SLOVIANSK, Ukraine — An array of mostly unremarkable items stretched across two wooden tables on the far side of a cramped workshop in eastern Ukraine: double-sided tape, gloves, Allen wrenches, a soldering iron, 3-D printed plastic, ball bearings, a digital scale. Next to them was a German DM51 fragmentation grenade.
They were all important ingredients for Ukrainian troops trying to piece together a puzzle: How do you create a grenade that weighs next to nothing but can be dropped from a drone and destroy a roughly 40-ton Russian tank?
“War is an economy. It’s money,” said Graf, a stout, bearded Ukrainian soldier in charge of his unit’s drone team. “And if you have a drone for $3,000 and a grenade for $200, and you destroy a tank that costs $3 million, it’s very interesting.”
Since Russia launched a full-scale invasion of Ukraine nearly a year ago, technological advancements on the battlefield have mostly centered on both countries’ increased use of small, remotely operated drones and their growing importance in almost every aspect of the war — including reconnaissance, correcting artillery fire and so-called kamikaze attacks.
Now Graf and his team, who have become experts at killing Russian troops with munitions dropped from the air, are trying to raise the drones’ effectiveness to the next level: by using them to deliver what they consider the perfect grenade.
The challenge is building that grenade.
“It’s our main goal,” Graf said last month from his headquarters in the city of Sloviansk. He was surrounded by the various components needed to turn a flying toy into a lethal battlefield tool. Like other Ukrainian soldiers during the war, he identified himself to reporters only by his military call sign.
The tinkering in Graf’s workroom is another example of how Ukraine’s military has adapted as the war progresses, creating advantages in the face of the Russian Army’s superiority in troop numbers and long-range weaponry.
The grenade, Graf said, should weigh around 1.1 pounds, the maximum weight a DJI Mavic 3 drone can carry without its flight being significantly disrupted.
To get the grenade closer to the desired weight, his team has been using a 3-D printer to try to make a lightweight casing that can hold the explosives needed to penetrate a tank’s armor. The painstaking task involves experimenting with grenades of differing designs, clasped in a vise in their workroom, and operating around the explosive mechanisms to fine-tune them.
The grenade should be able to penetrate the hull of an armored personnel carrier or tank, something not currently possible with a munition weighing around a pound, Graf said. For now, their best grenade is the German-supplied DM51, an explosive that, with stabilizing fins attached, weighs near their imposed threshold.
But the DM51 is manufactured to kill people, and is not effective against a tank.
“Every day, we study, we make some experiments with grenades, with bombs, with drones, and make our work better,” Graf added.
To Graf and the legions of Ukrainian drone operators and armorers, the quest for an enhanced grenade is part of a broader drone arms race with Russia. Like Graf’s team, the Russian military is also trying to make its small unmanned vehicles deadlier, to varying levels of success.
The Chinese-made Mavic 3 drone has turned into the ubiquitous backbone of Ukraine’s drone forces. It is small, portable, has a decent battery life and range and can quickly be outfitted to drop grenades. Russian forces use it, too.
The Russians’ bigger military drones, like the self-exploding Shahed-136, which is made in Iran and frequently launched at Ukraine’s infrastructure, are used differently from the small Mavics that are deployed against concentrations of troops and trenches. The Mavics are quadcopters — they can hover like a helicopter directly over their target before dropping their lethal cargo.
Ukraine has stayed ahead in the drones arm race in much the same way as it has succeeded on the battlefield: Lower-level commanders have more leeway in how and when to use them, and drone units like Graf’s have less bureaucracy to navigate to test and deploy their weapons.
“The Ukrainian drone effort is more streamlined and works directly with the military,” said Samuel Bendett, a specialist on Russian drones and other weapons at CNA, a research and analysis organization in Arlington, Va. “The Russians are only getting there now.”
That means that Graf and his comrades’ inventions can quickly be shared with other drone units in chat groups before being used in the field, with little oversight.
Russia, Mr. Bendett said, has taken a more industrial approach to the drone arms race, preferring munitions that are mass produced, though some Russian volunteer groups are making progress in testing and sending drones to the front line. The only drawback for the Russians: navigating Moscow’s Soviet-era bureaucracy to get the right equipment into their soldiers’ hands, Mr. Bendett said.
“There’s a lot of this back-and-forth,” he said. “One side has a tech breakthrough, and the other side catches up.”
Tucked away on one of the shelves in Graf’s workshop was evidence of Moscow’s industrialized attempts to compete with Kyiv: a factory-produced Russian OFSP, a small, roughly 40-millimeter grenade meant to be dropped by an Orlan-10, a reconnaissance drone that sounds like a lawn mower. The grenade had a manufacture date of March 2022 stenciled onto its side.
“They are just dropping a default modification of this grenade,” said Iliya, one of Graf’s drone engineers and armorers. “We are dropping everything that we can find.” The main thing to consider, he said, “is the weight of a grenade that the drone can move.”
Another obstacle that Ukrainian drone operators face is having to modify the weapons to work in ways that they were not originally built to.
The challenges are twofold: Inundated with munitions from countries like France, Germany and the United States, Ukrainian troops need to learn the intricacies of each device before jury-rigging the explosives.
That process is complicated, too. Some small grenades like the M433, which is made and supplied by the United States — and is sometimes called the Golden Egg because of its size, shape and color — have the kind of shaped-charge warhead that can punch through armor plate. But they are meant to be fired only from hand-held grenade launchers, and not dropped by drones.
So Ukrainian soldiers must carefully place the grenade into a vise grip, pry off the cartridge case that contains the propellant used to fire it and then begin the even more delicate work of teasing off the aluminum cup over the grenade’s nose. With pliers and other hand tools, the soldiers must gently probe and manipulate the fuze’s inner mechanisms to disable both of its safety features. If successful, they are left with a grenade that could easily explode if mishandled.
And before it can be sent on a mission against Russian troops, the explosive has to be carefully mounted onto the drone.
Graf said that no one on his team had been killed while working on the grenades, but that the process was perilous for troops on the front line. There are “many, many dead guys because they don’t understand how these things work,” he said.
Despite the risks, Graf and his team continue to tinker in their workshop teeming with different kinds of explosives, edging ever closer to the elusive tank-killing grenade. Currently, they have a munition that they say can penetrate Russian armor, but it is around a half-pound too heavy.
“We make grenades from the trash,” joked Graf. “But if you can destroy a tank from a Mavic, you’re the best at this war.”
John Ismay contributed reporting from Washington.