Flak - super anti-aircraft guns of the Third Reich. The most powerful anti-aircraft guns of World War II. Part 1

Higher and higher

By 1933, having designed a very successful 88-mm anti-aircraft gun “8.8-cm Flak 18” (Acht-comma-acht Zentimeter - 8.8 cm), colloquially called “acht-acht” (see NIT No. 1 and No. 2 for 2012), the Germans did not rest on this, but continued to work on even more powerful anti-aircraft guns. In addition to his love for “big guns” and Hitler’s opinion that anti-aircraft guns were precisely the means that would prevent enemy aircraft from entering the skies of Germany (anti-aircraft guns, throwing their deadly cargo into the skies, were supposed to help preserve and even increase the morale of the population), this was also explained for quite prosaic reasons. The fact is that the newly designed bombers climbed, as the song sang, “higher and higher.” And if in the early 30s the effective fire altitude of the Flak 18 anti-aircraft gun, amounting to 7.6 thousand meters, was more than enough to drive any existing enemy bomber into the ground, then since 1936 a medium bomber appeared in the British arsenal “ Wellington", with a maximum flight altitude of more than 7.1 thousand meters, which has already become difficult for the "aht-ahtam" to reach. Subsequently, this trend only intensified. During the bombing of German cities, Allied planes tried to fly as high as possible. So in May 1944, the command of the 1st Air Defense Division of Berlin reported to the leadership: “With the current raid altitude of 7-8 thousand meters, the 8.8 cm Flak 36/37 anti-aircraft guns have exhausted the limits of their reach.” Later, crushing raids by Allied aircraft, bombing cities and industrial facilities of the Reich, were carried out at altitudes of about 10 thousand meters. Accordingly, more powerful anti-aircraft guns were required, with a higher altitude for effective fire. And the Germans had them...

10.5 cm anti-aircraft gun on a Sonderanhanger 201 trailer in stowed position

Flak 38 and Flak 39

Back in 1933, when the first Flak 18 anti-aircraft guns were just starting to roll off assembly lines, the military ordered Rheinmetall Borsig to design a 105 mm anti-aircraft gun. Moreover, this weapon had to be “registered” not only on land, but also at sea - providing air defense for large ships of the nascent Kriegsmarine (Navy). By 1935, each company presented two prototypes of its 105-mm anti-aircraft guns, which passed comparative tests that same year. According to their results, the 105-mm gun () was recognized as the best. At the end of 1937, the final version of this weapon was put into service under the name 10.5-cm Flak 38 (10.5 Flugabwehrkanone 38). By the beginning of World War II, only 64 guns had been built.

10.5 cm Flak 38 in firing position, installed in position

In 1939, the 10.5-cm Flak 38 cannon was modernized, and from 1940, the Flak 39 began to enter the army, differing from the Flak 38 anti-aircraft gun in the design of the barrel, carriage and the type of electric motors of the guidance system. The 10.5 cm Flak 39 barrel was made as a composite barrel. The fact is that anti-aircraft guns, as weapons with high internal ballistics, had a high initial projectile velocity (the speed of the projectile when exiting the barrel), which for the 10.5-cm Flak 38 reached 860-880 m/sec. The high initial speed and, accordingly, the significant weight of the powder charge led to rapid “heating” (wear) of the barrel. With a worn barrel, the firing accuracy and height of effective anti-aircraft fire dropped sharply, but replacing it was very difficult and not cheap. Therefore, a design for prefabricated barrels was developed, which made it possible to replace not the entire barrel, but only its individual, most worn-out elements. The Flak 39 received such a barrel. The barrel had a free tube, consisting of three parts: chamber, middle and muzzle. The chamber and middle parts were connected at the front end of the chamber, and the joint between them was blocked by a sleeve. The middle and muzzle parts of the pipe were connected in the rifled part of the channel, and the joint between them did not overlap. The parts of the free pipe were collected in a shell or prefabricated pipe and tightened with nuts. The advantage of the composite pipe was the ability to replace only the middle part, which was most susceptible to “heating.”

10.5 cm Flak 38 in one of the museums

Both Flak 38 and 39 anti-aircraft guns had guidance, feeding and fuse installation mechanisms driven by electric motors. But if the Flak 38 had electro-hydraulic direct current guidance drives (the same as those of the 8.8-cm Flak 18 and 36), then on the Flak 39 they were replaced by the UTG 37 system on alternating current at industrial frequency, which had already been tested and tested on 8.8-cm Flak 37.

The Flak 38 four-gun battery was equipped with a special installation with a gasoline engine that drove a 220 V DC generator with a power of 24 kW. The generator supplied power to the electric motors mounted on the guns. Each gun had four electric motors: vertical guidance, horizontal guidance, rammer and automatic fuse installer. In the Flak 39 guns, the electric motors were converted to alternating current in order to be able to connect to industrial and municipal power grids.

The 10.5 cm Flak 39 had a semi-automatic wedge bolt with a self-cocking mechanism and an electric trigger, which allowed it to fire 12-15 rounds per minute. The semi-automatic was of a mechanical type and was cocked when rolling up. During the recoil of the barrel after firing, the bolt automatically opened, ejecting the spent cartridge case, and the spring of the bolt locking mechanism was cocked. If necessary, the shutter could be opened or closed manually. To load the projectile for the first time, the bolt had to be opened manually. The safety device allowed a shot to be fired only when the bolt was completely closed.

The recoil devices consisted of a spindle-type hydraulic recoil brake and a hydropneumatic knurler. The spring-type balancing mechanism was located under the barrel - spring compensators were mounted in two cylinders to facilitate vertical aiming of the gun.

To transport the 105-mm anti-aircraft gun, it was mounted on two wheel drives/trolleys of the Sonderanhanger 201 transporter (similar to the 88-mm Flak 18/36/37), which were disconnected when the gun was transferred from the traveling position to the combat position. From the ground, the guns fired from a cross-shaped carriage, which made it possible to conduct all-round fire with an elevation angle of up to 85 degrees. In addition, 10.5 cm Flak 39 were installed on railway platforms and on special pedestals for stationary positions.

The standard gun crew consisted of a squad commander and 9 servants, plus 2 more people when loading the gun manually.

Anti-aircraft gun 10.5 cm/65 SK C/33

For the 10.5 cm Flak 38/39, 3 types of projectiles were developed - high-explosive fragmentation with different types of fuses and two armor-piercing. The effective fire height of the gun was 9.3 thousand m (with an initial projectile speed of 880 m/s), and the ballistic ceiling of the projectile was 1.2 thousand m. The armor penetration of an armor-piercing projectile at a distance of 1 thousand m was 138 mm, with an initial speed of 860 m/s.

It is interesting that at the height of Soviet-German economic cooperation, when the Third Reich was in dire need of raw materials, and the Soviet Union in modern equipment and technologies, four 105-mm Flak 38 anti-aircraft guns were purchased from Germany. In Soviet documentation they were designated GOD (German special delivery). The anti-aircraft guns were delivered to the USSR and tested in the fall of 1940 at the anti-aircraft research site near Yevpatoria. The Flak 38 was tested in conjunction with the Soviet 100 mm L-6 and 73-K anti-aircraft guns. The ballistics of Soviet guns and Flak 38 were almost the same, but the accuracy of Flak 38 shells was twice as high. In addition, the German shell produced 700 lethal fragments, while the Soviet shell, with the same mass, produced only 300. The very precise work of the automatic fuse installer was noted. The survivability of the barrel is determined to be 1000 shots (with a drop in initial speed of 10%). Nevertheless, for some reason, perhaps in order to avoid accusations of “admiration of Western technology” (there was such an article in the criminal code), it was recommended to adopt not the German Flak 38, but a completely “raw” one, but “our own” 100-mm anti-aircraft gun 73-K. By the way, they never managed to bring it to mind.

In Germany, the 10.5 cm Flak 38 and 39 remained in production throughout the war. In August 1944, the Luftwaffe had: 116 Flak 38 and 39 in railway installations; 877 i on stationary installations; 1025 and on conveyors like Sd.Ah.201 (Sonderanhanger 201). In addition, the 10.5-cm/65 SK C/33 double-barreled anti-aircraft turret was developed for the Kriegsmarine, which was supposed to provide air defense for large warships. Such towers were installed on the pocket battleships “Deutschland”, “Scharnhorst”, “Bismarck”, on the heavy cruisers “Admiral Hipper”, “Prinz Eugen”, and they were also supposed to equip the first German aircraft carrier “Graf Zeppelin”. The installation weighed about 27 tons and had a rate of fire of 15-18 rounds/min. To compensate for the ship's pitching motion, there was an electromechanical stabilizer, but it did not work satisfactorily on the open sea.

Performance characteristics of Flak 38 and 39:

After the war, a number of 8.8 cm and 10.5 cm German anti-aircraft guns were also in service with the Soviet Army. One of these weapons was on display at the Museum of the Armed Forces in Moscow. According to American sources, several dozen 8.8 cm and 10.5 cm German guns also took part in the Korean War.

German small-caliber anti-aircraft guns against Soviet aviation (part 1)

During the Great Patriotic War, small-caliber anti-aircraft artillery and anti-aircraft machine gun installations were the main means of enemy air defense in the front line. It was from the fire of the MZA and ZPU that Soviet attack aircraft and short-range bombers suffered the main losses during air strikes on positions and concentrations of German troops, transport hubs and columns on the march. Moreover, in the second half of the war, after the Luftwaffe lost air superiority, the role of rapid-fire anti-aircraft guns only increased. Pilots of Soviet attack aircraft and dive bombers noted that the destructive fire of German small-caliber anti-aircraft guns remained very dense until the surrender of the German troops. In the first part of the review we will talk about German rifle-caliber anti-aircraft machine gun mounts. Although the Soviet Il-2 attack aircraft was low-vulnerable to small arms bullets, in 1941 the attack air regiments of the Red Army Air Force had a significant number of obsolete aircraft: I-15bis, I-153 fighters and P-5 and P-Z reconnaissance light bombers. On these vehicles, all the armor, at best, was represented only by the pilot's armored back, and the gas tanks were not protected or filled with neutral gas. In addition, the fire of German 7.92-mm anti-aircraft guns posed a danger not only for improvised attack aircraft, but also for front-line bombers: Su-2, Yak-2, Yak-4, SB-2, Ar-2, Pe-2 - which often operated at low altitude. In the initial period of the war, the Soviet command was forced to use fighter aircraft for assault operations against the advancing German troops. While older types of fighters with air-cooled engines I-15bis, I-16 and I-153 had good protection at the front, the more modern MiG-3, Yak-1 and LaGG-3 with liquid-cooled engines were quite vulnerable even to a single shot from a water jet. radiator In addition, it is reliably known that in 1941, the command of the Red Army sent long-range bombers DB-3, Il-4 and Er-2 to attack Wehrmacht columns during daylight hours. In order to accurately bombard enemy personnel, vehicles and military equipment, the bombers had to descend to a height of several hundred meters, falling into the effective fire zone of anti-aircraft machine guns. Thus, in the initial period of the war, ZPUs in the German army played an important role in providing protection against low-altitude bombing attacks by Soviet aircraft.

Most often, for firing from German rifles and machine guns during the Second World War, the 7.92x57 mm cartridge with an Ss bullet (German: Schweres spitzgeschoß - pointed heavy) weighing 12.8 g was used. It left the 700 mm barrel at a speed of 760 m/ With. For firing from anti-aircraft 7.92 mm machine guns, the Germans very widely used cartridges with SmK armor-piercing bullets (German: Spitzgeschoß mit Kern - pointed with a core). At a distance of 100 m, this bullet weighing 11.5 g with an initial speed of 785 m/s along the normal line could penetrate 12 mm of armor. The ammunition of anti-aircraft machine guns could also include cartridges with armor-piercing incendiary bullets PmK - (German: Phosphor mit Kern - phosphorus with a core). The armor-piercing incendiary bullet weighed 10 g and had an initial speed of 800 m/s.

German 7.92 mm armor-piercing tracer cartridge

To adjust anti-aircraft fire, a cartridge with an armor-piercing tracer bullet SmK L'spur - (German: Spitzgeschoß mit Kern Leuchtspur - pointed tracer with a core) was loaded into the machine gun belt every 3-5 regular or armor-piercing cartridges. An armor-piercing tracer bullet weighing 10 g accelerated in the barrel to 800 m/s. Its tracer burned at a range of up to 1000 m, which exceeded the range of effective fire on air targets for 7.92 mm weapons. In addition to adjustment and target designation, an armor-piercing tracer cartridge, when penetrating the wall of a gas tank, could ignite fuel vapors.

Let's start the story about German anti-aircraft machine guns of rifle caliber with the MG.08, which was a German version of the Hiram Maxim system. This weapon was actively used by the German army during the First World War, including for firing at air targets. In the first half of the 30s, as part of a program to improve machine gun armament initiated by the Reichswehr Armament Directorate, the machine gun was modernized.

As a result of the modernization, the MG.08, used for air defense purposes, received an anti-aircraft sight, an extendable anti-aircraft tripod and a shoulder rest, and the rate of fire was increased to 650 rounds/min. However, the mass of the machine gun in the firing position exceeded 60 kg, which did not contribute to its mobility. For this reason, during the Second World War, MG.08 machine guns were mainly used for anti-aircraft cover of rear units.

Modern reconstruction: a shooter with an MG.08 machine gun on a Dreifuss 16 anti-aircraft tripod

Most often, German anti-aircraft Maxims were installed on stationary positions or various transport mobile platforms: horse-drawn carts, cars and railway cars. Although this water-cooled machine gun was considered obsolete by the beginning of World War II, its reliable, albeit somewhat heavy design and the ability to conduct intense fire without the risk of barrel overheating allowed it to remain in service. MG.08 anti-aircraft machine guns were available in reserve and security units, as well as in stationary installations in fortified areas until the end of hostilities. When the crew did not need to move the weapon on themselves, the outdated water-cooled machine gun performed very well. In terms of fire density, it was not inferior to other, more modern machine guns. Moreover, the MG.08 could fire longer than the new air-cooled models without the risk of barrel overheating.

Due to its heavy weight, the mobility of the MG.08 did not meet modern requirements, and in the early 30s, several promising infantry machine guns were created in Germany that were more in line with the military’s ideas about weapons of maneuver warfare. The first model put into service in 1931 was the MG.13 light machine gun, developed using the MG.08 automatic operation scheme. Specialists from Rheinmetall-Borsig AG tried to make the weapon as light as possible. At the same time, water cooling of the barrel and belt feeding were abandoned. The barrel on the MG.13 has become removable. The machine gun used 75-round drums or a 25-round box magazine. The weight of the unloaded weapon was 13.3 kg, the rate of fire was up to 600 rounds/min. To reduce dimensions, the tubular stock with a folding shoulder rest was folded to the right. Along with the sector sight on the MG.13, it was possible to install an anti-aircraft ring sight.

The crew of the MG.13 machine gun prepared to fire at an air target

Despite the advantage of the MG.13 over the outdated standard Reichswehr light machine gun MG.08/15, it had many disadvantages: design complexity, long barrel changes and high cost of production. In addition, the military was not satisfied with the magazine feed system, which increased the weight of the ammunition carried and reduced the combat rate of fire, which made the machine gun ineffective during intensive firing from the machine.

MG.13 machine gun with a 75-round drum magazine on an anti-aircraft tripod

Therefore, relatively few MG.13s were produced; mass production continued until the end of 1934. However, the Wehrmacht had MG.13 machine guns during the initial period of the war. For anti-aircraft shooting, the MG.13 could be mounted on the MG.34 machine gun.

In 1934, the MG.34 machine gun, which is often called the “first single”, entered service. It quickly gained popularity in the Wehrmacht and greatly displaced other models. The MG.34, created by Rheinmetall-Borsig AG, embodied the concept of a universal machine gun, developed based on the experience of the First World War, which could be used as a manual machine gun when firing from a bipod, as well as a mounted machine gun from an infantry or anti-aircraft machine gun. From the very beginning it was envisaged that the MG.34 machine gun would also be installed on armored vehicles and tanks, both in ball mounts and on various turrets. Such unification simplified the supply and training of troops and ensured high tactical flexibility.

The MG.34 mounted on the machine was fed by belts from a box of 150 rounds or 300 rounds. In the manual version, compact cylindrical boxes with 50 cartridges were used. In 1938, a magazine-fed modification was adopted for anti-aircraft guns: for machine guns, the cover of the box with the tape drive mechanism was replaced with a cover with a mount for a 75-round twin drum magazine, structurally similar to the magazines of the MG.13 light machine gun and the MG.15 aircraft. The store consisted of two connected drums, cartridges from which were fed alternately. The advantage of a magazine with alternate supply of cartridges from each drum, in addition to a relatively large capacity, was considered to be the preservation of the balance of the machine gun as the cartridges were consumed. Although the rate of fire when fed from a drum magazine was higher, this option did not take root in anti-aircraft guns. Most often, belt-fed machine guns from a cylindrical 50-round box were used to fire at aircraft. Drum magazines were not popular due to their high sensitivity to contamination and the complexity of the equipment.

Anti-aircraft crew of the Norwegian SS Legion at a firing position, the MG.34 mounted on a tripod is powered from a 50-cartridge box

MG.34 had a length of 1219 mm and in the manual version without cartridges weighed just over 12 kg. The first series of machine guns had a rate of fire of 800-900 rounds/min. However, based on combat experience, due to the use of a lighter bolt, the rate was increased to 1200 rounds/min. In case of overheating, the barrel could be quickly replaced. The barrel was supposed to be changed every 250 shots. For this purpose, the kit included two spare barrels and an asbestos glove.

To fire at air targets, the MG.34 was mounted on a Dreiben 34 tripod and equipped with anti-aircraft sights. The standard machine also allowed for anti-aircraft fire using a special Lafettenaufsatzstück anti-aircraft rack, although with less convenience.

The advantages of a single ZPU using the MG.34 were: simplicity of design, relatively low weight and the ability to mount a conventional light machine gun taken from a line unit. These qualities were especially valued at the front line, since it was difficult to place more bulky anti-aircraft guns in the trenches.

Soon after the start of serial production of the MG.34, the German command was puzzled by the need for anti-aircraft cover for troops on the march. For this purpose, a horse-drawn gig MG-Wagen 34 was initially used with a kingpin installation and a box for cartridge boxes installed on it. The crew of the “anti-aircraft self-propelled gun” consisted of a driver (also the second number of the machine gun crew) and a gunner. However, this option was not particularly widespread, since the crew was in cramped conditions, and fire on the move was impossible.

ZPU Zwillingssockel 36

In 1936, the troops began to receive the MG-Wagen 36 “cart” with twin Zwillingssockel 36 installations. This ZPU provided all-round fire at air targets, with elevation angles from -14 to +73°. According to reference data, the machine gun could fire at air targets at a distance of up to 1800 m. In fact, the effective firing range at air targets did not exceed 800 m, the ceiling - 500 m. The machine with a shooter's seat and frame was mounted on a pedestal support, two machine guns were mounted on the frame, cartridge boxes with belts for 150 rounds and control handles. The machine guns had a single trigger; a ring anti-aircraft sight was located on the bracket. The combat rate of fire in short bursts was 240-300 rounds/min, and in long bursts – up to 800 rounds/min.

The MG-Wagen 36 carriage itself was a single-axle trailed vehicle, specially designed for a mobile ZPU. Its main components - an axle with two wheels, a body and a drawbar - were manufactured using “automotive” technologies. The open, riveted steel body resembles the flatbed of a small pickup truck. The axle had no suspension, but was rigidly attached to the body. The wheels are car wheels, from a light truck. The hubs are equipped with mechanically driven drum brakes.

When parked, the stability of the cart on two wheels is ensured by two folding racks located in front and behind the body. A drawbar with a towing device made it possible to hook the cart to the gun limber, which was harnessed to a pair of horses.

An important advantage of the MG-Wagen 36 was its constant readiness for combat while driving. However, it soon became clear that horses in most cases are very frightened by aircraft flying at low altitude, and shelling and bombing from the air generally make them uncontrollable, which of course greatly reduced the effectiveness of a horse-drawn anti-aircraft machine gun mount. In this regard, a towed cart with a twin machine gun was often hitched to various vehicles with an internal combustion engine, for example, to the Sd.Kfz.2 half-track motorcycle. Towed MG-Wagen 36 vehicles were seen on the Eastern Front until mid-1942. A number of Zwillingssockel 36 ZPUs were installed on trucks, railway platforms and armored vehicles.

In addition to single and twin anti-aircraft machine gun installations, the Germans built a small number of quadruple anti-aircraft machine guns. In the case of using the MG.34 later versions, the total rate of fire in this case was 4800 rounds/min - twice as much as that of the Soviet quad 7.62-mm anti-aircraft machine gun M4 mod. 1931, which used four Maxim machine guns mod. 1910/30 Since the MG.34 machine guns were air-cooled, the weight of the German installation was approximately 2.5 times less.

A Red Army soldier at a 16-barrel captured machine gun mount, created using MG.34 machine guns

However, in Germany during the war years, attempts were made to create real 16-barreled monsters, which, given the total shortage of machine gun weapons in the second half of the war, was an unacceptable waste for Germany.

For all its advantages, the MG.34 was complex and expensive to produce. In addition, during the fighting on the Eastern Front, it turned out that the machine gun is very sensitive to wear of parts and the state of lubrication, and its proper maintenance requires highly qualified machine gunners. Even before the launch of the MG.34 into mass production, the Infantry Weapons Department of the Ground Forces Armament Directorate drew attention to its high cost and complex design. In 1938, the company Metall-und Lackwarenfabrik Johannes Großfuß presented its version of the machine gun, which, like the MG.34, had a short barrel stroke with the bolt locked by rollers and moved to the sides. But unlike the MG.34, the new machine gun made extensive use of stamping and spot welding. As in the MG.34 machine gun, the problem of barrel overheating during prolonged shooting was solved by replacing it. Development of the new machine gun continued until 1941. After comparative tests with the improved MG.34/41, it was put into service in 1942 under the designation MG.42. Compared to the MG.34, the cost of the MG.42 has decreased by about 30%. The production of MG.34 took approximately 49 kg of metal and 150 man-hours, for MG.42 - 27.5 kg and 75 man-hours. MG.42 machine guns were produced until the end of April 1945, the total production at the enterprises of the Third Reich amounted to more than 420,000 units. At the same time, the MG.34, despite its shortcomings, was produced in parallel, albeit in smaller quantities.

An American soldier with a captured MG.42 twin anti-aircraft gun

The MG.42 machine gun had the same length as the MG.34 - 1200 mm, but was slightly lighter - 11.57 kg without cartridges. Depending on the mass of the bolt, its rate of fire was 1000-1500 rounds/min. Due to its higher rate of fire, the MG.42 was even more suitable for anti-aircraft fire than the MG.34. However, by the start of mass production of the MG.42, it became clear that the role of rifle-caliber anti-aircraft launchers in the air defense system, due to the increase in security and flight speed of combat aircraft, had sharply decreased. For this reason, the number of specialized anti-aircraft installations in which the MG.42 was used was relatively small. At the same time, MG.42 machine guns were widely used in universal turrets on armored personnel carriers and tanks.

MG.34 and especially MG.42 are rightfully considered one of the best machine guns used during the Second World War. In the post-war period, these weapons spread widely around the world and were actively used in regional conflicts. Modifications of the MG.42 chambered for other cartridges and with bolts of various weights were mass-produced in different countries and, in addition to infantry variants on bipods and machine guns, they can often still be found installed on anti-aircraft turrets as part of the armament of various armored vehicles.

At the end of the part devoted to rifle-caliber anti-aircraft machine gun mounts developed and produced in Germany, we will try to evaluate how effective they were. As already mentioned, to carry out bombing attacks on the positions and transport columns of the Nazis, the Soviet Air Force used both armored attack aircraft and fighters and light bombers not protected by armor protection.

On the Il-2 attack aircraft, the engine, cockpit and fuel tanks were covered with a streamlined armored body and armored partitions with a thickness of 4 to 12 mm. The steel armor included in the aircraft's power kit was supplemented with laminated armored glass. The canopy was made of 64 mm glass. The windshield withstood fire from 7.92 mm armor-piercing bullets fired at point-blank range. The armor protection of the cabin and engine, due to the significant angles of contact with the armor, in most cases was not penetrated by armor-piercing rifle-caliber bullets. Often attack aircraft returned from a combat mission with dozens and sometimes hundreds of holes from bullets and fragments of anti-aircraft shells. According to Russian historian O.V. Rastrenin, during combat operations, 52% of IL-2 hits were on the wing and the unarmored part behind the cockpit, 20% of the damage was on the fuselage as a whole. The engine and hoods received 4% damage, the radiators, cab and rear gas tank each received 3% damage.

However, these statistics have a significant flaw. It can be said with complete confidence that there were more IL-2s shot down due to hits in critical parts: the engine, cockpit, gas tanks and radiators. Experts who examined aircraft that had received combat damage in most cases did not have the opportunity to inspect attack aircraft hit by anti-aircraft fire in the target area. It is known that during the Great Patriotic War, about half of the patients in Soviet hospitals had wounds in the limbs. But this does not mean that bullets do not hit the head and chest. This is evidence that those who received bullet wounds to the head and chest, in most cases, die on the spot. Therefore, drawing conclusions only on the basis of damage to returning aircraft is a mistake. The planes and fuselage riddled with bullets and shrapnel do not require additional protective measures. Their strength was enough to continue flight even with extensive damage to the skin and power kit.

But in any case, it can be argued that the IL-2 was sufficiently protected from light small arms fire. As a rule, 7.92-mm bullets did not penetrate armor, and their destructive effect on the power elements of the attack aircraft’s structure in single hits was insignificant. But at the same time, it would be wrong to say that rifle-caliber ZPUs were absolutely powerless against armored attack aircraft. A dense burst of rapid-fire machine gun could easily cause damage that would impede the completion of a combat mission. In addition, on two-seater vehicles, the gunner’s cabin was not covered with armor at all from below and from the sides. Many authors writing about the combat use of the Il-2 overlook the fact that in the depths of enemy defenses, Soviet attack aircraft had to fly at low altitudes, bypassing areas with a high concentration of anti-aircraft artillery, avoiding encounters with enemy fighters. At the same time, a long flight with the armored oil cooler shutters closed was impossible. According to the recollections of test pilot and cosmonaut Georgy Timofeevich Beregovoy, who flew on the Il-2 during the war and received the first hero star in 1944, he made an emergency landing in the forest after he received a machine-gun burst into the oil cooler while moving away from the target. In addition, pilots, especially young ones, often forgot to close the oil cooler dampers above the target.

As for fighters and unarmored short-range bombers, their survivability when fired from 7.92 mm machine guns was highly dependent on the type of power plant used. Air-cooled engines were much less vulnerable to combat damage than engines with liquid radiators. In addition to better combat survivability, the radial engine is much shorter and presents a smaller target. The majority of combat aircraft that entered service on the eve of the war had a system for filling tanks with neutral gas, which prevented an explosion of fuel vapor when hit by an incendiary bullet. In the second half of the war, fighter fuel tanks were usually protected from fuel leaks when shot through. Since the floor and side walls of the cockpit of Soviet fighters and front-line bombers were not armored, 7.92 mm bullets posed a serious danger to pilots. But much depended on the tactics used by Soviet pilots when attacking ground targets. As is known, most of the planes were shot down during repeated approaches to the target, when the German anti-aircraft crews had time to react and take aim. Rifle-caliber anti-aircraft launchers turned out to be relatively ineffective against Pe-2 and Tu-2 bombers performing dive-bombing. The introduction of the aircraft into a dive began from a height inaccessible to fire from 7.92 mm anti-aircraft guns, and on the combat course until the moment of bombing, due to the high speed and stress experienced by the shooters, it turned out to be very difficult to hit the dive bomber. And after the bombs were separated, the anti-aircraft gunners often had no time to conduct aimed fire at the aircraft.

Due to the availability of rifle-caliber machine guns and ammunition for them, these weapons were used to fire at air targets until the last hours of the war. Single and twin 7.92-mm anti-aircraft guns had smaller weight and dimensions compared to larger anti-aircraft guns. The downside of using relatively low-power and cheap 7.92 mm cartridges was the short effective firing range at air targets and the low destructive effect. So, in order to shoot down a Yak-7b fighter, on average it had to be hit by 2-3 20-mm shells or 12-15 7.92-mm bullets.

To be continued…

Author: Linnik Sergey

Flak 40

Having developed a 105-mm anti-aircraft gun, the “gloomy German genius” did not stop there. The apotheosis of his efforts and the most powerful anti-aircraft gun used during World War II was the 128 mm anti-aircraft gun. Although it was not produced in mass quantities, it undoubtedly became the most effective heavy anti-aircraft gun of its time.

128-mm Flak 40 anti-aircraft gun in combat position

The idea of ​​acquiring 128-mm anti-aircraft guns first arose among the military in 1936, and it was ordered to prepare a corresponding project, which received the internal index “Gerat 40”. Since the priority of this development was not very high, the work proceeded slowly and the final version of the prototype was ready only by 1940. Nevertheless, back in December 1938, the company was given a preliminary order for 100 anti-aircraft guns.

It was initially assumed that the Gerat 40 would be adopted by field army units, so a certain mobility was required from this installation. However, there were problems with this. The installation was so heavy - its weight in the combat position was 12 tons - that transporting it as before (on a two-axle wheeled transporter of the Sonderanhanger 201 type without disassembling) was possible only over very short distances. Therefore, it was proposed to remove the barrel and transport it on a separate trailer. But trial operation of the prototype showed that such disassembly was impractical - the installation still remained too cumbersome. As a result, a four-axle Sonderanhanger 220 transporter was developed to transport unassembled guns.

However, when the military fully realized the size and weight of the prototype presented to them, it was decided that this weapon would only be built in a stationary version. Those. the gun was installed in position on a concrete base and was not equipped with its own conveyor. The anti-aircraft gun was named 12.8-st Flak 40, and its production was given the green light. However, by that time the assembly line had already been prepared for the production of a mobile version of the 12.8-speed Flak 40, so the first six units were still built in a mobile version. They formed the only mobile battery that entered the army at the end of 1941.

Due to its large weight (12 tons), it was initially planned to transport the 12.8-cm Flak 40 in a disassembled state - the barrel was removed and transported on a separate trailer

The restructuring of production took time, and as a result, production of the stationary version of the Flak 40 began only in 1942. Taking into account the fact that the installation was very complex and expensive, by August 1944 there were only 449 Flak 40s in German service, of which 242 were stationary installations, 201 railway installations (on railway platforms) and 6 mobile installations. The placement of a relatively large number of Flak 40 guns on railway platforms is explained by the desire to ensure the mobility of air defense forces and the ability to transfer heavy anti-aircraft batteries to protect various objects. The number of Flak 40s reached its maximum in January 1945, when there were 570 units in service. They were used exclusively to protect the most important industrial facilities on the territory of the Third Reich, as well as such major cities as Berlin, Vienna, Hamburg; here, for their best use, even special anti-aircraft towers (Flaktuerme) were built.

The 12.8-st Flak 40 anti-aircraft gun had mechanisms for guidance, supply and delivery of ammunition, as well as fuse installations driven by electric motors powered by 115 V alternating current. Therefore, the four-gun battery had to be served by one 60 kW generator. The design of the carriage and the guidance mechanisms made it possible to give the barrel a maximum elevation angle of 87 degrees, and all-round firing was ensured in the horizontal plane.

Trial operation of the 12-cm Flak 40 prototype showed that disassembling the gun during transportation was impractical - the installation was still too cumbersome. As a result, a four-axle Sonderanhanger 220 transporter was developed to transport unassembled guns. 12.8-cm Flak 40 in the factory yard

The fire control of the 12.8-st Flak 40 battery was carried out using the Kommando-Gerät 40 - a fire control device with a four-meter optical rangefinder. Using the rangefinder, the following were determined: the range to the target, flight altitude and angular coordinates - azimuth and elevation - of the target. Based on them, firing data was generated, which was transmitted via cable to the guns.

Firing from the 12.8-st Flak 40 was carried out in unitary shots with fragmentation shells weighing 26 kg, which had an initial speed of 880 m/sec. The powder charge of a 128 mm shot was four times greater than that of an 88 mm shot. Technically, the gun provided a height reach of 14.8 thousand m, but the remote fuse allowed firing only up to 12.8 thousand m. To increase the effective firing ceiling of 105 mm and 128 mm anti-aircraft guns, fragmentation active rocket projectiles were developed. The muzzle velocity of such a 105-mm projectile was 800 m/s, and then the jet engine accelerated it to 1150 m/s. However, the end of the war did not allow the launch of active-missile projectiles into mass production. Similar active-missile projectiles were created for the 128-mm Flak 40 anti-aircraft gun. But here, too, everything was limited to the release of a pilot batch. Speaking about technical innovations in the design of anti-aircraft shells, we should also mention attempts to create high-frequency radio fuses for them, the action of which is based on the Doppler effect. For example, radio fuses were studied in Vienna (Kakadu fuse) and Blauppunkt-Veerke in Berlin (Trichter fuse). The value of such fuses was that they ensured non-contact detonation of the projectile when the distance between it and the target was minimal.

In addition to anti-aircraft shells, the Flak 40 could also fire armor-piercing shells of the 1940 and 1943 models, which penetrated armor 127 and 157 mm thick, respectively, at a distance of 1.5 thousand m. However, these shells were mainly used in the Jagdtiger tank destroyers.

Flak 40 mounted on one of the Berlin anti-aircraft towers

Yuri Pasholok. Dreams of Soviet self-propelled guns in the summer of 1941

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Little-known and unrealized projects of tanks and other armored vehicles

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Yuri Pasholok. Dreams of Soviet self-propelled guns in the summer of 1941

The program to create a family of self-propelled artillery units, launched in the Soviet Union shortly before the start of the Great Patriotic War

Self-propelled artillery appeared almost earlier than tanks. If we count heavy cannon armored vehicles, as well as armored trucks armed with anti-aircraft and field guns, as such, the very first self-propelled guns appeared in service with the Russian Imperial Army back in 1915. The reasons why self-propelled artillery appeared are prosaic. In the conditions of the First World War, there was a need to increase the mobility of guns, especially heavy artillery. Anti-aircraft self-propelled artillery mounts have become one of the most popular self-propelled guns. The next stage was to become heavy “self-propelled carriages”, which had significantly higher mobility than towed versions of the same systems. It so happened that the first samples of heavy self-propelled guns appeared at the very end of the First World War, so they did not make it to the front. Then funding for such projects abruptly stopped. Again, interest in self-propelled artillery units is believed to have returned by the beginning of World War II, with the Germans being the first to use them. But this is slightly wrong.

SU-5, the first more or less serial Soviet self-propelled guns that also fought

For starters, the same Germans have been working on self-propelled artillery since the second half of the 20s. Another question is that every time I ended up with a bucket of nuts. In the 20s, the British created the Birch Gun, the most successful self-propelled gun of the 20s. The fact that it did not go into a large series is already a question for the British military conservatives. Finally, the Soviet Union has also been developing self-propelled artillery since the 1920s. The peak of development of these combat vehicles, of all classes, including even tank destroyers, occurred in the mid-30s. Some of the vehicles were even put into service, but for a number of reasons large series never took place. However, the first use of Soviet self-propelled guns happened back in 1928 during the battles near Lake Khasan. Then the work died down, or so it is believed.

SU-14-BR-2, a “splinter” of the self-propelled gun program of the 30s, which was needed at the beginning of 1940

From publications devoted to domestic tank building, we can conclude that the real development of Soviet self-propelled guns began in the spring of 1942. In fact, this is not true at all. In fact, those combat vehicles, the development of which was approved in April 1942, were the development of a theme that was already almost a year old. And for others almost 2 years. Indeed, until the start of the war, work on domestic self-propelled guns proceeded rather in the background, but only because the GAU KA, at that time the “owner” of self-propelled artillery units, did not consider their creation important. The work had low priority, and there was no command from above. As a matter of fact, if in the fall of 1942 a brick had not flown towards the GAU KA from the chairman of the State Defense Committee, the artillerymen would have continued to polish the flashlights. At the same time, it is interesting in itself what kind of self-propelled artillery the Red Army command saw as of May-June 1941. We’ll talk about this today, especially since a number of topics were continued.

T-100Y, an attempt to “employ” the T-100 chassis as a “dillbox fighter”

The reasons why work on Soviet self-propelled guns of the pre-war period died down are extremely simple. Firstly, the production of self-propelled artillery units was transferred to the same factories as tanks. They were already sewn up, and now there’s an additional order. The SU-5, the most successful vehicle in terms of production, “died” precisely for this reason. Plant No. 174 was never able to produce it; as a result, a pilot batch was made by Plant No. 185. Secondly, the artillery part of the vehicle often became a problem. Comrade Syachintov particularly “distinguished himself” in this field, taking over tank and partly self-propelled artillery, and eventually destroying it. The epic with PS-3 alone is worth it. The author of the material believes that the execution was too drastic a measure, especially since “innocent victims” were usually given political articles. But what to do with the more than 30 thousand rubles in bonuses that Syachintov received for allegedly accepted self-propelled guns and artillery systems, most of which did not go into production, is the question. Moreover, AT-1 “died” solely through the fault of Syachintov. The self-propelled guns were developed for PS-3; no other system could fit into it. Thirdly, there was no base for the self-propelled guns. The T-26 turned out to be not the best base due to its layout features, and the rest of the vehicles were in trouble. No base - no self-propelled guns. Therefore, it should not be surprising that work on a new generation of self-propelled guns began only in mid-1940.

The fastest solution to the issue of assault self-propelled guns is the KV-2. Prototype on the KV U-0 chassis

The first topic to revive was the heavy self-propelled gun. At the same time, we were not talking about a self-propelled carriage at all, as in the case of the SU-14. A bunker fighter was urgently needed, and the task was issued in several directions. As a result, 2 experimental heavy self-propelled guns were born with bases that had no prospects (SU-14-BR-2 and T-100Y), as well as what was officially considered a tank. In fact, the KV-2, a child of the Soviet-Finnish war, only accidentally turned out to be a tank. Initially, it was planned to make a self-propelled gun with a non-rotating wheelhouse and a 152-mm howitzer model 1909/30 as weapons. That is, it was the self-propelled guns that were planned. But then a project with a rotating turret and a 152-mm M-10 howitzer was put into operation. People like to talk about the KV-2 about the power of its projectile and the almost exploding Tigers, but I advise the authors of such statements to play less computer games. In March 1940, the main target of the “KV with a large tower” was the Finnish battlefields. At the same time, the KV-2 was not suitable for the role of full-fledged “bunker fighters”, since the power of the gun was clearly not enough. GAU KA required breaking through 2 meters of reinforced concrete, which only the 152-mm BR-2 gun was capable of. Such a weapon did not fit into the KV-2. GABTU KA also didn’t really need this tank, because it wasn’t really a tank. To combat heavy tanks, something more powerful was required, so in the summer of 1940, the idea of ​​installing a 107-mm M-60 gun was first raised. But such a configuration could only be made in the summer of 1941, and even then as a test bench for the ZIS-6 gun for the KV-3. Since July 1941, production of the KV-2, in any case, ceased.

Officially, the KV-2 was a tank, which is why its use turned out to be incorrect

One way or another, the KV-2 can be considered the first mass-produced heavy assault self-propelled gun. Naturally, there will be a crowd of those who will consider this to be incorrect, but if we carefully read why the KV-2 was needed, we will suddenly discover an assault self-propelled gun. The fact that instead of a self-propelled gun with a fixed wheelhouse, a tank with a very large turret was formed - well, that’s how it happened. This largely explains why the KV-2 performed poorly in the summer of 1941. Created as a means of combating enemy field fortifications, the KV-2, naturally, performed poorly as a conventional tank, which it was not. True, for some reason no one was told that this was a heavy attack aircraft. Therefore, these “tanks”, overloaded at the prototype stage, rolled along with everyone else, the results of such use are quite expected. To be fair, at about the same time, on the other side of the front, two Pz.Sfl.IVa assault self-propelled guns were rolling around, created for approximately the same purpose (fighting enemy fortifications), but converted into tank destroyers. They were not very suitable for this role, because they were initially created slowly.

Self-propelled gun "212", due to problems with the base tank and changes in priorities, not even a prototype was built

For the GAU KA, however, the priority task was to create a completely different machine - a full-fledged bunker fighter. This was the heavy self-propelled gun “212”, which was created on a chassis using the same units as the experimental T-220 tank. As a matter of fact, these same units became the main problem of the car. Its body was even manufactured, but it was never brought to the state of an experimental machine. From the very beginning of testing, the T-220 showed low reliability, first in terms of the engine, and then increasingly in terms of the chassis and transmission elements. Even if we ignore what happened around the KV-3 program, and then the KV-4 and KV-5, the situation for “212” was extremely unfavorable. Subsequently, SKB-4 of the Kirov Plant created 2 more self-propelled gun projects - with guns of 130 mm and 107 mm caliber. In both cases it was a heavy tank destroyer. Initially, an analogue of the SU-B-13, by the way, was being developed back in 1940, but then it was an alternative to the “212”. Meanwhile, in conditions when there is trouble with the base chassis, you can draw anything, the result is obvious. Another important point was that “212”, like the SU-B-13, was not even close in terms of production volumes of the same KV-2. The order volume for the SU-B-13 was 10 vehicles in 1941. Before that, at the beginning of 1941, the production of 12 self-propelled guns “212” with BR-2 guns and the same number with B-13 guns was expected. One should not be surprised at such meager production volumes. The Red Army did not require hundreds of assault self-propelled guns with specific tasks.

Requirements for the A-46 tank destroyer

By the summer of 1940, when work on the 212 self-propelled guns intensified, another topic emerged. This time we were talking about a tank destroyer with all-round fire. The basis for it was the T-34 medium tank, which was just beginning to be produced. Before that, medium-sized self-propelled guns had hardly been developed, however, the very idea of ​​self-propelled guns with an anti-aircraft gun that had all-round fire already existed. We are talking about the SU-8, which was created in two versions. However, now the task was different. According to the experimental work report dated June 21, 1940, an 85-mm self-propelled gun on the chassis of the T-34 tank (tank destroyer) was supposed to be used. This self-propelled gun was supposed to have a combat weight of 26 tons and reach a maximum speed of 40 km/h. The weapon was supposed to be an 85-mm anti-aircraft gun 52-K model 1939. The contractor was Plant No. 8, developer of 52-K. For these purposes, 2 T-34 chassis were allocated, but due to the death of M.N. Loginov, chief designer of plant No. 8, as well as additional tasks, the project very quickly went into oblivion. There are no graphics left on this topic, but the direct descendant, the U-20-II tank destroyer, gives an idea of ​​the vehicle. It was also created at plant No. 8, but in Sverdlovsk.

A-46, reconstruction of the appearance by Alexander Kalashnik, Omsk. It’s not a fact that this car would have been built at all, especially considering the problems of the AT-42

A new wave of activity in the development of medium self-propelled guns began in May 1941. It is possible that this turned out to be connected with the report of Soviet foreign intelligence about the presence of heavy tanks by the Germans. By the end of May 1941, new tactical and technical requirements for a medium tank destroyer were formed. But he had little to do with the original project. Now the base was the AT-42 (A-42) tractor, which was created on the basis of the T-34. The gun, equipped with a developed gun shield, was located in the rear part, which ensured a circular firing sector. The result was something more similar to the German half-track bunker fighter 8.8 cm Flak 18 (Sfl.) auf Zugkraftwagen 12t (Sd.Kfz.8), which was actually used to fight tanks. The vehicle is bulky, but has proven to be a very successful anti-tank weapon. In the case of the Soviet analogue, it was not about copying ideas; a similar concept was born due to the similarity of the task.

These were the plans for the ZSU

According to the plans for experimental work of the GAU KA, the self-propelled artillery unit, called the A-46, was supposed to be built in September 1941. In October of the same year, tests were carried out, based on the results of which the issue of launching the series was already decided. Meanwhile, the A-46 had the same problem as the 212. It was called “AT-42 chassis”. Prototypes of the AT-42 were built, but the testing somehow didn’t work out, and plant No. 183 was pushing hard to build a fighter using the Voroshilovets tractor. Initially, this idea was abandoned, but later “Voroshilovets” repeatedly surfaced in experimental work. In addition, several variants of the self-propelled guns, called T-34 (SU), were proposed, both on the chassis of the serial T-34 and on the T-34M chassis. The version on the T-34 chassis was supposed to have a horizontal firing sector of 15 degrees, and the version on the T-34M chassis was supposed to have all-round firing. In the current situation, if the war had not started, the story with the medium tank destroyer would still have reached the stage of something realistic no earlier than the end of 1941. For some reason, I immediately remember the parable about the donkey and the padishah.

Savin anti-aircraft tank, which was created rather in spite of

There was a special atmosphere in the light self-propelled guns. Moreover, it’s worth talking first not about light assault self-propelled guns and tank destroyers, but about self-propelled guns. The topic of anti-aircraft self-propelled artillery units was pulled out of mothballs back in 1940. This happened thanks to the activity of V.I. Savin, better known for aviation weapons. Back in 1940, he proposed an anti-aircraft turret, which was later transformed into a turret for the new T-50 escort tank. But the plan for 1941 initially included something completely different - “the installation of two twin 23-mm anti-aircraft guns for the T-50 tank.” We were talking about 23-mm MP-6 aircraft cannons. Since work was going on on the tank itself, there was no time until a certain point, and in May 1941, after the arrest of Taubin and Baburin, the topic of MP-6 disappeared. Further, at the end of May 1941, requirements appeared for a ZSU with a base in the form of the T-50 and weapons in the form of a 37-mm 61-K anti-aircraft gun. The developer was again plant No. 174. The car was even given an index - SU-52, but even the preliminary design was not really completed. But Savin, who was studiously ignored, brought his project to a fairly high degree of readiness. Then the evacuation got in the way. At the same time, at the end of May 1941, the issue of installing automatic guns on the T-40 and GAZ-62 chassis was being worked out. But in the first case, instead of a ZSU, we got a series of SHIT tank destroyers, and in the second there was simply no vehicle. One could say that nothing worked out, but that is not so. The design bureau of plant No. 174 urgently developed the T-26-8, with the installation of the same 61-K. They produced 2 vehicles, they ended up in the 124th Tank Brigade. However, these are improvisations from the first months of the war, and not pre-war plans.

The SU-51 claimed the role of a light tank destroyer, actually a tank destroyer with a 57-mm ZIS-4 cannon

An equally interesting situation was happening with light tank destroyers. At the end of May 1941, tactical and technical requirements appeared for a tank destroyer using the T-50 chassis. According to the requirements, it was planned to obtain an SPG with a circular rotation turret, and it would retain the turret rotation motor. The armament consisted of a 57-mm ZIS-4 cannon. The crew and combat weight remained within the limits of the base tank, and the thickness of the hull sides was reduced to 30 mm. By and large, the result was a tank destroyer, not much different from the T-50. In June 1941, the design bureau of plant No. 174 gave this topic the index SU-51, but the outbreak of the war did not make it possible to bring the matter even to a preliminary design. In any case, before October 15, 1941, the SU-51 could not have been expected.

Thoughts on tank destroyers in early June 1941

From time to time you can hear puzzled remarks on the topic “why weren’t the chassis of old tanks used?” You shouldn’t think that GABTU KA didn’t think about this. The topic was fully explored and discussed. At the beginning of June 1941, a meeting was held during which the issue of using the T-26, BT-5 and extended STZ-5 chassis was raised. And if the decision regarding STZ-5 somehow sounded vague, then the T-26 and BT were rejected. But the idea was voiced about a “self-propelled gun carriage” using T-40 units. These good wishes remained in an uncertain status, but with the T-26, not everything is so simple. In the summer of 1941, the design bureau of plant No. 174 developed a preliminary design for the T-26-7, which, apparently, was similar to the SU-26, only with a ZIS-2 instead of a regimental gun. For a number of reasons they did not implement it, but nevertheless. But the ZIS-30 went into production.

Judging by the requirements, the future SU-26 initially looked a little different

Finally, at the end of May 1941, the idea of ​​“employment” of the double-turreted T-26 was voiced. It was assumed that the design bureau of plant No. 174 would develop a prototype of the vehicle, and then the DRO Plant in Vyksa would rework them. This development received the designation T-26-6, but initially it was not what is known as the SU-26. The protection of the crew crew from the front, from the flanks and from above was stipulated. That is, it was more about a gun shield, but the firing sector was only 15 degrees to the left and right. Alas, the original T-26-6 project has not yet been found, but what was created already during the war was clearly different from the original concept. And the SU-26 is only partly the development of the design bureau of plant No. 174, since the gun part was precisely created by SKB-4 of the Kirov Plant. It is also worth noting that the requirements also included a 76-mm self-propelled artillery mount based on the T-50, but this work was not even allowed into the design.

ZIS-30, an “unscheduled” self-propelled gun that appeared after the start of the war

In theory, there were “massive plans”, and in practice, even the T-26-6, the simplest option for obtaining self-propelled guns, was expected no earlier than September 1941. This relaxed state once again shows that self-propelled artillery was a low priority. This is strikingly different from the state of July 1941. During the first month of the war, several types of self-propelled guns were developed and even built, all of the light type. Just not at all what were originally planned. This was especially true for the ZIS-30, an initiative developed by the design bureau of plant No. 92. However, the most important point in this whole story lies in the general understanding of what kind of self-propelled artillery the Red Army needs. With some changes, but later the plan of the end of May 1941 became the very concept that was considered on April 14-15, 1942. The medium tank destroyer turned into a medium Sturmovik, the bunker fighter based on the 212 became an assault self-propelled gun based on the KV-7, and the light self-propelled gun base changed. But the general concept remained the same. In a word, work on self-propelled guns, which led to the creation of the SU-12 (SU-76), SU-35 (SU-122) and SU-14 (SU-152), did not begin suddenly. There are no miracles in these matters. Another question is that in the fall of 1942 the NKTP took up the matter, at the instigation of the State Defense Committee, this became the key to success.

List of sources:

1. RGVA
2. RGAE
3. TsAMO RF

source: https://zen.yandex.ru/media/yuripasholok/mechty-o-sovetskih-samohodah-letom-1941-goda-60df03b2baf4b439d3ba7395