Tuesday 31 March 2015

NKVD on Tank Use in the Winter War. Part 2: Vehicles

Part 1.

"Experience showed that the weakest point of existing tanks is their armour. 954 tanks were lost during the period of activity on the North-Western Front, which is over 50% of all losses in battle. Armour of T-28 tanks, not to mention BT and T-26 tanks, is easily penetrated by 37 mm shells. New KV and SMK tanks with 75 mm armour showed themselves well, as they were impenetrable by even 76 mm shells.

Another weakness of existing tanks was their off-road performance. They could not traverse the deep snow, 2-2.5 meter wide anti-tank trenches, escarpments 2.5 meters tall, or stone tank traps. All of these obstacles were impassable or difficult to cross without preparations.

Our experience showed that no tank type used its technically permissible speed. During regular marches, tank speed ranged between 15 and 20 kph, on the battlefield, between 6-10 kph.

Therefore, the experience of war requires that we immediately review current tank designs. First, we need to produce armour screens that proved themselves well in battle for existing tanks to make them immune to 37-45 mm shells. According to specialists, our army needs the following types of tanks, based on the experience of the Finnish theater:
  1. A tank for maneuver action with 25-30 mm of armour and a top speed of 35-50 kph.
  2. An infantry tank for cooperation with infantry when penetrating field fortification, with 60-70 mm of armour that is immune to low caliber shells, with a top speed of 25-35 kph. An up-armoured T-28 or T-35 tank would work for this role. Such a tank would neutralize artillery up to 76 mm, forcing the enemy to use only medium calibers, which will require special measures to camouflage and hide on the battlefield due to their large size.
  3. A breakthrough tank with armour up to 100 mm and a top speed of 25 kph. This tank needs to be even more powerful than the infantry tank to operate in fortified regions with mine fields, tank traps, wide trenches, and pillboxes. Its armour must resist 76 mm guns and armament must be able to destroy pillboxes (122-152 mm). The tank would weigh 40-60 tons and be able to cross 6 meter wide trenches. Its average speed can be 10-20 kph, and top speed 20-30 kph.
    Success in the use of KV and SMK tanks shows that our designers and factories are capable of giving us such a tank.
Other defects in the design of vehicles include a poor radio design, which is large, non-portable, requires concentration for configuration work, and, mainly, cannot be used without turning away from the tank's weapons. As a result, commanders often forgot about their radio in situations where they needed to not only observe and control their unit, but fire from their tank.

The tank machinegun also performed poorly in battle. Disk magazines often jammed. Tanks require an improved machinegun."

Monday 30 March 2015

NKVD on Tank Use in the Winter War. Part 1: Tactics

"April 5th, 1940

To the chief of the Special Department of the NKVD GUGB, Commissar of State Security 3rd Rank, comrade Bochkov

Report on the deficiencies in units during the period of combat against White Finns (based on materials of special units).

Deficiencies of motorized units in combat

The specifics of the Finnish theater of war did not allow for the deployment of large independent tank units for powerful frontal or flanking attacks against the defending enemy. Tanks fought primarily in small groups with infantry, mainly along roads. Despite this, tanks played a significant role in the combat operations of the Red Army, especially on the Karelian Isthmus, where the main armoured forces were concentrated. During the war, a series of serious drawbacks was discovered among tank forces, which increased the difficulty of armoured warfare in the Finnish theater. The main drawbacks were lack of cooperation with infantry, artillery, and other types of forces, defects in the design of tanks, and deficiencies in the organization of armoured forces.

The specifics of the Finnish theater demanded that tanks must cooperate closely with other types of forces. However, in practice, tanks cooperated little. The cooperation with artillery and infantry was especially deficient.

The commanders of infantry units, regiments and battalions, did not always give clear objectives to the tank units that were assigned to them. Sometimes, commanders lacked significant knowledge of enemy defenses due to weak reconnaissance, and gave orders based not on specific targets designed to suppress specific enemy strongholds, but by lines on a map or landmarks. The path for tanks was often not specified, and was not supported with reconnaissance or infantry support.

In the 39th Light Tank Brigade, as a result of insufficient cooperation with infantry during combat on December 15th, 16th, and 17th, only 34 tanks returned out of 62 tanks that participated in combat. Of those, 5 were burned up by the enemy, 6 were stuck in an anti-tank trench, and the fate of the remaining 23 is unknown. 19 men from the crews died, 23 were wounded, and 32 disappeared. 5 of the dead were company commanders.

The operation started with no reconnaissance, tanks knew about only one trench, but not about the second one. The task of setting up a passage across the trench fell to the sapper battalion of the 49th infantry division and the brigade's sapper company, but the passages were made inattentively and the tanks had difficulty crossing. On December 15th, the 222nd Infantry Regiment that was supposed to support the tank attack at 12:00 was on a lunch break.

Tank units did not get their assignments in time, which made fulfilling orders impossible. On December 18th, 1939, at 12:00, the commander of the 768th Infantry Regiment Major Sokolov arrives at the preliminary positions of the 1st tank company of the 108th Independent Tank Brigade, and ordered Lieutenant Gaitsin on behalf of Brigade Commander Pestrevich: "You are now subordinate to the commander of the 554th infantry regiment. Attack now, as the main attack will start after the artillery barrage at 13:00". One hour remained until the attack, necessary to move into position. When the company arrived at new positions, the commander of the 554th regiment ordered "Attack immediately over there (waved his hand) or the regiment's attack will be late" instead of giving specific orders. When company commander Gaitsin asked for a more specific task, the commander replied "If you do not wish to attack, I will report you to the division commander." As a result, tanks attacked with no infantry. They drove up to the tank traps, found nothing, and drove back.

This situation with cooperation persisted not only in the first period of fighting, during assaults on a fortified region, but after, during the breakthrough and general offensive. Three battalions from the 13th Brigade accompanied by two regiments of the 84th Infantry Division penetrated from the Kamara station to the South-Western ourskirts of Pien-Pero, where they fortified for a defense for three days. Due to a lack of cooperation with neighbours, there was no connection to the rear (tank traps region between Kamara and Pien-Pero). The brigade commanders made no effort to establish cooperation and communication with their rear. Instead, an order was given by radio on February 22nd to attack Pero station without any directions on cooperation with neightbours, no communcation with the rear, and, most importantly, no communication with artillery of the 84th Infantry Division, which remained in the rear, cut off from the enemy. As a result of a lack of cooperation and reconnaissance, combat operations were carried out with great losses, and not always successfully, which is especially confirmed by experience in the February-March battles of the 20th Tank Brigade, which lost 68 tanks from enemy fire, 49 from mines, 3 in swamps, 3 to fire, and 6 were left on the battlefield in February. In total, 55 tanks were lost due to technical reasons.

On March 2nd, 1940, the 95th Independent Tank Battalion of the 20th Brigade was attached to the 201st regiment of the 84th division and tasked with capturing the railroad platform West of Wyborg near height 36,5 and Nameless (map 50000). When the order was given, Colonel Sinenko, HQ chief in the 20th Brigade, did not give an order for reconnaissance. The battalion performed its task without reconnaissance, infantry riding on top of tanks. As a result, the infantry was destroyed by flamethrower and machinegun fire on and around the tanks, while 3 tanks were destroyed by AT guns and 8 tankers were killed.

On March 5th, 1940, at 7:00, the HQ of the 20th Brigade received an order to capture heights 38 and Nameless, ending up at the bridge North-West of Yutnai. The HQ chief wrote an order for the 90th Independent Tank Battalion to attack in the first echelon, and the 95th battalion in the second echelon with elements of the 84th division. The division and brigade commanders did not think the offensive through, and the HQ chief did not check the preparedness of the battalions. As a result, it was only discovered during the offensive that the 90th battalion is not prepared for battle. The brigade commander ordered the 95th battalion, already prepared for a combat mission, to immediately perform the mission of the 90th battalion. The battalion commander was told that he would discover his objectives from the 344th Infantry Regiment. The 95th battalion was supposed to gather up in 10 minutes and go into battle without an objective. Only at the start of the battle did the battalion commander familiarize himself with the order of the 344th regiment, and did not manage to familiarize himself with the orders of the artillery commanders. The attack was planned for 12:00, an artillery barrage was fired, but nobody ended up attacking.

The brigade commanders did not concern themselves with issues of reconnaissance, electing to follow the very general, not always correct, and unconfirmed information of infantry reconnaissance, which was not always suitable for tank units. The 215th Reconnaissance Company, attached to the 20th Tank Brigade, was not used for its intended purpose during the war, and received no orders to discover the location of the enemy. In combat, the reconnaissance company did not perform reconnaissance, but was instead used as a means of communicating with neighbouring units, with the exception of 2-3 tanks observing the battlefield.

Other brigades were in similar shape. On March 12th, the 1st Battalion of the 1st Brigade received an order to support the success of the 613th Infantry Regiment, which was tasked with capturing Tammisuo. The battalion could not complete the task due to a lack of knowledge about enemy anti-tank defenses and their route. A part of the tanks got lost and stuck in traffic jams under enemy fire, a part hit a minefield and barricades, and also stopped under heavy fire. The battalion, without completing its objective, lost two men killed, three men wounded, and two tanks knocked out. The 1st Tank Brigade lost 13 tanks in total during the war due to not knowing combat routes and weakness of infantry and tank reconnaissance.

In several cases, infantry did not follow tanks, and did not fortify the areas they captured, leaving tanks to fight AT guns, mortars, and anti-tank riflemen groups alone. On December 17th, 1939, 20th Tank Brigade Commander Barzilov ordered the 95th Tank Battalion to capture Hotinen-Turta, assisted by the 768th regiment of the 138th Infantry Division. Just before the offensive, a message came in from the commander of the 138th Infantry Division HQ, Colonel Bashin, saying that there will be no artillery barrage, as the enemy is on the run, infantry is already in Hotinen and is attacking Turta. Due to this, it was proposed that the battalion goes further past the Summa fortifications, clear the path for the 10th Tank Corps to Wyborg, and follow them.

However, information about Hotinen was incorrect. When the 95th battalion approached the first line of tank traps, it was discovered that they were not destroyed, were followed by minefields, an anti-tank trench, and a second row of tank traps. There were no infantry units from the 138th Infantry Division. When the battalion approached the tank traps, they came under a hurricane of artillery and machinegun fire, and two vehicles were knocked out. The battalion entered battle, crossed the first row of tank traps, but was unable to cross the second due to an artillery barrage, and, without assistance from infantry or artillery of the 138th Infantry Division, were forced to retreat to initial positions.

The 91st battalion of the same brigade suffered a similar fate. It also ran into anti-tank obstacles and was forced to retreat, as elements of the 255th and 272nd infantry regiments lagged 1-2 km behind the tanks and did not go for an attack.

These problems with cooperation happened in later battles as well. On March 7th, 1940, at 16:00, the reconnaissance battalion of the 1st brigade received an order to take the roads in the Kongas region on March 8th, in cooperation with the 331st and 335th Infantry Regiments of the 100th division. The chief of the 1st unit of the division was supposed to direct this operation, but when the representative of the battalion arrived at the divisional HQ, he could not find him. The remaining commanders knew nothing of the offensive. Representatives that attempted to make contact with the individual battalions of the 331st regiment barely found them, as not all battalion commanders knew the exact location of their units.

Nobody in the 335th regiment knew anything about the offensive when contact was made at 01:00 (the order arrived at 02:00). Naturally, the regiments had no success when carrying out the operation, as they acted in an unsynchronized manner and did not advance simultaneously. The 331st regiment started retreating from the railroad and asked the regiment to provide artillery fire at the tank traps, not informing the reconnaissance company commander, whose tanks was currently at the tank traps. As a result, the reconnaissance company and the attached infantry from the 167th Motorized Infantry Battalion took casualties from their own artillery (up to 50 men killed and injured).

Cooperation between artillery and tanks was not always at the required standard. Communication between artillery and tanks, as a rule, was absent. Artillery mainly provided tanks with a passage through only the first row of anti-tank obstacles. In depth, the tanks were left to fend for themselves and received no support from artillery.

Regimental artillery was often late in reaching positions for direct fire support, or was used to fire indirectly. AT guns of advancing infantry were almost never used. Artillery largely shot at areas, and tanks could rarely summon quick fire from divisional artillery to destroy enemy AT guns.

The lack of cooperation between moto-mechanized forces and other kinds of forces, especially artillery and infantry, led to failures to achieve objectives and excessive losses. Frequently this resulted in shelling of our own forces. The above leads to the conclusions that the issue of cooperation was not given its deserved attention during peacetime. This was especially noticeable when attacking enemy fortifications, when it became necessary to hold training exercises between operations to teach various kinds of forces how to cooperate in battle. Unfortunately, these exercises had little effect, as they were very hurriedly prepared."

Continued in part 2.

Sunday 29 March 2015

Tiger II Trials: Ergonomics

The Soviet trials of the Tiger II, among other things, covered the comfort of the crew inside the tank.

"Evaluation of the workspace

The tank commander is placed in the fighting compartment (turret) to the left of the gun, behind the gunner. The tank commander controls the crew with the intercom or his voice, observes the battlefield, and corrects fire.
The commander's workspace is insufficiently comfortable. The footrest is positioned too high up in relation to the seat. The seat is fixed in height, and the observation devices are too high, forcing the commander to lift himself up in an inconvenient way to use them.
The observation devices placed in the commander's cupola provide the ability to observe a 360 degree zone. It is possible to observe terrain 1500 meters away from the observation devices.
Discovery of targets and fire correction is done through the fire correction scope at up to 3000 meters.

The gunner is placed to the left of the gun, in front of the tank commander, near the aiming mechanisms and sight. The position of the sight, aiming mechanisms, and seat is satisfactory. The hydraulic and manual turning mechanisms are convenient to use. The elevation mechanism, placed under the oscillating part of the gun is satisfactory. At elevations of +10 and higher, the position of the gun cradle impedes normal work.
Firing in place is possible and convenient when working with either traverse mechanism using the electric trigger positioned on the handle of the elevation flywheel. When firing on the move, it is much easier to use the hydraulic turning mechanism that can be operated with one's legs, and use one hand to turn the elevation flywheel and another to fire. Both left and right hands only perform one function, which increases the aiming speed and increases the effectiveness of firing from the move.

The loader is placed in the turret, to the right of the gun. The loader's seat is well placed, and its ball mount means it can be easily stowed aside to make room for the loader. The loader's workspace allows for rapid and convenient loading of the gun.
Loading of the gun is eased with the presence of a roller, placed in the turret bustle in such a way that it can be used at any position of the turret.
Taking shells from the rack on the right side of the hull is easy at angles of 0 degrees, 90 degrees and -90 degrees, but inconvenient at 180 degrees.
Taking shells from the rack on the left side of the hull is easy at angles of 180 degrees, 90 degrees and -90 degrees, but inconvenient at 0 degrees. The brass catcher and guard are well placed.
The visibility through the loader's periscope is insufficient.

The radio operator is placed in a seat in the right half of the driver's compartment. The radio station is placed in a special frame on top of the gearbox. The dimensions of the radio operator's workplace are sufficient to allow work with the radio station and firing the machinegun.

The driver is placed in a seat in the left half of the driver's compartment. The seat has two fixed positions. The tank can be driven with a closed hatch and an open hatch. In the latter case, the driver's seat can be lifted up. The steering wheel and accelerator pedal also have an upper position.

...

The concentrations of fumes in the fighting compartment are as follows:

Type of ventilation
# of shots
Time spent shooting (sec)
Concentration of CO in mg/L
Reduction of CO compared to no ventilation
None
5
65
3.65
0%
Working engine
5
62
2.53
30.%
Engine and bore evacuator
5
57
1.81
50.5%
Fan
5
55
1.12
69.5%
Engine, fan, and bore evacuator
5
59
0.15
95.9%

The ventilation only provides satisfactory working conditions if all are working at once. Excluding any one of them raises the fumes to unacceptable levels (over 0.4 mg/L). The most powerful ventilation system component is the fan placed above the gun breech."

CAMD RF 38-11355-2860

Friday 27 March 2015

SU-85 vs Tigers

We've seen what SU-85s can do against Tigers in controlled conditions, but of course, theory and practice are often at odds with one another. Here's one situation where the two met on the field of battle.

"In battle with German invaders, comrade [Petr Yermolayevich] Osminin showed unliimited devotion to the principles of the party of Lenin and Stalin and his socialist Motherland.
He displayed a feat of heroism, courage, and bravery during a German counterattack against the left flank of the 2nd Motorized Infantry Battalion near the Suostai village on August 7th, 1944. As a driver of an SPG, he was one of the first to take his crew to face the enemy, who fired upon enemy Tigers and Ferdinands to prevent them from attacking the left flank of our units.
In this battle, the SPG destroyed the following: 1 Tiger tank, 5 anti-tank guns, 1 StuG and up to 30 soldiers and officers. In this uneven battle, as a true patriot, engulfed in flames but fighting until his last breath, he died the death of heroes.
He is worthy of the title of Hero of the Soviet Union, posthumously."

CAMD RF 33-793756-35

Another award order to the gunner (Nikolai Ivanovich Petrov) exists in CAMD with mostly the same text.

I doubt that there were actual Ferdinands, especially since a knocked out StuG is reported. As always, let's see what Schneider has to say about this.

"7 August 1944: In the morning the battalion is ordered to attack to the south from Kacenai to Bobenai despite an enemy penetration near Suostas. Contrary to the recommendations ofthe battalion, the useless attack against Bobenai is continued. When Bolter (4 Tigers) is finally directed to Suostas at mid-day, the German infantry is already retreating. After fierce fighting, Suostas is taken back (4 tanks and 3 antitank guns knocked out, including one captured German 8.8-centimeter Pak, which knocked out 2 Tigers). After dusk, the 81. Infanterie-Division withdraws behind the Memel sector to Struski (4 kilometers north of Schonberg) under cover of the Tigers."

Just as I thought, the "Ferdinands" were actually StuGs from 81st Infantry Division. In a similar case of misidentification, it's likely that the "captured 8.8 cm Pak" was the SU-85 that ended up knocked out, as the Germans didn't claim any SPGs.

Thursday 26 March 2015

World of Tanks History Section: Tanks in the Spanish Civil War

In 1936, a civil war erupted in Spain between the Republicans and Nationalists, those that backed General Franco. During this conflict, the country was a proving grounds of sorts, a place where new weapons were tested and new tactics were developed. Of course, things did not progress without tanks. Republican Spain received over 300 T-26 and BT-5 tanks from the USSR, and the Nationalists were reinforced with German PzI and Italian CV 35 tanks.

Spanish "Firefighters"

Spain is a very unique country, with many escarpments and highlands, separating it into half-isolated regions. In order to transport tanks in between battles, the Republicans actively used powerful German and American trucks. They had to be careful, as a deviation of several centimeters on the narrow mountain roads meant certain death. The risk gave a return, however, as tanks could be transported over 400 km in less than a day.

This was very important for the Republican army, which had to constantly plug holes in its front lines during Nationalist offensives. Tanks were used for this purpose, and could stay in battle for days. Crews were exhausted to their limits. Eyewitnesses record nervous breakdowns and hallucinations.

The tankers' courage was great: they attacked 10-15 times per day, fought with broken ribs, with burns and wounds. If necessary, they fought in tanks with holes in their armour. When it was necessary to replace a dead or disabled tanker, any soldier would do as a replacement. The crew would explain to him how to load the gun on the way to battle, and that was the end of training.

In these conditions, there was no cooperation among the tanks or with any other types of forces. In Spain, tanks fought in small groups, or even individually, without complicated maneuvers, firing their cannon at all targets. The tanks fired while stationary, as it was easier to hit that way. The crews didn't conserve ammunition; tanks shot up to 7 loads of AP shells per day. They weren't spared even when shooting at machineguns, as the precision of the T-26's gun allowed them to hit even small targets.

Local War School

Cooperation was a serious problem for the Republican army. In theory, tanks were to follow infantry, and when it arrived at the enemy lines, overtake it, attack the enemy, and again back out behind their infantry. In practice, tankers always complained about infantry that was "lying around sightseeing" instead of fighting.

Reconnaissance was also poor. At best, tankers knew the direction the enemy is in. Terrain was not observed, and tanks went into battle blind.

The Nationalists, on the other hand, fought in a more organized fashion. At first, defenders were "worked over" with bombs or artillery. Then, tanks with infantry attacked. Even well trained foreign volunteers (interbrigades) could not withstand such an attack. When the Nationalists captured even a scrap of land, they would dig in, and concrete fortifications would appear within two or three days. Artillery followed close behind infantry.

The T-26 was rightfully called the main strike force of the Republican army, equal to its aircraft. It was praised for its accurate and reliable gun, reliable engine, and respectable speed. The engines worked fro 100-150 hours, even in cases where they ran for nearly a whole day straight with no complaints. In tank on tank battles, German PzIs and Italian CV 35s were no match for the T-26. They were frequently referred to as tankettes instead of real tanks. This experience caused machinegun tanks to disappear quickly.

From a purely technical point of view, the Republicans surpassed the Nationalists. However, the latter fought these tanks even when they had no anti-tank guns. Improvised measures such as petrol bombs or barrels of sap dug into the ground were used.

Crews quickly learned to shoot off balconies where petrol bombs were thrown from. However, it was still hard to fight in populated areas. The enemy could be anywhere, and spotting him from inside the vehicle was a tough job. To make matters worse, Spanish settlements were built like miniature fortresses for centuries, with narrow winding streets, dead ends, and squares that were open from all sides. Walls could have houses with walls up to 2 meters thick, and 4 meter tall stone walls were common. After the first few fights, tanks were forbidden from entering towns, and ordered to surround them and shoot from a safe distance.

Armour lost to the shell

The main enemy of tanks in Spain were anti-tank guns. They appeared during WWI, but became very common in the 1930s. The USSR already developed methods of fighting them, and instructed Spanish tankers, but spotting a stout 37 mm gun from a T-26 was hard. Considering that the armour could be penetrated from 200-300 meters by an armour piercing bullet, the fate of a tank hit by a shell was not enviable. The Nationalists got more and more guns, and it was more and more important to find them.

The use of anti-tank guns in the Spanish Civil War put an end to tankette development and led to the appearance of tanks with shellproof armour. The idea of putting armour at an angle to ricochet shells was also born. An understanding evolved that tanks need improved optics so they could see better.

Only a short time remained before tanks built based on the experience in Spain would be tested by a large war.

Article author: Evgeniy Belash

Original article available here.

Wednesday 25 March 2015

Beyond Armour Effects

I previously showed that 50 mm APCR did little damage to the components and crew of a Valentine tank after penetration. But how does APCR perform in general? B.M. Bakshinov, S.V. Lomov, and V.I. Timokhin decided to try it out.

"The main cause of damage when penetrating armour is a stream of fragments. The subcaliber armour piercing shell generates the most fragments, and its parameters are used to determine performance of crew protection measures. However, it is not enough to determine the damage caused by homogeneous steel subcaliber ammunition, since modern foreign subcaliber shells use casings from heavier metals (tungsten, nickel, iron, etc).

An experiment was carried out to determine behind-armour effect of the domestic equivalent. A "sieve" type target made up of two aluminium plates 3 mm each and a steel plate 8-10 mm thick was placed 0.5-1 meter behind 70-220 mm of medium hardness steel. The angle of obliquity was set to 60 degrees from normal, velocity was set to match a range of 2 kilometers. The number of fragments that penetrated the sieve was recorded, as well as their spread from the central axis.

The experiment allowed the formulation of conclusions on behind-armour effect of subcaliber shells:
  1. Two groups of fragments are generated, differing vastly in penetrating power and number.
  2. As excess penetration grows, the number of lethal fragments increases sharply, and then stabilizes.
  3. The angle of dispersion weakly correlates with excess penetration.
  4. There is a limited number of fragments capable of penetrating 30 mm of aluminium at a small spread. As excess penetration grows, their spread decreases.
  5. Most fragments cannot penetrate more than 20-25 mm of aluminium."
Fig 1. Parameters of behind-armour effect of a heavy alloy subcaliber shell. Number of lethal fragments vs: a) their angle of spread, b) in proportion to excess penetration, d) angle of aluminium penetrating fragments and d) penetration of aluminium. Empty shapes are data points, dark shapes and lines are interpolations.

Fig. 2. Fragment spread with 180 mm of excess penetration. The penetration of the fragment is proportional to the length of the cone that represents its group, to scale.

A comparison is also made with effectiveness of domestic shells.


Shell
Fragments capable of penetrating 3-6 mm of aluminium
Fragments capable of penetrating at least 30 mm of aluminium
Number
Angle of spread
Number
Angle of spread
With excess penetration of 100-200 mm
Heavy alloy
200-300
100
7
20-30
3BM9
200-300
100-120
2-3
20-30
3BM15
150-200
110
2
20
With excess penetration of 250-300 mm
Heavy alloy
300-400
100
20-25
12
3BM22
200-300
100
20
24
3BM26
200-300
120
37
32

The article also gives some details on the shell compositions. 3BM9 has an all steel case, 3BM15 has a front heavy alloy core, and 3BM22 and 3BM26 have a heavy alloy core in the rear. The paper reveals that in the latter cases, the fins of the shell and core fragment after they enter the armour, creating more lethal fragments and resulting in a larger angle of spread.

Tuesday 24 March 2015

King of the Hill

"Award Order
  1. Name: Pateev, Nikolai Pavlovich
  2. Rank: Lieutenant
  3. Position, unit: T-34 company commander, 326th Tank Battalion, 11th Tank Unecha Brigade, 1st Tank Corps
    is nominated for the title of Hero of the Soviet Union.
  4. Year of birth: 1919
  5. Nationality: Russian
  6. Party affiliation: VKP(b) member since 1943, party membership #6463036
  7. Participation in the Civil War and subsequent conflicts in defense of the Soviet Union: Patriotic War since June 26th, 1941: North-Western Front, Stalingrad Front, Bryansk Front, 1st Baltic Front.
  8. Wounds or concussions: lightly wounded on February 11th, 1941 (North-Western Front), lightly wounded on September 25th, 1943 (Bryansk Front).
  9. In the Red Army since: 1939
  10. Recruited by: Oktyabr recruitment office, Leningrad
  11. Prior awards: Order of the Red Star by order #015/N on October 15th, 1943 to the 117th Tank Brigade, Order of the Patriotic War 1st Class by order #019/N on July 19th, 1944 to the 1st Tank Corps.
Brief and specific description of heroism: Having concentrated a significant amount of tanks and infantry, with artillery support, Germans attacked West of Dobele on September 17th, 1944. Lieutenant Pateev's tank company was tasked with forming a defense at height 91,7 and Kristichi, stopping the enemy there. The courageous officer quickly judged the situation, placed his tanks, and gave an order: die before you let even a single enemy tank through.

On September 18th, 1944, 30 enemy tanks supported by artillery attacked our tanks. Despite the difficult situation, our tanks let them approach to a short distance and shot them up at close range. Over 4 days, the company deflected 28 attacks, destroyed and knocked out 37 tanks and up to 400 fascists. The enemy was taking heavy losses attempting up to 13 attacks per day, but the bloodied company would not take one step back and continued to perform their duty.

On September 19th, 1944, 10 enemy tanks broke through around height 91,7, including 3 Tiger tanks. The fearless officer did not think long before entering an uneven fight with no artillery support.

Skilfully maneuvering his tank, he quickly chose positions and destroyed attacking tanks. As a result of the battle, the crew destroyed 7 PzIV tanks and 2 Tiger tanks. The remaining tank retreated, but was knocked out by other tanks from the company.

For excellent command of his company and personal stubbornness, courage, bravery and heroism, comrade Pateev is worthy of a government award" the title of "Hero of the Soviet Union".

Commander of the 326th Tank Battalion, Senior Lieutenant Kozhikhin"

CAMD RF 33-793756-36

What a defense! You can tell that even before this, the unit did not have an easy time. The company, normally commanded by a Captain, is in the hands of a Lieutenant, a whole two rank levels lower. Similarly, a Major's seat at the head of the battalion is occupied by a Senior Lieutenant.

Let's take a look at who those Tigers belonged to. s.Pz.Abt 502 was currently in the area. Here is what their combat diary contains:

"1 September 1944: 19 tanks operational.
In the weeks that follow, the tanks are employed dispersed all along the Riga Front.
14 September 1944: During the ensuing Soviet offensive against RIGA, there is fierce
fighting, resulting in 6 total losses.
Total tanks: 21
26 September 1944: The battalion destroys its 1,000th tank."

Not particularly descriptive. Since the battalion was separated, its diary was not being well maintained. Unfortunately, the bragging a week after this battle doesn't tell us what happened, but at the very least we know that Tigers were indeed employed piecemeal and seeing 3 Tigers in the company of PzIVs is very possible. Seeing as how s.Pz.Abt 502 is soon recalled to be re-equipped with Tiger II tanks, I'm going to say that they were soundly beaten in the Riga Offensive Operation and the destruction of three Tigers by Pateev's company is very feasible.

Monday 23 March 2015

M2A2 Tanks in the Antarctic

"Excerpts from the assistant USSR military attache in the USA, Major Barayev.

Performance of American M2A2 light tanks in the southern polar territories (Antarctica) according to the American Antarctic expedition.

1. Reduction of tank weight.

Before tanks were sent to the polar expedition, it was decided that they should be lightened. All armament and a part of the armour was removed. When tanks arrived to the polar stations, it was determined that they were still too heavy to work in the icy conditions of the Antarctic. Turrets were removed in order to increase power per ton and improve stability.

The tank ground pressure was reduced to 5 or 6 psi. This was still not ideal, as previous experience in soft snow showed that the ideal value is 4 psi.

2. Power.

In order to increase the tank's power when moving on soft snow and reduce instances of falling through, additional plates made from 1/4 inch thick armour taken from the turret were welded to the tracks. The width of the plates was 8 inches, and they increased the width of the track by 7 inches, to a total width of 11 inches. These plates were welded on the inside of the tracks. This improvement increased the tank's power and protected it from falling through the snow.

3. Controlling the tank.

When the tank moved across loose snow, the snow was thrown up and blocked the driver's viewport. This was resolved by installing a protective plate, a regular automotive fender. It is necessary to install a special de-icing attachment to the glass window on the driver's viewport. The Antarctic service could investigate this issue, but it is preferable if the Army took it upon itself to solve it.

4. Carburettor.

The carburettors didn't have any problems in the cold. They worked normally, but it was assumed that all gasoline had to be filtered through suede to prevent water from getting into the carburettor.

The fuel line to the carburettor runs next to the engine, so the gasoline that goes through it is heated up by the engine's heat.

It is recommended that the fuel tank should be insulated, preventing excessive freezing.

5. Air filter.

Difficulties were encountered with the air filter when it was frozen. Freezing stopped the air from being sucked in and destroyed the pipe to the carburettor. In order to prevent this rubber pipe from rupturing, it is recommended to use a metal pipe. In the end, the air filter was thrown out entirely, as there is no need for it in the polar atmosphere with no mud or dust.

The pipe was replaced with one leading to the engine compartment near the batteries, where air was gathered without any filter.

6. Batteries.

The batteries worked well in cold conditions and no difficulties were encountered. Nevertheless, it is recommended to add a special insulation layer around the battery crates, considering that drafts are formed in this compartment once the air intake pipe is routed here.

7. Oil filter.

Like the air filter, the oil filter is completely unnecessary in polar conditions. In practice, the oil froze in it and caused it to rupture. The expedition removed all oil filters after a series of such cases.

8. Heating the engine.

The last two American expeditions to the Antarctic used Van Pregg heaters to heat up engines. They worked well for heating aircraft engines, but the best heater for tank engines turned out to be the Primus heater. This heater is made in Sweden in two sizes: 3 gallons and 5 gallons. It can keep the temperature of the engine compartment, and thus the motor, to 50 degrees Fahrenheit. Heated air is channeled into the engine compartment through a hose into an area with no electric wiring or fuel lines.

Oil is heated to a temperature of 120 degrees in special tanks with the same heaters. After being heated, the oil is poured into the crankcase and the engine starts. The engine can start at a temperature of 50 degrees, but before moving the tank, the engine temperature is increased to 100 degrees.

During Antarctic expeditions, it was determined that it takes about one hour to heat up the engine to 50 degrees using Primus heaters.

Primus heaters also work well to heat groups of people working outdoors. They do have a drawback, the corrugated pipes, despite being coated in fibers, crack in the cold and break. This can be fixed by adding an elastic metal insert inside the pipe.

9. Lubrication of the tank.

SAE 40 oil was used to lubricate the tank, but experience showed that SAE 50 oil was the superior lubricant for tanks working in winter conditions. Even with an outside temperature of -60 Fahrenheit, the engine worked well and maintained a temperature of 100 Fahrenheit.

Lubricating the wheels, crankshafts, etc. was not problematic and caused no faults. There was also no need to add additional lubrication to these components.

10. Generator.

The generator insulation ended up covered in lubrication oil, but the cause was not discovered at the time.

11. Rubber tracks.

Tracks work well, even in very low temperatures. They do not crack, bulge, or wear prematurely.

12. Speedometer.

The temperature of the fighting compartment dropped so much that the oil in the speedometer became viscous and the speedometer stopped working. In order for this mechanism to work properly, it is necessary to develop and apply some kind of heating device.

13. Clutch.

When the fighting compartment was exposed to an outside temperature of less than -60 degrees, the cold air entered the tank and froze the clutch to the point that it ceased to work normally, as the disks slipped. Experience showed that when the tank stops with an exterior temperature of -50 to -60 degrees, the clutch has to be heated, otherwise the aforementioned problems are unavoidable.

At 0 Fahrenheit, the clutch worked normally,

14. Marches.

At the Western base (Little America), one tank made a 30 mile march at a temperature of -60 Fahrenheit. The tank moved in second gear, dragging a sled with a 2 ton weight. The tank could not move at a higher gear, as it was impossible to control the sled at higher speeds. The tank worked flawlessly at higher speeds without a sled, except for the driver's window being covered with snow.

The following lubricants and fuel were used for aircraft, which the expedition also had:
  • Gasoline: 87 SGR (Army, about 92)
  • Lubricating oil: Navy 1080, winter. Same as Veedal Aero-Special Heavy. "77" under Army specifications.
  • Kerosene: regular commercial.
  • Grease: Royal Special AAA for temperatures of -50 F.
Experience gathered by the Americans in their Antarctic expeditions is of some interest to us, and can be used when using American or Canadian tanks (Canadian MIIIA, American M3) in our harsh winter conditions. 

It is especially important to consider the practice of carefully pouring gasoline into M3 tanks to avoid problems with the carburettor.

It is possible that we will see the same problems with oil and air filters when using these tanks. In order to avoid breakdowns, disconnect them from the engine during the winter campaign."

Sunday 22 March 2015

World of Tanks History Section: Rematch at Uman

In the history of the Great Patriotic War, the small Ukrainian town of Uman is usually associated with the tragic summer of 1941, when 20 Soviet divisions were encircled. Its name re-appeared in reports nearly three years later, but now the Germans were wearily marching Westward through the snowy plains, and in greatly reduced numbers. A large portion remained in the clutches of the pocket at Korsun-Shevchenkovskiy, surrounded by the 1st and 2nd Ukrainian Fronts in January of 1944.

No Rest for the Wicked

Erich von Manstein himself attempted to penetrate the pocket, but neither his experience nor the extra divisions or even heavy tank battalions were enough. Only a small portion of those encircled broke out, and at a heavy cost. German tank units were in very poor condition.

The Wehrmacht hoped that the spring mud will give them a chance to restore their battered forces. At the end of February, the snow was already melting, and the roads were impassable for anything without tracks or feet.

Soviet commanders understood what the Germans wanted, and weren't about to let them rest. The next offensive, titled Uman-Botoshani Offensive, was scheduled for early March. Heavy fighting at Korsun petered out only at the end of January, giving Marshall Konev only a month to prepare.

Formally, Konev's 2nd Ukrainian Front included three tank armies, half of what was formed in 1944. In reality, he only had 670 working vehicles, the equivalent of only one tank army.

Bogdanov and Rotmistrov's armies were supposed to take the lead. Kravchenko's army remained in the second echelon. Bogdanov's experience told him that attacking with 200 tanks into several entrenched infantry divisions backed by several tank divisions is a fruitless endeavour, but the Germans were not what they used to be in March of 1944.

Trophies

The offensive began on March 5th. On the first day, Bogdanov's 2nd Tank Army broke through the German lines and reached the Gorniy Tikich river, the first serious water hazard in their path. Motorized infantry crossed it swiftly, establishing a foothold on the other side, allowing bridges for tanks to be constructed. Rotmistrov's 5th Guards Tank Army was also advancing successfully, with reasonable losses.

Things got harder the next day, partially due to German tank counterattacks. Losses increased, and a significant amount of tanks broke down due to difficult terrain. The most difficult battles of March 6th were fought by tankers and the limited number of motorized infantry that was riding on their tanks or managed to keep up on foot. Communications officers also walked, to areas where there were not enough radios and where communication airplanes did not reach. Meteorologists had little to say about the weather: "Road conditions have further deteriorated."

Elements of four German tank divisions assembled around Mankovka and Potash. After Manstein's "knocks" at the Korsun pocket, each consisted of only a handful of vehicles, but were reinforced with fresh tanks from Germany at the end of February. They could be a nasty surprise for attacking Soviet forces. Thankfully, the most combat capable units were sent to another section of the front, and Konev's armies were faced with rear line and repair units, with a generous amount of damaged tanks awaiting repairs or shipment to Germany. Counterattacks by a few hurriedly repaired tanks and SPGs had no chance against the Soviet tank armies.

After a half-hour long battle, Potash was taken from the Germans on March 7th, along with a large amount of tanks. Mankovka was lost soon after. Reports of the 2nd Tank Army read: "The enemy lost up to 500 tanks, up to 10,000 cars, and 37 warehouses with various goods near Mankovka and Potash station."

Seek and Destroy

Heavy losses and a collapse of the first line of defense meant that the Germans had nothing to stop the Soviet armoured steamroller. They had to retreat (or if you call things like they are, flee) across the accursed mud, racing Soviet tanks.

Meanwhile, tank armies turned to scavenging due to outrunning their supply lines. All food and a part of the fuel was captured. Where possible, ammunition was dropped from airplanes. Units that were less lucky had to use their tanks to carry supplies. Notes read that "tanks used for these tasks carry fuel and ammunition very slowly, as it is only possible to move in first gear".

The mud favoured the Germans, slowing down the Soviet offensive. Rotmistrov's army lost contact with the rear. Poor weather kept aircraft grounded, and HQ had to control the army through a single radio and officers on foot.

Nevertheless, the tanks pressed on. German columns sank in mud and turned the road from Potash to Uman into a scrapyard. Bogdanov's tankers reached Uman on March 8th, 1944, and began the encirclement. By next evening, the battles between Soviet tanks and German AA guns raged in the middle of the city. At the same time, Rotmistrov's T-34s "overtook and crushed retreating columns with their tracks", reaching the outskirts of Uman. On March 10th, the city was completely cleared.

The first stage of the operation was complete, but it lasted until April 17th. By the end of the Uman-Botoshani Offensive, the Red Army liberated a portion of Moldavia and Western Ukraine, and entered Romania.

Article authors: Andrei Ulanov and Aleksandr Tomzov.

Original article available here.

Saturday 21 March 2015

Oskin's Award Order

Few tank enthusiasts have not of read Oskin's feat at Ogledow, but equally few have actually read the official award order. Here it is.

"#18491
  1. Name: Oskin, Aleksandr Petrovich
  2. Rank: Guards Junior Lieutenant
  3. Position and unit: Tank commander in the 3rd Tank Battalion of the 53rd Guards Tank Fastov Order of the Red Banner, Order of Bogdan Khmelnitskiy Brigade
  4. Year of birth: 1920
  5. Nationality: Russian
  6. Party affiliation: VKP(b) candidate since 1944
  7. Participation in the Civil War or subsequent combat in defense of the USSR or the patriotic war: South Front from 1942 to February 1943, 1st Ukrainian Front since June 1944.
  8. Wounds or concussions: none.
  9. In RKKA since: 1940.
  10. Commissioned at: Korovinsk recruiting office, Ryazan oblast.
  11. Prior awards: none.
Brief and specific description of heroism: As a T-34 tank commander in a tank group, Guards Junior Lieutenant Oskin showed himself a quick and fearless officer. On August 12th, 1944, when deflecting an attack by superior forces composed of 15 Tiger B tanks (King Tiger), Oskin decided that he would rather die than let the enemy through to Staszow. Comrade Oskin entered into an uneven battle with German tanks. Calmly and surely, he opened fire and ignited three enemy tanks. The others routed under comrade Oskin's deadly fire and fell back. Comrade Oskin's machineguns also cut down submachinegunners riding on the tanks. The enemy did not reach Staszow.

On that same day, fulfilling his orders to knock the enemy out of Ogledow, comrade Oskin's tank burst into the village. With its tracks, it crushed up to 80 fascists, continuing to fire from its gun and machineguns to destroy fleeing Germans and their vehicles. In the battle for Ogledow, three Tiger B vehicles were captured completely undamaged.

For destroying 3 Tiger B tanks, a rushing maneuver to capture Ogledow leading to the capture of three intact Tiger B tanks, and bravery and heroism shown in battle while holding the foothold on the Western shore of the Vistula river, comrade Oskin is worth of the title of Hero of the Soviet Union."

CAMD RF 33-793756-35

Friday 20 March 2015

Experimental Tanks, 1933


"Report on projects of the Special Purpose Design Bureau, July 1933
  • T-39 heavy tank project. Project work 100% complete.
  • SU-14 project with B-4 gun. Project work 100% complete, working blueprints 70% complete.
  • T-26 ammunition crate project. Project work 60% complete.
  • T-26 fuel cistern. Project work 50% complete.
  • T-26 smoke tanks. Project work 100% complete, working blueprints 100% complete, sent to production.
  • T-34-1, installation of a 45 mm tank gun on the T-34. Project work 100% complete.
Design bureau chief Ivanov"

Here is a drawing of one of the T-39 designs.


As for the T-34, this isn't the WWII era T-34. It was a light maneuver tank armed with a 20 mm cannon.


Wednesday 18 March 2015

World of Tanks History Section: Labourers of Small Wars

The dust of the First World War settled. After many millions of lives were lost, the world hoped that it was the last war. Politicians and the press wrote of it endlessly. Reality, however, was much darker. Instead of one large war, the 1920s and 1930s saw many small wars all over the world where newest technology kept killing: Afghanistan, Morocco, Syria, Iraq.

Difficult Science of Small Wars

In a small colonial war, the enemy refused to follow the rules, opting out of open battle. Those that fought against European type armies knew that numerical superiority would not help, and bravery alone could not overcome modern weapons. The Europeans had to seek out their enemy in mountains and deserts. Colonists risked ending up far from their main forces, surrounded by enemies who were armed not with pikes and daggers, but modern rifles.

The situation was made more difficult due to a lack of training. Surviving veterans of WWI retired, and new recruits could barely shoot. Overall, training was lacking. In the Middle East, Soviet forces were often ambushed, as were British forces in India and Afghanistan. In Morocco, Spanish hubris led to a defeat of their 12,000 man army.

Use of armoured vehicles was a logical choice: armoured cars, tankettes, and even tanks, the world war left a plentiful inheritance. However, dozen-ton monsters that could crush fortifications could not reach the battlefield in these wars. No bridges would hold them, there would not be enough fuel, the lifespan of tracks would not last.

Benefits of Light Vehicles

Light tanks were used in these small wars. In Damascus, tanks successfully suppressed an uprising. In Afghanistan, even one light tank was enough to control a mountain pass. Two or three vehicles could complete any task: scout, attack, protect the flanks, cover a retreat.

However, tanks, trucks, and tractors needed more and more ammunition and fuel. Afghan and Moroccan tribes relied on a popular tactic: raids and ambushes. Even aircraft could not always find them: in Afghanistan and Tajikistan they hid underneath overhanging cliffs, or in the sands near wells in the deserts of the Middle East.

Tanks could not protect every kilometer of every road. The British had to rely on a complex system of small guard posts and mechanized patrols. It turned out that machineguns on armoured cars and tanks could not always elevate far enough to shoot up a mountain. At night, tanks had to close in to form a perimeter, with openings in between plugged with rocks.

Tanks of the Colonial Front

Even tanks could not compensate for problems with planning or tactics. For instance, Spain bought a dozen Renault tanks and six Schneider tanks when they discovered they could not deal with Moroccan mountain men. However, the first tank battle on March 18th, 1922 ended poorly. Tanks were supposed to cover the attack, but fell behind infantry on rough terrain. Moroccans were not afraid of the new weapons and quickly found dead zones for their armament. The Moroccans even attacked the tanks with knives; at least one driver was wounded in the face. To make matters worse, machineguns were only installed in the tanks the day before. The untested weapons began jamming when ammunition deformed from the heat.

Tank crews had to abandon three immobilized and disarmed vehicles. The tanks could not be recovered, as they were blown up with dynamite by Moroccans. The mountain dwellers set up ambushes to hunt lone tanks, sticking a metal rod into their tracks, and then pouring gasoline on the immobilized vehicle and setting it on fire. This tactic worked if there were no other tanks nearby to kill the attackers with canister shot or machineguns.

Spanish tanks redeemed themselves in an amphibious landing in September of 1925, effectively a little Normandy. Tanks that came ashore forced the mountain tribes to retreat and even leave some heights without battle. Sometimes, the tanks even succeeded without an infantry escort.  Aside from fighting in battle, the tanks pulled out trucks that were stuck, towed 75 mm guns, carried 600 kg carts with supplies, evacuated the wounded.

Tankettes, the tanks' "little brothers", also did not weather tactical mishaps well. In the fall of 1931, a Soviet unit (150 men on trucks and a platoon of T-27 tankettes) suddenly came across 600 Basmach bandits, reinforced with infantry and anti-tank trenches. The tactics manual dictated simultaneous use of all tankettes, with infantry moving up under their fire, but only one tankette was moved out. It got stuck in a hole, was shot up point blank, and burned up. The crew and unit commander died.

Small wars, despite the tiny amount of vehicles used, taught many important lessons. The most important lesson was this: never underestimate your enemy, even if he looks weak and primitive. Always remember weak and strong sides of your technology.

Original article available here.

Tuesday 17 March 2015

Sneaky SU

The element of surprise is a valuable thing in combat, but difficult to achieve when you're fighting in giant steel vehicles with roaring engines and clanging tracks. In order to sneak up on someone in a tank, you need to have real skill as a driver.

"Award Order
  1. Name: Pakhomov, Dmitriy Fedorovich
  2. Rank: Guards Sergeant
  3. Position and Unit: Mechanic-Driver in the 393th Guards SPG Demyansk Regiment
    Is nominated for the title of Hero of the Soviet Union
  4. Year of birt: 1920
  5. Nationality: Russian
  6. Party affiliation: none
  7. Action in the Civil War and subsequent conflicts in defense of the USSR: Patriotic War since June of 1943, 1st and 2nd Ukrainian Front, 1st Belorussian Front
  8. Wounds or concussions in the Patriotic War: none
  9. In the Red Army since: October 1942
  10. Recruited by: Sairam recruitment office, Yuzhnokazahstansk oblast.
Brief and specific description of personal heroism and achievements: On January 17th, 1945, during fighting for Sochaczew, he demonstrated bravery and heroism. Rushing in first out of the advance guard, he drove his vehicle at an enemy train, and, with support from tanks, destroyed it.

At night, another enemy train travelled by that railroad. Comrade Pakhomov, despite the poor visibility and swampy terrain, maneuvered and stealthily approached the train, which allowed the crew to destroy it. In offensive battle, comrade Pakhomov's tank frequently wedged itself into retreating enemy columns and caused panic.

Comrade Pakhomov's crew destroyed the following during offensive battles:
  • Locomotives with military trains: 2
  • Cars: 19
  • Carts: 29
  • Motorcycles: 2
  • Enemy soldiers and officers: up to 150
Comrade Pakhomov participated in 51 attacks, and drove his vehicle in battle for over 1500 kilometers.

For personal achievements in defense of the Socialist Motherland and numerous heroic acts, he is worthy of the title of Hero of the Soviet Union.

393th Guards SPG Demyansk Regiment commander, Guards Lieutenant-Colonel Merkulov"

CAMD RF 33-793756-36

It is not said which SU Pakhomov drove in these battles, but another award order for the same unit in January of 1945 reveals that it was equipped with SU-85s.

Monday 16 March 2015

Tank Reliability in the Korean War

In a previous article, I took a look at how many vehicles managed to reach the battlefield, and how many broke on the way there. Let's take a look at similar figures from several other sources. "The Employment of Armor in Korea, Volume I" by ORO contains information on the reliability of T-34-85 and SU-76, based on knocked out enemy vehicles.

First, T-34-85s.

Only 2% tanks lost to mechanical failure! Even assuming that no tanks were abandoned due to cowardice, a lack of fuel, or some other other such cause, that is only 27.5% of all losses. An improvement over T-34 tanks in 1942, especially considering that the conditions these tanks operated in could, at best, be described as suboptimal.




In short, no spare parts, no tools, and maintenance instructions out of the window, certainly harsher conditions than Soviet tanks faced.

Now, SU-76es.

Even better, no vehicles lost to breakdowns and 22% abandonment. Sadly, I have no Soviet SU-76 or even T-70 figures to compare them to.

Not so bad, right? Let's see what the Americans achieved under the same conditions.



These are some pretty sad figures, over 70% lost due to non-enemy action. Much higher than Soviet tanks in the same theater, and the Americans had the advantage of training and engineering vehicles present.

Sunday 15 March 2015

Overpowered AT

An interrogation of a Soviet artillery sergeant contains an interesting revelation:


"A sergeant from the 1st Battalion, 874th Anti-tank Artillery Regiment, captured on October 2nd north of Makowja was interrogated.

The regiment consists of 5 batteries, specifically 85 mm AA guns, which were converted in July of 1941. The crews were taken from several anti-aircraft regiments. He could not say why Flak guns were used in an anti-tank role. When asked if he thought that his 45 mm gun was not enough for heavy German tanks, he said that all German tanks could be penetrated by the 45 mm gun."

The sergeant was correct: 45 mm guns only had trouble with the newest German tanks that had 50 mm of front armour, and even then could penetrate them with several shots or at close range. An entire year will pass before the use of 85 mm guns in an AT role becomes necessary.

Saturday 14 March 2015

World of Tanks History Section: Gorlitskiy's "Waffentrager"

Lev Izraelevich Gorlitskiy started the war in the role of the chief designer of artillery at factory #185 in Leningrad. From June to October of 1941, his department was tasked with placing weapons into long-term fortified positions to protect approaches to Leningrad. In October, the factory was evacuated to Sverdlovsk and became a part of the Ural heavy machinebuilding factory.

One year later, in October of 1942, Gorlitskiy headed a newly formed design bureau at Uralmash, tasked with developing SPGs. A very sharp need in them was felt after new Tiger tanks appeared on the battlefield.

Deadly Classic

Three SPGs developed by Lev Izraelevich in 1942-1944 contributed significantly to victory over Germany.

Gorlitskiy's first creation was the SU-122, an assault gun. A 122 mm howitzer was placed in an immobile casemate. The gun shot HE, later HEAT ammunition. Despite numerous drawbacks, the vehicle was received well. The gun was effective against soft targets and personnel, but the low muzzle velocity did not allow it to effectively engage tanks.

SU-85 (1943) was a specialized SPG, designed to fight German Tigers and Panthers. its 85 mm gun could penetrate their armour from short and medium distances, but could be ineffective at ranges over 800 meters.

In 1944, Gorlitskiy's design bureau developed a tank destroyer with a 100 mm gun: the SU-100. It was the most dangerous enemy of all German vehicles. The only tanks it had problems with at long distances were King Tigers, Jagdtigers, and Ferdinands.

The design of all of the above vehicles was classic for Soviet SPGs: a chassis of a serial tank, casemate in the front, decent frontal armour. This layout was simple and technologically sound, but had two drawbacks. One was that the front of the chassis was overloaded, which decreased reliability of the suspension. The second was that long anti-tank guns made it more likely that the gun will stick into the ground in an unlucky move.

These issues could not be resolved in the classic style, a new approach was necessary. Layouts with a rear fighting compartment were tested, but Gorlitskiy had even more novel ideas.

New Look at SPGs

Gorlitskiy wrote in his memoirs that he wanted to make a vehicle "with long term prospects, compatible with all modern requirements". Under the new system of SPGs, the vehicles would be a part of a support class. These SPGs had to be universal, with the ability to destroy enemy tanks, fortifications, and personnel equally well.

The first step of Gorlitskiy's design bureau was to carefully study domestic and foreign experience. German Waffentrager vehicles aroused their interest. These vehicles consisted of a tracked mount with a gun on top, protected only by a light shield. This was Gorlitskiy's inspiration for the SU-100P or "item-105".

The SU-100P was not like any fully armoured Soviet SPG. Gorlitskiy bet on mobility and firepower. A new chassis was designed with armour no thicker than 15 mm. It carried a D-10S gun on a rotating mount. The gun was covered by a small open cabin and had an unheard of horizontal gun traverse: 155 degrees. The vehicle could fire from direct or indirect positions.

The SU-100P chassis was made from scratch, In a rare case among Soviet designs, the engine compartment was located in the front. A new gearbox gave the tank's driver control at any speed and on a road of any complexity. For the first time in Soviet tank building, rubberized track link bearings were used, increasing the lifespan of tracks.

In 1955, after trials and improvements, the SU-100P was accepted by the Soviet Army, but only a small number was made: no more than 24 vehicles. The main reason for this was the "rocket boom" that reigned during Khrushchev's rule.

The SU-100P's chassis had better luck. It turned out to be very much in demand. Even during trials, the chassis was borrowed by two other vehicles: the SU-152G and SU-152 "Taran". Later, the chassis was lengthened to 7 road wheels and used by many vehicles. Among them are the BTR-122 tracked APC, Krug AA missile platform, and other launchers. The chassis was also used by the Akatsiya SPG, Tulpan self propelled mortar, and Giatsint-S 152 mm SPG.

Article author: Vladimir Pinayev

Original article available here.