What is the front part of the plane called? Aircraft design: basic elements

This is for fun... Su-26

This is a short article about something that everyone seems to have seen, but not everyone imagines it.

What is an airplane anyway? This is an aircraft designed to move various cargo and people through the air. The definition is primitive, but true. All airplanes, no matter how romantic they may look, are designed to work. And only sport aviation exists solely for flight. And what a flight :-)!

What helps an airplane fulfill its purpose? What makes an airplane an airplane? Let's name the main ones: fuselage, wing, tail, takeoff and landing device.

Design elements and controls

Separately, you can also highlight the power plant, that is, engines and propellers (if the aircraft is propeller-driven). The first four elements are usually combined into one unit, called a glider in aviation. It is worth noting that all of the above refers to the so-called classical layout scheme. After all, in fact, there are several of these schemes. In other schemes, some elements may not be present. We will definitely talk about this in other articles, but for now we will pay attention to the simplest and most common, classical scheme.

Fuselage. This is, so to speak, the basis of the aircraft. It, as it were, collects all the other elements of the aircraft’s structure into a single whole and is a container for aviation equipment (avionics) and payload... The payload is, of course, the actual cargo or passengers. In addition, fuel and weapons (for military aircraft) are usually located in the fuselage.

But this is for work... TU-154

Wing. Actually, the main flying organ :-). Consists of two parts, consoles, left and right. The main purpose is to create lift. Although in fairness I will say that on many modern aircraft the fuselage, which has a flattened lower surface (this is the same lift force), can help in this. On the wing there are controls for rotating the aircraft around its longitudinal axis, that is, roll control. These are ailerons, as well as organs with the exotic name spoilers. There, on the wing, there is the so-called. These are flaps and slats. These elements improve the takeoff and landing characteristics of the aircraft (takeoff and landing length, takeoff and landing speeds). On many aircraft, fuel is also located in the wing, and on military aircraft, weapons are located.

Well, where is the fuselage?... Su-27

Tail. Not less important aircraft structural element. Consists of two parts: keel and stabilizer. The stabilizer, in turn, like the wing, consists of two consoles, left and right. The main purpose is flight stabilization, that is, they help the aircraft maintain the flight direction and altitude that were originally assigned to it, regardless of atmospheric influences. The keel stabilizes the direction, and the stabilizer stabilizes the height. Well, if the crew piloting the airliner wants to change the flight course, then for this purpose there is a rudder on the fin, and to change the altitude on the stabilizer, accordingly, there is an elevator.

I will definitely touch on my favorite topic about concepts. It is incorrect to say “tail” when referring to the keel, as can often be heard in non-aviation environments. Tail is generally a specific word and refers to the rear part of the fuselage along with the tail.

There is such a chassis... MIG-25

Another important part, an element of the aircraft’s design (although there are probably no unimportant ones :-)). This is a take-off and landing device, and on a simple landing gear. Used during takeoff, landing and taxiing. The functions are quite serious, because every plane, as you know, is simply obliged to “not only take off well, but also land extremely successfully” :-). The chassis is not just a wheel, but a whole complex of very serious equipment. The cleaning and release system alone is worth it... Here, by the way, the well-known ABS is present. It came to our cars from aviation.

And sometimes such a chassis... AN-225 "Mriya"

I also mentioned the power plant. The engines can be located inside the fuselage, or in special engine nacelles under the wing or on the fuselage. These are the main options, but there are also special cases. For example, an engine in the root of the wing, partially recessed into the fuselage. Sounds complicated, doesn't it? But it's interesting. In modern aviation, in general, a lot of intricate things have appeared. Where, for example, is the pure fuselage on a MIG-29 or Su-27 aircraft. But he is not there. Technically, it certainly stands out, but externally... Solid wing, engines and cockpit :-).

Well, that's probably all. I have listed the main ones. It turned out a little dry, but that’s okay. We'll talk about each of these elements later, and then I'll go wild :-). After all, the variety of layouts, designs and composition of equipment is very large. These include different general layouts and different layouts of the tail unit, wing, different designs and arrangements of the landing gear, engines, engine nacelles, etc. From all this diversity, we get a lot of all kinds of aircraft, both unique in their capabilities and incredibly beautiful, and mass-produced, but still beautiful and attractive.

Bye:-). Until next time...

P.S. How did I get separated, huh?! Well, just like talking about a woman :-)…

Photos are clickable.

Wrote in July 26th, 2014

It is the world's largest twin-engine jet passenger aircraft. The Boeing 777 set an absolute range record for passenger aircraft: 21,601 thousand km! Boeing 777 (“Triple Seven” or “three sevens”) - this aircraft was developed in the early 1990s, made its first flight in 1994, and has been in operation since 1995. The Boeing 777 was the first commercial airliner to be designed 100% by computers. And this is the safest long-haul airliner in the history of aviation!

I flew on three sevens only once - from Dubai to Male with Emirates airlines and then I was surprised to learn that they saved a lot on the layout of the economy class cabin, we will put one additional seat in a row, reducing the width of the others! In this report I will talk about the history of creation, design features and show the passenger cabin of the largest operator of this type of aircraft in Russia.

History of creation:

In the mid-1970s. The three-engine 777, which was intended as a competitor to the McDonnell Douglas DC-10 and Lockheed L-1011. This aircraft was conceived as a modified version of the 767 with a redesigned wing and tail section. It was planned to create two main options: a short-haul aircraft, which would be capable of carrying up to 175 passengers over a distance of 5,000 kilometers, and an intercontinental airliner, carrying the same number of passengers over a distance of up to 8,000 kilometers.

Work on twin-engine aircraft soon began, but the 777 project was frozen, as difficulties arose with the design of the tail section of the aircraft, and the company also decided to focus on the more commercially promising 757 and 767. As a result, when both aircraft began to roll off the assembly line, it became Clearly there is a missing link in Boeing's aircraft line. There was an urgent need to have an aircraft that would be in the niche between such machines as the Boeing 767-300ER and Boeing 747-400.

At first, Boeing planned to simply modify the 767, resulting in the so-called 767-X concept. It was in many ways similar to the 767, but had a longer fuselage, a larger wing and could carry about 340 passengers over a distance of up to 13.5 thousand kilometers.

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But airlines were not impressed with the new aircraft. They wanted an aircraft capable of flying shorter distances and with a cabin configuration similar to the Boeing 747, which, in addition, could be changed by adding or removing the required number of passenger seats in a particular class of cabin. Another necessary condition was to reduce operating costs - they would have to be significantly lower than those of the 767. As a result, the original project was heavily redesigned and the twin-engine Boeing 777 was born.

The Boeing 777 was the first commercial airliner to be designed 100% by computers. During the entire development period, not a single paper drawing was released; everything was made using a three-dimensional design system.

Development of the aircraft began in 1990 and the first order was immediately received from United Airlines. In 1995, the first 777 began commercial flights. Currently, the 777-200LR is the aircraft capable of performing the longest passenger flights in the world.

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Modifications:

The 777-200 was the first modification of the aircraft and was intended for Segment A. The first 777-200 was delivered to United Airlines on May 15, 1995. With a range of 5,235 nautical miles, the 777-200 modification was aimed primarily at US domestic carriers. A total of 88 different aircraft of the 777-200 modification were delivered to ten customers. Airbus's competing model is the A330-300.

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The stretched version of the 777-300 was intended to replace the Boeing 747-100 and Boeing 747-200 aircraft. Compared to older versions of the 747, the stretched version has similar passenger capacity and range, but uses a third less fuel and has 40% lower operating costs. The fuselage of the 777-300 is extended by 11 meters compared to the basic modification of the 777-200, which allows it to accommodate up to 550 passengers in a single-class configuration. The modification's maximum range is 6,015 nautical miles, allowing the 777-300 to serve heavily trafficked destinations previously served by the 747.

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777-200ER

Modification 777-200ER (“ER” means Extended Range, increased range). The 777-200ER has increased fuel capacity and maximum take-off weight compared to the 777-200 modification. Intended for international carriers and transatlantic flights, the nf modification has a maximum range of 7,700 nautical miles (14,260.4 km).

777-200LR

The 777-200LR (“LR” stands for Longer Range), a Segment C model, became the world's longest-range commercial airliner in 2006. Boeing called this model the Worldliner, indicating the airliner's ability to connect almost any two airports. The modification set a world record for the longest non-stop flight among commercial airliners - the flight range is 9,380 nautical miles (17,370 km). The 777-200LR modification is designed for ultra-long flights, such as Los Angeles - Singapore or Dallas - Tokyo. The 777-200LR has an increased maximum takeoff weight and three additional fuel tanks in the rear cargo compartment.

777-300ER

The 777-300ER (“ER” stands for Extended Range) is a modification of the 777-300. The modification has beveled and extended wingtips, new main landing gear, a reinforced nose strut and additional fuel tanks. The model's standard GE90-115B turbofan engines are the most powerful jet engines in the world today, with a maximum thrust of 513 kN. The maximum range is 7,930 nautical miles (14,690 km), made possible by increased maximum take-off weight and fuel capacity. The 777-300ER's fully loaded range is increased by approximately 34% compared to the 777-300. After flight tests, the introduction of new engines, wings and an increase in take-off weight, fuel consumption decreased by 1.4%.

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And all the modifications in the visual series:

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A good illustration for comparing scales is the 737 in front. Please note that the diameter of the GE-115B engine installed on the 777 model is only 30 cm less than the width of the Boeing 737 cabin!

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Design elements:

The design of the aircraft's airframe includes the use of composite materials, which account for 9% of the weight of the structure. The interior floor and steering wheels are also made from such materials. The main part of the fuselage has a circular cross-section and at the rear merges into a blade-like tail cone, which houses the auxiliary power unit.

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The airliner also has the largest landing gear and the largest tires ever used on a commercial jet airliner. Each tire on the 777-300ER's six-wheel main landing gear can support 27 tons, which is more than the tire load on a Boeing 747-400!

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The aircraft has three redundant hydraulic systems, of which only one is needed for landing.
In the wing fairing under the fuselage there is an emergency aircraft turbine - a small propeller that extends out of the aircraft in emergency situations to provide minimal power.

The General Electric GE90 engines powering the Boeing 7777 are the largest and most powerful jet engines in aviation history.

And all five Boeing 777-300 of Transaero are equipped with RR211 Trent 892 engines from Rolls Royse:

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Cockpit:

The cockpit is very spacious. The Boeing 777 in all modifications is a long-haul airliner capable of serving non-stop commercial flights lasting up to 18 hours. However, regulations of various aviation regulatory bodies, professional and trade union organizations limit the continuous work time of crew and flight attendants.

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Interior:

The 777 interior, also known as the Boeing Signature Interior, features curved lines, extended overhead bins and indirect lighting. Seat configurations range from 4 abreast in first class to 10 abreast in economy class. The size of the windows - 380x250 mm - was the largest of any commercial airliner until the introduction of the 787.

Each airline's passenger cabin has its own layout. It depends on certain customer requirements, and not on the type of aircraft!
Please note that in economy class, Transaero has one less seat in a row than, for example, Emirates (!) and Aeroflot. This means that the chairs themselves are wider and more comfortable!

Examples of the layout of Boeing 777 -200 and -300 a/k Transaero:

Economy 2-5-2:

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Economy 3-3-3:

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Emirates" - economy 3-4-3

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Aeroflot - economy: 3-4-3

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Let's take a look on board the Boeing 777-300 of Transaero Airlines. EI-UNM flew with Singapore Airlines and was transferred to Transaero in 2012. The interior has been completely updated, with a Lumexis entertainment system installed throughout. The upholstery uses wear-resistant Alcantara material, and the seat manufacturer is the Italian company Aviointeriors.

Imperial class "Transaero":

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Business Class:

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Economy class:

The economy class cabin in red colors is called “economy class”, and the blue one is called “tourist class”. They differ in the pitch of the seats. In economy class - 36 inches, in tourist class - 32 inches.

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Wi-Fi is available on board! I'll have to test it somehow when I fly.

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Visually, the color separation in the interior is pleasing to the eye:

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Kitchen at the rear of the plane:

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And even an installation for uncorking champagne bottles for the Imperial class:

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In total, about 1100 aircraft have been produced at the moment!
Once I photographed the 1000th copy in Dubai:

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Safety:

This airliner is considered the safest aircraft among all long-haul airliners. During its 18 years of operation, the Boeing 777 suffered eight incidents, including one crash and two hijacking attempts. On July 6, 2013, the first plane crash with human casualties occurred. An Asiana Airlines Boeing 777-200ER, flying from Seoul to San Francisco, crashed while landing at San Francisco Airport, hitting the end of the runway with its tail. 2 people died.

Boeing 777 in Russia:

In Russia, the largest operator of Boeing 777 aircraft is Transaero. This company has 14 aircraft in its fleet: 5 Boeing 777-300, 9 Boeing 777-200ER. In addition to Transaero, this aircraft is in the fleet of Aeroflot, Nordwind and Orenair.

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The Boeing 777 has been operated by Transaero for 5 years; in one of the following reports I will talk about its maintenance at the company’s own repair and technical facilities.

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Enjoy your flights!

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I thank the press service of Transaero Airlines and personally Sergei Moryakov for the opportunity to make this report!

Taken from alexcheban in The plane that flies the farthest!

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

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

Airplane fuselage

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

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

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

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

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

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

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

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

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

Wing design

A wing is one of the main structural elements of an aircraft, providing lift for flight and maneuvering in air masses. Wings are used to accommodate take-off and landing devices, a power unit, fuel and attachments. The operational and flight characteristics of an aircraft depend on the correct combination of weight, strength, structural rigidity, aerodynamics, and workmanship.

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

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

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

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

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

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

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

Aircraft engines

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

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

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

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

Controls and signaling

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

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

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

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

1. Additional control used during takeoff or landing modes.

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

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

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

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

Takeoff and landing systems 2280

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

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

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

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

Video

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

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.

Based on this feature, 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 engine layouts 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.

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 the 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 plane, upward. This is how lifting force arises. The wing (Fig. 1) is assembled from spars 5 (main longitudinal load-bearing beams), stringers 6 (longitudinal elements), ribs 7 (transverse elements) and skin.

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 cabin is closed from above by a folding transparent hood, 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. Airplanes 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 relate:

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 electric 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 air rudders are ineffective (flight in a highly 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

Control 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 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. Tell us 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 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.