A robotic combined arms breach carried out during a US Army exercise in April cleared an enemy-held position using attack drones and C4-laden ground robots before a single rifleman stepped into the fight. The operation, conducted by the 101st Airborne Division’s 3rd Mobile Brigade Combat Team at the Joint Readiness Training Center (JRTC) in Louisiana, showed how uncrewed systems could reshape one of the most dangerous tasks in ground combat.
What a Robotic Combined Arms Breach Actually Looks Like
Breaching is a slow, lethal mission. Soldiers must pick through mines, wire, trenches, barriers, and anti-vehicle ditches while enemy forces train machine guns, artillery, and mortars on the most predictable routes. A unit caught in a chokepoint can be destroyed in minutes.
Col. Ryan Bell, the brigade commander, gave one of his company commanders a clear directive: make the breach uncontested before the riflemen arrived. The commander’s answer was to launch 25 purpose-built attritable systems (PBAS) drones, not generic commercial hardware, that soldiers had assembled themselves using parts from the Blue UAS Cleared List and 3D-printed components. According to Breaking Defense, the formal military term for this type of operation is a robotic combined arms breach, where uncrewed ground and aerial vehicles defeat enemy defences before troops advance.
The drones struck bunkers, machine gun nests, and triple-strand concertina wire. Separate systems targeted electronic warfare sensors and jammers, while others dropped smoke canisters to obscure the battlefield. Then two uncrewed ground vehicles packed with C4 explosives destroyed the remaining land mines and wire obstacles. One of those vehicles was a Hunter Wolf Unmanned Ground Vehicle (UGV), operated by soldiers from the 3rd Mobile Brigade during the training on 13 April 2026.
‘When the riflemen got there, the breach was uncontested,’ Bell said. ‘Every target had been struck.’
Bell put a cost on the approach: 35 drones and just over 100 pounds of C4, which he said came in under the cost of three 155mm artillery barrages. ‘And you didn’t have an engineer or a Sapper squad running out with a grappling hook trying to low-crawl with a Bangalore torpedo,’ he added.
The Drone Contact Layer and Its Limits
Bell described the underlying concept as a ‘drone contact layer’: uncrewed systems that engage the enemy first, so that when soldiers arrive the fight is already decided in their favour. ‘When my riflemen get there, the enemy is already down, and they are finishing the fight, but it’s an unfair fight,’ he said.
The brigade’s drone experimentation extended beyond the breach itself. Soldiers assembled their own cheap, attritable systems from parts on the US Army‘s Blue UAS Cleared List. Bell’s key lesson from the exercise was the need for large numbers of such systems that troops can deploy quickly in combat conditions.
The Blue UAS Cleared List itself recently changed hands. Management of the programme transitioned in late 2025 from the Defense Innovation Unit to the Defense Contract Management Agency (DCMA), with DCMA’s Special Programs office now running the Blue List portal, according to Morgan Lewis.
Artificial intelligence also featured in the exercise at Fort Johnson, though Bell was clear about where it helped and where it did not. An AI system processed 25,000 battlefield reports to give commanders a clearer picture of the operating environment. But when it came to planning courses of action, large language models fell short. ‘Large language models don’t really understand three-dimensional space, so they’re not good for developing courses of action,’ Bell said. ‘That’s where you need the expertise of a skilled staff to understand the art of fighting to plan the operation.’
Bell framed the broader lesson in terms that cut against an over-reliance on any single technology. ‘The focus of the training has got to be on the fundamentals of warfighting,’ he said, stressing that technology should function as an enabler rather than a replacement for soldiering skills.
The robotic combined arms breach will now face a harder test: replicating the conditions of a contested, degraded environment where an adversary is actively jamming drone signals and targeting the uncrewed systems before they reach the wire.