Ivy King: Meaning (information, definition, explanation, facts)

Ivy King was the explosion of what is thought be the largest pure fission nuclear bomb ever tested. The bomb was developed by America during the Truman administration as part of Operation Ivy, the development of very powerful atomic weapons in response to the nuclear weapons program of the Soviet Union.

The production of this device was hurried so it would be ready if its sister project, Ivy Mike, failed in its attempt to achieve a thermonuclear reaction. In the event, the Ivy Mike test took place a fortnight before the testing of this device although that test was not of a practical air-droppable weapon since the device weighed 82 tons.

On November 16, 1952 at 11:30 local time (23:30 GMT) a B-36H bomber dropped the bomb over Runit Island on the Enewetak Atoll, resulting in a 500 kiloton explosion at 1480ft.

The Ivy King bomb was a modified version of the Mk-6D bomb, but instead of using the implosion system that the Mk-6D had it used a 92 point implosion system initialy developed for the Mk-13. Its uranium-plutonium core was replaced by 60kg of HEU enclosed in a natural uranium tamper. Because the bomb consisted of more than 4 critical masses of HEU, the bomb had a very high chance of accidental detonation, or at least a serious criticality accident. This risk was compensated for by filling the central portion of the bomb with an aluminium/boron composite chain which was removed just before the bomb was delivered. This absorbed neutrons needed to drive the nuclear reaction, and also prevented the pit from collapsing into a supercritical core if the surrounding explosives were accidently detonated.