Thursday, May 30, 2013

The Mighty M4 Sherman Tank

TankshermanM4.jpgThe M4 Sherman, formally Medium Tank, M4, was the primary tank used by the United States during World War II. Thousands were also distributed to the Allies, including the British Commonwealth and the Soviet Union, via lend-lease. In the United Kingdom, the M4 was named after Union General William Tecumseh Sherman, following the British practice of naming their American-built tanks after famous American Civil War generals. Subsequently, the British name found its way into common use in the U.S.
The Sherman evolved from the Grant and Lee medium tanks, which had an unusual side-sponson mounted 75 mm gun. It retained much of the previous mechanical design, but added the first American main 75 mm gun mounted on a fully traversing turret, with a gyrostabilizer enabling the crew to fire with reasonable accuracy while the tank was on the move. The designers stressed mechanical reliability, ease of production and maintenance, durability, standardization of parts and ammunition in a limited number of variants, and moderate size and weight. These factors made the Sherman superior in some regards to the earlier German light and medium tanks of 1939-41. The Sherman ended up being produced in large numbers and formed the backbone of most offensives by the Western Allies, starting in late 1942.
When the Sherman tank arrived in North Africa in 1942, it was clearly superior to both the Panzer III German main battle tank and the short barreled version of the Panzer IV. Against the 75mm KwK 40 L/43 long barreled Panzer IV the match was about even. For this reason, the US Army believed the Sherman would be completely adequate to win the war, and no pressure was exerted for further tank development. The Sherman proved to be outmatched by the 45 ton Panther tank, and wholly inadequate against the 56 ton Tiger I and later 70 ton Tiger II heavy tanks, suffering high casualties against their heavier armor and more powerful 88 mm L/56 and L/71 cannons. Mobility, mechanical reliability and sheer numbers, supported by growing superiority in supporting fighter-bombers and artillery, helped offset these disadvantages strategically. The relative ease of production allowed huge numbers of the Sherman to be produced. This allowed many divisions, including infantry divisions, their own organic Sherman assets. Some U.S. infantry divisions had more tanks than German panzer divisions did, which was a great advantage for the Americans.
Production of the Sherman was favored by the commander of the Armored Ground Forces, albeit controversially, over the heavier M26 Pershing, which resulted in the latter being deployed too late to play any significant role in the war. In the Pacific Theater, the Sherman was used chiefly against Japanese infantry and fortifications; in its rare encounters with much lighter Japanese tanks with weaker armor and guns, the Sherman's superiority was overwhelming. Almost 50,000 vehicles were produced, and its chassis also served as the basis for numerous other armored vehicles such as tank destroyers, tank retrievers, and self-propelled artillery. Only the Soviet T-34 tank was produced in larger numbers during World War II.
The Sherman would finally give way to post-war tanks developed from the M26. Various original and updated versions of the Sherman would continue to see combat effectively in many later conflicts, including the Korean War, Arab-Israeli Wars, and Indo-Pakistani War (where it was used by both sides) into the late 20th century.

An M4A3E8 76 mm armed Sherman tank made during the Second World War
Type Medium tank
Place of origin  United States
Service history
In service 1942–1955 (USA)
Used by  United States, and many others (see Foreign variants and use)
Wars World War II, Greek Civil War, Arab-Israeli War, Korean War, RevoluciĆ³n Libertadora, Suez Crisis, Indo-Pakistani War of 1965, Six-Day War, Indo-Pakistani War of 1971, Yom Kippur War, 1958 Lebanon crisis, Lebanese Civil War, Cuban Revolution, Nicaraguan Revolution
Production history
Designed 1940
Produced 1941–
Number built 49,234
Weight 66,800 pounds (30.3 tonnes; 29.8 long tons; 33.4 short tons)
Length 19 ft 2 in (5.84 m)
Width 8 ft 7 in (2.62 m)
Height 9 ft (2.74 m)
Crew 5 (Commander, gunner, loader, driver, co-driver)

Armor 76 mm maximum
75 mm M3 L/40 gun (90 rounds)
or 76 mm gun M1 (55 rounds)
.50 cal Browning M2HB machine gun (300 rounds),
2 × .30-06 Browning M1919A4 machine guns (4,750 rounds)
Engine Continental R975 C1, air-cooled, radial, gasoline
400 hp (298 kW) at 2,400 rpm
M4A4 Model - Chrysler A57 Multibank 30 cylinder 21-litre engine. 470 hp at 2,700 rpm.
Power/weight 15.8 hp/tonne
Transmission Spicer manual, synchromesh, 4 forward (plus 1 overdrive) and 1 reverse gear
Suspension Vertical Volute Spring Suspension (VVSS)
120 miles (193 km) at 175 U.S. gal (660 L); 80 octane
Speed 25 to 30 mph (40 to 48 km/h)

M4A4 Cutaway
1 - Lifting ring
2 - Ventilator
3 - Turret hatch
4 - Periscope
5 - Turret hatch race
6 - Turret seat
7 - Gunner's seat
8 - Turret seat
9 - Turret
10 - Air cleaner
11 - Radiator filler cover
12 - Air cleaner manifold
13 - Power unit
14 - Exhaust pipe
15 - Track idler
16 - Single water pump
17 - Radiator
18 - Generator
19 - Rear propeller shaft
20 - Turret basket
21 - slip ring
22 - Front propeller shaft
23 - Suspension bogie
24 - Transmission
25 - Main drive sprocket
26 - Driver's seat
27 - Machine gunner's seat
28 - 75 mm gun
29 - Drivers hatch
30 - M 1919A4 machine gun
M4A4 cutaway.svg