The T28 "Superheavy Tank" is the heaviest armored vehicle ever produced by the United States ... about 95 tons. Designed late in WW-II as an assault vehicle to penetrate fixed German defense positions such as the Siegfried Line, the T28 carries the thickest armor ever fitted to an armored vehicle ... approx. 12" frontal and 8" side, some of it well sloped. This is more like Battleship armor than tank armor! The German's famed 88 mm would be nearly worthless against such a vehicle.
The T28's turretless design saved a LOT of weight, which allowed much heavier armor to be fitted. Since the vehicle was designed for frontal assault, a full rotating turret was not needed. The gun did have limited traverse in the hull, allowing some freedom of target choice without turning the whole vehicle. The gun itself was a very-high velocity 'long' 105mm. Compared with even the 90mm in the T26 Pershings, this was a powerful weapon; and was sufficient to 'crack' most any target the T28 might encounter.
To speed development, The T28 used as many 'off the shelf' parts as possible. The entire suspension consisted of slightly modified M4E8 components. Many of the hull fittings were 'Sherman', as was the Ford V-8 engine and matching transmission. A much lower final drive ratio was used, to move so heavy a vehicle. Top speed was about 10 mph. The unique paired tracks gave the vehicle a very acceptable ground pressure not much different than a Sherman. It weighs three times as much as an M4, but puts almost three times as much track surface on the ground.
A unique feature of the T28 were the detachable outboard track units. On each side of the main hull were attached massively armored supplementary sub-hulls, each with a fully functioning track. These could be removed from the main hull, clamped together to form a trailer, and towed behind the T28. This reduced the width to an acceptable value, allowing the vehicle to pass through city streets, be rail transported, and to fit in Landing craft. The outboard units would need to be reattached prior to combat. Two small moveable cranes are carried by the T28 to assist in mounting/detaching these side units. Supposedly, a well trained crew could do this relatively quickly.
One 'dumb' feature are the two very visible brake drums carried on the outside of the T28. These attach to the track-sprocket of the outboard track units when they are detached from the vehicle. This weird tracked trailer had NO regular brakes! To keep it from overrunning the towing vehicle, crew members, on FOOT, wrapped ropes around these drums, and pulled! This created a drag, slowing the trailer. It worked, but won't win any prizes for elegance! Oh, well, remember that this was only a prototype vehicle. If it had gone into production perhaps something better would have been used.
While large, the T28 is smaller than a German 'Maus'. The Maus was designed as a real 'Tank', with full rotating turret, and heavy armor all around. The price it paid for this was an astonishing weight of about 180 tons, with corresponding lack of mobility, transport problems, and overloaded drive components! The T28, on the other hand, was a special purpose vehicle, with much heavier armor (admittedly only on the front and sides), yet far less overall weight.
As an assault vehicle, the T28 was formidable. Low and squat, it presented very little target, and what did show was almost impenetrable. Only plunging artillery fire and anti-tank mines would much have bothered it. True, the T28 was SLOW, but this was not overly important for it's designed purpose. Alone, in open country, the T28 could be easily avoided or outflanked, but it was not envisioned to use in such a situation. Imagine, rather, a long row of T28's assaulting a fixed fortification, well backed by lesser armor, infantry, artillery, and air support. This was a vehicle to be used from a position of military superiority, to 'crack' tough spots in a defense perimeter.
Ultimately, it wasn't needed. The Germans abandoned the Siegfried line. Development of the vehicle continued into the Korean War years, then was terminated. Briefly, the vehicle was reclassified as a Gun Motor Carriage, T95, then back as a tank, type T28. Surviving records (at the time) indicated that both prototypes had been destroyed or scrapped. Obviously, this was wrong, as the Patton Museum's example clearly demonstrates.
