The first is the fuel compartment with the minimum allowable level of armor protection against the most common anti-tank weapons (protection level = 700 and 1000 mm against APFSDS and CE). Damage to this compartment, divided by longitudinal partitions, and partial loss of fuel in battle will not lead to the loss of combat capability by the tank.
Behind the fuel compartment there is a compartment of the service systems of the engine compartment (consists of 2 4TD engines), and above it is the compartment of the main armament. These compartments have a higher level of protection, since the failure of the engine or gun significantly reduces the combat capabilities of the tank. Fuel compartment located in the front of the hull serves as a protective “screen” for the engine compartment and increases its survivability. The power plant includes 2 identical engines (a specially designed compact 4TD installation was planned in the future, 5TDF were used on the test rig). Transmission with hydrostatic drive allows to adjust the amount of power transmitted to each track. This allows:
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Use engines of moderate power (800-1000 hp) with high power of the power plant as a whole;
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Provides mobility in case of combat damage to one of the engines;
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Reduce fuel travel costs by using one of the engines or both, depending on the road conditions.
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The forward and backward speeds are similar – more than 75 km/h , which significantly increases the survival rate of the tank in battle.
Then situated the compartment of the automatic loader with ammunition that has a higher level of protection and shielded from frontal fire by three previous compartments. And above it the compartment of the main armament is situated. The defeat of that compartment may cause a loss of tank firepower, as well as it could lead to the detonation of charges with severe consequences. To neutralize the high pressures resulting from detonation of charges in the “blow off plates” are installed in the bottom of the compartment acting as a safety valve (the first variant of design had “blow off plates” in the roof).
The length of the autoloader compartment provides for the accommodation of the unitary rounds (L=1400 mm) and allows to simplify the kinematics of the feeding and chambering of ammunition into the breech of the gun. In the first embodiment, the layout of the tank rounds in autoloader were located in the conveyors vertically (32 shots), with a centered expenditure mechanism with 4 rounds traversing in vertical axis, in the final design – horizontal placement.
Final design of future soviet tank (corresponds to variant described in 1991 E. A. Molotov’s article in
Armament 152 mm gun 2A73, automatic loader with two horizontal conveyors.
Additional armament is a 30 mm grenade launcher on the rear turret and two 2×7.62 mm TKB-666 twin-barrel machine guns.
Along the perimeter of the tank and in the pits between the sides of the crew compartment, 26 mortars APS “Shtandart” are located providing 360° protection as well as protection against attacks from above.
New variant of the tank differed from the initial (see wooden model) by the scheme of armor protection, automatic loader and caterpillar tracks (4+2 road wheels).
Placement of compartments of the tank “ 490” . Final design variant published in VBTT. №7. 1991, the last publication before death of of E. A. Morozov.
In this design variant much attention is paid to protection against ammunition attacking from above.
1 - fuel compartment;
2 - a compartment of systems of the engine compartment;
3 - main armament compartment;
4 - automatic loader compartment;
5 - crew compartment.
The last in the rear of the tank the compartment of crew is situated. The crew is in a comfortable position with the ergonomic requirements (WC, heating, air conditioning, cooking). On the roof, the second tower is placed with complex electron-optical means for 360° targets search and use primary and secondary weapons.
This arrangement ensures that the differentiation of protection level and survivability of the individual components of the tank in accordance with their importance.
An interesting design feature is the use of the cannon barrel as a tube of a deep fording equipment OPVT (it has 4.6 m height at the maximum elevation to the rear at 30° elevation).
Firepower
Although the tank is a versatile machine, capable of hitting a variety of objectives, its main purpose (in accordance with the concept of main tank) – the fight against highly protected targets (MBTs). The necessity of its solution determines the “shape” and composition of tank weapons complex, type and characteristics of the primary weapon. This concept also remains in our time.
The main armament of the final version of the tank consisted of a 152 mm gun 2А73 with a fully automated ammunition of the 32 unitary rounds are located in two lines. Each conveyor had its own system of ramming. Although the turret had a 360° rotation its angles of elevation/declination of the gun relative to the horizon were -5°, +10° only in the range of directional angles less than ±45°. This disadvantage was compensated for by applying a controlled hydropneumatic suspension that by changing the trim of the machine allows to increase the angles pointing guns in the vertical plane.
At the same time, significantly increased the intenseness of the battlefield with manpower armed with anti-tank weapons – RPG, ATGM etc. High emphasis was provided to such targets in the design of Kharkov ’s tank of the 21st century. Additional weapons included two 2-barrel 7.62 mm machinegun TKB-666 (designed by TsKIB SOO) located on both sides of the aft end of the weapons block, with an independent targeting in vertical axis. Elevation angles (+45°) allows to hit the targets located on the upper floors of buildings and in mountainous terrain. Ready ammunition for each gun was 1500 rounds. On the second turret located above the crew capsule 30 mm automatic grenade launcher was placed with aiming angles 360° in horizontal and -10°, +45° in vertical axis.
Especially laconical was the design of FCS. Sighting systems were built in the form of a separate imaging module and the laser rangefinder located to the right (along the tank) in the gun mask. The TV module and channel for guided projectile [GLATGM] was located on the left. Panoramic sight with the optical channel was located on the second turret, the image was transferred to both the commander-gunner and the driver. Day/night TV panoramic sight was placed on automatic grenade launcher cradle on the rear turret.
Modular thermal and TV sights in the gun mask provided the space to put an already developed and produced in the 80-s devices, for example 1ПН71 1ПН126 “Argus” and others, with their large dimensions, the actuators for elevation and azimuth is not required, since sights were stabilized with a cannon [at the same time fully stabilized panoramic sight remained for targeting and observation while the cannon was in process of loading]. Additional accuracy was achieved thanks to the “active” suspension, reduced the load on the weapon stabilizer.
An interesting feature of the design is the use of a gun barrel as a pipe for air intake of deep-fording equipoment (height of 4.6 m with a maximum elevation at the rear of 30 °).
On the frontal part of the hull, as well as on the fences and shelves, front-facing cameras were installed. The rear view camera was installed in the central part of the tank stern.
On the sides of the turret mortars “Cloud” [Tucha] system - 12 pcs were installed.
Above the crew compartment was located the second turret with additional armament, panoramic sight with a visual channel and day-night television sight, mounted on the same cradle as an automatic grenade launcher.
View of the tank rear - the second turret with blocks of dynamic protection and additional weapons. Maximum angle of elevation of the gun is shown.
Mortars of “Standard” APS in the stern and sides of the crew compartment. In the aft compartment of the crew with two hatches, the driver’s hatch is equipped with a viewing port for driving while on march (stern ahead).
The limitations of the design includes insufficient declination angles of the gun on sides and the rear of the hull.
The problem of mass production of compact tank sights with a thermal imaging channel could not be solved for decades after the collapse of the USSR . At the moment, the problem is solved by purchasing and licensed production of foreign components (in the Russian Federation ). The level of technology development in the USSR and the Russian Federation reflects the 1P126 device, adopted in 2005. It is difficult to imagine a variant of the “alternative history” of the development of technical vision systems in the USSR , if it had not collapsed, but hope for compactness and high characteristics that would allow to pass up optical channel would be unfounded.
An example of the image on the monitor screen of “Argus” (level of 1990-s). It was premature to refuse from the visual channel.
The all-round view from the tank was planned to be implemented with the help of front-view cameras located on the upper frontal part of the front section of the hull and on the futon shelves, as well as the rear-view cameras located in the center of the stern of the hull. The crew also had prism observation devices with image output over the eyepieces of the panoramic sight.
Protection
04.04.74. Proskuryakov (VNIITM): - Protection should be differentiated and provide a firing angle of ± 25///35 degrees. Types of protection: armor, active protection and disguise. Armor must be significantly raised compared to the products “225” and “226”. It is necessary to provide protection from a 120-mm NATO projectile with an increased initial velocity. Without armor we won’t have a tank. Protection is not decided by the LOS thickness, but by new solutions.
Maneuverability should be enhanced by hydromechanical transmission. Isakov is doing it now with VNIITransmash for a 1500 hp engine. This should increase the average speeds, reduce acceleration time, increase controllability, smoothly change the turning radius of the tank, and ensure maximum reversing speed.
The tank design solutions of the 21st century paid key attention to ensuring the protection of tank components in accordance with their contribution to combat effectiveness. If the first (fuel) compartment had a frontal counter-missile protection at the level specified by the tactical-technical requirements, then the last compartment (of the crew) would be practically protected 2-2.5 times higher. Since the creation of projectiles with such a level of armor penetration is impossible in the foreseeable future, this design scheme makes it possible to ensure a high probability of a tank survival in battle with a minimum mass of armor.
Scheme of the tank (in plan) with sequentially placed compartments:
1 – front hull armmor; 2 - fuel compartment; 3 - fuel compartment cross wall;
4 - engine compartment; 5 - cross wall; 6 - combat compartment; 7 – ammo compartment partitions; 8 - compartments of ammunition; 9 - crew compartment cross wall; 10 - crew compartment; 11 - firing angle of the most powerful attacking means α
In the early version of the development of the project, the protection of the upper part of the nose assembly of the hull included a plate of steel 80 mm thick set at an angle of 60°. A removable package (170 mm/60°) with tandem-installed active protection elements was installed on the plate, which were separated by a 50 mm steel plate. In its idea, such protection was similar to the “Duplet” ERA module installed nowadays on the “Oplot” tank.
Armor protection of the turret was a combined structure with spaced apart (armor), combined with active [reactive] elements (front and side) armor.
The equivalent of protection from the upper hemisphere was 180…200 from explosively formed projectiles (EFP) and 600 from cumulative ammunition (CE). The only weak point of the tank was top of the the turret in its central part, where the protection was 50 mm (5°). However, even in the event of the destruction of this section by cumulative ammunition or EFP, only one of the engines could be put out of action.
The roof of the ammunition compartment represented a combined structure with active elements and multi-layered armor; in the final version, the “ejection plates” were made in the bottom to reduce the weakened protection zones from above.
The outer and central parts in the protective structures of the hull and the turret were made of high-hardness steel, the inner parts were of medium-hardness steel. This made it possible to reduce the formation of a fragmentation flow when the penetrating elements were broken through.
The final variant of the design of a 21-st century tank had combined armor (steel + filler + steel + ERA) located at an angle of 80° along all frontal part of the hull, this served both as protection against projectiles attacking from above.
a - longitudinal section; b - plan view with the turret and the hull roof removed; 1 - cannon; 2 - turret; 3 - turret ring race; 4 - cover of the automatic loader; 5 - crew compartment; 6 - crew stern hatches; 7 - loader compartment; 8 - engine compartment; 9 - fuel compartment; 10 - tank hull; 11, 16 - engines; 12, 15, 19, 20 - side gearboxes for transmitting power to the driving wheels of the front and rear contours; 13, 14, 18, 21 - the driving wheels of the front and rear contours; 17, 22 - tracks front and rear contours.
The protection arrangement included the layer of active elements of the protection scheme combined with a longitudinal compression of the filler (steel + reactive tile + filler) that improves protection up to ~40%. The total LOS was 260 mm at 80°. the Structure provided protection from munitions attacking horizontally, but also protection from ammunition attacking from above.
The compartments of the tank was separated by 20 mm bulkhead for fuel compartment and systems of the engine compartment. 20 mm bulkhead between 1 and 2 engines. Bulkhead with a size of 50 mm was installed in front of compartment of ammunition and crew. In the bottom of the crew capsule an escape hatch was provided, which also could be transformed in sanitary unit. Protection at the bottom of the hull was also differentiated 20, 50 and 100 mm (combined) in the areas of fuel and engine compartment; compartment of ammunition; crew capsule.
Mobility
Located in the middle part of the tank, in front of the crew compartment, the power plant provided additional protection for the crew. The four-tracked undercarriage, due to such a layout scheme, significantly increases the survivability of the tank during mine explosions. Increased survivability also contributes to the separate execution of systems serving each engine.
On the basis of a tank with two engines a family of vehicles using one or two engine can be created, depending on the type and purpose of the machine, on the mass and power consumed by the equipment (IFV, missile tank and so on).
Requirements for mobility of tanks are constantly increasing. It is assumed that the average speed of the tank of the near future when driving on dry dirt roads should be 50…55 km/h. To achieve this speed, the specific power of the tank must be at least 21…23 kW /t, and the maximum speed provided by the speed range of the transmission 80…90 km / h.
Overcoming natural and artificial obstacles, making passages using attached and built-in equipment requires an additional increase in the power of the power plant.
One of the important measures to protect the tank is to increase mobility for the purpose of effective maneuvering under fire (including reversing, without exposing the vulnerable rear of the tank). Studies show that due to defensive maneuvering on the battlefield, the probability of hitting a tank decreases by 2-4 times, security increases by 1,5-2 times. This applies in particular to protection against guided missiles. Thus, to increase the mobility of a tank with a predicted weight (over 54 tons), a power unit with a capacity of 1320…1470 kW is required.
High dynamic qualities of the tanks in the capacity range combined with good fuel economy under light loads, it is possible to provide motors with two power levels (4TD – 800 and 1000 HP).
The second, lower, power level required for economical operation of the tank with limited speed and relatively light traffic conditions.
For future tanks can be applied engine compartament with two identical engines, located in the middle part of the tank, with transmission with hydrostatic drive of the turning mechanism. Reverse mechanism enables movement of the front and rear move at the same speed.
Marching movement of the tank in column was expected to perform stern-foremost. In the aft hatch of the driver there was a window and TV system for rear view. The chair was done turning 360°.
Chassis test rig of object “ 490” .
Chassis layout of the tank with a power plant with two engines and 4-track undercarriage:
1 - cab, 2 - front; 3 - the back.
The layout was made on the basis of two T-64A tanks with a 5TDF engines. The tanks cut out the upper part of the body with fighting compartments; control compartment and the engine-transmission are connected in a single module. Connected by the stern parts, they form a two-engine undercarriage model with four caterpillar contours.
The mass of the test rig was 35.6 tons. The side gearboxes of the rear part of the model are modernized so that they provide movement at a speed corresponding to the speed of movement of the front part. In front of the vehicle engine management system was installed.
Scheme chassis with a engine compartment with two engines:
1 - driving wheel; 2 - a steering wheel; 3 – final drive; 4 – hydrostatic-mechanical transmission; 5 - reduction gear of hydrostatic drive; 6 - reverse with reduction gear; 7 - engine; 8 - hydrostatic drive of the rotation mechanism
Each of the engines provides a power of 590…660 kW·with a short-term boost to 740 kW. Thus, the total capacity of the power plant reaches…1180 1320 kW, and power density of the layout 33…37 kW/t. This will ensure that the specific capacity of the tank is equal to 29 kW/t.
With this design, obviating the need for long-term development of a new tank engine of high power. The proposed scheme increases durability and fuel efficiency of the power plant due to the efficient power utilization of one or both engines. See Tank power unit with two engines.
The chassis of the tank was developed basing on Object “ 219” [T-80] elements (rollers and so on).
Variants of the tank were studied with ejection, combined (ejection+fan) and fan cooling.
For future tanks of the 21-st century was supposed to use the engine 4TD, based on the design and techniques used on a serial produced engine 6TD-2. Installation of two engines 6TD-2 had excess capacity, in addition to reduce the size of the optimal was to install two engines of smaller size. Creating a new engine 4TD in the 90-s was not risky in the technical aspects and lack of problematic issues. 4TD developed capacity in nominal and forced modes 800 and 1000 h/p.
Many years it took once clashed on the territory of the USSR tanks developers in order to come to a conclusion –
“As a result of our collaboration with the Kharkiv side, it was agreed to take the decision for further development of common procurement with the Kharkiv engine 6TD-2, but with supporting systems created in Tagil”. E. B. Vavilonsky (head of Department of power plants, the leading designer Department design a new UKBTM).
Another confirmation of the correct direction of the selected E. A. Morozov was a demonstration in October 2018 at the AUSA Symposium of the project of the prospective engine for armored fighting vehicles of the United States , created in the framework of the program “Advanced Combat Engine”. They were the American equivalent 4TD created with the use of modern technology level.
Advantages of the E. A. Morozov’s project of the tank of the 21st century
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The maximum possible protection for the crew within the weight restrictions ~55 tons.
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The location of the crew in the least susceptible to fire area at the rear of the tank in a highly secure capsule.
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Simple design of sighting complexes corresponding to the level of development of science and technology in the near future. The presence of a visual channel panoramic sight with an overview from the highest point of the tank.
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A simple schematic of an automatic loader without any restrictions on the length of the shot L=1400 (the active part of the APFSDS up to 1300 mm ) with fully automated of ammunition. All ammunition main armament is fully mechanized and located in an autoloader with a simple trajectory and kinematics of the delivery of the shot into the breech of the gun.
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The possibility of movement forward and reverse at the same speed ( 75 km/h ).
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The ease of creating a family of vehicles with 1 or 2 engines and a convenient placement of troops and payload. For example, highly protected infantry fighting vehicles. A significant effect on the appearance of the tank, along with the fundamental solutions of the basic units and systems, can provide: reduction of the functional tasks of tanks in battle; the fixture to the tank design as a basic machine for a family of armored vehicles and to the conditions of mass production; the need to preserve the possibility of further improvement during the life cycle of the machine.
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With the aim of increasing the survivability of the chassis it has a 4-bypass drive each valve. This gives the opportunity to the tank when you break one of the lines (and even two on different sides) not to lose mobility.
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Maximum protection of the crew capsule from the entire set of attack weapons, including chemical, bacteriological and radiation exposure, comfort in the crew compartment (the presence of sanitary devices, and the devices for cooking and air conditioning). Co-location of the crew radically solves the issues of mutual assistance and interchangeability, simplifies internal communication and duplication of functions of the tank.
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Maximum mine protection of the tank and crew members;
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Engines of the tank have the ability to work in two modes:
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the maximum power when driving and heavy traffic conditions and in battle;
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in economic mode (~50% - when driving on good dirt roads and paved roads. Both modes should be equivalent to efficiency, providing the minimum specific fuel consumption. This is the most radical way of increasing tank driving distance with a limited amount of fuel it carries.
- Replacement torsion bars with hydropneumatic suspension, in addition to the main goal - increase the average speeds due to the improved smoothness that gives adjustable clearance of the tank, which increases its cross-country capacity and survivability in combat.
In addition, controlled hydropneumatic suspension by changing the clearance of the machine allows to increase the angles of cannon laying in the vertical plane. Thus, the introduction of only one system increases the rates of mobility (direct effect), protection and firepower (side effect).