Tank History - World War II
World War II did more than force armies to integrate all the available arms at every level into a mobile, flexible team. The mechanized combined arms force came of age in this war. In 1939, most armies still thought of an armored division as a mass of tanks with relatively limited support from the other arms. By 1943, the same armies had evolved armored divisions that were a balance of different arms and services, each of which had to be as mobile and almost as protected as the tanks they accompanied. This concentration of mechanized forces in a small nuaber of mobile divisions left the ordinary infantry unit deficient in both antitank weapons for the defense and armor to accompany the deliberate attack. The German, Soviet, and American armies therefore developed a number of tank surrogates such as tank destroyers and assault guns to perform these functions in cooperation with the infantry.
Armor experts in most armies, however, were determined to avoid being tied to the infantry, and in any event a tank was an extremely complicated, expensive, and therefore scarce weapon. The British persisted for much of the war on a dual track of development, remaining heavy tanks to support the infantry and lighter, more mobile tanks for independent armored formations. The Soviets similarly produced an entire series of heavy breakthrough tanks.
During the war, German tank design went through at least three generations, plus constant minor variations. The first generation included such unbattleworthy prewar vehicles as the Mark, (or Panzerkampfwagen) I and II, which were similar to the Russian T-26 and T series and to the British cruiser tanks. The Germans converted their tank battalions to a majority of Mark III and IV medium tanks after the 1940 French campaign, thereby stealing a march on the Soviets and British, who still possessed obsolete equipment. However, the appearance of a few of the new generation T-34 and KV-1 tanks in Russia during 1941 compelled the Germans to begin a race for superior armor and gunpower. The third generation included many different variants, but the most important designs were the Mark V (Panther) and Mark VI (Tiger) tanks. Unfortunately for the Germans, their emphasis on proteotion and gunpower compromised the mobility and reliability of their tanks. In 1943, for example, Germany manufactured only 5,966 tanks, as compared to 29,497 for the US, 7,476 for Britain, and an estimated 20,000 for the Soviet Union.
The alternative to constant changes in tank design was to standardize a few basic designs and mass produce them even though technology had advanced to new improvements. This was the solution of Germany's principal opponents. The Soviet T-34, for example, was an excellent basic design that survived the war with only one major change in armament, (76.2-mm to 85-mm main gun).
The United States had even more reason to standardize and mass produce than did the Soviet Union. By concentrating on mechanical reliability, the US was able to produce vehicles that operated longer with fewer repair parts. To ensure that American tanks were compatible with American bridging equipment, the War Department restricted tank width to inches and maximum weight to thirty tons. The army relaxed these requirements only in late 1944.
The devastating firepower and speed of the U.S. Army's armored divisions of World War II was largely the result of the genius of American industry. When Germany invaded western Europe in 1940, the US Army had only 28 new tanks- 18 medium and 10 light- and these were soon to become obsolete, along with some 900 older models on hand. The Army had no heavy tanks and no immediate plans for any. Even more serious than the shortage of tanks was industry's lack of experience in tank manufacture and limited production facilities. Furthermore, the United States was committed to helping supply its allies. By 1942 American tank production had soared to just under 25,000, almost doubling the combined British and German output for that year. And in 1943, the peak tank production year, the total was 29,497. All in all, from 1940 through 1945, US tank production totaled 88,410.
Tank designs of World War II were based upon many complex considerations, but the principal factors were those thought to be best supported by combat experience. Among these, early combat proved that a bigger tank was not necessarily a better tank. The development goal came to be a tank combining all the proven characteristics in proper balance, to which weight and size were only incidentally related. Top priority went to mechanical reliability and firepower. Almost as important were maneuverability, speed, and good flotation (low ground pressure). Armor protection for the crew was perhaps less important, although it remained a highly desirable characteristic.
The problem here was that only a slight addition to the thickness of armor plate greatly increased the total weight of the tank, thereby requiring a more powerful and heavier engine. This, in turn, resulted in a larger and heavier transmission and suspension system. All of these pyramiding increases tended to make the tank less maneuverable, slower, and a larger and easier target. Thicker armor plate beyond a certain point, therefore, actually meant less protection for the crew. Determining the point at which the optimum thickness of armor was reached, in balance with other factors, presented a challenge that resulted in numerous proposed solutions and much disagreement.
According to Lt. Gen. Lesley J. McNair, Chief of Staff of GHQ, and later Commanding General, Army Ground Forces, the answer to bigger enemy tanks was more powerful guns instead of increased size. And, in his high positions, General McNair understandably exerted much influence upon the development of tanks, as well as antitank guns.
Since emphasis of the using arms was upon light tanks during 1940 and 1941, their production at first was almost two to one over the mediums. But in 1943, as the demand grew for more powerful tanks, the lights fell behind, and by 1945 the number of light tanks produced was less than half the number of mediums.
Armor, as the ground arm of mobility, emerged from World War II with a lion's share of the credit for the Allied victory. Indeed, armor enthusiasts at that time regarded the tank as being the main weapon of the land army. In 1945-46, the General Board of the US European Theater of Operations conducted an exhaustive review of past and future organization. The tank destroyer was deemed too specialized to justify in a peacetime force structure. In a reversal of previous doctrine, the US Army concluded that "the medium tank is the best antitank weapon." Although such a statement may have been true, it ignored the difficulties of designing a tank that could outshoot and defeat all other tanks.
