General Heinz Guderian, building on experience gained in the design of the Panzerkampfwagen I (Pz.Kpfw I), pushed hard for the mainstay of his Panzer divisions, a new 15-ton light tank -- the Panzerkampfwagen III (military designation, SdKfz 141).
Production began in 1936, but manufacturing went slowly as Guderian fought the army's bureaucracy, the Nazi government's shifting priorities, and a shortage of raw materials and design experience.
A number of prototype vehicles were tested before the design was standardized in September 1938. By December 1939 only 157 Pz.Kpfw IIIs had been built.
The Pz.Kpfw III was not a major advance in tank development. Rather, it was specific to the tactics Guderian had in mind.
It had a high-velocity gun (the 45-caliber 37mm antitank gun used by the infantry), a crew of five so that each member would not be overwhelmed by a multitude of tasks when under fire, a radio and intercom system, a ten-speed transmission, and a vastly improved suspension and road wheel system.
To keep weight within reasonable bounds, armor was kept at the same thickness as that used in the early models of the Pz.Kpfw II.
In the matter of main armament, Guderian was forced to compromise. He had wanted a 50mm high-velocity gun, but Ordnance insisted on the 37mm infantry antitank gun in the interests of standardization. However, the turret ring was made large enough so the tank could be up-gunned at a later date.
The interior design of the Pz.Kpfw III was exceptionally well thought out -- as it had to be for a crew of five. The tank commander and gunner sat in the revolving turret compartment. The driver sat forward on the left side in the main hull; the radio operator to the rear. The loader had sufficient room to stand and move the heavy shells from storage bins to gun.
Only a small number of Pz.Kpfw IIIs took part in the invasion of Poland in the fall of 1939. But on May 8, 1940, most of the 349 Pz.Kpfw Ills that had been built were operating in the XIX Panzer Corps, which was responsible for the breakthrough in the Ardennes region.
The minimal armor and 37mm gun were no match for the French Char B Heavy Tank or the S-35 Medium Tank on a one-to-one basis, but concentration of forces and superior tactics enabled the Nazi Germans to run right over Allied tanks operating in support of infantry.
At one point, General Erwin Rommel was able to move his armored forces 175 miles in one day, a record that still stands.
See the next page to follow the evolution of the Panzerkampfwagen III.
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