"Tendencies in the manufacturing of German armour plates (excerpts from the report prepared by the Head of the Main British Tank Development Directorate)
The testing of a Tiger tank recently brought to England showed a deviation from typical German armour protection techniques. None of the armour was surface hardened. The hardness on the Brinell scale is as follows:
- Thin horizontal plates (26 mm thick): 298-343
- Thick nearly vertical plates: 257-310
The fact that the armour is no longer surface hardened, and has a relatively low Brinell hardness, is very important. It must be noted that this change coincides with the appearance of new German heavily armoured tanks: Tiger, Panther, Ferdinand. Until now, no German tank had armour thicker than 50 mm.
The deviation from existing practices is explained by the following reasons, or their combination.
- Economic reasons. It is very possible that the very amount of armour overloaded the German capacity to manufacture it, and Germany was forced to utilize heavier manufacturing, usually tasked with manufacturing simple armoured plates. There might be a shortage of equipment capable of processing thick armoured plates.
- Mechanical finish problems. The three aforementioned vehicles have interlocking armoured plates to increase the strength of the welds. Regular step connections were preserved. The combination of these two connections reduced the ability to produce a large number of armoured hulls. Perhaps the softer plates were introduced to remedy these problems.
- Ballistic factors. The three aforementioned vehicles were built for the purpose of long ranged combat. It is possible that the enemy introduced softer armoured vehicles knowing that the Allies use armour piercing capped shells. Use of these shells against soft armour is suboptimal. If soft armour continues to be used, we must explore the question of ballistic caps. However, it is necessary to collect more information, as this armour could still be surface hardened.
It is necessary to examine a Panther tank and perform experiments on armour of Tiger tanks built later than the one mentioned in this report."
The report came out in January of 1944, so not many Tigers were built after that. The Americans, meanwhile, tested the armour of the Panther. Their findings spoke rather poorly of German manufacturing. Their findings were the same as what any of my readers have already seen: German armour is of poor toughness, and their welding seams have a tendency to burst under pressure.