T30 heavy tank

Heavy Tank T30
Type	Heavy tank
Place of origin	United States
Service history
In service	Trials only
Used by	United States of America
Production history
Designed	Pilot models started in April 1945
Produced	1947
Variants	T30E1, T30E2
Specifications
Weight	142,600 lb (64.7 t)
Length	429 in (10.9 m) gun forward
Width	3.80 m (12 ft 6 in) (T30)
Height	3.20 m (10 ft 6 in)
Crew	6 (Commander, Gunner, Driver, Radio Operator, 2 x loader)
Armor	Hull 4 in (100 mm) maximum Turret 11 in (280 mm) maximum
Main armament	155mm L/40 T7 rifled gun (T30) (34 rounds) 155 mm L/40 T7E1 gun (T30E1)
Secondary armament	2x .50 cal (12.7 mm) M2 HB machine gun and .30 cal (7.62 mm) M1919A4 machine gun
Engine	Continental AV1790-3 air-cooled 704 hp (525 kW) net at 2,800 rpm
Power/weight	10 hp/tonne
Suspension	torsion-bar
Operational range	approx 100 miles (160 km)
Speed	22 mph (35 km/h) on roads

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 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.

Plans for four pilot heavy tanks were put forward in 1944; two T29 with a 105 mm gun and two T30 with a 155 mm gun. The T30 pilot models were started in April 1945 and were delivered in 1947. Apart from modifications to fit the different engine, the chassis was the same as the T29. The 155 mm (6.1 in) gun fired two-piece (shell and charge) ammunition. The loader was assisted by a spring rammer. The T30 was fitted with one of the largest guns ever used on an American tank. The notably high, rounded edge, turret was needed to accommodate the standing loader and large gun mount. Even then the gun could only be loaded at limited elevations. It could carry a mixed assortment of 34 AP (Armored Piercing) or HE (high-explosive) rounds.

One pilot model -designated T30E1 - had an automatic system added to load the ammunition. This brought the gun breech into position, loaded the round and then returned the gun to the initial angle. An additional hatch at the back of the turret was added for the automatic ejection of the empty shell casings. The weight of the T30 shell was 43 kg (95 lb) and the charge 18 kg (40 lb), a total of 61 kg (134 lb) for the whole round, which made it difficult to handle and gave it a rate of fire of only two rounds per minute when manually loaded. Another variant of the tank was the T30E2.

The surviving examples are in Fort Benning, Georgia. One surviving T30 is at the Detroit Arsenal in Warren, MI. Another T30 is located at Fort Jackson, South Carolina.