M46 Patton

M46 Patton
An American M46 Patton tank of the United States Marine Corps, during the Korean War
Type	Medium tank
Place of origin	United States
Service history
In service	1949-1957
Wars	Korean War
Production history
Manufacturer	Detroit Arsenal Tank Plant
Number built	800 + 360 M46A1
Variants	M46A1
Specifications
Weight	48.5 tons (44 metric tons)
Length	27.82 ft (8.48 m)
Width	11.52 ft (3.51 m)
Height	10.43 ft (3.18 m)
Crew	5 (commander, gunner, loader, driver, assistant driver)
Armor	102 mm/4 inches maximum
Main armament	90 mm gun M3A1 70 rounds
Secondary armament	.50 in (12.7 mm) M2 machine gun 2x .30 cal (7.62 mm) M1919A4 machine guns
Engine	Continental AV-1790-5A V12, air-cooled Twin-turbo gasoline engine 810 hp (604 kW)
Power/weight	18.4 hp (13.7 kW) / tonne
Transmission	General Motors CD-850-3 or -4, 2 ranges forward, 1 reverse
Suspension	Torsion bar suspension
Ground clearance	18.82 in (478 mm)
Fuel capacity	878 liters 232 U.S. gallons
Operational range	80 miles (130 km)
Speed	30 mph (48 km/h)

The M46 was an American medium tank designed to replace the M26 Pershing and M4 Sherman. It was one of the U.S Army's principal medium tanks of the early Cold War, with models in service from 1949 to the mid-1950s. It was not widely used by U.S. Cold War allies, being exported only to Belgium, and only in small numbers to train crews on the upcoming M47 Patton.

The M46 was the first tank to be named after General George S. Patton Jr., commander of the U.S. Third Army during World War II and one of the earliest American advocates for the use of tanks in battle.

After World War II, most U.S. Army armored units were equipped with a mix of M4 Sherman and M26 Pershing tanks. Designed initially as a heavy tank, the M26 Pershing tank was reclassified as a medium tank postwar. The M26 was a significant improvement over the M4 Sherman in firepower and protection. Its mobility, however, was deemed unsatisfactory for a medium tank, as it used the same engine as the much lighter M4A3 and was plagued with an unreliable transmission.

Work began in January 1948 on replacing the original power plant with the Continental AV1790-3 engine and Allison CD-850-1 cross-drive transmission. This design was initially called the M26E2, but modifications continued to accumulate; eventually, the Bureau of Ordnance decided that the tank needed its own unique designation. When the rebuild began in November 1949, the upgraded M26 received not only a new power plant and a main gun with a bore evacuator, but a new designation M46. In total, 1,160 M26s were rebuilt: 800 to the M46 standard, 360 to the M46A1.

The only American combat use of the M46 Patton was during the Korean War. On 8 August 1950, the first M46 Patton tanks, belonging to the 6th Tank Battalion, landed in South Korea. The tank proved superior to the much lighter North Korean T-34-85, which were encountered in relatively small numbers. By the end of 1950, 200 M46 Pattons had been fielded, forming about 15% of US tank strength in Korea; the balance of 1,326 tanks shipped to Korea during 1950 were 679 M4A3 Shermans (including the M4A3E8 variant), 309 M26 Pershings, and 138 M24 Chaffee light tanks. Subsequent shipments of M46 and M46A1 Pattons allowed all remaining M26 Pershings to be withdrawn during 1951, and most Sherman equipped units were also reequipped.