A Built From Scratch To Be Fully Autonomous U.S. Navy Drone Ship

While it is still experimental, a prototype 180 foot long, 240 ton, U.S. Navy drone ship, built from the bottom up to be a drone rather than retrofitted from a manned vessel, would operate without human involvement for up to a year, could refuel autonomously, and would carry 4 naval missiles, while a larger version would carry 16 of them. The prototype has now been launched for sea trials. 

It would be interesting to know just how much larger an equivalent manned vessel would be.

Serco launched the Defense Advanced Research Projects Agency’s No Manning Required Ship program medium unmanned surface vessel prototype, USX-1 Defiant, at Nichols Brothers Boat Builders shipyard last month in preparation for a series of trials that aim to bring a cost-effective USV to the U.S. Navy.

From the design’s outset, the 180-foot-long, 240-ton vessel was designed without considering human habitation or protection features. According to DARPA, the NOMARS program “intends to demonstrate significant advantages,” including at-sea reliability, hydrodynamic efficiency, and stealthy features.

“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,” stated the DARPA release.

Serco was selected to construct the demonstrator by DARPA over Leidos Gibbs and Cox in 2022. The program, originally launched in 2020, looks to design a Medium USV with unprecedented reliability and availability.

Ryan Maatta, a Marine Engineer Manager with Serco overseeing the NOMARS project, told Naval News at the annual Surface Navy Association symposium that the program’s key features include a 90% reliability at sea for a year and an autonomous refueling capability. USVs Mariner and Ranger demonstrated SERCO’s refueling capability in a test last September. Maatta also confirmed that Defiant would undergo two months of sea trials before “a very large and extensive demonstration of the vessel and its capabilities.” 

The DARPA NOMARS program has successfully launched the USX-1 Defiant, a 180’, 240-metric ton medium unmanned surface vessel designed to revolutionize autonomous operations at sea. DARPA Photo 

While the USV’s deck was covered by a tarp in photos released by DARPA, Serco’s concept models include one BAE Adaptable Deck Launcher and a container. The company’s Large USV concept, which Maatta described as the Second World War-era destroyer escort of the future, comes equipped with four Adaptable Deck Launchers for a complement of 16 strike-length Mark 41 missile cells.

Defiant is unique in this regard, as previously tested USVs such as Nomad and Ranger were retrofitted offshore vessels converted for autonomous operations. Sailors were embarked on the U.S. Navy’s Ghost Fleet Overlord during its 2023 Indo-Pacific voyage to ensure systems ran accordingly. Maatha highlighted that the removal of berths, galleys, and other facilities provides a “much larger payload fraction” on Defiant.