The successes in the creation of supersonic combat aircraft, including the heavy class, in the 50s created a favorable environment for studying the possibility of creating a supersonic passenger aircraft (SPS). The history of the appearance of the first SPS projects goes back to the early post-war years, when several hypothetical projects were proposed in the USA and Great Britain, which were very far from practical implementation in terms of their technical solutions. In the second half of the 50s, on both sides of the Iron Curtain, first experienced and then serial supersonic heavy military aircraft appeared, and, almost immediately, on their basis, the world's leading aviation companies were preparing projects for ATP of various aerodynamic and layout schemes. A detailed analysis and further study of the proposed ATP projects based on the first supersonic bombers showed that the creation of an effective competitive ATP by modifying a military prototype is an extremely difficult task (in contrast to the process of creating the first jet passenger aircraft based on subsonic heavy combat aircraft).
The first supersonic combat heavy aircraft, in terms of their design solutions, basically met the requirements of a relatively short-term supersonic flight. For the ATP, it was required to ensure a long cruising flight at speeds corresponding to at least M = 2, plus the specifics of the task of transporting passengers required a significant increase in the reliability of the operation of all elements of the aircraft structure, subject to more intensive operation, taking into account the increase in the duration of flights at supersonic modes. Gradually, analyzing all possible options for technical solutions, aviation specialists, both in the USSR and in the West, came to the firm opinion that an economically effective ATP should be designed as a fundamentally new type of aircraft.
Andrei Nikolaevich decided to entrust the design of the Tu-144 to the "K" Division, which had previously been engaged in unmanned vehicles and had sufficient experience in mastering long-term flight at speeds exceeding M = 2 (the Tu-121 attack unmanned aircraft, unmanned reconnaissance aircraft - serial Tu-123 and experienced Tu-139). Andrey Nikolaevich appointed A.A. Tupolev as the chief designer and head of work on the Tu-144. It was under his leadership, with the involvement of the best forces of domestic aviation science and technology, that the ideology and future appearance of the Tu-144 were born in the "K" department. Later, after the death of A.N. Tupolev and the appointment of A.A. Tupolev as the head of the enterprise, the topic of Tu-144 was directed by Yu.N. Popov and B.A. Gantsevsky. Soon, the Tu-144 becomes one of the main and priority topics in the activities of the Design Bureau and the entire MAP for the next 10 years.
The aerodynamic appearance of the Tu-144 was determined mainly by obtaining a long flight range in a cruising supersonic mode, subject to obtaining the required stability and controllability characteristics and given take-off and landing characteristics. Based on the promised unit costs of the NK-144, at the initial design stage, we set the task of obtaining Kmax = 7 at the cruising supersonic flight mode. For total economic, technological, weight considerations, the number M of cruising flight was taken to be 2.2. During the development of the aerodynamic layout of the Tu-144 in the OKB and TsAGI, several dozen possible options were considered. We studied the "normal" layout with a horizontal tail section of the fuselage, it was abandoned, since such a tail gave up to 20% in the overall balance of the aircraft resistance. They also abandoned the "canard" scheme, assessing the problem of the effect of the destabilizer on the main wing. Finally, proceeding from the conditions for obtaining the required aerodynamic quality and obtaining minimum focus spreads at subsonic and supersonic speeds, we settled on the low-wing scheme - "tailless" with a compound delta wing of an ogival shape (the wing was formed by two triangular surfaces with a sweep angle along the leading edge of 78 ° - for the front inflow parts and 55 ° - for the rear base part), with four DTRDF, placed under the wing, with vertical tail, located along the longitudinal axis of the aircraft, and a tricycle retractable landing gear.
Traditional aluminum alloys were mainly used in the airframe design. The wing was formed from symmetrical profiles and had a complex twist in two directions: longitudinal and transverse. This achieved the best flow around the wing surface in the supersonic mode, in addition, such a twist helped to improve the longitudinal balancing in this mode. Elevons were located along the entire trailing edge of the wing, which consisted of four sections on each wing. The wing structure is multi-spar, with a powerful working skin made of solid plates made of aluminum alloys, central part wings and elevons were made of titanium alloys. Elevon sections were powered by two irreversible boosters. The rudder was also deflected with the help of irreversible boosters and consisted of two, independent of each other, sections. The aerodynamic shape of the fuselage was selected from the conditions for obtaining the minimum drag in the supersonic regime. In order to achieve this, we even made some complications in the design of the aircraft.
A characteristic feature of the Tu-144 was the descending, well-glazed nose of the fuselage in front of the pilot's cockpit, which provided good overview at high takeoff and landing angles of attack typical of an aircraft with a low aspect ratio wing. Lowering and raising the nose of the fuselage was carried out using a hydraulic drive. When designing the deviating non-hermetic part and its units, it was possible to maintain the smoothness of the skin at the junction of the moving part with the pressurized cabin and the rest of the fuselage surface. The shape of the nacelles was mainly determined by layout considerations and the conditions for the reliability of the power plant. Four DTRDF NK-144 were placed under the wing close to each other. Each engine had its own air intake, and two adjacent air intakes were combined into a common block. The underwing air intakes are flat with a horizontal wedge. The deceleration of the flow at supersonic flight speeds was carried out in three oblique shock waves, in a direct closing shock, and in a subsonic diffuser. The operation of each air intake was provided by an automatic control system, which changed the position of the wedge panels and bypass flaps depending on the operating mode of the NK-144 engine. The length of the nacelles was determined by the size of the engines and the requirements of TsAGI and TsIAM to ensure the required length of the air intake ducts for the normal operation of the engines. It should be noted that, in contrast to the design of the air intakes and engines of the Concorde, where this process proceeded as a whole, the design of the NK-144 and nacelles with air intakes proceeded as two largely independent processes, which led to some extent to the oversize of nacelles and in the future, to many mutual discrepancies in the operation of engines and the air intake system.
It was supposed, as on the "Concorde", to introduce a braking system on landing due to the reverse of the engines, the reverse was planned to be installed on the two extreme engines (the reverse system was not brought up, as a result of which the experimental and production vehicles were operated with a brake parachute). The main landing gear was retracted into the wing, the front landing gear was retracted into the front of the fuselage in the space between the two air intakes. The low construction height of the wing required a reduction in the size of the wheels, as a result of which a twelve-wheeled bogie with wheels of a relatively small diameter was used in the main landing gears. The main fuel supply was located in the wing caisson tanks. The front wing box-tanks and an additional keel tank served to balance the aircraft. The main work on the selection of the optimal aerodynamic scheme of the Tu-144 in the OKB was headed by G.A. Cheremukhin, the division headed by V.M. Bul was engaged in the optimization of the power plant for the project. In particular, the steering assemblies of the aircraft control drive worked out the signals of the system for improving stability and controllability along the longitudinal and track channels. In some modes, this measure allowed for a flight with static instability.
The choice of the ideology of the Tu-144 control system is largely the merit of G.F. Naboishchikov. In creating and communicating this fundamentally new system management made a great contribution L.M. Rodnyanskiy, who was previously engaged in control systems in the design bureau of P.O. Sukhoi and V.M. Myasishchev, and in the early 60s did a lot to fine-tune the very "raw" control system of the Tu-22. The cockpit was designed taking into account the requirements of modern ergonomics, it was carried out with four seats: the first and second pilots occupied the two front seats, behind them was the flight engineer, the fourth place on the first prototype was intended for the experimental engineer. In the future, it was supposed to limit the crew to three pilots. The decoration and layout of the Tu-144 passenger compartment met world requirements for modern design and to the comfort, the latest finishing materials were used in their finishing. The Tu-144 flight and navigation equipment was equipped with the most advanced systems that domestic avionics could provide at that time: a perfect autopilot and an on-board electronic computer automatically kept the course; pilots could see on a screen located on dashboard, where in this moment the plane is located and how many kilometers are left to the destination; the landing approach was carried out automatically at any time of the day in difficult weather conditions, etc. - all this was a serious leap forward for our aviation.
The construction of the first prototype Tu-144 ("044") aircraft began in 1965, while the second prototype was being built for static tests. Experienced "044" was originally designed for 98 passengers, later this figure was increased to 120. Accordingly, the estimated take-off weight increased from 130 tons to 150 tons. The prototype was built in Moscow in the shops of the MMZ "Opyt", some of the units were manufactured at its branches. In 1967, the assembly of the main elements of the aircraft was completed. At the end of 1967, the experienced "044" was transported to ZHLI and DB, where, throughout 1968, finishing work and completing the machine with the missing systems and assemblies were carried out.
At the same time, flights of the MiG-21I analogue aircraft (A-144, "21-11"), created on the basis of the MiG-21S fighter, began at the LII airfield. An analogue was created in the design bureau of A. I. Mikoyan and had a wing geometrically and aerodynamically similar to the wing of the experimental "044". In total, two 21-11 aircraft were built, many test pilots flew on them, including those who were to test the Tu-144, in particular E.V. Elyan. The analog aircraft successfully flew up to a speed of 2500 km / h and the materials of these flights served as the basis for the final adjustment of the Tu-144 wing, and also allowed the test pilots to prepare for the peculiarities of the behavior of an aircraft with such a wing.
At the end of 1968, the experienced "044" (board number 68001) was ready for the first flight. A crew was assigned to the car, consisting of: the commander of the ship - honored test pilot E.V. Ye-lyan (who then received a Hero Soviet Union); co-pilot - Honored Test Pilot Hero of the Soviet Union M.V. Kozlov; lead test engineer V.N. Benderov and flight engineer Yu.T. Seliverstov. Taking into account the novelty and uncommonness of the new car, the Design Bureau took an extraordinary decision: for the first time it was decided to install ejection crew seats on an experimental passenger car. During the month, engine races, runs, and last ground system checks were held. From the beginning of the third decade of December 1968, "044" was in prelaunch readiness, the car and the crew were completely ready for the first flight, during all these ten days there was no weather over the LII airfield and the experienced Tu-144 remained on the ground. Finally, on the last day of the outgoing 1968, 25 seconds after the start, "044" for the first time broke away from runway airfield LII and quickly gained altitude. The first flight lasted 37 minutes, during the flight the car was accompanied by an analogue plane "21-11".
A supersonic passenger aircraft and it was an aircraft built in the USSR, the first "Concorde" will go into flight only on March 2, 1969. It has been proven in practice that heavy tailless aircraft have the rights of citizenship in the USSR (before this flight, everything was limited to a large number of heavy tailless aircraft). On June 5, 1969, the prototype aircraft for the first time at an altitude of 11,000 m exceeded supersonic speed, by May 1970 the car was flying at speeds of M = 1.25-1.6 at altitudes up to 15,000 m. On November 12, 1970, in an hour-long flight "044" flew for half an hour at a speed exceeding 2000 km / h, at an altitude of 16960 m, the maximum speed of 2430 km / h was reached. During the tests, the prototype flew several times abroad, in May-June 1971 "044" took part in the salon at Le Bourget , where she first "met" with the Anglo-French "Concorde". The "044" was equipped with experimental NK-144 engines with a specific fuel consumption in the cruising supersonic mode of 2.23 kg / kgf hour, with such specific costs on tests the Tu-144 managed to reach a supersonic flight range of 2920 km, which was significantly less than the required range ... In addition, during the tests, we encountered some design flaws: in flights, increased vibration and heating of the tail section of the fuselage from the quad engine package were observed, even titanium structures did not help out. After completing the program of test flights "044" (a total of about 150 flights), and remained in one prototype. It was not required more from her, she fulfilled her task of proving the technical feasibility of creating a supersonic passenger aircraft in the USSR. It was necessary to move further, improving the design of the aircraft and engines.
Work on the development of the basic design of the aircraft "044" went in two directions: the creation of a new economical turbojet engine of the RD-36-51 type and a significant improvement in the aerodynamics and design of the Tu-144. The result was to meet the requirements for the range of supersonic flight. The decision of the Commission of the Council of Ministers of the USSR on the version of the Tu-144 with the RD-36-51 was adopted in 1969. At the same time, at the suggestion of MAP-MGA, a decision is made, until the creation of RD-36-51 and their installation on Tu-144, on the construction of six Tu-144 with NK-144A with reduced specific fuel consumption. The design of the serial Tu-144 with NK-144A was supposed to be significantly modernized, to make significant changes in the aerodynamics of the aircraft, having received more than 8 Kmax at the supersonic cruising mode. This modernization was supposed to meet the requirements of the first stage in terms of range (4000-4500 km) transition in series to RD-36-51.
Construction of the pre-production modernized Tu-144 ("004) aircraft began at the MMZ" Experience "in 1968. According to the calculated data with the NK-144 engines (Cp = 2.01), the estimated supersonic range should have been 3275 km, and with the NK-144A (Cp = 1.91), exceed 3500 km. In order to improve the aerodynamic characteristics of the aircraft in cruise mode M = 2.2, the wing shape was changed in plan (the sweep of the flowing part along the leading edge was reduced to 76 degrees, and the baseline was increased to 57 degrees), the wing shape became closer to the "Gothic" one. Compared with the "044", the wing area has increased, a more intensive conical twist of the wing end parts has been introduced. However, the most important innovation in wing aerodynamics was the change in the middle part of the wing, which ensured self-balancing in cruise mode with minimal loss of quality, taking into account the optimization of flight deformations of the wing in this mode. The length of the fuselage was increased to accommodate 150 passengers, the shape of the nose was improved, which also positively influenced the aerodynamics of the aircraft.
Unlike "044", each pair of engines in paired engine nacelles with air intakes was pushed apart, freeing the lower part of the fuselage from them, relieving it from increased temperature and vibration loads, while changing the lower wing surface in the place of the calculated area of flow compression, increasing the gap between the lower surface of the wing and the upper surface of the air intake - all this made it possible to use more intensively the effect of pressing the flow at the inlet to the air intakes on the Kmax than it was possible to get on the "044". The new layout of the engine nacelles required changes in the chassis: the main landing gear struts were placed under the engine nacelles, with their retraction inside between the air channels of the engines, they switched to an eight-wheeled bogie, and the nose landing gear retraction scheme was also changed. An important difference between "004" and "044" was the introduction of a front multi-section retractable wing-ka-destabilizer, which was extended from the fuselage in take-off and landing modes, and made it possible to provide the required balancing of the aircraft with deflected flaps elevons. Modifications to the design, an increase in payload and fuel reserves led to an increase in the airplane's take-off weight, which exceeded 190 tons (for "044" - 150 tons).
The construction of the pre-production Tu-144 No. 01-1 (side No. 77101) was completed at the beginning of 1971; on June 1, 1971, the aircraft made its first flight. Under the factory test program, the aircraft completed 231 flights, lasting 338 hours, of which 55 hours the plane flew supersonic. On this machine, complex issues of interaction between the power plant and the aircraft in various flight modes were worked out. On September 20, 1972, the car flew along the Moscow-Tashkent highway, while the route was completed in 1 hour 50 minutes, the cruising speed during the flight reached 2500 km / h. The pre-production vehicle became the basis for the deployment of serial production at the Voronezh Aviation Plant (VAZ), which was ordered by the government to master the Tu-144 in the series.
The first flight of serial Tu-144 No. 01-2 (side No. 77102) powered by NK-144A engines took place on March 20, 1972. In the series, according to the results of tests of the pre-production machine, the aerodynamics of the wing was corrected and its area was slightly increased again. The takeoff weight in the series reached 195 tons. The specific fuel consumption of the NK-144A by the time of operational tests of serial machines was intended to be increased to 1.65-1.67 kg / kgf h by optimizing the engine nozzle, and later to 1.57 kg / kgf h, while the flight range should was to increase to 3855-4250 km and 4550 km, respectively. In fact, they were able to achieve by 1977, during tests and refinements of the Tu-144 and NK-144A series, Cp = 1.81 kg / kgf hour at cruising supersonic thrust mode 5000 kgf, Cp = 1.65 kg / kgf hour at takeoff afterburner thrust mode 20,000 kgf, Cp = 0.92 kg / kgf hour at a subsonic cruising mode of thrust of 3000 kgf and at maximum afterburner mode in a transonic mode, they received 11800 kgf.
On June 3, 1973, the first production car crashed during a demonstration flight at Le Bourget. The crew, headed by test pilot M.V. Kozlov, died (in addition to M.V. Kozlov, the second pilot V.M. Molchanov, Deputy Chief Designer V.N. Benderov, flight engineer A.I. Dralin, navigator G. N. Bazhenov, engineer B.A. Pervukhin). To investigate the disaster, a commission was created, in which experts from the USSR and France took part. According to the results of the investigation, the French noted that there was no refusal in the technical part of the aircraft, and the cause of the disaster was: the presence of unfastened crew members in the cockpit, the sudden appearance of the Mirage aircraft in the field of view of the Tu-144 aircraft crew, the presence of a movie camera in the hands of one of the crew members , which, if dropped, could jam the steering wheel. Apparently, at that moment, such a conclusion suited everyone. Perhaps the most succinct and precise about the Tu-144 disaster in Le Bourget in the 90s was expressed by E.V. Elyan: French flight control services led to tragic consequences. "
The production of the Tu-144 with the NK-144A continued in Voronezh until the beginning of 1977. A large volume of flight tests was carried out on these machines and flights with passengers began. On Tu-144 # 02-1 (board # 77103), the first flight was performed on December 13, 1973, the NPK-144 flight and navigation complex, the power supply system were tested, tests were carried out in interrupted take-off modes, technical flights were made in the cities of the USSR.
Tu-144 # 02-2 (tail # 77144), first flew on June 14, 1974, conducted research on aerodynamics, strength, behavior at high angles of attack, checked the operation of aircraft systems and equipment in abnormal flight situations, in 1975 the car flew at Le Bourget.
Tu-144 No. 03-1 (side No. 77105) was built in 1973 and immediately converted into Tu-144D with RD-36-51A engines.
Tu-144 No. 04-1 (side No. 77106), first flight on March 4, 1975, was used to assess the efficiency of the SCR, it solved some problems with the fuel system. On December 26, 1975, this aircraft was used for the first operational flight on the route Moscow - Alma-Ata. By this time, in addition to MAP pilots, MGA pilots had already started flying on the Tu-144. The plane transported cargo, mail along the route, flights took place at altitudes of 18,000 m and at speeds of 2,200 km / h. Currently, Tu-144 № 04-1 can be seen in the exposition of the Museum in Monino.
Tu-144 No. 04-2 (side No. 77108), first flight on December 12, 1975, finishing work was carried out on the systems of navigation equipment, on the ABSu-144, on the director approach system, on the autothrottle.
Tu-144 No. 05-1 (side No. 77107), first flight on August 20, 1975, after factory tests and tests under various programs, was presented in 1977 as a complex object for joint state tests. According to the results of these tests, it was noted that the flight performance of the aircraft, with the exception of the practical flight range with a given number of passengers, takeoff weight, correspond to the requirements set for the Tu-144 (during the tests, we obtained a practical flight range at supersonic with a takeoff weight of 195 tons at a payload 15 tons 3080 km, with 7 tons - 3600 km. It was emphasized that the flight range of 4000-4500 km, with a payload of 14-15 tons on the Tu-144 with the NK-144A cannot be realized and it was noted that obtaining the required range is possible with engines RD-36-51A.
After the end of the joint tests, the MAP-MGA decided to start passenger traffic on Tu-144 aircraft with NK-144A. Tu-144 No. 05-2 (board number 77109), first flight on April 29, 1976, and Tu-144 No. 06-1 (board number 77110), first flight on February 14, 1977, were used for regular passenger traffic on the Moscow - Alma-Ata. The Tu-144 departed for its first passenger flight on November 1, 1977. Flights over a distance of 3260 km at an altitude of 16000-17000 m at a speed of 2000 km / h were carried out once a week, the number of passengers on board did not exceed 80 people. Until the termination of regular operation with passengers in May 1978, the crews of Aeroflot on the Tu-144 performed 55 flights, carrying 3284 passengers. The Tu-144 with the NK-144A became the first passenger aircraft in the USSR to receive a national airworthiness certificate for the safety of passenger transportation, the rest of Aeroflot's aircraft at that time did not have such a certificate (the exception was Tu-134, which was certified in Poland according to English standards airworthiness).
Modification: Tu-144
Wingspan, m: 28.80
Aircraft length, m: 65.70
Aircraft height, m: 12.85
Wing area, m2: 507.00
Weight, kg
- empty aircraft: 91800
-normal takeoff: 150,000
-maximum takeoff: 195000
Engine type: 4 х ТРДДФ НК-144А
Thrust, kgf
-normal: 4 x 15000
-Forced: 4 x 20,000
Maximum speed, km / h: 2500 (M = 2.35)
Cruising speed, km / h: 2200
Practical range, km: 6500
Flight range at supersonic, km: 2920
Practical ceiling, m: 18000-20000
Crew, people: 3
Payload of 150 passengers or 15,000 kg of cargo.
Tu-144 before the first flight.
Tu-144 after takeoff.
Exactly 15 years ago, British Airways' last three supersonic Concorde airliners made their farewell flight. On that day, October 24, 2003, these aircraft, flying at low altitude over London, landed at Heathrow and thus completed the short history of supersonic passenger aviation. Nevertheless, today aircraft designers around the world are again thinking about the possibility of fast flights - from Paris to New York in 3.5 hours, from Sydney to Los Angeles in 6 hours, from London to Tokyo in 5 hours. But before supersonic aircraft return to international passenger routes, developers will have to solve many problems, among which one of the most important is to reduce the noise of fast aircraft.
A short history of fast flying
Passenger aviation began to take shape in the 1910s, when the first aircraft specifically designed to carry people by air appeared. The very first of these was the French Bleriot XXIV Limousine by Bleriot Aeronautique. It was used for entertainment air walks... Two years later, the S-21 "Grand" appeared in Russia, created on the basis of the heavy bomber "Russian Knight" by Igor Sikorsky. It was built at the Russian-Baltic Carriage Works. Then aviation began to develop by leaps and bounds: first, flights began between cities, then between countries, and then between continents. Airplanes made it possible to reach their destination faster than by train or ship.
In the 1950s, progress in the development of jet engines accelerated significantly, and supersonic flights became available for military aviation, albeit for a short time. Supersonic speed is usually called motion up to five times faster than the speed of sound, which changes depending on the propagation medium and its temperature. Under normal atmospheric pressure at sea level, sound travels at 331 meters per second, or 1191 kilometers per hour. As you climb, the density and temperature of the air decreases, and the speed of sound also decreases. For example, at an altitude of 20 thousand meters, it is already about 295 meters per second. But already at an altitude of about 25 thousand meters and as it rises to more than 50 thousand meters, the temperature of the atmosphere begins to increase slightly in comparison with the lower layers, and with it the local speed of sound also increases.
The rise in temperature at these altitudes is explained, among other things, by the high concentration of ozone in the air, which forms an ozone shield and absorbs part of the solar energy. As a result, the speed of sound at an altitude of 30 thousand meters above the sea is about 318 meters per second, and at an altitude of 50 thousand - almost 330 meters per second. In aviation, the Mach number is widely used to measure flight speed. In simple terms, it expresses the local speed of sound for a specific altitude, density and air temperature. So, the speed of a conditional flight, equal to two Mach numbers, at sea level will be 2383 kilometers per hour, and at an altitude of 10 thousand meters - 2157 kilometers per hour. For the first time, the sound barrier at a speed of 1.04 Mach number (1066 kilometers per hour) at an altitude of 12.2 thousand meters was overcome by the American pilot Chuck Yeager in 1947. This was an important step towards the development of supersonic flight.
In the 1950s, aircraft designers in several countries around the world began working on projects for supersonic passenger aircraft. As a result, the French Concorde and the Soviet Tu-144 appeared in the 1970s. These were the first and still the only supersonic passenger aircraft in the world. Both types of aircraft used conventional turbojet engines optimized for long-term supersonic flight. Tu-144s were operated until 1977. The planes flew at a speed of 2.3 thousand kilometers per hour and could carry up to 140 passengers. However, tickets for their flights cost an average of 2.5-3 times more expensive than usual. Low demand for fast, but expensive flights, as well as general difficulties in the operation and maintenance of the Tu-144 led to the fact that they were simply removed from passenger flights. However, the aircraft were used for some time in test flights, including under a contract with NASA.
Concorde lasted much longer - until 2003. Flights on French liners were also expensive and were not very popular, but France and Great Britain continued to operate them. The cost of one ticket for such a flight was, in terms of today's prices, about 20 thousand dollars. The French Concorde flew at a speed of just over two thousand kilometers per hour. The plane could cover the distance from Paris to New York in 3.5 hours. Depending on the configuration, the Concorde could carry from 92 to 120 people.
The story of the Concordes ended abruptly and quickly. In 2000, the Concorde plane crash occurred, killing 113 people. A year later, a crisis began in passenger air transportation caused by the terrorist attacks of September 11, 2001 (two aircraft hijacked by terrorists with passengers crashed into the towers of the World shopping center in New York, another, the third - in the Pentagon building in Arlington County, and the fourth fell in a field near Shanksville in Pennsylvania). Then the warranty period for Concorde aircraft, which Airbus was engaged in, expired. All these factors together made the operation of supersonic passenger aircraft extremely unprofitable, and in the summer and fall of 2003, Air France and British Airways took turns to write off all Concordes.
After the closure of the Concorde program in 2003, there was still hope for the return of supersonic passenger aircraft to service. Designers hoped for new fuel-efficient engines, aerodynamic calculations and computer-aided design systems that could make supersonic flights economically affordable. But in 2006 and 2008 International organization civil aviation adopted new aircraft noise standards banning, inter alia, any supersonic flight over populated land areas in Peaceful time... This prohibition does not apply to specially allocated for military aviation air corridors. Work on projects for new supersonic aircraft has stalled, but today they have begun to gain momentum again.
Quiet supersonic
Today, several enterprises and government organizations around the world are engaged in the development of supersonic passenger aircraft. Such projects, in particular, are carried out Russian companies Sukhoi and Tupolev, the Zhukovsky Central Aerohydrodynamic Institute, the French Dassault, the Japanese Aerospace Research Agency, the European concern Airbus, the American Lockheed Martin and Boeing, as well as several startups, including Aerion and Boom Technologies. In general, the designers were conditionally divided into two camps. Representatives of the first of them believe that it will not be possible in the near future to develop a "quiet" supersonic aircraft corresponding to the noise level of subsonic airliners, which means that it is necessary to build a fast passenger aircraft that will switch to supersonic where it is allowed. This approach, the designers from the first camp believe, will still reduce the flight time from one point to another.
The designers from the second camp mainly focused on combating shock waves. In flight at supersonic speed, the airplane's glider generates many shock waves, the most significant of which arise in the nose and in the tail area. In addition, shock waves usually appear on the leading and trailing edges of the wing, on the leading edges of the empennage, in the areas of flow swirlers and on the edges of the air intakes. A shock wave is an area in which the pressure, density and temperature of the medium experience a sharp and strong jump. Observers on the ground perceive such waves as a loud bang or even an explosion - it is because of this that supersonic flights over the populated part of the land are prohibited.
The effect of an explosion or a very loud pop is produced by the so-called N-type shock waves generated by a bomb or supersonic fighter glider. On the graph of pressure and density growth, such waves resemble the letter N of the Latin alphabet due to a sharp increase in pressure at the wave front with a sharp drop in pressure after it and subsequent normalization. In laboratory experiments, researchers at the Japan Aerospace Exploration Agency found that changing the shape of the airframe can smooth out peaks in the shock wave graph, turning it into an S-type wave. Such a wave has a smooth and not so significant pressure drop as in the N-wave. NASA experts believe that S-waves will be perceived by observers as a distant slam of a car door.
N-wave (red) before aerodynamic optimization of a supersonic glider and similarity of S-wave after optimization
In 2015, Japanese designers assembled the D-SEND 2 unmanned glider, whose aerodynamic shape was designed in such a way as to reduce the number of shock waves arising on it and their intensity. In July 2015, the developers tested the glider at the Esrange missile range in Sweden and noted a significant decrease in the amount of shock waves generated on the surface of the new glider. During the test, the D-SEND 2, which was not equipped with engines, was dropped from hot air balloon from a height of 30.5 thousand meters. During the fall, the 7.9 meter glider gained speed at Mach 1.39 and flew past tethered balloons equipped with microphones at different heights. At the same time, the researchers measured not only the intensity and number of shock waves, but also analyzed the influence of the state of the atmosphere on their early occurrence.
According to the Japanese agency, the sonic boom from aircraft comparable in size to the Concorde supersonic passenger aircraft and made according to the D-SEND 2 scheme, when flying at supersonic speed, will be half as intense as before. The Japanese D-SEND 2 differs from the gliders of conventional modern aircraft by its non-axisymmetric nose. The keel of the apparatus is displaced to the bow, and the horizontal tail assembly is made all-turning and has a negative mounting angle with respect to the longitudinal axis of the airframe, that is, the tail ends are below the attachment point, and not above, as usual. The wing of the glider has a normal sweep, but is made stepped: it smoothly mates with the fuselage, and part of its leading edge is located to the fuselage at an acute angle, but closer to the trailing edge this angle increases sharply.
A similar scheme is currently being created by the American supersonic startup Aerion and developed by Lockheed Martin commissioned by NASA. With an emphasis on reducing the number and intensity of shock waves, the Russian (Supersonic Business Aircraft / Supersonic Passenger Aircraft) is also being designed. Some of the fast passenger aircraft projects are slated for completion in the first half of the 2020s, but aviation regulations have yet to be revised by then. This means that the new aircraft will initially perform supersonic flights only over water. The fact is that to remove the restriction on supersonic flights over populated land, developers will have to conduct many tests and submit their results to the aviation authorities, including the US Federal Aviation Administration and the European Aviation Safety Agency.
S-512 / Spike Aerospace
New engines
Engines are another serious obstacle to the creation of a serial passenger supersonic aircraft. Designers have already found many ways to make turbojet engines more economical than they were ten to twenty years ago. This is the use of gearboxes that remove the rigid coupling of the fan and the turbine in the engine, and the use of ceramic composite materials, which allow optimizing the temperature balance in the hot zone of the power plant, and even the introduction of an additional - third - air circuit in addition to the already existing two, internal and external. In the field of creating economical subsonic engines, designers have already achieved amazing results, and ongoing new developments promise significant savings at all. You can read more about promising research in our resource.
But, despite all these developments, it is still difficult to call supersonic flight economical. For example, the promising supersonic passenger aircraft of the Boom Technologies startup will receive three turbofan engines of the JT8D family from Pratt & Whitney or J79 from GE Aviation. In cruise flight, the specific fuel consumption of these engines is about 740 grams per kilogram-force per hour. In this case, the J79 engine can be equipped with an afterburner, which increases fuel consumption to two kilograms per kilogram-force per hour. This consumption is comparable to the fuel consumption of engines, for example, of the Su-27 fighter, whose tasks differ significantly from the transportation of passengers.
For comparison, the specific fuel consumption of the world's only serial turbofan engines D-27 installed on the Ukrainian An-70 transport aircraft is only 140 grams per kilogram-force per hour. The American CFM56 engine, a "classic" of Boeing and Airbus airliners, has a specific fuel consumption of 545 grams per kilogram-force per hour. This means that without serious redesign of the design of jet aircraft engines, supersonic flights will not become cheap enough to become widespread, and will be in demand only in business aviation - high fuel consumption leads to higher ticket prices. It will also not work to reduce the high cost of supersonic air transportation in volumes - the aircraft being designed today are designed to carry from 8 to 45 passengers. Ordinary planes can accommodate more than a hundred people.
However, in early October of this year, GE Aviation project a new Affinity turbofan jet engine. These power plants are planned to be mounted on the promising supersonic passenger aircraft AS2 by Aerion. The new power plant constructively combines the features of jet engines with a low bypass ratio for combat aircraft and power plants with a high bypass ratio for passenger aircraft. At the same time, there are no new and breakthrough technologies in Affinity. The new engine is classified by GE Aviation as a medium-bypass power plant.
The engine is based on a modified CFM56 turbofan gas generator, which, in turn, is structurally based on the gas generator from the F101, the power plant for the B-1B Lancer supersonic bombers. The power plant will receive an upgraded electronic digital engine management system with full responsibility. The developers did not disclose any details about the design of the promising engine. Nonetheless, GE Aviation expects the specific fuel consumption of Affinity engines to be not much higher or even comparable to that of modern turbofan engines of conventional subsonic passenger aircraft. How this will be achieved for supersonic flight is not clear.
Boom / Boom Technologies
Projects
Despite the many projects of supersonic passenger aircraft in the world (including even the unrealizable project of converting the strategic Tu-160 bomber into a passenger supersonic airliner, proposed by Russian President Vladimir Putin), the AS2 of the American startup Aerion, S-512, can be considered the closest to flight tests and small-scale production. Spanish Spike Aerospace and Boom American Boom Technologies. It is planned that the first will fly at a speed of 1.5 Mach number, the second - 1.6 Mach number, and the third - 2.2 Mach number. The X-59 aircraft, created by Lockheed Martin by order of NASA, will be a technology demonstrator and a flying laboratory, it is not planned to launch it into production.
Boom Technologies has already announced that it will try to make flights on supersonic aircraft very cheap. For example, Boom Technologies estimated the cost of a flight on the New York - London route at five thousand dollars. That is how much it costs today to fly this route in business class of an ordinary subsonic liner. Liner Boom over populated land will fly at subsonic speed and go to supersonic over the ocean. The aircraft with a length of 52 meters and a wingspan of 18 meters will be able to carry up to 45 passengers. By the end of 2018, Boom Technologies plans to select one of several new aircraft projects for implementation in metal. The first flight of the liner is planned for 2025. The company has postponed these terms; Boom was originally slated to take off in 2023.
According to preliminary calculations, the length of the AS2 aircraft, designed for 8-12 passengers, will be 51.8 meters, and the wingspan - 18.6 meters. The maximum take-off weight of a supersonic aircraft will be 54.8 tons. AS2 will fly over water at a cruising speed of 1.4-1.6 Mach, slowing to 1.2 over land. A slightly lower flight speed over land, coupled with a special aerodynamic shape of the glider, will allow, as the developers expect, to almost completely avoid the formation of shock waves. The flight range of the aircraft at a speed of 1.4 Mach number will be 7.8 thousand kilometers and 10 thousand kilometers - at a speed of 0.95 Mach number. The first flight of the aircraft is planned for the summer of 2023, and the first transatlantic flight will take place in October of the same year. Its developers will mark the 20th anniversary of the last flight of the Concorde.
Finally, Spike Aerospace plans to begin flight tests of a full-fledged prototype S-512 no later than 2021. Deliveries of the first production aircraft to customers are scheduled for 2023. According to the project, the S-512 will be able to carry up to 22 passengers at speeds up to Mach 1.6. The flight range of this aircraft will be 11.5 thousand kilometers. Since October last year, Spike Aerospace has several scaled-down models of supersonic aircraft. Their purpose is to test the design and effectiveness of flight controls. All three promising passenger aircraft are being built with an emphasis on a special aerodynamic shape that will reduce the intensity of shock waves generated during supersonic flight.
In 2017, the volume of air passenger traffic worldwide amounted to four billion people, of which 650 million made long-distance flights from 3.7 to 13 thousand kilometers. 72 million long-range passengers flew first and business class. It is these 72 million people that the developers of supersonic passenger aircraft are targeting in the first place, believing that they will gladly pay a little more money for the opportunity to spend about half the time in the air than usual. Nevertheless, supersonic passenger aviation is likely to start actively developing after 2025. The fact is that research flights of the X-59 laboratory will begin only in 2021 and will last for several years.
Research results obtained during X-59 flights, including over settlements- by volunteers (their residents agreed to have supersonic planes fly over them on weekdays; after the flights, observers will tell researchers about their perception of noise), it is planned to be submitted to the US Federal Aviation Administration for consideration. As expected, on their basis, it can revise the ban on supersonic flights over the populated part of the land, but this will not happen until 2025.
Vasily Sychev
One example of existing projects of supersonic aircraft.
Today I'll start with a short introduction 🙂.
On this site I already have flying aircraft. That is, the time has come long ago to write something and about supersonic, especially since I promised to do it :-). The other day I got down to work with considerable zeal, but realized that the topic was as interesting as it was voluminous.
Recently my articles do not shine with brevity, I do not know whether this is an advantage or a disadvantage :-). And the issue on the topic “ supersonic"Threatened to become even more and it is not known how long I would have had to" create "it :-).
So I decided to try and make a few articles. A kind of small series (about three or four), in which each component will be devoted to one or two concepts on the topic supersonic speeds... And it will be easier for me, and I will bother readers less :-), and Yandex and Google will be more supportive (which is important, you yourself understand :-)). Well, what will come of it to judge, of course, you ..
********************
So, let's talk today about supersonic and supersonic aircraft... The very concept of “ supersonic"In our language (all the more in a superlative degree) flashes much more often than the term" subsonic ".
On the one hand, this is, in general, understandable. Subsonic aircrafts have long become something completely ordinary in our life. A supersonic aircraft, although they have been flying in airspace for 65 years, they still seem to be something special, interesting and deserving of increased attention.
On the other hand, this is quite fair. After all, flights to supersonic- this is, one might say, a separate area of movement closed by a certain barrier. However, inexperienced people may well have a question: “And what, in fact, is so outstanding in this supersound? What difference does it make when an airplane flies at a speed of 400 km / h or 1400 km / h? Give him a more powerful engine and everything will be fine! " At the dawn of its development, aviation was in approximately this semantic position.
Speed has always been the ultimate dream, and initially these aspirations were quite successfully implemented. Already in 1945, test pilot of the firm Messerschmitt L. Hoffmann in horizontal flight on one of the world's first aircraft with jet engines, ME-262, reached a speed of 980 km / h in horizontal flight at an altitude of 7200 m.
However, in reality, everything is far from so simple. After all, the flight to supersonic differs from subsonic not only in the magnitude of the velocity and not so much in it. The difference here is qualitative.
Already at speeds of the order of 400 km / h, such a property of air as compressibility begins to gradually manifest itself. And, in principle, there is nothing unexpected here. Is gas. And all gases, as you know, unlike liquids, are compressible. Compression changes gas parameters, such as density, pressure, temperature. Because of this, different physical processes can proceed in a compressed gas in a different way than in a rarefied one.
The faster the plane flies, the more it, together with its aerodynamic surfaces, becomes like a kind of piston, in a sense, compressing the air in front of it. Exaggerated, of course, but in general it is like that :-).
With an increase in speed, the aerodynamic picture of the flow around the aircraft changes and the faster, the more :-). And on supersonic it is already qualitatively different. At the same time, new concepts of aerodynamics come to the fore, which often simply do not make any sense for low-speed aircraft.
To characterize the flight speed, it now becomes convenient and necessary to use such a parameter as the M number (Mach number, the ratio of the aircraft speed relative to the air at a given point to the speed of sound in the air flow at this point). Another type of aerodynamic drag appears and becomes perceptible (very perceptible!) wave impedance(along with the already increased conventional drag).
Phenomena such as a wave crisis (with a critical number M) become significant supersonic barrier, shock waves and shock waves.
In addition, the controllability and stability characteristics of the aircraft deteriorate due to the rearward displacement of the point of application of aerodynamic forces.
When approaching the region of transonic speeds, the aircraft can experience strong shaking (this was more typical for the first aircraft that stormed the then mysterious boundary of the speed of sound), similar in its manifestations to another very unpleasant phenomenon that aviators had to face in their professional development. This phenomenon is called flutter (topic for another article :-)).
There is such an unpleasant moment as the heating of the air as a result of its sharp braking in front of the aircraft (the so-called kinetic heating), as well as heating as a result of viscous air friction. At the same time, the temperatures are quite high, about 300 ° C. The skin of an aircraft is heated to such temperatures during a long supersonic flight.
We will definitely talk about all the concepts and phenomena mentioned above, as well as the reasons for their occurrence in other articles in more detail. But now so, I think it is quite clear that supersonic- this is something completely different than flying at subsonic (all the more low) speed.
In order to get along with all the newly emerging effects and phenomena at high speeds and fully correspond to its purpose, the aircraft must also change qualitatively. Now it should be supersonic aircraft, that is, an aircraft capable of flying at a speed exceeding the speed of sound in a given section of airspace.
And for him it is not enough just to increase the engine power (although this is also a very important and obligatory detail). These planes usually change their appearance. Sharp corners and edges, straight lines appear in their appearance, in contrast to the "smooth" outlines of subsonic aircraft.
Supersonic aircraft have a swept or triangular wing. A typical and one of the most famous delta wing aircraft is the remarkable MiG-21 fighter (maximum speed at an altitude of 2230 km / h, at sea level 1300 km / h).
Supersonic aircraft with a triangular wing MIG-21.
One of the swept-like options is an ogival wing with an increased lift coefficient. It has a special inflow near the fuselage, designed to form artificial spiral vortices.
MIG-21I with an ogival wing.
MIG-21I - ogival wing.
Live wing TU-144.
It is interesting that a wing of this type, later installed on the TU-144, was tested on a flying laboratory based on the same MIG-21 (MIG-21I).
The second option is supercritical wing... It has a flattened profile with a curved rear end in a certain way, which makes it possible to postpone the occurrence of a wave crisis at high speeds and can be beneficial in terms of economy for high-speed subsonic aircraft. Such a wing is used, in particular, on the SuperJet 100 aircraft.
SuperJet 100. An example of a supercritical wing. The bend of the profile is clearly visible (back)
Photos are clickable.
After a person began to master the heavenly expanses, he always tried to improve aircraft as much as possible, to make them more reliable, faster, and more spacious. One of the most advanced inventions of mankind in this direction are supersonic passenger aircraft. But, unfortunately, with rare exceptions, most of the developments have been closed or are currently at the project stage. One of these projects is the Tu-244 supersonic passenger aircraft, which we will discuss below.
Faster than sound
But before we start talking directly about the Tu-244, let's do short excursion in the history of overcoming the speed of sound by mankind, because this aircraft will be a direct continuation of scientific developments in this direction.
A significant impetus in the development of aviation was given by the Second World War. It was then that real projects of aircraft with more propeller-driven speeds appeared. Since the second half of the 40s of the last century, they have been actively adopted both in military and civil aviation.
The next task was to maximize it. If it was not difficult to reach the supersonic barrier, simply by increasing the power of the engines, then overcoming it was a significant problem, since the laws of aerodynamics change at such speeds.
Nevertheless, the first victory in the race with sound was achieved already in 1947 on an American experimental aircraft, but supersonic technologies began to be massively used only in the late 50s - early 60s of the XX century in military aviation. Production models such as the MiG-19, North American A-5 Vigilante, Convair F-102 Delta Dagger and many others appeared.
Passenger supersonic aviation
But civil aviation was so unlucky. The first supersonic passenger aircraft appeared only in the late 60s. And to date, only two production models have been created - the Soviet Tu-144 and the Franco-British "Concorde". These were typical long-haul aircraft. The Tu-144 was in service from 1975 to 1978, and the Concorde from 1976 to 2003. Thus, at the moment, no supersonic aircraft is used for passenger air transportation.
There were many projects for the construction of super- and hypersonic airliners, but some of them were eventually closed (Douglas 2229, Super-Caravelle, T-4, etc.), and the implementation of others stretched out indefinitely (Reaction Engines A2, SpaceLiner, Next Generation Supersonic Transport). The latter also includes the Tu-244 aircraft project.
Development start
The project to create an aircraft that was supposed to replace the Tu-144 was launched by the Tupolev Design Bureau back in Soviet times, in the early 70s of the last century. When designing a new airliner, the designers used the developments of its predecessor, the Concorde, as well as materials from American colleagues who took part in the work. All developments were carried out under the direction of Alexei Andreevich Tupolev.
In 1973, the projected aircraft was named Tu-244.
Project objectives
The main objective of this project was to create a truly competitive supersonic aircraft for passenger transport compared to subsonic jet airliners. Almost the only advantage of the former over the latter was the gain in speed. In all other respects, supersonic airliners were outperformed by their slower competitors. Passenger transportation on them simply did not pay off economically. In addition, flights on them were more dangerous than on simple aircraft with a jet engine. The latter factor, by the way, became the official reason why the operation of the first supersonic Tu-144 aircraft was terminated just a few months after its start.
Thus, it was the solution to these problems that was presented to the developers of the Tu-244. The plane should be reliable, fast, but, at the same time, its operation for the transport of passengers should have been economically profitable.
Specifications
The final model of the Tu - 244 aircraft, adopted for development, was supposed to have the following technical and operational characteristics.
The crew of the airliner included three people. The cabin capacity was taken at the rate of 300 passengers. True, in the final version of the project it had to be reduced to 254 people, but in any case it was much more than that of the Tu-154, which accommodated only 150 passengers.
The planned cruising speed was 2.175 thousand km / h, which was twice as high. For comparison, the same figure for the Tu-144 was 2.300 thousand km / h, and for the Concorde - 2.125 thousand km / h. That is, it was planned to make the plane a little slower than its predecessor, but due to this, to significantly increase its capacity, which was supposed to provide economic benefits from passenger transportation. The movement was provided by four. The flight range of the new aircraft was supposed to be 7500-9200 km. Carrying capacity - 300 tons.
The airliner was supposed to have a length of 88 m, a height of 15 m, while its wingspan was 45 m, and its working surface area was 965 m 2.
The main external distinction from the Tu-144 was supposed to be a change in the design of the nose.
Continued development
The project for the construction of a second-generation supersonic airliner Tu-244 took on a rather protracted nature and underwent significant changes several times. Nevertheless, even after the collapse of the USSR, the Tupolev Design Bureau did not stop developing in this direction. For example, already in 1993, at the air show in France, detailed information about the development was provided. However, economic situation countries in the 90s could not but affect the fate of the project. In fact, his fate hung in the air, although design work continued, and there was no official announcement of its closure. It was at this time that American specialists began to actively join the project, although contacts with them were carried out back in the days of the USSR.
To continue research on the creation of second generation passenger supersonic airliners, in 1993 two Tu-144 aircraft were converted into flying laboratories.
Closing or freezing?
Against the background of ongoing developments and statements that by 2025 TU-244 aircraft will enter service in civil aviation in the amount of 100 units, the absence of this project in the state program for the development of aviation for 2013-2025, which was adopted in 2012, was quite unexpected. ... It must be said that this program also lacked a number of other notable developments that were considered promising in aircraft construction until that time, for example, the Tu-444 supersonic business aircraft.
This fact could indicate that the Tu-244 project was either finally closed or frozen for an indefinite period. In the latter case, the release of these supersonic aircraft will only be possible much later than 2025. However, no official clarifications on this matter have been given, which leaves a fairly wide field for various interpretations.
Perspectives
Considering all of the above, it can be stated that the Tu-244 project is currently at least suspended in the air, and, possibly, completely closed. There has not yet been an official announcement about the fate of the project. Also, the reasons why it was suspended or permanently closed are not voiced. Although it can be assumed that they may lie in the lack of public funds to finance such developments, the economic disadvantage of the project, or the fact that in 30 years it could simply become morally obsolete, and now more promising tasks are on the agenda. However, the influence of all three factors is quite possible at the same time.
In 2014, the media suggested the resumption of the project, but so far they have not received official confirmation, as well as denials.
It should be noted that foreign developments of second-generation supersonic passenger aircraft have not yet reached the home stretch, and the implementation of many of them is a big question.
At the same time, while there is no official statement from authorized persons, it is not worth completely putting an end to the Tu-244 aircraft project.
On the field supersonic aviation no one was left. It is unclear whether such aircraft are not needed (unprofitable), or our civilization has not yet reached such technical perfection and reliability in this direction.
Small private projects are starting to appear.
The American company "Aerion Corporation" from the small town of Reno, Nevada, has begun accepting orders for the creation of a private supersonic aircraft "AS2 Aerion", which is being built with the support of Airbus
It is not clear yet what will come of it, but here are the details ...
The manufacturer claims that its patented laminar flow technology reduces aerodynamic drag over the wings by up to 80%, allowing the three-engine powerplant to cover distances quickly. For example, from Paris to Washington, the plane will fly in just three hours, and from Singapore to San Francisco, in just six hours. Supersonic flights over US territory are prohibited, but this does not apply to flights over the ocean. The body of the aircraft is mainly made of carbon fiber and is "sewn" along the seam with a titanium alloy. Without refueling, the plane can fly up to 5400 miles. The production of the first aircraft is planned for 2021.
What projects of supersonic aircraft have not found their embodiment in reality? Well, for example, the most serious ones:
Sukhoi Supersonic Business Jet (SSBJ, S-21) - project of supersonic passenger aircraft business class developed by the Sukhoi Design Bureau. In search of financing, Sukhoi OJSC collaborated on this project with Gulfstream Aerospace, Dassault Aviation, as well as a number of Chinese companies.
The development of the S-21 and its larger modification S-51 was started in 1981 at the initiative of the chief designer of the Sukhoi Design Bureau at that time, Mikhail Petrovich Simonov. The project was headed by Deputy Chief Designer Mikhail Aslanovich Pogosyan.
An analysis of the commercial operation of Tu-144 and Concorde aircraft showed that with the rise in prices for aviation fuel, supersonic aircraft cannot compete with more economical subsonic airliners in the segment of mass transportation. The number of passengers who are ready to significantly overpay for the speed of movement is small and is determined mainly by representatives of large business and senior officials. At the same time, the priority traffic routes are the airlines connecting the world capitals. This defined the concept of the aircraft as designed to carry 8-10 passengers at a distance of 7-10 thousand kilometers (to provide a non-stop flight between cities on the same continent and with one refueling when flying from any to any capital of the world). It was also important to reduce the length of the run, so that the aircraft could receive all international airports the world.
In the course of work on the aircraft, various configuration options were worked out - with 2, 3 or 4 engines. The collapse of the Soviet Union led to the cessation of funding for the program from the state. Sukhoi Design Bureau began searching for independent investors for the project. In particular, in the early 1990s, the work was carried out in cooperation with American company Gulfstream Aerospace - at the same time, a variant with 2 English engines was being worked out, which received the designation S-21G. However, in 1992, the American side withdrew from the project, fearing unaffordable costs. The project has been put on hold.
In 1993, investors for the project were found in Russia and the project was resumed. Received US $ 25 million from investors helped to reach the design completion stage. Ground tests of engines were carried out, as well as tests of aircraft models in wind tunnels.
In 1999, the aircraft project was presented at the Le Bourget air show, at the same time Mikhail Petrovich Simonov said that about 1 billion dollars would be required to complete all work on the aircraft and start production of serial liners. With timely and full funding, the aircraft could take off for the first time in 2002, and the unit cost would be about $ 50 million. The possibility of continuing joint work on the project with the French company Dassault Aviation was considered, but the contract did not materialize.
In 2000, the Sukhoi Design Bureau tried to find investors for this project in China.
Currently, no investments have been found to complete the development and creation of aircraft. In the state program adopted at the end of 2012 "Development aviation industry for 2013 - 2025 "there is no mention of the aircraft
ZEHST(short for Zero Emission HyperSonic Transport- English. High-speed, zero-emission transport) is a project of a supersonic-hypersonic passenger airliner, implemented under the leadership of the European aerospace agency EADS.
The project was first presented on June 18, 2011 at the Le Bourget air show. According to the project, it is assumed that the plane will accommodate 50-100 passengers and reach speeds of up to 5029 km / h. The flight altitude should be up to 32 km.
The aircraft's jet system will consist of two turbojet engines used in the take-off and acceleration section up to 0.8M, then the rocket upper stages will accelerate the aircraft to 2.5M, after which two ramjet engines located under the wings will bring the speed to 4M.
Tu-444- a project of a Russian supersonic business aviation passenger aircraft developed by JSC Tupolev. It replaced the Tu-344 project and a competitor to the Sukhoi design bureau SSBJ. In the state program "Development of the aviation industry for 2013-2025" adopted at the end of 2012, there is no mention of the project
The design of the Tu-444 began in the early 2000s, and in 2004 a preliminary study of the project began. The development was preceded by a miscalculation of the most profitable technical characteristics for an aircraft of this class. So, it was found that a range of 7,500 kilometers is enough to cover the main business centers of the world, and the optimal takeoff run length is 1,800 meters. The potential market was estimated at 400-700 aircraft, the first flight according to the plan was supposed to take place in 2015
Nevertheless, despite the use in the project of old developments of a number of design bureaus, including Tupolev itself (for example, Tu-144, it was supposed to use AL-F-31 engines), the need for a number of technical innovations became clear, which turned out to be impossible without significant financial investments. that failed to attract. Despite the elaboration of a preliminary design by 2008, the project "stalled".
Well, and a little more aviation topics for you: let's remember, but this one. And you know that it exists and flew like that. Here is also unusual The original article is on the site InfoGlaz.rf The link to the article this copy was made from is
