Balls of Soviet Tanks

Tank protection is developed based on information about anti-tank weapons of the potential enemy, physics of interaction between those weapons and a tank's armour, and the conditions in which tanks are used and that they fight in. An analysis of anti-tank weapons is a necessary step towards designing tank armour. In the 1950s it became clear that further improvement of tank protection simply through improving the characteristics of steel alloys is impossible. This was primarily true when protecting the tanks from HEAT warheads. The idea to use fillers to protect from HEAT ammunition appeared during the Great Patriotic War, but was not developed until after its conclusion.

The USSR's Hungriest Tank

Comparative trials of four Soviet tanks were conducted in the summer and fall of 1976 according to order of the Minister of Defense of the USSR D.F. Ustinov titled "On military trials of tanks" issued on July 20th, 1976. In September, a summary titled "Minutes of trials results" was composed. This article will discuss the contents of these documents.

T-64's Birthday

"Central Committee of the CPSU and the Council of Ministers of the USSR

Decree dated December 30th, 1966

Moscow, Kremlin

On the acceptance of a new medium tank into service with the Soviet Army

The Central Committee of the CPSU and the Council of Ministers of the USSR decree to:

1. Agree with the proposal of the Ministry of Defense of the USSR and Ministry of Defense Industry to accept into service with the Soviet Army a new medium tank, equipped with the 5TDF engine, 115 mm smoothbore D-68 gun with HEAT, HE, and subcaliber armour piercing ammunition, a 2318 two-plane stabilizer, a TPD-43B rangefinder sight, and a PKT coaxial machinegun developed in accordance with CC CPSU and Council of Ministers decree #141-58 dated February 17th, 1961 and matching tactical-technical requirements given in attachment #1.

Name the aforementioned tank T-64."

"Comrade N.A. Kucherenko 

Copy into the order.

V. Bakhirov

January 4th, 1967"

Via Andrei-BT

T-64A's Birthday

"Central Committee of the CPSU and the Council of Ministers of the USSR

Decree

May 20th, 1968

On the installation of a more powerful set of armament into the T-64 tank.

The Central Committee of the CPSU and the Council of Ministers of the USSR decree that:

In agreement with the proposal of the Ministry of Defense of the USSR and the Ministry of Defense Industry of installing into the T-64 tank a new 125 mm smoothbore D-81 gun with armour piercing subcaliber, HEAT, and HE-fragmentation shells, two-plane stabilizer 2E23, TPD-2 rangefinder sight, and a PKT coaxial machinegun with main characteristics in accordance to attachment #1.

The T-64 tank with new armament will be called T-64A."

Via andrei_bt.

Penetration Part 10: Cold War Subcaliber

I already posted penetration intel on Soviet post-war guns, but there were a lot of holes in that table. Let's skip a few years to another upgrade to the Soviet arsenal, the 125 mm smoothbore gun, and check our numbers again.

P.P. Isakov, Theory and Design of a Tank, 1982

Parameter	Type of shell (Gun)
	3BM11 (M-62)	3BM9 (D-81)	3BM15 (D-81)
Caliber, mm	122	125
Type of shell	Rotating	Fin stabilized
Shell mass, kg	7.4	5.67	5.9
Core mass, kg	2.8	-	0.26
Muzzle velocity, m/s	1575	1800	1785
Muzzle energy (kJ)	9200	9200	9400
Penetration at 2000 meters at an angle from normal of:
0 degrees	320	245	400
45 degrees	190	185	200
60 degrees	110	140	150

The M-62 blows its AP performance out of the water. However, you can see that this is an era of HEAT, as the American intelligence talked about a 460 mm penetration HEAT shell. The subcaliber ammunition of the 125 mm gun is no slouch, however. The mediocre performance of 3BM9 is due to the shell being made from high hardness steel. Once tungsten carbide ammunition is used, the penetration soars to 400 mm, more than enough to combat any tank of the era.

Via andrei-bt.

Some T-64 Drawings

Livejournal user armor_kiev_ua posted some drawings of the Object 432 (that would later become the T-64).

First is a comparison in size between the M60 Patton (the hypothetical enemy's best and scariest tank at the moment) and the new Soviet tank.

The second is a bit more interesting, showing the composite armour of the hull and turret.

Modern Soviet Tank Ergonomics

The Armoured Journal yields another article of interest, this time on human factors of tanks by M.N. Tikhonov and I.D. Kudrin: Human Factors and Scientific Progress in Tank Building, submitted on May 18th, 1991. The article mostly contains very general thoughts on things that are rather obvious to us now (ability to fight in irradiated environments, tanks that are able to drive for longer without stopping being more tiring for their crews, etc), but there is a table of something we've seen before, a table of ergonomic factors of some tanks!

Table 2. Volume occupied by one crewman in a tank, meters cubed.

Only the volumes are given this time for various tanks (commander, gunner, driver, loader, who is of course absent in the T-64 and T-72). It's not as detailed as what we've seen before, but at least we can compare these four tanks.

Comparing the heavy and medium contemporaries, the heavy T-10 and medium T-55, one might expect the heavy tank to be roomier, but no such luck here. The volumes for each crewman are comparable. The commander in the T-10 has a slightly more luxurious workspace, but its gunner is slightly more cramped. The driver of the T-10 also has a slight edge over his medium comrade, but the loader in the T-55 lives a life of royalty, as he has nearly twice as much space to work with as the T-10 loader. 

Moving on to the next generation, the changing of priorities is noticeable. The article talks about how increasing penetration of modern ammunition tipped the scales away from armour. The most effective defense, now more than ever, was "don't get hit", and Soviet tanks became shorter and stouter to avoid this fate. However, the loss of one crewman meant that the change didn't impact the crew too negatively. For instance, the commander's workspace decreased to the levels of a driver of the old generation tanks, but the gunner's workspace actually grew in side by a significant amount. There was also much more room for the driver.

As for the two modern tanks, they aren't too different. The "budget" T-72 is a little smaller across the board than the T-64. The commander barely loses any space at all, but the gunner and driver both suffer significantly more. Still, they are doing much better than their T-55 counterparts.