M6 heavy tank
   HOME

TheInfoList



OR:

The Heavy Tank M6 was an American
heavy tank Heavy tank is a term used to define a class of tanks produced from World War I through the end of the Cold War. These tanks generally sacrificed mobility and maneuverability for better armour protection and equal or greater firepower than tanks ...
designed during
World War II World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the vast majority of the world's countries—including all of the great powers—forming two opposin ...
. The tank was produced in small numbers and never saw combat.


Development

Because of limited budgets for tank development in the interwar years, at the outbreak of World War II the
United States Army The United States Army (USA) is the land service branch of the United States Armed Forces. It is one of the eight U.S. uniformed services, and is designated as the Army of the United States in the U.S. Constitution.Article II, section 2, cla ...
possessed few tanks, though it had been keeping track of the use of tanks in Europe and Asia. Successful employment of armored units in 1939–40, mostly by the
Germans , native_name_lang = de , region1 = , pop1 = 72,650,269 , region2 = , pop2 = 534,000 , region3 = , pop3 = 157,000 3,322,405 , region4 = , pop4 = ...
, gave momentum to a number of US tank programs, including a heavy tank. The United States possessed a massive industrial infrastructure and large numbers of engineers that would allow for mass production of tanks. Following the Chief of Infantry recommendation from May 1940, the US Army Ordnance Corps started to work on a 50-ton heavy tank design. The project was approved in June and the vehicle received the designation Heavy Tank T1. Initially, a multi- turreted design was proposed, with two main turrets each armed with a low-velocity T6 75 mm (2.95 inch) gun, a secondary turret with a 37 mm gun and a coaxial .30 caliber (7.62 mm)
machine gun A machine gun is a fully automatic, rifled autoloading firearm designed for sustained direct fire with rifle cartridges. Other automatic firearms such as automatic shotguns and automatic rifles (including assault rifles and battle rifles) a ...
, and another secondary turret with a 20 mm gun and a coaxial .30 caliber machine gun. Four .30 caliber machine guns were to be installed in ball mounts, two in the
glacis A glacis (; ) in military engineering is an artificial slope as part of a medieval castle or in bastion fort, early modern fortresses. They may be constructed of earth as a temporary structure or of stone in more permanent structure. More genera ...
(front) plate and two in the rear corners of the hull. The design was somewhat similar in concept to multi-turreted breakthrough tanks developed in Europe in the 1920s and throughout the 1930s, such as the 1925 British
Vickers A1E1 Independent The Independent A1E1 is a multi- turreted tank that was designed by the British armaments manufacturer Vickers between the First and Second World Wars. Although it only ever reached the prototype stage and only a single example was built, it i ...
or the Soviet
T-35 The T-35 was a Soviet Union, Soviet multi-gun turret, turreted heavy tank of the interwar period and early Second World War that saw limited production and service with the Red Army. Often called a land battleship, it was the only five-turreted ...
of the early 1930s, albeit on a much more powerful scale: the older tank designs were typically armed with a single light or medium-caliber main gun and multiple machine guns, and had armor only sufficient to protect from small arms fire. Later in the decade, however, European tank developers switched to single-turret designs. By October, the US developers reached the same conclusion as their European counterparts. The armament was changed to a single vertically stabilized 3-inch (76.2 mm) gun and a coaxial 37 mm gun in a single three-man turret with both manual and electric traverse. The turret had a commander's cupola identical to that of the M3 Medium Tank. Additional armament consisted of two .50 caliber machine guns in a bow mount (operated by the assistant driver), two .30 caliber machine guns in the front plate (fired electrically by the driver), one .30 caliber in the commander's cupola and one .50 caliber in a rotor mount for anti-aircraft use in the right rear of the turret roof (operated by the loader). The crew consisted of commander (seated in the turret left), gunner to the right of the gun, gun loader (turret), driver and assistant driver in the front left and right of the hull respectively, and another crewman in the hull to pass ammunition to the turret. One of the main challenges was developing a powerpack for such a heavy vehicle. The Wright G-200 air-cooled
radial Radial is a geometric term of location which may refer to: Mathematics and Direction * Vector (geometric), a line * Radius, adjective form of * Radial distance, a directional coordinate in a polar coordinate system * Radial set * A bearing f ...
gasoline engine A petrol engine (gasoline engine in American English) is an internal combustion engine designed to run on petrol (gasoline). Petrol engines can often be adapted to also run on fuels such as liquefied petroleum gas and ethanol blends (such as ''E ...
was selected by a committee formed by the
Society of Automotive Engineers SAE International, formerly named the Society of Automotive Engineers, is a United States-based, globally active professional association and standards developing organization for engineering professionals in various industries. SAE Internatio ...
, but no suitable transmission was available. The committee recommended developing a hydramatic transmission, while a possibility of using a
torque converter A torque converter is a type of fluid coupling that transfers rotating power from a prime mover, like an internal combustion engine, to a rotating driven load. In a vehicle with an automatic transmission, the torque converter connects the power ...
or an electric transmission was also to be checked. The project was first publicly disclosed in August 1940 when the Army awarded
Baldwin Locomotive Works The Baldwin Locomotive Works (BLW) was an American manufacturer of railroad locomotives from 1825 to 1951. Originally located in Philadelphia, it moved to nearby Eddystone, Pennsylvania, in the early 20th century. The company was for decades t ...
in Pennsylvania a $5.7 million contract for the production of 50 tanks. The Army envisioned building 500 of this type. The first T1E1 was delivered to the Army in December 1941. From 1941 to 1942, three prototypes were built: one with electric transmission and two with torque converter transmission. Variants with hydramatic transmission were never completed. The prototypes also differed in hull assembly method: one had a welded hull and two had cast hulls. On 26 May 1942, two variants with torque converter transmission were standardized as M6 (cast hull) and M6A1 (welded hull). Standardization of the electric transmission equipped T1E1 as the M6A2 was never approved, but the manufacturing of the vehicle was nevertheless recommended. It was proposed by the Ordnance Corps that 115 T1E1s would be built for the US Army for "extended service tests", between that and Services of Supply instruction to increase production with the balance going to aid US allies, this would mean 50 M6s and 65 M6A1s built for the British. Production started in December 1942. Some minor changes were introduced in the production vehicles: the cupola was replaced by a double-door hatch with a ring mount, while the machine gun in a rotor mount and the left front machine gun were removed. However, by the time the M6 was ready for production, the Armored Corps had lost interest in the project. The advantages the M6 offered over medium tanks – its much thicker armor and slightly more powerful gun – were offset partly by the shortcomings of the design – such as very high silhouette, awkward internal layout and reliability problems – and partly by logistical concerns due to its weight. In early 1942, the Ordnance Department set a production target of 250 a month, with Fisher as a second contractor to meet a planned expansion in the size of the army.Chamberlain & Ellis, page 155 However, by September, the focus had changed, with tank production scaled back and more aircraft for the USAAF. Under this new "Army Supply Program", the M6 production was cut from 5,000 to a little over 100. By the end of 1942, the Armored Corps were of the opinion that the new
M4 Sherman } The M4 Sherman, officially Medium Tank, M4, was the most widely used medium tank by the United States and Western Allies in World War II. The M4 Sherman proved to be reliable, relatively cheap to produce, and available in great numbers. It ...
gave adequate solution for the present and the near future, while being reliable, cheap and much easier to transport and they had no need for a heavy tank. In 1943, the production target was reduced again, down to 40, being an economic cut-off. Production M6 and pilot M6A1 examples were evaluated at Fort Knox in the early part of 1943. The reports were critical of the awkward and inefficient crew stations, and the superfluous 37mm gun. However, in October, the tank had performed well enough at
Aberdeen Proving Ground Aberdeen Proving Ground (APG) (sometimes erroneously called Aberdeen Proving ''Grounds'') is a U.S. Army facility located adjacent to Aberdeen, Harford County, Maryland, United States. More than 7,500 civilians and 5,000 military personnel work at ...
to proceed. The Ordnance Corps had expected the 75 mm gun to be lacking, and the T1E1 prototype was tested with a T7 90 mm gun and was found to be a satisfactory gun platform, although the poor turret layout was again noted. By this point, the M6 had been cancelled. In August 1944, the Ordnance Corps recommended modifying the T1E1s to build 15 specially armored and armed tanks to meet a need for attacking heavily fortified areas. These 77-ton vehicles – designated M6A2E1 – with thicker (equivalent to vertical protection) glacis armor and a turret developed for the
T29 Heavy Tank The Heavy Tank T29 was an American heavy tank project started in March 1944 to counter the appearance of the German Tiger II heavy tank. The T29 was not ready in time for the war in Europe, but it did provide post-war engineers with opportuniti ...
, armed with a T5E1 105 mm gun but no increase in engine power. Ordnance believed they could be delivered by November. The proposal was put to the supreme commander in Europe
General Eisenhower Dwight David "Ike" Eisenhower (born David Dwight Eisenhower; ; October 14, 1890 – March 28, 1969) was an American military officer and statesman who served as the 34th president of the United States from 1953 to 1961. During World War II, ...
, who rejected them as impracticable. Two tanks were used to test the T29 turret and gun, but their armor was not modified. On 14 December 1944, the M6 was declared obsolete. Only 40 had been produced and they never left US soil. Several toured the United States for propaganda purposes, where they gave performance displays (such as car crushing) at
War Bond War bonds (sometimes referred to as Victory bonds, particularly in propaganda) are debt securities issued by a government to finance military operations and other expenditure in times of war without raising taxes to an unpopular level. They are ...
drives and the like. All were eventually scrapped except for a single T1E1, which was put on display at the
United States Army Ordnance Museum The United States Army Ordnance Training Support Facility (formerly known as the U.S. Army Ordnance Training and Heritage Center and U.S. Army Ordnance Museum) artifacts are used to train and educate logistic soldiers. It re-located to Fort Lee ( ...
,
Aberdeen, Maryland Aberdeen is a city located in Harford County, Maryland, United States, northeast of Baltimore. The population was 16,254 at the 2020 United States Census. Aberdeen is the largest municipality in Harford County. Aberdeen is part of the Baltimor ...
. The British used the suspension of the M6 in the first of their two A33 Heavy Assault Tank "Excelsior" prototypes.


Variants

*T1 – Cast hull, hydramatic transmission. Never built. *T1E1 – Cast hull,
General Electric General Electric Company (GE) is an American multinational conglomerate founded in 1892, and incorporated in New York state and headquartered in Boston. The company operated in sectors including healthcare, aviation, power, renewable energ ...
electrical transmission.Hunnicutt p37 Standardization proposed as M6A2 but not accepted. 20 units built. *T1E2 / M6 – Cast hull, torque converter transmission. 8 units built. *T1E3 / M6A1 – Welded hull, cast turret,
torque converter A torque converter is a type of fluid coupling that transfers rotating power from a prime mover, like an internal combustion engine, to a rotating driven load. In a vehicle with an automatic transmission, the torque converter connects the power ...
transmission. 12 units built. *T1E4 – Welded hull, hydramatic transmission. Four GM engines. Cancelled 1942. Never built. *M6A2E1 – Uparmored T1E1 fitted with a new turret with a T5E1 105 mm gun. Used for testing T29 heavy tank project armament system. Project cancelled at 22 August 1944. 2 units built.


See also

*
List of U.S. military vehicles by supply catalog designation This is the Group G series List of the United States military vehicles by (Ordnance) supply catalog designation, — ''one'' of the alpha-numeric "Standard Nomenclature Lists" (SNL) that were part of the overall List of the United States Army w ...
*
List of U.S. military vehicles by model number The following is a (partial) listing of vehicle model numbers or M-numbers assigned by the United States Army. Some of these designations are also used by other agencies, services, and nationalities, although these various end users usually assig ...
* TOG II* – British superheavy prototype tank for trench warfare * T29 – late-war prototype heavy tank; early version turret and gun was tested on M6A2E1 variant ;Tanks of comparable role, performance and era *German VK 30.01 (H) – prototype for the
Tiger I The Tiger I () was a German heavy tank of World War II that operated beginning in 1942 in Africa and in the Soviet Union, usually in independent heavy tank battalions. It gave the German Army its first armoured fighting vehicle that mounted ...
*British
Excelsior Excelsior, a Latin comparative word often translated as "ever upward" or "even higher", may refer to: Arts and entertainment Literature and poetry * "Excelsior" (Longfellow), an 1841 poem by Henry Wadsworth Longfellow * ''Excelsior'' (Macedo ...
– prototype heavy tank, two built, did not enter service *British
Churchill Sir Winston Leonard Spencer Churchill (30 November 187424 January 1965) was a British statesman, soldier, and writer who served as Prime Minister of the United Kingdom twice, from 1940 to 1945 during the Second World War, and again from 1 ...
– heavy tank, entered service in 1941 *American-British T14 – prototype heavy tank with similar specifications *Soviet
KV-1 The Kliment Voroshilov (KV) tanks are a series of Soviet heavy tanks named after the Soviet defence commissar and politician Kliment Voroshilov who operated with the Red Army during World War II. The KV tanks were known for their heavy armour pro ...
– heavy tank, entered service in 1939 ;Contemporaries to M6A2E1 variant *German
Tiger II The Tiger II is a German heavy tank of the Second World War. The final official German designation was ''Panzerkampfwagen'' Tiger ''Ausf''. B,''Panzerkampfwagen'' – abbr: ''Pz.'' or ''Pz.Kfw.'' (English: " armoured fighting vehicle"), ''Ausf.' ...
– late-war heavy tank, entered service in 1944 *United States T26E4 "Super Pershing" heavy tank – single prototype
M26 Pershing The M26 Pershing was a heavy tank/medium tank of the United States Army. It was used in the last months of World War II during the Invasion of Germany and extensively during the Korean War. The tank was named after General of the Armies John J. ...
with extra armor and improved gun; fought in Western Europe during 1945 *Soviet IS-2 model 1944 – heavy assault tank, entered service in 1944 *Soviet IS-3 – heavy tank, entered service in 1945, did not see combat *French
ARL 44 The ARL 44 was a French heavy tank, the development of which started just before the end of the Second World War. Only sixty of these tanks were ever completed, from 1949 onwards. The type proved to be unsatisfactory and only entered limited ser ...
– heavy tank, too late to see service


References


Sources

* *R.P. Hunnicutt – ''Firepower: A History of the American Heavy Tank'', 1988 Presidio Press, . *


External links


M6 at World War II vehicles
M6 at AFV database {{DEFAULTSORT:M6 Heavy Tank Heavy tanks of the United States World War II heavy tanks World War II tanks of the United States Abandoned military projects of the United States History of the tank Military vehicles introduced from 1940 to 1944