The T-34's armour was considered formidable in the summer of 1941, as it was protected against the majority of German anti-tank guns. By the end of 1943, the balance tipped the other way. The light "doorknocker" 3.7 cm Pak and the occasional 5 cm Pak 38 were being forced out by the 7.5 cm Pak 40 and other high velocity weapons. An analysis of tanks knocked out in combat was performed in order to determine where the armour needs to be increased, but the results were rather disappointing.
"5. Possibility of increasing the T-34's resilience
The distribution of losses in tanks during the fighting near Orel from penetrations shows that losses of T-34 tanks are caused by the penetration of the following components:
Location | % of losses from penetration of armour | % of all losses |
Turret front | 22 | 17.6 |
Turret side | 18.7 | 15 |
Hull front | 21.5 | 17.2 |
Sloped hull side | 17 | 13.6 |
Upper half of the vertical side | 8.5 | 6.9 |
Total | 87.7 | 70.2 |
Table 12
In other words, in order to increase the resilience of the T-34 and radically increase its protection against German tank and anti-tank artillery, a reinforcement of all front and side armour is necessary. However, the T-34 tank is not capable of this due to weight restrictions.
Of course, it is incorrect to discount that the increase of thickness of one specific component won't reduce the amount of penetrations by some percentage. It is likely that a partial solution to this problem will result in the reduction of losses. The value of increased armour protection did not disappear. A partial solution of, for example, tank armour that makes it immune from the front, will reduce overall losses according to Table 12.
One of the most promising variants of increasing the T-34's armour would be the increased armour of the front of the turret and hull. The total area of these two parts is about 3.7 square meters. Additional armour to proof it from 75 and 88 mm German shells at short distances will add 1.5-2 tons of weight, including 600-800 kg in the front of the hull, and reduce losses by at least 30%.
Another variant is to reinforce the armour of the front and sides of the turret (3.3 square meters, weight about the same, reduction in losses by at least 25%). In this case, it would be enough to protect the sides of the turret from penetration by 75 and 88 mm rounds at an angle of at least 45 degrees.
If it is not possible to increase the weight of the T-34 tank, it is necessary to find the possibility to increase the armour. For this, it is necessary to review all components and find the needed weight by lightening unarmoured components and armoured components of the hull and turret rear.
6. Requirements for armour of prospective tanks
The overall percentage of losses from penetration (80% of all losses at Stalingrad and at least that much at Orel) shows that protection of tanks must be designed with real enemy weapons in mind, as well as real combat distances, which may be very short. The resistance of armour components must vary strictly based on its height and placement on the tank.
The front must protect at the shortest ranges (50-100 m). The sides must provide complete protection only at certain angles. These angles should be twice as big for the turret and 1.5 times as big for the turret platform as they are for the lower hull. The angles should be determined based on the tactics used in tank combat.
If weight is a pressing issue, the tank can be lightened by assuming that the following parts of the tank will not be hit by direct fire:
- Rear of the hull
- Rear of the turret
- Sides and front of the hull that are less than 600-700 mm off the ground."