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The Durchbruchswagen 2 was the second prototype of a 30 ton break-through tank that was an early stage in the development of the Panzer VI Tiger.
Henschel received an order to produce the chassis for a 30 ton tank in January 1937. The first version, the Durchbruchswagen 1, used a three stage Cletrac stearing system, but by the middle of 1937 Henschel was already planning to build a second prototype, using multiple stage steering gear.
The D.W.2 was apparently physically very similar to the D.W.1. It had a boxy hull and superstructure. The superstructure had a flat front, above the front road wheel, and was the same width as the tracks. The turret ring had a diameter of 1500mm. The sides of the D.W.1 were made in two parts, bolted together just behind the fighting compartment. The D.W.2 may have had one piece sides, or they might have been introduced on the VK 30.01 (H). There were five road wheels on each side, constructed from steel, with solid rubber double tire, supported on torsion bars.
The D.W.2 used a new steering system. The D.W.1 had used three Cletrac steering gears, arranged in series, on each track. The D.W.2 retained the first Cletrac stage, which produced one fixed turning circle without losing engine power to brakes (using an idler that could be turned on or off to alter the output speed of the transmission). This was connected to a standard three stage differential, presumably with further steering control provided by brakes applied to the tracks, as in simple differential steering systems.
The new system rotated in the opposite direction to the system used in the D.W.1, so the final drive, brakes, gear box and even the torsion bars needed to be modified. The final drive was modified, reducing the gear reduction from 1-21.5 to 1 to 12. The torsion bars had the soft springs used on the D.W.1 removed, and were made stronger. The track was reduced in pitch from 300mm to 260mm, and the ride was said to have been much smoother.
The Durchbruchswagen chassis was tested during 1938, and on 9 September 1938 Henschel received permission to continue development of a 30 ton tank, under the new designation of VK 30.01.
Krupp had the task of building a turret for the D.W.1 and D.W.2. It was to be armed with the same 7.5cm KwK L/24 tank gun as the Panzer IV, although Krupp was allowed to add extra armour to protect the gun. In March 1937 the details of the turret were set out. It was to use a 1500mm turret ring, had 50mm thick sides, a 20mm gun mantlet and 15mm roof. A radio receiver was to be mounted behind the gun. The first turret wasn't completed until 1939, by which time work had moved onto the VK 30.01. A single version of the D.W. turret was completed, and in 26 May 1939 Krupp was ordered to ship it to Madgeburg to be displayed alongside the Panzer IV.