31 Trial and research tanks of the United States

The Chrysler TV-8 was a tank design project by Chrysler in the 1950s. The tank was intended to be a medium tank capable of land and amphibious warfare. The design was never produced.

The CLB 75 Tank was a U.S.-produced, prototype armoured fighting vehicle built by C. L. Best's Traction Company of San Leandro, California. Best was a rival of the Holt Manufacturing Company in producing caterpillar tracked vehicles. Among Best's products was the CLB 75 hp (56 kW) 'Tracklayer' The tank was developed by putting an armoured hull over a CLB 75 sometime between late 1916 and early 1917.

The Ford 3-Ton M1918 was one of the first tank designs by the U.S. It was a small two-man, one-gun tank. It was armed with a M1919 Browning machine gun and could reach a maximum speed of 8 mph (13 km/h). The 3-Ton had a 17-US-gallon (64 l) tank that gave it a maximum range of 34 miles (55 km).

The Holt Gas-Electric Tank was the first prototype tank built in the United States in a collaboration between the Holt Manufacturing Company and the General Electric Company. The tank, built during 1917-1918, was the only one of its kind built, as testing proved it lacked the agility and maneuverability required. The crew number is often given as six, on the assumption there would be two machine gunners, a gunner and loader for the main gun, a driver and a commander.

Killen-Strait was an American engineering company.

The United Defense M8 Armored Gun System was an American light tank that was intended to replace the M551A1 Sheridan in the 82nd Airborne Division, as well as being expected to replace TOW-equipped Humvees in the 2nd Armored Cavalry Regiment. The M8 project was eventually canceled in 1997. Its role in the 2nd ACR was eventually taken by the M1128 Mobile Gun System, but a modernized version of the vehicle is in trials with the US Army once more.

The Medium Tank T20, Medium Tank T22 and Medium Tank T23 were medium tank designs developed by the United States during the Second World War, to be the successor to the M4 Sherman.

The MBT-70 was an American–West German joint project to develop a new main battle tank during the 1960s.

The Medium Tank M7, initially Light Tank T7, was an American tank, originally conceived as an up-gunned replacement for the Light Tank M3/M5 ("Stuart"). The project developed to mount the same 75mm armament as the M4 Sherman while retaining the light weight and maneuverability of the M3 Stuart; however, during development the weight of the prototype surpassed the US Army's standard for light tanks and crossed into the medium tank category and was renamed. The M7 had significantly less armor than the M4 Sherman, no greater firepower, and held only a slight advantage in top speed. For these reasons, and because the M4 was already battle-tested and in full production, the M7 was cancelled in 1943.

The Medium Tank M1921 was a medium tank built in the United States in the inter-war period. In design, it was similar to earlier WW1 era tanks. United States Army engineers worked on the design of the tank, with some influence from British designs of the period, and from the earlier war experience. One example was produced. The tank was an early example of a turreted US tank, less usual at the time, with the turret housing the main gun, with the tank also possessing two machine guns for defence.

The Medium Tank M1922 was an inter-war period medium tank built in the United States. It was largely a variant of the Medium Tank M1921, with some changes to use the same track suspension system that had been developed for the Medium Mark D.

The Ripsaw is a series of developmental unmanned ground combat vehicles designed by Howe & Howe Technologies for evaluation by the United States Army.

The Skeleton Tank also known as the Spider Tank was an experimental prototype tank built in 1918 by the Pioneer Tractor Company, Winona, Minnesota for $15,000. The Prototype was ready for trials by October 1918. Designed with several innovative features, some of which were controversial at the time, the Skeleton Tank project did not proceed beyond the single prototype tank.

The Steam Tank (Tracked) was an early U.S. tank design of 1918 imitating the design of the British Mark IV tank but powered by steam.

The Steam Wheel Tank was a U.S.-produced, prototype armoured fighting vehicle built by the Holt Manufacturing Company. Developed sometime between late 1916 and early 1917, it was the third tank to be designed in the U.S. The prototype was completed in February 1918 and was evaluated between March and May 1918 at Aberdeen Proving Ground. It performed poorly and was not developed further.

The Light Tank, T1 was a United States Army light tank of the late 1920s and early 1930s that was only built in prototype form. The tank was an Army design built by James Cunningham, Son and Company. Introduced in 1927, it was developed up through 1932 as a series of modified versions. The tank was never mass-produced, nor was it ever used in combat.

The T2 Medium Tank was an American design that replaced three prototype medium tank designs started in the 1920s for an experiment conducted by the United States Army. The T2 tank never saw combat nor left prototype stages and due to lack of funds was not mass-produced with only one built in 1930 by Rock Island Arsenal. Its legacy, however, was the M2 light tank, developed into the M2 medium, and onto the M3 Lee and M4 Sherman medium tanks.

T7 Combat Car was a prototype United States light tank design of the interwar period. It could run on rubber-tired wheels on roads or mount tracks for cross-country use. Although adequate in some areas, it lacked armament compared to contemporary vehicles and the project was cancelled after only one was built.

The Assault Tank T14 was a joint project between the United States and the United Kingdom with the goal being to produce a universal infantry tank.

The Medium Tank T20, Medium Tank T22 and Medium Tank T23 were medium tank designs developed by the United States during the Second World War, to be the successor to the M4 Sherman.

The T28 Super Heavy Tank was an American heavily armored tank/self-propelled gun designed for the United States Army during World War II. It was originally designed to break through German defenses of the Siegfried Line, and was later considered as a possible participant in the planned invasion of the Japanese mainland.

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 opportunities for applying engineering concepts to artillery and automotive components.

The Heavy Tank T30 was a World War II American tank project developed to counter new German tanks, such as Tiger I, Tiger II, and tank destroyers, such as the Jagdtiger, or Soviet heavy tanks, such as IS-1 or IS-2. The T30 was designed at the same time as the T29 Heavy Tank.

The T32 Heavy Tank was a heavy tank project started by the United States Army to create an appropriate successor to the M4A3E2 Sherman "Jumbo". The US Ordnance board managed the production of four prototypes, the main goal being to have the new tank share many common parts with the M26 Pershing.

The T54 was a series of prototype American tanks of the 1950s with three different turrets, all armed with a 105 mm gun, mounted on the M48 Patton chassis. The T54 had a conventional turret with an autoloader with 3 shells, the T54E1 had an oscillating design with an autoloader, and the T54E2 had a conventional turret with a human loader. The turret on T54E1 was similar to that of the T69 in its oscillating design and in that it held a crew of three and a nine-round drum autoloader under the gun. The T54E1 was abandoned in 1956 and in 1957 the entire project was cancelled in favor of the T95 Medium Tank.

The T57 heavy tank was an experimental heavy tank developed by the American military during the Cold War era as a further development of the M103 heavy tank. Featuring heavy armour and a long range 120 mm rifled gun, the T57 was supposed to serve as a replacement to the M103 in service with American heavy tank units in Europe. Armor on the hull front was to range between 137-203mm in thickness and the turret was to be 152mm at maximum on all sides. Like the French AMX 50 project, it was to feature an oscillating turret and was also to receive a 153mm gun. Experiments were also conducted to look into the possibility of the tank being able to mount a 203mm gun, but this was soon found to be infeasible. When multiple problems were discovered in the turret oscillation system on account of the excess weight of the heavily armored turret and the gun, the project was dropped.

The T69 was a prototype American medium tank with an oscillating turret mounting a 90mm cannon with an eight-round drum autoloader. It held a crew of three. Developed on the basis of the T42 experimental medium tank in mid-50s, the vehicle never entered mass production.

T92 Light Tank, or 76-mm Gun Tank, T92, was an American light tank developed in the 1950s by Aircraft Armaments. At 18.5 tonnes, 5m length, it was designed as an airborne/airdropped replacement for the 5.1 tonnes heavier M41 Walker Bulldog. The T92 was never accepted into service.

The T95 was an American prototype medium tank developed from 1955 to 1959. These tanks used many advanced or unusual features, such as siliceous-cored armor, a new transmission, and the OPTAR fire-control system. The OPTAR incorporated an electro-optical rangefinder and was mounted on the right side of the turret, and was used in conjunction with the APFSDS-firing 90 mm T208 smoothbore gun, which had a rigid mount without a recoil system. In addition, although the tanks were designed with a torsion beam suspension, a hydropneumatic suspension was fitted, and one of the tanks was fitted with a Solar Saturn gas turbine for demonstration purposes.