W66

The W66 thermonuclear warhead was used on the Sprint anti-ballistic missile system, designed to be a short range interceptor to shoot down incoming ICBM warheads.

The W66 was a low yield (details not declassified, but reportedly a few kilotons) thermonuclear bomb. It was designed to destroy or disable an incoming warhead using neutron flux, and to a lesser extent X-ray and blast effects.

The W66 was 18 inches in maximum diameter and 35 inches long, with a weight of approximately 150 pounds.

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