The 280mm Atomic Cannon - Nuclear Artillery Test

Excerpt from recently updated Operation Upshot-Knothole

From Wikipedia, the free encyclopedia http://en.wikipedia.org/wiki/M65_Atom...

Picatinny Arsenal was tasked to create a nuclear capable artillery piece in 1949. Robert Schwartz, the engineer who created the preliminary designs, essentially scaled up the 240mm shell (then the maximum in the arsenal) and used the German K5 railroad gun as a point of departure for the carriage. (The name "Atomic Annie" likely derives from the nickname "Anzio Annie" given to a German K5 gun which was employed against the American landings in Italy.) The design was approved by the Pentagon, largely through the intervention of chief of the Ballistics Section of the Ordnance Department's Research and Development Division, Samuel Feltman, and a three-year developmental effort was begun. The project proceeded quickly enough to produce a demonstration model to participate in Dwight Eisenhower's inaugural parade in January of 1953.

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 turns on 28 ft wide, paved or packed roads. The artillery piece could be unlimbered in 15 minutes and then returned to traveling configuration in 15 minutes more.

On May 25, 1953 at 8:30am local time, 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 E. Wilson; it resulted in the successful detonation of a 15 kt shell (warhead W9) at a range of 7 miles. This was the first and only nuclear shell to be fired from a cannon.

Subsequent to the successful test, there were at least 20 of the cannons manufactured at Watervliet and Watertown Arsenals, at a cost of $800,000. They were deployed overseas to Europe and Korea, often continuously shifted around to avoid being detected and targeted by opposing forces. Due to the size of the apparatus, their limited range, the development of nuclear shells compatible with existing artillery pieces (the W48 for the 155mm and the W33 for the 203mm), and the development of rocket and missile based nuclear artillery, the M65 was effectively obsolete soon after it was deployed. However, it remained a prestige weapon and was not retired until 1963.

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Closed Caption:

got 10 25 may protested another delivery
system
the Army's 218 millimeter gun when the
shot was added to the program some
additional effects test were scheduled
to observe results of the low best
height approx 520 feet above ground
since no gun type Assembly had been
detonated since the Hiroshima bomb the
weapons development scientists had on
this shot their first opportunity to
study the nucleonic behavior and
fireball configuration of such a device
yield 15 kilotons unlike the situation
with an implosion weapon the scientists
were here able to observe fireball
growth from a body official material
whose exact shape and dimensions at the
moment of detonation were known as