Air burst

An air burst is the detonation of an explosive device such as an anti-personnel artillery shell or a nuclear weapon in the air instead of on contact with the ground or target or a delayed armor-piercing explosion. The principal military advantage of an air burst over a ground burst is that the energy from the explosion (as well as any shell fragments) is distributed more evenly over a wider area; however, the peak energy is lower at ground zero.

The term may also refer to naturally occurring air bursts arising from the explosions of incoming meteors as happened in the Tunguska event, the 1930 Curuçá River event, and the Chelyabinsk meteor event.

Air burst artillery has a long history. The shrapnel shell was invented by Henry Shrapnel of the British army in about 1780 to increase the effectiveness of canister shot. It was widely used by the time of the War of 1812 and stayed in use until it was superseded during the First World War. Modern shells, though sometimes called "shrapnel shells", actually produce fragments and splinters, not shrapnel.

Air bursts were used in the First World War to shower enemy positions and men with shrapnel balls to kill the largest possible number with a single burst, assuming that the burst was directly in front of the trench in which the men were positioned.

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