Panzer III - Development History

Development History

On January 11, 1934, following specifications laid down by Heinz Guderian, the Army Weapons Department drew up plans for a medium tank with a maximum weight of 24,000 kilograms (53,000 lb) and a top speed of 35 kilometres per hour (21.75 mph). It was intended as the main tank of the German Panzer divisions, capable of engaging and destroying opposing tank forces.

Daimler-Benz, Krupp, MAN, and Rheinmetall all produced prototypes. Testing of these took place in 1936 and 1937, leading to the Daimler-Benz design being chosen for production. The first model of the Panzer III, the Ausf. A, came off the assembly line in May 1937, and a total of ten, two of which were unarmed, were produced in that year. Mass production of the Ausf. F version began in 1939.

Between 1937 and 1940, attempts were made to standardize parts between Krupp's Panzer IV and Daimler-Benz's Panzer III.

Much of the early development work on the Panzer III was a quest for a suitable suspension. Several varieties of leaf-spring suspensions were tried on Ausf. A through Ausf. D before the torsion-bar suspension of the Ausf. E was standardized. The Panzer III, along with the Soviet KV heavy tank, was one of the first tanks to use this suspension design.

A distinct feature of Panzer III, influenced by British Vickers tanks, was a three-man turret. This meant that commander was not distracted with either loader's or gunner's tasks and could fully concentrate on maintaining situational awareness. Most tanks of the time did not have this capability, providing the Panzer III with a potential combat advantage. For example the French Somua S-35, had only one-man turret crew, and the Soviet T-34 (originally) had two-men. The practical importance of this feature is signified by the fact that not only all the further German tank designs inherited it, but also later into the war, most of the Allied tanks' designs either quickly switched to the three-man turret, or were abandoned as obsolete.

The Panzer III, as opposed to Panzer IV, had no turret basket, merely a foot rest platform for the gunner.

The Panzer III was intended as the primary battle tank of the German forces. However, when it initially met the KV and T-34 tanks it proved to be inferior in both armor and gun power. To meet the growing need to counter these tanks, the Panzer III was up-gunned with a longer, more powerful 50-millimetre (1.97 in) cannon and received more armour although this failed to effectively address the problem caused by the KV tank designs. As a result, production of self-propelled guns, as well as the up-gunning of the Panzer IV was initiated.

In 1942, the final version of the Panzer III, the Ausf. N, was created with a 75-millimetre (2.95 in) KwK 37 L/24 cannon, a low-velocity gun designed for anti-infantry and close-support work. For defensive purposes, the Ausf. N was equipped with rounds of hollow charge ammunition which could penetrate 70 to 100 millimetres (2.76 to 3.94 in) of armour depending on the round's variant but these were strictly used for self-defense.

The Japanese government allegedly bought two Panzer III's from their German allies during the war. Purportedly this was for reverse engineering purposes, since Japan put more emphasis on the development of new military aircraft and naval technology and relatively little on the development of new tanks. The vehicles apparently weren't delivered until 1943 however, by which time much of the Panzer III's technology had arguably already become obsolete.