The Economist March 12th 2022 67
Science & technologyImprovisedweaponsDARPA on the Dnieper
I
t did nottake long for Pravda, a trendy
microbrewery in Lviv, to switch from
brewing beer to mixing Molotov cocktails.
It began churning out these improvised in-
cendiaries on February 25th, the day after
Russia invaded. Equipment previously
employed for brews that won awards in
Brussels, Munich and Prague now blends
and bottles a concoction made from six
parts machine oil, three parts petrol, four
parts expanded polystyrene dissolved in a
solvent called thinner 646, and a sprink-
ling of powdered aluminium. The result
(see picture above) is soupy, sticky and
burns like crazy—the better to disable any
Russian military vehicle it is hurled at.
After running out of its own bottles, the
brewery even stooped, jokes Yuri Zastavny,
Pravda’s owner, to filling empties that had
once held the likes of Corona and Miller.
Nor are Pravda’s employees content on-
ly to mix Molotovs. They are also fashion-
ing caltrops. These are tetrahedral struc-
tures with a spike at each vertex, which
means that, however they fall, one spikepoints upwards. Caltrops have been used
as “area denial” weapons on battlefields
since ancient times (Alexander the Great
employed them to beat the Persians at Gau-
gamela in 331bc). Originally, they were in-
tended to bring down charging cavalry and
war chariots. Now their targets are vehicle
tyres and soldiers’ boots. Pravda’s people
make them out of “rebar”—the lengths of
twisted steel used to reinforce concrete.Points of contention
For rapid deployment on city streets that
need barricading, caltrops can be welded
to chains. Elsewhere in Lviv, other forms of
barricade are being prepared. These are
six-vertex anti-tank devices called hedge-hogs, made from lengths of surplus train
rail. They look like giant versions of chil-
dren’s jacks. Deployed en masse they can
halt tanks in their tracks, opening them to
attack by the men and women with the Mo-
lotovs. And the workshops of Lviv are not
alone. Defences of this sort are being
cranked out all across Ukraine. Those with-
out access to rebar fashion caltrops by
bending and welding nails. And rows of
spikes fixed to sheets of thick rubber will
also make infantry think twice.
Ukraine has many engineers, computer
programmers and other technical special-
ists who are used to getting things done
with limited resources. Sviatoslav Yurash,
a young parliamentarian from Lviv, who is
in Kyiv to fight, attributes this inventive-
ness to the country’s distinctive cultural
heritage. The “bureaucratic mayhem” of
Soviet rule, he says, pushed people to de-
vise creative workarounds. That served as a
foundation for the three decades of mar-
ket-oriented reforms that followed inde-
pendence. These rewarded an entrepre-
neurial spunk which, he observes, is “com-
ing in handy right now”. Vladimir Yatsen-
ko, a film producer also in Kyiv to fight,
describes this inventive spirit as “our na-
tional darpa”, a reference to a famous
American military-research agency.
Some of the makeshift weapons ap-
pearing as a consequence of this ingenuity
are, indeed, fearsome. Need a grenade
launcher? Grab a shotgun and fix a steelMakeshift weapons are pouring out of Ukraine’s ateliers→Alsointhissection
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