Science: Handy A-Bombs

How big is an atomic bomb? It took a B-29 to carry the first one, dropped on Hiroshima, which may have weighed more than 10,000 Ibs. The Army’s announcement last week that it will abandon its monstrous, 11-in. atomic cannon tells how much the bombs have shrunk. The new atomic shells will fit an 8-in. gun. Since they will have to withstand the shock of firing, they will be much like ordinary 8-in. shells. They will have an internal cavity about 22 in. long and about 5½ in. in diameter in the center. This is apparently big enough for the works of a modern atomic bomb, although the steel walls of the shell may play some part in making the nuclear explosion efficient.

Eight-inch shells weigh about 240 Ibs.; so the bomb itself will not weigh more than that, and it may weigh much less since the casing may be lighter than the steel parts of the shell. A fighter-bomber could carry 16 such bombs, each powerful enough to knock the heart out of a good-sized city. A B-47 could carry 50 or more of them on a long flight, and distribute them over a large industrial complex. Atomic shells for 8-in. guns are apparently an accomplished fact, although none has been tested in actual artillery. Next step will be an atomic shell to fit a 4.2-in. mortar. The Army’s nuclear experts believe that this will be only a matter of time. When shells of this size are available, they can be fired from tanks. If made into bombs, they can be carried by the hundreds in jet bombers and scattered like confetti. One school of nuclear-weapons thought maintains that many small bombs will have more military effect than a few H-bombs that “over-bomb” a limited area.