Since the end of the eighties, the Kharkov Design Bureau for Mechanical Engineering (KMDB) has been working on various options for promising tanks. One of the most interesting and daring developments of that time was the "Object 490". This project proposed the construction of a tank of an unusual appearance, characteristic layout and special characteristics. Consider this machine from the point of view of measures to increase the level of protection.
Tank theory
In the course of R&D on the topic "490", several options for the architecture of a promising MBT were worked out - both classical and several new ones. High performance was promised by the new layout with the division of the tank into several compartments for different purposes. In this case, the body was made in the form of a horizontal wedge with an inclined roof. It was proposed to divide a single tracked propeller into two pairs of tracks.
The tank of the new architecture was supposed to have an increased level of resistance to all major threats. Fighting qualities were planned to be improved by means of an automated fighting compartment and guns of increased caliber. The new unusual chassis allowed for increased mobility.
Layout protection
The main feature of the "Object 490" was an unusual layout with the division of the hull and turret into compartments with different equipment and tasks. The proposed variant of the placement of the units in itself made it possible to cover the most important elements of the tank, as well as to protect the crew from the main threats.
The bow compartment, it was proposed to give for the placement of a large fuel tank, divided by longitudinal walls. The armor and tank were supposed to cover the other compartments, protecting them from the main threats from the bow corners. The design of the tank in the event of a defeat allowed for the loss of some of the fuel, but made it possible to maintain mobility and combat effectiveness.
The engine compartment was located behind the fuel compartment and under the turret. With this arrangement, the engine and transmission were covered with armor, a tank and a turret. All this reduced to a minimum the likelihood of injury and complete loss of mobility.
The fighting compartment was divided into two parts. The first, including armament and a part of automatic loading, was arranged in the form of a gun-carriage tower on the roof of the hull. The mechanized stowage of ammunition and the means of supplying shots to the turret were placed in their own compartment in the hull, behind the MTO. Like the engine, the styling had the greatest possible protection due to several factors.
For the crew, they provided their own capsule compartment in the rear of the hull. This placement of the capsule virtually eliminated the defeat of the crew from the front corners. When an anti-tank weapon attacked the tank from the upper hemisphere, the probability of hitting the capsule was also reduced due to its reduced area. The habitable volume was equipped with an anti-nuclear protection system.
Thus, the layout of the "Object 490" has been optimized from the point of view. mutual arrangement of units and taking into account the most probable threats. When attacking from the main directions, from the front and from above, the compartments and assemblies covered each other, providing the best protection for the most important ones. In addition, it provided powerful protection for the crew.
Armor protection
Reservation of "Object 490" was worked out taking into account protection against armor-piercing shells of foreign 120-mm guns. It was proposed to use combined and homogeneous booking, as well as dynamic protection units.
The upper frontal part was made at the same time with the inclined roof of the body in the form of a combined barrier with the possibility of mounting a remote sensing device. Also, in the composition of the forehead, steel armor with a remote control was used, covering the fuel compartment. An 81 ° slope roof had the maximum possible reduced thickness and an appropriate level of protection. With all its advantages, such a hull roof seriously complicated the development of a turret ring.
Crew protection was provided by circular armor of the aft compartment and combined protection from above. The aft wall of the capsule had openings for hatches.
The frontal part of the tower was also supposed to receive a combined frontal barrier. The roof and sides were made of homogeneous armor of limited thickness. So, the roof of the tower with a slight forward inclination had a thickness of only 50 mm - but a significant reduced thickness when fired from the front.
It was proposed to use the bottom of the hull with differential armor, incl. with combined areas. Under the most important compartments and units there was a 100 mm bottom, on others - from 20 mm.
The main elements of the armored hull were proposed to be performed in the form of a combined protection of two sheets of steel with a filler between them. To reduce the armor action of the fragments, it was proposed to combine steel grades. The outer and middle armor elements were required to be made of high hardness steel, while the inner ones were of medium hardness.
The metal armor was planned to be supplemented with dynamic protection. In the eighties, the Research Institute of Steel developed new types of similar products, and with their help it was possible to strengthen the armor of tanks. The use of armor and remote sensing made it possible not only to protect the tank from modern threats, but also to provide a reserve for the future.
Mobility protection
Speed and maneuver are one of the components of MBT survivability on the battlefield. In the 490 project, these factors were not only taken into account, but also were among the key ones. It was with them that the creation of a special power plant based on two power units, working with two tracked propellers, was associated.
With an estimated weight of up to 52-54 tons, "Object 490" needed a power plant with a total capacity of up to 1450-1470 hp. The presence of two engines and two transmissions not only ensured the operation of four tracks, but also increased survivability to some extent. The defeat of one of the power units did not deprive the tank of mobility.
Protection characteristics
According to calculations, the frontal projection of "Object 490" really could withstand the impact of existing foreign armor-piercing shells. The upper projection of the hull had a cumulative ammunition resistance equivalent to 600 mm of homogeneous armor. At the same time, the roof of the tower was much less durable.
However, the defeat of the tower could not have fatal consequences in all cases. In particular, a single penetration of armor threatened only with the incapacitation of individual devices in the fighting compartment and, in the worst case, only one block of the power plant. After such a defeat, the tank retained mobility and, possibly, combat capability. It is important that the chances of the crew to survive and maintain health increased many times over.
Thus, at least at the level of theory, a promising tank had significant advantages over the available equipment in the field of protection and survivability. "Object 490" could engage in battle with modern and promising enemy MBT and be subject to minimal risk. All this, to a certain extent, was supposed to facilitate the fight against enemy armored vehicles and the solution of combat missions.
At the layout stage
The development of "Object 490" with the characteristic features of protection was completed at the end of the eighties. By this time, KMDB had produced a number of models and prototypes to test various ideas and solutions. The result of such work was the construction of a full-size mock-up of MBT "490". However, the project did not progress further.
At that time, the political and economic situation did not contribute to the further development of the project and the launch of the series. Due to the collapse of the USSR, the prospects for many projects have become dim. Further events actually put an end to the "Object 490" and other developments of the KMDB. The army of independent Ukraine was not interested in promising domestic tanks, and there were no other potential customers.
Long-term and important research and development work gave real results in the form of a mass of developments on various topics, but most of them were never used in practice. Nevertheless, the main decisions of the project "490" are still of great interest, both from a technical and a historical point of view.
