The updated Tu-160 bomber made its first flight
The first flight of the Tu-160M with serial engines of the improved NK-32-02 model took place on November 3. This is an important stage not only for the strategic bomber program – the largest combat aircraft (maximum take-off weight of 275 tons) in the history of world aviation.
These engines can also be installed during remotorization on smaller Tu-22M3 bombers, sometimes classified as "eurostrategic". And the NK-32-02 gas generator is of interest as a base for creating domestic engines for remotorization of the fleet of an-124 Ruslan military transport aircraft of the Russian aerospace forces, as well as new vehicles for military and civil aviation. In addition, it can serve as a source of technology in the development of an engine for a promising supersonic airliner. This idea was expressed in January 2018 by the President of Russia, talking with employees of the aircraft factory in Kazan, where all the supersonic bombers developed by the Tupolev design Bureau were built.
The NK-32 is the most powerful dual-circuit turbojet engine ever used on combat aircraft in the world. Thrust in afterburner mode is 25 tons. Mass-dimensional parameters of the product are impressive: weight 3650 kg, length 7.45 m, diameter 1.7 m. Development, testing, production and serial construction of aircraft engines of such a large dimension require huge costs. You can get a greater effect from them by expanding the range of aircraft equipped with them and increasing their output.
Meanwhile, only 35 Tu-160 bombers have been built to date. Of these, 16 remain in service with the Russian aerospace forces, and four more are being tested, refined, and stored. Defense Minister Sergei Shoigu, visiting the Kazan plant five years ago, announced plans for his Department to purchase a series of 50 improved Tu-160M2 From a local aircraft factory.
Apparently, the Russian defense Ministry will implement this plan step by step. During a working trip to Kazan on January 25, 2018, President Putin watched a demonstration flight of a bomber with the proper name "Pyotr Deinekin", a prototype of the future Tu – 160M2, which had just entered testing. Speaking with representatives of the plant's construction team, the Supreme commander-in-chief noted that the initial order placed by the Ministry of defense for 10 Tu-160M2 with a total cost of 160 billion rubles will allow loading the production capacity of the enterprise until 2027. "There is something to do! I congratulate you all. This is a serious step in the development of the high-tech sector and in strengthening the country's defense capability, " Vladimir Putin said at the time.
The head of state recalled that the Tu-160 type of missile carriers are part of the nuclear triad, and the new modification with the suffix " M2 " – " this is a completely different machine. Externally, it looks the same, but the engine and range, power – everything is different."
Putin added that he remembers well the flight he made in 2005 on the Tu-160: "an Unforgettable experience, I said then, and I can repeat it now: like in a dream. The pilots can be envied to a certain extent."
And this is true, because today the Tu-160 and Tu-22M3 are the only mass-produced long-range supersonic bombers in service in the world. Previously, the United States had a small number of supersonic FB-111A, but all aircraft of this type were withdrawn from service at the end of the last century. Today, America has only a B-1B, but it can only be considered supersonic: the allowed speed at high altitude is limited to the value of Mach 1.25, at earth-0.96. Such modest figures were established due to errors in the design of the original B-1A, designed for Mach 2.2. It was tested, but not adopted, and used as a base for creating the B-1B, much less ambitious in speed.
Ahead of the entire planet
Today, Russia is ahead of everyone in the field of heavy supersonic aircraft. Work on them began in the 50s of the last century. The first domestic projects were the M-50 and Tu-22.
The product of the Myasishchev design Bureau was a four-engine machine with a take-off weight of 200 tons (the prototype was 118 tons) with a triangular wing and a flight range of 6000 km. The aircraft was assembled in a single copy, which entered flight tests in the fall of 1959, and 10 years later added to the collection of the Museum in Monin. But the Tu-22 created at the same time with a take-off weight of about 100 tons was built serially, in the amount of more than 300 units.
Having accumulated some tangible experience in high-speed bombers by the early 60s, domestic aircraft manufacturers began working on a supersonic airliner. The starting point was the decision of the Soviet leadership to create the Tu-144. In the fall of 1962, the governments of France and great Britain reached an agreement on a joint program for the Concorde supersonic passenger airliner, which prompted the Soviet leadership to accept the proposal of Andrei Nikolaevich Tupolev for such a car.
Despite the comparable weight and size parameters and individual figures of flight characteristics of the M-50, Tu-22 and future Tu-144, the latter has made a significant step forward. Compared with previously created bombers, the value of aerodynamic quality (the ratio of lift to drag) was one and a half times higher. For the first time on a large aircraft (length about 66 m, wingspan-about 30 m), the so-called ogival wing (with a variable sweep angle in the span) was used. Note the huge relative fuel reserve: with a weight of 203 tons, the aircraft could take 95 tons of fuel.
The presence of a scientific and technical reserve allowed the Soviet Union to be a couple of months ahead of Europe, the first to lift a prototype of a supersonic passenger plane into the air. On December 31, 1968, test pilots Eduard elyan and Mikhail Kozlov flew around the Tu-144 No. 68001, and its counterpart in Toulouse took off from the ground only on March 2, 1969. Our plane was the first to break the sound barrier on June 5, 1969, and on may 25, 1970, at an altitude of 16,300 m, the car exceeded the speed of sound twice. Concorde caught up with her in five and a half months.
An improved pre-production car took to the skies in the summer of 1971, and in the spring of 1972, the first production Tu-144S assembled by the Voronezh aircraft factory (77102) took off. In December 1975, pilot operation began with cargo and mail on the Moscow-Alma-ATA highway with a length of 3,260 km. The flights were performed at supersonic speeds at altitudes of 16-18 km.
On October 29, 1977, the USSR air registry issued airworthiness certificate No. 03-144 for an aircraft with NK-144A engines, certifying that the Tu-144 was designed, built and tested in accordance with the "Temporary airworthiness standards for supersonic civil aircraft of the USSR" (VNLGSS). This allowed the Aeroflot crew under the command of Boris Kuznetsov to start passenger transportation on the Moscow-Alma-ATA route from November 1, 1977. They continued until may 1978. In total, a pair of Tu-144S made 55 flights with a total of 3,284 passengers. Including cargo, the number of Aeroflot flights was 102.
The problematic engines
The creation of the Tu-144 was a milestone in the development of the domestic aviation industry. However, the dream of Soviet leaders and aircraft designers to organize high-speed air traffic between the capital and the largest cities of Siberia and the Far East did not come true due to the imperfection of the power plant. Variant C of the aircraft with dual-circuit turbojet engines NK-144 due to increased fuel consumption instead of the estimated range of 6500 km showed only 3500 km (with a full cabin of 150 passengers when flying at an altitude of 18750 m, the figure was 3080 km). With such a kilometer, the speed advantages of a supersonic aircraft were not fully revealed.
Improvement of the Tu-144 was carried out both in the direction of aerodynamics (changing the twist of the wing and its area), and along the line of the power plant. Two design bureaus were involved in the work: Rybinsk Peter Alekseevich Kolesov and Samara Nikolai Dmitrievich Kuznetsov. The first had the experience of cooperation with the Sukhoi design Bureau and the experience gained during flight tests of the su-100 (T-4) bomber.
The Tu-160 is one of the most elegant aircraft of the Aerospace forces. For this, it is called the "white Swan". Photos from the site www.mil.ru
The machine was produced in a single copy and made its first flight on August 22, 1972 under the control of test pilot Vladimir Ilyushin. It was equipped with Rybinsk RD-36-41 engines with a thrust of 16 tons and with a take-off weight of 135 tons had a maximum flight range of 7000 km. During testing, an experimental vehicle with a remote flight control system accelerated to a speed corresponding to M = 1.7. However, in 1975 the theme was closed, and in 1982 the T-4 added to the collection of the Museum in Monin.
Based on the RD-36, Rybinsk specialists developed the RD-36-51A for an improved version of the Tu-144. Unlike the NK-144, it was originally designed for long-term supersonic flight without the use of afterburner. Due to this, fuel consumption for a given supersonic cruise flight mode decreased by 1.47 times. In total, 22 engines were assembled in 1969-1972, including for 200-hour bench tests. Upon their completion in 1978-1980, six improved models were assembled with a 15-stage compressor instead of a 14-stage one. Equipped with similar engines, the Tu-144D reached the range indicators (5-5. 5 thousand km with a typical load), close to those specified in the technical task. The aircraft from November 1975 to September 1979 performed flights from Moscow to Khabarovsk, delivering cargo and mail.
After passing the necessary checks, on June 9, 1981, the Tu-144D received the certificate of airworthiness No. 11B-144D according to the VNLGSS standards. The next step was to introduce improved Rybinsk engines (with the gas temperature increased from 1355 K to 1442 K), which allowed to increase the flight range of the aircraft with 150 passengers to 8000 km, with 200 passengers - to 6500 km. Tu-144D passenger flights were prepared, but did not take place. Closer to the beginning of the 80's, the country's leadership cooled to the idea of implementing supersonic air traffic in the Siberian expanses. Among the reasons – the disaster of 1973 and 1978, pretty dampened the reputation of an outstanding car.
Patience and hard work
Serial production was carried out at the Voronezh aircraft factory starting in 1967. In total, until 1984, 16 cars were assembled here, and four more remained in reserve. The total flight time for the Tu-144 fleet was 4110 hours in 2556 flights.
Preserved copies of the Tu-144 can be seen at exhibitions and museums in Zhukovsky, Kazan, Ulyanovsk and Monin. Aircraft number 10041, released in 1975 by the Moscow machine-building plant "Experience", added to the collection of the air force Museum on February 29, 1980. In the period from October 1975 to February 1980, it performed test flights, a total of 320 with a flight time of 582 hours and 38 minutes.
The Tu-144 program turned out to be a failure. However, it allowed us to accumulate experience and knowledge on the topic of supersonic aviation, as well as to create engines that were used on the next generations of long-range missile carriers. Here, the direction based on the original NC-144 came to the fore. Samara specialists under the leadership of Nikolai Kuznetsov consistently developed variants with indexes " A "(produced in 1973-1978) and" B"with additional compressor stages, which was reflected in a 22% reduction in cruising consumption in the standard mode, and a resource – from 50 to 300 hours ("A").
The development of this line continued in relation to power units for the Tu-22M (NK-144-22, NK-22, NK-23), Tu-22M3 (NK-25) and later Tu-160 (NK-32, produced since 1983) and Tu-160M2 (NK-32-02) bombers. The degree of pressure increase doubled, and the temperature of the gases increased by more than 20%. Thus, the Samara school of aviation engine building in the period from 1963 to the present has produced several generations of marching power plants for heavy-class supersonic aircraft.
When Russian-American relations were on the rise, one of the mothballed Tu-144s (flight 77114 with a flight time of less than 83 hours) was returned to flight condition and used as a flying laboratory. The Tu-144LL, equipped with NK-321 engines, completed several dozen flights in 1996-1998. The machine was used as part of a joint program with the United States to accumulate data and create a scientific and practical reserve in the interests of the HSCT (High-Speed Commercial Transport) and domestic supersonic passenger aircraft of the second generation.
Subsequently, this Russian-American program was criticized: they say, for little money, we voluntarily gave the Americans a lot of valuable information. However, we should not forget the state of the Russian military-industrial complex at that time. The topic of the Tu-144LL allowed Russian specialists to further advance on the topic of the power plant for supersonic aircraft of the future, to collect and process more data on semi-experimental NK-321 engines. The latter was a modification of the NK-32 and was characterized as a "multi-mode, dual-circuit, turbofan engine with a self-similar nozzle and a digital electronic control and surge protection system".
Director of the NC-32 program of UEC-Kuznetsov PJSC (part of rostec group») Sergey Kretov told NVO that the NK-32 02 series aircraft engine is an upgraded engine that recently passed flight tests as part of the Tu-160 production aircraft.
"In its production, modern technologies are implemented: new types of workpieces, methods of mechanical processing and hardening of parts. Modern control methods aimed at improving reliability are applied. Putting the engine into mass production was the impetus for modernization and technical re-equipment of the enterprise. The product is created in broad cooperation with the enterprises of JSC "UEC" with the use of modern principles of organization of production, – said Sergey Kretov.
Back on the warplane
Aviation is so arranged that it develops most rapidly when the civil and military directions support each other. The time came when the data taken from the Tu-144LL and its NK-321 were useful when creating the NK-32 engine of the second series, selected for the Tu-160M2 bomber.
And on November 3 of this year, the first plane with such engines took to the sky. The crew, led by test pilot Henri Naskidyants, spent 2 hours and 20 minutes in the air, reaching a maximum altitude of 6000 m. The necessary checks were performed on the updated General aircraft systems and avionics of the aircraft, and the operation of the NK-32-02 engines was evaluated. According to the report of the crew, the flight was conducted in normal mode, the systems and equipment worked without comments.
The experience accumulated by domestic engine builders and the scientific and production groundwork they have created should be used as widely as possible in the interests of our country. On the basis of the NK-32-02 Samara experts have proposed to create a ramless engine PD-30 in the class of 30 tons of thrust. It can be installed on the An-124 Ruslan instead of the standard d-18T engines designed and assembled in Ukraine. As well as a number of other promising aircraft developments for military transport and civil aviation.
Experience shows that the greatest success can be achieved by harmoniously developing military and civil aviation. The launch of the second series of the NK-32 series gives us another chance.
Vladimir Karnozov
Vladimir A. Karnozov-military analyst.