The concept of a combat helicopter in the process of formation has come a long way of changes and improvements. One of the key issues was the development of ideas about the most effective tactics for using a rotary-wing attack aircraft, the corresponding weapons complex and, consequently, the scheme and layout of the combat vehicle. During the design of the Mi-24 airborne infantry fighting vehicle, the developers and customers had new ideas regarding the prospects for the further development of helicopters of this purpose. In parallel with the concept of a transport-combat helicopter, designed to increase the mobility of motorized rifle troops and simultaneously provide their fire support, M. L. Mil and his associates conceived a project of a specialized highly maneuverable rotary-wing air tank, which would serve as a flying platform for installing all kinds of weapons. … In this version, the transportation of the landing was no longer provided. The increased interest in such a rotorcraft was largely due to the construction in the USA (by Lockheed) of the high-speed and maneuverable AN-56A Cheyenne combat rotorcraft, which was widely advertised by the Western press.
To achieve high tactical and technical performance comparable to the characteristics of attack aircraft. The AN-56A was equipped with a pushing propeller, a wing, a rigid hinged rotor, and a complex set of aiming and flight-navigation equipment.
The decree of the Central Committee of the CPSU and the Council of Ministers of the USSR on the creation of the Mi-24, adopted on May 6, 1968, provided, among other things, for the development on its basis of a promising model of a rotary-wing attack aircraft with a higher flight speed, good stability and maneuverability. By the end of the year, the advanced design department of the cost center completed the first project of the Mi-28 rotorcraft, which was a further development of the Mi-24 without an amphibious cargo cabin, but with a rigid main rotor, additional propulsion means and reinforced armament. Unfortunately, the customer's lack of clear ideas about the appearance of such a device, the large workload of the company with current work, as well as the illness and death of M. L. Mil did not allow the new concept to be immediately implemented.
For the in-depth design development of the Mi-28 combat rotorcraft (product 280), employees of the MVZ them. ML Mil, under the leadership of the new chief designer M. N. Tishchenko, returned in 1972, when research was already in full swing in the United States under the program of a similar army helicopter-attack aircraft AAN. The lead designer at the early stages was M. V. Olshevets. By this time, the command of the Soviet Air Force had formed the basic requirements for a promising machine. The rotorcraft was supposed to serve as a means of supporting ground forces on the battlefield, destroying tanks and other armored vehicles, escorting helicopter assault forces, and fighting enemy helicopters. The main weapons were supposed to use guided missiles of the Shturm anti-tank complex (up to eight missiles) and a 30-mm movable cannon. The total mass of the combat load was estimated at 1200 kg. The cockpit of the crew, consisting of a pilot and an operator, and the main units of the helicopter were supposed to be protected from being hit by weapons of 7, 62 and 12, 7 mm caliber, the flight and navigation complex was to ensure operation at any time of the day and in any weather conditions. The maximum speed of the car was planned to be 380-420 km / h.
Models and layouts of preliminary versions of the Mi-28 helicopter
Emergency landing crew survival system
Constructors cost center them. ML Mil conducted aerodynamic, strength and weight calculations of promising projects, worked out various options for power plants, schemes and layouts of the Mi-28. Since the customer demanded that the helicopter be equipped with an emergency escape system, and the practice of flight tests carried out at the Mil company showed the complexity of ensuring the safe shooting of the blades, the developers considered a twin-rotor rotorcraft of the transverse scheme as a priority. It not only guaranteed safe ejection outside the propeller discs, but also made it possible to include a rotorcraft wing in the design. In 1973, a project for such a machine with a takeoff weight of up to 11.5 tons was completed, equipped with two TVZ-117F engines with a capacity of 2800 hp. each, with two main rotors with a diameter of 10, 3 m and a pushing propeller. Pilot production built an appropriate layout, units and systems were worked out in the OKB departments.
In the mid 70s. the customer revised the concept of using combat rotorcraft. The tactics of combat operations (by analogy with attack aircraft) at a relatively high altitude and speed gave way to tactics of actions at low altitudes with rounding the terrain, which provided the helicopter with high survivability on the battlefield. In this regard, the designers of the cost center in the early 70s, as an initiative, developed technical designs for a number of combat helicopters without additional propulsion means. Among them are helicopter options: a twin-rotor transverse configuration with rotors with a diameter of 8, 25 m and two GTD-UFP engines with a capacity of 1950 hp. each; a single-rotor scheme with a rotor diameter of 14, 25 m and two GTD-UFP engines; a single-rotor circuit with a main rotor with a diameter of 16 m and two TVZ-117F engines. The latter option was recognized as the most promising for the Mi-28. The Milevites did not consider the twin-screw coaxial scheme because of the fear of the possibility of collision of the rotor blades during combat maneuvering.
Flying laboratory Mi-24 for testing the sighting complex Mi-28 (left). Main gearbox Mi-28. (on right)
The rejection of the rotorcraft scheme made it possible to significantly increase the weight return and combat load, as well as to simplify the design. The adoption of tactics for conducting combat operations at low altitudes made it possible, in addition, to abandon the installation of a bailout system. Studies have shown that when a helicopter was hit at low altitudes, the crew did not have time to eject - they had to rely only on the strength of the vehicle's hull and means of survival. The concept of using safely deformable structures, energy-intensive chassis and energy-absorbing seats, which was born in the same years, created the prerequisites for ensuring the survival of the crew of a downed helicopter without obligatory ejection. Based on this, the designers preferred to return to the structurally simpler classical single-screw scheme. As a power plant, they chose a modification of the powerful, reliable TVZ-117 engines already mastered by the industry.
The search for the most rational appearance of the helicopter was accompanied by the coordination of requirements for the weapon system, sighting, flight and navigation complex and other components, blowing of models in a wind tunnel, forming assessment methods and determining ways to increase combat survivability and survival, reduce visibility, carried out in specialized scientific research research, development and flight test organizations, the main among which from the very beginning of the design were TsAGI, NIIAS, LII, VIAM, GNIKI VVS. Kolomna Design Bureau for Mechanical Engineering, Central Design Bureau "Sokol", Ramenskoye Instrument Design Bureau for MAP, etc. Every year more and more customer organizations, ministries of aviation, defense, radio engineering and other industries were involved in the development of a promising aiming, flight and navigation system and weapons for a combat helicopter. The design of the Mi-28 gradually took on the character of a national comprehensive program, comparable in complexity of the tasks to be solved with the construction of a new promising combat aircraft.
By 1976, the outward appearance of the Mi-28 was largely determined. All work on the combat vehicle was headed by Deputy Chief Designer A. N. Ivanov, M. V. Vainberg was appointed the responsible leading designer. A whole group of leading designers was subordinate to him, each of whom was responsible for a separate direction of the grandiose program. Developed at the MVZ them. ML Mil's technical proposal received a positive assessment from the customer. A circle of co-executors for systems and complexes has been formed.
Simultaneously with the Milians, the project of the B-80 combat helicopter was proposed to the government by the Ukhtomsk Helicopter Plant named after V. I. N. I. Kamov. Experts from the Kamov Design Bureau, having experience in the use of coaxial twin-rotor helicopters on ships, came to the conclusion that the devices of such a scheme would also be effective in solving fire support tasks for ground forces. The Kamovites proposed an original concept of an attack helicopter with one crew member. The functions of the second crew member were to a large extent to be taken over by the electronic complex.
The first experimental prototype of the Mi-28
On December 16, 1976, the Central Committee of the CPSU and the Council of Ministers of the USSR adopted a resolution on the development of the Mi-28 and V-80 (hereinafter Ka-50) helicopters on a competitive basis, and both firms began draft designs. Since there was no specific tactical and technical assignment from the Air Force, the specialists of the Cost Center and UVZ were given wide freedom of action. An unprecedented competition in the history of aviation began, in which the creators of rotary-wing aircraft had to invent and develop the concepts of combat helicopters themselves, based on their own understanding of the tasks facing the machine, and how to perform them, and then prove the prospects of their concepts to the customer. As a result, firms began designing machines of a completely different class, differing in aerodynamic design, takeoff weight, crew, weapons, equipment, etc. Unlike the Kamov B-80, which has no analogues, the Mi-28 helicopter was designed at the Moscow Helicopter Plant. M. L. Mil in accordance with the concept of a two-seater combat vehicle, adopted throughout the world and confirmed its viability in real combat operations, with a clear division of functions (piloting, observation, target recognition, aiming, communication and weapon control) between the two crew members. As a prototype, the Milians took the Mi-24 and the best foreign helicopter of a similar class - the American AN-64 Apache, which was to be surpassed in terms of basic parameters.
Creating the Mi-28, the designers of the Mil Moscow Helicopter Plant, in order to achieve weight perfection with the necessary strength, reliability and combat survivability, applied new methods of optimal design, tested in the creation of the Mi-26 heavy truck. The preliminary design was accompanied by the elaboration of numerous layout options, including the original fuselage layout with the so-called "central core", i.e. with the placement of all vital parts and systems in the central longitudinal power frame, along the sides of which compartments with equipment and secondary units were located. However, the calculations showed the difficulty of achieving the necessary vibration and strength characteristics, the vulnerability of the equipment and forced to abandon the attractive scheme and return to the traditional layout of the all-metal semi-monocoque fuselage.
The designers decided to provide combat survivability with duplication of units with their maximum separation and mutual shielding, wired up more important units with less important ones, a combination of armor, the choice of materials and dimensions of the structure, excluding catastrophic destruction of the structure in case of damage in a time sufficient to complete the task and return to the base.
One of the key elements was the cockpit layout. Milevtsy immediately abandoned the location of the crew members nearby, since such a scheme did not provide the necessary viewing angles for the pilot and the operator, and also made it difficult to escape the helicopter. The most successful was the "tandem" scheme (the pilot's seat was raised above the operator's seat), i.e. a scheme proven by life on the Mi-24. In the future, the correctness of the choice was confirmed by world experience. During the design of the Mi-28, the pilot production of the cost center built many mock-ups and models, including successively six full-size helicopter mock-ups, which made it possible to optimally assemble the combat vehicle.
The most important element that fundamentally distinguished the Mi-28 from the Mi-24 was the engine spacing. This measure, firstly, guaranteed against the simultaneous destruction of both engines, and secondly, the engines were an additional shielding element that protected the main gearbox and the helicopter control system.
By the end of 1977, the designers of the MVZ them. ML Mil completed the draft design, and also agreed with the subcontractors all programs for the creation of component systems for equipment and weapons. The next year and a half were spent on agreeing with the customer on all aspects of the tactical and technical assignment for the helicopter and its complex, and in 1979 the OKB began detailed design of the rotorcraft and tests of the first experimental prototypes of units and systems.
When designing the helicopter assemblies, options for various schemes and design solutions were worked out, new materials were widely introduced with strict adherence to weight and strength control. In particular, as alternative options, the specialists of the cost center designed and built two types of fundamentally new bushings for the Mi-28 main rotor: elastomeric and torsion, and also tested, along with the tail rotor, which has a traditional blade pitch control method, an experimental tail rotor with a controlled flap., transmission shaft made of carbon fiber. The choice of the most promising solutions was accompanied by comprehensive tests of the units at the stands. A total of 54 stands were created, including a full-scale stand, a stand for automatic static tests, an electric propeller stand for testing the main gearbox, stands for testing elements of bushings, blades and other units, a unique model stand for testing the crew survival system during emergency landings, as well as a stand for studying the impact of overloads on a person and testing rescue systems.
To conduct preliminary flight tests of units (elastomeric and torsion bushings and rotor blades, tail rotor, TVZ-117VM engines) and systems (autopilot, sighting, navigation and aerobatic system and guided missile weapons), the pilot production converted four Mi-helicopters into flying laboratories. 24, and then several Mi-8s.
Constructors cost center them. M. L. Mila, together with subcontractors from specialized design bureaus and research institutes, conducted experimental research on programs to ensure high combat survivability and low thermal signature, in particular ballistic tests for survivability of the cockpit, fuel tank, main and tail rotor blades, transmission shaft, control rods and hydraulic systems. Based on the results of these tests, the design and placement of the armor protection were optimized. For the first time in the domestic helicopter industry, the characteristics of the thermal radiation of a helicopter at all azimuths have been experimentally determined. In addition, by joint efforts, a set of experimental and computational studies was carried out to create a passive protection system for the helicopter crew, the operability of safely damaged emergency depreciation and fixation equipment was tested - chassis, shock-resistant seats, a moving floor, etc.
Mi-28 (side No. 012) in the first flight
The first copy of the Mi-28 is being tested
In August 1980, the Commission of the Presidium of the Council of Ministers of the USSR on military-industrial issues, having familiarized itself with the development of the promising Mi-28 combat helicopter, decided to build two experimental prototypes, without waiting for the official approval of the final layout. The positive conclusion of the mock-up commission followed only at the end of next year, when the assembly shop of the plant had already transferred the first helicopter model for static tests and was building the first flight copy. Therefore, the first sample of the Mi-28, assembled in July 1982, was refined to the required level in the process of fine-tuning and flight tests.
The Mi-28 two-seater combat helicopter was built according to the classic single-rotor scheme and was intended for search and destruction in conditions of opposition from armored vehicles, enemy manpower in open and rugged terrain, as well as low-speed air targets with visual visibility in simple and limited weather conditions. The dimensions of the helicopter made it possible to transport it on Il-7b military transport aircraft with minimal disassembly. Constructive solutions and the layout of the main units ensured the autonomy of combat operations from sites outside the airfield for 15 days.
The fuselage of the Mi-28 included the bow and central parts, as well as the tail and keel booms. In the bow there were two separate armored cockpit compartments, in which the navigator-operator's seat was located in front, and the pilot's seat in the back and above. A combined observation and sighting station KOPS and a cannon mount were attached to the front and bottom of the bow. Under the floor of the pilot, blocks of electrical equipment and an aiming-flight-navigation complex were placed.
ATGM 9M120 complex "Attack-V" and block NAR B-8V20
To increase the combat survivability of the helicopter and the survival of the crew, armored protection of the cockpit was provided, which included a set of ceramic tiles glued to the frame of the nose of the fuselage. In addition, silicate bulletproof glasses played a protective role. The pilot and navigator were separated by an armored partition. The navigator's door was on the left side, and the pilot's door was on the right. Doors and glass were equipped with emergency release mechanisms. In case of emergency leaving the cabins, special ladders were inflated under the doors to protect the crew from hitting the chassis.
The main gearbox, fan, auxiliary power unit, hydraulic unit, and air conditioning units were mounted on the ceiling panel of the central part of the fuselage. To the right and left of the axis of symmetry, engines and bevel gears, as well as wing consoles, were installed on the ceiling panel and cantilever elements of the frames. In the lower part of the fuselage there was a container for fuel tanks, on the upper panels of which there were equipment blocks. The placement of the heaviest units and systems near the center of mass contributed to the increase in the Mi-28's maneuverability. The rear compartment of the radio equipment had sufficiently spacious free volumes that made it possible to use it as a cargo one (for transporting airfield equipment when relocating a helicopter or evacuating the crew of another helicopter). The simplicity and convenience of servicing various systems and equipment of the helicopter were provided by numerous doors and hatches along the sides of the fuselage. The lower location of the tail boom excluded the possibility of the main rotor blade touching it during a sharp maneuver. The rear part of the keel boom was made in the form of a fixed rudder, inside which was placed the cable wiring for controlling the tail rotor and stabilizer, which was attached to the upper part of the keel boom. The stabilizer control was connected to the main rotor pitch knob. Under its lower part was the tail landing gear.
The main landing gear of the Mi-28 helicopter
The wing of the helicopter is a free-carrying wing with four pylons designed for suspension of missile, small arms and cannon, bomb weapons and additional fuel tanks. The wing pylons are equipped with modern DBZ-UV beam holders. Their feature is a removable lock, which made it possible to place an integrated weapon suspension system in the wing, which does not require special ground equipment. At the ends of the wing in fairings were devices for shooting jamming cartridges. In an emergency, the wing could be dropped.
The system of passive protection of the helicopter was supposed to ensure the safety of crew members during an emergency landing with a vertical speed of up to 12 m / s. At the same time, the values of the overloads decreased to the level of physiologically tolerable ones. The mechanisms that activated the protection system were installed on the shock absorber cylinders of the main landing gear. With their help, the sinking of the energy-absorbing crew seats and the forward deflection of the longitudinal-lateral control handle were carried out, which excluded the possibility of injury to the pilot. Energy-absorbing seats, lowering by 30 cm, protected the crew from overloads that occur during an emergency landing. In an emergency situation, the forced trauma-safe attraction of the pilots to the back of the seat was also provided with a harness.
The choice of the Mi-28 chassis scheme - three-support with a tail wheel, was dictated by the need to place a turret gun mount with a wide firing sector under the nose of the helicopter, as well as a limitation on the dimensions of the vehicle associated with the conditions of its transportation. Hydropneumatic shock absorbers with an additional emergency running were included in the design of the landing gear. The main lever-type supports made it possible to change the clearance of the helicopter.
The blades of the five-bladed main rotor had a profile recommended by TsAGI and a rectangular shape in plan. The spar of the blade - made of polymer composite materials, formed the nose in the shape of the profile. The tail compartments were attached to it, made in the form of a skin made of polymer composite materials with a polymer-core filler. The main rotor hub was a titanium body with five external spherical elastomeric hinges. Fluoroplastic and fabric bearings were widely used in the movable joints of the bushing. Such "maintenance-free", i.e. which does not require permanent lubrication, the bushings were first used in the domestic helicopter industry. The elastomer sleeve not only made it possible to reduce labor costs for servicing the helicopter, but also ensured an increase in the maneuverability and controllability of the machine. (The use of an alternative torsion bushing on the Mi-28 was abandoned.)
The four-bladed tail rotor has been designed in an X-pattern to reduce noise and increase efficiency. Its sleeve consisted of two modules mounted one above the other on the hub spokes. Each module was an articulation of two arms of the blades. The blade included a fiberglass spar and a honeycomb block and fiberglass tail section.
The main and tail rotor blades were equipped with an electrothermal anti-icing system.
Mobile unit NPPU-28 with a 2A42 cannon of 30 mm caliber
Unfortunately, the development of the X-shaped tail rotor was delayed and on the first experimental Mi-28 until 1987, the tail rotor was used from the Mi-24.
The power plant included two TVZ-117VM turbo engines with a capacity of 1950 hp.each, independent operation of which ensured the possibility of flight with one working engine. Mushroom-shaped dust protection installations were installed at the engine entrances. The engines were equipped with screen-exhaust devices that reduce the helicopter's thermal signature. The water injection system ensured a surge-free operation of the engines when launching unguided missiles.
An AI-9V engine was used as an auxiliary power unit, which also provided a drive for systems during tests on the ground and a supply of warm air for heating the cabins. A fan and oil coolers were located in the engine compartment of the gear compartment, above the ceiling panel of the central part of the fuselage.
The Mi-28 fuel system was made in the form of two independent symmetrical power systems for each engine with automatic cross-feed and pumping. It consisted of three tanks (two consumable for each engine and one common), located in a container of fuel tanks, the walls of which were protected with foam rubber. The fuel tanks themselves were filled with explosion-proof polyurethane foam.
A feature of the helicopter transmission was the presence of two angle gearboxes UR-28, which serve to transmit torque from the engines to the main gearbox VR-28 and are the first stages of reduction.
The control system involved four combined steering drives installed on the main gearbox, which served as hydraulic boosters and steering gears for the autopilot. The hydraulic system of the Mi-28 consisted of two independent systems serving to power the combined steering drives of the control systems and the hydraulic damper in the directional control system.
The helicopter equipment also included a pneumatic system, an air conditioning system and oxygen equipment.
A set of instrumental equipment was installed on the Mi-28 helicopter, which made it possible to fly the helicopter and solve air navigation problems at any time of the day and in any meteorological conditions.
To solve combat missions, as well as perform flights, the helicopter was equipped with: a guided missile weapon system. including a combined observation and sighting station (KOPS) developed by the Cherkasy plant -Fotopribor-, designed for the navigator-operator to search, recognize and track targets when launching guided missiles and firing a cannon; helmet-mounted target designation system for the pilot, which controls the gun; sighting-flight-navigation complex PrPNK-28. For aiming and firing from fixed types of weapons, an indicator on the windshield - ILS-31 was installed in the cockpit. The PrPNK-28 complex created by the Ramenskoye Instrument-Making Design Bureau provided aimed shooting and bombing, improved flight characteristics, flight along a given trajectory, motionless hovering over a given point, altitude stabilization, and continuous position determination. The complex consisted of primary information sensors, two on-board computers and control and display devices. As sensors were used: vertical information systems. course, altitude and speed parameters, Doppler speed and drift meter and helmet-mounted target designation system. The control and display devices included: an automatic tablet, navigation devices and an information display system.
The second experimental prototype of the Mi-28 (side No. 022)
The armament of the Mi-28 consisted of a non-removable mobile gun mount NPPU-28 with a powerful 2A42 cannon of 30 mm caliber developed by the Tula Instrument Design Bureau and a removable armament system suspended on the wing pylon holders. Like most combat helicopters in the world, the Mi-28 was equipped with a cannon that could rotate at large angles, which made it possible to fire from various types of weapons simultaneously at two targets located at different azimuths (the gun is similar to that installed on the BMP-2 infantry fighting vehicle). The non-removable mobile gun mount NPPU-28 was developed by the specialized enterprise MMZ "Dzerzhinets". A feature of the NPPU-28 was the simplicity and reliability of the supply of shells to the gun. The 2A42 cannon had a selector power supplied from both sides, in this regard, the installation provides two independent shell boxes, rigidly connected to the receiving windows on the gun. When moving the barrel of the gun in elevation and azimuth, the shell boxes repeat its movement. During operation, the boxes can be equipped with two different types of projectiles. The deviation range of NPPU-28 was: in azimuth ± 110 °; in elevation + 13-400. Cannon ammunition 250 rounds. The removal of ammunition increased the reliability of the weapon and the survivability of the helicopter. The external beam holders provided for the suspension of up to 16 anti-tank guided supersonic missiles 9M120 of the Ataka-V complex or 9M114 of the Shturm-V complex (with radio command guidance systems) placed on two-story launchers APU-4/8. Guided missile armament -Ataka-V- was developed by the Kolomna Machine Building Design Bureau, designed to defeat not only ground targets, but also low-flying low-speed air targets. On the inner holders, blocks of unguided missiles B-5V35, B-8V20 or B-13L1, unified GUV helicopter gondolas in machine gun and grenade launcher versions could be attached. The holders could also carry containers of small cargo KMGU-2 with mines, aerial bombs of 250 and 500 kg caliber or additional fuel tanks. In subsequent years, the Mi-28 arsenal was replenished with S-24B heavy unguided missiles, UPK-23-250 cannon containers and ZB-500 incendiary tanks.
The third copy of the Mi-28 - the Mi-28A helicopter (tail number 032)
In terms of security characteristics, the Mi-28 helicopter has no equal in the world helicopter industry. The cockpit is made of aluminum sheets, which are glued with ceramic tiles. The cab doors have two layers of aluminum armor and a layer of polyurethane between them. The cab windshields are 42 mm thick transparent silicate blocks, while the side windows and door windows are made of the same blocks, but 22 mm thick. The cockpit is separated from the cockpit by aluminum armor plate, which minimizes the defeat of both crew members with one shot. Fire tests have shown that the sides can withstand shell fragments from the American 20-mm Vulcan cannon, the windshield - 12.7 mm bullets, and the side windows and door windows - 7.62 mm.
The Mi-28 was protected from being hit by guided missiles: equipment for jamming radar stations and guided missiles with infrared and radar homing heads; equipment for warning about irradiation of a helicopter by radar stations and enemy laser designators; device for firing jamming cartridges UV-26 to protect against missiles with thermal homing heads.
Upgraded X-shaped tail rotor
During the development of the helicopter, great importance was attached to the convenience of maintenance in the conditions of autonomous basing. Compared to the Mi-24, the complexity of maintenance has been reduced by about three times.
Several months after the completion of the assembly, it was spent on the ground debugging of the units and systems of the first Mi-28, and on November 10, 1982, the crew consisting of the leading test pilot of the plant G. R. Karapetian and the test navigator V. V. Tsygankov for the first time tore the new helicopter away from land, and on December 19 of the same year - made the first flight in a circle. All parts and systems of the helicopter worked satisfactorily, and the next day the official transfer of the rotorcraft to the first stage of joint comparative state tests (SSGI) took place. They were safely completed in 1984, and the helicopter entered the Air Force State Research Institute of Civil Aviation at the second stage of the SSGI (Air Force stage). The factory pilots Yu. F. Chapaev, V. V. Bukharin, V. I. Bondarenko and B. V. Savinov, navigator V. S. Cherny made a great contribution to the testing of the combat helicopter. The leading flight test engineers were V. G. Voronin and V. I. Kulikov.
The first model of the Mi-28 was intended primarily for flight performance measurements and did not carry a weapon system. It was installed on the second flight copy, the assembly of which was completed by the pilot production of the cost center in September 1983. All the comments of the Air Force model commission were taken into account in its design. At the end of the year, the second flight copy entered the SSGI weapons range tests. At first, flight tests of both machines were complicated by the insufficient resource of the transmission and the carrier system, but then the designers brought the resource of the main units to several hundred hours and thus ensured the successful completion of the SSGI program.
In the course of comparative joint tests of the first flight model of the Mi-28 by 1986, all the specified performance characteristics were confirmed, and in some parameters even exceeded. The customer's request was limited only to expanding the range of permissible overloads due to the fact that the helicopter control margins made it possible to perform maneuvers with their higher values. After appropriate revision of the blades and the hydraulic system, this problem was also solved. As a result, the vertical overload in the "hill" mode was 2, 65 at an altitude of 500 m and 1, 8 at an altitude of 4000 m. The maximum flight speeds "sideways" and "tail-first" also significantly increased.
On the second flight copy, in the same year, all work was completed on fine-tuning the special helicopter complexes and ensuring the compatibility of weapons with the machine. The weapons were successfully tested at the Gorokhovets test site, including the first experimental night launch of guided missiles from a helicopter against ground targets.
After the installation of the X-shaped tail rotor on the first flight prototype in 1987, the appearance and equipment of the combat helicopter were finally determined.
M. N. Tishchenko, S. I. Sikorsky and M. V. Vainberg near the Mi-28A at the Paris air show, 1989
The impressive results of the first tests of the Mi-28 allowed the Ministry of Aviation Industry in February 1984 to decide on the preparation of its serial production at the Arsenyev Aviation Production Enterprise. With a favorable set of circumstances, the Soviet Air Force could have received the first Mi-28s already in 1987, however, this was not destined to come true. Despite the fact that research carried out in the United States proved the impossibility of creating a full-fledged single-seat combat helicopter at the current level of development of American electronics, Soviet military experts came to the opposite conclusion, believing that our instrument-makers would be able to create an automated complex that would allow a single-seat combat helicopter to operate effectively near the ground. In October 1984, the customer made his choice, giving preference to the B-80 helicopter for further development and serial production in Arsenyev.
In April 1986, the Mi-28 and V-80 were tested simultaneously for detection, recognition and imitation of target destruction, during which the Mi-28 proved its advantages. Nevertheless, the customer's specialists, without waiting for the end of the comparative tests, on the basis of theoretical calculations, came to the conclusion that the B-80 has a greater development potential and requires lower costs for the creation and maintenance of a helicopter group. To improve the performance indicators of detection and recognition of targets, the military proposed for the B-80 a technique of hardware target designation from a special reconnaissance helicopter or ground-based guidance systems. However, such a two-seater target designator helicopter still had to be built, and the instrumentation and armament of the B-80 had to be brought to a working condition. Therefore, no one dared to close the Mi-28 program, only the amount of funding was cut. -Contest- continued, but in unequal conditions. Despite this, the Mi-28 successfully completed a significant part of the state tests, proving the high efficiency of its onboard systems and weapons. Taking into account the positive results of the SSGI, the Central Committee of the CPSU and the Council of Ministers of the USSR issued a Decree of December 14, 1987 on the completion of tests on the Mi-28 and the beginning of serial production at the Rostov helicopter plant. The further program for improving the helicopter envisaged the creation at the first stage of the modernized day-time helicopter Mi-28A, and then its "night" version of the Mi-28N, capable of conducting combat operations in adverse weather conditions at any time of the day.
The construction of the third flight copy of the Mi-28, the design of which took into account all the customer's comments and changes made to the prototypes as they were fine-tuned, the pilot production of the Moscow Helicopter Plant. M. L. The mile began in 1985. The upgraded helicopter was named Mi-28A in 1987. It differed from the first experimental prototypes by the modernized TVZ-117VMA high-altitude engines with a capacity of 2225 hp. each with improved instrumentation, redesigned ejector exhaust devices, and redesigned main gearbox. At the ends of the wings, containers with cassettes of infrared and radar passive interference appeared (on the first two Mi-28s were not installed).
Mi-28A (tail number 042) - the fourth prototype, 1989
Mi-28A on tests in the Caucasus mountains
Tests of the upgraded Mi-28A began in January 1988. They went well, and the following year the helicopter was demonstrated for the first time at the Le Bourget air show in Paris and at the exhibition in Red Hill near London, where it was a huge success with visitors. In the same year, the first experimental Mi-28 helicopter was officially presented for the first time in its homeland during the aviation holiday in Tushino. In January 1991, the second Mi-28A, assembled by the pilot production cost center, joined the test program. In September 1993, during the combined-arms exercises near Gorokhovets, the helicopters brilliantly demonstrated their flying qualities and combat superiority over competitors. The feasibility of choosing a two-seater layout became obvious to everyone.
The Mi-28A helicopter was highly appreciated by both domestic and foreign specialists. It fully corresponded to its purpose and surpassed all helicopters of a similar class in many respects. The aerobatic and maneuverable characteristics guaranteed a high degree of survival in aerial combat. With the exception of its younger brother, the light training and sports Mi-34, the combat Mi-28 is the only helicopter in Russia capable of performing aerobatics. On May 6, 1993, test pilot G. R. Karapetian for the first time performed the Nesterov loop on the Mi-28, and a few days later - the "barrel".
The Rostov Helicopter Production Association began preparing for the serial production of the flying tank, and in 1994 began building the first serial model at its own expense.
The leadership of the armed forces of many foreign states became interested in the Russian combat helicopter. In the fall of 1990, an agreement was signed with Iraq on the sale of Mi-28 helicopters, and subsequently on their joint production (Mi-28L - licensed) in Iraq, but these plans were prevented by the outbreak of the war in the Persian Gulf. Autumn 1995The Swedish Ministry of Defense has selected the Russian Mi-28A and the American AN-64-Apach- among various types of combat helicopters for comparative tests. Our rotorcraft has fully completed the test program, including live firing, and has shown itself to be very reliable and well adapted to field conditions.
In 1993, after the end of the first stage of the state tests of the Mi-28A, a preliminary conclusion was received from the customer on the release of an initial batch of helicopters. Military test pilots started mastering the Mi-28A. However, due to insufficient funding, the work was delayed, and the equipment of competing helicopters by this time had become obsolete. In this regard, M. V. Weinberg, who has already become the General Designer of the cost center, with the consent of the customer, decided to stop the development of the Mi-28A at the final stage of state tests and to concentrate all his forces and financial capabilities on the development of the Mi-28N combat helicopter (-N- - night, export designation: Mi-28NE) - round-the-clock and all-weather, with a fundamentally new integrated complex of fifth-generation onboard equipment. The helicopter is seen as a kind of response to the creation by the American firm McDonnell-Douglas of the all-weather flying tank AH-64D Apache Longbow. Subsequently, the correctness of the decision was indirectly confirmed by the tests of the Mi-28A helicopter (in Sweden in October 1995), when the only additional requirement was presented to it - the presence in the future of systems that would allow combat operations at night.
Surveillance and sighting complex Mi-28N
View of the Mi-28N from the tail boom
Considering that the layout and design of the Mi-28, its armament, protection systems met the most modern requirements, it was decided to develop only new equipment on a promising element base and a gearbox. At the beginning of 1993 a mock-up commission of the customer was held and the preliminary design was accepted, after which, despite a severe lack of funding, the development of the Mi-28N "Night Hunter" began.
The Mi-28N / Mi-28NE helicopter is equipped with an integrated fifth-generation avionics and instrumentation system. All equipment interacts via a single interface - a multiplex data exchange channel. The controls of the onboard equipment are integrated into a single compact control system, which made it possible to reduce their number to a reasonable minimum and place them in relatively small cockpits.
The airborne electronic complex provides the use of weapons and the solution of flight and navigation tasks day and night in simple and difficult weather conditions at extremely low altitudes (10-50 m) with automatic rounding of the terrain and overflying (bypassing) obstacles using cartographic information. The complex allows you to detect and identify targets, use weapons; control groups of helicopters with automated distribution of targets between them; conduct a two-way exchange of information on targets between helicopters and air or ground command posts. The complex also provides control over the operation of the power plant, transmission, fuel, hydraulic and air systems; voice notification of the crew about emergency situations and telephone communication.
The complex of onboard radio-electronic equipment includes: a navigation system, an aerobatic complex, an on-board computer system (BCVM), an information and control system; a multifunctional information display system, a weapon control system, an operator's observation and aiming station, a pilot's thermal imaging station, an airborne all-round radar, a missile weapon control system, night vision goggles, a communications complex, a warning system for radar and laser irradiation and radio identification equipment.
Mi-28N in a demonstration flight
Navigation of the Mi-28N is provided on the basis of a system of cartographic information with a high degree of resolution, based on a digital data bank on the relief of the combat area, a high-precision satellite navigation system and an inertial navigation system.
The tasks of searching, detecting and recognizing targets are solved on the Mi-28N due to the presence of the latest observation and sighting station with gyro-stabilized fields of view. The station has optical, low-level television and thermal imaging observation channels. All channels, with the exception of the optical one, have the ability to provide information digitally and display it on the screen. A laser range finder and a missile weapon control system are structurally combined with the observation and sighting station. All generalized information goes to the indicators of the navigator-operator. When developing the observation and sighting station, an unofficial competition was held, in which the Krasnogorsk Mechanical Plant, the Ural Optical and Mechanical Plant, the Cherkassk Fotopribor Plant and the Kiev Arsenal Plant took part. The Krasnogorsk plant was recognized as the winner of the competition.
The airborne radar station located in a spherical fairing on the main rotor hub operates in search and detection modes for small-sized ground and air targets, with the issuance of relevant information on the display and in digital form to the target recognition automation system. The Mi-28N can search for targets, hiding in the folds of the terrain or behind trees, exposing only its "beak" from behind cover. The station also provides information about the obstacles ahead, including detached trees and power lines, in digital form and in the form of a television signal for indication, making it possible to fly around the clock at an extremely low altitude of 5-15 meters even in adverse weather conditions.
The pilot thermal imaging station of the pilot "Stolb" developed by the Central Design Bureau "Geofizika" operated both in the control mode from the onboard computer and in the manual mode. The station was also equipped with a laser rangefinder. At present, the pilot station "Stolb" has been replaced by a more advanced station TO-ES-521, developed by FSUE PO "UOMZ".
All generalized information is fed to multifunctional liquid crystal displays - two in the cockpit and two in the cockpit of the navigator-operator.
The on-board communication system provides on the ground and in flight two-way telephone radio communication between helicopters and ground command posts of the Air Force and Ground Forces; data exchange between helicopters and ground stations; internal telephone communication between crew members in flight and with ground personnel during pre-flight preparation; voice notification of the crew about emergency situations; as well as recording of telephone conversations of the crew on external and internal radio communications. Accordingly, the Mi-28N helicopter has equipment for receiving external target designation.
The Mi-28N has mastered a unified computing environment consisting of two central on-board computers and a number of peripheral computers, which significantly simplified the onboard software. An extensive internal control system has been introduced on the helicopter, which allows autonomous preparation for departure, post-flight maintenance and search for failures without the use of special aerodrome control and verification equipment.
The onboard integrated radioelectronic complex allows the Mi-28N / Mi-28NE crew to work at low altitudes, in battle formations, to carry out assault operations with landing at intermediate sites, to solve combat missions using guided missile weapons from behind shelters, without entering direct contact with a view to and without putting the helicopter at risk of destruction. The radio command guidance system of the supersonic high-precision guided missile "Ataka-V" provides increased noise immunity in front of the laser: it is more adapted to work in smoke, dust, heavy fog. ATGM 9M120V "Attack-V" affects all types of tanks, including those with reactive armor protection. Having determined the targets and their type, distributing them as needed between the group's helicopters, choosing the target for the attack, the Mi-28N crew energetically emerges from the ambush and "processes" the targets with weapons or directs the attack aircraft or other helicopters of the group.
The defense of the Mi-28N / Mi-28NE from enemy aircraft and helicopters, in addition, has been strengthened by the deployment of air-to-air Igla missiles on it. These missiles are used around the clock in the fired-on-forget mode, that is, they are fully autonomous after launch.
The combination of a multifunctional integrated complex of onboard electronic and instrumental equipment, powerful weapons and a passive protection system that has no analogues make the Mi-28N / Mi-28NE-Night Hunter a unique in terms of combat effectiveness and survivability, a rotary-wing combat vehicle that has no analogues among propeller-driven aircraft. …
In addition to the new set of equipment and weapons, the cost center designers installed a number of new structural parts on the Mi-28N, such as, for example, the new multi-threaded main gearbox VR-29 and engines with a modernized automatic control system. The program for the creation of the Mi-28N was headed by the chief designer V. G. Shcherbina. In August 1996, the first Mi-28N was assembled, and on November 14 of the same year, the crew consisting of test pilot V. V. Yudin and navigator S. V. Nikulin performed the first flight on it.
Factory flight tests of the Mi-28N began on April 30, 1997 and, despite the difficult economic situation of the parent company-developer, were successfully completed four years later. The helicopter entered state tests.
Zeroing a gun on a firing stand
Flight at extremely low altitude
Taking into account the great need for military vehicles of this type, the command of the Russian Air Force in 2002 adopted the Mi-28N as the main promising combat helicopter of the future, without waiting for the completion of the tests. In the summer of the following year, the President of Russia Vladimir Putin issued an order to adopt the Mi-28N into service as the main attack helicopter. The Rostov Helicopter Plant OJSC Rosgvertol has started to master its serial production.
On March 4, 2006, the State Commission chaired by the Commander-in-Chief of the Air Force issued an opinion on the release of a pilot batch of Mi-28N, which was the official permission for the plant to carry out serial production of Mi-28N helicopters, and for the customer's units to operate them. Until 2010, the Russian Armed Forces are planning to accept 50 such vehicles. All in all, the Russian Air Force is going to purchase at least 300 "Night Hunters".
Helicopters Mi-28N "Night Hunter" in the summer of 2006 took part in the joint military maneuvers "Shield of the Union" 2006, where they were highly appreciated by the joint Belarusian-Russian command. Equally high was the assessment of the "Night Hunter" and the military attaches of foreign states who were present at the maneuvers. According to their reviews, the real combat readiness and effectiveness of the Mi-28N demonstrated during the exercises exceeded all expectations. The military ministries of a number of non-CIS countries have expressed interest in acquiring the Night Hunters.
With the installation on the Mi-28 helicopter of a complex of onboard electronic equipment, which allows combat operations around the clock and in adverse weather conditions adequately to the actions of the Ground Forces, the Armed Forces of the Russian Federation received a reliable "shield and sword" in the air, and Russia - a new competitive combat helicopter on the world arms market …
The designers of Mil Moscow Helicopter Plant continue to improve the Mi-28N Night Hunter, introducing the latest achievements of domestic and world helicopter science and technology into the design of its units and systems. A number of new modifications of the helicopter are being prepared for the Russian Air Force and for export deliveries, including versions with foreign-made units and systems.
| Basic data |
Mi-28 |
Mi-28A |
Mi-28N |
| Year built | 1982 | 1987 | 1996 |
| Crew, people | 2 | 2 | 2 |
| Evacuation compartment capacity, persons 2-3 * | 2-3* | 2-3* | |
| Engine type | TVZ-117VM | TVZ-117VMA | TVZ-117VMA |
| Engine power, h.p. | 2x1950 | 2 x 2200 | 2 x 2200 |
| Main rotor diameter, m | 17, 2 | 17, 2 | 17, 2 |
| Empty helicopter weight, kg | 7900 | 8095 | 8660 |
| Takeoff weight, kg: | |||
| normal | 10 200 | 10 400 | 11 000 |
| maximum | 11 200 | 11 500 | 12 100 |
| Combat load mass, kg: | 2300 | 2300 | 2300 |
| Flight speed, km / h: | |||
| maximum | 300 | 300 | 305 |
| cruising | 270 | 265 | 270 |
| Static ceiling | |||
| excluding the influence of the earth, m | 3470 | 3600 | 3600 |
| Dynamic ceiling, m | 5700 | 5800 | 5700 |
| Practical flight range, km | 435 | 460 | 500 |
| Ferry range, km | 1100 | 1100 | 1100 |
| '' In the radio equipment compartment | |||
Landing approach of two serial Mi-28N
Energetic landing approach of the Mi-28N after eight high-precision ATGM launches
