T32 Heavy Tank (Family)
Contents
Description
The Heavy Tank T32 and Heavy Tank T32E1 were a series of heavy tank prototypes built after World War 2 and using as many M26 Pershing components as possible, especially in the hull.
Vehicles
History
Genesis
The Army saw the success of the M4A3E2 up-armoured Sherman tank which was deployed to Europe in 1944. As such, on 7 December 1944, the Army Ground Forces requested that a new heavy tank project be created by the Ordnance Department to create a version of the M26 Pershing with heavier armour.
Two projects resulted from this, the first of which was simply an M26 with heavier armour, designated as the Heavy Tank T26E5 (later redesignated as a medium tank). The second project was of a new tank type that used components of the M26 Pershing - as many components of it as possible.[1]
Development
As of 8 February 1945, OCM 26606 called for the construction of four prototypes for the second project, which was to be designated Heavy Tank T32. Approval of the project was granted two months later in March 1945. A mock-up of the T32 was nearly ready by 10 April 1945, with eighty percent of the blueprints released by that point.
T32 Pilot 1 was completed on 15 January 1946 and Pilot 2 was completed on 19 April 1946. They were shipped to Aberdeen Proving Ground for testing immediately after completion. Pilot 3 was completed on 14 May 1946 and Pilot 4 was completed on 19 June 1946. Pilot 3 was sent to Fort Knox for testing while Pilot 4 was kept at the Detroit Arsenal. The third and fourth pilots would be designated as Heavy Tank T32E1 on 9 August 1946 in accordance with OCM 28680.[1]
Heavy Tank T32
The crew complement of the T32 was five: a driver and assistant driver/machine gunner in the hull and the gunner, commander, and loader in the turret. The hull was based on that of the M26 Pershing but was elongated and featured armour changes, along with a new powerplant and redesigned engine compartment. A new turret was fitted that was more different from that of the M26 but still utilized components from the Pershing.
A 770 horsepower Ford GAC V12 engine and an EX-120 cross-drive transmission with two forward and one reverse speed made up the powerplant, a similar powerplant to that used on the Heavy Tank T29. The T32 weighed approximately 120,000 pounds combat ready and could attain a speed of 22 miles per hour (35.4 kilometers per hour). The maximum range, on road, was 100 miles (160.9 kilometers). The hull was mostly similar to the Pershing except it was elongated with a seventh road wheel on each side compared to only six on the M26; the torsion bar suspension was retained. The tracks were the same 23 inch T80E1 tracks as used on the Pershing but they were fitted with 5 inch extended end connectors to reduce ground pressure. Armour was to be thickened to five inches (127 mm) at 54 degrees on the upper glacis and 95 mm at 59 degrees on the lower glacis; the front armour was of cast construction. The side and rear armour was largely the same as the Pershing - 3 inches (76.2 mm) on the sides and 2 inches (50.8 mm) on the rear - except for the lengthened hull and redesigned engine compartment for the new powerplant. There was a .30 caliber (7.62 mm) M1919A4 machine gun in a ball mount on the right side of the upper glacis for use by the assistant driver/machine gunner. Two hinged hatches were provided for both the driver and assistant driver, located overhead, with a single periscope in each hatch.
A newly designed turret was fitted. Armour ranged from 6 inches (152.4 mm) on the rear and sides to 11¾ inches (298.45 mm) on the front. The main armament was to consist of a 95 mm T15E2 high velocity gun using two piece ammunition, which was also used on variants of the T29. The gun could elevate 20 degrees and depress 10 degrees. Due to the long gun with large two piece ammunition, the ammunition stowage had to be rearranged. A .30 caliber (7.62 mm) M1919A4 machine gun was fitted coaxial to the main gun and there were also two mounting points for a .50 caliber (12.7 mm) M2HB machine gun, one on the rear of the turret roof and one in front of the commander's cupola. The ammunition load consisted of 54 90 mm rounds, 4,000 .30 caliber rounds, and 550 rounds of .50 caliber ammunition. A radio was installed in the turret bustle.[1]
Heavy Tank T32E1
The third and fourth T32 pilots were redesignated as T32E1s shortly after construction, they had a number of differences from the first two pilot vehicles. The biggest difference was in rolled rather than cast construction of the front hull armour, which also saw the removal of the bow ball-mounted machine gun. The periscopes for the driver and assistant driver/machine gunner were relocated from the hatches to the roof armour directly in front of the hatches, and the hatches were also changed from a hinged type to a pivoting design to prevent them from getting in the way of turret rotation when open. Otherwise, the T32E1 was identical to the T32.[1]
Production and Service
Total Production: 4
Production remained at two T32s and two T32E1s. The T32 never entered production or service because they arrived after the war had ended so there was no longer any need for them, but the program was a great learning experience for the Army. Notably, it was the first tank to be fitted with the EX-120 cross-drive transmission and tested at Aberdeen Proving Grounds and Fort Knox. The transmission proved to have reliability issues leading to excessive maintenance requirements, but it gave useful insight that later resulted in the CD-850 series of cross-drive transmissions that would eventually see production.[1]