The Economist Asia - February 10, 2018

70 The EconomistFebruary 10th 2018

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A

N ATTACK on Russian forces in Syria on

January 5th by 13 home-made drones

is a good example of “asymmetric” war-

fare. On one side, exquisite high-tech

weapons. On the other, cheap-as-chips dis-

posable robot aircraft. Ten of the drones in-

volved attacked a Russian airbase at

Khmeimim. The other three went for a

nearby naval base at Tartus. Rather than

being quadcopters, the most popular de-

sign for commercial drones, the craft in-

volved in these attacks (some of which are

pictured above) resembled hobbyists’

model aircraft. They had three-metre

wingspans, were built crudely of wood

and plastic, and were powered by lawn-

mower engines. Each carried ten home-

made shrapnel grenades under its wings.

According to the Russian Ministry of

Defence, which has so far refused to say

who it thinks was responsible for the at-

tack, the drones were guided byGPSand

had a range of 100km. The electronics in-

volved were off-the-shelf components,

and the total cost of each drone was per-

haps a couple of thousand dollars. The air-

frames bore a resemblance to those of Rus-

sian Orlan-10 drones, several of which

have been shot down by rebel forces in

Syria. The craft may thus have been a

cheap, garage-built copy of captured kit.

These particular drones, the Russians

sembled for less than the cost of a single

shoulder-fired missile, let alone a modern

combat aircraft. America’sF-22 fighter, for

example, costs over$300m. AB-2 bomber

is even more expensive.

Even a lone drone can do plenty of

damage. In Ukraine last year, drones oper-

ated by Russian separatists (or perhaps by

Russian special forces) attacked several

ammunition dumps with incendiary gre-

nades. They destroyed a number of these

dumps, in one case setting off explosions

which blew up a staggering 70,000 tonnes

of munitions.

A growing appreciation of the threat

from small drones has led to a rush for pro-

tection. Lieutenant-General Stephen

Townsend, a former commander of Oper-

ation Inherent Resolve, America’s anti-IS

campaign, has called weaponised drones

“the number one threat facing soldiers

fightingIS”. An American navy budget

document describes the navy as “scram-

bling to improve defences against the rap-

idly evolving capabilities of remote-con-

trolled devices”. Existing defences are not

geared up to cope with small drones,

which are difficult to spot, identify and

track, and which may be too numerous to

stop. Jamming might be thought an obvi-

ous solution. Breaking the radio links be-

tween the operator and the drone, or con-

fusing itsGPSnavigation, would make a

drone crash or send it off course. Many

jammers, with names like Dedrone,

DroneDefender and DroneShield, have al-

ready been employed by various coun-

tries. Six of the drones in the Syrian attack

were brought down by such jammers, the

others by guns and missiles.

Drones are, however, becoming in-

creasingly autonomous. This means there

claim, were intercepted before they could

cause any damage. However, several Rus-

sian aircraft were apparently damaged in

an attack in Syria four days earlier, which

was also, according to some accounts, car-

ried out by drones. And there will certainly

be otherassaults of thissort. Guerrillas

have been using commercial drones since

2015. Islamic State (IS), one of the groups ac-
      tive in Syria, makes extensive use of quad-
      copters to drop grenades. In 2017 alone the
      group posted videos of over 200 attacks. IS
      has also deployed fixed-wing aircraft
      based on the popular SkywalkerX8 hobby
      drone. These have longer ranges than
      quadcopters and can carrybigger pay-
      loads. Other groups in Syria, and in Iraq as
      well, employ similar devices. Their use has
      spread, too, to non-politically-motivated
      criminals. In October, four Mexicans alleg-
      edly linked to a drug cartel were arrested
      with a bomb-carrying drone.

Cheap shots

Compared with military hardware, drone

technology is both readily available and

cheap. In 2014 a team atMITRE, a security

think-tank based in Virginia, made a mili-

tary-grade drone using commercial elec-

tronics, a 3D-printed airframe and open-

source software. It cost $2,000. A whole

squadron of such craft could thus be as-

Drones and guerrilla warfare

Buzz, buzz, you’re dead

Home-made and home-modified drones are now a threat to conventional

armies and navies

Science and technology

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