(Gun Nr. 21 on Carriage Nr. 3)
At 8:31 a.m. on 25 May 1953 this gun fired the world's first atomic artillery round, at Camp Desert Rock, Nevada. 19 seconds later and 7? miles distant, the shell that could wipe out an enemy division exploded on target with a roaring violence equal to 15,000 tons of TNT. 3,100 participating military officers and men crouched some 5,000 yards from the churning mass of heat and flame that surrounded the core of the atomic fireball. The event was a milestone in military history and in the advancement of nuclear weaponry.
The test was carried out at the request of the Atomic Energy Commission and as directed by the Joint Chiefs of Staff. Major General A.M. Harper, Commanding General, The Artillery Center, and Commandant, The Artillery School, Fort Sill, was charged with responsibility for the firing. Cannoneers of "A" Battery, 867th Field Artillery Battalion of Fort Sill manned "Atomic Annie" for the shot, thus becoming the first ground troops in history to deliver a nuclear weapon.
The 280mm gun required 8 years of research to develop. When linked up with its two transporters it weighs 85 tons, has a length of 84 feet and a width of 10 feet. The barrel is 40 feet long. It could travel cross-country as well as on roads at a speed of 35 mph, had a range of 20 miles, and all-weather capability. The Mk9 projectile fired at Frenchman's Flat weighed 800 pounds.
Atomic Annie's emplaced here at the same elevation it had when firing the atomic round, 84 mils.
This plaque commemorates those individuals who were members of the Artillery Test Unit, Fort Sill, Oklahoma, whose combined efforts resulted in the successful firing of the first atomic artillery projectile at Frenchman's Flats, Nevada, on 25 May 1953, marking another milestone in the illustrious history of the Artillery.
[This text is followed by a list of over 200 service members from 11 different organizations who were part of this test]