The Landkreuzer P 1500 Monster was a purported German pre-prototype super-heavy self-propelled gun designed during World War II. While mentioned in some popular works, there is no solid documentation for the program’s existence, and it may be an engineer’s amusement or an outright hoax.
Development
On 23 June 1942 the German Ministry of Armaments proposed a 1,000-tonne tank — the Landkreuzer P. 1000 Ratte. Adolf Hitler expressed interest in the project and the go-ahead was granted. In December, Krupp designed an even larger 1,500 tonne vehicle — the P. 1500 Monster. The P. 1500 was to be 25 m long, weighing 1800 tonnes, with a 250 mm hull front armor, four Daimler-Benz MB.501 diesel aero engines, and an operating crew of over 100 men. This "land cruiser” would have been a self-propelled platform for the 800mm Dora/Schwerer Gustav K gun artillery piece also made by Krupp – the heaviest artillery weapon ever constructed by shell weight and total gun weight, and the largest rifled cannon by calibre. The Schwerer Gustav fired a 7-tonne projectile up to and was designed for use against heavily fortified targets. The main armament could have been mounted without a rotating turret. Such a configuration would have allowed the P. 1500 to operate in a similar manner to the original 800mm railroad gun and Karl 600mm self-propelled mortars, launching shells without engaging the enemy with direct fire.
Issues
Development of the Panzer VIII Maus had highlighted significant problems associated with very large vehicles, such as their destruction of roads/rails, their inability to use bridges and the difficulty of strategic transportation by road or rail. The bigger the vehicle, the bigger these problems became. Propulsion had also proved problematic in the development of the Maus: The prototype had failed to meet its specified speed requirements which meant that even larger vehicles such as the P. 1500 were likely to be slow-moving. Among these was the P. 1500's weakness to air attack, as the Allies had air supremacy from 1943/44 onward. This itself would mean it would have required a detachment of anti-aircraft vehicles as defense. In 1943, Albert Speer, the Minister for Armaments, canceled both the Ratte and Monster projects.
