USX-1 Defiant

The USX-1 Defiant is a unmanned warship built as a demonstration project by the Defense Advanced Research Projects Agency (DARPA) and completed in February 2025^[2][3] and began sea trials in following month. It was first seen in public in March 2025 near the U.S. Navy's Naval Air Station (NAS) Whidbey Island.^[4] The ship has an LOA (length overall) of 180 feet with a 240 metric ton displacement.^[5] Defence Shipbuilder Serco oversaw the project.^[6]

USX-1 Defiant shortly after launching

History
United States
Builder	Nichols Brothers Boat Builders Serco Maritime
Christened	11 August 2025[1]
General characteristics
Displacement	240 metric tons
Length	180 feet (55 m)
Speed	20 kts
Complement	0

During sea trials at Port Hueneme, California, the NOMARS validated apabilities of the Defiant, including successful demonstration of automated at-sea fueling. The USX-1 Defiant also tested high-speed turns and speed tests at up to 20 knots. Defiant also achieved automated dockings, undockings and harbor entry and exit.^[7]