The Economist explains

What are flechettes, a brutal weapon used in Ukraine?

They kill and maim indiscriminately and are uncommon in modern warfare

BUCHA, UKRAINE - APRIL 16: Svitlana Chmut holds flechettes, small arrow-like projectiles dispersed by a Russian artillery shell, on April 16, 2022 in Bucha, Ukraine. (Photo by Alex Horton/The Washington Post via Getty Images)

RESIDENTS OF BUCHA, a town on the outskirts of Kyiv, the Ukrainian capital, report finding thousands of miniature darts embedded in buildings and cars. The metal projectiles, less than 3cm long and known as flechettes, from the French for “little arrows”, have a particularly brutal reputation and are unusual in modern warfare. Why is Russia using them?

The weapon hardly has an illustrious history. It was invented in Italy in the early 1900s and adopted by all sides during the first world war. The arrows were typically 12cm long with fins for stability and were dropped from aircraft in canisters of tens or hundreds. They were ineffective and superseded by explosive bombs.

America then developed a new, more lethal generation in the 1950s, in a programme codenamed Lazy Dog. A 225kg bomb split open to release more than 10,000 projectiles, each 44mm long. They struck with the force of a bullet and, at around nine hits per square metre, had a good chance of killing anyone in the area. Unlike other bombs, the Lazy Dog made little noise except the patter of steel rain. In Vietnam, America also used artillery-fired flechettes, known as Beehive rounds because of the buzzing of the darts. They could be fused to burst immediately on leaving a gun’s barrel, turning it into a giant shotgun. Gruesome, apocryphal stories told of victims found nailed to trees.

American army studies on animals show that at high speed, small flechettes tumble when they enter the body, producing disproportionately severe injuries. They can also penetrate further and can pass through bone. In the early 2000s an Israeli human-rights group attempted unsuccessfully to stop flechettes being used in the occupied West Bank. Efforts to have them subject to specific international laws, as cluster bombs and land mines are, have failed.

Apart from acting as grapeshot to fend off attacks at short range, flechettes have few advantages over similar munitions. Their footprint is that of a wide cone, not the 360 degree spread of a shell. And they cost much more to produce than fragmenting rounds. Henry Shrapnel’s original eighteenth-century design for a bursting shell was filled with metal balls, but in the second world war scientists found that any bomb with a metal casing of suitable thickness produced lethal fragments. By contrast, each flechette needs to be made individually with an aerodynamic design.

Neil Gibson of Fenix Insight, an explosive-disposal consultancy, identified the flechettes in Bucha as coming from a Russian 122mm 3Sh1 artillery round. Images taken near the town appear to show a destroyed 122mm gun with unfired 3Sh1 rounds scattered about it. Russian artillery usually use fragmenting rounds, which are effective against a wider range of targets, including buildings and light-armoured vehicles. Russia might have issued small numbers of flechette rounds for defensive purposes; logistics problems may have meant that batteries began to use what they had indiscriminately. It is also possible the aim was simply to terrorise.

Read more of our recent coverage of the Ukraine crisis

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