This article is about the W49 nuclear warhead. For Astronomical region, see Westerhout 49.
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. It was 20 inches (51 cm) in diameter and 54 to 58 inches (137 to 147 cm) long depending on model, weighing 1,640 to 1,680 pounds (744 to 762 kg), and had a design yield of 1.44 megatons.