Fat Man

The Fat Man is a shoulder-fired, catapult weapon system that launches Mini Nukes. It appears in Fallout 3, Fallout: New Vegas, Fallout 4, Fallout 76, Fallout Shelter and Fallout: The Board Game.

Background
 The M42 Fat Man was developed at Fort Strong near Boston. Development began in February 2076, with the goal being the development of a man-portable tactical nuclear launcher easy enough for use by troops on the ground, to destroy reinforced and entrenched positions. At first, warheads were too heavy to clear the blast radius fast enough to provide safety for the operator. Stripping them to the minimal possible size failed to produce an acceptable result. The development team decided to increase the power of the launcher unit, and considered using railgun technology to accelerate the warhead, but would require soldiers to carry a suitcase-sized power pack.

Live-fire testing claimed two lives, with no remains recovered and the commanding officer in charge of the project, General Brock, ordered his subordinates to send sand packed in an urn to their relatives. The project experienced a breakthrough in December 2076, when the project lead discovered a solution for the launcher problems. Based on the spigot mortar mechanism, the launcher would only have to accommodate a firing through and system, relying on mechanical launching, rather than chemical or electrical means. The Fat Man warhead would be propelled by a sub-charge embedded inside the warhead, "catapulting" the warhead through the air to the target, providing sufficient range with no smoke trail that could reveal the firing team to the enemy.

By September 2077, after one hundred test firings, the weapon was complete and ready to be shipped to units overseas. The units were manufactured and shipped together with the appropriate warheads to select locations throughout the United States. 

Behind the scenes

 * Fat Man was the codename for the atomic bomb that was detonated over Nagasaki, Japan by the United States on August 9, 1945.
 * The weapon was renamed "Nuka Launcher" in the Japanese version of Fallout including Fallout 3 and Fallout: New Vegas. 

Video
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