Mark 19

The Mark 19, a projectile weapon, added nuclear capability to artillery that previously fired conventional shells. W19, also called Katie, was an American nuclear artillery shell created on the basis of an earlier W9. It was designed for a special 280 mm howitzer. Adopted in service in 1955, it was withdrawn in 1963. The caliber of the W19 was 280 mm, weight - 270 kg. The yield of this cannon-fired nuclear charge was 15-20 kt.