Thursday 29 June 2017

Tetrarch Delivery

"Contents: delivery of supplies to the USSR by the south route
December 27th, 1941

To: General Panfilov
CC: General Fedorenko

I received a report that the light tanks which we delivered through Persia arrived in Zanjan, where they are being transferred to Soviet authorities.

I am being told that training of Soviet personnel with these tanks will happen in Zanjan. I am also being told that an officer of the British Mission in Tbilisi is being sent to Zanjan to help.

I would like to know if everything is going well or if you have some issues that demand my attention.

Lieutenant General [signature]
British Military Mission

Wednesday 28 June 2017

On the Way to the SU-122

"To factory #8 director comrade Fratkin
CC: Chairman of the NKV Technical Council, regional GAU KA engineer at factory #8, Engineer-Colonel Kascheev

RE: development of self propelled howitzers.

Regarding the issue of designing a 122 mm self propelled M-30 or U-11 howitzer on the T-34 chassis, in accordance with the NKTP, I report that:
  1. The turret platform of the T-34 tank can be extended to span the length of the hull, and the sloped sides can be placed vertically.
  2. The fuel tanks can be located in the engine compartment. As a last resort, the shape of the fuel tanks can be changed
  3. It is not permitted to change the hull of the T-34 tank or  the layout of the engine and transmission.

Tuesday 27 June 2017

French Tanks in German Service

"Use of French Armoured Vehicles by Germany

A series of low altitude photographs of large tank parks at Gien and La Brosse gave valuable information regarding the types of French armoured vehicles in use by Germany.

Monday 26 June 2017

Soviets vs M48 Patton

Fig. 2 Tactical diagram of complete penetration and satisfactory penetration limits when firing at an M48 tank with domestic 85 mm sharp tipped capped armour piercing shells.
Muzzle velocities higher than stock were tested at 100 meters with an increased charge.
  1. Complete penetration limit of the lower front hull.
  2. Rear plate integrity limit of the lower front hull.
  3. Complete penetration limit of the upper side of the hull.
  4. Rear plate integrity limit of the upper side of the hull.
  5. Complete penetration limit of the lower side of the hull.
  6. Rear plate integrity limit of the lower side of the hull.

Saturday 24 June 2017

T-60 From Stalingrad

The T-34 tanks built in Stalingrad became one of the symbols for the battle there. The last tanks produced where went straight into battle from the factories, crewed by factory workers. T-60 tanks were less noticeable contributors to the breaking of the backbone of the German blitzkrieg. At the outskirts of the city, in Krasnoarmeysk, the T-60 tank remained in production at factory #264 for less than half a year. However, by volume of production, this "unplanned" factory was second only to the Molotov GAZ.

Friday 23 June 2017

T-60 in Difficult Times

On July 20th, 1941, the State Committee of Defense (GKO) passed decree #222ss "On the production of 10 thousand light tanks". Interestingly enough, the tank that was supposed to be built did not exist even on paper. The tank, later named T-60, was designed in a little over a week. The first tanks were built in September of that year, and full fledged mass production began in October. The Molotov Gorkiy Automotive Factory (GAZ), Kharkov Tractor Factory (HTZ), and factory #37 were tasked with producing these tanks. Meanwhile, reports coming in from the front indicated that the tank was in need of modernization. What problems did the tankers reveal, and how did Soviet engineers try to solve them?

The One Without the Rifle Follows

"Moscow, Kremlin
To Comrade Poskrebyshev

Operational group of the Western Front HQ, Kransodar
December 21st, 1941, 11:30

I ask you to report to the People's Commissar that out of all the weapons bought in Iran (10 million rounds, 100,000 rifles, 600 handheld and 300 mounted machineguns as of December 21st), 21,600 rifles and one million rounds of ammunition arrived to Qazvin.

The shortage of arms on the Western Front, including the three newly forming divisions and one brigade, is 126,000 rifles, 4,750 handheld machineguns, and 2,460 mounted machineguns.

I ask that all weapons bought in Iran be left for the Western Front, which will allow us to arm the newly forming divisions and brigade with domestic weapons and equip rear line units with Iranian weapons.

D. Kozlov

Via kris_reid.

Wednesday 21 June 2017

ZIS-5, Take One

"May 30th, 1941
To the Central Committee of the VKP(b)
Comrade Zhdanov

According to USSR SNK and Central Committee Decree #1216-502 issued on May 5th, 1941, two experimental T-44 tanks built by factory #183 are supporsed to be armed with the 76 mm ZIS-5 or 57 mm ZIS-4 gun. The main characteristics of these guns is shown in the following table:

Gun model
Caliber in mm
Muzzle velocity, m/s
Shell mass, kg
Penetrates armour
At 0 degrees
At 30 degrees
Thickness in mm
Distance in m
Thickness in mm
Distance in m
Up to 1000
Up to 1000
Up to 1000
Up to 1000
Up to 1000
Up to 1000

Tuesday 20 June 2017

Torsion Bar Trials

"Methodology of Torsion Bar Trials

The trials were split into stages:
  • Motion trials of torsion bars.
  • Lab tests of materials (static and spring fatigue).
  • Lab static destruction tests of torsion bars (by twisting).
  • Analysis of various layouts of torsion bar suspensions and issues connected with them.

Monday 19 June 2017

KV Gun Upgrades

"The following work is necessary to perform trials of KV tank armament and improvement of blueprints:
  1. Install the F-34 gun instead of the F-32 gun into the KV-1 tank at factory #92 by March 1st, 1941.
    A commission composed of representatives from ChTZ, the Kirov factory, GABTU, and GAU must perform trials and approve blueprints by March 5th, 1941. Factory #92 received a KV tank with a 76 mm F-32 gun on February 2nd, 1941.
  2. Install the 107 mm F-42 gun instead of the M-10 gun into the KV-2 tank by May 1st, 1941. Perform trials and work on blueprints, presenting them to the NKO no later than May 15th, 1941. Factory #92 received a KV tank with a large turret on January 29th.

Sunday 18 June 2017

Praga LTL and Pzw 39: Tanks for Neutrals

In May of 1935, an Iranian commission signed a contract with CKD for light Praga TNH tanks. At the moment, these tanks did not exist in metal, but the Iranians saw the potential in this design. A prototype was demonstrated in September of that year. The Iranian commission was so impressed that the order was increased to 50 tanks on September 10th. For this time, this was a very respectable amount of tanks for the export market. It's not surprising that representatives from other nations came to Czechoslovakia to find inexpensive and high quality light tanks. CKD's engineers managed to satisfy their new customers, creating new tanks for Lithuania and Switzerland, known as the Praga LTL and Pzw 39.

Saturday 17 June 2017

LT vz. 35: Steel Fist of the First Czechoslovakian Republic

On April 19th, 1933, the Czechoslovakian army signed a contract with CKD to produce 50 light P-II tanks. This ended the 10 year long quest to build a domestic tank. The tank accepted into service on July 13th, 1935, as the LT vz. 34 was sufficiently modern. However, a year later, the Czechoslovakian military needed a better protected tank. This tank, the LT vz. 35, was destined to become the backbone of the Czechoslovakian armoured forces.

Thursday 15 June 2017

German Tank Fear

"Anti-Tank Defenses

14. The fear of massed enemy tank attacks still grips the soldiers, especially among the young and inexperienced replacements, to the point of mental breakdown. As a result, soldiers often leave anti-tank foxholes and positions, which lets enemy tanks cause significant losses and the Russian infantry to take our positions without battle.


Training, among replacements as first priority, must harden young soldiers, especially infantrymen, against the mental effect of tank attacks. Every soldier must know that when he leaves his positions or foxhole, he becomes defenseless against tank fire, but a well prepared foxhole or, even better, a deep slit trench offer reliable protection against the weight and fire of tanks. It is necessary to take every opportunity to teach soldiers to let the tank pass above their trench using our tanks, assault guns, tractors, or captured tanks. It's necessary to prove the limited amount of visibility, and therefore precise fire, on the move from a tank. Every soldier must sit in a tank at least once."

Wednesday 14 June 2017

PzIII Shortage

"June 20th, 1942
To the Deputy People's Commissar of Defense and GABTU Chief, Lieutenant-General of the Tank Forces, comrade Fedorenko
Moscow, 2nd NKO building

An experimental SPG on the chassis of a captured German StuG SPG, equipped with a 122 mm divisional howitzer mod. 1938 "M-30" was built according to orders from the Artillery Committee by factory #592.

Tuesday 13 June 2017

Ultra Gun

The Department of Inventions was flooded with a great deal of proposals from the population, most of which received an answer similar to this one. However, a small fraction of the inventions were actually useful. Even if they were never implemented in metal, the USSR recognized the contributions of its citizens.

"To the Chief of the Central Planning Department of Inventions of the SNK

RE: Decision regarding the issue of a patent for claim #1582s

Having inspected the description, drawings, and all documents related to the request of citizen S.D. Bogoslovskiy, registered at the NKV under #1582s on April 23rd, 1942, under the title "Bicaliber barrel and shell, specially designed for an anti-tank gun", the Inventions Section of the Technical Council of the NKV decided to issue a patent for a gun barrel that fires "Ultra" shells with the following description:

Monday 12 June 2017

What's in a Name?

There are a few examples where the real name of a tank or gun sinks into the sands of time, replaced by a more popular, yet incorrect one. The Renault FT is another example. More often than not, you see the tank called "FT-17", rarely "FT-18". Looking at production codes at Renault, the number was never included. For example, the Renault FT was preceded by the Renault FS, a car, and succeeded by the Renault FU, a heavy truck. However, even serious sources attach a number to the tank's name. Where did the number come from?

German documents regarding the Renault FT use the extra numbers.

Sunday 11 June 2017

Renault D2: De Gaulle's Workhorse

The heavy Char B1 tank became the symbol of French pre-war tank building, and General de Gaulle is frequently associated with it. The 36 ton tank might have been the best French tank was indeed the best tank that France had during the fighting of May-June of 1940. The tank's thick armour worked well, even though the concept of the tank was obsolete.

Interestingly enough, mass production of the Char B1 might never have happened, since the French military was considering a different tank for the role of their main tank in the early 1930s, with the same armament, same armour, but more than 1.5 times lighter. This was the Renault D2, the tank that Colonel De Gaulle served in.

Saturday 10 June 2017

Renault D1: FT on Steroids

Attempts to modernize the Renault FT, the most numerous tank in WWI, gave unexpected results. Initially, only the low speed was unsatisfactory for the French military, but its tastes grew by the mid-1920s. Now, the thin armour, which was insufficient to protect the tank from high caliber machineguns, was also unsatisfactory. The result was the NC-1 tank, which was 2 tons heavier and had thicker armour, while being twice as fast. The tank was a good replacement for the Renault FT, but the army's appetites grew once more, which led to the creation of a new tank, the Renault D1.

Thursday 8 June 2017

KV-1 Engine Compartment

Details of the famous Aberdeen test are still not fully available online, all we have are scraps and rumours. However, user Makarov from Tiger's Corner shared a little bit of it with us. These high resolution photos of the engine and transmission compartments are sure to delight any dedicated scale modeler.

Fans of the "JS" vs "IS" debate will also both certainly be shocked at the new name the tank received in this report: KB.

Wednesday 7 June 2017

Tukhachevsky on Tanks

A man like Mikhail Tukhachevsky needs no introduction, as he is one of the most famous military minds of the 20th century, having come up with the very effective Deep Battle doctrine. However, some of his ideas were rather odd, even for their time.

"In my note on tanks, I wrote: "If we take Magdesiev's calculations as 50%, then with our plans for tractor production in 1932/33 of 197,000 units, the annual tank production can be 100,000. If we consider one year of war to consume 100% of tanks (this is an arbitrary number), then we can maintain a park of 50,000 tanks."

Tuesday 6 June 2017

Cromwells in Normandy

"Remarks regarding the use of Cromwell tanks in Normandy

1. Exhaust fumes, exhaust system, sparkplug fouling

A. The tank's users discovered that the exhaust fumes of the tank gave away the tank's position in moist weather. 

In order to immediately prevent this from happening, a protective cap for the exhaust pipe was designed. It is easy to install and it's made from scrap metal and refuse. The latter is used as stuffing.
This cap has the following advantages:

Monday 5 June 2017

KV-3 Evolution

"To the BTU Chief, Military Engineer 1st Class, comrade Korobkov

I report that the Kirov factory made the following decisions on the KV-3:
  1. The KV-3 will be based on the Object 221 with a future plan of increasing the side armour once an 850 hp engine is received.
  2. The armament, front, and turret armour will be increased according to State plans.
  3. Since the hulls of the Objects 220 and 221 are identical in dimensions, the transmission from the 220 will be installed in the KV-3 with the V-5 engine (700 hp) with the intention to replace it with an 850 hp engine.
  4. Trials of the V-5 engine, transmission, and KV-3 suspension will be performed on the Object 220.

Sunday 4 June 2017

Canon 25 mm S.A. Mle 1934: A "Baby" Gun for a Grown Up War

An old military saying states that "every army prepares to fight the previous war". That is how the French generals acted when planning new anti-tank guns. Thinking about enemy tanks, they envisioned clumsy boxes, crawling across the battlefield at a pedestrian's pace, protected with several centimeters of armour. To fight them, a small gun was needed, one that could be easily hidden on a crater-pocked field and pushed around with just the strength of the crew. The result of this line of thinking was the 25 mm anti-tank gun model 1934, Canon 25 mm S.A. Mle 1934.

Saturday 3 June 2017

Renault R 40: Incorrigible

The Char leger Modele 1935 R that was accepted into service by the French army on April 25th, 1935, was a compromise. Created as a replacement for the Renault FT, it did not surpass its predecessor by much in speed, and the armament remained the same. Of course, the new tank had more powerful armour, but experience showed that you could not rely on it. The French infantry began looking at the FCM 36, an expensive tank, but one that was more suitable for the infantry tank role. The Renault R 35 could only be rescued with a modernization of its weakest link: the suspension. A new tank with a superior suspension and a longer gun received the index R 40. It finally satisfied the requirements of the customer, but it was too late.

Thursday 1 June 2017

SS Professionalism

"There's an interesting moment at the start of the Vienna operation that should be remarked on, regarding the issue of highly trained SS units. The Germans saw the preparations. Even though the weather was bad, their reconnaissance aircraft were flying and saw a concentration of cars, tanks, artillery, and tracked it. They could precisely predict that an offensive was about to start. The first round of fighting was with the Fuhrer, who was told that the Spring Awakening had to end, now the Russians are going to hit us and that's it, the front will collapse, we're going to have an "awakening" with hangover, as they say. They tried to convince Hitler for a while, convinced him in the end (it was still Guderian then as the Chief of Staff). Guderian convinced Hitler to wrap up Spring Awakening since it didn't achieve any results. The Fuhrer agreed that it had to wrap up to prepare for the Russian offensive. With a load off his shoulders, Weller, the Commander of Army Group South calls Dietrich's HQ and says "That's it, the Fuhrer allowed it, we can retreat, now the Russians will attack", to which he received a cold answer: "Well you see, it's already evening (March 15th), we can't get in touch with our people and pull them back, let's do it tomorrow, tomorrow night, to conceal our movement." A whole day was lost purely out of exceptional incompetence, I have no other word for it, on behalf the 6th SS Tank Army staff."

Aleksey Isayev, "The Nazis' Last Counteroffensive"