Sunday 30 June 2013

Lend-Lease Impressions: Centaur

The review of the Cromwell/Centaur is really quite brief, and yet so very devastating.

CAMD RF 38-11355-1389

"To the People's Commisar of External Trade Comrade Mikoyan

After receiving the cyphertext from comrades Borisenko and Solovyev on receiving "General Sherman" and "Centaur" tanks, I report that:
  1. The "General Sherman" tank is the American medium M4A2 tank. We are already receiving these from America.
  2. The "Centaur" tank is a modification of the "Cromwell" tank with an obsolete Liberty 400 hp gasoline engine, removed from production in 1919. There is no reason to order tanks of this type.
I consider it reasonable to decline the proposal of Brigadier General Firebrace to order "Centaur" tanks, and accept his offer to deliver "General Sherman" M4A2 tanks instead.

Deputy Commander of the Armoured and Mechanized Forces of the Red Army, Lieutenant-General Korobkov
Member of the Military Council, Lieutenant-General of the Tank Forces Biryukov

May 6th, 1943"

Friday 28 June 2013

Missing Index: KV-6

Everyone knows the KV-1 and KV-2, and I have previously written about KVs 3 through 5, as well as KV-7. But where is the KV-6? Wikipedia will tell you that it was an experimental tank with a flamethrower in the hull. Let's see what the archives have to say about this.  According to CAMD RF 38-11355-958:

"June 1941 [Date was recorded with a pencil and has since worn off]

On the production of tanks at the Chelyabinsk Tractor Factory in 1941, the Committee of Defense has decided:
  1. The People's Commissar of Medium Machinery (comrade Malyshev), and the Chelyabinsk Tractor Factory (comrade Shor) must, starting with January 1st, 1942, produce KV-1 tanks with 90 mm of armour, according to the requirements in attachment 1, indexed KV-6.
  2. NKTM (comrade Kazakov) and the Kirov factory (comrade Zaltsmann) must restore the tank with 90 mm of armour and a 76 mm model 1940 gun (created according to Order #1288-495), and, with three sets of blueprints, send it to ChTZ.
  3. ChTZ and NKSM must send a group of engineers and technologists to the Kirov factory to establish details of production and acceptance of the KV-6 blueprints.
  4. Allow ChTZ and People's Commissar of Medium Machinery to
    1. Begin producing KV-6 tanks in 1941, as a part of their annual quota.
    2. Independently develop KV-1 and KV-6 blueprints.
    3. Install cast or stamped turrets with the same turret ring as the KV-1 and KV-2.
    4. Conduct experimental developments of tank mechanisms.
  5. Allow NKSP (comrade Nosenko), HKB (comrade Goremykin) and factory #78 (comrade Yermolayev) to produce KV-6 hulls and turrets as a part of their 1941 tank production quota.
  6. In order to create a mobilization reserve for KV-6 tanks, NKTM (comrade Kazakov) and Kirov factory (comrade Zaltsmann) must ready blueprints, instruments, equipment, and instruments for producing the KV-6.
  7. The NKB (comrade Goremykin) must, working with NKEP, within a month, deliver a proposal for equipping factory #78 with equipment for hardening armour with high frequency electrical current."
90 mm of armour, with the implication that it wil be surface hardened. Nothing about a flamethrower. Now, 'let's look at CAMD 38-1135-67:

  1. Receive, by April 1st 1941, dimensional blueprints of a flamethrower installation on the KV-1 and KV-3 at the Izhor factory, and determine where they can be installed.
  2. When developing a flamethrower, factory #174 must keep the following in mind:
    1. The flamethrower must not impact the driver's visibility to the side.
    2. The flamethrower must be equivalently armoured to the front plate (75 mm on the KV-1, 90 mm on the KV-3).
    3. The driver will control the flamethrower. Due to this, the controls must be simple and easy.
    4. The magazine must be horizontal, and removable.
    5. The dimensions of the flamethrower, and its location, must match the attached sketch."
Sketch of a flamethrower on the KV-1. CAMD RF 38-11355-67

Blueprints of a flamethrower on the KV-3. CAMD RF 38-11355-344

Flamethrowers for the KV-1 and KV-3...but where is the KV-6? It's possible that it was renamed sometimes later, but CAMD RF 38-11355-36 dashes those hopes. The document, a list of shipments to the Leningrad front, from September of 1941, lists "KV-1 with a flamethrower mounted and the V-2K engine, #5156, #5157, #5158, plus one flamethrower mount for repairs." Again, not a KV-6, despite the KV-6 index having been established in June.

Wednesday 26 June 2013

Lend Lease Impressions: Pershing

In 1942, the Americans received Soviet KV and T-34 tanks, which inspired the design of several American tanks. In 1945, they sent a Pershing to the Soviets, to see what they thought. From CAMD RF 38-11355-2725:

"Conclusions on testing the American heavy tank T26E3

The T26E3 is an experimental heavy (by American standards) tank, whose main combat qualities surpass those of other American tanks. However, the T26E3 does not satisfy modern requirements for a heavy tank. The main disadvantage of the T26E3 is its weak armour. Other tank weaknesses include:

1. The engine radiator, transmission lubricant radiator, differential lubricant radiator and 4 fans are in one unit, making repair of any one of these devices difficult.
2. There are many open spaces in the transmission and engine compartments. These spaces are not used for anything, nor are they necessary for maintenance.
3. The inner and outer road wheels are not loaded equally. As a result, the rubber tires on the inner road wheels wear much faster.
4. Insufficient ventilation of the fighting compartment leads to unacceptably high concentrations of CO in the fighting compartment when the gun is fired.

The T26E3 was tested on the NIBT proving grounds from May to July of this year. In total, the tank traveled 493 km. 150 km were used for training of the crew. The road condition was a dirt road, destroyed by tanks, in places covered with mud. The relatively small amount of driving on only one kind of road did not provide enough data on the reliability and performance of the tank on different terrain types.

The average speed of the tank on a dirt road is 18.9 kph, which is good for a tank that weighs 39.4 tons. This speed is achieved by:
a) a hydromechanical transmission
b) a suspension that provides very smooth travel, achieved by hydraulic shock absorbers on the road wheels.

A hydromechanical transmission also improves the ease of handling, accelerates the tank quickly, and provides good engine performance. The engine performs in a narrow range of RPM (2300-2500). The transmission input gear group provides the ability to start moving up a slope as steep as 30 degrees.

The engine temperature remained stable and within normal parameters during testing. The operational range on a dirt road is 100-115 km, which is sufficient. The driver's levers take between 25 and 35 kg of force to move, which is high.

The tank was tested on naturally occurring slopes up to 31 degrees. That appears to be the limit, at which the tank's tracks lose traction.

The armament testing showed:
1. The 90 mm gun M3 has the muzzle velocity of 810 m/s, which is higher than any known American tank gun.
2. Rate of fire when in place is equal to 6-7 rounds per minute.
3. Rate of fire when moving is 2-3 rounds per minute.

Aside from the hydromechanical transmission, other interesting features of the T26E3 include:

1. High visibility from the tank, provided by a commander's cupola with vision ports, and a large amount of periscopes mounted on the tank.
2. Connection of track links with silent-blocks.
3. Electric engine control devices.
4. Driver's seat construction.
5. Driver's compartment heating and ventilation devices.
6. Hydraulic shock absorbers on all road wheels other than the middle one.
7. Ammo rack placement at the bottom of the hull, and a conveniently placed ready rack.
8. Cooling fans directly powered by the engine."

Monday 24 June 2013

Soviet 45 mm AT Guns

Out of all the Soviet guns produced in the war, the "sorokopyatka" (forty-fiver) was not the biggest or strongest, but it retains a special place in history. The Soviet Union produced numerous guns that were 45 mm in caliber, and they proceeded to fight through the entire war. Each different gun was improved, and had a different name, but they were all known colloquially as "sorokopyatka".

The first such gun was the 45 mm anti-tank gun model 1932 (19-K). Using components from the license-built Rheinmetall-Borsig 37 mm gun and a new 45 mm barrel, a new anti-tank gun was born. It was installed in tanks under the name 45 mm tank gun model 1932 (20-K). Various modernizations of this gun, including a prototype to make it magazine-fed, continued until 1937.

Towards the end of 1937, model 1932 was pushed out by the 45 mm anti-tank gun model 1937 (index 53-K). The new gun had better ballistics, a higher rate of fire, and was more reliable. The new wheels were also made of metal, and not wood (model 1932 also received metallic wheels in 1937).

The tank guns also underwent modernization. The 45 mm tank gun model 1938 had some new features compared to its towed sibling, the most interesting of which was a TOS stabilized gun sight, allowing for accurate fire while the tank was in motion.

The USSR met WWII with a large number of 45 mm model 1937 guns. While they were more than enough against the front of obsolete light tanks, front armour of newer models gave them trouble. APCR shells solved that problem somewhat, but tungsten was expensive, and the gun was further modernized in 1942 into the 45 mm gun model 1942 (M-42). As well as a longer barrel, the gun received a thicker shield, in order to protect the crew from armour-piercing bullets. The USSR stopped producing the gun in 1945, but it was used in Finland as an AT gun until 1966, and only completely removed from service in 1986.

The 45 mm gun had a number of shells developed for it. The high explosive shell generated 100 fragments, with a radius of effect of 10 meters. The penetration capabilities of the AP-tracer shell will be explored further in the article. There was also an AP-tracer-incendiary shell, which ignited gasoline with 100% chance, kerosene with 80% chance, and diesel with 60% chance. Lastly, there was a grape-shot round that spread 150 bullets in a 9 degree cone.

Now, for some tests! Let's dust off the good old  "Report on the shooting of German tanks with AP and HE shells from tank guns" (CAMD RF 38-11355-832). I will also throw in tactical diagrams developed by NII-48 in their report: "Topic 2VV-2, Investigation of the armour of tanks of the German army" (CAMD RF 38-11355-778). The report contains the following data for shooting at the armour plates at various angles, which was used to make the tactical diagrams.

  • 30 mm: 
    • 0 degrees: 20% chance at 1600 meters, 80% chance at 1400 meters.
    • 25 degrees: 20% chance at 1100 meters, 80% chance at 1000 meters.
    • 35 degrees: 20% chance at 1000 meters, 80% chance at 900 meters.
    • 45 degrees: 20% chance at 500 meters, 80% chance at 250 meters.
    • 55 degrees and above: 20% chance at 50 meters.
  • 40 mm
    • 30 degrees: 20% chance at 600 meters, 80% chance at 50 meters.
  • 20+20 mm
    • 0 degrees: 20% chance at 650 meters, 80% chance at 150 meters.

First, we have the Pz 38(t), facing off against a 45 mm gun model 1934 (slightly modernized model 1932).

100 meters, a shot to the 50 mm front. The shell penetrates. Entrance diameter: 49 mm. Exit diameter: 55 mm.
200 meters. One shot penetrates. One shot does not, leaving a 20 mm deep dent in the second armour plate. A third shot penetrates again.
400 meters. The first armour plate is penetrated, but not the second.
800 meters. Insignificant damage to the first armour plate. Aiming a bit higher, at the turret armour underneath the gun, the shell penetrates. The turret ring is destroyed.
At 1000 meters, the gun penetrates the side of the turret. At 800 meters, it penetrates again, making a hole 80 mm wide at the entrance, 100 mm wide at the exit, as well as three 300 mm long cracks, and a dent on the other side of the turret, with spalling on the other side.
Another shot from 800 meters ricochets. The next makes a hole in the side of the hull. Entrance diameter: 100 mm. Exit diameter: 150 mm.
A parting shot from 1000 meters penetrates the right side of the hull.

Conclusions: "The 45 mm AP-T shell penetrates the front armour, 50 mm thick, from 200 meters. Side armour, 30 mm thick, can be penetrated by the AP-T shell from 1000 meters."

The NII-48 report calculates more precise figures for the distances. The side of the turret platform can be penetrated at 1070 meters. The side of the turret can be penetrated at 970 meters.

Tactical diagram of a Pz 38(t). The 45 mm gun is shown on the left side.

The next victim of the 45 mm gun is the StuG. The gun is now a model 1942.

Two shots at the front, from 50 meters and 100 meters. Both fail to penetrate, making 20 millimeter dents. The side of the hull is penetrated twice from 850 meters.

Conclusion: "The 45 mm AP shell fired from a model 1942 AT gun cannot penetrate the front armour at any distance. The side armour, 30 mm thick, can be penetrated from 850 meters."

By NII-48's calculations indicate that a 45 mm gun can penetrate the side of a StuG from 1070 meters, and rear at 750 meters.

Tactical diagram of a StuG III. The 45 mm gun is shown on the left side.

Next up is the model 1934 again, against a PzIII. Two shots from 50 meters tear off the first 30 mm screen from the front of the tank.
The next shot hits the right turret hatch, from the right. The shell penetrates the turret, tearing off the hatch, and making a 200 mm crack in the turret. A shot at the rear of the turret from 800 meters penetrates. A shot from 900 meters at the front of the turret penetrates, and jams the turret. Shooting at another hatch from 900 meters tears off 6 bolts, 4 of which fly inside the tank. Two shots at the right side of the hull from 900 meters make penetrations (one as big as 75 mm entrance and 120 mm exit), and make a crack in the turret platform. A ricochet from 900 meters makes a 200 mm crack in the right turret side. Another shot to the right side results in a penetration, as well as an 80 mm crack. A parting shot to the right results in a penetration with an 80 mm exit diameter and spalling.

Conclusions: "The 45 mm shell does not penetrate 60 mm of front armour at any distance. It can penetrate the 30 mm turret armour from 800 meters. The side armour, 30 mm thick, can be penetrated from 900-1000 meters."

NII-48 calculations: The lower front plate can be penetrated at 200 meters. The side can be penetrated at 1070 meters. The side of the turret can be penetrated at 640 meters. The rear of the turret can be penetrated at 860 meters.

Tactical diagram of a PzIII. The 45 mm gun is shown on the left side.

Pretty good result, persistent hits to the front result in the tank being knocked out at up to 800 meters! Better than NII-48's calculations, since the shells can penetrate armour that was theoretically impenetrable. Let's take a look at what can be done against a PzIV with the same model 1934 gun.

At 50 meters, the armour is penetrated. At 100 meters, three shots only make dents, and result in cracks on the rear side.
40 mm side armour is penetrated from 400 meters. The next shot "cut a 200 mm long path through the 20 mm horizontal plate of the turret platform, and penetrated the right side of the turret".
At 600 meters, the 45 mm gun can only penetrate the first 20 mm armour screen, but not the second. However, after 5 shots, the screen falls off, as well as an idler. From 800 meters, the results are the same: penetration of the first screen only. HE from 200 meters is ineffective.

Conclusions: "The 45 mm AP shell, when fired from a model 1934 AT gun, penetrates the 50 mm thick front armour at 50 meters. Side armour is penetrated at 400 meters. Un-screened sides of the engine compartment, rear, and turret, can be penetrated at any effective combat distance."

NII-48's calculations are a bit pessimistic: "The front parts of the tank cannot be penetrated by 45 mm shells." The distance given for the screened sides is 310 meters, side of the turret platform is penetrable from 1070 meters, rear of the hull from 940 meters. The calculations agree: non-screened portions of the tank can be penetrated at any distance and angle.

Tactical diagram of a PzIV. The 45 mm gun is shown on the left side.

"Investigation of the armour of tanks of the German army" also has test data for tanks not in the previous report.

The Pz II Ausf B hull can be penetrated in the front from 580 meters, or 680 meters when shooting at the turret or turret platform. The rear can be penetrated from 1070 meters. Other parts can be penetrated from any distance.

Tactical diagram of a PzII Ausf B. The 45 mm gun is shown as a continuous line.

Surprisingly, the 45 mm gun was also tested...against the T-34.

Tactical diagram of a T-34.

This diagram shows "possible penetration" (20% chance). Even then, the 45 mm gun can penetrate the overtrack hull at 100 meters, and side from 300 meters. This is a much better result than any of the tanks listed above.

Sunday 23 June 2013

World of Tanks History Section: Maus

Many achievements of the German tank-building school command respect. Engineering solutions used in German tanks during WWII were used on tanks for years after. One must only remember the German obsession with superheavy tanks to realize why Teutonic genius earned its "gloomy" label. It is considered that the tendency was caused by Hitler. However, the first such tank started development years before he rose to power, at the end of the First World War: the "Colossal", a 150 ton monster with 4 guns and a crew of 22. The end of the war and Germany's defeat prevented its completion. It would be more correct to say that Hitler turned a casual hobby into an insane obsession.

To be fair, Germany was not the only country that built tanks like these. The USSR was planning a 120 ton KV-5, the Americans built three massive T95s, the Japanese built a model of a 100-ton three-turret O-I tank. The French also had their FCM 2C. All of these were independent projects, but in the Third Reich, it was a general trend.

Some say that the Germans started making inherently useless tanks out of desperation. This is incorrect. Work on super-heavy tanks started in 1941. Krupp was developing a 72 ton tank, with a 105 mm gun. Then, the company also came up with the 90-ton Lowe, which was cancelled after Porsche received the contract for the Maus tank.

There is no ignoring of two other projects, which cannot be called anything other than curious. The mind behind the first was the German engineer E. Grotte, who worked for the USSR in the early 1930s, and already shocked the military with his land cruisers. Grotte then proposed a 1000 ton Ratte to the Germans. This hellish creation was to be armed with naval guns. The next project, surpassing even the Ratte, was created by Krupp. Its gun was the 800 mm Dora gun. Minister of Armament Speer managed to save some common sense, and nip the "genius breakthroughs" in the bud.

The only superheavy tank German completed was Professor Porsche's Maus. The contract for it was signed in 1942. Porsche was to build a 160 ton tank with two guns (150 mm and 105 mm), with 200 mm of front armour, and 180 mm of side armour. The project was named "Mammoth". In December of 1942, for secrecy, the project was named "Mauschen". Ferdinand Porsche was tasked only with the technical side of the project. Speer was supposed to implement it into production.

Porsche did not meet the weight requirement. The desire to create a vehicle protected from all sides and problems with the layout resulted in a tank that weighed 188 tons. No permanent bridge would be able to carry this weight, let alone pontoon bridges. Its designers created the Maus with the intention of making it waterproof and equipped it with a system for driving underwater. Theoretically, the tank could cross rivers up to 8 meters deep. Realistically, even a small body of water would have become its grave.

The off-road performance of the Maus was inadequate. Reports on trials at Boblingen were exceedingly optimistic. For instance, they say that the tank maintains the ability to move after being submerged in the ground as much as 50 cm. What the report doesn't say is that nearly all of the 100 km of trials were done on paved roads and hard soil. The only instance of off-road testing resulted in the Maus sinking nearly to its roof. The tank could only be retrieved after being dug out. What good would the aforementioned underwater driving apparatus be if the tank would get stuck in the silt?

There exists an axiom that a tank must be mobile. The point of tank units is that they can make long marches quickly, and strike at the enemy flanks and rear in an offense or defense. The Maus did not satisfy this requirement. It drove very poorly.

One might ask: "was the Maus protected enough to make up for its immobility with armour?" Again, the answer is no.

First, the thick armour of the Maus was of very poor quality. When it was built, molybdenum, crucial for quality steel, was in harsh deficit in Germany. Poor armour was not only easily penetrable by shells, but also cracked and spalled. A hit on the vehicle knocked out fragments on the other side, which killed crew members and destroyed components. Practically, the Maus was as protected as a 60-70 ton tank.

Second, the massive size of the Maus made it an excellent target from the air. The Maus could not have survived a hit from a bomb. Its effectiveness is highly questionable.

The only good thing about the Maus was its 128 mm gun. The gun was guaranteed to penetrate any enemy tank at 2500 meters. No Allied tank could claim such a feat. Unfortunately, the gun had two-piece ammunition, and loading speed was limited to 3 rounds per minute. Nevertheless, the 128 mm gun was a plus. The second 75 mm gun was more questionable. In order to take out guns not worthy of the main gun, an autocannon would have been enough. It would also be preferable if the gun had a 360 degree range. The Maus turret turned exceptionally slowly, and the rear machine gun was insufficient for defense.

It can be asserted with a near 100% certainty that any Maus, if sent into battle, would be lost irreparably. The evacuation of such a massive tank would be an impossible task. Isn't it a little wasteful to abandon such expensive vehicles?

Sadly (or maybe happily), the Germans never had a chance to find out how well the Maus fought. Two prototypes were destroyed at Kummersdorf when the Soviets approached. [Note: this statement is not entirely accurate. While both Maus prototypes were sent to Kummersdorf for testing, one met its end at Stammlager.] The Soviets put together one working tank out of two, and sent it back. It is currently on display at the Kubinka museum.

In conclusion, Ferdinand Porche, following Hitler's gigantomania, created the most useless tank of WWII. Was all effort aimed at the Maus futile? Not entirely. Many innovative solutions were applied in the tank's construction, in the field of suspensions, engines, electrics, cooling, fuel delivery, and turret construction.

Original article available here.

Friday 21 June 2013

IS: 1 vs 12

IS tanks didn't have the same invincibility as the KV enjoyed in 1941, but their armour was still formidable against German guns.

CAMD RF 3153-1-6

The handwritten text reads "This IS tank has 16 dents from enemy artillery shells. The commander of the tank, Guards Junior Lieutenant Neelov, destroyed 3 enemy tanks, 2 enemy SPGs, and 7 enemy guns."

The printed text reads "In the aforementioned battles, our IS tanks played an active role. Brave tankers fearlessly fought enemy tanks, and destroyed enemy positions with guns and tracks."

Wednesday 19 June 2013

Critique of American Tanks

"American tanks (M3 medium and M3 light) are impossible to use in an offensive against a dug-in enemy. Their insufficient armour, large size, and poor maneuverability (cannot rotate in place, difficult to rotate at low speeds), high chance of catching fire due to easily ignited fuel, all lead to losses of tanks and insufficient results. It is also impossible to use American tanks in mud, or in winter, as the high ground pressure leads to poor track performance.

Other weaknesses include: poor location of the engine in the hull, which leads to inconvenience during removal and repair, poor gearbox and differential construction, joined in one unit (M3 light) or located inside the tank hull (M3 medium), poor reliability and frequent breakdowns of Browning machineguns, lack of HE shells for the 37 mm gun (M3 light and M3 medium).

American tanks can be used in:
  • An echelon during a breakthrough, accompanies by KV and T-34 tanks.
  • In pursuing a retreating enemy, and fighting his mobile defenses.
  • A sudden attack on a weakly fortified enemy.
  • During a defense, from ambushes.
Deputy commander of Armoured and Mechanized Affairs of the 61st Army, Colonel Shirobokov, September 13th, 1942."

From the same officer, "Report on combat use of American tanks (M3 medium and M3 light)".

"...The tanks easily catch fire when shot. For example, during the operation on July 5th, 1942:
  • Out of 31 M3 lights, 24 burned.
  • Out of 14 M3 mediums, 14 burned.
During the operation on August 14th:
  • Out of 30 M3 lights, 22 burned.
  • Out of 14 M3 mediums, 12 burned."

Monday 17 June 2013

Ramming Speed!

Tank ramming is occasionally mentioned in discussions of tank combat. Several times, I have seen the claim that tanks, due to the inability to penetrate the armour of the enemy, resorted to ramming them en masse. That assertion is, of course, laughable.

Tank rams, despite the beliefs of some, were not a very common occurrence. They happened in exceptional cases, where the gun was damaged or out of ammunition, or the two tanks found themselves unexpectedly close. Various sources count 52-160 tank-on-tank ram maneuvers being performed during all of WWII, in total. Let's take a look at some recorded ramming maneuvers, in roughly chronological order.

The first recorded tank ram happened before WWII, during the Spanish Civil War. As is well known, the USSR was supplying T-26 tanks and volunteers to the Republican army. One of these volunteers, Lieutenant Osadchiy, used his T-26 tank to shove an Ansaldo tankette into a valley. 

The first tank ram of WWII happened on the day of the attack on the Soviet Union. Lieutenant Gudzya's KV-1 tank rammed several German PzIIIs and an APC. 

Another KV-1 ram is described by Lieutenant-General Popel in his memoirs. "In the heat of battle, the KV commanded by deputy political chief Zhegan went for a ram. The fascist tank was destroyed. From the impact, the engine of the KV stalled, and Zhegan and his driver, Ustinov, lost consciousness. Only the gunner, Mihailov, continued fire while he had shells. The Germans spotted a Russian tank, alone on their flank. Infantry crawled up, climbed up on the tank, started kicking the turret. Zhegan was awakened by this noise. Ustinov was already fiddling with the engine, but could not get it started. The Germans decided to tow the KV with the crew still in it. A PzIV pulled up, and the crew hooked tow cables on the KV. The tank did not move. Another try. The KV started moving. This movement allowed the engine to restart. Ustinov grabbed his levers. Who would win? Our engine was stronger, our tank was heavier. The fascists jumped out of their tank as it moved. The KV is here, right in front of us."

Interestingly enough, another similar incident occurred. Boris Polevoy, a field reporter, wrote: "The KV stalled. The fascists were interested in the new vehicle. They decided to tow the tank away. Two tanks were attached to it with steel cables. The driver, Grigoryev, was ready. He turned on the spare gas tanks and reversed. The powerful vehicle dragged the two enemy tanks. Grigoryev delivered the two tanks to his unit. For his courage, he was made a Hero of the Soviet Union."

While Zhegan's KV took quite a bit of damage from that ram, it did not always happen that way. The KV and T-34 were very heavy, well armoured, sturdy tanks, with powerful engines, making them very good at ramming. The crew commanded by Hero of the Soviet Union Bosov performed 4 tank rams during the Battle of Moscow. KV driver Tomashevich performed 3 rams in one battle on July 12th, 1941. I. Rogozin performed 3 rams at Krivoy Rog, and Lieutenant I. Butenko and Senior Lieutenant P. Zaharchenko performed two rams. 

On June 26th, 1941, Captain Arhipov rammed PzII and PzIII tanks that stopped to refuel. His tanks and crews were in good enough condition to take prisoners. Ramming was chosen in this case due to the operation being carried out at nightfall, and well-aimed gunfire being impossible.

A unique ram was performed on July 7th, 1941. The situation is described by three different sources. From the German side: "7th company of the 1st tank regiment and 2nd company of the 1st motorized regiment stopped and formed a defensive perimeter at an intersection north of Letovo. A fierce tank battle broke out. Around 17:00, the 1st platoon of the 7th company (Lieutenant Fromme) that was guarding the north side received a message about enemy tanks moving in to the crossroads. The company commander, Hauptmann von Falkenberg, saw that a Christie tank that Fromme destroyed rammed his tank (#711) at full speed. The next tank did the same. The enemy crews attempted to escape. Lieutenant Fromme climbed out of his tank and took them prisoner. However, due to reloading his pistol slowly, he had to defend himself with an ax against enemy infantry. He was forced back into his tank with light wounds. After that, more enemy tanks arrived, which tried to pass through the intersection at high speeds."

From the Soviet side: "A curious situation arose in the vicinity of village S. German tanks attacked our infantry. A platoon commanded by Junior Lieutenant Kozulenko received a mission to counterattack and break up the offensive. The only possible route to counterattack was through a bottleneck, where only one tank could pass, and it was currently occupied by a fascist tank. Kozulenko rammed it, knocked it off, and guided his platoon through the bottleneck. The fascists, stunned by this courageous push, turned around and retreated."

From Kozulenko's award order: "Comrade Kozulenko, while fighting German fascists on July 7th, 1941, in defense of the city of Pskov, in the region of Solovyi-Lopatino, where it was necessary to hold against an enemy attack. Comrade Kozulenko, with disregard for his well-being, rammed a German heavy tank with his light tank. As a result, both tanks caught fire, and the path for German tanks was blocked. Comrade Kozulenko left his tank, destroyed the enemy tank crew, and returned to his unit. - Commander of the 3rd Tank Division, Colonel Andreev."

Photograph of the aftermath at the crossroads north of Letovo.

At first, the image seems perfectly normal. However, look at the turret number of the tank seen through the bridge handrail. It is #712. Fromme's tank was #711. Looks like the German report was inaccurate. Instead of both BT tanks ramming #711, one rammed #711, and the other rammed #712. Another award order confirms this: "Comrade Saprykin, during battle in the region of Lopatino-Solovyi, fearlessly destroyed fascists and their tanks. With ramming, he destroyed several enemy tanks. After his tank was immobilized and caught fire, Saprykin, with a machine gun in hand, continued to deflect enemy assaults, killing numerous fascists."

Here is another ramming photo.

I don't have any details on this one, but you can see how devastating a charging T-34 is. The StuG's drive wheel was knocked clean off. 

KV-1 after ramming an 88 mm AA gun. Destroying guns with a tank's tracks was a fairly common occurrence. 

Most of the tank rams happened during the Battle of Kursk. 50 rams were performed by Soviet tankers, 20 at Prohorovka. Mostly, smaller and lighter tanks like PzIIIs and PzIVs were victims of rams, but even heavier German tanks were immobilized when rams destroyed their tracks or wheels. Ivan Feofanovich Kamenetskiy tells the story of one of them: "...I didn't see so many tanks in the whole war, there were less of them in Berlin, I think. Our tanks went into an attack, and we rode on them, 4-5 per tank. I held my submachinegun at the ready. German tanks came up in front of us and opened fire. We dismounted. One of our tanks rammed a German steel monster. I saw how the enemy crew bailed out, and tried to run back to their side. We shot them. It was truly scary, a real slaughter. But we managed to stop the enemy and continue our advance."

Ramming, of course, is more effective against lighter targets, and also those that cannot avoid being rammed. A grounded airplane is a perfect match. Drivers of the 24th Tank Corps rammed 300 airplanes on the ground and 50 loaded on trains right before an offensive during the Battle of Stalingrad, on December 24th, 1942, at the Tanitskaya railroad station. 

Airplanes were also rammed at the airport next to the Polish city of Lubek on January 11th, 1944, where 17 planed were destroyed, and on January 17th, 1945, when 20 planes were destroyed by ramming and cannon fire. 

Soft vehicles are also perfect as targets. Viktor Mihailovich Kryat describes how two KV tanks rammed a German convoy. "At Rzhev, I saw how well our KVs fought. Two KVs against 30 German tanks. The Germans shoot, and the KVs shrug it off. The KVs got up on the highway and started ramming and crushing cars. When we got close, they had so many dents on them. No AT guns could handle us at that time, the Germans had no such shells."

A curious incident occurred on June 24th, 1944, when the crew of Lieutenant Komarov rammed an armoured train with his T-34. A shot from a German armoured train lit his tank on fire and injured him. Komarov's driver, Buhtuyev, rammed the burning tank into the German train, and overturned two train cars. Buhtuyev died, but Komarov escaped into the nearby forests, and was rescued by partisans several days later. Komarov recovered and returned to the front. For his maneuver, he was also made a Hero of the Soviet Union. Another armoured train was rammed by Captain Leonid Maleev. He received his Hero of the Soviet Union posthumously.

Svirin, in his book "Assault Gun Sturmgeshuetz III" describes an instance of a tank ram that was closer to a car accident than an intentional combat action. Three StuH 42 vehicles ran into the advance guard of the 3rd Guards Tank army, quite literally. In the fog, both sides confused the enemy for their own, and climbed out of their tanks to resolve the issue, without bringing as much as a pistol. A StuH gunner that realized that was happening fired, but with an HE shell, killing both Soviet and German tankers. Two of the StuHs managed to escape, dealing minor damage to one of the Soviet tanks. 

Of course, not only Soviet tanks performed rams during WWII. A famous photograph shows a Sherman tank and a Tiger II together. The Sherman rammed the Tiger II, knocking out both tanks.

Sunday 16 June 2013

World of Tanks History Section: BT

The Collegiate of the Chief Directorate of Military Manufacturing met at the end of 1929. The main conclusion of these meetings was that the Soviet tank manufacturing industry is incapable of equipping the RKKA with armoured vehicles. Domestic tanks were inferior to foreign ones, newly planned tanks kept getting delayed, engineers lacked appropriate experience. Factories did not have enough materials, equipment, tools, skilled workers.

Based on these conclusions, the commission decided: if we can't do it ourselves, let's use foreign expertise, Invite engineers, buy tanks and documentation. On December 30th, a delegation was sent to America, headed by Innokentiy Halepskiy, the head of the Directorate of Mechanization and Motorization of the RKKA. The delegation's task was to familiarize themselves with samples of latest tanks and purchase them. At first, the work of the Cunningham company seemed the most interesting, but it turned out that the tanks did not match the advertised performance parameters, and are far behind the Vickers tank the USSR already purchased. Further negotiations with Cunningham ceased, and the delegation switched to convertible drive vehicles developed by Christie.

Despite the fact that Christie's tanks reached record speeds, the US army showed no interest in them, as the navy was considered the main weapon of the US. The army was in a secondary role, and had few tanks (why have tanks when the odds of an invasion is negligible?). When Halepskiy familiarized himself with Christie's tanks, he hesitated. On one hand, the tank had no place in the USSR's tank doctrine. On the other hand, the engineer, although with no love for the Communists, was willing to cooperate. He was prepared to not only share all documentation on the tank, but to accompany them to the USSR. The reason for this was simple: the commission was willing to pay a significant amount of money.

The last doubts about the purchase disappeared when the commission discovered that Poland was willing to buy the tanks. If someone were to make a list of the most dangerous enemies of the USSR at the time, Poland would have made top 3. It had a powerful army for the time, with a rapidly developing tank force.

On April 28th, 1930, a contract for two Christie tanks was signed, with accompanying documentation. These were new models were named M1940. The USSR was ready to pay 60 thousand dollars. When the tanks made it to the USSR, it turned out that they were lacking turrets and armament, and the documentation was incomplete. Christie was penalized 25 thousand dollars, and was not invited to the USSR.

The vehicles were sent to trials. In order to objectively evaluate the performance of the tanks, the turret weight had to be accounted for. As the replacement turret was still in development, it was replaced with an 800 kg weight.

Trials showed that Christie's child was poorly behaved, and prone to tantrums. An attempt to turn at high speed on grassy terrain resulted in a wheel carrier falling off. Two days were spent repairing it, but it broke off again after 500 meters. It was repaired again, and failed again. Deadlines were approaching, so it was decided to keep testing in wheel mode. Even here, the tank was not performing well. The tank had great difficulty moving on harsh terrain, and was completely helpless in sand. The driver was rapidly worn out by the inconsistent behaviour of the vehicle and the fact that the steering wheel was literally jumping out of his hands. The engine was in need of constant tuning. The battery could not always start the engine, and entirely incapable of it in cold weather. The gearbox heated up after 2-3 hours, and often broke. The front hatch was too small to fit a person, and the entire crew had to climb in through the turret ring.

Despite the vehicle's questionable qualities, the army decided to adopt it. According to existing classification, it would have been named T-28 or T-29. However, since it did not match doctrine, it was given a new index: BT (fast tank).

Mass production of the BT tank was planned on the Yaroslav automotive factory. However, it was obvious that the factory would be incapable of supporting this load. The Bolshevik factory was considered an alternative, but was also overloaded. Suddenly, the Kharkov Komintern factory was freed up when an order for 200 T-24s was cancelled. The BT order was moved there.

The poor performance of Christie's tank showed that copying it would be fruitless. The turret also had to be developed anew. The task of finishing the tank was given to N. Toskin.

In 1931, 6 BT tanks were scheduled to be produced for the November 7th parade. The factory, however, was not particularly eager to produce a new, untested tank. The pressure came from the very top, and three prototypes managed to be produced, two of which made it to the parade. The third tank suffered an engine fire. This incident cast doubt on the necessity of developing the BT tank, but production continued.

Mass production of the BT started slowly. There was a deficit in everything: raw materials, tools, skilled workers. Parts shipments were constantly late. 50 sets of ball bearings were due for January 1st, 1932. 7 sets were actually produced. 8 "Liberty" engines, 3 hulls, and 4 gearboxes were produced. There was a problem with engines, overall. The "Liberty" engine was produced in the USSR under the brand "M-5", but was already removed from production at that point. It was necessary to buy all the "Liberty" engines available in the US, even broken and used ones. These engines were hard to start, constantly overheated, and sometimes self-ignited.

At this stage, the BT achieved the fame of unprecedented breakdowns. The engines broke, the tracks, made from poorly conditioned steel at the Kramator factory broke, the gearboxes worked poorly.

Most BT tanks made it to army units with no armament, as the PS-2 gun that was intended for the tank was not accepted into service. The B-3 gun was accepted instead, a mix of the PS-2 and German 1K Rheinmetall gun. However, these guns were produced in limited numbers, and it was impossible to outfit a tank with them. As a temporary measure, the gun was replaced with dual machine guns. There was a plan to replace them with a 45 mm gun, but most BT tanks stayed with machine guns. The mass produced BT had four main armament types:

-Two machine guns in one mount.
-Two machine guns in one mount and a third one separately.
-One 37 mm cannon, no machine gun.
-One 37 mm cannon and one machine gun.

396 BT tanks were produced in 1932. In 1933, the BT was renamed BT-2, and 224 more were produced.

The army was not too happy with the new tank. It was too unreliable. The only way it could make the command staff happy was by setting records when jumping from ramps. The BT-2 was seen as a training vehicle, until superior tanks were built. BT-2 tanks were almost entirely used for educational and secondary tasks.

The tank was produced from 1932 to 1933. In 1933, the tank was replaced by its modernization, indexed BT-5.

Regardless, the tank became a new step in Soviet tank-building. It was the first to use a powerful engine, convertible drive, a candle suspension, and a powerful gun for its time. If you compare the BT-2 to foreign tanks of the era, it was one of the best, and remained competitive until the end of the 1930s.

The BT-2 first fought at Khalkin-Gol in 1939, and then during the campaign in West Belarus and Ukraine. A large amount of these tanks took part in the Winter War. In the latter conflict, the largest cause of losses was not combat. The BTs broke down, and had to be sent to the factory for repairs.

By 1941, the tank was totally obsolete. Its armour protected only from bullets, and did not pose a problem for AT rifles at close ranges. Any German tank, aside from the PzKpfw I, could penetrate the BT-2 at any distance. The BT-2 was suitable for scouting, patrols, and other support tasks, as a part of a larger tank force. However, the first years of the war offered no choice.

About 390 BT tanks fought in WWII. They were included in mechanized corps, and fought through the entire front. Most tanks were destroyed in the summer and fall of 1941. However, the tanks continued to fight on the Leningrad front until 1943. A photo exists of a machine gun BT, taken in 1942. According to some sources, BTs were still used in 1944.

No BT-2s survive to this day.

Original article available here.

Friday 14 June 2013

Soviet Very High Power Guns: BL-9

I have previously written about the BL-8 152 mm Very High Power gun, and briefly mentioned the BL-9 Very High Power gun. Here is how both of these projects started. Surprisingly enough, they were originally meant not for the ISU-152, but for the SU-152. CAMD RF 81-12063-1 tells the interesting story.

"The special NKV telegram #5014 sent on September 24th, 1943, tasked OKB-172 and the #172 Molotov factory to develop a 122 mm self propelled gun, capable of reaching 1000 m/s muzzle velocity with a 25 kg shell.
Giving the highest priority to this project, OKB-172 completed the draft ahead of schedule, and presents it for your approval. As a result of performing the draft work, we have discovered the following:
  1. The task of creating an SPG with the muzzle velocity of 1000 m/s can be accomplished by installing a new barrel on the KV-14 SPG, to replace the model 1937 howitzer, and a new single-sided hydro-pneumatic balancing mechanism. 
  2. As the power of cannons constantly grows, you may be interested in our installation of an OBM-43 barrel, with the muzzle velocity of 880 m/s and a 43.5 kg shell, on the KV-14 SPG, instead of the 122 mm barrel with the 1000 m/s muzzle velocity. Such a solution raises the power of the SPG by 33.5% and increases its armour piercing and concrete piercing capability.
With this solution, not only does the SPG receive a more powerful gun, but the gun is already in use, and will ease production and use of the guns."

KV-14 is, of course, the pre-production index of the SU-152. 

The document then provides comparisons between the different gun options: the ML-20S, 122 mm OBM-50 (BL-9) and the yet unnamed 152 mm gun. The ranges at 22 degree elevation (max elevation for all guns) are: 12 km for the ML-20S, 21 km for the BL-9, and 18 km for the new 152 mm gun. The penetration for both experimental guns at 1500 meters is 195 mm against flat armour, and 160 mm against armour angled at 30 degrees. This is pretty close to the figures given in that other penetration table (197 mm against flat and 160 mm against angled armour). All three guns have the same horizonal traverse: +/-7 degrees. They can carry 16 shells (38 for the new guns with a redesigned fighting compartment). The projected rate of fire is 1.5 RPM for the ML-20S, 2 RPM for the BL-9, and 1.33 RPM for the 152 mm gun. The mass of the SPG is 47 tons with the ML-20S, and 48 tons with either of the new guns.

However, the OBM series wasn't only destined for tank destroyers. A 122 mm OBM-51 gun, almost equivalent to the OBM-50 (BL-9), was planned for a heavy tank. The project requirements were:
  • 1000 m/s muzzle velocity
  • 200 mm of penetration at 1000 meters
  • Use of existing A-19 shells
  • Maximum compatibility with ML-20S components
CAMD RF 38-11369-286: BL-9 against a 203 mm plate at 1000 meters. One shell penetrated completely, 4 shells are stuck in the armour, 3 shells left dents.

You may be thinking of the IS, but no, the tank that was first meant to carry this powerful gun was the KV. On October 26th, 1943, the Technical Department of the NKV held a meeting on the 122 mm OBM-51 tank gun proposed by OKB-172. The details are contained within CAMD RF 38-11355-1403.

"As ordered by the Tech-department of the NKV, OKB-172 developed a project for a modernization of the KV tank by installing a 122 mm gun. The modernization removes the current KV turret and all its armament, and replaces it with a new turret that holds a 122 mm high power gun, two machine guns, and the ammunition rack. The rest of the tank, all of its mechanisms, components, and armoured hull, including the turret ring, remain the same.

The 122 mm gun designed by OKB-172 has the following characteristics:
  1. Caliber: 122 mm
  2. Muzzle velocity: 950 m/s
  3. Shell mass: 25 kg
  4. Maximum gas pressure: 2660 kg/cm^2
  5. Barrel length with muzzle brake: 58.5 calibers
  6. Recoil resistance: 16 tons
The tank's turret consists of homogeneous rolled armour plates. Front: 75 mm, side: 60 mm, roof: 30 mm. In order to balance out the gun, the rear of the turret has 150 mm of armour. 

The gun is installed in the front of the turret on a welded mount. The mount and vertical aiming mechanism are borrowed from the SU-152 SPG with no changes. In order to balance the oscillating part of the gun, a hydromechanical balancing mechanism is planned. The turning mechanism is the same as in the KV turret. The tank carries 45 rounds of ammunition in the turret and on the bottom of the fighting compartment.

After discussion, we have come to the following conclusions:
  1. The modernization of the KV tank to equip it with a powerful 122 mm gun is a modern and reasonable course of action.
  2. The project is approved to continue to the prototype stage.
  3. It is reasonable to also adapt the modernization project, including the turret, to the IS tank.
  4. During development, it is suggested to:
    1. Use the D-5 mount, as it is the most compact.
    2. Use a horizontal sliding breech. 
    3. Increase the muzzle velocity to 1000 m/s on the IS chassis.
    4. Develop a cast turret variant, and make it as short as possible.
    5. Reduce the ammunition capacity to 30 shells to reduce turret height and mass.
    6. Allow for shooting on the move, move the fire button to the elevation mechanism. Implement a secondary electric fire mechanism.
    7. Reduce the tank mass to 45 tons.
  5. Give OKB-172 the highest priority, given the importance of this project.
  6. Suggest that OKB-172 work with naval armament factories."
As we already know, the lower velocity D-25T was chosen as the gun for the IS. Its penetration was entirely adequate for the German tanks that ended up being produced, and the high power 122 and 152 mm guns were ultimately not needed. 

Wednesday 12 June 2013

KV-1 and T-34 in England

A while ago, I wrote only on the impressions that the British had of the T-34 and KV-1 tanks they tested. Here is the full report, from the shipment to the trials.

CAMD RF 38-11355-1744

"In addition to the previously sent information, I report that tanks "T-34" and "KV" were loaded on June 13th, 1943, in the Bakaritsa port, on the steam transport "Empire Portia". At the same time, I report that there are differences in equipment, as follows:
  • The KV tank is lacking one magazine for the DT machine gun
  • The T-34 tank is lacking 18 magazines for the DT machine gun
  • The T-34 has the following extra components, not recorded in the proving ground documents:
    • crate of parts (no number)
    • konstalin (1 jar)
    • grease (2 jars)
    • tracks (140 links)
On both vehicles, the canvas sheets are very old, the one on the KV is torn in several places.
The discrepancies in equipment are noted in the attachment."

The several pages of attachment are, thankfully, also translated to English. How thoughtful!

The KV-1 sent to England is currently in the Bovington museum, with turret number 716 (belonging to another KV, serial number S-055). 

KV-1 tank on trials in England

The T-34 that underwent trials is not in the museum, but the preliminary study of the tank is available for purchase here

Curiously enough, they call it a cruiser tank. While it could conceivably be used in a cruiser role (that the British invented, and then gave up on), it was built for an entirely different purpose. 

Monday 10 June 2013

Spherical Tanks

A while ago, I translated an article about Soviet spherical tanks. Obviously (or not that obviously, considering how many hit from Google I got), the ShT-1A and ShT-2T were fakes. However, enterprising readers have actually clicked through the links and found that the article had blueprints of a spherical tank in it. That's because, while the history of spherical tanks in the article is a fabrication, actual spherical tanks are not.

At the beginning of the 20th century, futurists and engineers were hard at work thinking about the shape a fighting machine ought to take. Even the engineers settled on a shape we can all recognize as a "tank" in the 1940s (if you think it all ended at the FT-17, recall the unconventional shapes of the M3 Lee and T-35). People somewhat distanced from organized tank building still came up with exceptionally unconventional solutions.

The nature of CAMD RF is that every single document, no matter how insignificant, finds its way into the appropriate section of the archives once it has ran out of usefulness. For design proposals of "limited implementation potential", this was almost instant. CAMD RF contains a great many proposals for tanks that crawl, tanks that drill, tanks that fly (by catapult!), tanks that float, and tanks that roll. While I might eventually do an article on all sorts of crazy proposed designs, let's focus on some rolling ones for now.

The first actual spherical tank design, from 1917. It had no weapons, and could only combat the enemy by rolling at them, or having the crew shoot through an open hatch after stopping.

A German somewhat spherical tank project, surprisingly actually built and considered. It is also from an era when no one was quite sure how tanks are supposed to look like.

An American spherical tank project. These are the blueprints for the tank pictured on the Popular Science cover above.

Here is a colourful sketch of what one of the Soviet projects was supposed to look like. This is a pretty decent looking vehicle. It is very small for a tank, and has considerable firepower. Sadly, it is obvious that a tank of this configuration would easily tip over, and roll away. 

CAMD RF 38-11350-396

Yet another proposal, with only a machine gun. This one seems to be a lot more thought out. 

CAMD RF 38-11350-208

This design gives up any kind of tracks for a spiked, rotating hull. Not only would this be completely unsuitable for any kind of paved roads (or stopping), the size of the door and turret makes it apparent that this tank would be a giant and convenient target for aircraft and artillery.

This project, seemed more promising than all of the above ones:

"From Ashhabad, to the People's Commissar of Internal Affairs Comrade Beria,

A group of four scientists from the Turkmen Academy of Sciences approached us with a request to inform Comrade Stalin of a spherical tank they invented. Today, the first secretary of the Central Committee Fomin and I saw a model of this tank, shaped like a perfect sphere. The model easily traverses slopes, ditches, and has a high speed. The crew compartment remains stationary. The authors' ideas, in our opinion, deserve evaluation. Please advise. 

People's Commissar of the Turkmen SSR, Davydovskiy."

Looks like Davydovskiy had a higher opinion of the project than any real engineer. Judging by the handwritten notes, the project bounced around a little before getting shelved. According to Yuri Pasholok, the vehicle was built anyway, but later scrapped.

CAMD RF 38-11350-634

Another rolling tank, not really spherical. Yevgeniy Petrovich Zamoiskiy, a wine factory accountant, the mastermind behind this project, wrote: 
"I give you a sketch, with an explanatory note, of a round tank. The Red Army might use a few of these tanks. Advantages over a regular tank include:
  1. Good traction in deserts and sand (sand is its best road).
  2. Can easily traverse swamps, bogs, and can swim a significant distance.
  3. Spins in place (like a spinning top).
  4. It is a relatively light and voluminous simple object, and can be constructed from railroad fluid tanks.
  5. The tank can be made any size, with any armament. 

I am a simple accountant, and ignorant of blueprints, drawing, etc, so I could not, of course, illustrate everything in the sketch. If you need me to clarify anything, I can, given notice, ride to Moscow or anywhere else. 
Please instruct whichever Directorate is given this sketch to inform me of its work, as the Department of Inventions of the ArtKom GAU and NKO Invention Bureau, which I have given sketches of a "flying shell" and "flying car", have not graced me with an answer."
The note in the corner of the blueprint says "Note: not to scale. All I had for sketching were a glass, a jam jar, and a plank". 

This next project really cranks it up a notch. Instead of just a tank, it's more of a mobile fortress delivering tanks, men, planes, trains, just by rolling across enemy lines unimpeded. 

CAMD RF 38-11350-307

Spherical tanks aren't limited to Europe. This is an American spherical tank project from 1942.

The German "Kugelpanzer" (round tank) is stored in the Kubinka Tank Museum in Russia under the name "Item 37". It weighs 1.8 tons, has 5 mm of armour all around, and no armament. It achieves motion by two circular track mechanisms, with a single stabilizing wheel behind it. 

Sunday 9 June 2013

World of Tanks History Section: T28/T95

The Germans are credited with an unhealthy obsession with wonder-weapons. The Maus, Ratte, flying saucers, and many other interesting things come to mind. However, when you look at what was happening in the heads of engineers on the other side of the ocean, you can confidently place them in the same category.

Let us look at a curious example from the Americans.

In September of 1943, the United States begins their heavy tank program. US High Command thinks that these tanks will be necessary in order to penetrate fortified lines in Europe. This was correct, as the standard 75mm gun was insufficient for anti-fortification work. Existing medium tanks also lacked armour. At this point, the US only had one heavy tank, the M6, which was deemed ineffective as an assault platform.

Competing with the desire to create something large and fearsome, in the heads of many-starred generals was also a desire to complete the war with nothing newer than a Jumbo Sherman, which had better front armour than the Tiger. This competition led to no particular commitment to the heavy tank program. The Department of Artillery, under their own initiative, began working on a heavy tank in March of 1944.

The requirements for a new heavy tank came from the discussions of whether or not there should be a heavy tank at all. The front armour must be at least 200mm, the transmission must be electric, the gun must be the 105mm T5E1. This gun had a very high muzzle velocity, and could be used to destroy concrete fortifications.

The head of the artillery department insisted that before the second front opens (so in almost a year), he can not only develop a prototype, but provide 25 new tanks. This claim was very optimistic, this time would have barely been enough to make a prototype. High Command managed to make him see reason and ordered five prototypes, with the additional removal of the unreliable electric transmission, and its replacement with a mechanical one. In the end, the military downsized the order to two prototypes, because the war ended.

The new tank was named "T28". The front armour grew to 305mm, increasing the mass of the tank to 95 tons. Let's examine this American wonder closer.

The layout was, let's just say, non-standard. The tank was short, with no turret, resembling an ugly turtle. The T5E1 gun was placed in the front glacis plate. The horizontal traverse of the gun was 10 degrees, with 20 degrees of elevation and 5 degrees of depression. The crew consisted of four: a driver, a gunner, a loader, and a commander. The driver and the commander got cupolas on their hatches. The commander's cupola was also equipped with an AA mount for a .50 caliber machine gun. In order to reduce the ground pressure, the tank was equipped with a second set of tracks.

Upon viewing this design, the head of the department decided that this was not a tank, and suggested that it be renamed to "tank destroyer T95". This was explained by a lack of turret and weak secondary armament. This decision was accepted on March 8, 1945.

The T95 was a colossal vehicle, whose mass could not be carried by most bridges. The second pair of tracks allowed the tank to traverse cross country terrain, albeit poorly, while increasing the width of the tank. Movement was not easy for this beast due to the 500 hp Ford GAF engine, which was also used in the Pershing tank. A half the weight of a T95, 500 hp wasn't enough for a Pershing. The maximum speed this vehicle could reach was 12 kph, but it was decided that going past 10 kph is not recommended, as it was very hard on the engine.

The T95 couldn't go anywhere on its own. In Aberdeen, it underwent a total of 800 km of trials, in order to determine how long parts could last. Travelling that distance took a very long time.

In order to use this tank anywhere, it would have to be transported by railroad. In order to do that, the outside tracks had to be removed. This took anywhere between 2.5 to 4 hours, and as much to put them on afterwards.

It was unclear what should be done with this vehicle. Tanks were supposed to have turrets, and tank destroyers were supposed to be lightly armoured and fast. The T95 had a tank's armour, but no turret. After deliberations, the T95 was renamed to Super Heavy Tank, with its previous index T28. In 1947, work on the T28 stopped. This was tied to the fact that heavy tanks projects with turrets started springing up, and a mass of 95 tons was considered very high.

Only two T28s were built. In 1947, one was heavily damaged due to an engine fire, and was written off. The other broke down, and was scrapped. For 27 years, the only indication that this wondrous tank ever existed was in blueprints, until the first prototype was found on the territory of Fort Belvoir in Virginia. Currently, it is on display in the Patton Museum, in Fort Knox, Kentucky.

Original article available here.