The introduction of laser rangefinders and ballistic computers on the tank was associated not only with the need to ensure effective firing of artillery shells. At the end of the 60s, attempts were made to create guided weapons for tanks, for which laser rangefinders and ballistic computers were one of the key elements.
The introduction of guided weapons on the M60A2 and T-64B tanks led to the creation of the first MSA and largely stimulated their improvement. On the M60A2 tank, the Shilleila guided weapons did not take root, but contributed to the development of more advanced components of the FCS, which were installed on the tank without guided weapons.
On the T-64B tank, the Cobra guided armament concept using a standard tank cannon and an FCS, which solves the problem of firing both artillery shells and a guided missile, has shown its effectiveness and paved the way for the creation of more advanced artillery and guided armament systems for the tank.
MSA tank M60A2
The first MSA was introduced on the American M60A2 tank (1968). The M21 digital ballistic computer combined sights, an armament stabilizer, a laser rangefinder and input sensors (tank speed, turret position in relation to the tank hull, wind speed and direction, cannon axle roll) into a single system, providing optimal conditions for firing a guided missile, calculated the angles of aiming and lead for artillery shells and entered them into the sights. The characteristics of the barrel bore wear, air temperature and pressure, charge temperature were entered into the TBV manually.
Compared to the M60 tank, the commander, instead of the M17S optical rangefinder sight, installed an AN / WG-2 rangefinder sight with a laser rangefinder, providing an accuracy of measuring the range of up to 10 m, instead of the M17S optical rangefinder sight, and instead of the KhM34 commander's day sight, the M36E1 day / night sight was installed, working in active and passive modes. Instead of the main M31 daytime periscope sight, the gunner installed the M35E1 day / night sight, also operating in active and passive modes, the M105 auxiliary gunner's sight was also preserved. The rest of the observation devices and sights have not undergone any qualitative changes.
The tank was equipped with an armament stabilizer with electro-hydraulic cannon and turret drives. The gunner's and commander's sights were not stabilized and had dependent vertical and horizontal field of view stabilization from the weapon stabilizer, which limited their capabilities.
Instead of a standard tank gun, this modification of the tank was equipped with a short-barreled 152-mm gun for firing guided missiles "Shilleila" with an infrared guidance channel at a range of up to 3000 m. unreliability also did not justify itself. As a result, this modification of the tank was removed from service and on subsequent modifications of the M60 tank they returned to installing a 105 mm cannon without using guided weapons.
The dependent stabilization of the field of view of the sights from the stabilizer of the weapon did not allow to fully realize the advantages of the FCS with TBV, the aiming and lateral lead angles could not be automatically entered into the drives of the gun and turret, and shooting outright on the M60A2 was problematic.
Despite all the shortcomings and problematic issues that could not be solved when creating the FCS of the M60A2 tank, this was the first attempt to link the instruments and fire control systems of the tank into an automated system that measures parameters affecting the accuracy of firing, and the generation of data for firing, which gave a certain impetus in the development of tank MSA.
OMS of the tank "Leopard A4"
On the German tank "Leopard A4" (1974), the concept of building the FCS was taken from the M60A2 tank, the difference was the use of the commander's panoramic sight with independent vertical and horizontal stabilization of the field of view.
On this modification of the Leopard A4 tank, the TEM-1A stereoscopic gunner's sight was replaced by the EMES 12A1 day / night sight with dependent two-plane stabilization of the field of view from the weapon stabilizer, which provides more accurate range measurement with stereoscopic and laser rangefinders and night vision in massive mode. The gunner kept the auxiliary telescopic articulated sight FERO-Z12.
Instead of a panoramic unstabilized sight TRP-2A, the commander had a panoramic sight PERI R12 with independent two-plane stabilization of the field of view, with which it was possible, when coordinated with the longitudinal axis of the gunner's sight, to fire from a cannon using a laser rangefinder and a night channel of the gunner's sight.
The weapon stabilizer with electro-hydraulic drives of the gun and turret was controlled from the gunner's and commander's consoles and ensured the holding of the gun in a given direction.
The central element of the FCS was the FLER-H ballistic computer, which takes into account the meteorological ballistic parameters of firing with a set of sensors, similar to the FCS of the M60A2 tank, and provides automatic calculation of the aiming and lead angles.
The FCS of the Leopard A4 tank had the same drawback as the FCS M60A2, the aiming and lead angles could not be automatically entered into the gun drives due to the lack of independent stabilization of the field of view of the gunner's sight. This was only possible when shooting from the commander's seat through a panoramic sight. The gunner's sight with independent stabilization of the field of view EMES 15 was installed only on the Leopard 2 tank. Many elements of the FCS of the Leopard A4 tank were later used on the Leopard 2 tank.
FCS of the T-64B tank
On Soviet tanks, the first MSA was introduced on the T-64B tank (1973) when creating the Cobra guided weapons with a two-channel guidance system, an optical channel for determining the coordinates of the missile in relation to the aiming line and a radio command channel for missile guidance.
At that time, TsNIIAG (Moscow) was the lead for the tank LMS, which determined the requirements, structure and instrumental composition of the LMS. Under his leadership, the T-64B SUO 1A33 "Ob" was developed and implemented on the T-64B tank, which became the basis for all subsequent fire control systems of Soviet tanks.
In 1974, the tank industry lost the lead on the development of the MSA, TsNIIAG was transferred to the development of control systems for operational-tactical missiles. Central Design Bureau KMZ (Krasnogorsk), which developed only tank sights, had never been involved in the development of systems of this class and had no experience in this matter, was appointed head of the OMS. All this affected the work in this direction, with the actual absence of the head for the OMS, the development of the structure and instrumentation of the next generation systems was carried out in tank design bureaus in Kharkov and Leningrad.
The central unifying element of the FCS 1A33 of the T-64B tank (object 447A) was the 1V517 digital tank ballistic computer developed by MIET (Moscow). TBV combined the gunner's sight, laser rangefinder, weapon stabilizer, guided weapon system and input information sensors into a single automated system. TBV calculated the aiming and lead angles and automatically entered them into the gun and turret drives, greatly simplifying the gunner's work when firing and increasing the accuracy of shooting.
Input information sensors automatically measured the speed of the tank, the angle of the turret in relation to the hull, the angular velocity of the tank and the target, the roll of the axis of the gun trunnions, the speed of the side wind and entered them into the TBV. The charge temperature, gun barrel wear, temperature and air pressure were entered into the TBV manually.
The control system of the first batches of T-64B tanks, produced in 1973, was built on the basis of the gunner's sight 1G21 "Kadr". The head developer of tank sights, TsKB KMZ, began developing the Kadr-1 sight with a laser rangefinder for the LMS 1A33 and was unable to complete the development of such a sight. The groundwork was transferred to the Tochpribor Central Design Bureau (Novosibirsk), which developed the sight and provided samples for testing.
The first batches of tanks had many shortcomings in the Ob control system and the Cobra complex, including the Kadr sight and the laser rangefinder. The "Kadr" sight required improvement due to the imperfection of the stabilization system and the vibration of the field of view, which made it difficult to control the missile, the insufficiently accurate coordinator fixing the position of the missile in relation to the aiming line and the need to cool the laser. For example, to cool the laser, a small tank of alcohol was installed in the tank, connected to the sight with a rubber hose in an armored sheath. In the troops, the lasers began to fail, it turned out that the alcohol was inexplicably evaporating from the tank. Later it was found that the soldiers were bending the hose and using a medical syringe through an armored braid to extract alcohol, this cooling had to be urgently disposed of.
In 1975, Tochpribor Central Design Bureau developed a new sight 1G42 Ob with improved independent stabilization of the field of view vertically and horizontally, a more advanced laser without cooling, and an accurate channel for determining the coordinates of a guided missile. The sight had an optical channel with a smoothly varying magnification of 3, 9 … 9x with a field of view of 20 … 8 degrees, a laser channel and an optical - electronic channel with a coordinator for fixing the position of the rocket in relation to the aiming line. The laser rangefinder provided a range measurement in the range of 500 … 4000 m with an accuracy of 10 m.
Sight 1G42
The MSA included a 2E26M armament stabilizer with electro-hydraulic drives for the gun and turret; the turret drive during modernization was replaced with a drive with an electric machine amplifier.
The night sights and devices of the commander have not fundamentally changed. Next to the gunner's sight 1G42, a modification of the TPN1-49-23 unstabilized gunner's sight was installed, providing a range of vision at night in active mode with an L-4A searchlight up to 1000 m. in passive-active mode and providing a range in passive mode of 550 m and in active mode of 1300 m. The commander still has an upgraded day-night sight TKN-3V with a night vision range in active mode up to 400 m and an anti-aircraft gun remotely controlled with the commander's hatch closed with a sight PZU-5. Duplicate firing from the cannon from the commander's seat was impossible.
At the final stage of testing the Ob control system and the Cobra complex on the T-64B tank in 1976, the tower of one of the tanks was installed on the hull of the T-80 tank, which was tested and in 1978 was put into service as the T-80B tank …
It should be noted that the contribution of the CDB KMZ to the FCS "Ob" was only in the creation of a shot resolution block 1G43, which formed the shot resolution zone when coordinating the aiming line and the gun. For these purposes, a separate unit was developed, although the TBV could easily solve this problem with practically no additional hardware costs when introducing aiming and lead angles into the arms of the weapon stabilizer. This "misunderstanding" is still being produced and installed on tanks.
The development of the OMS "Ob" was a landmark in the Soviet tank building, more advanced OMSs on subsequent modifications of the T-64 and T-80 tanks were created on the basis of this system and the sights for them were developed by the Central Design Bureau "Tochpribor". CDB KMZ was only able to modernize and develop sights TPD-K1 and 1A40 with laser rangefinders based on the TPD-2-49 sight with a one-plane stabilization system of the field of view for simplified OMS of the T-72 family of tanks.
At this stage, the FCS of the T-64B tank, due to the installation of a sight with independent stabilization of the field of view and the introduction of effective guided weapons that do not deteriorate the characteristics of artillery weapons, was devoid of the disadvantages of the FCS of the M60A2 and Leopard A4 tanks and made it possible to significantly increase the effectiveness of firing from the tank. But the commander's instruments remained imperfect and were in no way tied into a single complex with the gunner's instruments.
At the same time, the M60A2 and Leopard A4 tanks had next-generation night vision devices and sights, the gunner had a backup sight on the gun for firing in case of failure of the main sights, and the commander had the ability to duplicate fire from the gun instead of the gunner. In addition, a panoramic commander's sight stabilized in two planes with a sight head rotating 360 degrees has already been introduced on the Leopard A4.
