Birth of the AT-45

"To member of the State Committee of Defense, comrade Beria L.P.

Currently, Voroshilovets tractors produced at factory #183 in Kharkov (375 hp engine, 35 kph maximum speed) are being used to tow heavy artillery. Since the evacuation of the factory to Nizniy Tagil in October of 1941, production of these tractors has stopped.

As a result, the Red Army lost the ability to refill its tractor park with powerful tractors, and, since 1942, does not even receive enough spare parts to support existing tractors of this type.

An increased demand in the Red Army for prime movers dictates that the production of powerful tractors must begin again. Factory #75 in Kharkov can be used for this purpose.

Since putting the Voroshilovets back into production requires redevelopment of all the tooling and will be time consuming, I propose that it is preferable to organize their production using T-34 mechanisms and components according to the "AT-45" technical project developed by factory #183 and approved by GAU in June of 1942.

I ask you to instruct the NKTP to produce an experimental batch of 5-10 AT-45 tractors by January 1st, 1944, and prepare for mass production in the first quarter of 1944 at factory #75 in Kharkov.

Chief of the GAU, General-Colonel of Artillery, Yakovlev."

CAMD RF 81-12086-40

Six tractors were eventually built, mildly misused, and then production wrapped up in favour of the T-44.

Tanks at the Mannerheim Line

"Technical Meeting Minutes

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

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

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

FCM36: Ahead of its Time

The FCM 36 was the least lucky French tank created in the interbellum period. Its design was progressive: it was the first tank with sloped armour to be put into production. While other French tanks were put together with bolts or rivets, FCM made its hull welded. In addition, the FCM 36 had a diesel engine. Alas, the fate of this interesting tank was a difficult one.

Medium Paper Tank Destoyers

Of all German E-Series (Entwicklung, development) only the E-100 ever reached the stage where it was ready to be built in metal. This did not stop other vehicles in the series from becoming very popular. These vehicles included not only tanks, but also tank destroyers, including the medium E-25 tank destroyer. Let us look deeper into its history and familiarize ourselves with other "paper" vehicles of its class.

World of Tanks History Section: Last Stand

A grenade and a bottle with incendiary fluid: this was the most widespread armament of a Red Army infantryman in late 1941. It was most effective where it was used with another powerful weapon: heroism. A well trained soldier could throw a bottle 20-30 meters, a heavy grenade bundle would fly even less. The bravest men closed in to this distance or even less, often paying with their life for a disabled or burned tank. On paper, this looks like a good trade, but in real life this is a tragedy.

Soviet engineers and simple citizens worked to make the heroisms of Soviet soldiers less fatal, sending their projects of simple and effective anti-tank measures.

Small Arm Rearm

CAMD RF 38-11355-806

"To the deputy commander of the Red Army GAU, Major-General of Artillery, comrade Hohlov

Experience shows that the 7.62 mm DT tank machinegun does not provide sufficient volume of fire, due to its 63 round magazine and rapid heating of the barrel. It is desirable to have a belt-fed machinegun, capable of rapidly firing up to 500 rounds.

The PPSh submachinegun is a necessary weapon for tank crews, but is inconvenient to use. The disk magazine is large, and gets in the way. The stock impedes exiting the tank. It is desirable to have a submachinegun with a box magazine that holds 25-30 rounds and a folding stock, like the one on the German SMG.

I ask you to instruct Artkom to begin work on improving firearms for tank crews according to the issues noted above.

Deputy GABTU Chief, Major-General of Technical Forces, Lebedev

BTU Military Commissar, Regimental Commissar Vorobyev"

The Real Matilda I

When seeing the term "Matilda I", many people imagine the awkward looking Infantry Tank MkI (A11). Matilda II evokes the image of the Queen of the Desert we know and love. But should it?

As you can see here, the Matilda I, Infantry Tank MkII, is armed with a 2-pdr gun and a Vickers machinegun, clearly the "senior" Matilda and not the machinegun-only A11. From this document, you can see that the Infantry Tank MkI never bore the name "Matilda".

Via Yuri Pasholok.

Tractor Clone

"Council of People's Commissars of the USSR
October 1945
Moscow, Kremlin

The Council of People's Commissars decrees that:

1. The Caterpillar model D-7 tractor is approved for production at the Kirov factory in Chelyabinsk under the index Stalinets-80 (S-80).
2. The Kirov factory is forbidden from making changes to the S-80 design, aside from changes necessary to begin production, and changes approved by the People's Commissar of Tank Production.
3. The production quota for the S-80 at the Kirov factory in Chelyabinsk is 10,000 units per year by 1949.
4. The People's Commissar of Tank Production (comrade Malyshev) and Central Planning must present the Council with a production plan and measures to aid in production of the Stalinets-80 (S-80) in 1946.

Chair of the Council of People's Commissars, I. Stalin

Affairs Manager of the Council of Commissars, Ya. Chadayev

Comparative characteristics of tracked diesel tractors D-7 and S-65

Tractor type		D-7	S-65
Nominal hp	Total power	92	82
	Useful power	80	65
Drag hp	Total power	73	65
	Useful power	61	50
RPM		1000	850
Gears	Forward	5	3
	Reverse	4	1
Speed (kph)	Slow gear	2.25	-
	1st gear	3.54	3.6
	2nd gear	5.15	4.85
	3rd gear	7.4	6.95
	Fast gear	9.7	-
Towing force, kg
At nominal power	Slow gear	9690	-
	1st gear	6100	5100
	2nd gear	4100	3500
	3rd gear	2700	2100
	Fast gear	2060	-
At drag power	Slow gear	7600	-
	1st gear	4800	4000
	2nd gear	3200	2800
	3rd gear	2100	1800
	Fast gear	1600	-
Fuel consumption, g/hp-hour		210	220
Mass (kg)	Tractor	11,000	11,200
	Engine	2000	2000
Ground pressure (kg/cm2)		0.5	0.5

"

CAMD RF 81-12086-265

The D-7 was adopted by the Red Army to tow even its heaviest artillery pieces.

CAMD RF 81-12086-251

Heavy How-to

"USSR NKO
Military Council of Armoured and Mechanized Forces of the Red Army
April 1st, 1944
#481904SS

To the commander of the 2nd Ukrainian Front, Marshal of the Soviet Union, comrade Konev.

The heavy IS and ISU-152 regiments sent to your disposal contain the first batch of tanks and SPGs of this type.

Both the tanks and SPGs have a series of small technical omissions. In addition, there is not yet sufficient experience regarding their use and application in combat.

IS tank and ISU SPGs are meant primarily to combat heavy enemy tanks and SPGs, as well as artillery, pillboxes, and dugouts in the depth of enemy defenses. Heavy regiments of both vehicles should be used as a part of tank and mechanized corps.

In battle, their place is in the second echelon. Medium tanks must protect their flanks from sudden attack by enemy tanks. In addition, each heavy tank and each SPG is guarded from tank destroyer groups by submachinegunners. Submachinegunners are included in the regiments (one company) at a ratio of five submachinegunners per tank or SPG.

At first, it is desirable to use these regiments on terrain that is suitable for tanks and accessible without great effort and, most importantly, take any measures to ensure that these tanks do not fall into enemy hands.

Keep in mind that the regiments do not have their own reconnaissance elements. As a rule, the unit that the regiment is cooperating with should provide scouts.

Tanks armed with 122 mm guns and SPGs armed with 152 mm guns can fire from either standstill, short stops, or ambushes at a range of 1.5-2 km. Tanks armed with 85 mm guns open fire during motion, from standstill, short stops, or ambushes from 1.2-1.5 km.

Since tanks with 122 mm guns and SPGs with 152 mm guns have small ammunition racks, it is necessary to arrange timely resupply in battle and use their ammunition wisely.

I especially ask you to give directions regarding timely technical inspection and correction of breakdowns in these vehicles.

In order to study the usage and combat characteristics of these tanks and SPGs, I send Lieutenant-General Taranovich and a group of officers. Please provide them with assistance.

Inform me of your impressions regarding the advantages and drawbacks of IS tanks and ISU-152 SPGs.

Commander of the Armoured and Mechanized Forces of the Red Army, Marshal of the Armoured Forces, Fedorenko
Member of the Military Council, Lieutenant-General Biryukov."

Via kris-reid.

IS-3 Green Light

"Conclusions

1. The IS-3 tank presented by Kirov Factory passed the 500 km long proving grounds trials. It did not pass the 1000 km warranty trial due to the fan breaking at 810 km.
2. The performance characteristics and reliability of mechanisms and assemblies of the IS-3 tank is equivalent to that of the mass production IS-122 tank.
3. The ballistics trials of the IS-3 hull demonstrate its obvious advantages over the hull of the IS-122 tank.
4. The modernized IS-3 tank is recommended for service under the condition that the defects in this report be resolved.

Deputy Chief, Scientific and Experimental Department of the NIBT Proving Grounds, Engineer-Colonel Sych

Chief of of the Tank and SPG Testing Department, Engineer-Lieutenant-Colonel Ivanov

Deputy Chief of of the Tank and SPG Testing Department, Guards Engineer-Major Bylinyak

Senior Assistant of the Chief of of the Tank and SPG Testing Department, Engineer-Lieutenant-Colonel Pankin

Senior Assistant of the Chief of the Armour, Armament, and Optics Testing Department, Grachev."

RGASPI 644-2-464

IS-2 vs. IS-3

"Comparative table of tactical-technical characteristics of heavy IS-2 and IS-3 tanks

	IS-2	IS-3
Combat weight (tons)	45.5-46.0	46.0-46.5
Length, hull (mm)	6770	6850
Full height (mm)	2730	2450
Full width (mm)	3070	3170
Clearance (mm)	470	465
Bore axis (mm)	1950	1800
Ground pressure on solid ground, kg/cm2	0.81	0.82
Armour protection, thickness and slope in mm/degrees
Upper front plate	90/60	120/55
Lower front plate	90/30	110/55
Side, vertical	90/0	90/0
Side, sloped	-	90/60
Rear	60/41-49	60/41-49
Turret front	100/0	240/0
Sides	100/20	115/45
Roof	30	20-30
Floor	20	16-20
Turret ring diameter	1800	1840
Armament
122 mm D-25 gun	1	1
DT machinegun	2	1
DShK AA machinegun	1	1
Gun ammunition	28 rounds	28 rounds
Engine
Diesel	1	1
Maximum power at 2000 RPM (hp)	600	600
Normal power (hp)	520	520
Range without refueling (km)	120-150	140-150
Transmission and chassis
Friction clutch	Multi-disk, dry
Gearbox	8 gear
Turning mechanism	Planetary, two step with friction stopper
Brake	Floating band type
Final drives	Planetary gear
Suspension	Torsion bar
Road wheels per side	6
Aiming and observation devices
Periscopic tank sight	T-Sh-14
Collimating sight	KV-T
MK-IV observation devices
Commander	1	1
Driver	2	1
Loader	1	1
Gunner	-	1

"

RGASPI 644-2-464

IS-3 Gunnery Trials

Since the gun of the IS-3 was the already well known D-25, the trials were rather brief.

"During gunnery trials, 37 fully charged shots were fired from the gun.

The recoil length was 520-530 mm, within normal limits.

No malfunctions of the gun occurred during gunnery or mobility trials.

The sight calibration was 2 thousandths off horizontally due to a weakening of the sight attachment screw.

The effort on the elevation mechanism was as follows:

• 0 degrees: 12 kg to lower, 9 kg to lift
• 5 degrees: 13 kg to lower, 8 kg to lift
• 10 degrees: 13 kg to lower, 8 kg to lift
• 15 degrees: 11 kg to lower, 11 kg to lift

Effort on the turret traverse handle when the tank is tilted:

• 0 degrees: 4 kg
• 5 degrees: 15 kg
• 10 degrees: 29 kg
• 15 degrees: 39 kg

The looseness of the gun is 4 thousandth vertically. The looseness of the turret is 6 thousandths horizontally."

The results of the firing were also recorded:

The radius containing the best half of the shells at 1000 meters is 33 cm. The radius containing all 9 shells fired is 40 cm, pretty close. For 2000 meters, the radii are 88 cm and 154 cm respectively. Not too far off from what was observed in the trials for the same gun on the IS-2.

RGASPI 644-2-464