Tu 244 and new supersonic aircraft projects. Supersonic passenger plane: from the president’s idea to reality
Supersonic aviation in the Soviet Union had enormous potential. The legendary Tu-144 airliner became the first supersonic passenger aircraft in the world. And now, decades later, Russia can once again return promising air passenger transportation technology to the air. This event is evidenced by the resumption of activity on the Tu-244, a revolutionary project of the 1970s that was never realized in its time.
Work on the creation of a second-generation supersonic airliner began back in 1971 at the Tupolev design bureau. Taking the experience of developing the Tu-144 as a basis, in the next decade it was planned to launch a fundamentally new supersonic aircraft Tu-244.
The project was approached with the utmost seriousness. The calculation included not only design features, but also the economic competitiveness of the aircraft, environmental safety and the level of passenger comfort. Given the significantly higher flight speed compared to subsonic airliners, it was possible to build much less Tu-244, but the commercial efficiency would be greater.
In turn, increased noise, greater emissions of harmful substances and damage to the Earth’s ozone layer were significantly higher than that of conventional jet aircraft. All these factors had a negative connotation for the future project. However, in those years, much less attention was paid to environmental safety than now. The Tu-244 was developed in at least two versions: a gigantic 360-ton machine with a passenger capacity of more than 300 people and a smaller aircraft weighing about 275 tons. The technology of both prototypes relied heavily on new, innovative engines that were in the early stages of production in the 1970s.
The first approved model was the SPS-1 model, developed in 1973. The liner was equipped with four engines with a total thrust of 37.5 kgf. When reaching a cruising speed of 2400 km/h, the aircraft could cover a distance of 8000 kilometers at an altitude of up to 20 thousand kilometers. At the same time, the SPS-2 prototype was considered, which used liquid hydrogen engines.
The development of SPS-2 was personally led by Andrei Tupolev. An important difference between the Tu-244 and its predecessor, the Tu-144, was the absence of a downward tilting nose and minimal glazing in the cockpit. Ultimately, in 1985, the Tupolev team settled on a 275-ton prototype with an engine take-off weight of 24 thousand kgf. According to the website, the use of variable cycle engines made it possible to fully realize the operation of the power unit in different flight modes.
It would seem that the release of a promising airliner was just around the corner, but the approaching restructuring brought to naught all grandiose plans. Full technical information about the future project became available to the public in 1993 at the Paris Air Show. And that’s all... For more than twenty years no news was heard about the Tu-244, and only in 2014 information about a possible revival of the project began to appear on the Internet.
On January 29, 2019, work on the creation of a domestic second-generation supersonic airliner was officially resumed. Currently, the Tu-244 is at the development stage, which is planned to be completed in a few years. According to sources, the first prototype will take to the skies in 2025. Certainly, appearance The new Tu-244 will be somewhat different from the Soviet developments of thirty years ago, but in technical terms the airliner will suffer virtually no changes.
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In the very near future, Russia can once again return supersonic passenger airliners to the skies, and an excellent help for this is the continuation of work on the final creation of the Tu-244 supersonic jet aircraft, developed back in Soviet times.
According to the most modest official statements, the Tu-244 aircraft will most likely be put into operation in 2025, that is, literally in 10 years. Of course, it is expected that its appearance will be somewhat different from the developments of Soviet aircraft manufacturers, but in general, the aircraft will remain as intended.
The Tu-244 supersonic jet aircraft will have 4 turbojet engines, allowing the aircraft to be lifted to an altitude of up to 20 thousand meters, which will significantly relieve the load on aircraft used this moment directions. However, along with this there is a need for a long runway, but this task is quite feasible and relatively inexpensive, especially since a number of airports can already accept such aircraft.
The technical characteristics of the supersonic airliner are also very modern, although the work was carried out back in 1971. The estimated speed of the aircraft should reach 2175 km/h, but the possibility cannot be ruled out that it will be increased to 2500 km/h. The estimated number of passengers that can be accommodated on board the airliner is about 300 people, which, in principle, corresponds to modern trends civil aviation. The Tu-244 supersonic jet aircraft will have huge size– its length will be about 88 meters, its wingspan will be 45 meters, and its height will be about 15 meters. However, at the moment, aircraft engineers are solving two very important problems that will truly make the aircraft truly modern:
Increasing the flight range, since Soviet engineers considered that a flight of 9,200 kilometers would be optimal, but in reality, this is very little;
Reducing the fuel consumption of the aircraft, since we recall that it was precisely for this reason that the whole world abandoned the use of jet airliners.
If the first problem is solved relatively easily, then the second one may have a number of difficulties. However, work on the implementation of this project is underway, and it is quite possible that in the very near future we will be able to see the Tu-244 supersonic passenger aircraft in the sky.
Benefits of using reactive supersonic airliners are undeniable:
Flights between regions, states and continents will become as fast and comfortable as possible, as passengers will be able to fly to their destination three or more times faster;
Due to the large capacity of the aircraft, it will be possible to slightly reduce the cost of air travel;
The ease of aircraft maintenance will increase, since one large aircraft will be serviced much faster than two small airliners.
In 1973, the OKB prepared a preliminary design of the SPS-2, which received the designation Tu-244. When developing the project, the main goal was to obtain a plane that would be competitive with respect to the long-haul subsonic passenger aircraft that were in operation and in development. The competitiveness of such an aircraft (compared to a conventional subsonic airliner) had to be ensured by economic efficiency, environmental acceptability and convenience for passengers. At the same time, economic efficiency (lower unit costs) was determined by the greater productivity of the SPS-2 than that of subsonic aircraft (due to speed), which was supposed to ensure the transportation of growing passenger traffic by a smaller number of aircraft compared to the fleet of subsonic aircraft. The difference in the cost of the required quantity of both passenger aircraft and in the costs of their operation should have compensated for air carriers the increase in fuel costs associated with the use of less economical SPS-2. The environmental acceptability of SPS-2 largely determined the success or failure of the project. The solution to this problem was associated with determining the level of environmental impact of SPS-2 on environment(sonic boom, noise in the area, emissions of harmful substances, including the impact of emissions on the ozone layer). All these problems, to one degree or another, were present during the creation of the SPS-1, but at the time of their initial design (the first half of the 60s), they were not treated as major ones. The main task was to create and put into operation a really flying ATP. Work on SPS-2 has been and is being carried out at the Design Bureau for 25 years. Over the years, several different Tu-244 projects were prepared, differing from each other in aerodynamic layout, specific design solutions for the airframe, power plant and flight performance data. The main difference between the prepared SPS-2 and SPS-1 projects was a higher level of aerodynamic characteristics of the aircraft, greater efficiency of power plants, as well as an increase in their weight and size parameters, while ensuring transportation more passengers over long flight distances. Work on SPS-2 at the OKB was directly supervised by A.A. Tupolev for many years. Currently, the Chief Designer on the SPS-2 topic is A.L. Pukhov, technical supervision for work on the Tu-244 is provided by M.I. Kazakov.
One of the first projects of the Design Bureau of the Tu-244 aircraft was the 1973 project with four engines with a take-off thrust of 37,500 kgf with a specific fuel consumption in supersonic cruising mode of 1.23 kg/kgf x hour. According to the project, the aircraft's take-off weight reached 360 tons, the payload was 30 tons (various passenger cabin layouts could accommodate from 264 to 321 passengers). The wing area reached 1100 m2. At a cruising speed of 2340 km/h, the aircraft with a normal commercial load should have had a flight range of 8000 km. In its scheme, this project was a further development of the Tu-144. The main efforts in developing the aerodynamic configuration were aimed at increasing the Kmax values in order to obtain a given flight range. For this purpose, the relative midsections of the fuselage and engine nacelles were reduced on the aircraft, a wing of increased area and aspect ratio was used, mechanization of the leading edge of the wing was used in the form of deflectable nose parts (deflection was provided for in subsonic modes), separate engine nacelles with axisymmetric air intakes were located behind the line of maximum wing thickness, optimized the shape of the wing surface taking into account interference with engine nacelles, etc. As a result, when purging the models, it was possible to obtain cruising Kmax = 8.75-9.0 at M = 2.2 and in subsonic mode Kmax = 14.8.
At the end of 1976, a decision was made by the military-industrial complex under the Council of Ministers of the USSR on SPS-2, which determined the development procedure and basic data of the Tu-244. According to this decision, at the first stage it was planned to design SPS-2 of relatively small size with a take-off weight of 245-275 tons, a wing area of 570-750 m 2 and with engines with a take-off thrust of 22500-27500 kgf. In the future, it was planned to transition to SPS-2 of larger dimensions. By 1985, the Design Bureau prepared a technical proposal for the Tu-244 with four variable cycle engines (VDC) with a take-off thrust of 24,000 kgf. The project envisaged the creation of a Tu-244 with parameters slightly larger than the Tu-144D: take-off weight 260 tons, wing area 607 m2, number of passengers - 150-170. Estimated flight range 7000-10000 km. The design cruising aerodynamic quality at supersonic speed for the project was determined to be 8.65. A feature of the project was the use of DIC engines in combination with air intakes that were shortened compared to the Tu-144. The use of DIC made it possible to optimize the operation of the power plant to the greatest extent in various flight modes and made it possible to perform highly economical subsonic flight over areas with high population density.
A project with liquid hydrogen engines was being worked on.
In 1993, two Tu-144Ds were converted into flying laboratories as part of work on the second generation ATP.
The technical complexity and increasing cost of programs to create SPS-2 forced leading aircraft manufacturing firms in the USA, Great Britain, France, Germany, Italy, Japan and the USSR (Russia) to coordinate their research on SPS-2, primarily in the field of environmental impact, starting from the late 80s , as well as in assessing humanity’s need for ATP and determining their rational parameters (it should be noted that similar cooperation was carried out before: starting from the mid-60s, cooperation was established between the USSR and France, although in limited quantities, on some problems of creating SPS-1). In the early 90s, in order to solve the problems of creating SPS-2, the so-called “Group of Eight” was formed at the international level, which included the companies Boeing, McDonnell-Douglas, British Aerospace, Aerospatiale, Deutsche Aerospace Airbus (DASA), Alenia, Association of Japanese Aviation Corporations and JSC ASTC named after A.N. Tupolev.
Based on previous studies on ATP-2, taking into account the prospects of both the Russian and world markets for future ATP, in close contact with leading Russian industry scientific centers(TsAGI, CIAM, VIAM, LII) In the 90s, the OKB continued to work on various aspects of the SPS-2 project. By the second half of the 90s, the appearance of the future Russian SPS-2 Tu-244 had more or less taken shape, although in the course of further development of the project, the first flight of the Tu-244 is possible with normal development of work no earlier than in five to ten years. Basic “tailless” aerodynamic configuration, power plant of four turbojet engines in separate engine nacelles, take-off weight 320-350 tons, cruising speed M=2.0-2.05. The selected take-off weight, dimensions and passenger capacity (250-300 or more passengers) make it possible to ensure competitiveness with subsonic aircraft (such as the Boeing 747 and A 310) with 300-500 seats. The layout of the Tu-244 is aimed at ensuring high aerodynamic quality both in supersonic cruising flight (up to 9 or more), and in subsonic flight modes (up to 15-16), as well as in takeoff and landing modes to reduce noise levels and create increased comfort for passengers. The wing is trapezoidal in plan with an overflow and has a complex deformation of the middle surface and a variable profile along the span. Pitch and roll control, as well as balancing, are provided by elevons; the leading edge is equipped with mechanization such as deflectable toes. Compared to the Tu-144, the base part of the wing has a significantly smaller sweep angle along the leading edge, while maintaining a large sweep of the float part, which provides a compromise between cruising flights at high speeds. supersonic speeds and at subsonic levels. The wing design is close to the Tu-144. It is envisaged to widely use composites in the structure of the wing, fuselage, tail, and engine nacelles, which should ensure a reduction in airframe weight by 25-30%. As on the Tu-144, the vertical tail has a two-section rudder and is structurally similar to the wing. The fuselage consists of a pressurized cabin, a nose and a tail compartment. For the selected passenger capacity of 250-320 people, a fuselage with a width of 3.9 m and a height of 4.1 m was optimal. The Tu-244 abandoned the deflectable nose of the fuselage. The glazing of the cockpit provides the necessary visibility in flight, and during takeoff and landing conditions the required visibility is provided by an optical-electronic vision system. The increase in the weight of the aircraft required a change in the landing gear layout, unlike the Tu-144, on the Tu-244 the landing gear consists of one front and three main struts, of which the outer ones have three-axle bogies and are retracted into the wing, and the middle strut has a bi-axial bogie and is retracted into the fuselage . The take-off thrust of each engine is determined to be 25,000 kgf, but the type is not yet completely clear: both DIC and conventional dual-circuit turbojet engines with an ejector nozzle, which provides noise absorption during takeoff and landing, are being considered. Systems and equipment of the Tu-244 should be developed taking into account the experience of the Tu-160 and Tu-204.
In an effort to ensure a flexible approach to the SPS-2 problem, during the work on the project, the OKB prepared several possible Tu-244 projects, differing in mass, dimensions, passenger capacity and minor differences in layout and design. In one of the latest versions of the Tu-244, proposed by the Design Bureau, we're talking about about an aircraft with a take-off weight of 300 tons, a wing area of 965 m 2, four turbofan engines with a take-off thrust of 25,500 kgf each and a passenger capacity of 254 people. The estimated practical range of supersonic flight with a normal commercial load is 7500 km.
Russia’s significant contribution to the development of SPS-2 was the creation of the Tu-144LL “Moscow” flying laboratory on the basis of the serial Tu-144D. Work on the Tu-144LL was carried out within the framework of international cooperation with the United States, with active funding from the Americans.
Information about the aircraft was presented at the Paris Air Show in June 1993. The estimated date of entry into service is 2025. The potential market is estimated at more than 100 aircraft.
Information sources:
- Under the signs “ANT” and “Tu” / V. Rigmant. Aviation and astronautics 9/2000 /
- Tu-244 OKB im. A.N.Tupoleva / Aircraft of Russia and CIS countries /
- "Civil Aviation"
In the very near future, Russia can again return supersonic passenger airliners to the skies, and an excellent help for this is the continuation of work on the final creation of the Tu-244 supersonic jet aircraft, developed back in Soviet times.
According to the most modest official statements, the Tu-244 aircraft will most likely be put into operation in 2025, that is, literally in 10 years. Of course, it is expected that its appearance will be somewhat different from the developments of Soviet aircraft manufacturers, but in general, the aircraft will remain as intended.
The Tu-244 supersonic jet aircraft will have 4 turbojet engines, allowing the aircraft to be lifted to an altitude of up to 20 thousand meters, which will significantly relieve the load on currently used routes. However, along with this there is a need for a long runway, but this task is quite feasible and relatively inexpensive, especially since a number of airports can already accept such aircraft.
The technical characteristics of the supersonic airliner are also very modern, although the work was carried out back in 1971. The estimated speed of the aircraft should reach 2175 km/h, but the possibility cannot be ruled out that it will be increased to 2500 km/h. The estimated number of passengers that can be accommodated on board the airliner is about 300 people, which, in principle, corresponds to modern trends in civil aviation. Supersonic jet aircraft Tu-244 will have enormous dimensions - its length will be about 88 meters, its wingspan will be 45 meters, and its height will be about 15 meters. However, at the moment, aircraft engineers are solving two very important problems that will truly make the aircraft truly modern:
- Increasing the flight range, since Soviet engineers considered that a flight of 9,200 kilometers would be optimal, but in reality, this is very little;
- Reducing the fuel consumption of the aircraft, since we recall that it was precisely for this reason that the whole world abandoned the use of jet airliners.
If the first problem is solved relatively easily, then the second one may have a number of difficulties. However, work on the implementation of this project is underway, and it is quite possible that in the very near future we will be able to see a supersonic passenger aircraft Tu-244 in the sky.
The advantages of using supersonic jet airliners are undeniable:
- Flights between regions, states and continents will become as fast and comfortable as possible, as passengers will be able to fly to their destination three or more times faster;
- Due to the large capacity of the aircraft, it will be possible to slightly reduce the cost of air travel;
- The ease of aircraft maintenance will increase, since one large aircraft will be serviced much faster than two small airliners.
Tu-244 history
Consideration of the project of the second generation supersonic aircraft SPS-2 began approximately in the period from 1971 to 1973. Engineers from the Design Bureau, citing the experience of creating the Soviet Tu-144 and the American SPS, prepared the announced project for the Tu-244.
Focused on specifications already existing and designed types of subsonic passenger aircraft. The calculations also included the aircraft's competitiveness in terms of cost-effectiveness, environmental friendliness and passenger amenities.
In the efficiency criterion, the emphasis fell on the greater performance of the SPS-2 in comparison with subsonic vehicles. That is, the number of aircraft of the Tu-244 type is much smaller, but the efficiency is higher. On the one hand, SPS-2 required a large amount of fuel, but, on the other hand, the air carrier would need half as many such aircraft as compared to conventional scheduled aircraft.
From an environmental point of view, SPS-2 was both beneficial and not. During the years of creation of the supersonic aircraft (60s - 70s), they did not pay much attention to environmental factors. But the same sonic booms, the release of harmful substances, noise in the area and the negative impact on the ozone layer had negative consequences for the creation of the aircraft.
The creation of SPS-2 took more than 25 years. During this time, OKB employees designed several versions of the Tu-244. They had differences in terms of aerodynamic layout, power plant, airframe and flight characteristics. If we compare SPS-2 and SPS-1, we can observe a huge difference in the level of aerodynamics, efficiency of power plants and overall weight and dimensions. Initially, all work on SPS-2 was carried out personally by A. Tupolev, but after some time the responsibilities were assigned to the designer A. Pukhov. M. Kazakov was engaged in technical management of the Tu-244 aircraft.
The first planned project for the Tu-244 was a variant produced in 1973. It was planned to install four engines with a total thrust of 37,500 kgf. Cruising supersonic mode – 1.23 kg/kgf per hour. Take-off weight - 360 tons, payload - 30 tons. Depending on the layout options, the aircraft could carry from 264 to 321 passengers. The total wing area is 1100 m2. When reaching cruising speed, the device could fly at a distance of up to 8000 km.
The base for the aircraft was the Tu-144. To increase the Kmax value of the aircraft, engineers reduced the relative midsections of the engine nacelles and fuselage, and attached a more elongated wing. Mechanization of the leading edge of the wing was used in the form of deflectable nose parts. Separate engine nacelles with axial air intakes were placed behind the maximum wing thickness mark.
At the end of 76, the military-industrial complex under the Council of Ministers of the USSR put forward a decision on SPS-2, which determined the procedure for creation and the main data on the Tu-244. According to this decision, the first SPS-2 should have small dimensions with a take-off weight of up to 275 tons. The wing area is 750 m 2, the take-off weight of the engines is up to 27,500 kgf. But the decision took into account the possibility of creating a larger device.
By 1985, OKB employees prepared a technical proposal for the Tu-244 with the presence of a DIC, giving take-off thrust up to 24,000 kgf. The use of variable cycle engines would allow the most favorable optimization of the process of operation of the power plant in different flight modes and would create the possibility of performing highly economical subsonic flight over areas with a high population density.
A draft version of the SPS-2 using liquid hydrogen engines was also considered.
In 1993, two Tu-144D units were converted into flying laboratories to carry out work on the second generation SPS project.
In the 80s and 90s, when creating such aircraft, the question arose about the necessity and rationality of their use in general. All leading countries (France, USA, Germany, Italy, Great Britain, USSR, Japan and Italy) began to coordinate on environmental and economic factors.
Full information about the future aircraft became available to everyone at the Paris Air Show in 1993. The planned date for the aircraft to enter service is 2025. It is planned to create approximately 100 passenger aircraft.
Design of the Tu-244 aircraft
The layout aircraft is designed to provide high aerodynamic efficiency, regardless of the flight mode.
The trapezoidal wing of the Tu-244 has a bevel with complex deformation of the middle surface and a variable profile along the span. Ailerons provide roll and pitch control and balancing. A motorized type of deflectable toe is attached to the leading edge. From a structural point of view, the wing has a middle section (passes through the fuselage), a front section and a console. The middle part and consoles use multi-spar and multi-rib power circuits, the front part is ribless. For the most loaded wheel, it was decided to use material made of high-strength titanium alloy VT-6Ch.
From a structural point of view, the vertical tail is similar to a wing, and a two-section rudder is responsible for direction.
The fuselage includes a pressurized cabin, nose and tail compartments. Depending on different layouts, the diameter of the fuselage may be different. Also, the diameter is directly proportional to the future number of passenger seats. For example, if there will be from 250 to 320 passengers, the optimal choice of diameter will be 3.9 m. In this case, the seats will be placed as follows: tourist and business class - 3 + 3, and first class - 2 + 2 The new height of 4.1 m solves the problem of installing a convenient trunk under the floor of the passenger compartment. Additionally, you can conveniently load containers. The fuselage section of the Tu-204 aircraft is similar. Accordingly, the Tu-244’s pressurized cabin will be made of aluminum alloys, and the tail and nose compartments will be made of composite materials.
It should be noted that the aircraft does not have a cockpit canopy or a tiltable nose, as on the basic Tu-144 model. In flight, the necessary visibility will be provided due to the glazing of the cockpit, and during ground movements (runways), landing and takeoff, the necessary visibility will be provided by providing an optical-electronic viewing system that operates in all weather conditions and regardless of the time of day.
The chassis includes the front strut and three main ones. In turn, the outer struts are three-axial and are retracted into the wing, and the central one has a biaxial bogie and is hidden in the fuselage. A similar nose gear strut is found on the Tu-144 aircraft. The use of three main supports in the design is carried out to ensure the impact of specified loads on the runway concrete. Navigation and flight equipment will provide landing according to ICAO category IIIA.
Tu-244 characteristics:
| Dimensions | ||
| Fuselage length, m | 88,7 | |
| Wingspan, m | 54,77 | |
| Wing area, m2 | 1200 | |
| Wing extension | 2,5 | |
| Wing sweep along the leading edge | center section | 75 o |
| consoles | 35 o | |
| Fuselage width, m | 3,9 | |
| Fuselage height, m | 4,1 | |
| Volume luggage compartment, m 3 | 32 | |
| Weight | ||
| Take-off (maximum), kg | 350000 | |
| Aircraft without fuel, kg | 172000 | |
| Fuel weight, kg | 178 000 | |
| Power point | ||
| Engines | 4 DTRD | |
| Thrust (forced), kG | 4х 33000 | |
| Flight data | ||
| Cruising speed, M | 2,05 | |
| Practical flight range, km | 9200 | |
| Flight altitude, m | 18000-20000 | |
| Tu-244 | ||
|---|---|---|
| Dimensions | ||
| Tu-244 | ||
| Fuselage length, m | 88,7 | |
| Wingspan, m | 54,77 | |
| Wing area, m2 | 1200 | |
| Wing extension | 2,5 | |
| Wing sweep along the leading edge | center section | 75^o |
| consoles | 35^o | |
| Fuselage width, m | 3,9 | |
| Fuselage height, m | 4,1 | |
| Luggage compartment volume, m3 | 32 | |
| Masses | ||
| Tu-244 | ||
| Take-off (maximum), kg | 350000 | |
| Aircraft without fuel, kg | 172000 | |
| Fuel weight, kg | 178 000 | |
| Power point | ||
| Tu-244 | ||
| Engines | 4 DTRD | |
| Thrust (forced), kG | 4х 33000 | |
| Flight data | ||
| Tu-244 | ||
| Cruising speed, M= | 2,05 | |
| Practical flight range, km | 9200 | |
| Flight altitude, m | 18000-20000 | |
Description
In 1988, the A.N. Tupolev Design Bureau began research on the second-generation supersonic passenger aircraft Tu-244 (SPS-2). Western experts estimate the need for 500-1200 such aircraft for the whole world in the first or second decade of the 21st century.
The competitiveness of such an aircraft (compared to a conventional subsonic passenger aircraft) must be ensured by economic efficiency, environmental acceptability and convenience for passengers. At the same time, economic efficiency (that is, lower unit costs) is determined by the high productivity of the SPS, which makes it possible to transport growing passenger traffic with a smaller number of supersonic aircraft in comparison with the required fleet of subsonic ones. The difference in the cost of the required number of passenger aircraft and the cost of operating them can compensate for increased fuel costs for airlines.
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The environmental acceptability of an ATP is also a critical factor in its success or failure. The solution to this problem is associated with determining the level of environmental impact of supersonic passenger plane on the environment (sonic boom, noise in the area, emission of harmful substances, including the impact on the ozone layer), which can be taken international organizations as certification standards will make the airliner economically rational. In its own way physical nature A supersonic aircraft has a greater impact on the environment than a subsonic aircraft of the same passenger capacity and flight range.
These circumstances forced leading aircraft manufacturing firms in the USA, England, France, Germany, Italy, Japan, and Russia to coordinate their research, primarily in the field of environmental impact, as well as in assessing humanity’s need for supersonic transport and determining rational parameters of the ATP. The well-known “Group of Eight” was created - Boeing, McDonnell Douglas, British Aerospace, Aerospatiale, Deutsche Aerospace Airbus, Alenia, the Association of Japanese Aviation Corporations, ASTC. A.N. Tupolev.
The entire period after the creation of the Tu-144 ANTK im. A.N. Tupolev. together with leading industry research centers (such as TsAGI, CIAM, VIAM, LII) did not stop working on the second generation ATP. These works consist of the general design of the aircraft, the development of its components, as well as research and experimental work to create new materials, coatings, and technological processes. The experience of creating the Tu-144 was widely used in the development of the new aircraft, and in 1993, two Tu-144 were converted into flying laboratories as part of the work on the second generation ATP.
Here are some characteristic features of the Tu-244:
- basic “tailless” aerodynamic design, characterized by the absence horizontal tail;
- a propulsion system consisting of four turbojet engines, placed one at a time in separate engine nacelles;
- take-off weight up to 320-350 tons, which is significantly more than that of the Tu-144 and Concorde;
- cruising speed corresponding to Mach number = 2-2.05.
Design
The large size of the aircraft is determined by the increased passenger capacity (250-300 seats or more) compared to 110-150 for the Tu-144 and Concorde, which is necessary for successful competition with subsonic aircraft (such as the Boeing 747, A-310 ), with 300-500 seats.
The layout of the Tu-244 aircraft is aimed at ensuring high aerodynamic quality both at supersonic cruising and at takeoff and landing modes to reduce noise levels, as well as creating increased comfort for passengers.
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WING The Tu-244 has a trapezoidal shape in plan with an influx, has a complex deformation of the middle surface and a variable profile along the span. Pitch and roll control, as well as balancing, are provided by ailerons. The leading edge is equipped with mechanization such as deflectable toes. If on the Tu-144 aerodynamic quality of 8.1 was actually achieved at M = 2, then on the Tu-244 it was planned to achieve a lift quality of 10 at M = 2 and 15 at M = 0.9.
Structurally, the wing is divided into a middle wing, passing through the fuselage, consoles and the front part. A multi-spar and multi-rib power design was adopted for the middle part and consoles and a ribless one for the front part of the wing, as on the Tu-144.
It is advisable to use a high-strength titanium alloy of the VT-6Ch type as a structural material for the most loaded caisson of the middle part of the wing and consoles. For the relatively lightly loaded front part of the wing, for mechanization and non-power elements, aluminum alloys and composite materials are being studied. The widespread use of composite materials, for example graphite-epoxy, in the structure of the wing, tail, engine nacelles, fuselage, according to our and foreign experts, can ensure a reduction in airframe weight by 25-30% by the year 2000.
The wing contains fuel caisson tanks and niches for cleaning the main landing gear.
VERTICAL TERMINATION It has a two-section rudder and is structurally similar to a wing.
FUSELAGE consists of a pressurized cabin, bow and tail compartments. The choice of the optimal fuselage diameter depends on passenger capacity. For the number of passengers 250-320, the optimal fuselage is 3.9 meters wide, in which passenger seats are arranged in a 3+3 abreast pattern in tourist and business classes and 2+2 in first class. The height of 4.1 meters allows you to equip a convenient trunk under the floor passenger compartment with loading of international containers. The Tu-204 aircraft has a similar fuselage section. The pressurized cabin will be made of aluminum alloys, the bow and tail compartments will be made of composites.
The plane does not have a deflectable nose, like the Tu-144. There is no ordinary cockpit “canopy” either. The glazing of the cockpit provides the necessary visibility during flight, and during takeoff, landing and movement on the ground, the required visibility of the runway is provided by an optical-electronic vision system that operates in all weather conditions.
CHASSIS consists of a front strut and three main ones, of which the outer ones have three-axle bogies and are retracted into the wing, and the middle strut has a two-axle bogie and is retracted into the fuselage. The prototype of the nose support is the strut of the Tu-144 aircraft. The scheme with three main supports was chosen based on the conditions for ensuring the specified loads on the concrete of the runway.
Flight and navigation equipment had to provide landing in accordance with ICAO category IIIA.
State
Information about the aircraft was presented at the Paris Air Show in June 1993. Estimated delivery date. into operation - 2025. The potential market is estimated at more than 100 aircraft.
Due to the lack of funding, the work remained at the research stage, and the Tu-144LL flying laboratory since 1997, according to the Russian-American agreement, has been used under the program for creating next-generation supersonic passenger aircraft HSR.
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