A circular shaped anti-personnel bomb that, when dropped by the Canberra from level flight, gave a natural dispersion pattern. The bomb would strike the surface activating the fusing mechanism and then bounce into the air to detonate about six metres above ground.
This bomb was an improved version of that used by the Rhodesian Air Force. About 300 could be loaded into the bomb bay.
Due to the sphere shape, when released they spread apart both laterally and vertically because air pressure builds up between them and pushes them away from each other. The Alpha is a hallow sphere(155mm external diameter.) pressed out of 3mm plate with two halves welded together. Inside the outer casing is a smaller sphere of 8mm steel. Between the two spheres is packed 240 hard black rubber "bouncing" balls of 15mm diameter. (Similar to those glow in the dark type bouncing balls kids have.) When dropped from low and fast aircraft, they hit the ground at less than 17 degrees from the horizontal. On impact most of the rubber balls compressed against the outer wall, thus creating forward bounce for about 60ft in the direction of the aircraft and rising no higher than 12ft. The inner sphere is similar to a grenade and on impact with the ground the fuze fired a cap with a 7 sec delay. The bomb exploded between 6 - 12 ft above the ground dispersing on average one lethal fragment per square yard with a radius of 15 yards from explosion. The Canberra carried 300 Alpha bombs in groups of 50 inside six hoppers fitted to the bomb bay and was operated electrically. They could be dropped in salvo or in ripples.
Canberra (in bomb bay)