Scientific Council P. O. Box A-7701
In the previous articles in the series, it was about the theoretical calculations of domestic engineers regarding the vulnerability of armored vehicles of NATO countries. The history of the development of tank building in the Soviet Union would be incomplete without mentioning the scientific work unfolding in specialized institutes. One of these was the Leningrad All-Union Scientific Research Institute of Transport Engineering, or VNIITransmash, at various times engaged in the development of machines of the T-64 and T-80 families. In addition, in the secret research institute, which was called "post office (mail) box A-7701", they worked on domestic lunar rovers. "Bulletin of armored vehicles", which eventually became a specialized publication of VNIITransmash, regularly published information on the defense of dissertations. The first brief materials on this topic date back to 1973 and make it possible to assess the main directions of scientific work in the head tank research institute. It is interesting that in one year only 8 dissertations were defended for the degree of candidate of technical sciences. In subsequent years, the number of defended scientific papers on the tank theme steadily increased.
Among the works there are survey studies on the issues of quantitative assessment of the technical level of modern armored vehicles and highly specialized dissertations. For example, about the development of a method for optimizing the parameters of a cutting tool, which makes it possible to identify reserves for increasing the fracture strength of the transmission teeth of a medium tank. In 1974, preparations were underway for serial production of T-80 tanks, and VNIITransmash engineers defended their dissertations in parallel. This is how a study appeared on the development of a semi-automatic hydraulic control system for a tank transmission with onboard gearboxes and a gas turbine engine. A year later, the defense of the work on the topic: "Investigation of the performance and parameters of a gas turbine engine in the system of a tank power plant at high dust content" took place. This is largely a topical study of a problem that has not yet been fully resolved. Another work on this topic was the research and development of direct-flow cyclones for air cleaners of tank gas turbine plants.
A separate direction was work to improve the firing accuracy of tank guns. One of the theses substantiates the choice of preferred directions for reducing repetitive errors associated with increasing the accuracy and stability of the battle of tank guns. The developed fire control system takes into account the deviations of the firing conditions from normal ones, as well as the parameters of the target and tank movement. Also, within the framework of the direction, work was carried out to develop target tracking systems and improve guidance accuracy.
In September 1974, she successfully defended two theses on improving the survivability of a tank on the battlefield. In one of them, the issue of improving armor and internal equipment was considered, taking into account the design features of the tank and the armored action of anti-tank ammunition with and without penetration. In the second work, the stability of the hulls of armored vehicles was modeled when exposed to a shock wave of a nuclear explosion.
Finally, the dissertation councils reflected the long-term work of VNIITransmash dedicated to the lunar program of the Soviet Union. In 1974, the calculations of the operational load of the chassis wheels when a transport vehicle moved across the rough terrain of the Moon and planets received their logical conclusion. In this work, the author chose the optimal suspension systems that ensure satisfactory contact of the wheels with the ground at maximum speeds. The topic of a scientific work defended a year later looks even more fantastic: "Investigation of the longitudinal dynamic stability of planetary vehicles". The planetary transports were Lunokhod-1 and Lunokhod-2.
Korean-Cuban heritage
Scientific work in the tank industry took place not only at VNIITransmash, but also at many other institutes. However, the employees of military unit No. 68054, or the Research Institute "Polygon" in Kubinka, contacted directly with samples of foreign equipment. In the post-war period, one of the first armored vehicles that underwent detailed study was the American M19A1 anti-aircraft self-propelled gun, which had no direct analogues in the Soviet Army at that time. The vehicle was based on the chassis of a light tank M-24, armed with two coaxial 40-mm M1 "Bofors" cannons and an auxiliary 12, 7-mm machine gun "Browning". The anti-aircraft gun did not have time to fight in World War II, but on the Korean Peninsula it participated in hostilities and even was captured, and from there to Kubinka. Moreover, together with the instruction manual. In one of the issues of the Bulletin of Tank Industry, Captain-Engineer IP Myrzak presented a detailed report on the armament of the M19A1 installation. The critical remarks that were mentioned in the material are interesting. Thus, the author points out that the turret niche covers two boxes of ammunition stowage, as a result of which the “turret” has to be rotated to retrieve the shells. Yes, this is exactly how, in quotation marks, a platform with an open-type fighting compartment is indicated, in which the weapon was placed. In general, the layout flaws reduced the rate of fire of the M19A1 cannons from 25 rounds per minute to 20. The loaders had to bend over the side of the fighting compartment behind the packs of ammunition, and also separately turn the "tower" in order to take the clips located near the cannon barrels. Found a minus and the anti-aircraft sight. Such were the low accuracy due to the eye determination of the speed and course of the target, as well as the inability to conduct aimed fire at diving and pitching aircraft. But the electro-hydraulic control system of the installation when firing at air targets, obviously, made an impression on domestic engineers. The material does not contain a single critical remark on the design, but several pages are devoted to a detailed description of the device.
If in the case of the M19A1, the interest of researchers was attracted by weapons, then in the light tank M-41 Walker Bulldog, the properties of armor and welds came to the fore. Here, experts actually cut the tank with "scalpels" - samples of the lower and upper frontal parts, the rear part of the side and the middle rear part of the hull, the turret cover, as well as the lower rear part with the rear part of the bottom went into work. Of course, the armored vehicle was not completely shredded, but they got an idea of the level of protection. They brought a light tank to the USSR from friendly Cuba ("Fidel's gift") after the battles at Playa Gironi in April 1961, and it is still kept in the Tank Museum. Already in 1962, the Vestnik published a detailed report on the features of the M-41. One of the leading organizations on the topic of research was the Research Institute of Steel: it was here that the armor of a light tank was analyzed. The composition of the steel was investigated by spectral and chemical analysis. It turned out that the armor was predominantly manganese-molybdenum with 0, 10-0, 15% titanium. The authors conclude that this steel composition is typical of American bulletproof armor. In the refrigerating chamber of the TsDMK-30 testing machine, tensile tests of the armor were carried out, pre-cooling the samples to -50 degrees for an hour and a half. Similar experiments were also carried out at a temperature of +20 degrees. The M-41 armor turned out to be high-strength with satisfactory ductility and high impact strength. The authors point out that the steel will resist well with small arms fire without brittle damage.
Considerable interest of domestic researchers was aroused by the welded joints of the armor parts of the tank. It turned out that the Americans use automatic welding, and there are 6-8 mm gaps between the parts. This negatively affects the bullet resistance of the hull and turret, since the seam is much less resistant to shock loads than the main armor.
It is worth noting that the M-41 was not fired at the test site, obviously, saving for other research and the museum. Therefore, the strength of American armor was determined using the curves of the bullet resistance of domestic high hardness armor (in many respects, these steels were similar). In accordance with this, the front of the hull and the turret (except for the rear) were not penetrated by armor-piercing calibers 7, 62 mm, 12, 7 mm and 14, 5 mm from any distance and at any angle. The sides of the hull are penetrated by 14.5-mm bullets only in a limited range of course angles and at relatively short ranges. However, as the authors of the article assure, these calculations can be treated with a certain degree of convention. The most unambiguous conclusion based on the results of working with "Fidel's gift" is a negative assessment of the height of the armored vehicle: for the Soviet engineering school of tank building, 2, 7 meters seemed excessive.
