In connection with the adoption in the fall of 1943 of the new heavy tank IS for the Red Army and the withdrawal from production of the KV-1S, it became necessary to create a heavy self-propelled gun on the basis of a new heavy tank. Decree of the State Defense Committee No. 4043ss of September 4, 1943 ordered the Experimental Plant No. 100 in Chelyabinsk, together with the technical department of the Main Armored Directorate of the Red Army, to design, manufacture and test the IS-152 artillery self-propelled gun based on the IS tank until November 1, 1943.
During development, the installation received the factory designation "object 241". G. N. Moskvin was appointed the leading designer. The prototype was made in October. For several weeks, the ACS was tested at the NIBT Polygon in Kubinka and ANIOP in Gorokhovets. On November 6, 1943, by a GKO decree, the new vehicle was accepted into service under the designation ISU-152, and in December its serial production began.
The layout of the ISU-152 did not differ in fundamental innovations. The conning tower, made of rolled armor plates, was installed in the front of the hull, combining the control compartment and the combat compartment into one volume. The engine compartment was located in the rear of the hull. The nose part of the hull on the installations of the first releases was made cast, on the machines of the last releases it had a welded structure. The number and placement of crew members were the same as that of the SU-152. If the crew consisted of four people, then the loader's duties were performed by the lock. For the landing of the crew in the roof of the wheelhouse there were two round hatches in the front and one rectangular in the aft. All hatches were closed with double-leaf covers, in the upper doors of which MK-4 observation devices were installed. In the frontal leaf of the cabin there was an inspection hatch for the driver, which was closed by an armored stopper with a glass block and a viewing slot.
The conning tower itself has not undergone fundamental changes. Due to the smaller width of the IS tank, in comparison with the KB, it was necessary to reduce the inclination of the side sheets from 25 ° to 15 ° to the vertical, and eliminate the inclination of the stern sheet altogether. At the same time, the thickness of the armor increased from 75 to 90 mm at the frontal leaf of the casemate and from 60 to 75 mm at the side ones. The gun mask had a thickness of 60 mm, and was subsequently increased to 100 mm.
The deckhouse roof consisted of two parts. The front part of the roof was welded to the front, cheekbone and side plates. In it, in addition to two round hatches, a hole was made to install the fan of the fighting compartment (in the middle), which was closed from the outside with an armored cap, and a hatch was also provided for accessing the filler neck of the left front fuel tank (on the left) and an antenna input hole (on the right). The rear roof sheet was removable and bolted. It should be noted that the installation of an exhaust fan became a significant advantage of the ISU-152, compared to the SU-152, in which there was no forced ventilation at all and the crew members sometimes fainted from the accumulated powder gases during the battle.
One of the first serial ISU-152 at the test site. 1944 year.
However, according to the recollections of the self-propelled gunners, the ventilation left much to be desired on the new car.
the best - when the bolt was opened after the shot, an avalanche of thick powder smoke, similar to sour cream, streamed from the gun barrel and slowly spread across the floor of the fighting compartment.
The roof over the engine compartment consisted of a removable sheet over the engine, nets over the air intake windows to the engine, and armored grilles over the louvers. The removable sheet had a hatch for access to the engine components and assemblies, which was closed by a hinged cover. At the rear of the sheet there were two hatches for access to the fuel and oil tank filler necks. The middle rear hull sheet in the combat position was screwed in with bolts; during repairs, it could be folded back on hinges. For access to the transmission units, it had two round hatches, which were closed by hinged armored covers. The bottom of the hull was welded from three armor plates and had hatches and holes that were closed by armor covers and plugs.
152-mm howitzer-gun ML-20S mod. 1937/43 was mounted in a cast frame, which played the role of the upper machine tool, and was protected by a cast armor mask borrowed from the SU-152. The swinging part of the self-propelled howitzer-gun had minor differences compared to the field one: a folding tray was installed to facilitate loading and additional thrust to the trigger mechanism, the handles of the flywheels of the lifting and turning mechanisms were at the gunner's left in the direction of the vehicle, the trunnions were moved forward for natural balancing … Vertical guidance angles ranged from -3 ° to + 20 °, horizontal - in the 10 ° sector. The height of the line of fire was 1800 mm. For direct fire, the ST-10 telescopic sight with a semi-independent line of sight was used; for firing from closed firing positions, a Hertz panorama with an extension cord was used, the lens of which exited the wheelhouse through the open left upper hatch. When shooting at night, the sight and panorama scales, as well as the aiming and gun arrows, were illuminated by electric bulbs of the Luch 5 device. The firing range of direct fire was 3800 m, the highest - 6200 m. The rate of fire was 2 - 3 rds / min. The gun had electrical and mechanical (manual) triggering. The electric trigger was located on the flywheel handle of the lifting mechanism. On the guns of the first releases, a mechanical (manual) escapement was used. The lifting and turning mechanisms of the sector type were attached to brackets to the left cheek of the frame.
The ammunition load was 21 rounds of separate cartridge case loading with BR-540 armor-piercing tracer shells with an MD-7 bottom fuse with a tracer, high-explosive fragmentation cannon and steel howitzer grenades OF-540 and OF-530 with RGM-2 fuses (or -1), O-530A steel cast iron fragmentation howitzer grenades, which were located in the fighting compartment. armor-piercing tracer shells were in the armored cabin niche on the left side of the wheelhouse in special frames, high-explosive fragmentation grenades - in the same place, cartridges with warheads in the armored cabin niche in special frames and in a clamp packing. Some of the shells with warheads were placed on the bottom under the gun. The shots were equipped with the following charges: No. 1 variable Zh11-545, reduced variable Zh-545U or ZhP-545U, full variable ZhN-545 or Zh-545 without one equilibrium beam and a special ZhN-545B or Zh-545B for an armor-piercing tracer. The initial velocity of an armor-piercing projectile with a mass of 48, 78 kg was 600 m / s, a high-explosive fragmentation projectile with a mass of 43, 56 kg - 600 m / s. An armor-piercing projectile at a distance of 1000 m pierced armor with a thickness of 123 mm.
Since October 1944, an anti-aircraft turret with a 12, 7-mm DShK machine gun mod. 1938 The ammunition for the machine gun was 250 rounds. In addition, two PPSh submachine guns (later - PPS) with 1491 rounds of ammunition and 20 F-1 hand grenades were stored in the fighting compartment.
The power plant and transmission were borrowed from the IS-1 (IS-2) tank. The ISU-152 was equipped with a 12-cylinder four-stroke diesel engine V-2IS (V-2-10) with a capacity of 520 hp. at 2000 rpm. The cylinders were V-shaped at an angle of 60 °. Compression ratio 14 - 15. Engine weight 1000 kg.
Heavy self-propelled artillery installation ISU-152 in the courtyard of the Chelyabinsk Kirov plant.
Spring 1944.
The total capacity of the three fuel tanks was 520 liters. Another 300 liters were transported in three external tanks, not connected to the power system. The fuel supply is forced, with the help of a twelve-plunger high-pressure fuel pump НК1.
The lubrication system is circulating, under pressure. A circulating tank is built into the tank, which ensured quick heating of the oil and the ability to use the oil dilution method with gasoline.
Cooling system - liquid, closed, with forced circulation. Radiators - two, plate-tubular, horseshoe-shaped, installed above the centrifugal fan.
To clean the air entering the engine cylinders, two VT-5 air cleaners of the "multicyclone" type were installed on the tank. The air cleaner heads were fitted with nozzles and glow plugs for heating the intake air in winter. In addition, diesel wick heaters were used to heat the coolant in the engine cooling system. The same heaters also provided heating for the fighting compartment of the vehicle in long parking lots. The engine was started by an inertial starter with manual and electric drives, or using compressed air cylinders.
The ACS transmission consisted of a dry-friction multi-plate main clutch (ferrodo steel), a four-stage eight-speed gearbox with a range multiplier, two-stage planetary swing mechanisms with a multi-plate locking clutch and two-stage final drives with a planetary row.
The chassis of the ACS, applied to one side, consisted of six twin cast road wheels with a diameter of 550 mm and three support rollers. The rear drive wheels had two removable toothed rims with 14 teeth each. Idler wheels - cast, with a crank mechanism for tensioning the tracks, interchangeable with the road wheels. Suspension - individual torsion bar. Caterpillars are steel, fine-link, each of 86 single-ridged tracks. Stamped tracks, 650 mm wide and 162 mm pitch. The gearing is pinned.
For external radio communication, a 10P or 10RK radio station was installed on the machines, for internal - an intercom TPU-4-bisF. For communication with the landing party, there was a sound signaling button at the stern.
From 1944 to 1947, 2,790 ISU-152 SPGs were manufactured. It should be noted that, as in the case of the IS-2, the Leningrad Kirovsky Plant was supposed to join the production of self-propelled guns on its basis. Until May 9, 1945, the first five ISU-152s were assembled there, and by the end of the year - another hundred. In 1946 and 1947, the production of the ISU-152 was carried out only at the LKZ.
Combat application
Since the spring of 1944, the SU-152 heavy self-propelled artillery regiments were rearmed with the ISU-152 and ISU-122 installations. They were transferred to new states and all were given the rank of guards. In total, by the end of the war, 56 such regiments were formed, each had 21 ISU-152 or ISU-122 vehicles (some of these regiments were of mixed composition). On March 1, 1945, the 143rd separate tank Nevelsk brigade in the Belarusian-Lithuanian military district was reorganized into the 66th Guards Nevelsk heavy self-propelled artillery brigade of the RVGK three-regiment composition (1804 people, 65 ISU-122, 3 SU-76).
Heavy self-propelled artillery regiments attached to tank and rifle units and formations were primarily used to support infantry and tanks in the offensive. Following in their battle formations, self-propelled guns destroyed enemy firing points and provided infantry and tanks with a successful advance. In this phase of the offensive, self-propelled guns became one of the main means of repelling tank counterattacks. In a number of cases, they had to move forward in the battle formations of their troops and take the blow, thereby ensuring the freedom of maneuver of the supported tanks.
So, for example, on January 15, 1945 in East Prussia, in the Borove region, the Germans, up to one regiment of motorized infantry with the support of tanks and self-propelled guns, counterattacked the battle formations of our advancing infantry, with which the 390th Guards Self-Propelled Artillery Regiment operated.
The infantry, under pressure from superior enemy forces, retreated behind the combat formations of the self-propelled gunners, who met the German blow with concentrated fire and covered the supported units. The counterattack was repulsed, and the infantry again got the opportunity to continue their offensive.
ISU-152 used as a fixed firing point. West Bank of the Suez Canal, Genif Hills, south of Ismaylia. 1973 year.
Heavy SPGs were sometimes involved in artillery barrage. At the same time, the fire was conducted both with direct fire and from closed positions. In particular, on January 12, 1945, during the Sandomierz-Silesian operation, the 368th ISU-152 Guards Regiment of the 1st Ukrainian Front fired for 107 minutes at the enemy stronghold and four artillery and mortar batteries. Firing 980 shells, the regiment suppressed two mortar batteries, destroyed eight guns and up to one battalion of enemy soldiers and officers. It is interesting to note that additional ammunition was laid out in advance at firing positions, but first of all, the shells that were in combat vehicles were spent, otherwise the rate of fire would have been significantly reduced. For the subsequent replenishment of heavy self-propelled guns with shells, it took up to 40 minutes, so they stopped firing well before the start of the attack.
The heavy self-propelled guns were used very effectively against enemy tanks. For example, in the Berlin operation on April 19, the 360th Guards Heavy Self-Propelled Artillery Regiment supported the offensive of the 388th Infantry Division. Parts of the division captured one of the groves east of Lichtenberg, where they were entrenched. The next day, the enemy, with a force of up to one infantry regiment, supported by 15 tanks, began to counterattack. While repelling attacks during the day, 10 German tanks and up to 300 soldiers and officers were destroyed by the fire of heavy self-propelled guns.
In the battles on the Zemland Peninsula during the East Prussian operation, the 378th Guards Heavy Self-Propelled Artillery Regiment, while repelling counterattacks, successfully used the formation of the regiment's battle formation in a fan. This provided the regiment with shelling in the 180 ° sector, which facilitated the fight against enemy tanks attacking from different directions. One of the ISU-152 batteries, having built its battle formation in a fan on a front with a length of 250 m, successfully repelled a counterattack of 30 enemy tanks on April 7, 1945, knocking out six of them. The battery did not suffer losses. Only two vehicles received minor damage to the chassis.
At the final stage of the Great Patriotic War, battles in large settlements, including well-fortified ones, became a characteristic feature of the use of self-propelled artillery. As you know, an attack on a large settlement is a very complex form of combat and by its nature differs in many respects from an offensive battle under normal conditions. Military operations in the city were almost always divided into a series of separate local battles for separate targets and centers of resistance. This forced the advancing troops to create special assault detachments and groups with great independence to conduct battle in the city. Assault detachments and assault groups were the basis of the combat formations of formations and units leading the battle for the city.
Self-propelled artillery regiments and brigades were attached to rifle divisions and corps, in the latter they were attached in whole or in parts to rifle regiments, in which they were used to reinforce assault detachments and groups. The assault groups included self-propelled artillery batteries and separate installations (usually two). The self-propelled guns that were part of the assault groups had the task of directly escorting infantry and tanks, repelling counterattacks by enemy tanks and self-propelled guns, and securing them on occupied targets. Accompanying the infantry, self-propelled guns with direct fire from a place, less often from short stops
destroyed enemy firing points and anti-tank guns, his tanks and self-propelled guns, destroyed rubble, barricades and houses adapted for defense, and thereby ensured the advance of troops. Volley fire was sometimes used to destroy buildings, with very good results. In the battle formations of assault groups, self-propelled artillery installations usually moved together with tanks under the cover of infantry, but if there were no tanks, then they moved with the infantry. The advancement of self-propelled artillery installations for actions in front of the infantry turned out to be unjustified, since they suffered heavy losses from enemy fire.
In the 8th Guards Army of the 1st Belorussian Front, in the battles for the city of Poznan, two or three ISU-152s of the 394th Guards Heavy Self-Propelled Artillery Regiment were included in the assault groups of the 74th Guards Rifle Division. On February 20, 1945, in the battles for the 8th, 9th and 10th quarters of the city, directly adjacent to the southern part of the fortress citadel, an assault group consisting of an infantry platoon, three ISU-152 and two T-34 tanks cleared the quarter from the enemy No. 10. Another group consisting of an infantry platoon, two ISU-152 self-propelled artillery mounts and three TO-34 flamethrowers stormed the 8th and 9th quarters. In these battles, the self-propelled guns acted quickly and decisively. They approached the houses and at close range destroyed the German firing points placed in the windows, basements and other places of buildings, and also made gaps in the walls of buildings for the passage of their infantry. When operating along the streets, self-propelled guns moved, clinging to the walls of houses and destroying enemy fire weapons located in buildings on the opposite side. With their fire, the installations mutually covered each other and ensured the advancement of infantry and tanks. The self-propelled artillery mounts moved forward alternately in rolls, as the infantry and tanks advanced. As a result, the quarters were quickly occupied by our infantry and the Germans retreated to the citadel with heavy losses.
The ISU-152 was in service with the Soviet Army until the 1970s, right up to the beginning of the arrival of a new generation of self-propelled guns in the troops. At the same time, the ISU-152 was modernized twice. The first time was in 1956, when the self-propelled guns received the designation ISU-152K. A commander's cupola with a TPKU device and seven viewing blocks of the TNP were installed on the roof of the cabin; the ML-20S howitzer-gun ammunition was increased to 30 rounds, which required a change in the location of the internal equipment of the fighting compartment and additional ammunition stowage; instead of the ST-10 sight, an improved PS-10 telescopic sight was installed. All machines were equipped with a DShKM anti-aircraft machine gun with 300 rounds of ammunition. The ACS was equipped with a V-54K engine with a power of 520 hp. with an ejection cooling system. The capacity of the fuel tanks was increased to 1280 liters. The lubrication system has been improved, the design of the radiators has changed. In connection with the ejection cooling system of the engine, the fastening of the external fuel tanks was also changed. The vehicles were equipped with 10-RT and TPU-47 radio stations. The mass of the self-propelled gun increased to 47, 2 tons, but the dynamic characteristics remained the same. The power reserve increased to 360 km.
The second version of the modernization was designated ISU-152M. The vehicle was equipped with modified units of the IS-2M tank, a DShKM anti-aircraft machine gun with 250 rounds of ammunition and night vision devices.
In addition to the Soviet Army, the ISU-152 was in service with the Polish Army. As part of the 13th and 25th self-propelled artillery regiments, they took part in the final battles of 1945. Soon after the war, the Czechoslovak People's Army also received the ISU-152. In the early 1960s, one regiment of the Egyptian army was also armed with the ISU-152. In 1973, they were used as fixed firing points on the banks of the Suez Canal and fired at Israeli positions.
