T29 Heavy Tank  The Heavy Tank T29 and Heavy Tank T34 were American heavy tanks projects started in March 1944 to counter the appearance of the German Tiger II heavy tank. The T26E3 medium tank (which entered service as the M26 Pershing), weighed around 45 short tons, but was not considered heavily enough armed or armored to counter the Tiger II, which weighed closer to . 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 T29 was based upon a lengthened version of the T26E3 chassis and featured heavier armor, an upgraded Ford GAC engine producing about gross, net, more comfortable controls for the driver, and a massive new turret incorporating the high-velocity 105 mm gun T5. It weighed approximately unstowed and combat loaded. Its maximum armor thickness was 279 mm compared to 180 mm on the German Tiger II while its 105 mm gun was 7.06 m long (66 calibres, 105L67) compared to the 6.29 m of the Tiger II's 88 mm. (71 calibers long, 88/L71) Other trial models had Allison V1710 V12 engines. The T29 featured a coincidence rangefinder projecting from both sides of the turret, distinctively resembling "ears". The procurement of 1,200 T29s was proposed on 1 March 1945, and revised to 1,152 on 12 April 1945, but by shortly after the end of World War II, only one T29 had been produced, with a second partially completed. In August 1945, the order was cancelled entirely, and it was intended to procure ten T29s for postwar testing. This number was later reduced to eight in July 1947. Developed at the same time and closely related to the T29, the T30 Heavy Tank was virtually identical, but was mounted with the 155 mm gun T7, featured a more powerful engine, and had an additional crew member to help load the heavy ammunition for the gun. Two vehicles were produced. The final variation of the T29 concept, the heavy tank T34, mounted a 120 mm gun based upon the then-current 120mm M1 anti-aircraft gun to further increase the armor penetration capability of the T29. This gun was designated as the 120 mm T53, which could achieve a maximum rate of fire of 5 rounds per minute with two loaders. With solid shot weighing , it had a muzzle velocity of .