The W38 was an American thermonuclear warhead used in the early to mid 1960s as a warhead for Atlas E and F, and LGM-25 Titan IICBMs. It was first built in 1961 and was in service from 1961 to 1965. 70 were deployed on Titan I missiles and 110 on Atlas missiles. It used the Avco Mark 4 reentry vehicle.
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