W49

The W49 was an American thermonuclear warhead, used on the Thor, Atlas, Jupiter, and Titan I ballistic missile systems. W49 warheads were manufactured starting in 1958 and were in service until 1963, with a few warheads being retained until 1975.The W49 has been described as a design derivative of the B28 nuclear bomb nuclear warhead design.The W49 was 20 inches in diameter and 54 to 58 inches long depending on model, weighing 1,640 to 1,680 pounds.
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Exposure to other and unspecified inanimate mechanical forces