With the destructive potential of nuclear technology proven beyond doubt after the bombings of Hiroshima and Nagasaki, the United States not only increased the number of atomic tests, but also explored other formats and "delivery methods" for these weapons. One of its most striking results was the M65 cannon, better known as Atomic Annie. The prototype's only live-fire test took place during Operation Upshot-Knothole, and its success led to the production of roughly twenty units, deployed in Europe and Korea.
If we take a moment to look at the world of video games, the Fallout series features a very special weapon called the Fat Man, probably in "honor" of the bomb that fell on Nagasaki. The weapon is absurd by any measure, as it is a catapult that fires miniature nuclear bombs from the shoulder, like a bazooka. However, the concept of "mobile" nuclear artillery found a real-life place with the creation of the M65 cannon, a beast of 280 millimeters with the curious nickname "Atomic Annie".
Atomic Annie: Mobile Nuclear Artillery (M65)
Editor's note: The video includes edited footage from Operation Plumbbob, which does not correspond to the cannon test.
Its history tells us that the Department of Defense ordered in 1949 the development of a piece of artillery with nuclear capability. The task was assigned to Picatinny Arsenal and engineer Robert Schwartz, who decided to increase the caliber from 240 millimeters (the largest the Army had at its disposal at that time) to 280 millimeters, taking as reference for the transport system the German heavy cannon K5. The Pentagon gave the green light, and three years later the first demonstration model was completed, which participated in President Dwight D. Eisenhower's inauguration parade in January 1953. In May of that same year, a prototype was installed at the Nevada Test Site. Its first and only shot was identified as "Grable" under Operation Upshot-Knothole, detonating a shell-type bomb of 15 kilotons at a little over ten kilometers away.
The M65 cannon could be prepared to fire in less than fifteen minutes, and return to its transport configuration in another fifteen. The complete system weighed 75.5 metric tons, and its effective range was about 30 kilometers. After its test in Nevada, general production began, at a cost of approximately $800,000 per cannon.
Its gigantic size, the difficulties of moving it, and the advancement of rockets and missiles made the M65 become obsolete almost as soon as it entered service; however, it remained active until 1963. Its ammunition was eventually recycled as "T-4 Demolition Units", and the United States would create even more compact nuclear weapons some years later... but that is another story.
Source: Olive-Drab (via Archive.org)
