Operators of IL 96. Russian Aviation

Il-96 is a wide-body passenger aircraft, the creation of which began at the Ilyushin Design Bureau back in the late 70s of the last century. This aircraft became the first aircraft of this class developed in the Soviet Union. The Il-96 made its first flight in 1993.

Serial production of the Il-96 aircraft was launched at the Voronezh Aviation Plant; a total of 30 airbuses have been manufactured since its start.

Currently, the Il-96 is operated by the Special Flight Detachment "Russia", which includes the presidential flight. Since 1996, Russian leaders have been flying on the Il-96-300PU, a modification of the airliner created specifically for the head of state. In 2003, a new aircraft of this modification was built for Putin.

IL-96 is rightfully considered one of the most reliable passenger aircraft in your class. Since the start of operation, not a single accident has occurred with these machines that would have resulted in casualties. True, the total flight time of these aircraft is much lower than that of their foreign counterparts.

The Il-96 is also operated by the Cuban company Cubana. In 2014, Aeroflot wrote off the last six Il-96s, citing the high cost of operating them.

We can say that this plane was very unlucky, because the moment of its birth occurred during the period of the collapse of the country and economic crisis, when the domestic aviation industry was literally surviving and had no time to renew its aircraft fleet. At the end of the 90s, an attempt was made to modernize the aircraft, which resulted in the appearance of the Il-96-400 modification. However, it did not interest domestic air carriers too much; there were no orders for it from airlines.

Il-96 can be called one of the most famous and discussed domestic passenger aircraft. Interviews with high-ranking officials appear in the press with enviable frequency. Russian officials with promises of a speedy resumption of production of the Il-96 aircraft. But things are still there.

If speak about latest news associated with this aircraft, then at the beginning of this year, Deputy Prime Minister Rogozin visited the Voronezh aircraft plant and promised government support to aircraft manufacturers. According to the official, the Il-96-400 is quite capable of meeting the needs of domestic airlines for long-haul wide-body aircraft until the new Russian-Chinese airbus is ready.

Earlier, Industry Minister Manturov promised to allocate 50 billion rubles to resuscitate the production of Il-96. True, according to him, it is first necessary to solve the problem of excessive fuel “gluttony” of the machine, because according to this characteristic, the Il-96 cannot compete with the Boeing 767 and 777 or the Airbus 330 - its main competitors.

Despite all the difficulties of the early 90s, the new Il-96 had good prospects. At that time, foreign companies were seriously interested in the car. A modification of the Il-96M with Pratt&Whitney engines and advanced Western avionics was developed specifically for promotion abroad. In 1993, a prototype of this aircraft already flew, and soon it received Russian and American certificates. Why was this project never brought to fruition? And does he have a chance to take worthy place in the sky?

History of creation

Work on the creation of a Soviet wide-body passenger aircraft began in the first half of the 70s. At that time, most long-haul transportation in the Soviet Union and socialist countries was carried out on the Il-62 airliner. However, this aircraft, built in the early 60s, at that moment could no longer cope with the significantly increased passenger traffic. Due to its low capacity, the number of flights had to be increased, which created excessive pressure on airports. In addition, this aircraft was significantly inferior in terms of comfort to its Western counterparts.

A wide-body passenger aircraft is a machine with a fuselage diameter of 5-6 meters. These sizes allow you to place from 6 to 10 chairs in one row. It should be noted that the emergence of long-range wide-body passenger airliners almost immediately made narrow-body aircraft unprofitable. They had to be transferred to routes with low passenger traffic. An analysis carried out in the USSR in the mid-70s showed that within ten years Aeroflot would not be able to provide transportation on long-distance routes without a spacious wide-body aircraft.

At this time, in the OKB im. Ilyushin were developing a new large-capacity passenger aircraft, the Il-86. It was on the basis of this machine that it was decided to build a new long-range passenger aircraft. It received the name Il-86D. It differed little from the basic modification: only the wing area and the power plant, which consisted of more economical engines with a higher bypass ratio, increased. The idea of ​​​​creating two aircraft with a high degree of unification seriously reduced the development time of new aircraft, reduced their cost, and in the future should have significantly simplified maintenance.

However, the IL-86D was never realized in metal. At the end of the 70s, on its basis it was decided to create a new long-range passenger aircraft - the Il-96 aircraft. Changes were made to the design of this machine, which significantly increased its technical excellence.

At the turn of the 70s and 80s, aviation technology developed so rapidly that after completing work on the Il-96, the designers had to take up the work again and create a fundamentally new project, because the aircraft they created was already seriously at the start of its career. lagged behind Western counterparts. The new promising airliner received the name Il-96-300, and during its development the components and assemblies of the Il-86 airliner were no longer used.

The first takeoff of the Il-96-300 took place in September 1988, testing continued until the end of 1992, after which the airliner was certified. In 1989, the aircraft was demonstrated at the Le Bourget air show. If we talk about flight performance new car, then it can be noted that the designers managed to reach new level, compared to aircraft created at the Design Bureau named after. Ilyushin earlier. For example, the fuel consumption of the Il-96-300 per passenger kilometer was two times lower than that of the long-haul Il-62.

For the work on the creation of a new aircraft, the OKB team named after. Ilyushin was awarded the State Prize.

The first Il-96-30s were transferred to the Domodedovo air squad, and commercial operation of the airbus began in 1993. Initially, the airliners were mainly used for flights on international routes.

A serious blow to further development the IL-96 project was the decision of the Russian government to remove duties on the import of foreign high-capacity aircraft into the country. Aeroflot openly lobbied for him, promising to purchase a large batch of Il-96 if duties were reduced. The decision was made, but the purchase of domestic aircraft never took place.

In 2000, a new modification of the airliner was developed - Il-96-400, which had a larger passenger capacity and an increased flight range. However, domestic air carriers were not interested in this aircraft; only a few Il-96-400Ts, the transport version of this aircraft, were purchased.

In the mid-2000s, three Il-96-300s were sold to Cuba, and one of them was made in the “presidential” version. Now not only Putin flies on the Il-96, but also the top management of Freedom Island.

Over the years, negotiations on the supply of the aircraft were conducted with China, Syria, Iran, Peru and even Zimbabwe. They were not particularly successful.

In 2009, the government announced the need to phase out the Il-96-300, allegedly due to the fact that it cannot compete on equal terms with the latest European and American analogues.

In 2014, Aeroflot decommissioned all of the company's Il-96 aircraft.

However, already next year, the Ilyushin Aviation Complex OJSC announced plans for the next modernization of the Il-96 and the resumption of its serial production. Next year, representatives of the enterprise reported that they were improving the fuel efficiency of the airliner and planned to bring it to the level of modern Western analogues. CEO The Voronezh Aviation Plant reported that the Il-96-400M will be ready by 2019. And the government has already promised to allocate funds for this project.

In February of this year, a message appeared in the media that a firm contract had been signed between the manufacturer and UAC to carry out design work on the Il-96-400M. The aircraft prototype is scheduled for production in 2019.

Description of design

Il-96-300 is a cantilever wide-body low-wing aircraft with four engines, vertical tail and swept wings.

The fuselage of the aircraft has a diameter of 6.08 meters; depending on the layout of the passenger cabin, it can accommodate from 235 to 300 passengers. With a standard layout (300 seats), the passenger cabin is divided into two salons, with 66 seats in the front cabin and 234 seats in the rear cabin. They are arranged in a row of nine seats with a pitch of 870 mm and two aisles of 550 mm. Aircraft with a passenger capacity of 235 people have a passenger cabin divided into three cabins: first class (22 seats with a distance between rows of 1020 mm), business class (40 seats) and economy class (173 seats). The IL-96 cabin is in no way inferior to the best foreign analogues in terms of comfort for passengers.

The lower deck of the Il-96-300 is occupied by cargo compartments. There are three of them, the first two can accept nine standard ABK-1.5 aviation containers, and the third is intended for the transportation of piece cargo.

The IL-96 has a wing with a span of more than 60 m and an area of ​​391 m2 with large vertical tips at the edges. In area it significantly (by 70 m2) exceeds the wing of the Il-86 and is equipped with complex mechanization. It consists of slats that occupy the entire length of the leading edge and double-slotted flaps.

The vertical tail of the aircraft is also significant; it is one and a half meters higher than that of the Il-86. This feature of the airliner allows it to maintain stability in flight even if one of the engines fails.

The IL-96 has four landing gear: three main ones, located under the center section, and a nose gear. Each of the main struts has a four-wheel trolley with brake wheels, and the front strut has two non-brake wheels. The size of all aircraft landing gear wheels is the same.

The power plant of the airliner consists of four PS-90A turbofan engines with a high bypass ratio, which can create a thrust of 16 thousand kgf. They are installed in pylons that are attached to the wing consoles. PS-90A is made according to a two-shaft design, there is a reverse. The engine is equipped with a four-stage low-pressure turbine and a two-stage high-pressure turbine. PS-90A is distinguished by a modular design, which facilitates its maintenance: if necessary, one or another module - out of eleven available - can be quickly replaced.

For the first time in the history of Soviet aircraft construction, the aircraft's power plant was equipped with an electronic control and monitoring system "Diagnoz-90", which had two channels. This system automatically monitors fuel consumption and protects engines from surge. They plan to equip the promising Il-96-400M with a new PD-35 engine, which is currently being developed.

The Il-96-300 was equipped with the latest (for its time, of course) flight and navigation system, which made it possible to abandon the navigator and make do with a crew of three people. The IL-96-300 is the first Soviet aircraft to be equipped with the VSUP-85-4 electronic flight control system - in addition to traditional analog instruments, electronic indicators also appeared in the IL-96-300 cockpit. This aircraft is equipped with an EMDS system.

The Airbus fuel system is in many ways reminiscent of a similar system in the Il-86. The fuel is located in nine caisson tanks, from where it is pumped into the pre-consumption tank and, further, into the supply compartment, which each engine has. Four tanks are located in the wing consoles, another is located in the center section.

Il-96-300 is equipped with an automatic air conditioning system. Air is supplied to the cabin from the engines.

The aircraft is equipped with an electric pulse anti-icing system. The air intakes are heated by air supplied from the compressor chamber.

Modifications

Since the start of mass production of the Il-96 aircraft, several modifications of the aircraft have been developed. Below are the main ones:

• IL-96-300. Basic modification, equipped with four PS-90A engines. The airliner first took to the skies in September 1988 and entered service with Aeroflot in 1993. A total of twenty aircraft of this modification were produced; in 2009, it was decided to withdraw it from production. This machine has a maximum flight range of 13.5 thousand km, it can carry up to 300 passengers;
• Il-96-300PU/PU(M1). “Presidential” modification of the airliner, which was specially developed on the basis of the Il-96-300 for transporting the country's top officials. A total of five aircraft of this modification were built. The letters “PU” in the designation of the machine mean “control point”. In terms of its characteristics, it practically does not differ from the basic version of the aircraft; the flight range of the aircraft is slightly increased. In essence, the Il-96-300PU is an air command post that allows you to control the country and the armed forces during a nuclear conflict. Externally, this airliner is practically no different from a regular production aircraft. This machine was manufactured in 1995 for the first Russian President Boris Yeltsin. The second Il-96-300PU was created for Vladimir Putin; it first flew in 2003. The last aircraft of this modification was manufactured at the end of 2019;
• IL-96-400. A modification of the aircraft that was developed in 2000. The vehicle has a longer fuselage compared to the Il-96-300, it is equipped with PS-90A-1 engines (17.4 thousand kgf thrust) and more advanced avionics. This liner can accommodate 435 passengers;
• IL-96-400T. Transport version of the Il-96-400 airliner. The first aircraft was assembled in 2007; a total of four aircraft were produced. In 2014, it was decided to convert one of the Il-96-400Ts into an air control center for the needs of the FSB of the Russian Federation. In 2019 Russian Ministry Defense announced the purchase of two aircraft in the tanker modification. If the operation of these aircraft is successful, then the military department is ready to order 30 more aircraft;
• IL-96-400TZ. This is a tanker aircraft based on the Il-96-400T. It will be capable of transmitting 65 tons of fuel over a distance of 3.5 thousand km;
• IL-96VKP. This modification of the airliner is a strategic air command center. Currently, Ilyushenites are working on its creation; in the future, this aircraft will replace the Il-86VKP;
• Il-96M. Modification of the base model Il-96-300 with an extended fuselage, Pratt&Whitney engines and Western avionics. The prototype of this aircraft first took off in April 1993 and was later repeatedly demonstrated at various air shows. In 2009, cut into scrap;
• IL-96MD. Modification of the aircraft, equipped with Pratt & Whitney PW4082 engines;
• IL-96MK. Modification with four NK-92 engines.

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IL-96- a wide-body passenger aircraft for medium and long-haul airlines, designed at the Ilyushin Design Bureau in the late 1980s. It made its first flight in 1988 and has been in serial production since 1993 at the Voronezh Joint-Stock Aircraft Manufacturing Company plant. Il-96 became the first and last Soviet long-range wide-body aircraft.

By the mid-1970s, almost all long-haul air transportation in the USSR and socialist countries was carried out on Il-62 aircraft. However, the capabilities of these aircraft could not fully respond to the rapid growth in the volume of long-distance transportation: due to the relatively low passenger capacity, the number of flights increased, and accordingly, the load on airports increased.

In addition, the cabin of the narrow-body aircraft was far from the degree of comfort that was achieved on the Boeing 747, which entered service in 1969, which became the world's first wide-body aircraft.

In 1978, using the results of work on the Il-86D project, the OKB began developing the Il-96 aircraft with a T-shaped tail, a higher aspect ratio wing with supercritical nose profiles and an area of ​​up to 387 sq.m. Research on this option was carried out until 1983, when the progress achieved in the field of aviation science and technology made it possible to abandon the idea of ​​​​creating Il-96 aircraft using in its design many ready-made units and systems of the Il-86 aircraft and move on to the creation of a fundamentally new Il-96-300 aircraft.

The Il-96-300 aircraft differs from its predecessor Il-86 by having a fuselage shortened by 5.5 meters, a larger wing span and a reduced sweep angle, increased dimensions of the vertical tail, and an improved interior of the passenger cabin.

New alloys are used in its design and the proportion of composite materials is increased. The aircraft uses an automatic fuel consumption control system, which allows it to maintain the alignment of the aircraft in flight. Particular attention was paid to the reliability and safety of aircraft operation.

The Il-96 uses a Russian digital avionics system with six color multifunction displays, an electronic thrust control system, an inertial navigation system and satellite navigation aids. Also on Il–96–300 it was decided to install new Solovyov PS-90A engines. The PS-90A smooth nacelle, uncharacteristic of the dual-circuit engines previously produced in the USSR, increased the fuel efficiency of the aircraft.

A set of requirements presented to Ilyushin Design Bureau by the Ministry civil aviation- transportation of a commercial load of 30 and 15 tons over a practical range of 9,000 and 11,000 km with a cruising speed of 850 to 900 km/h at an altitude of 9,000 to 12,000 m - made the traditional one the optimal aerodynamic design: a four-engine cantilever low-wing aircraft with a vertical tail. The T-shaped tail was abandoned. The IL-96-300 was initially created as an aircraft with development potential: its design allows for the relatively fast and inexpensive development of various modifications of the aircraft.

Further development of the aircraft Il–96–300 was the creation of the Il-96M variant, in which many US aviation companies took part. The fuselage of the aircraft was extended to 64 meters, that is, even more than on the Il-86. But the main distinguishing feature of the Il-96M was the Pratt & Whitney PW2337 engines.

The prototype was created on the basis of the first prototype Il-96-300. The plane took off on April 6, 1993, but was not put into serial production. On the basis of the Il-96M, the cargo Il-96T was created, which was also assembled in a single copy. A double-deck version of the Il-96-550, equipped with an NK-92 turbofan engine (4 x 20,000 kgf) and designed to carry 550 passengers, was also studied.

In 1999–2000, work was carried out on the project of the Il-96-400T cargo aircraft, which has the capabilities of the Il-96T cargo aircraft, but has Russian PS-90A-2 turbofan engines and on-board equipment. It made its first flight on May 16, 1997. In operation since 2009.

The first prototype was assembled directly at the design bureau workshop on Leningradsky Prospekt in Moscow. At the beginning of September 1988, the plane was solemnly rolled out of the assembly shop. The first flight of the experimental Il-96-300 aircraft was carried out on September 28 from the Frunze Central Airfield on Khodynskoye Field. The plane was piloted by a crew under the command of Stanislav Bliznyuk, Honored Test Pilot of the USSR, Hero of the Soviet Union. Flying right over central regions Moscow lasted 40 minutes.

During testing IL-96 performed several notable long-range flights, including Moscow–Petropavlovsk–Kamchatsky–Moscow without landing in Petropavlovsk. The plane covered 14,800 km in 18 hours and 9 minutes. On June 9, 1992, Il-96 flew from Moscow to Portland via the North Pole, spending 15 hours in the air.

The aircraft was tested in Yakutsk at –50 °C and in Tashkent at +40 °C. Based on the test results, on December 29, 1992, the aircraft was awarded an airworthiness certificate. For six months, the new cars were tested on Aeroflot routes, and due to lack of funding, operational tests had to be combined with commercial cargo transportation.

Commercial operation of the aircraft began on July 14, 1993 on the Moscow–New York route. At first, the aircraft was used mainly on foreign flights: to Singapore, Las Palmas, New York, Tel Aviv, Palma de Mallorca, Tokyo, Bangkok, Los Angeles, San Francisco, Seattle, Rio de Janeiro, Buenos Aires, Seoul, Sao Paulo, Havana, Hanoi, Santiago, Lima.

Everyone flying on this moment at Aeroflot Il-96 aircraft were collected in the first half of the 1990s. In exchange for reducing duties on the import of foreign equipment, Aeroflot undertook to purchase an additional batch of Il-96, but the deal never took place, although duties were reduced.

In 2005–2006, three Il-96-300s were delivered to Cuba, including one to serve the President of Cuba. In 2009, the Venezuelan government signed a contract for the supply of two Il-96-300 - one for passenger, the other for VIP transportation. In the fall of 2008, the IFC leasing corporation seized two Il-96-300s from Krasnoyarsk Airlines due to the company's insolvency.

In 2009, Polet Airlines began operating cargo planes Il-96-400T, which Aeroflot initially planned to buy, but later abandoned them. As of September 2009, Polet airline has three Il-96-400T aircraft with a plan to receive three more aircraft in 2010.

Also, during the MAKS-2009 aerospace salon, an agreement was signed with a Peruvian airline for the supply of two Il-96-400T freighters with an option for another such aircraft, and negotiations are underway on its delivery to China and the countries of the Middle East. The current version of the aircraft is equipped with new engines and the most modern Russian-made flight and navigation system, which allows the aircraft to be operated without any restrictions around the world.

Such aircraft have not yet been produced in Russia. Il-96-400T can transport up to 92 tons of cargo on medium and long-distance routes. The aircraft is certified in accordance with Russian airworthiness standards, harmonized with the standards of the European Union and the USA. At various times, negotiations were held on the sale of Il-96 to China (three aircraft), Syria (three aircraft) and even Zimbabwe. KrasAir airline planned to transfer two of its Il-96s to Iran Air on a one-year wet lease in 2007.

The first two prototypes (nos. 96000 and 96001), stored for a long time at the Gromov Flight Research Institute in Ramenskoye, were destroyed in May 2009. Another 5 aircraft (2 KrasAir and 3 Domodedovo Airlines) are temporarily taken out of service and are in storage.

Creators Il–96–300 were guided by the economic indicators of the Boeing 767, however, since the first flight of the Il-96-300, long-haul airliners of the new generation Boeing 777, Airbus A330, Airbus A340, Airbus A380 have been put into operation, and the Boeing 787 and Airbus A350 are expected to enter the market soon. By 2012, two more Il-96-300 will be produced for the SLO Russia (including the presidential Il-96-300PU). The cargo version of the Il-96-400T aircraft remains in production.

Flight characteristics of Il-96

At first I wanted to give the article as a separate material, but then I thought that it would be better to put such information together.

MS-21 - airliner with a “black” wing

In global civil aviation there are only three aircraft whose wings are made of polymer composite materials (PCM). These are the Boeing B787 Dreamliner, Airbus A350 XWB and Bombardier CSeries. More recently, the Russian MS-21 joined this trio.

One of the advantages of composite parts is their resistance to corrosion and damage propagation. Composites can be called universal materials; they can be used in aircraft construction, the defense industry, shipbuilding and other areas in which increased demands are placed on the material for such characteristics as strength and rigidity, good resistance to brittle fracture, heat resistance, stability of properties during sudden changes in temperature, durability .

The production of composite parts in the aircraft industry is carried out by autoclave molding - producing multilayer products from so-called prepregs - semi-finished composite materials obtained by preliminary impregnation of carbon fabrics with polymer resin. One of the significant disadvantages of this technology is the high cost of the resulting parts, which is largely determined by the duration of the molding process, the limited shelf life of prepregs and the high cost of technological equipment. According to regulatory documents, the guaranteed shelf life of prepreg in a freezer in the temperature range from -19°C to -17°C is 12 months. The storage time of the prepreg at a temperature of 20±2°C is 20 days, while the blank part can be laid out in the conditions of the production site only for 10 days.

An alternative to prepreg-autoclave technology are “direct” processes, the essence of which is to combine the operations of impregnating carbon fiber or glass fabric with a binder and molding the part, which leads to a reduction in production cycle time, reduced energy and labor costs and, as a result, a reduction in cost technologies. One of these processes is the vacuum infusion method - Vacuum Infusion, VARTM.

According to this technology, the impregnation of dry carbon fiber and the molding of the part occurs on a tool with a vacuum bag attached to it. The polymer binder is pumped into the mold due to the vacuum created under the vacuum bag. This allows you to significantly reduce the cost of preparing for the production of large structures due to the possibility of using simpler and cheaper equipment. The main disadvantages of vacuum infusion technology include, first of all, the difficulties of reproducibility of the process - careful development of the technology is necessary in order to obtain parts with stable geometric and physical-mechanical characteristics.

As a result of a survey conducted in the United States in 2006, American aerospace manufacturers concluded that the vacuum infusion method was not sufficiently researched and developed for use in the manufacture of large tier 1 parts in passenger airliners.

But a lot has changed since then.

As is known, the wide-body Boeing B787 Dreamliner has a fuselage and wings made of PCM, which are produced using the autoclave-prepreg method. Also for this aircraft, the German company Premium Aerotec uses the VAP (Vacuum Assisted Process) method to manufacture the pressurized bulkhead, Boeing Aerostructures (formerly Hawker de Havilland) uses the CAPRI (Controlled Atmospheric Pressure Resin Infusion) method to produce deflectable aerodynamic elements of the fin, wing and tail: ailerons, flaperons, flaps and spoilers. The Canadian company Bombardier uses the LRI method and autoclave polymerization to produce the wings of the CSeries family of aircraft. GKN Aerospace from the UK in May 2016 demonstrated a composite center section manufactured using a non-autoclave vacuum infusion method using an inexpensive set of tools and equipment.

The Russian Aerocomposite plant in Ulyanovsk is the first in world civil aviation to use the non-autoclave vacuum infusion method (VARTM) for the manufacture of large first-level integrated structures from PCM.

The wings and empennage of a typical narrow-body aircraft make up 45% of the airframe's weight, with the fuselage accounting for another 42%. UAC sees a problem that must be solved in order to achieve success in the conditions of fierce competition in the market of narrow-body aircraft - if the optimal use of composites in the design of the MC-21 will reduce the weight of the airliner and reduce production costs by 45%, then both the aircraft and Russian technological companies will strengthen their positions in the global aircraft industry.

Why vacuum infusion?

A 2009 study found that using an oven instead of an autoclave can reduce capital costs from $2 million to $500,000. For parts between 8 m² and 130 m², an oven can cost 1/7 to 1/10 the cost of a comparable sized autoclave. In addition, the cost of dry fiber and liquid composite core can be up to 70% less than the same materials in prepreg. The MS-21 has a wing size of 3x36 meters for the 200 and 300 models, and 3x37 meters for the MS-21-400 model. The size of the center section is 3x10 meters. Thus, the cost savings of Aerocomposite seem to be very significant.

However, Anatoly Gaidansky, General Director of Aerocomposite CJSC, explains that the cost of autoclaves and prepregs was not the only decision criterion in favor of the vacuum infusion method. This technology makes it possible to create large integral structures that work as a single unit.

At the request of JSC Aerocomposite, the Austrian companies Diamond Aircraft and Fischer Advanced Composite Components (FACC AG) manufactured 4 ten-meter prototypes of the wing caisson, which from the summer of 2011 to March 2014 underwent a full range of strength tests at TsAGI, and an experimental joining of the prototype caisson was carried out wing with center section. These studies, firstly, confirmed that the design parameters laid down by the designers ensure flight safety, and secondly, the use of large integral structures significantly reduces the labor intensity of assembly, reduces the number of parts and fasteners.

Anatoly Gaidansky adds to this: “Dry carbon fiber can be stored almost indefinitely, which is impossible with prepregs. Infusion allows us to provide adaptive production planning based on program scale.”

Currently, the vacuum infusion method is planned to be used for the manufacture of large power integral elements of the first level: spars and wing skin with stringers, sections of center section panels, power elements and skin of the keel and tail. These elements will be manufactured and assembled at the Aerocomposite plant in Ulyanovsk.

Prepregs and autoclave molding technology will be used at KAPO-Composite in Kazan, a joint venture of Aerocomposite CJSC and the Austrian FACC AG. Fairings, wing mechanization elements will be produced here: ailerons, spoilers, flaps, as well as elevators and rudder.

Autoclaves at the KAPO-Composite plant in Kazan / Photo (c) Aerocomposite JSC

Technology development

The technology for producing the “black” wing of the MS-21 aircraft was created by AeroComposite specialists in close cooperation with foreign manufacturers of technological equipment. The vacuum infusion method has existed for many years, but such a large and complex product as an airplane wing was first made using this technology in Ulyanovsk.

No one has ever used automatic laying out of dry material for the manufacture of large integral structures in the aircraft industry.

From 2009 to 2012, Aerocomposite worked with various companies worldwide to select materials and repeatable process technology of the required precision and quality. Resins, dry carbon fiber and prepregs from American companies Hexcel and Cytec were selected. Robotic installations for dry automated laying of carbon filler were supplied by Coriolis Composites; wing spars are produced using this equipment. The robotic installation for dry laying of the portal type, on which the wing panels are made, was supplied by the Spanish MTorres. TIAC thermal infusion centers were developed by the French company Stevik.

According to Anatoly Gaidansky, the vacuum infusion process itself does not impose special requirements on the design of structural elements of the wing, it mainly affects the development of technological equipment, where a balance must be maintained between the ability to produce parts with high precision, while maintaining the functionality of the infusion process . In the research laboratory of JSC Aerocomposite, a large number of tests were carried out with materials, parts and samples of elements to determine this balance. As a result, a fabric was chosen in which the carbon fiber was not intertwined, but was fastened into a single fabric using a polymer thread. Due to the fact that the fiber does not intertwine, it has virtually no mechanical damage that affects the strength of the part.

“We tested open-textured materials to see how the resin flows, as well as denser fibers that require different filler permeability measures, such as tape gaps,” says Gaidansky.

MTorres was a key player in the material selection process as the Spanish company experimented extensively with different options for machine laying of dry fibre. Despite the fact that she already had significant experience, gained in 2009 with the development of fiberglass blades for Gamesa wind turbines, in 2012 a contract was signed with Aerocomposite to develop equipment for the automated laying of dry carbon fiber, which seemed to be a much more difficult task. . Composite products usually consist of several layers of carbon fiber with different orientation angles - such fabric laying is necessary to optimize resistance to load in various directions, since a composite wing during aircraft operation is exposed to a complex external load, which works in both compression and tension, and for twisting.

“Dry material, unlike prepregs, by definition is not impregnated with any resin, and thus easily moves from the position in which it was laid,” explains MTorres sales director Juan Solano. “Our goal was to somehow fix the material for accurate automated laying and make sure that it does not change its position later.”

To solve this problem, a very thin layer of thermoplastic was used as a bonding element to hold the fiber in place. Mr. Solano says that to activate the bond layer, MTorres developed a heat sink that is placed at the head of the preform to ensure minimal sticking. This solution made the automated layout process viable.

When choosing carbon fiber and composite resin, the goal was to standardize as much as possible the materials that will be used for the manufacture of both the wing and the center section panels. Hexcel's HiTape has been modified to meet MTorres specifications to enable automated lay-up and fiber alignment accuracy. Hexcel claims that with HiTape it is possible to achieve automated layup speeds of 50kg/hour. However, Anatoly Gaidansky clarifies: “At the moment, for the very beginning of our program, we are targeting a layout speed of 5 kg/h. However, in the future we will improve the technology to improve the productivity of complex structures. Relevant studies are currently underway in our laboratory.”

Manual cutting of carbon fiber in the research laboratory of Aerocomposite JSC

After fiber placement, the preform is placed in a TIAC thermal infusion unit. TIAC is an integrated system that consists of an injection module, a heating module and a hardware and software complex to ensure automation of the infusion process with precise adherence to specified process parameters. The unit mixes, heats and degasses the epoxy resin, controls the process of filling the vacuum bag with resin and the polymerization process. TIAC monitors and controls the temperature and amount of resin entering the preform, filling speed, vacuum bag and preform integrity. The vacuum level is controlled with an accuracy not exceeding 1/1000 bar - 1 millibar.

Automated thermal infusion center TIAC 22×6 meters

Spar in the thermal infusion center

Center section panel in thermal infusion center

The production cycle time varies from 5 to 30 hours depending on the type, size and complexity of the part being manufactured. The polymerization process takes place at a temperature of 180°C and can be maintained with an accuracy of ±2°C up to a maximum value of 270°C.

How it happens in reality

The technological process for manufacturing the MS-21 wing box is as follows:

1. Preparing equipment and laying out auxiliary materials.
2. Laying out dry carbon tape and pre-forming in automatic mode on lay-out equipment.
3. Assembling the vacuum bag.
4. Infusion (impregnation) of a dry workpiece in a thermal infusion automated center.
5. Disassembling the package and cleaning the parts.
6. Carrying out non-destructive testing.
7. Machining and geometry control.
8. Painting and assembly.

All work is carried out in a “clean room”, in which the number of dispersive particles in the air does not exceed the number in a sterile operating room, because if even a small speck of dust gets into the carbon, it becomes of poor quality and the product will be rejected.

After laying out the spar preforms, they go to the section for moving from positive to negative equipment, and the wing panel skin preforms go to the section for moving the laying out equipment to the infusion one. Here the equipment is sealed in a special envelope, with tubes connected to it from different sides. Air is pumped out one at a time, and binder is supplied through others due to the resulting vacuum.

The stringers and panels are laid out of carbon fiber separately, but using special equipment they are filled with composite resin together. Polymerization of the panel with stringers using infusion technology occurs in one cycle. With autoclave technology, two curing cycles are required: 1st cycle – curing of stringers, 2nd cycle – joint curing of stringers and sheathing, while the total time costs are 5% higher, and energy costs are 30% higher than when using VARTM technology .

The vacuum infusion method in one impregnation cycle makes it possible to create an integral monolithic part, as opposed to adhesive-riveted autoclave structures, where an adhesive film is placed between the stringer and the skin, and the process of installing mechanical fasteners for additional fixation of the stringers increases the complexity of manufacturing panels by up to 8%.

Next, the preforms are moved to automated thermoinfusion centers with working area dimensions of 22x6x4 m and 6x5.5x3 m, depending on the size of the part. Here the process of infusion and polymerization of the product takes place.

The assembly line stand, where the final joining of wing panels of the MC-21 aircraft will be carried out

At the end of the infusion, the part enters the non-destructive ultrasonic testing area. Here, using the Technatom robotic installation, the quality and reliability of the resulting part is assessed - the absence of cracks, cavities, unevenness of the hardened filler, etc. Non-destructive testing is of particular importance when creating and operating vital products, which, in particular, is an aircraft wing.

The next stage is mechanical processing of the part on a 5-axis milling center MTorres, after which the finished panel or spar is delivered to the wing box assembly area.

What does a composite wing provide?

Air flow around a wing of finite span - the appearance of inductive drag

As a result, two vortex ropes are formed behind the ends of the wing, which are called co-current jets. The energy spent on the formation of these vortices determines the induced drag of the wing. To overcome inductive resistance, additional engine energy is consumed, and, consequently, additional fuel.

There is no induced drag on a wing of infinite aspect ratio, but a real airplane cannot have such a wing. To assess the aerodynamic perfection of a wing, there is the concept of “aerodynamic quality of the wing” - the higher it is, the more perfect the aircraft. The aerodynamic quality of a wing can be improved by increasing its effective aspect ratio - the longer the wing, the lower its induced drag, lower fuel consumption, and greater flight range.

Aircraft designers have always strived to increase the effective aspect ratio of a wing. For the MS-21 wing, a supercritical profile was chosen - a profile in which the upper surface is almost flat and the lower surface is convex. One of the advantages of this profile is the ability to create a high aspect ratio wing, and in addition, such a wing makes it possible to increase cruising flight speed without increasing drag. The laws of aerodynamics force swept wings to be made thin; a supercritical wing can be made thick without increasing aerodynamic drag. The design of such a wing is lighter and more technologically advanced to manufacture than a thin one, and the resulting internal space can accommodate a larger supply of fuel.

The typical wing aspect ratio for aircraft of previous generations was 8–9, for modern ones it was 10–10.5, and for the MC-21 it was 11.5. To make a wing from aluminum with a high aspect ratio, in order to maintain its rigidity, it would be necessary to significantly increase the thickness of the wing, because aluminum is a soft metal, and increasing the thickness of the wing means increasing drag. Carbon fiber is a much more rigid material, therefore, even without the use of winglets, the high aspect ratio composite wing of the MS-21, formed by thin supercritical profiles (almost flat upper and convex lower surfaces), allows for cruising speeds flight to obtain an aerodynamic quality that is 5-6% better than that of the latest foreign analogues, and thereby achieve a longer flight range with less fuel consumption, which ultimately increases the economic efficiency of the airliner and its competitive advantage

Right composite wing of MS-21

Laying out the lower panel of the future wing of the MS-21 aircraft at the AeroComposite-Ulyanovsk plant

There has never been anything like this in our aviation industry. To be honest, I have never seen anything like this on Boeing or Airbus. And being at the plant, where all the employees are in white coats and shoe covers, there are special requirements for air quality and you see your reflection in the flooring, you can’t believe that all this is in Russia. For the first time in recent history, we are not trying to replicate old proven technologies, and we are not trying to blindly copy foreign experience, but are innovators and want to be at the technological forefront of the global civil aircraft industry.

Conclusion

The overwhelming superiority of the Western aviation industry in technology, technical equipment, the level of properties of the structural materials used, the efficiency of approaches to organizing design and production processes provides American and European civil aircraft with competitive qualities that are up to today could not be implemented in products of the domestic aviation industry. Such promising projects as the MS-21, designed to become the “locomotives” of the comprehensive modernization of the Russian civil aircraft industry, should change the current situation. Already in the process of carrying out experimental work at the stage of detailed design, the participants of the MS-21 Program created the groundwork for the formation of modern production, focused on the most advanced technologies.

September 29, 2016 at the Center international trade The awards ceremony for the winners and laureates of the Aircraft Builder of the Year competition took place. Members of the Expert Council reviewed over 100 works of enterprises, organizations and creative teams. The results of the competition were summed up at a meeting of the Organizing Committee on September 5, 2016. The winner of the nomination “For the creation of new technology” was the competence center of the United Aircraft Corporation - the AeroComposite company for the development and application of the vacuum infusion method in the creation composite wing new passenger plane MS-21-300. General Director of AeroComposite JSC Anatoly Gaidansky, in turn, thanked the team, partners and everyone who worked together for seven years to implement this project.

An-124 "Ruslan" - strategic military transport aircraft

InoSMI - Science

Wikipedia

Photo (c) UAC/Aviastar-SP/Irkut Corporation http://aviation21.ru/ms-21-lajner-s-chyornym-krylom/

Andrey Velichko,
August 2016

We can imagine the president's working day Russian Federation. As we know, he is forced to travel throughout to the globe. The week is scheduled hour by hour: today he needs to go to America, in a few days to Australia, and he also solves numerous problems in the Russian Federation. It turns out that the fastest way to travel is by plane. Air Force One serves for Putin not only as a means of transportation, but also as a mobile control center for a huge state and at the same time an “office in the air.”

Since the beginning of the Great Patriotic War, high-ranking officials have been using airplanes as a means of transportation. A special aviation group was created. It provided aircraft and controlled the state of the “aerial residence” of the head of state.

Joseph Vissarionovich Stalin used the S-47 aircraft for his work (this is a copy of the Li-2). During the flight, he was accompanied by twenty-seven Red Army Air Force fighters.

Nikita Sergeevich Khrushchev made business trips mainly on the Il-18. He loved to travel. What the world remembers most is the trip to the United States of America in 1959. Then, for the flight, the Secretary General chose a Tu-114 aircraft, this is the largest aircraft in the world. He did not fly alone, but with his family and 63 accompanying persons.

The guests who arrived in America could not immediately and normally descend to the ground, since the air base did not have a ladder long enough to reach the doors of the tall Tu-114. A fire truck with a huge ladder was needed to receive Russian guests. Soon, aircraft designers created the Il-62 especially for him; it was Leonid Ilyich Brezhnev’s favorite plane; Yuri Vladimirovich Andropov, Konstantin Ustinovich Chernenko and Mikhail Sergeevich Gorbachev also flew it on their work trips. During its entire operation, the aircraft has never let its VIP passengers down.

Putin's aircraft fleet

What planes does Vladimir Vladimirovich Putin fly on? The aircraft fleet of the Russian head of state consists of 8 airplanes and 2 helicopters. He mainly uses the flagship Il 96-300PU (“control point”) for flights. This is a very large aircraft, it has everything you need for efficient work and good rest.

This aircraft is equipped with a complete set of electrical equipment. This is an excellent platform for managing the country and the army of our state. The Il-96-300 PU has all the appropriate means of communication, not excluding satellite ones, so it is impossible to hack the control system of the presidential aircraft.

The main advantage is that absolutely no one has any idea which route the presidential plane will take.

• And he can also choose any other equipment for air travel, for example, the following brands of aircraft:
• TU-154M;
• TU-134;
• IL-62M;
• YAK-40;
• Il-96-300 (main);

IL-62 (reserve).

To be on the safe side, Air Force One always has another plane accompanying the head of state, this is what all presidents do. And Putin chooses the plane that will meet the conditions, the nature of the trip, and the flight distance. For example, for India one brand of aircraft is used, but for Yakutia a completely different one is needed.

Putin usually uses planes designed specifically for presidential flights on working visits, but it has also happened that he had to fly in a fighter jet.

Or when you need to transfer to a helicopter, this is the Mi-8. The aircraft must carry a commander and two changes of crew, and is also served by a flight attendant of five men and five women.

In 2012, the Rossiya flight squad received another addition, another Il-96-300 with tail number RA96020, and in 2013 another one, which was ordered with tail number RA96021. Presidential plane Press employees are always interested in not only what aircraft the flight is on

Russian President

(by the way, photos of the presidential Il-96 are constantly published on the pages of the Russian press), but also how to get exactly such a job, but there is naturally a tough selection process.

The commission selects for work in the State Customs Committee "Russia": according to age, level of qualifications, the candidate must be responsible, diligent, trustworthy, and disciplined. Newcomers, as a rule, do not get on board number 1; first they need to go through all the steps of the career ladder and achieve the highest level of professionalism. This presidential plane is operated by Rossiya Airlines.

The rich decoration of the aircraft is not a toy for personal use, not for showing off; guests from abroad, diplomatic meetings, and authorized media representatives are often on this board.

The plane of the head of state is a special symbol; it creates a special reputation of the Russian Federation for foreign guests. There are no “gold toilets”; the decoration of the rooms is in the “sovereign” style. Nobility, beauty, quality, comfort, without unnecessary “tinsel”, vulgarity and flashy luxury.

The Presidential Board is a comfortable flying office for business trips around the world, it is not expensive toy like the eastern princes, who have swimming pools and concert halls with an orchestra. And the high cost of Air Force One is most associated with secret electronic equipment and the provision of special flight safety measures.

Putin’s Il-96-300 office can be called the “Flying Kremlin”; there are meeting rooms, a conference room, and luxury salons for accompanying persons and guests.

On board the aircraft there is everything necessary for governing the state, there are computers, office equipment, satellite communication systems, special communications, radio-electronic equipment at hand, a lower stairway is built in (so that the story of 1959 with Nikita Khrushchev does not repeat itself) and the engines are modernized (PS-90A).

Also on board there is a small gym, rooms for relaxing selected guests, a refectory, a bar room, shower cabins, a medical room, where, in addition to emergency medical care, resuscitation can be performed.

The technical specifications inspire confidence. The dimensions of the aircraft also leave no one indifferent: the wingspan is 60 meters, the length is 55 meters, and the height is more than 17 meters. Take-off maximum weight 230 tons. Fuel reserve is 150400 liters. The flight speed is about 900 kilometers per hour, when landing - 270 kilometers per hour. Over 20 years of operation, the aircraft made about 12 thousand landings.

The aircraft landing gear has three main supports, which are located behind the center of mass, and a front support. Each of the three is equipped with a four-wheeled cart with brake wheels, and the front one has two non-braking wheels. All fourteen wheels have the same dimensions of 1300x480 millimeters.

The aircraft's power plant is four PS-90A turbofan engines (designed by P.A. Solovyov). The fuel system is automatic, but if necessary, you can use manual control. The fuel is in 9 tanks, of which 8 are located in the wing consoles and one in the center. For each of the four engines the system is designed separately. The consumable compartments are constantly filled with fuel, which ensures its reliable supply to the engines in all flight modes.

Safety first

Il-96 is a reliable aircraft. During their operation, which is more than 20 years, such aircraft have not had a single serious accident, but the news often talks about plane crashes of other brands of aircraft.

Firstly, about 30 aircraft of this brand were built and excellent craftsmen worked on each one individually; secondly, they are prepared for specific operators, and from this it follows that the quality of service is always at its best. The state of the aircraft is monitored by a detachment from the Presidential Administration Department, and this is more reliable than any private airline.

Currently, the special squad has four Il-96-300 of different modifications. The main one is the Il-96-300PU(M), an updated model.

The Il-96-300 presidential aircraft is protected not only from the ground, but also in the air. Many air traffic controllers and a large number of air defenses control the moment during takeoff and landing of Air Force One, because that is when terrorists mainly try to attack.

In the air, Air Force One is protected by a cover team, and these, as you know, are experienced, qualified pilots. There are also additional security measures. For example, if a missile was torpedoed to destroy an aircraft, then its own on-board device will eliminate the attack using an anti-missile. The airliner is also protected by neutralizing heat traps; in addition, it has a camouflage coating on the aircraft body, thanks to which it becomes invisible to missile guidance systems. It turns out that if a missile is torpedoed from the ground, the plane will destroy it.

In contact with

Il-96-400M is a promising project for deep modernization of the Il-96 airliner. Increased capacity, improved flight and economic characteristics suggest the return of the aircraft to the commercial air transportation market.

Il-96-400– wide-body long-haul passenger airliner. It is a deeply modernized modification of the basic Il-96-300 aircraft. An improved version of the Il-96-400M is being developed.

The passenger version was not produced due to lack of orders.

Story

Il-96M

In 1988, the newest Soviet long-range wide-body airliner Il-96, which received an additional index of -300, made its first flight. Equipped with new on-board equipment and engines, the Il-96-300 was significantly superior to both the long-range Il-62 and its direct ancestor, the Il-86. However, among its advantages over its predecessors there was one more - the Ilyushin team took into account the problems that arose when trying to modify the Il-86 and, when creating the Il-96, invested in it huge potential for modernization in various directions. All this could have made the airliner very successful if not for the collapse of the USSR and the sharp weakening of the aviation industry of the new Russia. The IL-86 ceased to be produced by 1997, and although the IL-96 was retained, it is produced individually.

However, the modernization potential of the aircraft worked well in its favor. In 1993, on the wave of euphoria and mutual friendship between the Russian Federation and the United States, the updated Il-96M was lifted into the air - the first-ever brainchild of joint work between aviators of the two countries. The aircraft received a fuselage extended by as much as 8.5 meters, American avionics and Pratt & Whitney PW2337 engines (from the family of engines used on the Boeing 757 and C-17 Globemaster III). At the same time, the capacity increased to 435 people, the maximum take-off weight to 270 tons, and the range to 12,800 km (similar indicators of the IL-96-300: capacity of 300 people, maximum take-off weight of 250 tons, range of 9,000 km). The airliner even received an FAA certificate, but, of course, did not see much demand: it’s 1997 - the United States has a lot of its own aircraft, but in Russia there is no money for such airliners. As a result, the plane returned to its homeland for some time, received old NK-86 engines and appeared at MAKS-2003 under the symbol Il-96-400. In 2009, the plane was cut down.

Il-96-400

However, the very impressive performance of the Il-96M did not allow it to sink into history forever. Moreover, in the 1990s, large twin-engine airliners had not yet conquered the skies, and in Europe the Airbus A340, which was similar in characteristics, was gaining popularity.

The Ilyushin team decided not to let go of the opportunity and created a new version based on the Il-96M, replacing foreign components with Russian ones. They left him with the designation Il-96-400, but it was a modernized vehicle: the onboard systems were improved, and new, forced PS-90A1 engines with a thrust of up to 17.4 tf were installed under the wing (regular PS-90A with a thrust of 16 tf were not able to pull the heavier vehicle) . Attempts to sell the passenger version were unsuccessful, but the cargo version of the Il-96-400T was more successful: several aircraft were operated by Atlant-Soyuz and Polet airlines, but by 2017 both of them ceased to exist. One of the aircraft for the Flight is modified into a version of the VKP - an air command post. Also, the Ministry of Defense announced the purchase of a trial batch of the Il-96-400 tanker version. There is information about a potential large order for 30 aircraft in the future.

Power point

The main power plant of the Il-96-300 is PS-90A engines with a thrust of up to 16 tf. The IL-96-400 is 20 tons heavier than its younger brother and to ensure the required flight characteristics it is equipped with four PS-90A1 engines, the thrust of which reaches 17.4 tf each. A very serious drawback of the PS-90A family of engines has always been considered to be their rather low reliability and low maintainability. Often, the main problem with the commercial operation of the Il-96 was its engines. However, over the course of many years these engines have been improved to acceptable performance and the PS-90A1, A2, A3 engines can already be considered acceptable. Versions of these engines are equipped with the Il-76MD-90A, also known under the designation Il-476.

However, it’s one thing that a good engine for military transport is one thing, and another thing is that it’s a fairly cheap and economical engine to operate for a commercial airliner. PS-90 was developed back in the 1980s and can no longer be called the cutting edge of modern progress. Of course, the first thing that comes to mind when pronouncing the phrase “new Russian aircraft engine” is the PD-14. PD-14 is the latest and most promising aviation jet engine, which is being developed primarily for the MS-21 medium-haul airliner. In addition, the aviation industry management is clearly betting on this engine in the long term. However, with all its advantages, the engine has a drawback - with its thrust of 14 tf, it is not powerful enough to be installed on the Il-96-400M. The option of installing the PD-14M - a forced version of the PD-14 with a thrust of already 15.5 tf - is often discussed - it is being made for the promising, larger version of the MS-21-400. However, this is not enough, even taking into account the possible reduction in the weight of the airliner due to less fuel or lighter materials.

The solution is the PD-18 - an engine created on the basis of the PD-14. With a thrust of 18-20 tf, it is closest to what should be under the wing of the Il-96-400M. However, at the moment it is unknown when this engine will be created and put into production. Perhaps, taking into account the modernization of the IL-96, the creation of this engine will be accelerated.

So for the Il-96-400M there are 3 options:

• PS-90A1 - available, but outdated
• PD-14M - promising, but not powerful enough (the limits of effective boost are unknown, perhaps it can be accelerated to 17-17.5 tf)
• PD-18 - the most best option, but the timing of its creation is still unknown

Il-96-400M and ShFDMS

SHFDMS - Sh Iroko F usable D alne M backbone WITH The aircraft, also known as the CR929, is a project for a new wide-body long-haul airliner with a capacity of 250-300 seats. The aircraft is being created jointly by the Russian UAC and the Chinese Comac.

It is assumed that this aircraft will appear in the mid-2020s. It will be equipped optionally with European or American-made engines (Rolls-Royce, Pratt & Whitney or General Electric), and then with Russian PD-35 engines.

At first glance, it may seem that Russia is creating two long-haul airliners at once, which, given the economic situation, is strange. However, it is necessary to keep in mind that these aircraft belong to different market niches:

The CR-929 seats 250-300 passengers, while the Il-96-400M seats 330-435 passengers. That is, in the IL-96 line it goes one step higher, the CR-929 is different and complementary aircraft.

Il-96-X

In addition, by the end of the 2020s, when the CR-929 receives the PD-35, the same engine may become the basis for the power plant of the updated Il-96 - let's call it conventionally - X.

This is the same version of the IL-96 with two engines, which has been discussed in expert circles and in the media for a very long time.

Taking into account the experience of creating the CR919, the IL-96-X can receive not only new engines, but also a twin-engine design, improved hardware and a new, black wing. Under such conditions, the Il-96 may not be a bad aircraft at all.

IFC proposes to make a salon at 415

However, in the current iteration, the Il-96-400 still does not meet the requirements of customers (whether government agencies or commercial organizations). It requires modernization, which will be discussed below: