The Großkampfwagen or "K-Wagen" (short for G.K.-Wagen) was a German super-heavy tank, two prototypes of which were almost completed by the end of World War I.
In June 1917, before the first A7V tanks had been completed, the German War Ministry ordered the development of a new superheavy tank intended to be used in break-through situations. Design work was carried out by Joseph Vollmer, a Reserve Captain and engineer working for the Verkehrstechnische Prüfungskommission ("Transport-technologies Board of Examiners" of the army), and a Captain Weger.
On June 28 1917 the War Ministry approved the draft design and ordered ten examples, five to be built by the Riebe ball-bearing factory in Berlin and five by Wegman and Co. of Kassel.
Despite the obvious absurdity of the whole project, two prototypes were built at the request of Hindenburg, and were almost complete by the end of the war.
The hull of the K-Wagen consisted of six modules that could be transported separately by rail: the control room, the fighting room, the engine room, the transmission room and the two sponsons. The commander could give orders to the crew by means of electric lights: fire control was comparable to that of a destroyer, the Germans seeing the vehicle as a veritable "landship". The drivers would have had to steer the vehicle blindly, directed by the commander.
The K-Wagen never became operational as under the conditions of the Armistice Germany was forbidden to possess tanks. One of the tanks, "Ribe" was complete at the end of the war, but it never left the factory and was scrapped under the watchful eyes of the Military Inter-Allied Commission of Control. However, in 1942 Hitler had a full scale wooden mock-up built for comparison with his own examples of tank gigantomania.
Text: Wiki (EN)