Flechette

A flechette /flɛˈʃɛt/ fleh-SHET is a pointed steel projectile, with a vaned tail for stable flight. The name comes from French fléchette, "little arrow" or "dart", and sometimes retains the acute accent in English: fléchette.

In World War I, darts, also known as flechettes were dropped from aircraft to attack infantry.

Small-arms makers are attracted by the exterior ballistic performance and armor-piercing potential of flechettes. A number of attempts have been made to field flechette-firing small arms.

Work at Johns Hopkins University in the 1950s led to the development of the direct injection antipersonnel chemical biological agent (DIACBA), where flechettes were grooved, hollow pointed, or otherwise milled to retain a quantity of chemical biological warfare agent to be delivered through a ballistic wound. The initial work was with the nerve agent VX, which had to be thickened to deliver a reliable dose. Eventually this was replaced by a particulate carbamate. The US Biological Program also had a microflechette to deliver either botulinum toxin A or saxitoxin, the M1 biodart, which resembled a 7.62 mm rifle cartridge.

Several underwater firearms were experimented with using flechettes.

During the Vietnam War the United States employed 12 gauge combat shotguns that were used with flechette loads that consisted of around 20 flechettes per shell. The USSR/Russian federation had the AO-27 rifle as well as the APS amphibious rifle, and other countries have their own flechette rounds.

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