US, UK Navies Launch Torpedo from Unmanned Sub

The US and Royal Navies launched an American Mk 48 heavyweight torpedo from the British XV Excalibur uncrewed submarine on September 13, 2026, at Scotland's Underwater Test & Evaluation Centre. The test, part of Project Broadsword approved seven months earlier, mounted the 3,700-pound weapon externally and validated allied interoperability for autonomous undersea warfare.