Maritime

Defiant tests a ship designed for no crew aboard

Sea trials · March 27, 2026

USX-1 Defiant unmanned surface vessel underway near a container port. — USX-1 Defiant during autonomy and control-software testing off Long Beach, California, March 2026. DARPA / DVIDS · Public domain (U.S. government work; DVIDS) · Resized and converted to WebP. The appearance of U.S. Department of War (DoW) visual information does not imply or constitute DoW endorsement.

DARPA’s NOMARS program built USX-1 Defiant as a demonstrator with no accommodation for a crew. Its program update describes reliability work through winter 2025–2026, a return to the water in February, and acceptance trials for navigation and machinery-control software improvements.

Earlier demonstrations included autonomous docking and a replenishment exercise that transferred water in place of fuel without anyone aboard Defiant. These are test milestones. They do not establish that the program has completed every long-duration endurance objective or that the ship represents a deployed operational fleet.

Source checked September 24, 2026. Status describes the linked record, not an assumption about later progress.