The
W54 was one of the smallest nuclear warheads deployed by the United States. It was a very compact
implosion-type nuclear weapon design, designed for tactical use and had a
very low yield for a nuclear weapon of + - 10 tons equivalent TNT (Horishima was a nominal 20KT (20,000 tons equivalent TNT).
There were four variants that share the same basic core:
a nuclear system which is 10.75 inches diameter (270 mm), about 15.7 inches long (400 mm), and weighs around or slightly over 23 kg.
The
W54 style warhead was known to be
used on the M-388 Davy Crockett, a tactical nuclear recoilless rifle projectile that was deployed by the United States during the Cold War.
A Davy Crockett casing preserved in the United States
Army Ordnance Museum
The
W54 is small enough to be deployed as a SADM (Special Atomic Demolition Munition) or so called "Backpack Nuke." The United States Air Force also developed a project using the
W54, on the
AIM-26 Falcon. It is notable for being the only U.S. guided
air-to-air weapon with a nuclear warhead. It was intended to destroy formations of Soviet bombers at a time when guided missiles were not accurate enough to produce high-probability kills with small conventional warheads.
After the AIM-26 Falcon was retired, 300 units were rebuilt into an improved configuration with a higher yield and re-designated the
W72. These warheads were then used to produce a number of nuclear versions of the
AGM-62 Walleye television guided glide bomb system. The W72 variant had a yield of around 600 Tons of TNT or 0.6KT and were in service till 1979.
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