The M65 Atomic Cannon, often called Atomic Annie, was a towed artillery piece built by the United States and capable of firing a nuclear device. It was developed in the early 1950s, at the beginning of the Cold War, and fielded by 1953 in Europe and Korea.
The cannon was transported by two specially designed tractors, both capable of independent steering in the manner of some extra-long fire engines. Each of the tractors was rated at 375 hp, and the somewhat awkward combination could achieve speeds of 35 miles an hour and negotiate right angle turns on 28 ft wide, paved or packed roads. The artillery piece could be unlimbered in 15 minutes, then returned to traveling configuration in another 15 minutes.
On May 25, 1953 at 8:30am, the Atomic Cannon was tested at Nevada Test Site (specifically Frenchman Flat) as part of the Upshot-Knothole series of nuclear tests. The test — codenamed Grable — was attended by then Chairman of the Joint Chiefs of Staff Adm. Arthur W. Radford and Secretary of Defense Charles Erwin Wilson; it resulted in the successful detonation of a 15 kt shell (W9 warhead) at a range of 7 miles. This was the first and only nuclear shell to be fired from a cannon (the Little Feller 1 test shot of an M388 used a Davy Crockett Weapon System which was a recoilless smooth bore gun firing the warhead mounted on the end of a spigot inserted in the barrel of the weapon.)
