« It is virtually impossible to defend against drones »

It was the United States, in the early 2000s, that star­ted using drones to elim­in­ate ter­ror­ist tar­gets in the tri­bal areas of Pakistan and Afgh­anistan. At the time, they were big machines. They looked like fight­er jets, flew high and could not be oper­ated by civil­ians or ter­ror­ists. But those days are gone for good.

Yes, they are now being used more and more for civil­ian applic­a­tions, which is very inter­est­ing. For example, farm­ers can use small, inex­pens­ive drones (cost­ing from €600) to spread fer­til­iser equally over fields. The prob­lem? These are the same drones that will be bought by drug traf­fick­ers or ter­ror­ist groups, diver­ted from their inten­ded use. Mex­ic­an car­tels, for example, buy agri­cul­tur­al drones and replace weedkiller spray­ers with the same weight of gren­ades weigh­ing around 10–20 kg. These days, it’s almost as easy to make your own drone kit as it is to assemble a piece of Ikea fur­niture! You can also adapt it to your par­tic­u­lar needs, with a bat­tery that lasts longer or short­er, a cam­era of vary­ing res­ol­u­tion, and a vari­able con­trol dis­tance. In short, there’s some­thing for every pur­pose and every price…

They are now used in all con­flicts, but they are par­tic­u­larly use­ful in cer­tain con­fig­ur­a­tions. In the war against Hamas, the Israel­is can use them to get inside tun­nels. If they were only to send men to these loc­a­tions, the loss of life would be much higher.

Yes. The prob­lem with drones is that they are very easy and inex­pens­ive. Also, it’s very com­plic­ated, if not impossible in some con­fig­ur­a­tions, to defend against them. For “simple” attacks involving a lim­ited num­ber of drones, there are, of course, sys­tems for detect­ing the intru­sion of a drone into a pro­tec­ted area (air­port, sta­di­um, etc.), then jam­ming its nav­ig­a­tion sys­tem, or des­troy­ing the air­craft. How­ever, cer­tain so-called “swarm” attacks, which involve send­ing sev­er­al dozen – or even sev­er­al hun­dred – drones in mul­tiple dir­ec­tions, are vir­tu­ally unstop­pable. Bey­ond thirty drones, it becomes com­plic­ated to defend oneself.

Yes, I’m in charge of the sci­entif­ic com­mit­tee of the first European fed­er­a­tion of secur­ity drones, DRONES4SEC, launched in 2021.We are work­ing on anti-drone mod­el­ling. For example, in a swarm attack con­fig­ur­a­tion, we are try­ing to cal­cu­late how many drones need to be launched at the same time, at what speed, along what tra­ject­or­ies and to neut­ral­ise as many hos­tile vec­tors as pos­sible. A tech­no­lo­gic­al plat­form will be developed for this purpose.

In addi­tion, at European level, we are work­ing with PARROT (Europe’s lead­ing drone man­u­fac­turer) on a ‘trus­ted drone’ label, which would guar­an­tee drone buy­ers that their flight data and per­son­al data will not be exfiltrated each time they use a drone. Some drone man­u­fac­tur­ers, par­tic­u­larly Chinese ones, have major prob­lems with respect for per­son­al data. In fact, the main Chinese drone man­u­fac­turer, the world lead­er in the sec­tor, is now banned from selling to secur­ity forces in North Amer­ica for this very reason.

Tur­key, India, Iran, and Israel are all very act­ive in the pro­duc­tion of civil­ian and mil­it­ary drones. While nuc­le­ar weapons are still reserved for a very select club of major powers, drones are on the way to becom­ing “the poor man’s weapon”. Fixed-wing drones car­ry­ing 2–3 kg of explos­ives are used as kami­kaze drones against all kinds of high-value tar­gets: armoured vehicles, tanks, artil­lery, sup­ply trucks, radar, and com­mu­nic­a­tions sys­tems. These prowl­ing muni­tions rep­res­ent a minor revolu­tion in the “art of war”. With very low pro­duc­tion costs and almost infin­ite mul­ti­plic­a­tion pos­sib­il­it­ies, these muni­tions can be used to des­troy highly tac­tic­al tar­gets on the enemy’s side, which are often very costly. The destruc­tion ratio (i.e. the cost of the prowl­ing muni­tion versus the cost of the tar­get) clearly favours the attack­er and forces the attacked to deploy soph­ist­ic­ated and costly means of protection.

Yes. An aer­i­al drone ded­ic­ated to intel­li­gence can remain in the air for 24 hours, without a pilot on board, while car­ry­ing out its data-gath­er­ing mis­sion. Oth­ers are designed for com­bat or artil­lery guid­ance. Quad­copter micro-UAVs (with four pro­pellers) are used by the Rus­si­an and Ukrain­i­an armies to “clear” a trench by drop­ping gren­ades ver­tic­ally on the tar­geted fight­ers, with cen­ti­metre accur­acy. These drones are often com­mer­cial indus­tri­al drones trans­formed into gren­ade launch­ers, using a rudi­ment­ary charge-car­ry­ing system.

Some can oper­ate in fully auto­mat­ic mode, car­ry­ing out a mis­sion on a tar­get on their own and return­ing. Oth­er machines must always be under the con­trol of a remote pilot, from a great­er or less­er dis­tance. Above all, there are drones for every envir­on­ment: the air, but also land, sea, and even under­wa­ter robots! The Turks recently demon­strated three drone launches on the sur­face of the water, painted blue so they could­n’t be spot­ted. They man­aged to cut the hull of a cargo ship in half at sea! It was only a test, but it gives you an idea of the power of these machines…

The “Black Hor­net” is a micro recon­nais­sance drone that looks like a heli­copter, but meas­ures just 10 cm and weighs 30 g. The Amer­ic­ans sell it for €40,000 but the Chinese have just put an inspired ver­sion on the mar­ket for 130 dol­lars! For this price, it weighs just 20g more than the ori­gin­al, is barely any big­ger, and offers almost the same per­form­ance… The fall in the price of civil­ian drones and robots will lead to their wide­spread use in all areas of activity. 

There are more and more of them. Dur­ing the last earth­quake in Morocco, drones were sent inside build­ings that were still stand­ing to spot cracks and identi­fy which could be saved and which could not. After the storms in France, some roof­ers used drones to spot miss­ing tiles on roofs and inter­vene dir­ectly where necessary.

Interview by Marina Julienne