M \u003d 1.2-5).
History
The 60s-70s of the XX century were marked by the rapid development of supersonic aviation. The main problems of stability and controllability of aircraft, their aerodynamic efficiency were solved. The high flight speed also made it possible to increase the ceiling over 20 km, which was important for reconnaissance aircraft and bombers (at that time, before the appearance of anti-aircraft missile systems capable of hitting targets at high altitudes, the main principle of using bombers was to fly to the target at the highest possible height and speed). During these years, supersonic aircraft for various purposes were built and put into mass production: fighters (tactical and interceptors), bombers, fighter-bombers, reconnaissance aircraft (the first supersonic all-weather interceptor - Convair F-102 Delta Dagger; the first supersonic long-range bomber - Convair B -58 Hustler).
Nowadays, new aircraft appear, including those made using the Stealth technology.
Comparative schemes of Tu-144 and "Concorde"
Passenger supersonic aircraft
Only two mass-produced supersonic passenger aircraft are known to perform regular flights: Soviet aircraft Tu-144, which made its first flight on December 31, 1968 and was in operation from 1975 to 1978, and performed two months later - on March 2, 1969 - its first flight of the Anglo-French Concorde, which made transatlantic flights from 1976 to 2003 year. Their operation made it possible not only to significantly reduce the flight time on long-haul flights, but also to use unloaded air space at high altitudes (≈18 km), while the main airspace used by liners (altitudes of 9-12 km) was already heavily loaded in those years. Also, supersonic aircraft flew on straightened routes (outside airways).
Despite the failure to implement several other former and existing projects of passenger supersonic and transonic aircraft (Boeing 2707, Boeing Sonic Cruiser, Douglas 2229, Lockheed L-2000, Tu-244, Tu-344, Tu-444, SSBJ, etc.) and withdrawal from the operation of aircraft of the two implemented projects, were developed earlier and there are modern projects of hypersonic (including suborbital) passenger airliners (for example, ZEHST, SpaceLiner) and military transport (landing) rapid response aircraft. The Aerion AS2 passenger business jet under development was firmly ordered in November 2015 for 20 units with a total cost of $ 2.4 billion, with deliveries starting in 2023.
Theoretical problems
Flight at supersonic speed, in contrast to subsonic, proceeds under conditions of different aerodynamics, since when the aircraft reaches the speed of sound, the aerodynamics of the flow qualitatively changes, which sharply increases the aerodynamic drag, and the kinetic heating of the structure also increases from the friction of the incoming air flow at high speed. , the aerodynamic focus shifts, which leads to the loss of stability and controllability of the aircraft. In addition, such a phenomenon, unknown before the creation of the first supersonic aircraft, manifested itself as “wave drag”.
Therefore, the achievement of the speed of sound and effective stable flight at near- and supersonic speeds were impossible due to a simple increase in engine power - new design solutions were required. As a result, the appearance of the aircraft has changed: characteristic straight lines, sharp corners have appeared, in contrast to the "smooth" forms of subsonic aircraft.
It should be noted that the problem of creating an efficient supersonic aircraft cannot be considered solved until now. The creators have to make a compromise between the requirement to increase the speed and maintain acceptable takeoff and landing characteristics. Thus, the conquest by aviation of new frontiers in speed and altitude is associated not only with the use of a more advanced or fundamentally new propulsion system and a new structural layout of aircraft, but also with changes in their geometry in flight. Such changes, while improving the characteristics of the aircraft at high speeds, should not degrade their quality at low speeds, and vice versa. Recently, the creators refuse to reduce the wing area and the relative thickness of their profiles, as well as to increase the wing sweep angle in aircraft with variable geometry, returning to the wings of small sweep and large relative thickness, if satisfactory values \u200b\u200bof the maximum speed and practical ceiling have already been achieved. In such a case, it is considered important that the supersonic aircraft has good flight performance at low speeds and low drag at high speeds, especially at low altitudes.
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Nowadays, new aircraft appear, including those made using the Stealth technology.
Passenger supersonic aircraft
There are only two mass-produced supersonic passenger aircraft that performed regular flights: the Soviet Tu-144, which made its first flight on December 31, 1968 and was in operation from to 1978 and completed its first flight in England two months later, on March 2, 1969. French "Concorde" (French Concorde - "consent"), making transatlantic flights from 2003 to 2003. Their operation allowed not only to significantly reduce the flight time on long-haul flights, but also to use unloaded airspace at high altitudes (≈18 km), while the main airspace used by liners (altitudes of 9-12 km) was already strong in those years. loaded. Also, supersonic aircraft flew on straightened routes (outside airways).
Despite the failure to implement several other former and existing projects of passenger supersonic and transonic aircraft (Boeing 2707, Boeing Sonic Cruiser, Douglas 2229, Lockheed L-2000, Tu-244, Tu-344, Tu-444, SSBJ, etc.) and withdrawal from the operation of the aircraft of the two implemented projects, were developed earlier and there are modern projects of hypersonic (including suborbital) passenger airliners (e.g., ZEHST, SpaceLiner) and military transport (landing) rapid response aircraft. The Aerion AS2 passenger business jet under development was firmly ordered in November 2015 for 20 units with a total cost of $ 2.4 billion, with deliveries starting in 2023.
Theoretical problems
Flight at supersonic speed, in contrast to subsonic, proceeds under conditions of different aerodynamics, since when the aircraft reaches the speed of sound, the aerodynamics of the flow qualitatively changes, which sharply increases the aerodynamic drag, and the kinetic heating of the structure also increases from the friction of the incoming air flow at high speed. , the aerodynamic focus shifts, which leads to the loss of stability and controllability of the aircraft. In addition, such a phenomenon, unknown before the creation of the first supersonic aircraft, manifested itself as "wave drag".
Therefore, the achievement of the speed of sound and effective stable flight at near and supersonic speeds were impossible due to a simple increase in engine power - new design solutions were required. As a result, the appearance of the aircraft has changed: characteristic straight lines, sharp corners have appeared, in contrast to the "smooth" forms of subsonic aircraft.
It should be noted that the problem of creating an efficient supersonic aircraft cannot be considered solved until now. The creators have to make a compromise between the requirement to increase the speed and maintain acceptable takeoff and landing characteristics. Thus, the conquest by aviation of new frontiers in speed and altitude is associated not only with the use of a more advanced or fundamentally new propulsion system and a new structural layout of aircraft, but also with changes in their geometry in flight. Such changes, while improving the characteristics of the aircraft at high speeds, should not degrade their quality at low speeds, and vice versa. Recently, the creators refuse to reduce the wing area and the relative thickness of their profiles, as well as to increase the wing sweep angle in aircraft with variable geometry, returning to the wings of small sweep and large relative thickness, if satisfactory values \u200b\u200bof the maximum speed and practical ceiling have already been achieved. In such a case, it is considered important that the supersonic aircraft has good flight performance at low speeds and low drag at high speeds, especially at low altitudes.
Development of a supersonic passenger aircraft the second generation, abbreviated SPS-2, is entering its final phase. The first flight of the Tu-244 is expected by 2025. The new Russian commercial airliner will be structurally different from the Soviet Tu-144 in terms of characteristics, flight range, comfort, capacity, size, engine power, and avionics. Its supersonic speed of Mach 2 will remain the same as that of the predecessor Tu-144LL "Moscow", it is still the best indicator in the world in heavy civil aircraft construction. At an altitude of 20 km, the routes are free.
A limitation for aircraft designers and developers may be the length of the 1st class runway, at least 3 km is required. Such concrete strips are not found in all airports in the world and in the country. There can be no illusions about the fact that the best aircraft will not be in demand by Western countries, which are more interested in selling their European Airbus and American Boeing, flying at a speed of 700 - 900 km / h, 2.5-3 times slower. You will have to rely only on the needs of Russia and the BRICS, as well as on wealthy customers who can afford such aircraft.
Project objectives
The first Tu-244 model is expected to see the proven NK-32 engines, the same as those of the Tu-160M2 strategic bomber upgraded on 11/16/2017. The very first development of the SPS-2 began too early, in 1973, thanks to the achievements of Soviet military designers in the 1950s, 50 years ahead of their time. At that time, there were still no such high-quality composite materials to use them in large quantities, and the power plants had insufficient traction. In the 1960s, there were engines with a 20-ton thrust, in the 1970s with a 25-ton thrust, and now 32-ton engines are used.
Aircraft designers have 2 main tasks:
Flight range - 9,200 km.
Reduced fuel consumption for this class of equipment.
The first and second tasks can be solved by the example of the Tu-160 and Tu-22M3, using a variable sweep of the wing, making the aircraft multi-mode. You can analyze the closed projects T-4 and T-4MS Chernyakov, study the development of Myasishchev on modifications of the M-50, ingenious and fantastic then, more suitable today. The Tupolev Design Bureau has everything for this, it contains materials from all the leading design bureaus of the USSR involved in heavy strategic aviation, on the basis of which the world's best military "long-range" Tu-22M3M and Tu-160M2 were created.
The advantages of jet aircraft
Advantage jet aircraft - speed. This guarantees a comfortable flight and shortens the distance in time. Spending three times less hours in a chair is a good health of passengers, for example, on the Vladivostok-Kaliningrad flight. Business time is saved. Using the services of the Tu-244 airliner, you can spend 1 day more on vacation, and, upon arrival, immediately go to work without fatigue. It is also important to receive moral satisfaction from our citizens from the prestige of the Tu-244, to feel pride in Russia. The release of civilian jet aircraft from the military-industrial complex of the Russian Federation is more significant than the self-sufficiency of the country's defense enterprises, it is a commercial focus, jobs, a guarantee of stability and the accumulation of profits in harsh market conditions.
Disadvantages of Bullet Passenger Airliners
In the Tupolev Design Bureau in the 1960s, they noticed that the creation of a civil supersonic passenger liner according to military principles, it will not work because of the requirements for comfort and security. We began to study in this regard the experience of the USA, France and England, which was considered the best, then, according to the plan of the chief designer Alexei Andreevich Tupolev, went into operation. The disadvantages of the first Tu-144 and "Concorde" are high fuel consumption, loudness of the engine, sound booms, the amount of harmful emissions into the atmosphere.
The main disadvantage of the Tu-244 is the commercial, military and political institutions of the West, because their Concordes flew off in 2003, and there are no new ones in the plans, because our aircraft construction paths diverge. The explanation for this: firstly, NATO does not need strategic supersonic aviation, because at the heart of their power is an aircraft-carrying oceanic fleet, and nuclear bombs and missiles are enough to deliver by aircraft with a range of 1.5 km (fighters) from military bases scattered around the world, which is why military projects of this class in the west are not very in demand. Also, the rather high cost of the flight sharply narrows the potential market segment for these aircraft, so there can be no question of mass production. However, a simultaneous order for the military and passenger transportation, this is exactly what can give a serious boost to supersonic passenger aviation.
What will be the Tu-244 in terms of flight performance
The design was delayed, the Tu-144 in the 1968 configuration reached its first design characteristics by the mid-1970s. Work on its improvement since 1992 - the beginning of the Tu-244 project, since then 25 years have passed, to complete what has been started it will take 10 more. It is clearly seen that the involvement of the United States, England and France in the development of the Tu-244 program with the collapse of the USSR they did not lead to anything good, as in all similar cases in the former USSR. Only the collection of scientific data from the Tu-144LL for the NASA military space program and the slowdown of our enterprises in development.
Today there are many options for Tu-244 projects. No one can say exactly what the plane will be like. Unofficial sources spread ambiguous information. The characteristics described below are conditional, based on current capabilities. Characteristics: length 88.7 m; a wingspan of 54.77 m, an area of \u200b\u200b1,200 square meters, and an aspect ratio of 2.5 m; wing sweep along the edge - at the center section 75 degrees, - at the console 35 degrees; fuselage width 3.9 m, height 4.1 m, luggage compartment 32 sq. m .; takeoff weight 350 t, including fuel 178 t; engines NK-32 - 4 units; cruising speed 2.05 M; range of 10 thousand km; Max. height 20 km.
Airframe Tu-244
Imagine a trapezoidal wing and a complex deformation of its middle trapezoid. Aileron control in balance, roll and pitch. The socks are mechanically deflected at the leading edge. The wing structure is divided into parts, front, middle and console. The middle and cantilever parts with multi-spar and multi-thread power circuits, there are no front ribs. The vertical tail is the same as in the wing structure and the two-piece steering rudder.
Fuselage with pressurized cabin, nose and tail compartments - the dimension will be selected on order based on the number of passenger seats. For 250 and 320 passengers, the fuselage diameter from 3.9 to 4.1 m is suitable. The cabin will be divided into classes, 1st, 2nd and 3rd. In terms of comfort, the Tu-244 will be at the level of the latest modification of the Tu-204. The aircraft is equipped with a cargo compartment. Four pilots, their seats with catapults (in Russian), shoot upwards. On board everything is re-automated and subordinated to the central program control.
Tu-244 may lose a deflectable nose, similar to Tu-144LL, due to the development of the latest optoelectronic equipment and the possibility of deflecting the vectors of controlled thrust in modern domestic power plants. In places of maximum load, titanium alloy VT-64 can be used in the area of \u200b\u200bthe wheel. The nose strut may remain the same, as if there will be 3 new main supports for the concrete strip, designed for high loads. Navigation and flight equipment will correspond to the meteorological minimum according to the international classification IIIA ICAO.
The idea of \u200b\u200bRussian President Vladimir Putin, inspired by the flight of the new "White Swan", to create a supersonic aircraft made not only employees of the Kazan Aircraft Building Plant think about it, but also many other observers. Can a missile carrier inspire designers to create new types of supersonic aircraft?
The largest and most powerful supersonic aircraft Tu-160 in the history of military aviation, known to many by the nickname "White Swan", has recently received a new life. For the first time in many years, the Kazan Aircraft Building Plant presented to the public an updated Tu-160M \u200b\u200bbomber, named in honor of the first Commander-in-Chief of the Russian Air Force, Peter Deinekin.
The first flight of the missile carrier was personally observed by the Supreme Commander-in-Chief of the Russian Armed Forces and Russian President Vladimir Putin. The head of state was deeply impressed by the flight of the new "White Swan" and highly appreciated the professionalism of the pilots performing the maneuver, asking them to thank the pilots even before the aircraft landed. There was nothing surprising in the president's emotions, since Putin himself piloted the Tu-160 missile carrier back in 2005.
Upon completion of the flight, the President made a proposal to Kazan aircraft designers to create on the basis of the new Tu-160M \u200b\u200bversion of the passenger supersonic "Swan" for civil aviation.
But in order to understand how realistic it is to realize the idea of \u200b\u200bVladimir Putin, one should turn to the history of Russian aviation and recall what steps have already been taken by aircraft designers in this direction.
Tu-144
One of the greatest industrial successes in Russian history was the creation of the Tu-144. It was manufactured long before the Tu-160 and became the first supersonic passenger airliner in the history of mankind. In addition, the Tu-144 is still one of two famous stories types of supersonic passenger aircraft.
The airliner was created on the instructions of the Council of Ministers of the USSR, released on July 19, 1963. Serious demands were placed on the first supersonic passenger aircraft. The plane was supposed to be able to fly at a cruising speed of 2300 to 2700 km / h for a distance of up to 4500 kilometers, while carrying up to 100 passengers on board.
The first prototype of the aircraft was created by the Tupolev Design Bureau in 1965. Three years later, the plane took to the skies for the first time, two months ahead of the main and only competitor - the famous British-French Concorde.
The Tu-144 had a number of design features that even outwardly markedly distinguished it from other aircraft. There were no flaps or slats on its wings: the aircraft reduced speed due to the deflecting nose of the fuselage. In addition, the ancestor of modern GPS navigators was installed on the airliner - the PINO (Projection Navigation Situation Indicator) system, which projected the necessary coordinates onto the screen from a filmstrip.
However, due to the too high costs of operating and maintaining the airliner, the Soviet Union abandoned further production of the Tu-144. By the time the production was canceled, only 16 aircraft remained, two of which were later destroyed in the infamous disaster at the international air show at Le Bourget in 1973 and in the crash over Yegoryevsk in 1978. On this moment there are only eight aircraft left in the world assembled, three of which can be fully restored and ready for further use.
SPS-2 and Tu-244
Photo: Stahlkocher / wikimedia.org
Another project that had serious expectations was the SPS-2, which was later given the promising name of Tu-244 by the Tupolev Design Bureau.
The first information about work on the second generation supersonic passenger airliner dates back to about 1971 - 1973 of the last century.
When developing the Tu-224, the designers took into account both the experience in the creation and operation of its predecessors - Tu-144 and Concorde, and Tu-160, as well as American projects of supersonic aircraft.
As conceived by the developers of the SPS-2, the new airliner was to lose the main "business card" of its predecessor - the forward deflecting fuselage. In addition, the glazing area of \u200b\u200bthe cockpit had to be reduced to a minimum sufficient for visibility. For takeoff and landing of the aircraft, it was planned to use an optical-electronic review system.
Also, the projected aircraft was supposed to rise to an altitude of 20 kilometers and accommodate about 300 passengers on board. To achieve such parameters, it was necessary to dramatically increase its size in all respects, which was planned to be done: with a fuselage length of almost 90 meters and a wingspan of about 50 meters, the Tu-244 would look like a giant against the background of any existing analogues.
But the maximum speed of the airliner, in comparison with its predecessors, practically remained the same: the speed limit of the SPS-2 did not exceed 2500 km / h. In contrast, it was planned to increase the maximum flight distance to about 9000 kilometers by reducing the volume of fuel consumption.
However, the production of such a supersonic heavyweight in the realities of the modern world turned out to be economically inexpedient. In view of the increased requirements for environmental standards, the cost of operating such a Tu-244 aircraft at the moment is unaffordable both for the aircraft manufacturer itself and for the country's economy as a whole.
Tu-344 and Tu-444
These aircraft were developed by the Tupolev Design Bureau (later Tupolev OJSC, now Tupolev PJSC) as a response to the growing worldwide demand for fast and small business-class aircraft. This is how various projects of SBS - supersonic business aircraft appeared.
Such aircraft were supposed to be small and capable of carrying about 10 passengers. The first SBS project from Tupolev - Tu-344 - was planned to be manufactured back in the 90s of the last century on the basis of the Tu-22M3 military supersonic bomber. But its development turned out to be a failure in the initial stages, since for international flights the aircraft also had to meet high requirements in the area, which it did not meet already at the first stages of the project development. Therefore, the designer refused further work on the creation of the Tu-344.
Work on the project of its successor, the Tu-444, began in the early 2000s, its development reached the stage of the first sketches. Despite the fact that environmental problems were resolved, the project required the attraction of large financial investments, but Tupolev failed to find investors interested in this.
S-21 (SSBJ)
Photo: Slangcamm / wikimedia.org
The only domestic project to create a supersonic aircraft for civil aviation, which was not developed by the Tupolev Design Bureau, was the C-21 aircraft project, also known as the Sukhoi Supersonic Business Jet (SSBJ).
Work on this project of the Sukhoi Design Bureau began in the 80s. The design bureau understood that the demand for large supersonic airliners had dropped since the Concorde and Tu-144 times and would only decline in the future for reasons of economy. Therefore, the designers of Sukhoi were among the first to come up with the idea of \u200b\u200bcreating a supersonic business aircraft designed for non-stop flights between world capitals.
But the development of the S-21 was prevented by the collapse of the USSR, along with which state funding for the project ceased.
After the collapse of the Soviet Union, Sukhoi tried for many years to attract private investors to the project in Russia and abroad. The volume of incoming investments made it possible to conduct the first tests of engines for the C-21 in 1993.
But to complete the creation and start of serial production of the aircraft, according to the statement of Mikhail Simonov, who at that time was the head of "Sukhoi", required another $ 1 billion, but the company could not find new investors.
There was no one left on the field of supersonic aviation. It is unclear whether such airplanes 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, began accepting orders for the creation of a private supersonic aircraft "AS2 Aerion", which is being created 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 power plant on three engines, cover distances quickly enough. 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 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) - a project of a supersonic business-class passenger aircraft developed by the Sukhoi Design Bureau. In search of funding, 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, the S-51, was launched 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 determined the concept of the aircraft as designed to carry 8-10 passengers at a distance of 7-10 thousand kilometers (to ensure 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, work was carried out in cooperation with the American company Gulfstream Aerospace - while 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 relaunched. 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. The state program "Development of the aviation industry for 2013 - 2025" adopted at the end of 2012, does not mention the aircraft.
ZEHST (short for Zero Emission HyperSonic Transport - English. High-speed transport with zero emissions) 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 jet system of the aircraft will consist of two turbojet engines used in the take-off and acceleration section up to 0.8M, then the rocket boosters will accelerate the aircraft to 2.5M, after which two ramjet engines located under the wings will bring the speed to 4M.
Tu-444 - the project of the 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. The state program "Development of the Aviation Industry for 2013-2025" adopted at the end of 2012, does not mention 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 7500 kilometers is enough to cover the main business centers of the world, and the optimal takeoff run length is 1800 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 which 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's another unusual The original article is on the site InfoGlaz.rf The link to the article this copy was made from is
