Tanks at the Mannerheim Line

"Technical Meeting Minutes

Factory #185
May 9th, 1940
Chairman: comrade Barykov

Report by comrade Koloyev about the anti-tank defenses in the Summa region on the Karelian Isthmus.

The Mannerheim Line was built with the forces of four large capitalist nations. The Karelian Isthmus is bounded on two side by Lake Ladoga and the Bay of Finland, or to be more exact the Vyborg Bay. The isthmus, like all of Finland, is scarred by lakes, rivers, heights, and becomes one large foothold covered by a system of anti-tank fortifications. Let us examine one small region of the front line near Summa.

Damage to a KV Tank in Karelia

I talked about damage to KV tanks in 1940, but this is an even earlier case: December 1939, the very first KV that was sent into battle. Here is what Finnish AT guns managed to do to it.

1. Dent, 70 by 50 mm, 10 mm deep.

2. 100 by 50 mm dent, 10 mm deep.

3. 70 mm by 50 mm dent, 10 mm deep.

4. 60 mm by 50 mm dent, 10 mm deep.

5. The cap was knocked off and the bearing damaged.

World of Tanks History Section: SU-152, Soviet Beast-Killer

During the Soviet-Finnish War of 1939-1940, the Red Army hit a powerful defensive line in Karelia, the Mannerheim Line. Soviet soldiers were greeted with an unpleasant surprise: concrete pillboxes that could onl be destroyed with large caliber artillery.

Delivering a heavy and clumsy gun to a battlefield is not an easy task. The best solution is a gun that can drive into battle by itself. Soviet commanders remembered that work on self propelled artillery has been slowly coming along since 1931. The topic was dusted off. Two factories, Kirov and #185, got to work. By Spring of 1940, experimental vehicles have been designed: SU-14-2, T-100Y (SU-100Y), and KV-2, which may be called a tank, but was more of an assault gun with a turret. The SU-100Y did not make it in time for the war, but work on bunker busters continued. When the Great Patriotic War began, the design center was moved from Leningrad to Sverdlovsk.

From three barrels to one

The basis for the SU-100Y was the T-100 heavy tank, which lost out to the KV and did not enter production. This also put a cross over the SU-100Y. All heavy SPGs had to use the KV chassis.

In November of 1941, the Chelyabinsk Kirov Factory (ChKZ) designed the KV-7 assault tank, a vehicle with an immobile casemate carrying three guns. The project was curious, but its combat usefulness was doubtful. In fall of 1942, the Red Army GAU ordered ChKZ to develop a large caliber SPG, placing the ML-20 152 mm gun in the KV-7 hull. The project was headed by Lev Sergeevich Troyanov, the most experienced Soviet designer of SPGs.

Troyanov decided to install the casemate on a KV-1S heavy tank chassis. The wooden model and project documentation were ready at the end of 1942. In early January of 1943, the project was scheduled for a demonstration to the client. By this point, it was indexed KV-14. Two projects were demonstrated. First was designed by the factory #9 design bureau chief Fedor Fedorovich Petrov. The project was more complete, but needed many modifications of the KV-7 hull and the gun. Working blueprints for Troyanov's project were only partially complete, but his project required significantly less modifications to mass produced tanks and guns.

Stopping power

On the day after the demonstration, Joseph Stalin signed an order of the State Committee of Defense to build a prototype of the new SPG by January 31st, in less than a month. Kirov factory not only managed to deal with such a harsh quota, but finish a week early.

Trials of the new SPG were conducted from February 1st to February 5th. The KV-14 drove to the proving grounds at Chebarkul. This was a difficult trial: the SPG drove through a snowed-over highway in temperatures of -42 degrees. Water got in the engine, it kept stalling. The SPG travelled the 85 km from Chelyabinsk to Chebarkul in 13 hours.

After 234 shots, no defects were discovered in the gun or mount. The gun could not achieve the requested 3-4 RPM, but the result of 2.8 RPM was also not bad. No defects were found in the engine or transmission. There were design flaws that needed work, but by February 9th, the KV-14 was adopted into the Red Army.

And so, the USSR received an SPG with no equal anywhere in the world. It had a powerful gun, the armour of a heavy tank, and what was no less important for a fighting machine, a compact size. What's most important is that the Red Army received a universal SPG, capable of dealing with any combat mission. From the end of April of 1943, the vehicle was indexed SU-152.

The Beast-Slayer's debut was at the Battle of Kursk, in which 24 vehicles of this type took part. The small numbers did not make a large impact on the flow of events, but it turned out that, of all Soviet vehicles of the time, only a shot from this SPG could guarantee the destruction of any German vehicle of the time. It was not necessary for a 152 mm shell to penetrate enemy armour. Hero of the Soviet Union Major Sankovskiy demonstrated the combat potential of the SU-152: his vehicle destroyed 10 tanks in one battle.

The SU-152's effectiveness is also highlighted by the fact that it remained in service with Soviet tank forces until 1958.

Yuri Pasholok's book "SU-152 and other SPGs on the KV chassis" was referenced when writing this article.

Original article available here.

World of Tanks: Today in History: Karelian Offensive

The Soviet-Finnish War began on November 30th, 1939. The cause of the conflict was a territorial disagreement between the USSR and Finland, which could not be solved by diplomatic means.

The first stage of fighting proceeded poorly for the Red Army, mostly due to serious underestimation of the Finnish army's fighting ability, and due to the harsh terrain on which the Red Army had to fight. Many mistakes were made during planning, cooperation, and supply of advancing units.

On December 21st, the Soviet advance on Karelia completely halted. The Red Army fortified for a defense, collecting forces for a new offensive. During the relative quiet on the front, the Red Army analyzed its mistakes, reformed its units, and developed combat plans.

In December of 1939, during a breakthrough of the Hottinen fortified region, the famous KV-1 heavy tank saw its first combat trials.

The Red Army's offensive resumed on February 1st, 1940, with the forces of the recently created North-Western Front, commanded by S.K. Timoshenko. Infantry and tanks were supported by large amounts of artillery. Up to 12000 shells were launched towards Finnish positions daily.

The Red Army's general offensive began on the morning of February 11th, 1940, after a three hour artillery barrage. In three days, the Mannerheim line was penetrated, and tanks flowed into the breech. On February 17-23rd, the Finnish forces retreated to secondary defensive lines to preserve the front. Towards the end of February, the Red Army reached the rear of the Finnish positions, around Wyborg.

On March 13th, a peace treaty was signed between the USSR and Finland. This is the day that is considered the end of the Soviet-Finnish war in 1939-1940.

Original article available here.

Soviet Infantry Protection

Popular history treats Soviet infantry as expendables that overwhelm quality with quantity, but examination of actual historical evidence suggests otherwise. Attempts to lengthen the life of the regular soldier (or, in this case, policeman) predate the USSR, beginning with the Russian Empire. "A catalogue of armour invented by Lieutenant-Colonel Chemerzin" describes his inventions, dating back to 1905:

"The armours vary in mass, the lightest are 1.5 pounds, the heaviest are 8 pounds. They are unnoticeable under clothing. Anti-rifle bullet plates weigh 8 pounds. The plates cover the heart, lungs, stomach, sides, as well as the spine and back over the heart and lungs. Each plate is tested for impenetrability in front of the customer."

A little more on trials:

"In the presence of HIS IMPERIAL MAJESTY, on June 11th, 1905, in the city of Orienbaum, a company of machine gunners performed tests. 8 machine guns fired at a plate made from an alloy created by Lieutenant-Colonel Chemerzin, from a distance of 300 paces. It was hit 36 times. The plates were not penetrated, and did not crack. All non-permanent personnel of the infantry school were present."

The Moscow Capital Police, who ordered the armour in the first place, tested it at 15 paces, from unspecified arms. The performance proved exemplary: "[the armour plates] are impenetrable, and do not produce fragments. The first batch is satisfactory."

The St. Petersburg Capital Police report was more thorough: "The results of the trials were as follows: after firing at the front and back plates, one that weighed 4 pounds and 75 zolotniks [a zolotnik is 4.26 grams] and the other 5 pounds 18 zolotniks, composed of steel and wrapped in thin silk fabric, with a Browning bullet, the bullet penetrates the silk, and makes a dent in the plate, but does not penetrate it, and remains in between the silk and steel. No fragments of the bullet fly out."

The Ust-Izhor training proving grounds achieved positive results when testing the plates with "3 line rifles of the infantry type, from 200, 150, 100, 50, and 8 paces."

The archive file further mentions 4791 sets of body armour, 340 shields, and 200 helmets made of this alloy sent to the Warsaw fortress over the period of 3 months.

The invention made a mark on media. The "Rus" newspaper (#69, 1907) wrote: "I saw a miracle yesterday. A young man, thirty years of age, in a military uniform, stood still in a room. A Browning was pointed at him from half a pace, a frightening Browning, aimed right for the chest, for the heart. The young man waited, smiling. A shot struck, the bullet bounced off.
"See," said the military man. "I barely felt anything.""

"Novoye Vremya" wrote on February 28th, 1908: "The invincible armour and new breastplates are wonderful inventions of our century, and surpass the knight's armour of the past. The scale layers remain the same, but the alloy is different. It is the inventor's secret. A. A. Chemerzin only explained the main idea behind his discovery. A. A. Chemerzin is a Lieutenant-Colonel of engineering forces. He finished a degree in mathematics, then an engineering school. He taught mathematics, while studying chemistry, and a series of experiments led him to exploration of nickel-chromed steel. The alloy was created under high temperature and pressure. Precious metals like platinum, silver, iridium, vanadium, and many others were added to the mix. This led to a very ductile and strong metal, that is 3.5 times tougher than steel. As a result, at three paces, the Mauser bullet could not penetrate a half-millimeter plate. Armour and breastplates were made that were impenetrable for revolver and rifle bullets, which deformed without giving off fragments. The danger of concussions and ricochets was solved.
The armour is expensive, but life is costs more. Putting on the 5 pound armour that covers the front and back, I did not consider it heavy. It is entirely unnoticeable underneath a suit. 7000 breastplates, helmets, and shields were sent to the army in the Far East, but sadly, too late..."

Indeed, the invention did not come cheap. 1500-1900 rubles would buy you a standard set of armour. 5000-8000 could buy you a custom-made set, tailored to your body. Chemerzin also offered the armouring of a carriage (20,000 rubles) and a car's engine compartment (15,000).

In 1916, Chemerzin's armour was tested for pilots. While it performed admirably, a cheaper armour was chosen, manufactured at the Petrograd mechanical and metalworking factories.

I don't have anything about the interbellum period, but the question of protecting infantry was explored during the Winter War.

CAMD RF 81-12040-69

"In 1939, NKV NII-13 manufactured trial batches of steel SN-39 (150 units) breastplates and SNSh-39 (100 units ) breastplate-shields, which were then tested in combat (on Karelia). 

As is stated in our previous report for 1940 (report T-06-77), the breastplate received good reviews from the commanders of the 7th army, but the issue of increasing the strength of the armour in order to ensure bullet protection in close combat was raised. 

To resolve this issue, we have created a new (thickened) breastplate, SN-40A. According to the orders from GAU KA, a decision was made to mass produce the SN-40A, with the following goals in mind:

1. Manufacture 100-150 SN-40A breastplates, providing protection from model 1908 bullets fired from a rifle or machine gun from 150 meters at 0 degrees and from any distance at 30 degrees.
2. Manufacture the breastplates in three sizes. Previously, breastplates were produces in one size (small).
3. Explore the requirements for production of the breastplates and develop blueprints for equipment to mass produce the breastplates.
4. Conduct proving ground and battlefield trials to determine if the breastplates can be accepted by the Red Army.

The aforementioned mass production of the SN-40A is the topic of this report."

SN stands for Stalnoy Nagrudnik (steel breastplate). 

CAMD RF 81-12040-69

"The manufacturing of the SN-40A was done at the "Industria" factory in Lysva. The breastplates were produced in 3 sizes, and in two thicknesses and weights. The blueprints of the the breastplate are shown in figure 2."

Trials of the SN-40A were performed in the fall of 1941. The results were unsatisfactory. At 5.2 mm (one batch was 4.2 mm), the breastplates were too heavy. Even the air force did not want to use them. One would not immediately expect a heavy breastplate to matter in an airplane, but it does. "Uniform of the Russian Air Force 1935-1955" writes "The medical corps frequently equipped pilots with army type steel helmets. For example, in 1943, elements of the 4th Air Army made it mandatory for Il-2 and Pe-2 gunners to wear "a metallic helmet and special breast shields". However, in practice, when breaking away from a steep dive, the rear gunner was subjected to unacceptable forces, which lowered his capacity of defending the plane from enemy fighters." However, the specific breastplate in question was almost certainly not the SN-40A, but its successor, the SN-42.

The SN-42 was developed in the spring of 1942 and tested in August of the same year by airborne troops. It was composed of 36 SGN type steel, and was 2 mm thick. 500 units were manufactured, and sent to be tested in the army.

Overall view of the breastplate

Breastplate used as a shield

Breastplate used as a shield while prone

The results were as follows:

CAMD RF 81-12040-109

"In 1942, according to the orders from the GAU of the Red Army, the Scientific-Investigative Institute #13 of the USSR NKV, developed a steel breastplate 3.3 kg in mass, 2 mm thick, that protects the main organs of the human body against German submachineguns at all distances, and rifles and machineguns at 300 meters. 

According to GOKO order #2160ss from August 8th, 1942, the steel breastplates were sent to the army, and received positive reviews. The reviews mention the following:

1. The steel breastplates provide reliable protection from German submachineguns, as well as fragments of mines and hand grenades.
2. The maneuverability of soldiers with breastplates is almost unimpaired.
3. Aside from providing protection for the soldier, the breastplate also increases the soldier's morale when performing his duties.

The technical documentation on the steel breastplate was accepted by the GAU of the Red Army on August 7th, 1942, after which the breastplate was mass produced at factory #700 (city of Lysva). At this time, 85,000 breastplates have been produced, distributed as follows:

1. South-Western Front: 5,000
2. Stalingrad Front: 3,000
3. Leningrad Front: 1,000
4. Volhov Front: 1,000
5. Don Front: 5,000

70,000 units remain at the warehouse. "

The benefits of the SN-42 breastplate are outlined in more detail in a letter from the deputy commander of the artillery of the 68th Army to the head of the GAU KA, Major-General Hohlov.

CAMD RF 81-12040-109

"In November of 1942, the 57th army received 5000 steel breastplates to test. After the army established the reliability of the breastplates by shooting them from 100 meters with rifles, they issued a small amount (500 units) on a trial basis.
The breastplates were met with distrust, but commanders requested the breastplates in maximum available numbers after testing them in battle. All breastplates available in the warehouses were given out. In battles for Stalingrad, they were exhaustively tested.
Comments by unit commanders and soldiers say that the breastplate, in addition to the steel helmet, is a good and reliable method of protection from bayonets, bullets, and shrapnel.
It is also necessary to point out the morale value of the breastplate. Soldiers equipped with the breastplates that have experienced their reliability go into battle calmly and assuredly.
The artillery supply units are constantly receiving orders for additional breastplates. All these factors combined lead me to believe that the breastplates live up to expectations and are a worthwhile investment.
Please issue 15000 units to the 68th army."

Popular history dictates that only specially formed assault groups were equipped with SN-42 breastplates, but you may already be suspecting that it was not so. The breastplates were not meant for any one kind of soldier, as their instruction memorandum reveals:

CAMD RF 81-12040-69

"A memo on the use of SN-42 steel breastplates

1. The steel breastplate safeguards the chest and stomach of the soldier in combat from 1) bullets of a German submachinegun at any distance 2) bullets of rifles and machineguns at 300 meters 3) fragments of mines and grenades.
2. The steel breastplate, thanks to its construction, does not stifle the soldier's movement while walking, running, or crawling.
3. The breastplate weighs 3.3 kg. To maintain the soldier's endurance and maneuverability, the soldier must be lightened at the cost of his backpack load.
4. The breastplate can be used by:
1. scouts, out on a mission.
2. sappers, while out scouting, making breaches in barbed wire, defusing explosives under enemy fire, etc.
3. infantry teams during scouting by combat.
4. submachinegunners, sneaking through the enemy lines, riding as tank infantry, and laying in ambush.
5. assault teams, attacking a pillbox.
6. soldiers fighting in city streets.
7. communications personnel, checking and fixing telephone lines under enemy fire.
8. any other situation where the commander deems that the breastplates can be usefully applied.
5. The breastplate can be used in 3 ways.
1. The breastplate is attached using straps and covers the chest and stomach during movement.
2. When crawling, the breastplate can be used as a shield.
3. When removed, the breastplate can be used to cover other parts of the body (right side, left side, head).
6. The breastplate consists of:
1. a hull, with the upper and lower plates.
2. soft lining, attached to the hull with a snap pin.
3. belts for attaching the breastplate: one on the waist and two on the shoulder
7. The breastplates are made in three sizes. The breastplate is 2 mm thick.

The breastplates are handed out by the Front Commanders, and are to be used by those armies where they can be usefully applied. Army and Front Commanders should send their feedback on using the breastplates and suggestions to the General Staff of the Red Army, and send a copy to the GAU of the Red Army.

November 11th, 1942"

At the same time as the SN-42, the SShN-42 (steel shield-breastplate) was developed. 

CAMD RF 81-12040-69

The SShN-42 was thicker than the SN-42, at 4.9 mm. Only 25 SShN-42s were produced. The design passed trials, but their subsequent fate is unknown. Is is probable that they joined their regular breastplate cousins in the 5th Army for testing. 

CAMD RF 81-12040-69

In 1942, NII-48 developed its own batch of a spin on breastplates: bulletproof vests. The armour was composed of four plates: two in the front, and two in the back. The vest tied in the front with two bows, like a lifejacket. 

From minutes #215 section 40 of the Sverdlovsk Regional Committee, on August 30th, 1942 (TsDOOSO 4-18-15): 

"On the manufacturing of a trial batch of personal methods of protection for riflemen and machinegunners

The Regional Committee of the All-Union Communist Party of Bolsheviks approves of the initiative of the NII-48 in developing a design of personal armour protection and its mass production, and decrees that:

1. The director of the Uralmash factory comrade Muzrukov and director of NII-48 comrade Zavyalov must ensure the production of 200 units of personal armour and 50 units for personal armour for Maxim machinegunners by September 20th, 1942.
2. The VIZ director, comrade Radkevich, must provide to the Uralmash factory 3 tons of rolled 30 HGS steel for production of trial personal armour sets.
3. NII-48 director comrade Zavyalov is urged to manufacture a trial batch of armour sets and send them to the Red Army for practical tests. In the event that the tests pass and the armour is accepted for mass production, send the proposal to the Regional Committee.
4.  The General Secretary of the Sverdlovsk All-Union Communist Party of Bolsheviks must provide all necessary resources to factories in order to produce the personal amour sets for riflemen and machinegunners.

Regional committee secretary Andrianov"

500 vests were produced in total. They all were sent to the 5th Army, but did not saw very limited combat. It did, however, see enough that the Germans captured one unit.

"The picture was attached to a message from an intelligence officer in the headquarters of the German 35th Panzer division, informing the command of the 9th Army Corps that the enemy is using new defensive gear on October 2nd, 1942 called an "armoured vest", drawn based on an inspection of the unit captured during a battle."

The picture on the right is also of interest to us.

"Another picture from an intelligence officer in the 35th Panzer division, composed based on the statements of POWs from the 1158th regiment, which revealed that the regiment assault group used this second model of defensive gear on October 2nd, 1942, obtained with the purpose of evaluating its usefulness in battle. Based on the sketch, it was probably a prototype of the SN-42."

Based on reports from the front lines, NII-48 gave their bulleproof vest another try.

CAMD RF 81-12040-69

The change is pretty self-evident: two more plates were added to the front to protect more of the soldier's body. 

CAMD RF 81-12040-109

Here is another breastplate design, this one is a little different. Instead of one lower plate, there are three. The upper plate is composed of two pieces. The back also has a full shirt, not just straps. Its index was PZ-ZiF-20. As its name suggests, it was produced at the Frunze factory (#7). It did not perform as well as the SN-42, but was produced in large numbers anyway, as the army needed all the breastplates it could get. These breastplates were first issued in 1943. 

While the SN-42 was, no doubt, the best Soviet breastplate of the war, work did not stop with it. The financial plan for the second quarter of 1945 of the 6th Department of the Tank Directorate of GBTU KA (CAMD RF 38-11355-2756) mentions the following: 

"An experimental batch of bulletproof vests is being manufactured by the NKTP and NKLP factories. The vests are a new type of protection for Red Army soldiers. The contract is still being processed. The approximate cost is 500,000 rubles."

It is hard to judge how much 500,000 rubles is worth in today's money, but it is no small cost. For example, in 1941, developing the SPG-212 (more commonly known as Object 212) cost only 100,000 rubles. 

World of Tanks History Section: T-26

In 1929, the Red Army decided that the current armament of the RKKA does not meet the requirements of modern war. An independent solution of this problem was not possible at the time. Soviet engineers lacked experience, and the manufacturing base was weak. The only solution was to rely on foreign expertise.

In 1930, a delegation from the Directorate of Mechanization and Motorization of the RKKA, led by Innokentiy Halepskiy, bought a number of vehicles abroad, including tanks. One of these tanks was the British Vickers Mark E, more commonly known as "6-ton Vickers".

The British army was not interested in any modification of this tank. Not because the tank was bad. Military minds of Foggy Albion, let's just say, had an excessively creative approach to tank design. The 6-ton Vickers did not fit in their doctrine. The developers had to focus on marketing this tank externally.

The USSR purchased the two turret variant, armed with machine guns. These were named V-26, and did not cause much excitement in tank specialists. However, on January 8th, 1931, RKKA high command was introduced to the Vickers. They were in awe of the agility of this new tank, the ease with which they nearly flew across the proving grounds, leaped over trenches, and spun in place. The next day, Voroshilov ordered an immediate inquiry into the possibility of producing the V-26 domestically. A commission, led by S. Ginzburg, reported that the optimal solution would be to produce a "hybrid" vehicle, with some parts from the original replaced with those currently being developed for the T-19 tank. However, initial production started with no changes. Intelligence reported that Poland was ready to mass produce the 6-ton Vickers for its own army. These reports did not exactly correspond to reality, but orders are orders. The Vickers started production under the index T-26.

Manufacturing the T-26 was the job of the Bolshevik factory in Leningrad. The factory was loaded with other orders, but there was no other choice. The Stalingrad and Chelyabinsk factories were still being built. The head of production, and all further modernization, was the same S. Ginzburg.

Following the best traditions of the administrative bureaucracy, the initial order was for an incredibly unrealistic 500 T-26es by the end of 1931. Almost immediately, the order was reduced to 300, which was equally optimistic. The first half of 1931 was spend converting all blueprints to metric, prepare the manufacturing base, and create pre-production samples. This first stage was strictly closed to any changes, even if they clearly improved the design.

Soviet engineers successfully copied elements of the design. The ability of the elements once assembled, however, was limited. The 10 tanks that managed to leave the production line by summer were, at most, functional models. Their engines constantly broke down in the most creative and varying ways imaginable. The acceptable mode of operation allowed for 65% of engine parts to be discarded. Engines had mismatching dimensions, crumbling valves, the driveshaft was insufficiently hardened. Armoured hulls, released by the Izhor factory, had cracks in them. 10 mm of armour could be penetrated by a regular rifle bullet at 100-150 meters, which was considered impossible. Only by 1934, did the quality of the released vehicles drastically improve.

At first, the T-26 was produced with two turrets, located next to each other. This allowed the two gunners to fire in different directions at once, and was considered a good solution for an infantry support tank. As an alternative to a machine gun, is was possible to place a 37 mm cannon in one of the turrets.

In 1933, the T-26 underwent a change. Instead of two turrets, the tank got one, that could rotate in a full circle. The turret received a new 45 mm gun, which was superior to the 37 mm gun. Initially, all new tanks were to receive this upgrade, but due to deficits, both variants were produced until the end of 1933. The new gun and turret increased the weight of the tank, and a new engine and suspension had to be developed. The engineers did not reach great success here, and the tank became slower and more sluggish.

By the beginning of 1936, tank builders finally crossed out the half-track concept. The newly developed T-46 was too complicated and expensive. Work to modernize the T-26 had to be restarted. Bolted armour was replaced with welded, increasing its durability. The gun mantlet was altered, the fuel system was improved. The suspension was redesigned yet again. Due to new technology of electrical hardening, exceptional strength of the track links was achieved.

All of these modernizations could not hide the fact that, by the end of the 1930s, the T-26 no longer excelled in its category. Other countries had equal, or superior, tanks. An attempt was made to arm the tank with a 76 mm gun, but the project did not live long due to a manufacturing defect.

The first T-26es saw battle in the Spanish Civil War. Tanks supplied to the Republicans by the Soviet Union were used in nearly every operation, and performed admirably. A contribution to the T-26's status of a dangerous enemy was the fact that the German and Italian tanks that opposed it were only armed with machine guns. At the same time, the thin armour of the T-26 made it an easy target for AT guns. After evaluating the performance of the T-26, Soviet engineers installed additional armour screens.

Soviet tankers used the T-26 in the battle for lake Hasan. Due to incompetent commanders, many tanks were lost. During the assault on Zaozernaya hill, the tanks ran into a well prepared defensive line. Considering their weak armour, any frontal assault would lead to significant casualties. 85 tanks were destroyed, out of which, 9 burned. However, commanders reported a high survivability. A T-26 could withstand 5-6 Japanese shells. It's a shame that this quality had to be discovered in combat, and not on proving grounds.

In all conflicts the T-26 saw, its poor reliability shined through. Many vehicles were lost without participating in battle. During the Winter War, the Red Army lost 3178 tanks, 1275 of which were breakdowns. This war was difficult for all tanks. The terrain in most combat zones was poorly suited for armoured vehicles.

By June 22nd, 1941, 10 thousand T-26es of various types were in service. Its use in the first part of the war could only be described as a failure. The primary cause of low effectiveness of the T-26 was its obsolescence. The tank ceased to be exceptional in the 1930s. By 1941, it was weak. Its armour protected only from bullets. The weak engine did not provide a very high maneuverability. The poor reliability was another cause. A large number of vehicles was abandoned by their crews when there were not enough time or resources to repair them.

The second cause was the human factor. The level of commanders in the Red Army was quite low. Frequently, they had no idea how to use tanks correctly. Frontal assaults were deadly for the "cardboard" T-26. Instead of being used en masse, the tanks were subdivided up to individual vehicles. Coordination between units was lacking since there was no surplus of radios, and those that were available, were frequently poorly used. The situation with commanders' maps was a catastrophe. Frequently, hand-drawn diagrams were used. Even if the commander had a map, that didn't mean he knew how to use it. Reports and memoirs list many of these occurrences.

The combination of these two causes led to the destruction of most T-26es in the first 6 months of the Great Patriotic War.

The last operation T-26es were used in was the destruction of the Kwantung Army in 1945.

Original article available here.

World of Tanks History Section: KV-2

Combat experience of the experimental KV heavy tank in Karelia in December of 1939 showed that its armour held up very well against Finnish AT guns. However, the 76 mm gun was not powerful enough to combat concrete bunkers. The Military Committee of the North-Western Front sent a request to the Kirov factory: manufacture 4 KV tanks with a heavy gun, capable of destroying bunkers and anti-tank fortifications.


The project had to be developed quickly, since the Red Army was stuck on Finnish defenses. Engineers worked 18 hours a day, and finished the project in merely two weeks.

The new KV was armed with a 152 mm M-10 howitzer model 1938/40. It would never fit into the standard KV turret, and SKB-2's engineers created a large, rectangular turret for it. This turret, almost twice as large as the existing one, fit on the same turret ring.

The KVs were divided into two types. KVs armed with a 76 mm gun were officially named "tank with small turret". 152 mm howitzer armed KVs were called "tank with large turret". The KV-1 and KV-2 indexes we are used to were only assigned in 1941.

In February of 1940, these new tanks arrived in Karelia. They were put into a special heavy tank company under the command of captain Kolotushkin. Aside from the KVs, the company contained an experimental two-turreted T-100 tank. Unfortuntately, the KVs never got to test their might against Finnish fortifications. By the time they arrived, the Finnish defenses were overrun. Regardless, according to the KV crews, the new "heavyweights" destroyed 14 AT guns and 11 bunkers.

When shooting at granite-concrete anti-tank fortifications, it was found that if the fortification was not dug into the ground, it was simply flung to the side, or broken into pieces. This was still not enough to make a path, and sappers had to be called in.

Combat in December proved the KV's resistance to AT shells once again. Finns would often simply stop firing after several nonpenetrating hits. However, mines were a problem. As is proper for a breakthrough tank, the KV went first, and hit the minefield first. Damaged tracks and front wheels were common.

The Winter War showed many weaknesses of the KV-2 design. Their large mass caused them to sink in mud. The massive gun demanded that the KV-2 fired while stationary, hopefully on flat ground. Firing the 152mm howitzer during movement or while tilted could damage the tank. Furthermore, the small turret ring meant that shooting perpendicular to the hull was a bad idea. The turret might get jammed, or, even worse, the massive recoil would cause damage to the engine or transmission.

During the KV-2's lifetime, the production of sufficiently reliable parts. The gear box, in most cases, could not last the warranty period. Poor filters led to tanks breaking down after traveling on dusty roads. The cooling system worked poorly. The steering clutches broke constantly. No demands of the manufacturers could improve the situation.

The tank had poor visibility, and its large mass proved to be a problem not for it, but also for others. Not only was the KV limited in what terrain and bridges it could cross, but after passing through a road, it was often made unusable by wheeled vehicles.

By June 1941, 132 KV-2s were present in the Red Army. Only 20 of them could fight right away; the rest were either undergoing repairs or had no crews. A lack of experienced crews was a problem in general. The KV was a very different tank from a T-26 or a tankette, which many tank crewmen were trained on.

All of the drawbacks listed showed up at the start of the Great Patriotic War. They were further compounded by the lack of competent leadership. Commanders lacking battle experience often issued incorrect or contradicting orders. Tanks were often redirected, sometimes more than once per battle, which led to many pointless marches. KV tanks frequently broke down during these marches. If the tank broke down and there were no engineers nearby, it had to be abandoned, and, preferably, blown up. Even if there were engineers, the tank had to be towed. Damaged tanks were towed by Voroshilovets tractors. In the case of the KV, two tractors had to be used. One was simply not up to the task. During the first days of the war, the rapid advance of the German forces made evacuating tanks very difficult, and many were captured.

However, the KV-2 was not all bad. In the cases where KV-2s engaged the enemy, they could hold their own. Soviet heavy tanks were impervious to most of the Wehrmacht's AT guns, and one hit from the 152 mm howitzer was the end for any German tank. Numerous KV tanks, under enemy fire, calmly crossed into their positions, and simply ran over the AT guns. The same fate was in store for German tanks, especially light ones. KV tanks with experienced crews and competent commanders could deliver significant damage to the enemy. Sadly, in the first days of the war, there were very few of those.

KV-2 tanks stopped being produced in October of 1941. The reasons given were the technical problems with the vehicle, and the fact that the army had no need for a KV-2 at the start of the war. The 76 mm gun on the T-34 and KV-1 could do the job sufficiently well. Add to this the amount of materials that the KV-2 took, and this colossus was doomed to extinction.

The last KV-2 was used in combat during the Battle of Moscow in the 1941-42 winter. A turret from one tank outlasted the tank itself. It was mounted on the armoured train "For the Motherland", which fought in the southern direction until July 17, 1942, when it was destroyed by German bombers.

The only 100% authentic KV-2 is currently on display at the Central Museum of the Armed Forces in Moscow.


Original article available here.