximum operational load value). distinguishes maneuverable, limited maneuverable, and non-maneuverable aircraft. According to the stage of development, aircraft are classified as experimental, experimental, and production aircraft, and in contrast to the original model, aircraft with a crew are called manned; for some types, aircraft without a crew are called unmanned. S. (fighters, attack aircraft, training aircraft) often indicate the number of crew members (single or double).
Many airfoil names are determined by their design and aerodynamic design. Based on the number of wings, monoplanes, biplanes (including sesquiplanes), triplanes and polyplanes are distinguished, and monoplanes, depending on the location of the wing relative to the fuselage, can be low-wing, mid-wing and high-wing. A monoplane without external wing reinforcements (struts) is called a cantilever, and with a wing mounted on struts above the fuselage it is called a monoplane. An aircraft with a wing sweep that can be changed in flight is often called an aircraft of variable geometry; depending on the location of the tail, there are aircraft of the normal design (with a tail), aircraft of the "" type (horizontal, no tail) and aircraft of the "" type (with horizontal tail located in front of the wing). According to the type of fuselage, the aircraft can be single-fuselage or double-boom, and the aircraft without a fuselage is called a “flying wing.” S. with a fuselage diameter of more than 5.5-6 m are called wide-body. Vertical take-off and landing aircraft have their own classification (with rotary propellers, rotary wings, lifting or lift-propulsion engines, etc.). Some classification concepts, such as “light”, “heavy”, “long-range”, etc., are arbitrary and do not always have strictly defined boundaries for aircraft of various types (fighters, bombers, transport aircraft). ) may correspond to significantly different numerical values ​​of take-off mass and flight range.
Aerodynamics of the aircraft.
The lifting force that supports the wing in the air is formed as a result of the asymmetric air flow around the wing, which occurs when the wing profile is asymmetrically shaped, oriented at a certain positive angle of attack to the flow, or under the influence of both of these factors. In these cases, the flow velocity on the upper surface of the wing is greater, and the pressure (in accordance with Bernoulli's equation) is lower than on the lower surface; As a result, a pressure difference is created under the wing and above the wing and a lifting force arises. Theoretical approaches to determining the lift force of a wing profile (for an ideal incompressible fluid) are reflected in the well-known Zhukovsky theorem. The total aerodynamic force RA (called the aerodynamic force of a glider) acting on the sky when an air flow flows around it can be represented in the speed coordinate system as two components - the aerodynamic lift force Ya and the drag force Xa (in the general case, the presence of a lateral force is also possible Za). The force Ya is determined mainly by the lifting forces of the wing and horizon, and the tail, and the force Xa, which is oppositely directed in relation to the flight speed, owes its origin to the friction of air on the surface of the aircraft (friction resistance), the pressure difference acting on the frontal and rear parts of the aircraft elements ( pressure resistance, cm. Profile drag, Bottom drag), and the flow bevel behind the wing associated with the formation of lift (inductive drag); in addition, at high flight speeds (near- and supersonic), , caused by the formation of shock waves ( cm. Aerodynamic drag). The aerodynamic force of a glider S. and its components are proportional to the velocity pressure
q = V2/2
((() - air density, V - flight speed) and some characteristic area, which is usually taken as S:
Ya = cyaqS,
Xa = cxaqS,
Moreover, the proportionality coefficient (lift coefficient cya and drag coefficient cxa) depend mainly on the geometric shapes of the aircraft’s parts, its orientation in the flow (angle of attack), Reynolds number, and at high speeds also on the M(()) number. Aerodynamic perfection Aircraft is characterized by the ratio of the lift force to the total drag force, called aerodynamic quality:
K = Ya/Xa = cya/cxa
In steady (V = const) horizontal flight, the weight of the aircraft G is balanced by the lift force (Ya = G), and the thrust P of the power plant must compensate for the drag (P = Xa). From the resulting relation G = KP it follows, for example, that the implementation of a higher value of K in the aircraft design would make it possible, at a fixed value of G, to reduce the required thrust for the same flight speed and, therefore, and in some other cases (for example, at the same value P) increase the load capacity or by S. In the early period (before the early 20s), S. had rough aerodynamic shapes and their aerodynamic quality values ​​were in the range K = 4-7. In the 1930s, which had straight wings and a flight speed of 300-350 km/h, values ​​of K = 13-15 were obtained. This was achieved mainly through the use of a cantilever monoplane design, improved wing profiles, streamlined fuselages, closed cockpits, rigid smooth skin (instead of fabric or corrugated metal), retracting the landing gear, cowling engines, etc. With the subsequent creation of higher-speed S. the possibilities for improving aerodynamic efficiency have become more limited. Nevertheless, on passenger S. 80s. with high subsonic flight speeds and swept wings, the maximum values ​​of aerodynamic quality were K = 15-18. On supersonic aircraft, to reduce wave drag, wings with a thin profile, high sweep, or other planform shapes with low aspect ratio are used. However, aircraft with such wings have less subsonic flight speeds than aircraft with subsonic flight speeds.
Aircraft design.
It must provide high aerodynamic characteristics, have the necessary strength, rigidity, survivability, endurance (fatigue resistance), be technologically advanced in production and maintenance, and have a minimum weight (this is one of the main criteria for aircraft perfection). In general, the aircraft consists of the following main parts: wing, fuselage, empennage, landing gear (all of this together is called the airframe), power plant, and on-board equipment; military S. have also.
Wing is the main load-bearing surface of the structure and also ensures its lateral stability. On the wing there are means of its mechanization (flaps, slats, etc.), controls (ailerons, elevons, spoilers), and in some wing configurations, landing gear supports are also fixed and engines are installed. consists of a frame with a longitudinal (spars, stringers) and transverse (ribs) strength set and sheathing. The internal volume of the wing is used to accommodate fuel, various units, communications, etc. The most important moments in the development of aircraft related to the design of the wing were completed in the 30s. the transition from the biplane design to the cantilever monoplane and which began in the late 40s and early 50s. transition from a straight wing to a swept wing. On heavy aircraft with a long flight range, for which it is important to increase the aerodynamic quality, the monoplane design made it possible to increase for this purpose, and for more power-equipped aircraft (fighters), to use a decrease in wing area and drag to increase flight speed. The creation of cantilever monoplanes was made possible thanks to advances in structural mechanics and wing profiling, as well as the use of high-strength materials. The use of a swept wing made it possible to realize the potential for further increasing flight speed when using gas turbine engines. When a certain flight speed (critical number M(())) is reached, local supersonic zones with shock waves are formed on the wing, which leads to the appearance of wave drag. For a swept wing, due to the sliding principle, the occurrence of such unfavorable phenomena is pushed to the region of higher flight speeds (critical number M(() is greater than that of a straight wing); and in supersonic flow, the intensity of the resulting shock waves () of a subsonic S. wing is usually 20-35 (°), and for a supersonic S. it reaches 40-60 (°). .
In the 50-80s. created large number Aircraft of various types with turboprop engines and turbojet engines, differing in speed and flight profile, maneuverability and other properties. Accordingly, wings have been used on them, varying in plan form, aspect ratio, relative thickness, structural-power design, etc. Along with the swept wing, the delta wing has become widespread, combining the properties of high sweep, favorable for high supersonic flight speeds ( () 55-70°), low elongation and small relative profile thickness. In connection with the need to ensure high aerodynamic characteristics for certain types of airplanes in a wide range of flight speeds, aircraft were created with a wing that varied in flight (()) 15-70°), which realized the advantages of a straight wing with a relatively large aspect ratio (takeoff and landing modes and at subsonic speeds) and highly swept wings (flight at supersonic speeds). A variation of this scheme is all-rotary. In maneuverable aircraft, a wing with variable sweep along the leading edge has been used, which includes a trapezoidal part with moderate sweep and root flares of a highly swept wing, which improve the load-bearing properties of the wing at high angles of attack. The wing design with a forward-swept wing (FSW) has not become widespread due to the aeroelastic instability (divergence) of the wing at elevated flight speeds. The advent of composite materials opened up the possibility of eliminating this drawback by providing the necessary rigidity of the wing without noticeably weighing the structure, and the COS, which has favorable aerodynamic characteristics at high angles of attack, became available in the late 70s and 80s. the object of extensive theoretical and experimental research. S. of different speed ranges differ in wing elongation
(() = 12/S (l - wing span).
To increase aerodynamic quality, increase (), to reduce wave drag - decrease. If the aspect ratio of subsonic swept wings is usually (-) = 7-8 for passenger and transport aircraft and () = 4-4.5 for fighters, then for supersonic fighters () = 2-3.5. To ensure the necessary lateral stability, the wing consoles are installed (when viewed from the front) at a certain angle to the horizontal plane (the so-called transverse V of the wing). The improvement in the aerodynamic characteristics of the wing is largely due to the improvement of its profile. At various stages of aircraft development, the choice of wing profile was determined by aerodynamic or design requirements and the level of scientific knowledge. A flat wing was found in early aircraft designs, but all the first aircraft to fly already had profiled wings. To obtain greater lifting force, thin curved wings were first used (S. of the early period), and later - wings with a thick profile (cantilever monoplanes of the 20s). As flight speeds increased, less curved and thinner profiles were used. At the end of the 30s. Work was carried out on the so-called laminar profiles of low resistance, but they were not widely used, since ensuring laminar flow placed high demands on the quality of finish and cleanliness of the wing surface. In the 70s For subsonic aircraft, supercritical profiles have been developed that make it possible to increase the value of the critical number M(()). On aircraft with high supersonic flight speeds, to reduce wave drag, wings with a small relative profile thickness ((c) = 2-6%) and a sharp leading edge are used. edge. The geometric parameters of the wing are variable along its span: it has a narrowing, the values ​​of c decrease towards the ends of the wing, aerodynamic and geometric are used, etc.
An important characteristic of S. is equal to
G/S = cyyV2/2.
At all stages of aircraft development, it increased - on high-speed aircraft due to a decrease in wing area in order to reduce drag and increase flight speed, and on heavy aircraft due to an accelerated increase in the mass of the aircraft. With an increase in the specific load on the wing, the take-off speed increases accordingly and landing, the required length of the runway increases, and it also becomes more difficult to pilot the aircraft during landing. The reduction in take-off speed and landing speed is ensured by the mechanization of the wing, which allows, when deflecting the flaps and flaps, to increase the maximum values ​​of the coefficient cy, and for some structures, also the area of ​​the load-bearing surface. Wing mechanization devices began to be developed in the 20s, and became widespread in the 30s. At first, simple flaps were used, later retractable and slotted flaps (including two- and three-slotted ones) appeared. Some types of wing mechanization (slats, etc.) are also used in flight, during maneuvering. The idea of ​​matching the shape of the wing profile with the flight mode is the basis of the adaptive wing. In the 50s. To increase the lift of the wing at low flight speeds, it began to be used, in particular, to blow off the boundary layer by blowing air bleed from the engine onto the upper surfaces of the wing tips and flaps. In the 70s Short take-off and landing aircraft (STOL) began to be created with the so-called energy mechanization of the wing, based on the use of engine energy to increase lift by blowing the wing or flaps with the jet stream of the engines.
Fuselage serves to combine into one whole the various parts of the aircraft (wings, empennage, etc.), to accommodate the crew cabin, units and systems of on-board equipment, and also, depending on the type and design of the aircraft, passenger compartments and cargo compartments, engines , weapons and landing gear compartments, fuel tanks, etc. In the early stages of aircraft development, its wing was connected to the tail using an open truss or a box-shaped truss fuselage covered with fabric or rigid skin. Truss fuselages were replaced by so-called beam fuselages with various combinations of strength sets - longitudinal (spars, stringers) and transverse (frames) and “working” skin. This design made it possible to give the fuselage various well-streamlined shapes. For a long time, an open or protected by a front visor cockpit prevailed, and on heavy aircraft they were fitted into the contours of the fuselage. As flight speed increased, the cabins of light aircraft began to be covered with a streamlined canopy. Flights at high altitudes required the creation of sealed cabins (on combat and passenger airplanes) with the provision of air parameters in them necessary for normal human life. On modern aircraft, various forms of cross-section of the fuselage have become widespread - round, oval, in the form of the intersection of two circles, etc. On a fuselage with a cross-section close to rectangular and with a specially profiled bottom, it is possible to obtain some additional lifting force (load-bearing fuselage). . The area of ​​the fuselage section of a light aircraft is determined by the dimensions of the crew cabin or the dimensions of the engines (when installed in the fuselage), and on heavy aircraft - by the dimensions of the passenger or cargo cabin, weapons compartments, etc. The creation in the second half of the 60s. Wide-body aircraft with a diameter of about 6 m made it possible to significantly increase payload and passenger capacity. The length of the fuselage is determined not only by the conditions for placing the transported load, fuel, and equipment, but also by the requirements related to the stability and controllability of the aircraft (ensuring the required position of the center of gravity and the distance from it to the tail). To reduce wave drag, the fuselages of supersonic aircraft have a large aspect ratio, a pointed nose, and sometimes in the area of ​​interface with the wing the fuselage is “tucked in” (when viewed from above) in accordance with the so-called area rule. Most aircraft are made according to a single-fuselage design. Double-boom aircraft were built relatively rarely, and even less frequently were fuselage aircraft.
Plumage provides longitudinal and directional stability, balancing and controllability of the aircraft. Most of the aircraft created, especially subsonic ones, had a normal design, that is, with a tail unit, usually consisting of fixed and deflectable (control) surfaces: the stabilizer and elevator form (GO), and keel and rudder - (VO). According to the structural-power scheme, the tail is similar to the wing, and at high speed, the VO and GO, like the wing, are swept-shaped. On heavy subsonic airplanes, to facilitate balancing, the stabilizer is sometimes made adjustable, that is, with a variable installation angle in flight. At supersonic flight speeds, the effectiveness of the rudders decreases; therefore, on supersonic aircraft, the stabilizer and fin can be controlled, including all-moving ones (forward and horizontal without rudders). The most common type is single-fin tail, but aircraft with spaced-out wings are also created. The design of a V-shaped tail unit that performs the functions of GO and VO is known. A fairly large number of engines, especially supersonic ones, are made according to the “tailless” design (there is no GO). A small number of aircraft have been built according to the canard design (with a front cylinder), but it continues to attract attention, in particular, due to the advantage of using the positive lift force created by the front cylinder to balance the car.
Chassis serves to move the aircraft around the airfield (during taxiing, takeoff, and landing), as well as to soften the shocks that occur during landing and movement of the aircraft. The most common type is a wheeled chassis, but on light aircraft in winter conditions a ski chassis is sometimes used. Attempts were made to create a tracked chassis, which turned out to be too heavy. The necessary seaworthiness and stability on the water of seaplanes are provided by floats or a fuselage boat. Chassis resistance can reach 40% of the frontal drag, so in the early 40s. To increase flight speed, retractable landing gear began to be widely used. Depending on the design of the fuselage, the landing gear is retracted into the wing, fuselage, and engine nacelles. Low-speed aircraft are sometimes built with fixed landing gear, which is lighter and simpler in design. To ensure a stable position of the vehicle on the ground, its chassis includes at least three supports. Previously, a tricycle landing gear with a low tail support was mainly used, but jet aircraft are equipped with a landing gear with a front landing gear, which ensures a safer landing at high speeds and stable movement of the aircraft during the takeoff and run. In addition, the horizontal position of the fuselage (with the front support) helps to reduce the impact of the engine jet stream on the airfield surface. On a number of aircraft, it is used with two main supports along the fuselage and auxiliary supports at the ends of the wing. One of the advantages of this design is the absence of nacelles on the wing for retracting the landing gear, which worsen the aerodynamic characteristics of the wing. On the M-4 heavy bomber, the front strut of the bicycle landing gear was “heavy” during takeoff, which increased the speed and shortened the takeoff run. The landing gear support usually includes a strut, liquid-gas or liquid, struts, retraction mechanisms and wheels. The wheels of the main supports, and sometimes the front supports, are equipped with brakes, which are used to reduce the length of the run after landing, as well as to hold the aircraft in place when the engines are running (before the takeoff roll, when testing the engines, etc.). To ensure steering, the front support has an orienting wheel. Control of the vehicle's movement on the ground at low speeds is ensured by separate braking of the wheels of the main supports, as well as by the creation of asymmetrical engine thrust. When this method is ineffective or impossible (bicycle chassis, single-engine layout in combination with a small chassis track, etc.), the front support is controlled. Heavy passenger and transport aircraft are equipped with multi-legged and multi-wheeled chassis to reduce the loads and pressures on the airfield pavement. The search for new, in particular non-contact, takeoff and landing devices (for example, hovercraft landing gear) is aimed at expanding the capabilities of landing aircraft.
Aircraft power plant.
Creates the necessary thrust over the entire range of operating conditions and turns on the engines ( cm. Aviation engine), propellers, air intakes, jet nozzles, fuel supply systems, lubrication, control and regulation, etc. Almost until the end of the 40s. The main type of engine for S. was an air- or liquid-cooled piston engine. Important stages in the development of power plants with piston engines are the creation of variable pitch propellers (effective in a wide range of flight conditions); increase in liter power due to an increase in the compression ratio, which became possible after a significant increase in the anti-knock properties of aviation gasoline; providing the required engine power at altitude by supercharging them using special superchargers. To reduce the aerodynamic drag of the power plant, the aim was to close the star-shaped air-cooled piston engines with annular profiling hoods, as well as to remove the radiators of the liquid-cooled piston engines into the wing or fuselage tunnels. The power of the aircraft piston engine was increased to 3160 kW, and the flight speed of aircraft with a piston engine was increased to 700-750 km/h. However, further growth in speed was hampered by a sharp increase in the aerodynamic drag of the aircraft and a decrease in the efficiency of the propeller due to the increasing influence of air compressibility and the associated increase in the required engine power, while the possibilities of reducing its weight and size had already been exhausted. This circumstance stimulated the development and introduction of lighter and more powerful gas turbine engines (turbojet engines and turboprop engines).
Turbojet engines have become widespread in combat aircraft, and turboprop engines and turbojet engines have become widespread in passenger and transport aircraft. Rocket engines (liquid rocket engines) are not widely used due to the short available flight duration (it is necessary to have not only an oxidizer on board, but also an oxidizer), although they were used in a number of experimental rockets, in which record flight speeds were achieved. Traction, economic and aviation gas turbine engines were continuously improved by increasing the parameters of the engine's operating process, using new materials, design solutions and technological processes. An increase in flight speeds up to high supersonic ones (M(() = 3) was achieved using turbojet engines equipped with an afterburner, which made it possible to significantly (by 50% or more) increase the engine thrust. In experimental aircraft, power plants consisting only of ramjet engines (starting from a ramjet engine), as well as combined installations (+ ramjet engine) Power plants with a ramjet engine provide further expansion of the speed range of the ramjet engine (). cm. Hypersonic aircraft). In subsonic passenger and transport aircraft, economical turbojet engines were used, first with a low bypass ratio, and later (in the 60-70s) with a high bypass ratio. The specific fuel consumption on a supersonic aircraft reaches 0.2 kg/(Nph) in afterburner flight modes; for subsonic aircraft in cruising flight modes it is increased to 0.22-0.3 kg/(kW h) for turboprop engines and 0. 07-0.058 kg/(N h) for turbojet bypass engines. The creation of highly loaded propellers that maintain high efficiency up to high flight speeds (M(() 0.8) forms the basis for the development of turbofan engines, which are 15-20% more economical than turbojet bypass engines. Passenger aircraft engines are equipped with thrust reversal devices on landing to reduce the run length and are low-noise ( cm. Noise standards). The number of engines in a power plant depends mainly on the purpose of the engine, its main parameters, and the requirements for flight characteristics. The total power (thrust) of the power plant, determined by the required starting power-to-weight ratio (thrust-to-weight ratio) of the aircraft, is selected based on the conditions of not exceeding the specified take-off run length, ensuring a climb in the event of one engine failure, achieving maximum flight speed at a given altitude, etc. Thrust-to-weight ratio of a modern supersonic fighter reaches 1.2, while for a subsonic passenger aircraft the S. is usually in the range of 0.22-0.35. There are various options for placing engines on the S. Piston engines were usually installed on the wing and in the forward part of the fuselage. The engines on turboprop aircraft are installed similarly. On jet aircraft, the layout solutions are more varied. On light combat aircraft, one or two turbojet engines are usually installed in the fuselage. On heavy jet aircraft, the practice was to place the engines in the root part of the wing, but the scheme of suspending the engines on pylons under the wing became more widespread. On a passenger aircraft, engines (2, 3, or 4) are often placed on the rear part of the fuselage, and in the three-engine version, one engine is placed inside the fuselage, and it is placed in the root part of the fin. The advantages of such arrangements include reduced noise in the passenger cabin and increased aerodynamic quality due to a “clean” wing. Three-engine versions of passenger aircraft are also made according to a scheme with two engines on pylons under the wing and one in the rear fuselage. On some supersonic aircraft, the engine nacelles are located directly on the lower surface of the wing, and special profiling of the outer contours of the nacelles makes it possible to use a system of shock waves (increasing pressure) to obtain additional lift on the wing. Installing engines on top of the wing is used in short take-off and landing aircraft with airflow over the upper surface of the wing.
Aviation engines use liquid - gasoline in piston engines and the so-called (like kerosene) in gas turbine engines ( cm. Aviation fuel). Due to the depletion of natural oil reserves, synthetic fuels, cryogenic fuels (in 1988 the USSR created an experimental aircraft Tu-155, using liquefied gas as fuel), as well as aviation nuclear power plants, can be used. A number of lightweight experimental solar cells have been created that use the energy of solar panels ( cm. Solar plane), of which the most famous is “Solar” (USA); It carried the flight from Paris to London in 1981. Construction of demonstration aircraft with a muscular propeller drive continues ( cm. Muscle plane). In 1988, the flight range of a muscle plane reached about 120 km at a speed of over 30 km/h.
Aircraft equipment.
Ensures piloting, flight safety, and creation of the necessary conditions for the life of members. crew and passengers and performing tasks related to the purpose of the aircraft. Flight navigation, radio engineering and radar equipment are used for aircraft navigation. To increase flight safety, fire-fighting, emergency rescue, external lighting equipment, anti-icing and other systems are designed. The life support system includes air conditioning and cabin pressurization systems, oxygen equipment. The power supply for power supply systems and units is provided by electrical, hydraulic, and pneumatic systems. The target equipment is determined by type C. This includes, for example, units for spraying chemicals on agricultural vehicles, household equipment for passenger vehicles, surveillance and sighting systems for combat vehicles, reconnaissance, anti-submarine, airborne transport, search and rescue equipment, and radar patrol equipment. and guidance, electronic warfare, etc. (instruments, indicators, signaling devices) provides the crew with the information necessary to carry out the flight mission, control the operation of the power plant and on-board equipment. In the early stages of development, aircraft were equipped with a small number of instruments that controlled the basic flight parameters (altitude, heading, roll, speed) and engine speed, and could fly under conditions of visual visibility of the horizon and ground references. The expansion of the practical use of satellites and the increase in flight range and altitude required the creation of on-board equipment that would allow long-term flights, day and night, in difficult meteorological and geographic conditions. In the first half of the 30s. Gyroscopic means were created (artificial horizon, gyro-semi-compass), which provided for flights in clouds, fog, and at night, and autopilots began to be used, freeing the pilot from the tedious work of maintaining a given flight mode on long routes. At the end of the 20s. Aircraft transceiver radio stations began to be introduced. In the 30s On-board and ground-based radio equipment (radio compasses, direction finders, radio beacons, radio markers) began to be used to determine the flight direction and location of the aircraft, as well as in the first instrument approach systems. During World War II, radars were used in combat aircraft, which were used for target detection and navigation. In the post-war years, the functionality of aircraft equipment was significantly expanded, and its accuracy was increased. Flight navigation equipment is created based on the use of a variety of means: combined systems for determining airspeed parameters, Doppler meters of ground speed and drift angle, heading systems with magnetic, gyroscopic and astronomical sensors, radio engineering systems for short and long-range navigation, high-precision inertial systems, radar sights to clarify the location of the S. and determine the meteorological situation, etc. More accurate instrumental (instrument) approach systems, and then automatic landing systems, were used. On-board digital computers are used to process information and automatically control the operation of various systems. In combat aircraft, airborne radar stations are widely used in surveillance and targeting systems for detecting air and ground targets and targeting guided missiles at them. For the same purposes, optical-electronic systems are used, including heat direction finders, laser locators, etc. The information content of display means has increased. The use of on-screen indicators and head-up indicators is increasing. The latter allow the pilot to see the necessary information projected in front of him, without being distracted from the view of the extra-cockpit space in critical flight modes. Expert crew assistance systems based on artificial intelligence and a voice control system were tested experimentally (in the late 80s). On modern airplanes, the layout of the flight deck, the selection of the optimal composition, and the location of information display equipment, control panels, etc. are made taking into account the requirements of aviation ergonomics.
Armament.
The armament of military weapons is intended to destroy manpower, air, ground, and sea (underwater and surface) targets and includes (depending on the weapon’s purpose) machine gun and cannon, bomber, mine, torpedo, and missile weapons. In this case, small arms and missile weapons can be offensive or serve for defense against enemy fighters (for example, on bombers, military transport aircraft). The formation of the main combat aircraft (fighters and bombers) dates back to the period of the First World War. Initially, conventional (army) machine guns were used. It was important to use a synchronizer, which allows firing through the plane of rotation of the propeller. Fighters were armed with fixed synchronized machine guns, and on bombers machine guns were mounted on rotating devices to organize all-round defense. The ancestor of bomber aviation was the aircraft "" (1913). Its bomb load reached 500 kg. During the period between the two world wars, special machine-gun and cannon weapons were created that met the requirements of aviation use (low weight and dimensions, high, low recoil, remote control of firing and reloading, etc.). A new type of weapon was created in the 30s. uncontrollable. The Second World War clearly demonstrated the great role of weaponry as a means of armed struggle. In the first half of the 50s. S. appeared, armed with guided missiles. The basis of modern missile weapons are guided missiles of the air-to-air and air-to-surface classes with different firing ranges and various guidance methods. The launch range reaches 300 km for air-to-air missiles and tactical air-to-surface missiles ( cm. Aviation rocket).
In the early 80s. bombers began to be armed with strategic air-to-surface cruise missiles with a launch range of up to 2500 km. On light rockets, the rockets are suspended on external holders, while on heavy ones they can also be placed inside the fuselage (including on rotating drums).
Construction materials.
The main material for the manufacture of the frame of most of the first aircraft was wood; fabrics (for example, percale) were used as covering, and metal was used only to connect various components of the aircraft, in the chassis and in the engines. The first all-metal Ss were built in 1912-1915. In the early 20s. became widespread, which for many years became the main structural material in aircraft construction, due to the combination of high strength and low weight properties that are important for aircraft. Stronger steels were used in heavily loaded structural elements (for example, in the chassis). For a long time (until the Second World War), structures of mixed (wooden and metal) construction were also created. With increasing flight speed, the requirements for structural materials have increased due to the increased (due to aerodynamic heating) operating temperature of structural elements. It is close to the air stagnation temperature, which depends on the flight speed and is determined by the relation
T0 T(1 + 0.2M(()2),
where T is the air temperature. When flying in the lower stratosphere (T = 216.65 K), the numbers M(() = 1, M(() = 2 and M(() = 3) will correspond to the air flow stagnation temperature values ​​of 260, 390, 607 K (or - 13, 117, 334(-)С). Aluminum alloys predominate in the design of aircraft with maximum flight speeds corresponding to numbers M(() = 2-2.2). At higher speeds, special steels are also beginning to be used. Mastering hypersonic flight speeds requires the use of heat-resistant alloys, “hot”, heat-protected or cooled structures (for example, with the help of liquid hydrogen fuel, which has a large cooling resource). Since the 70s, they have been used in auxiliary structures with high specific strength and rigidity. These power elements will significantly increase the weight perfection of the aircraft's design. In the 80s, a number of lightweight aircraft were created, almost entirely made of composite materials, including the record-breaking aircraft, which in 1986 made a non-stop flight around the world without refueling. in flight.
Airplane control.
Many schemes and configurations of the aircraft were tested before it became stable and well-controllable in flight. The aircraft's stability and controllability in a wide range of operating conditions is ensured by an appropriate choice of geometric parameters of the wing, tail, controls and its alignment, as well as control automation. To maintain a given flight mode and change the aircraft's trajectory, control parts (rudders) are used, which in the traditional case include an elevator, a rudder, and oppositely deflected ones ( cm. also governing bodies). Control is carried out by changing aerodynamic forces and moments when these surfaces deflect. To deflect the control surfaces, it moves the control handle (or steering wheel) and pedals installed in the cockpit. Using the control stick, the elevator (longitudinal control) and ailerons (lateral control) are deflected, and the rudder (directional control) is deflected using the pedals. connected to the steering wheels by flexible (cable) or rigid control wiring. On many types of aircraft, control levers are equipped at the workstations of two crew members. To reduce the forces on the control levers necessary to deflect the rudders, various types of compensation for the hinge moment occurring on them are used. In steady-state flight conditions, it may be necessary to deflect the rudders to balance C. In this case, auxiliary control surfaces - trimmers - are used to compensate for the hinge moment. At large hinge moments (on heavy or supersonic aircraft), hydraulic steering actuators are used to deflect the rudders. In the 70s The so-called (EDSU) has found application. On the S. with EMDS, there is no mechanical control wiring (or is backup), and the transmission of signals from the command levers to the rudder deflection actuators is carried out via electrical communications. EMDS has a smaller mass and allows increasing reliability by redundant communication lines. Fly-by-wire systems are also used in new types of control systems based on the use of sensitive sensors, computer technology and high-speed drives. These include systems that make it possible to control a statically unstable aircraft (such aerodynamic configurations provide benefits in aerodynamic and weight characteristics), as well as systems designed to reduce the loads acting on the aircraft during maneuvering or flight in a turbulent atmosphere, to suppress flutter and etc. ( cm. Active control systems). New control systems open up the possibility of implementing unusual forms of aircraft movement in the vertical and horizontal planes due to the direct control of lifting and lateral forces (without transient processes associated with a preliminary change in the angular position of the aircraft during traditional control), which increases control speed and piloting accuracy. In the 80s experimental remote control systems using fiber-optic communication channels have been created.
Aircraft operation.
To prepare aircraft for flight and take off and land, specially equipped airfields are needed. Depending on the take-off weight, type of landing gear, and takeoff and landing characteristics, the aircraft can be operated from airfields with natural or artificial surfaces and with different runway lengths. Unpaved airfields are used primarily for local air lines, agricultural airfields, forward-based combat airfields (fighters, attack aircraft, etc.), as well as military transport and cargo airfields with all-terrain chassis (with low specific gravity). load on the ground) and powerful wing mechanization. Some types of aircraft (heavy bombers, long-haul passenger aircraft, etc.) require concrete airfields, and the required runway length can reach 3000-4500 m. Preparing aircraft for flight includes checking the serviceability of systems and equipment, refueling, aircraft loading, suspension of bomber and missile weapons, etc. Passenger aircraft flights are controlled by ground air traffic control services and are carried out along specially established air routes with the necessary separation. Many types of aircraft are capable of autonomous flight. The crew of the aircraft is varied in terms of the number of members and the functions of its members and is determined by the type S. In addition to one or two pilots, it may include a navigator, flight engineer, flight radio operator, gunners and on-board equipment operators, flight attendants (on passenger aircraft). The largest number of crew members are S. , equipped with special radio-electronic equipment (up to 10-12 people on anti-submarine navigation systems, up to 14-17 people on long-range radar detection systems). The crews of military aircraft are provided with the possibility of emergency escape from the aircraft using a parachute or ejection. On some types of aircraft, to protect crew members from the effects of adverse flight factors, protective equipment is used, for example, altitude-compensating and anti-g suits, etc. ( cm. High altitude equipment). is ensured by a complex of various measures, including: proper standardization of the strength and reliability of the structure of the system and its components; equipping the aircraft with special systems and equipment that increase the reliability of its flight operation; redundancy of vital systems; carrying out the necessary laboratory and bench tests of systems and assemblies, including tests of full-scale structures for strength and fatigue; conducting flight tests to verify the aircraft’s compliance with technical requirements and airworthiness standards; careful technical control during the production process; special selection and high level of professional training of flight personnel; an extensive network of ground air traffic control services; systematically carrying out preventive (routine) work during operation with in-depth monitoring of the technical condition of engines, systems and units, replacing them in connection with the exhaustion of the established resource, etc.- noun, m., used often Morphology: (no) what? airplane, why? airplane, (I see) what? airplane, what? by plane, about what? about the plane; pl. What? airplanes, (no) what? airplanes, why? airplanes, (I see) what? airplanes, what? airplanes, about what? about airplanes... ... Dmitriev's Explanatory Dictionary

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Laboratory work No. 4. Airplane design

4.1. General structure of the aircraft

A modern airliner is a complex system, the creation of which uses the latest achievements of structural mechanics, high technology, radio electronics, and cybernetics. Therefore, first it is better to get acquainted with the design of a simpler machine - a single-seat sports aircraft (Fig. 2) of the monoplane type, i.e. with one wing.

The basis of the structure is the fuselage, or body, which connects all parts of the machine. Its cramped compartments contain equipment: a radio station, batteries, flight and navigation instruments, and often tanks for fuel and lubricants.

In flight, the lift that keeps the car in the air is created by the wing. The wing has a flat bottom surface and a convex top surface, so air flows around the top surface at a higher speed than the bottom. An area of ​​low pressure appears above the wing, which “pulls” the wing, and with it the entire aircraft, upward. This is how lifting force arises. The wing is assembled (Fig. 1) from spars 5 (main longitudinal load-bearing beams), stringers 6 (longitudinal elements), ribs 7 ( cross members) and sheathing.

Rice. 1. Wing diagram:
1 - aileron; 2 - double-slit flap; 3 - brake flap;
4 - wing attachment points; 5 - spar; 6 - stringer; 7 - rib;
8 - slat; 9 - casing

The center section 2 (the middle part of the wing) is attached to the lower part of the fuselage (see Fig. 2), and the right and left consoles 3 (detachable parts of the wing), or load-bearing planes, are attached to the center section. The wing is usually fixedly attached to the fuselage, but sometimes it can rotate relative to the transverse axis of the aircraft (for example, in vertical take-off and landing aircraft) or change its configuration (sweep, span).

At the trailing edge of the wing there are 4 ailerons - small movable planes, with the help of which the pilot regulates the roll of the machine (therefore, the ailerons are sometimes called roll rudders). If you move the control stick to the left, the left aileron will go up, the right aileron will go down, and the plane will roll to the left. If you move the stick to the right, the right aileron will go up, the left aileron will go down, and the car will roll to the right.

On the wing (see Fig. 1) there are flaps 3 and flaps 2. These are downward deflecting surfaces that are designed to increase the stability and controllability of the machine during takeoff and landing. When taking off, they are released at a small angle, and when landing (to reduce speed) - completely.

Propeller 6 (Fig. 2), or propeller (English propeller, from Latin propello - “drive”, “push forward”), is rotated by the aircraft engine. The propeller captures air and throws it back, creating thrust that pushes the car forward. When moving, a lift force is generated on the wing. The pilot adjusts the engine speed depending on the flight mode.

In the rear part of the fuselage there is a fin 7, a rudder 9, a stabilizer 8 and an elevator 10. All together these elements make up tail unit. It is necessary for the plane to be stable in flight - not to nod off, not to fall to the right or left, not to sag on its tail. To a certain extent, the tail unit can be compared to scales. I put the right weight at the right moment - and the scales balanced. Only for the pilot, such “weights” are the rudders, with the help of which he changes the magnitude of the aerodynamic forces acting on the tail.

The steering wheel is deflected using foot pedals. “Gave your right foot” - the rudder deviated to the right, and the plane turned in the same direction. “Gave your left leg” - the plane turned left.

The elevator is sometimes also called the depth control. When the control stick is “taken over,” the rudder tilts up and the plane lifts its nose. If it is “given away from itself,” the rudder is tilted down and the plane descends. A steep descent is called a dive, a gentle descent is called gliding.

On the ailerons, elevator, and rudder of most aircraft there are small deflectable planes called trim tabs (see Fig. 3). The trimmer is used in steady flight conditions to keep the rudders in a deflected state for a long time.

Rice. 2. Design of a sports aircraft:
1 - fuselage; 2 - center section; 3 - wing; 4 - aileron; 5 - motor;
6 - propeller; 7 - keel; 8 - stabilizer;
9 - steering wheel; 10 - elevator; 11 - cabin;
12 - chassis; 13 - sectional view of the cabin with the instrument panel

The controls themselves (handle, pedals, engine control lever) and instruments are located in the cockpit. The top of the cabin is closed with a folding transparent cap, which is commonly called lantern.

And finally, an airplane cannot do without a landing gear (French chassis, from Latin capsa - “box”): on it the airplane takes off during takeoff, rolls after landing, and moves around the airfield. In flight, the landing gear creates aerodynamic drag and reduces speed. Therefore, almost all modern aircraft are built with retractable landing gear. In the air, the wheels and struts are retracted into special compartments - domes, located inside the fuselage or center section, sometimes - the wing (see Fig. 5). The weight of the landing gear structure is about 4 - 7% of the aircraft's weight.

All elements of a sports aircraft presented in the figure are found in airliners (Fig. 5) and on modern fighter aircraft (Fig. 3). These are the basic elements of any aircraft. True, many modern large machines do not have a propeller, since they use turbojet engines (will be studied in laboratory work No. 5).

Rice. 3. Diagram of the MiG-15 aircraft

Rice. 4. Ejection seat

Rice. 5. Turbojet passenger aircraft:

fuselage: 1 - fuselage; 2 - radar fairing; 3 - cockpit canopy;

wing: 4 - center section; 5 - detachable part of the wing (GLASSES); 6 - slats; 7 - aileron;

8 - aileron trimmer; 9 - flaps; 10 - shields;

vertical tail: 11 - keel; 12 - steering wheel; 13 - steering trimmer;

horizontal tail: 14 - stabilizer; 15 - elevator;

16 - elevator trimmer;

chassis: 17 - front landing gear; 18 - main landing gear;

power point: 19 - engines; 20 - air intake

So, let's summarize. The main parts of the aircraft structure are:

The wing creates lift when the aircraft moves. Ailerons (roll rudders) and wing mechanization elements (slats, flaps, flaps) are installed on the wing.

The fuselage serves to accommodate the crew, passengers, cargo and equipment. Structurally, the fuselage connects the wing, tail, sometimes the landing gear and the power plant.

The landing gear is intended for takeoff and landing, as well as for moving the aircraft around the airfield. Airplanes can be equipped with wheeled landing gear, floats (on seaplanes), skis and tracks (on cross-country aircraft). The landing gear can be retractable in flight or non-retractable. Aircraft with retractable landing gear have less drag, but are heavier and more complex in design.

The tail is designed to ensure stability, controllability and balancing of the aircraft in flight.

4.2. Aircraft classifications

1. As intended.

Civil and military aircraft are distinguished by purpose.

TO civil aircraft include:

Transport (passenger, cargo-passenger, cargo),

Sports, record (for setting records for speed, rate of climb, altitude, flight range, etc.), educational,

Tourist,

Administrative,

Agricultural,

Special purpose (for example, for rescue work, remote-controlled),

Experimental.

Rice. 6. Classification of passenger aircraft

Military aircraft designed to engage air, ground (sea) targets or perform other combat missions. They are divided into:

Fighters - for air combat,

Bombers - for destroying objects behind enemy lines and for bombing troops and fortifications,

Scouts,

Transport,

Communication aircraft,

Sanitary.

2. By design.

The classification of aircraft by design is based on external features:

Number and location of wings,

The shape and location of the plumage,

Engine location,

Chassis type,

Fuselage type.

A schematic classification of aircraft by design is shown in Fig. 7.

Rice. 7. Main types of aircraft

Depending from the number of wings distinguish:

Amphibians (seaplanes equipped with wheeled landing gear).

By engine type airplanes are distinguished:

Propeller,

Turboprop,

Turbojet.

When choosing a location for installing engines, their number and type, take into account:

The aerodynamic drag created by the engines is

The turning moment that occurs when one of the engines fails

The complexity of the air intakes,

Possibility of servicing and replacing engines,

Noise level in the passenger compartment, etc.

Depending on flight speed airplanes are distinguished:

Subsonic (aircraft speed corresponds to the Mach number M< 1),

Supersonic (1 ≤ M< 5),

And hypersonic (M ≥ 5),

Mach number

M = V/a,

Where V– speed of the oncoming flow (or speed of the body in the flow);

A– speed of sound in a given flow.

The aircraft's power plant consists of:

Aircraft engines,

Various systems and devices:

Air propellers,

Fire equipment,

fuel system,

Starting systems, lubrication,

Air suction systems, changes in thrust direction, etc.

4.3. Aircraft control systems and equipment

Control systems aircraft are divided into:

The main ones are air control systems (elevator, turn rudder, aileron - roll rudder),

Auxiliary – control systems for engines, steering trimmers, landing gear, brakes, hatches, doors, etc.

The aircraft is controlled using a control column or control stick, pedals, switches, etc., located in the cockpit. To facilitate piloting and increase flight safety, autopilots and on-board computers can be included in the control system; control is made double.

In aircraft control systems, to reduce the effort to deflect the rudders, hydraulic, pneumatic or electrical amplifiers (called boosters) are used, as well as servo compensation devices (i.e., auxiliary surfaces of a relatively small area, usually located on the trailing edge of the main air rudder; they deflect to the side , opposite to the deflection of the air rudder; for example, trim tabs).

Aircraft control in cases where the air rudders are ineffective (flight in a very rarefied atmosphere, on vertical take-off and landing aircraft) is carried out by gas rudders (which vary in design: from plates that change the direction of gas flow thrust, to a complex nozzle apparatus).

Equipment aircraft includes:

Instrumentation, radio and electrical equipment,

Anti-icing devices,

High-altitude, household and special equipment,

For military aircraft - also weapons (guns, missiles, aircraft bombs) and

reservation.

Instrumentation, depending on its purpose, is divided into:

Flight navigation (variometers, attitude indicators, compasses, autopilots, etc.),

To monitor the operation of engines (pressure gauges, flow meters, etc.),

Auxiliary (ammeters, voltmeters, etc.).

The aircraft's electrical equipment ensures the operation of instruments, controls, radio, engine starting systems, and lighting. Radio equipment includes:

Radio communication and radio navigation equipment,

Radar equipment,

Automatic take-off and landing systems.

High-altitude equipment is used to ensure the safety and protection of people when flying at high altitudes (air conditioning systems, oxygen supply, etc.).

Household equipment provides convenient accommodation for passengers and crew and their comfort.

Special equipment includes automatic monitoring systems for the operation of equipment and aircraft structure, aerial photography, equipment for transporting the sick and wounded, etc.

4.4. Vertical take-off and landing aircraft (VTOL) and

short take-off and landing aircraft (STOL).

An increase in aircraft flight speeds leads to an increase in takeoff and landing speeds, resulting in the length of runways reaching several kilometers. In this regard, SKVP and VTOL aircraft are being created.

At high cruising speed (600-800 km/h), SVTOLs have a take-off and landing distance of no more than 600-650 m. Reducing the take-off and landing distance is mainly achieved by:

* using powerful wing mechanization,

* boundary layer control (a layer of gas formed at the surface of a streamlined solid body and having a flow speed much lower than the speed of the flow incident on the body),

* using accelerators during takeoff and speed reduction devices during landing,

* deviation of the thrust vector of the main (i.e. main) engines.

Vertical takeoff and landing of a VTOL aircraft is ensured by special lifting engines, either by deflection of jet nozzles, or by turning the main engines, usually turbojet ones.

Typical VTOL schemes are shown in Fig. 9.

Rice. 9. Vertical take-off and landing aircraft

Security questions

1. Name and briefly describe the main parts of the aircraft structure.

2. Tell us about the power structure of the wing (Fig. 1).

3. Tell us about the elements of the control system located on the wing (Fig. 1 and 5).

4. Tell us about the tail of the aircraft (Fig. 3 and 5).

5. Tell us what types of aircraft there are (Fig. 8) and the location of the tail.

6. Explain how the wing is attached to the fuselage (with what – show in Fig. 3 and 5 and about mobility).

7. What types of airplanes are there based on the number and arrangement of wings?

8. Talk about the fuselage of the airplane (purpose, what’s inside, what the canopy is).

9. Explain what types of aircraft there are by engine type and what is taken into account when choosing the installation location, number and type of engines.

10. Tell what types of airplanes there are according to the method of engine arrangement.

11. Tell us about the aircraft landing gear (purpose, weight, where it is located during the flight).

12. Tell us what types of aircraft there are by landing gear type.

13. Talk about the purpose and classification of civil aircraft.

14. Tell about the purpose and types of military aircraft.

15. Name what classifications of aircraft there are by design. Tell us in more detail about one of the classifications (as assigned by the teacher).

16. Write down and explain the formula for the Mach number. What types of airplanes are there depending on their flight speed?

17. Describe the aircraft control system (types, how the crew influences it, what is installed to improve flight safety)?

18. What is used to reduce the effort to deflect the rudders of an airplane? Tell us when air rudders are ineffective, and what is done in this case?

19. List the equipment available on the aircraft.

20. Talk about instrumentation, high-altitude and household equipment.

21. Talk about special and electrical equipment.

22. Tell us about VTOL and SKVP. Why is there so much interest in them at the moment?

23. Tell us about typical VTOL designs (Fig. 9).

24. Explain the purpose and operating principle of the ejection seat, and the pilot’s ejection diagram.

25. Describe the design of the aircraft according to Fig. 3.

Lecture 1

The main parts of an aircraft are the wing, fuselage, tail, landing gear and power plant.

A wing is the load-bearing surface of an aircraft, designed to create aerodynamic lift.

The fuselage is the main part of the aircraft structure, which serves to connect all its parts into one whole, as well as to accommodate the crew, passengers, equipment and cargo.

The tail is a load-bearing surface designed to provide longitudinal and directional stability and controllability.

Landing gear is an aircraft support system used for takeoff, landing, movement and parking on the ground, the deck of a ship or on the water.

The power plant, the main element of which is the engine, serves to create thrust.

In addition to these main parts, the aircraft has a large number of different equipment. It is equipped with main control systems (control of control surfaces: ailerons, elevators and rudder), auxiliary control (control of mechanization, retraction and release of landing gear, hatch doors, equipment units, etc.), hydraulic and pneumatic equipment, electrical equipment, high-altitude , protective equipment, etc.

Flight, geometric and weight characteristics, general layout, equipment used, as well as the design of individual parts are largely determined by the purpose of the aircraft.

Classification of aircraft according to the scheme

The classification of aircraft according to the scheme is carried out taking into account the relative position, shape, number and type of individual components that make up the aircraft.

The aircraft layout is determined by the following features:

1) the number and location of wings;

2) type of fuselage;

3) the location of the plumage;

4) chassis type;

5) type, number and location of engines.

It is possible to fully characterize the design of an aircraft only on the basis of all these five features. Classification according to only one or several of them cannot give a complete picture of the scheme.

Based on the number of wings, all aircraft are divided into biplanes (Fig. 1, a) and monoplanes, and the latter, depending on the relative position of the wing and fuselage, are divided into low-wing (Fig. 1, b), mid-wing (Fig. 1, c) and high-wing ( Fig.1, d).

Rice. 1. Airplane diagrams by number and location of wings

Based on the type of fuselage, aircraft are divided into single-fuselage (Fig. 2, a) and double-boom (Fig. 2, b).

Fig.2 Airplane diagrams by fuselage type.

The location of the tail on the aircraft largely determines the so-called aerodynamic design of the aircraft, which depends on the number and relative position of its load-bearing surfaces.

On this basis, modern monoplane aircraft are divided into three schemes: a normal or classic scheme (Fig. 3, a), a scheme with a front horizontal tail - a "canard" type scheme (Fig. 3, b) and a scheme without horizontal tail - a scheme “tailless” (Fig. 3, c). Very heavy tailless aircraft can be made according to the “flying wing” design (Fig. 3, d).

Rice. 3. Airplane diagrams by empennage location

Depending on the take-off and landing conditions, aircraft can have a wheeled landing gear (Fig. 4, a), a ski landing gear (Fig. 4, b), or a float landing gear (Fig. 4, c). For seaplanes, the fuselage can also serve as a boat (Fig. 4, d). There are mixed designs: wheeled ski chassis, amphibious boat.

Rice. 4. Aircraft diagrams by landing gear type

Piston and gas turbine engines are used as the main engines on modern aircraft. The most widely used engines at present are gas turbine engines, which, in turn, are divided into turboprop, turbofan, turbojet, turbojet with afterburner and turbojet bypass.
The choice of the type of engines, their number and location is determined to a large extent by the purpose of the aircraft and has a significant impact on its design. In Fig. Figure 5 shows typical layouts of engines on an aircraft.

Fig.5. Typical engine layouts on an aircraft:
a, b – in the fuselage; c – on the rear part of the fuselage; d, e, f - on the wing.

Even the shortest flight always causes a lot of anxiety for the traveler. And this is not surprising, because many people still experience real fear of flying in the sky and believe that they definitely cannot be comfortable. However, experienced travelers know exactly how to make their few hours in the air as enjoyable as possible. An important role in this matter is played by what seats you will sit in during the flight. We think that no one will like to travel sandwiched between two well-fed neighbors or to spend the entire flight watching people crowding around your seat, wanting to get to the toilet. Therefore, after the cost of the ticket and the reliability of the airline, you should pay attention to which seats on the plane are best to choose. Of course, there is not always unity on this issue, because much depends on the passenger’s build, the company with which he is flying, as well as personal preferences and the brand of the airliner. But we will try to give you general recommendations on which seats are best to take on the plane if you want your air travel to be smooth.

Flight class

What are the best seats on a plane? This question can be answered in different ways, but most passengers know for sure that the comfort of a flight directly depends on what class you travel in. This nuance directly affects many travel characteristics: seat comfort, level of service, quality and choice of food. This is especially important when your flight takes more than four hours and comfort becomes the most important condition. Therefore, if you are thinking about which places to go, try to choose a higher flight class when planning your trip.

Modern air carriers offer their customers the following travel options:

• economy class;
• business class;
• first class.

Each of the options listed has its pros and cons. Therefore, before finding out, for example, which seats on an economy class plane are best, we will give a brief description of each class of flights.

What to expect from a budget trip?

Most passengers travel by air this way. After all, economy class tickets always have a low cost and are available to the general mass of tourists. Those who often fly by plane compare such a trip in terms of comfort with a trip on a bus. The airliner's cabin is equipped with reclining seats; the distance between the seats will allow passengers of average height and build to stretch out their legs and sit comfortably. You will definitely be fed during the flight, and many airlines also give children gifts consisting of coloring books, pencils and various games that help while away the flight.

However, keep in mind that economy class does not boast many amenities. For many passengers, the distance between the seats and rows seems too small, and they cannot sit comfortably. This becomes a serious problem when the flight lasts several hours. In addition, traveling in economy class imposes some restrictions on baggage allowance. Recently, major airlines have been providing seats in the most budget class flights increased comfort. They usually cost a little more than regular ones, but the demand for such tickets shows that they are very popular among tourists.

Flying in business class

Traveling in business class is extremely comfortable; there are comfortable seats that you can fully recline and relax during a long and tiring flight. In addition, passengers receive delicious à la carte dishes and a wide range of alcoholic drinks. Each chair is equipped with such pleasant little things as, for example, sockets to recharge laptops and smartphones.

For many tourists, the answer to the question “which seats on the plane is best to choose for a pleasant and memorable trip” is obvious - naturally, in business class.

Most expensive trip

Not every airline can boast of having first class seats on board. It is one of the most comfortable of all the above, but also the most expensive at the same time. Travelers who can afford this type of flight receive a host of benefits, including a dedicated check-in counter and preferential boarding.

It is worth noting that first class flights will seem the most convenient to tourists, but, unfortunately, not every passenger can afford such a luxury. Therefore, in further sections of the article we will try to find out which seats on the plane are best to choose for a comfortable and enjoyable trip.

Porthole seats

Many passengers think the best places chairs located near the porthole. Undoubtedly, they have many advantages, but they are not suitable for all travelers.

You can choose such places if you plan to get some sleep during the flight, because no one will disturb your sleep by sneaking to the toilet. It is quite convenient to be at the porthole for those who plan to occupy themselves with reading or working on a laptop. There is enough light here, so your eyes won’t get tired, and you can spend your flight in comfortable conditions.

However, keep in mind that it will be difficult to go to the toilet from here - you will have to constantly apologize and disturb other passengers nearby.

Is it comfortable to fly on the aisle?

For those trying to figure out which airplane seats are best for restless travelers, consider aisle seats. They allow you to get up at any time, give you the opportunity to stretch out comfortably, and also go to the toilet without thinking about disturbing your sleeping neighbors, for example. It's nice that passengers sitting near the aisle are practically the first to go down the stairs after the airliner lands. And therefore, they have a chance to complete all the documents at customs without unnecessary fuss and receive their luggage before other tourists.

But don’t forget about the disadvantages that aisle chairs have. It will be quite difficult for you to doze off or just relax, because other passengers and flight attendants are constantly walking between the rows. In addition, be prepared to get up from your comfortable chair every time your neighbors decide to go to the toilet or just stretch their legs.

Places in the center

Most articles that give advice on which seats to reserve on an airplane at check-in list center seats as the least suitable option of all. However, in reality it all depends on who is traveling. For example, for families with children, these places are the most convenient for placing a child. Judge for yourself, he will feel both parents, and during sleep he will be able to stretch out, sitting on the laps of mom and dad. Therefore, many families try to occupy three seats next to each other when checking in for a flight.

But people traveling alone will not be very comfortable sitting in the center seat surrounded by two strangers.

Emergency exits: pros and cons of places

Some passengers mistakenly believe that emergency exit seats are the best and are often disappointed with their flight. After all, in fact, the seats at emergency exits on an airliner have their own classification. You need to know this when checking in for your flight and choosing seats on board.

The lucky ones are those travelers who managed to get into a row of seats between two emergency hatches. There is plenty of room here even for passengers taller than average, and you can fully recline the seat back without irritating passengers sitting behind you. It is also quite comfortable to sit in the seats that are located in front of the emergency exit. They have increased row spacing, and many airlines even leave space behind by removing a row of seats. However, keep in mind that such places usually do not accommodate women, children and the elderly, who will not be able to act calmly in a critical situation. Do not forget that airline regulations strictly prohibit placing hand luggage near the emergency hatch.

Places after emergency exits are considered the most undesirable in this category for a long journey. The seats are firmly fixed in one position, so the flight will be extremely unpleasant.

Seats in the nose of an airliner

The choice of such a place for air travel in many cases is completely justified. Passengers seated at the front of the aircraft will receive drinks and food first during lunch. They don’t have to worry that the flight attendant will run out of juice or mineral water. In addition, they are the first to leave after landing, but this is where mothers and babies are often placed. A baby cradle can be conveniently secured in the front part of the cabin, so preference is given to this category of passengers when checking in. If you don't tolerate traveling surrounded by crying babies or plan to work during the entire flight, then try to choose other seats.

Tail section of an airliner

The seats in the rear have long been recognized as the most uncomfortable. There are always crowds of people here and there is practically no choice of hot food, and after landing passengers will have to leave after all other travelers.

However, often the tail compartment is not completely filled, so it becomes possible to comfortably sit on three chairs at the same time and get a good night's sleep. According to statistics, during the crashes, about seventy percent of the survivors were sitting in the tail of the plane.

First rows of seats

Some passengers deliberately choose seats in the front rows of seats. They have a lot of advantages: no one will recline the seat back in front of your nose, and a wall or partition in front creates a certain atmosphere of privacy even in a full aircraft cabin.

The best places to travel with children

If you are traveling with a full group, then information about which seats on the plane are best to choose - after all, flying with a child is quite difficult, you must admit - is not an empty phrase for you. You will find this section of the article useful.

Usually the first rows of seats are considered the most comfortable. In them, your child will not disturb other passengers, for babies there is the opportunity to secure a cradle, the choice of dishes is the widest, and turbulence is least felt.

Most often, the airline representative who checks in for the flight takes into account the fact that parents and children must sit next to each other. However, it would not be superfluous to remind about this, because in the process of work, some employees may not pay attention to the age of the child.

Try to get seats in the front part of the cabin, because if the plane is not fully loaded, you can always move to the back and put your baby to sleep in the three free seats. Otherwise you will still have good places in the front rows, where it is quite comfortable with a child.

What are the best seats on an Airbus?

General advice on choosing seats in the cabin may not always be effective, because they do not take into account the structural features of the airliner. This nuance must be taken into account when thinking about which seats on the plane are best to choose. Airbus, for example, is a fairly popular aircraft model among Russian airlines. It has several modifications, each with its own characteristics.

The Airbus 319-100 airliner provides for the sale of tickets in two categories: business and economy. For passengers of the second group, the most comfortable seats will be in the third row. They are the first and are separated from the other cabin by a curtain, this makes it possible to sit very comfortably while traveling. The tenth row is often called “seats of increased comfort”, because in front of them there is an emergency exit and travelers are accommodated with greater comfort.

The interior configuration of the Airbus 320 aircraft suggests that the most comfortable seats are those located in the third, tenth and eleventh row. The economy countdown starts from the third row seats and there is a partition in front of them. This prevents the seat in front from reclining due to its absence. The tenth row is distinguished by a wide aisle from one row to another. However, do not forget that the position of the chairs is securely fixed, so you can only comfortably stretch your legs. The eleventh row can be considered the most suitable for long flights; the backrests recline here, and the distance in front is quite enough for even a very tall passenger to sit comfortably.

What are the good seats on a Boeing plane?

These airliners are also often used by Russian air carriers. A popular model is Boeing. What seats on the plane would be better to choose if you were flying on board this model? We will reveal this secret to you now.

For passengers, there is serious confusion due to the slightly different interior configurations of these airliners. In one version there is a row with two chairs. Here the most desirable seats will be in the fourth, thirteenth and fourteenth rows. The fourth row begins the countdown in the economy class cabin. There will be a partition in front of passengers that does not reach the floor. This allows travelers to sit in any position convenient for them. Flight attendants start serving food from these places, so you won’t have any problems choosing. The thirteenth row is not suitable for everyone, because behind it there is an emergency exit, which means the transformation of the seat is impossible. However, there are only two seats and plenty of legroom. The fourteenth row has the most important advantages over other seats: reclining seat backs and an increased passage between the rows.

The second version of the interior configuration is identical to the first, but here the numbering is shifted by one and there are no rows with two seats. Therefore, similar to the previous description, the seats in the fourth, twelfth and thirteenth rows will be comfortable here.

We hope that after reading our article you will be able to easily check in for your flight via the Internet and choose the most comfortable seats for yourself and your family. Enjoy your flight and have a soft landing!