Britain hands Ukraine the blueprints for Stone Cloak, not just the jammers
London signed over the intellectual property for its Stone Cloak drone jammer so Kyiv can build it at scale, a shift from donating finished weapons to donating designs.
London signed over the intellectual property for its Stone Cloak drone jammer so Kyiv can build it at scale, a shift from donating finished weapons to donating designs.
Britain has signed over the intellectual property for Stone Cloak, a tablet-sized digital jammer flown on Ukrainian long-range strike drones, letting Ukraine mass produce the device domestically, Defense One reported on Wednesday.
The unit degrades Russian air defence tracking as a drone runs in on its target. The Ministry of Defence has already shipped thousands of British-built ones to Ukrainian forces, the Telegraph wrote. London disclosed the programme on Saturday, when Volodymyr Zelensky met Prime Minister Andy Burnham at Portsmouth during the Sea Breeze exercise. Burnham called Stone Cloak "the best of homegrown British innovation, and proven on the frontline."
Britain supplied Storm Shadow cruise missiles from 2023 and kept the drawings. That missile took six years to field and averaged $2 million a round, per Defense One, and its French and Italian supply chains made a transfer bureaucratically difficult.
The battlefield and the startup story — free in your inbox every week. No paywall.
Subscribe Free →UK forces will now collect performance data from Ukrainian combat use and apply it to the next generation of British drones and missiles, including Project Brakestop, the low-cost cruise missile the two countries began developing jointly in 2024, Euractiv noted. Officials expect Brakestop at the front later this year, inside 24 months from concept.
Ukrainian units field battlefield lessons in under 10 days, Jeffrey Fischer, a retired US Air Force officer, told Defense One. "In my seven combat deployments, NOTHING has ever come close to that." Fischer added that Stone Cloak's full specifications are not public, but that the system will likely improve mission effectiveness against some Russian air defences.
Brakestop reaches the front later this year, with Stone Cloak slated for integration into it.
Frequently Asked Questions
What is Stone Cloak?
A small digital electronic warfare unit, roughly the size of a tablet computer, fitted to Ukrainian strike drones to stop Russian air defence systems tracking and targeting them, according to the UK government.
What exactly did the UK give Ukraine?
The intellectual property, not only the hardware. The Ministry of Defence had already supplied thousands of British-built units; the new agreement lets Ukraine manufacture the system domestically at scale, the Telegraph reported.
Why is transferring the design unusual?
Britain supplied Storm Shadow cruise missiles from 2023 but never handed over the design technology. Defense One noted the missile took six years to develop, averaged about $2 million each, and depended on French and Italian supply chains that complicated any transfer.
What does Britain get out of it?
Officials said UK forces will gather performance data from Ukrainian combat use and apply it to the next generation of British drones and missiles, including Project Brakestop, a low-cost cruise missile programme run jointly with Ukraine since 2024.
Do we know how well Stone Cloak works?
Not in detail. Jeffrey Fischer, a retired US Air Force officer, told Defense One that the full specifications are not public, but that the system will likely improve mission effectiveness against some Russian air defences.
AI-generated summary, reviewed by an editor. More on our AI guidelines.
Marcus Schuler
Marcus Schuler edits BattlePolicy, a daily defense-technology brief connecting the companies and capabilities behind modern war to the contest among Europe, the US, Russia, and China.