M6 was an American heavy tank that was designed in 1940 with a mass of more than 57 tons and with a 76 mm gun and a coaxial 37 mm gun. The tank was not successful despite its power, especially for handling needs through the ‘Atlantic on board merchant ships. During thewas the prime improved handling of ‘ .
In the spring of 1940, the U.S.Department began a program for the construction of a heavy tank, firepower comparable to what has already been achieved in previous years in Europe. On 20 May 1940 the Office of the Chief of the U.S. Army sent Ordnace Department’s request for the development of a heavy tank alongside the M2A1 medium tank then in service. Which proved inadequate for the needs of the war chariot M2A1 was never used in action, and was replaced on the construction lines from ‘M3 General Lee. Following this request the Ordnace Department started the work for the project definition.
The first draft included a chariot multi-head weighing about 50 tons. The main turret would have been armed with a piece T6 at low speed of 75 mm, while the other two towers were armed, one with a 37 mm cannon, and the other with a 20 mm cannon both supported by a coaxial machine gun 7.62 mm. In front and behind the hull there would be an additional four 7.62 mm machine guns on media sphere. The project was approved on 11 June 1940, the designation HeavyT1. The construction of the prototypes was entrusted to the firm Baldwin Locomotive Works.
As he was proceeding to the preparations for the construction of prototypes, and the choice was made of the engine and mechanical solutions to be adopted, rose problems related to the solution chosen for the equipment. The solution multi-head had been abandoned in Europe for some time, due to problems related to the complex management of these means, also equipped with a crew too numerous. In October 1940, American technicians of theDepartment had come to the same choice of European colleagues. The armament of the project was greatly simplified T1, the secondary turrets were all canceled and there was only one main.
The crew consisted of six men: commander, gunner and assistant gunner, located in the tower, one involved in the management of ammunition placed in the hull, the driver and assistant driver seated at the front of the hull. The commander was in charge of operating the machine gun 12.7 mm anti-aircraft positioned on the sky tower. The propulsion was based on a radial engine aeronautical Wright G-200 (Model 791C0GC1) Cyclone 9, 9-cylinder air-cooled engine capacity of 29 873 cc, dispensing 825 HP at 2,300 revolutions / minute. The choice of the engine was carried out by the Society of Automotive Engineers after a thorough analysis of the needs of the power of the new tank. The fuel capacity was equal to 1,812 liters, while consumption was 1.132 liters per 100 km.
The choices for armor and transmission generated a lot of discussion. Failing to make a final choice, the selection was left to the practical experimentation. At Baldwin were ordered prototypes with transmission systems and hull structure different. They were originally planned three prototypes with electric transmission, two with torque converter and two others with hydraulic transmission. Some of these were fitted with armor plates welded to other plates fused. The suspension was ensured at each side, on all design, four carts on two wheels and suspension mainspring horizontal. The security side of the train rolling was entrusted to a wide scudatura apron. The main armament was based on an M7 76.2 mm cannon with 75 rounds. The secondary armament concerned a coaxial M6 37 mm cannon with 202 rounds. In the front part of the hull in station operated shielded from the server of the driver, there were two machine guns Browning M1919A4 7.62mm, with a total of 5,500 hits and 2 machine guns Browning M2HB 12.7 mm with a total of 6,900 hits. They were placed in as many slits at the front end of the front scudatura. Such weapons, with the aid of electric actuators, were handled by the driver. On the sky tower was installed a Browning M2HB 12.7 mm machine gun for anti-aircraft fire. The performance predicted a maximum speed of 35 km / h with a range of 160 km on the road, the ability to ford was equal to 1.20 m, the maximum surmountable trench was 3.35 m, while the maximum surmountable obstacle was of 0.91 m.
In 1941, Baldwin began the construction of two prototypes equipped with hydraulic transmission. The one with armor plates fused kept the name T1, while the plate was welded designated T1E4. The T1E1 was the prototype hull melted and electrical transmission, while those with torque converter were designated T1E2, while those with torque converter and welded armor became T1E3.
The construction of the prototypes T1 and T1E4 was never completed because of the occurrence of a number of technical problems. Baldwin also built eight T1E2 that, in December 1942, the war had begun, were reclassified M6. At the end of 1942 were delivered twelve o’clock copies of the version of the M5A1 and M6A2 winds. The armor of these tanks was evaluated positively Ordnance Department, which also considered good autonomy. The only defect was the maximum speed, judged soon enough. At the beginning of 1943, the Ordnance Department, along Armored, considered the issue of a first order for the supply of 115 wagons, while requiring funds to build a series of 1,000 units.
Unfortunately, according to the technical Armored, the weight of 57 tons and dimensions of the vehicle, he would have a negative impact on ship handling of the wagon. In addition, the Armored urged the Ordnance Depertment to create new versions of the medium tank, while simultaneously developing new heavy tanks. To unlock the program groped M6, the Ordnance Department, in the course of 1943, Baldwin recommended that the design of a heavy-duty version with 77 tons and 190 mm of frontal armor, designated M6A2E1. The prototype of this tank would have to be made for converting a series of M6A2. The idea was not well received Armored Corps, who believed that the overweight have a marked influence on the mobility of the vehicle, reducing the possibilities of employment. The Ordnance Department estimated long the adoption of a more powerful armament. It was estimated to equip a wagon prototype of a 90 mm gun T7, but then it was decided to modify a T1E1 providing it with a turret armed with a T5E1 105 mm piece. This transformation was designated M6A2E1-1.
This operation was stopped in August 1944 by the decisive intervention of General. The Baldwin Locomotive Works was pressing to get to the series production of the vehicle, stating that in the event of immediate order, the first model series would be delivered on 15 November 1944. General stopped, however, any further investment on the vehicle, judging it a waste of time and resources to svafore the latest versions of the medium tank. On 14 December 1944, the M6 wagon was officially declared obsolete. Various prototypes appeared in propaganda films and then they were sent for demolition.
Today, a wagon version of the M6A2 can be admired at the United States Army Ordnace Museum in Aberdeen, Maryland.
T1: prototype with armor plates fused and hydraulic transmission. Not completed because of the occurrence of technical problems.
T1E1: a prototype hull melted and electrical transmission.
T1E2: two prototypes with torque converter.
T1E3: two prototypes with torque converter and welded armor.
T1E4: a prototype with armor plates welded and hydraulic transmission. Not completed because of the occurrence of technical problems.
M6: eight copies of pre-series, already designated T1E2.
M6A1: version made in twelve specimens (such as T1E3)
M6A2: version made twenty specimens (such as the T1E1)
M6A2E1: Draft Version heavy 77 tons and with 190 mm of frontal armor. Unrealized.
M6A2E1-1: a prototype proceeds to the processing of a T1E1 with turret armed with a piece T5E1 105 mm.
U.S. military vehicles of