Buzzing like an oversize mosquito, a small drone lifted off from a farm field in eastern Ukraine, hovered for a bit, then raced toward Russian positions near the battle-ravaged city of Bakhmut.
“Friends, let’s go!” said the pilot, Private Yevhen. With a pair of virtual reality goggles strapped around his head, he used joysticks to steer the craft and its payload of two pounds of explosives.
Cobbled together from hobby drones, consumer electronics and computer gaming gear, handmade attack drones like this one have emerged as one of the deadliest and most widespread innovations in more than 14 months of warfare in Ukraine.
Along the front line, drones extend the reach of soldiers, who can fly them with pinpoint accuracy to drop hand grenades into enemy trenches or bunkers, or fly into targets to blow up on impact. Self-destructing drones, in particular, are easily constructed, and thousands of soldiers on both sides now have experience building them from commonly available parts — though the Ukrainians say they use such weapons more frequently than their Russian opponents.
These small craft proliferated on the battlefield last fall, long before Russia said on Wednesday that two explosions over the Kremlin were a drone strike. Kyiv and Moscow have blamed each other for the incident, and if attack drones did, in fact, fly over the Kremlin walls, it is unclear what type they were, what kind of range they had, or who was responsible.
For years, the United States deployed Predator and Reaper drones in Iraq and Afghanistan that cost tens of millions of dollars apiece, and can fire missiles and then return to their bases. Ukraine, in contrast, has adapted a wide array of small craft that are widely available as consumer products, from quadcopters to fixed-wing drones, to spot artillery targets and drop grenades.
Exploding drones belong to a class of weapons known as loitering munitions, for being able to circle or hover before diving down on a target.
Russia manufactures a self-destructing drone specifically for military use, the Lancet, and it has made extensive use of Shahed attack drones bought from Iran. The United States has provided to the Ukrainian military a purpose-built loitering munition, the Switchblade.
Such industrially made craft have longer ranges and some have heavier payloads than the homemade weapons used in Ukraine. But the Switchblade, like the Shahed, often navigates to preprogrammed targets, a system that Ukrainian soldiers say is less effective than their hand-built alternatives, steered remotely by operators.
Soldiers and civilian volunteers make these in garage workshops, experimenting and inventing with 3-D printed materials, explosives and custom-built software to try to avoid Russian electronic countermeasures.
They have produced some drones that drop bombs large enough to destroy armored vehicles and can be reused, and cost as much as $20,000.
The smaller, more common self-destructing drones like those flown by Private Yevhen cost a few hundred dollars. They are built around a type of drone used for hobby racing, usually a model made by the Chinese company DJI, with explosives attached using zip ties or tape. They are single-use, disposable weapons; once armed and launched, they cannot even be landed safely.
“I see huge potential” for the weapon in the type of trench fighting that has dominated the war, Maj. Kyryl Veres, the commander of a Ukrainian brigade stationed near Severesk, to the north of Bakhmut, said in an interview. “Any equipment can be hit in a place where the enemy thinks he is a million percent safe.”
A cheap drone destroying a far more expensive armored personnel carrier is a striking example of asymmetric warfare, used to overcome an enemy’s technological or numerical advantages. And despite the influx of Western weapons, Ukrainian forces remain outgunned by the Russians.
“The Ukrainian army should use unusual, asymmetrical tools of war,” said Serhiy Hrabsky, a retired army colonel and commentator on the war for Ukrainian media.
He drew a parallel to the roadside bombs that insurgents in Iraq and Afghanistan used, to devastating effect, against the U.S. military, which called them improvised explosive devices. Ukraine, Colonel Hrabsky said, is using “improvised kamikaze drones.”
He added that “the art of war is not static.”
The experience of flying with virtual reality goggles, providing an immersive view from the drone’s camera, is like playing a high-stress video game. The missions are far from risk-free for the pilots. The short range of the drones while carrying explosive loads — about four miles, typically — means the pilots must fly from trenches at or near the front line, where they are vulnerable to artillery and snipers.
Still, the drones are lethally effective. The Ukrainian military has posted dozens of videos recorded by the drones as they swoop in on targets, with devastating accuracy.
Pilots chase and hit moving tanks or fly through the open doors of armored vehicles to explode inside, as soldiers at the last moment try to jump to safety. And they routinely fly drones into bunkers, which was the intention of Private Yevhen, who was stationed near a front line in the battle for Bakhmut.
On a recent, crystalline spring morning, the thicket of trees he operated from was a veritable drone airport: Several units operated surveillance craft while others were seeking to drop hand grenades on Russian trenches.
After the drone took off with a whir, Private Yevhen let it hover for a moment to test the controls. The drone dropped back to earth — a nerve-racking moment, as the explosive was already triggered to detonate. But it did not. He took off again.
If all went according to plan, he would soon see the rapidly approaching entryway to a bunker and at the last moment perhaps a glimpse of doomed Russian soldiers. His hands trembled on the control console.
Two other drones accompanied the attack craft, flying nearby to guide and film the strike. A spaghetti swirl of wires, plugs and screens in a bunker tied the system together.
In the moments after taking off, the pilots called out altitude and the passing of way points on the landscape below.
“Do me a favor and go right,” Private Yevhen told a pilot accompanying him.
The drones reached the critical area where Russian electronic countermeasures could jam their signals, causing pilots to lose control and even crash.
“Stable, stable,” he said of his radio connection. Then Private Yevhen lost control.
“Where did you fly?” he asked his wingman, trying to regain his bearings.
“I’m out here,” the other pilot said.
But Private Yevhen’s exploding drone had gone down several hundred yards short of the target. Neither he nor the accompanying surveillance drones, which were out of position when it went down, could tell if it had exploded or simply settled onto a fields. Whether Russian jamming or a technical flaw had downed the craft was also unclear.
This time, the work of constructing the exploding drone and the risk of getting close enough to launch under artillery fire had resulted only in lessons learned, not a successful strike.
“All is lost,” he said, taking off his goggles. “It just fell down.”
Maria Varenikova contributed reporting from Ivaniske, Ukraine.