Panjandrum

Panjandrum, also known as The Great Panjandrum, was a massive, rocket-propelled, explosive-laden cart designed by the British military during World War II. It was one of a number of highly experimental projects, including Hajile and the Hedgehog, that were developed by the Admiralty's Directorate of Miscellaneous Weapons Development (DMWD) in the final years of the war. The Panjandrum was never used in battle.

The DMWD had been asked to come up with a device capable of penetrating the 10-foot-high (3.0 m), 7-foot-thick (2.1 m) concrete defences that made up part of the Atlantic Wall. It was further specified that the device should be capable of being launched from landing craft since it was highly likely that the beaches in front of the defences would act as a killing ground for anyone attempting to deliver the device by hand. Sub-Lieutenant Nevil Shute calculated that over 1 long ton (1,016 kg) of explosives would be needed in order to create a tank-sized breach in such a wall. The delivery method for such a quantity of explosives posed a significant problem, and one of the concepts discussed ultimately resulted in the construction of the prototype "Great Panjandrum". The proposed device was composed of two wooden wheels, ten feet in diameter with steel treads a foot wide, joined by a central drum fitted with the explosive payload. It was to be propelled by sets of cordite rockets attached to each wheel. It was predicted that when deployed with a full 4,000-pound (1,800 kg) load, Panjandrum would achieve speeds of around 60 mph (97 km/h), simply crashing through any obstacles to reach its target. The name "Great Panjandrum" was chosen by Shute as a reference to Samuel Foote's famous extempore nonsense paragraph (though Foote's term was actually "the grand Panjandrum"), and in particular to its closing line "till the gunpowder ran out at the heels of their boots".

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