T28 Super Heavy Tank

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For other uses, see T28 or T95 (disambiguation)
T95 Gun Motor Carriage
T-28-1.jpg
At Aberdeen Proving Ground in January 1946[1]
Type Tank Destroyer/ Super Heavy Tank
Place of origin United States
Service history
Used by United States
Production history
Manufacturer Pacific Car and Foundry
Produced 1945
Number built 2
Specifications
Weight 95 short tons (86.2 metric tons)
Length 36 ft 6 in (11.1 m)
Width 14 ft 11 in (4.39 m)
Height 9 ft 4 in (2.84 m)
Crew 4[2][3]

Armor 12 in (305 mm)
Main
armament
105 mm T5E1 gun, with 62 rounds
Secondary
armament
.50 cal (12.7 mm) Browning heavy machine gun, with 660 rounds
Engine Ford GAF V-8 gasoline
500 hp (372 kW)[2]
Power/weight 5.8 hp/tonne
Suspension double tracks, horizontal volute spring
Operational
range
100 miles (160 km)
Speed 8 mph (13 km/h)[3]

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 be used 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 100-ton vehicle was initially designated a heavy tank, it was re-designated as the 105 mm Gun Motor Carriage T95 in 1945, and then renamed in 1946 as the Super Heavy Tank T28.[4]

Name

Initially named Heavy Tank T28 when construction was authorized in 1944, the design did not fit in the usual categories of vehicles leading to reclassification.[5] As it did not have its armament in a revolving turret, Ordnance requested a name change to 105 mm Gun Motor Carriage T95, the change becoming official in March 1945.[6] However, due to its heavy armor and armament — while self-propelled guns in United States service were lightly armored — it was renamed Super Heavy Tank T28 in June 1946 by OCM 37058.[7]

Development

The T28/T95 was designed to be used for attacking the heavy defenses expected of the German Siegfried Line.[4] The gun selected was known to have very good performance against concrete and "expected to be extremely effective at reducing heavy fortifications"[8]

The need for an assault tank was first identified in 1943, Ordnance proposing that 25 vehicles could be ready for operations. A conference in March 1944 between Ordnance Department and Army Ground Forces resulted in agreement to build five. The Pacific Car and Foundry Company were supplied with the design in March 1945, completed final design and had the first hull welded by August.[9] By the time the first tank was completed and ready for combat, the war was over.[2] The plan for five was reduced to two.

As it did not have a turret, but a fixed casemate mount instead for its main armament, and the 105 mm gun fitted could only elevate from 19.5° to -5° and traverse from 10° right to 11° left of the centerline, the T28/T95 more closely resembled a self-propelled gun, and was redesignated as "T95 Gun Motor Carriage" in 1945, but in June 1946, the vehicle was redesignated again as "Super Heavy Tank T28".[4]

Two prototypes of the T28 were built. They underwent evaluation at the Aberdeen Proving Ground and Fort Knox facilities until 1947. In 1947 one of the T28s was heavily damaged by an engine fire during trials at Yuma Proving Ground and was broken up and sold for scrap. The T28 never went into service, but was retained to test the "durability of components on such a heavy vehicle". Work on it ended before completion as the War Department decided to stop the development of vehicles of that sort of weight[10] and the T28 program terminated in October 1947. By that point the T29 and T30 turreted heavy tank designs had been built.[4] The T29 mounted the same gun as the T28 in a conventional rotating turret. The T30 was developed with a larger-caliber gun and more powerful engine.[4] The T29 program was used to test mechanical components for future tank designs[11]

Surviving vehicle

In 1974 the last prototype was discovered abandoned in a field at Fort Belvoir, Virginia. It is unknown where it spent the intervening 27 years. It is the sole remaining example of these tanks and was exhibited at the Patton Museum of Cavalry and Armor in Kentucky.[2][12] In 2011, it was shipped to its new home at Fort Benning, Georgia, where it is now on display.

Design

Front three-quarter view of the 105 mm Gun Motor Carriage T95 at the Patton Museum
Side view

The mechanical superstructure was taken from a T23.[3] The original plan was to build five prototype vehicles, with a production total of 25. Its total weight when fully equipped would have reached 95 short tons (86 tonnes).[2] To lower ground pressure, instead of two tracks, it used four tracks that projected forward of the hull, each 12.9 inches (328 mm) wide.[4] The outer tracks could be detached within two hours for rail transport: After removal, they could be fixed together to make a unit that could be towed behind the tank.[13] Due to its extreme weight and low engine power, the T28 had extremely limited obstacle-crossing ability and could not cross any of the portable bridges available at the time, and so was considered impractical in the field and not suitable for production.

The T28 had no conventional turret, with a casemate style hull instead, giving it a comparatively low profile, as the later examples of the fully enclosed Jagdpanzer-family of German tank destroyers, not entirely dissimilar to the 50 short-ton weight German Jagdpanther. Its main armament was a 105 mm T5E1 gun, in a ball-shaped gun mantlet set into the vertical hull front.[2][3] The traverse was limited to 10° right and 11° left, and elevation from 19.5° to −5°. When traveling, the gun was locked at the maximum elevation.[4] The only other armament was a .50 cal. (12.7 mm) M2 Browning machine gun on a ring mount above the commander's hatch for anti-aircraft use.[2][14] The main gun — 65 calibres long — had a muzzle velocity of 3,700 feet per second (1,130 m/s), with a range of up to 12 miles (19 km).[2][15]

The armor was very thick compared to other tanks of the time, up to 12 inches (305 mm) thick on the front. This was considered heavy enough to provide protection from the German 88 mm gun used as tank gun and anti-tank guns.[4] The lower hull front had 5.25 in (130 mm) of armor, and the sides 2.5 in (64 mm). The suspension system and lower hull were covered with 4-in (100 mm) thick steel skirts.[4] The engine was a gasoline-powered Ford GAF V-8, delivering 500 hp,[2] at 2600 rpm though the Torqmatic transmission, which left the vehicle underpowered, geared down to a top speed of about 8 mph (13 km/h) and greatly limited its obstacle-climbing capability.[4][16]

See also

Notes

  1. Hunnicutt p62
  2. 2.0 2.1 2.2 2.3 2.4 2.5 2.6 2.7 2.8 Lua error in package.lua at line 80: module 'strict' not found.
  3. 3.0 3.1 3.2 3.3 Lua error in package.lua at line 80: module 'strict' not found.[page needed]
  4. 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 4.8 4.9 Lua error in package.lua at line 80: module 'strict' not found.
  5. Hunnicutt p61
  6. Hunnicutt p62
  7. Hunnicutt p65
  8. Hunnicutt p61
  9. Hunnicutt p61-2
  10. Hunnicutt p65-66
  11. Hunnicutt p74
  12. Patton Museum List of Exhibits
  13. Hunnicutt p65
  14. Hunnicutt p196
  15. Hunnicutt p69
  16. Hunnicutt p64
  • Hunnicutt R. P., Firepower: A History of the American Heavy Tank. Presidio.

External links