Mark 22 nuclear bomb

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The Mark 22 nuclear bomb (Mk-22) was the first thermonuclear device test by the University of California Radiation Lab (UCRL). The test was part of the Koon shot of Operation Castle. The Mk-22 failed to achieve anything like its intended yield due to premature heating of the secondary from exposure to neutrons. As the other UCRL test planned for the Castle series, the liquid fueled "Ramrod" device had the same basic design flaw, that test was canceled. Within a month of the bomb’s failure, the Mk-22 was terminated because the United States Atomic Energy Commission realized there was nothing that could be done to salvage the design.


The Mark 22 bomb was part of Operation Castle, a high yield weapons test for thermonuclear bombs. The testing was conducted by the University of California Radiation Lab in order to find a better system, for dropping thermonuclear devices from aircraft. Before testing, the Mk-22 bomb was supposed to break new ground in weapon design, delivering one megaton of force to its target.


The Mk-22 was a thermonuclear bomb. A thermonuclear bomb is a device that uses primary nuclear fission to ignite a secondary reaction. These weapons have a far greater megaton yield than bombs that only use a primary reaction. In the case of the Mk-22, the reaction between the primary and secondary fission malfunctioned due to a design flaw.


While the bomb was a part of a very promising group of tests (Operation Castle), the Mark 22 Nuclear Bomb had a flawed design which left neutrons exposed; therefore, testing for the bomb was promptly cancelled as it would not be worth the resources to find a solution.


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