Soviet SAU of times of war (part 2) - Su-122
SU-122 is the average Soviet mass self-propelled gun of the class of assault guns (with minor restrictions, it could serve as a self-propelled howitzer). This machine was one of the first self-propelled guns that were taken into large-scale production in the USSR. The stimulus for the creation of self-propelled guns was the need for maximum simplification of the design tank T-34 in difficult conditions for the country in the middle of 1942 and the need to give the tank and mechanized units a highly mobile and powerful means of fire support.
The Plenum of the GAU Artillery Committee, held on April 15, in which representatives from the military, industry, and the People’s Commissariat of Arms took part, determined the development directions of the Soviet self-propelled artillery. The Red Army was to have an infantry assault-assault-assault-assault-assault infantry support system armed with a ZIS-1942 divisional gun, an X-NUMX-mm howitzer M-76 and a self-propelled do-bomber fighter, armed with an 3-mm howitzer ML-122 cannon. In general, the decisions of the plenum were reduced to the creation of such a self-propelled artillery system that could provide support and support for the advancing infantry and tanks with their fire, were able to follow the advancing forces and open fire at any moment. The decisions taken at the plenary session were approved by the State Defense Committee.
In the shortest possible time, by the 30 of November 1942, the design work was completed at the Ural Heavy Machinery Plant (UZTM, Uralmash) and the first prototype of the SU-122 was manufactured. Due to the lack of self-propelled artillery, the ACS SU-122 was launched into mass production in December, during which the machine was constantly subjected to numerous modifications related to the hasty launch of the series and an insignificant testing period. The ACS was produced from December 1942 of the year to August of the 1943 year, in total, the 638 self-propelled guns of this series were released. The release of the SU-122 was discontinued due to the transition to the production of the SU-85 tank destroyer, which was created on its base.
Design features
The SU-122 SAU had the same layout as all other serial Soviet self-propelled guns, with the exception of the SU-76. The fully armored hull was divided into 2 units. In the anterior there was an armored cabin, which housed the crew, gun and ammunition - it combined in itself a command and control unit and a combat unit. In the stern of the car were the engine and transmission. The crew of SAU consisted of 5 people. Three crew members were located to the left of the gun: the driver was the first, the gunner was behind him, the loader was behind them. Another 2 person was right from the gun - the commander of self-propelled gun and castle. The fuel tanks were located along the sides between the shafts of the individual spring suspension units, including in the manned compartment of the vehicle. Such an arrangement adversely affected the crew’s survival rate and explosion safety in case of a self-propelled self-propelled gun.
A relatively large self-propelled crew (5 man) was needed, since the 122-mm gun had separate loading, a piston gate and a guidance mechanism spread on both sides of the gun. To the right was the flywheel of the sector lifting mechanism, and to the left was the flywheel of the screw turning mechanism.
The armored hull and cabin of the ACS were made of rolled armor plates with thickness 45, 40, 20 and 15 mm. by welding, booking self-propelled guns was counterdischarged. Armor plates of the forehead of the cabin and the body of the ACS had rational angles of inclination. On the prototype and the first versions of the ACS, the frontal part of the cabin was assembled from 2-x armor plates installed at different angles of inclination, but later it was replaced with a single piece, which was installed at an angle of 50 degrees to the normal.
For ease of maintenance and repair, the overmotor armor plates were made removable, and the upper stern detail was hinged. In the roof of the armored jacket there were 2 large openings - for installation of the observation turret of the panoramic sight and the landing hatch / disembarking hatch. This hatch (with the exception of the emergency at the bottom of the hull) was the only means of the crew to leave the SAU. The driver's hatch in the frontal armor plate of the cabin was used only to observe the road. Due to howitzer armored recoil devices it could not be opened completely. All this in aggregate significantly complicated the evacuation of the crew from the wrecked car.
The main armament of the ACS was the slightly modified howitzer M-30С, created on the basis of a threaded 122-mm howitzer M-30 of model 1938 of the year. The differences between the swinging parts of the towed and self-propelled variants were insignificant and were mainly associated with the need to mount the gun in the tight space of the armored shell. From the M-30 howitzer, the gun retained the controls for the guidance mechanisms separated on both sides of the barrel, which required the presence of two gunners in the SAU crew. The M-30S howitzer had a barrel of 22,7 caliber in length, the range of direct fire was 3,6 km., The maximum firing range was 8 km. The range of elevation angles ranged from -3 to + 20 degrees. The horizontal guidance sector was limited to 20 degrees. The rotary mechanism of the gun was screw-type and was located to the left of the barrel, it was serviced by the gunner. The lifting mechanism of the gun was on the right, it had to be serviced by the SAU commander. Howitzer had a mechanical manual descent.
Ammunition howitzer consisted of 40 shots of separate-cartridge loading. Most of the ammunition was high-explosive fragmentation shots. In some cases, to fight the enemy tanks, at a distance of up to 1000 meters, cumulative projectiles were used, which, with a weight of 13,4 kg., Were able to penetrate 100 mm of armor. The mass of high-explosive fragmentation projectiles was 21,7 kg. For self-defense, the crew of the SA-122 used the 2 submachine gun PPSh (20 disks on 1420 ammunition), as well as the 20 hand grenades F-1.
The SU-122 ACS was set in motion by a four-stroke V-shaped twelve-cylinder diesel engine B-2-34, which was liquid-cooled. Maximum power in 500 HP diesel engine developed at 1800 rpm. The operating power was 400 hp, which was achieved at 1700 rpm. The engine was started either using the CT-700 starter with an 15 horsepower or with compressed air from 2 cylinders. The total capacity of the fuel tanks was 500 liters. This fuel reserve was enough for 400 km. march on the highway.
Chassis ACS almost completely repeated the base tank T-34. On each side, there were 5 large-diameter gable rollers with rubber bandage, sloth, and drive wheels. There were no supporting rollers in the undercarriage, the upper part of the track was supported by self-propelled roller support rollers. Sloths with a crawler tension mechanism were located in the front, and the drive wheels of the cogging gear in the rear. To improve the cross-country ability, the tracks could be equipped with special lugs of various designs, which were bolted to every fourth or sixth track.
Combat application
December 28 1942 of the year at the factory site UZTM passed tests of the control machine from the installation of the December party. SAU passed 50 km. run and fired 40 shots. Tests of the machine were completed successfully, and the entire installation batch of SU-122 was transferred to the Red Army. All 25 machines produced by this time were transferred to the self-propelled artillery training center. At the same time, at the end of December, the 1942 first self-propelled artillery regiments (2 SAP and 1433 SAP) began to form, which were used on the Volkhov front. Each regiment consisted of two four-gun batteries, armed with SU-1434, as well as 122 SAU SU-16, two light tanks or armored vehicles, trucks and cars, and 76 tractors.
The first battles of the formed units conducted 14-15 in February 1943 of the year as part of the private offensive operation of the 54-th army in the Smerdyn region. During the fights that lasted 4-6 days, self-propelled artillery regiments proved their effectiveness by destroying 47 bunkers, destroying 14 anti-tank guns, from 19 to 28 cars, crushing mortar batteries with 5 and destroying enemy 4 with their fire. Fully justified and the proposed tactics of using self-propelled guns. The SAU SU-122 moved at a distance in 400-600 meters behind the attacking tanks, suppressing the firing points detected by the fire, mainly firing from the stops. If necessary, self-propelled guns could be used to repel enemy counterattacks, acting as traditional howitzer artillery.
However, it was not always possible to adhere to this tactic. So already in the battle on the Kursk Bulge, vehicles were often used in the first line of the offensive, often replacing conventional tanks in attacks. As a result, vehicles unsuitable for fighting in the first line (insufficient booking, lack of machine guns, a narrow sector of shelling) suffered unnecessarily large losses. In the course of the Battle of Kursk, the Soviet command placed great hopes on the SU-122 as an effective means of fighting the Wehrmacht’s armored vehicles, but the real successes of the self-propelled guns in the fight against the tanks were very modest and the losses were significant.
SU-122 participated in the 1446 SAP and in the infamous counterattack near Prokhorovka. As a result of the misuse of 20, the 11 machines participating in the counterattack were burned, and 6 was also destroyed. At the same time, an important role in the defensive actions of units armed with self-propelled guns SU-122 was played by counterpreparation — shooting from closed positions at remote targets — clusters of enemy equipment and infantry. One way or another, the Battle of Kursk became the site of their most massive use. Already in August, the new SU-1943 vehicles, which belonged to the tank destroyer class, began to be introduced to replace 85.
Performance characteristics: SU-122
Mass: 29,6 t.
Dimensions:
Length 6,95 m., Width 3,0 m., Height 2,15 m.
Crew: 5 people.
Reservations: from 15 to 45 mm.
Armament: X-NUMX-mm howitzer M-122C
Ammunition: 40 shells
Engine: a twelve-cylinder V-shaped diesel engine B-2-34 horsepower 500.
Maximum speed: on the highway - 55 km / h, over rough terrain - 20 km / hour
Power reserve: on the highway - 400 km.
The Plenum of the GAU Artillery Committee, held on April 15, in which representatives from the military, industry, and the People’s Commissariat of Arms took part, determined the development directions of the Soviet self-propelled artillery. The Red Army was to have an infantry assault-assault-assault-assault-assault infantry support system armed with a ZIS-1942 divisional gun, an X-NUMX-mm howitzer M-76 and a self-propelled do-bomber fighter, armed with an 3-mm howitzer ML-122 cannon. In general, the decisions of the plenum were reduced to the creation of such a self-propelled artillery system that could provide support and support for the advancing infantry and tanks with their fire, were able to follow the advancing forces and open fire at any moment. The decisions taken at the plenary session were approved by the State Defense Committee.
In the shortest possible time, by the 30 of November 1942, the design work was completed at the Ural Heavy Machinery Plant (UZTM, Uralmash) and the first prototype of the SU-122 was manufactured. Due to the lack of self-propelled artillery, the ACS SU-122 was launched into mass production in December, during which the machine was constantly subjected to numerous modifications related to the hasty launch of the series and an insignificant testing period. The ACS was produced from December 1942 of the year to August of the 1943 year, in total, the 638 self-propelled guns of this series were released. The release of the SU-122 was discontinued due to the transition to the production of the SU-85 tank destroyer, which was created on its base.
Design features
The SU-122 SAU had the same layout as all other serial Soviet self-propelled guns, with the exception of the SU-76. The fully armored hull was divided into 2 units. In the anterior there was an armored cabin, which housed the crew, gun and ammunition - it combined in itself a command and control unit and a combat unit. In the stern of the car were the engine and transmission. The crew of SAU consisted of 5 people. Three crew members were located to the left of the gun: the driver was the first, the gunner was behind him, the loader was behind them. Another 2 person was right from the gun - the commander of self-propelled gun and castle. The fuel tanks were located along the sides between the shafts of the individual spring suspension units, including in the manned compartment of the vehicle. Such an arrangement adversely affected the crew’s survival rate and explosion safety in case of a self-propelled self-propelled gun.
A relatively large self-propelled crew (5 man) was needed, since the 122-mm gun had separate loading, a piston gate and a guidance mechanism spread on both sides of the gun. To the right was the flywheel of the sector lifting mechanism, and to the left was the flywheel of the screw turning mechanism.
The armored hull and cabin of the ACS were made of rolled armor plates with thickness 45, 40, 20 and 15 mm. by welding, booking self-propelled guns was counterdischarged. Armor plates of the forehead of the cabin and the body of the ACS had rational angles of inclination. On the prototype and the first versions of the ACS, the frontal part of the cabin was assembled from 2-x armor plates installed at different angles of inclination, but later it was replaced with a single piece, which was installed at an angle of 50 degrees to the normal.
For ease of maintenance and repair, the overmotor armor plates were made removable, and the upper stern detail was hinged. In the roof of the armored jacket there were 2 large openings - for installation of the observation turret of the panoramic sight and the landing hatch / disembarking hatch. This hatch (with the exception of the emergency at the bottom of the hull) was the only means of the crew to leave the SAU. The driver's hatch in the frontal armor plate of the cabin was used only to observe the road. Due to howitzer armored recoil devices it could not be opened completely. All this in aggregate significantly complicated the evacuation of the crew from the wrecked car.
The main armament of the ACS was the slightly modified howitzer M-30С, created on the basis of a threaded 122-mm howitzer M-30 of model 1938 of the year. The differences between the swinging parts of the towed and self-propelled variants were insignificant and were mainly associated with the need to mount the gun in the tight space of the armored shell. From the M-30 howitzer, the gun retained the controls for the guidance mechanisms separated on both sides of the barrel, which required the presence of two gunners in the SAU crew. The M-30S howitzer had a barrel of 22,7 caliber in length, the range of direct fire was 3,6 km., The maximum firing range was 8 km. The range of elevation angles ranged from -3 to + 20 degrees. The horizontal guidance sector was limited to 20 degrees. The rotary mechanism of the gun was screw-type and was located to the left of the barrel, it was serviced by the gunner. The lifting mechanism of the gun was on the right, it had to be serviced by the SAU commander. Howitzer had a mechanical manual descent.
Ammunition howitzer consisted of 40 shots of separate-cartridge loading. Most of the ammunition was high-explosive fragmentation shots. In some cases, to fight the enemy tanks, at a distance of up to 1000 meters, cumulative projectiles were used, which, with a weight of 13,4 kg., Were able to penetrate 100 mm of armor. The mass of high-explosive fragmentation projectiles was 21,7 kg. For self-defense, the crew of the SA-122 used the 2 submachine gun PPSh (20 disks on 1420 ammunition), as well as the 20 hand grenades F-1.
The SU-122 ACS was set in motion by a four-stroke V-shaped twelve-cylinder diesel engine B-2-34, which was liquid-cooled. Maximum power in 500 HP diesel engine developed at 1800 rpm. The operating power was 400 hp, which was achieved at 1700 rpm. The engine was started either using the CT-700 starter with an 15 horsepower or with compressed air from 2 cylinders. The total capacity of the fuel tanks was 500 liters. This fuel reserve was enough for 400 km. march on the highway.
Chassis ACS almost completely repeated the base tank T-34. On each side, there were 5 large-diameter gable rollers with rubber bandage, sloth, and drive wheels. There were no supporting rollers in the undercarriage, the upper part of the track was supported by self-propelled roller support rollers. Sloths with a crawler tension mechanism were located in the front, and the drive wheels of the cogging gear in the rear. To improve the cross-country ability, the tracks could be equipped with special lugs of various designs, which were bolted to every fourth or sixth track.
Combat application
December 28 1942 of the year at the factory site UZTM passed tests of the control machine from the installation of the December party. SAU passed 50 km. run and fired 40 shots. Tests of the machine were completed successfully, and the entire installation batch of SU-122 was transferred to the Red Army. All 25 machines produced by this time were transferred to the self-propelled artillery training center. At the same time, at the end of December, the 1942 first self-propelled artillery regiments (2 SAP and 1433 SAP) began to form, which were used on the Volkhov front. Each regiment consisted of two four-gun batteries, armed with SU-1434, as well as 122 SAU SU-16, two light tanks or armored vehicles, trucks and cars, and 76 tractors.
The first battles of the formed units conducted 14-15 in February 1943 of the year as part of the private offensive operation of the 54-th army in the Smerdyn region. During the fights that lasted 4-6 days, self-propelled artillery regiments proved their effectiveness by destroying 47 bunkers, destroying 14 anti-tank guns, from 19 to 28 cars, crushing mortar batteries with 5 and destroying enemy 4 with their fire. Fully justified and the proposed tactics of using self-propelled guns. The SAU SU-122 moved at a distance in 400-600 meters behind the attacking tanks, suppressing the firing points detected by the fire, mainly firing from the stops. If necessary, self-propelled guns could be used to repel enemy counterattacks, acting as traditional howitzer artillery.
However, it was not always possible to adhere to this tactic. So already in the battle on the Kursk Bulge, vehicles were often used in the first line of the offensive, often replacing conventional tanks in attacks. As a result, vehicles unsuitable for fighting in the first line (insufficient booking, lack of machine guns, a narrow sector of shelling) suffered unnecessarily large losses. In the course of the Battle of Kursk, the Soviet command placed great hopes on the SU-122 as an effective means of fighting the Wehrmacht’s armored vehicles, but the real successes of the self-propelled guns in the fight against the tanks were very modest and the losses were significant.
SU-122 participated in the 1446 SAP and in the infamous counterattack near Prokhorovka. As a result of the misuse of 20, the 11 machines participating in the counterattack were burned, and 6 was also destroyed. At the same time, an important role in the defensive actions of units armed with self-propelled guns SU-122 was played by counterpreparation — shooting from closed positions at remote targets — clusters of enemy equipment and infantry. One way or another, the Battle of Kursk became the site of their most massive use. Already in August, the new SU-1943 vehicles, which belonged to the tank destroyer class, began to be introduced to replace 85.
Performance characteristics: SU-122
Mass: 29,6 t.
Dimensions:
Length 6,95 m., Width 3,0 m., Height 2,15 m.
Crew: 5 people.
Reservations: from 15 to 45 mm.
Armament: X-NUMX-mm howitzer M-122C
Ammunition: 40 shells
Engine: a twelve-cylinder V-shaped diesel engine B-2-34 horsepower 500.
Maximum speed: on the highway - 55 km / h, over rough terrain - 20 km / hour
Power reserve: on the highway - 400 km.
Information