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M4 General Sherman

The M4 General Sherman was the main battle tank designed and built by the United States for the conduct of World War II. the 32-ton M4 General Sherman tank presented a radically new design; it was the first U.S. tank to have an all-welded (instead of riveted) body, and the first to carry its main gun on a 360-degree rotating turret.

The M4 was the most widely used tank series in the war, being employed not only by the US Army and Marine Corps but also by British, Canadian, and Free French forces. The M4 was employed in North Africa, Sicily, Italy, and western Europe and throughout the Pacific Theatre. A total of 49,324 tanks was produced in 11 plants between 1942 and 1946.

Chrysler manufactured about 18,000 M4s from the summer of 1942 through the summer of 1944. Production of the M4 required considerable manufacturing flexibility in its own right, because the same basic tank was equipped in a variety o1 ways. There were seven different models of the M4, including tanks powered by several engines; various models were equipped with 75 and 90 mm guns, 105 mm howitzers, special artillery cannons, mine detectors, and related accessories.

The Army fought World War II with the M4 Sherman as its primary tank. The Sherman was optimized for infantry support, reliability, and ease of manufacture, while the Army relied upon the unproven concept of purpose built tank destroyers to fight enemy Armor. In combat, the Sherman quickly found itself overmatched by German panzers designed for fighting other tanks. After investing in a flawed concept, the Army had to adapt tactics to counter superior German tanks with the Sherman. While combined arms, tactical air support, and overwhelming sustainment and numbers enabled Army divisions to maneuver to defeat the German Army, American tankers typically lost three or four Shermans for every German tank they destroyed.

US doctrine for employing armored divisions foresaw tank destroyers, not tanks, defeating enemy armor. Chance encounters between tanks might occur, but the primary role of the armored division was to exploit and pursue, not fight enemy armor. The Sherman's low-velocity 75 or 76 mm gun was chosen because the Army's artillery branch wanted a cheap, reliable weapon for fire support.

For all these reasons, the US Army standardized on the M4 Sherman medium tank, an excellent compromise between reliability, mobility, armor protection, and gunpower. When the British first employed the Sherman in North Africa during late 1942, it proved to be at 1east equal, if not superior, to the German second-generation tanks, Mark III and IV.

In 1939, the year that German armored columns streaked across Poland, the US Army budget for tank research and development was only $85,000. Such parsimony forced hard choices that often degraded combat capabilities. The Shermans low-velocity 75 or 76 mm gun, for example, was chosen because the Armys artillery branch wanted a cheap, reliable weapon for fire support. In another cost-cutting move, many M4s were equipped with a radial engine originally designed for aircraft. On the battlefield, this engine produced a loud backfire when starting, instantly drawing enemy fire.

The width limitation hampered the Sherman by forcing designers to give the tank narrow tracks. These tracks had much less mobility in muddy terrain than the wider tracks used by the Soviets and Germans. The M4's only advantages over later German tanks were superior reliability and a power-driven turret. During meeting engagements at close ranges this latter feature allowed the Sherman's crew to traverse their gun and engage the enemy more rapidly than could German crews using hand-cranked turrets. Sherman tank crews often carried a white phosphorus round in their guns to blind enemy tanks during such maneuvers.

Once the Tiger tank appeared in Tunisia in early 1943, however, the Sherman tank and most of the US antitank force seemed inadequate. The Sherman was badly outclassed by German medium and heavy tanks, most notably the Mark V Panther and the Mark VI Tiger. With their heavier armor, the Panther and Tiger were almost impervious to rounds fired from the Sherman's 75 or 76 mm main gun; conversely, the 88 mm gun on the German tanks usually made short work of their American opponents. Although these observations are commonplace, they reflect a mis-understanding of American armor doctrine of the time. Enemy tanks were to be countered, not by American tanks [such as the Sherman], but by dedicated anti-tank tank-destroyer units, such as the M18 Hellcat, built on the chassis of the Sherman tank. US doctrine did not embrace the concept of tank-on-tank combat until 1946. US anti-tank crews outmaneuvered their foes, disabling the German tanks with a shot against their sides or rear, where the armor was thinner.

The M4 Sherman tank was no technological match for German armor, but this was not because the United States could not design and build a better tank. It was because the Sherman tank fit easily into Liberty ships, and a major change in design would have meant severely reduced production while factories retooled for the new model. Although it was no match for German heavy tanks in firepower and armor protection, the M4 medium, with its superior mechanical reliability and capacity for traversing rough terrain, especially in mountainous areas, was the workhorse of the war. Employed in practically every conceivable way that a tank could be used, it performed the infantry-accompanying role, it operated as light cavalry, it spearheaded armored attacks, it played an antitank role, and it functioned as auxiliary artillery.

In early 1944, the US Army faced a critical decision regarding its armored forces: should it retain the M4 Sherman as its primary tank or accelerate production of the new M26 Pershing heavy tank? Although many armored commanders favored the Pershing, the tank debate continued until Lt Gen George S. Patton, the Armys leading tank "expert," entered the fray. Patton favored the smaller (and supposedly more mobile) Sherman, noting that "tanks were not supposed to fight other tanks, but bypass them if possible, and attack enemy objectives in the rear." Ultimately, senior Allied commanders including Gen Dwight Eisenhower backed Patton and decided to increase production of the Sherman. It remains one of the most disastrous choices of World War II arguably, a decision that lengthened the war and became a literal death sentence for thousands of tank-crew members.

The consequences of the Sherman decision are brutally detailed in Belton Coopers vivid memoir Death Traps. A maintenance officer who served in the legendary Third Armored Division ("Spearhead"), Cooper was charged with the critical task of locating damaged Shermans, directing their recovery, and ensuring the flow of new or repaired tanks to frontline units. American tank crews discovered in combat the Sherman was badly outclassed by German medium and heavy tanks, most notably the Mark V Panther and the Mark VI Tiger. With their heavier armor, the Panther and Tiger were almost impervious to rounds fired from the Shermans 75 or 76 mm main gun; conversely, the 88 mm gun on the German tanks usually made short work of their American opponents.

Over the next 11 months, the Third Armored Division, which began the Normandy campaign with 232 M4 tanks, would see 648 of its Shermans destroyed in combat, with another 700 knocked out of commission before being repaired and returned to servicea cumulative loss rate of 580 percent. Casualties among tank crews also skyrocketed, producing an acute shortage of qualified personnel. By late 1944, Cooper recalls, the Army was sending newly arrived infantrymen into combat as replacement tank crews. Some of these recruits received only one day of armor training before being dispatched to the front in their M4s.

Despit its drawbacks, the Sherman remained the main battle tank of the US Amy. General Eisenhower remained convinced of the high quality of the M4 Sherman tank until newspaper accounts detailing NCO and junior officer disagreement caused him to query his subordinates in the spring of 1945. Only then did he learn of the clear superiority in armor, armament, and even maneuverability of the heavy German models.

In early 1945, apparently as a result of the large-scale German armored attacks during the Battle of the Bulge, the US Amy finally allowed a few heavy tanks of the T20 series to be sent to Europe for combat testing. The army's Ordnance Department had developed the T20 series in 1943, but considerations of doctrine, shippingp and mass production had prevented its use in battle until the closing days of the war.

The T-34 Multiple Rocket Launcher, mounted on M4A3 tanks, fired 4.5-inch rockets. The M4A3E2 was a Sherman medium tank to which more armor had been added. Only a few of this model reached the European Theater of Operations before the end of 1944. It was intended as a stop-gap until the heavier Pershing tank could be put into production. The M4A3(E8) "Easy Eight" tank did not enter service until late in the war. The M4-A3HVSS Sherman tank was one of the most widely produced in its time. Its weapon systems consist of a 105-millimeter cannon, and two .30-caliber machine-guns.

Great Britain also used the Sherman during the latter half of World War II, but was concerned by the limited penetrating power of the M41s 75-mm, medium-velocity main gun. Dissatisfied with the weapon, but not constrained by the American War Department, the British modified a number of their Shermans. After considerable discussions with the Americans, the British finally modified some of the Shermans they received. The British version of the Sherman, called the "Firefly," included the third-generation British antitank gun, the seventeen pounder (77-mm). This gun fired a far larger round, and its long bore and higher velocity gave it much greaber capability against German armor. Mounting this gun required cutting out the rear wall of the Sherman's turret and adding an armored box, as well as a new hatch for the loader. To carry a useful number of the big 17-pounder rounds, they also removed the bow machine gun and gunner. Almost as fast as a standard Sherman, it was not quite as good as a German PzKwIVH but at least the gap had been narrowed.

Of the 3,202 medium Sherman tanks in the United States in 1950, 1,326 were unserviceable. Building a tank requires a long lead time. Thousands of parts must be manufactured and assembled. Specialized tools and dies are required, as are skilled engineers and workers. Because of the extensive time required to retool and reenergize American tank production during the Korean War, more troops were using the World War II vintage Sherman tank than the newer M-46 "Patton" as late as October 1952.



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Page last modified: 04-05-2019 18:13:39 ZULU