M1 Abrams 105 Free 3D model

The M1 Abrams is a third-generation American main battle tank designed by Chrysler Defense (now General Dynamics Land Systems) and named for General Creighton Abrams. Conceived for modern armored ground warfare, it is one of the heaviest tanks in service at nearly 73.6 short tons (66.8 metric tons). It introduced several modern technologies to United States armored forces, including a multifuel turbine engine, sophisticated Chobham composite armor, a computer fire control system, separate ammunition storage in a blowout compartment, and NBC protection for crew safety. Initial models of the M1 were armed with a 105 mm M68 gun, while later variants feature a license-produced Rheinmetall 120 mm L/44 designated M256.

The M1 Abrams was developed from the failed joint American-West German MBT-70 project that intended to replace the obsolete M60 tank. There are three main operational Abrams versions: the M1, M1A1, and M1A2, with each new iteration seeing improvements in armament, protection, and electronics.

The Abrams was to be replaced in U.S. Army service by the XM1202 Mounted Combat System, but because that project was canceled, the Army has opted to continue maintaining and operating the M1 series for the foreseeable future by upgrading optics, armor, and firepower.

The M1 Abrams entered service in 1980 and serves as the main battle tank of the United States Army and formerly of the United States Marine Corps (USMC) until the decommissioning of all USMC tank battalions in 2021. The export modification is used by the armed forces of Egypt, Kuwait, Saudi Arabia, Australia, Poland and Iraq. The Abrams was first used in combat by the U.S. in the Gulf War. It was later deployed by the U.S. in the War in Afghanistan and the Iraq War, as well as by Iraq in the war against the Islamic State, Saudi Arabia in the Yemeni Civil War, and Ukraine in the Russian invasion of Ukraine.

Through the 1960s, the U.S. Army and Bundeswehr had collaborated on a single design that would replace both the M60 tank and the Leopard 1. The overall goal was to have a single new design with improved firepower to handle new Soviet tanks like the T-62, while providing improved protection against the T-62's new 115 mm smoothbore gun and especially high-explosive anti-tank (HEAT) rounds.[citation needed]

The resulting design, the MBT-70, incorporated new technologies across the board. A hydropneumatic suspension provided improved cross-country ride quality and also allowed the entire tank to be raised or lowered by the driver. The newer 1,500 hp (1,100 kW) Avco-Lycoming AGT1500 engine powered the designs which could both reach 43 miles per hour (69 km/h). The American version used a 152 mm gun whose primary long-range weapon was the Shillelagh missile.

While the design was highly capable, its weight continued to grow, as did its budget. By 1969, the unit cost stood at five times the original estimates, causing the Department of Defense to suspend the program.[12] Development of the tank continued on an austere basis until January 1970, when the DoD and Germany ended their partnership.[13]

The U.S. Army began work on an austere version of the MBT-70, named XM803. The Army's changes were insufficient to allay concerns about the tank's cost.[14] Congress canceled the XM803 in December 1971 but permitted the Army to reallocate remaining funds to develop a new main battle tank.

The Army began the XM815 project in January 1972. The Main Battle Tank Task Force (MBTTF) was established under Major General William Desobry. The task force prepared design studies with the technical support of Tank-automotive and Armaments Command (TACOM).[16] TACOM began examining specific goals. To this end, a new design basis emerged in February 1973. It had to defeat any hit from a Soviet gun within 800 m (2,600 ft) and 30 degrees to either side. The tank would be armed with the 105 mm M68 gun, a licensed version of the Royal Ordnance L7, and a 20 mm version of the M242 Bushmaster.[17] The Army later deleted the latter from the design, seeing it as superfluous.

In spring 1972, Desobry was briefed by the British on their own newly developed Burlington armor from the British Army's labs. The armor performed exceptionally against shaped charges such as HEAT rounds. In September, Desobry convinced the Army to incorporate the new armor. To take full advantage of Burlington, also known as Chobham, the new tank would have to have armor around two feet thick (for comparison, the armor on the M60 is around four inches thick). General Creighton Abrams set the weight of the new tank at 58 short tons (53 t). The original goal of keeping weight under 50 short tons (45 t) was abandoned.

At the time, the Pentagon's procurement system was beset with problems being caused by the desire to have the best possible design. This often resulted in programs being canceled due to cost overruns, leaving the forces with outdated systems, as was the case with the MBT-70. There was a strong movement within the Army to get a new design within budget to prevent the MBT-70 experience from repeating itself. For the new design, the Army set the design-to-unit cost at no more than $507,790 (equivalent to $3,699,000 in 2023).

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