NOMARS' Defiant USV is conducting in-water testing ahead of an at-sea demonstration. | Source: Serco North America
Summary
The No Manning Required Ship (NOMARS) program has built a ship designed to operate autonomously for long durations at sea – the unmanned surface vessel (USV), USX-1 Defiant. As of summer 2025, the 180', 240-metric-ton lightship is undergoing in-water testing to prepare for an extended at-sea demonstration of reliability and endurance.
The NOMARS program aims to challenge the traditional naval architecture model, designing a seaframe (the ship without mission systems) from the ground up with no provision, allowance, or expectation for humans on board. By removing the human element from all ship design considerations, the program intends to demonstrate significant advantages, to include: size, cost, at-sea reliability, greater hydrodynamic efficiency, survivability to sea-state, and survivability to adversary actions through stealth considerations and tampering resistance.
With scaled production, NOMARS has the potential to efficiently and cost-effectively deliver a distributed USV fleet.
Office
Tactical Technology Office
