How Drone Swarms Work—From Iran’s Shahed Attack to Ukraine’s Operation Spiderweb

How Drone Swarms Work—From Iran’s Shahed Attack to Ukraine’s Operation Spiderweb

By Deni Ellis Béchard edited by Dean Visser

Six hours after Israel’s air strikes in Iran last Friday, farmers in Iraq could have looked up and seen Iranian drones traveling west: more than 100 of them flew on a 1,700-kilometer journey to Israel, with their propellers buzzing like Weedwackers. Among them was the Shahed-136. Composed mostly of foam and plywood, each Shahed-136 drone is 3.5 meters long and has a 2.5-meter wingspan and a 40- to 50-kilogram warhead at its nose. The drone’s “brain,” a sensor the size of a cough drop, measures every movement while a credit-card-sized GPS onboard listens for microwave chirps from navigation satellites. The Shahed’s route (its waypoints in latitude, longitude and altitude) is uploaded before a booster rocket fires it into the sky. And it is loud: its 50-horsepower motor is slightly more potent than that of a 1960s Volkswagen Beetle and would be as noisy as a lawn mower or a moped at full throttle—now multiplied by 100 in what military strategists sometimes refer to as a rudimentary swarm.

Drone swarms can take different forms. In attacks such as Iran’s recent launch of drones at Israel—or Russia’s use of them against Ukraine, where Shahed drones are nicknamed “flying mopeds”—the swarm’s power is in its numbers. One missile with a similar range can cost upward of $1 million, but a Shahed can be knocked together for $20,000 to $50,000. Iran’s Islamic Revolutionary Guard Corps (IRGC) fires them from portable rails or from racks on trucks, and the small pulse rocket on the bottom of each drone slams it to cruise speed before falling off. The Center for Strategic and International Studies describes such drone salvos as tools “used as much to saturate air defenses as they are to attack targets, cluttering radar screens and forcing command centers to make decisions about where to fire their more capable surface-to-air missiles,” exactly the situation Israel faced.

Last Friday, as the more than 100 Iranian drones flocked toward Tel Aviv and were shot down by fighter jets, Israel’s Iron Dome air defense system and a U.S. Navy destroyer in the Mediterranean, they couldn’t adjust…