WASHINGTON — The testing of four unmanned surface vessels at the Rim of the Pacific 2022 exercise will help the U.S. Navy kick off a program of record for a large USV in 2025 and help determine if there’s a need for a medium USV in the future hybrid manned-unmanned fleet, program officials said.

Among the three dozen or so ships participating in RIMPAC 2022, which runs through Aug. 4, are four without crews: the large-sized Nomad and Ranger Overlord USVs and the medium-sized Sea Hunter and Sea Hawk.

The international exercise offered a chance to have all four in the water and contributing to a common mission alongside traditional manned warships. Rear Adm. Casey Moton, the program executive officer for unmanned and small combatants, told reporters the USVs proved they were reliable and their autonomy was mature, the payloads proved operationally relevant and the USV Division One sailors operating them proved they were off to a good start in understanding the concept.

Brian Fitzpatrick, the principal assistant program manager for unmanned surface vessels, said the four vessels will have achieved a combined 100-plus days at sea due to RIMPAC and related activities. Feedback received from RIMPAC participants has been entirely about the payloads they carry, not the vessels themselves or autonomy software, he said.

“They’re talking about payloads, they’re talking about capabilities,” he said. “They’re not worried that it’s going to go run into something.”

All the fleet feedback from RIMPAC will go into an iterative test and experimentation process. It will also help inform decisions the Navy will have to make in the leadup to buying the first program-of-record Large USV in fiscal 2025.

To meet that timeline, established in the FY23 budget request, Moton said the program office is heavily focused on getting to the right level of technical maturity and having several key technology areas certified, including the machinery plant and other systems going through rigorous land-based testing.

“At its most fundamental level, the program office is using [RIMPAC] as a sort of piece of its plan to get to those certification points and that transition to LUSV,” he said, noting that the hours at sea are another data point on system performance and reliability.

A program of record needs more than just a technical design, Moton said. It needs a mature understanding of the manning, training, maintenance, logistics, concepts of operations and more that will make the program successful once fielded — and that’s where USV participation in RIMPAC is especially valuable.

The future of the medium USV remains unclear, after Chief of Naval Operations Adm. Mike Gilday said this spring that advances in testing smaller USVs in larger quantities had proven successful and may be cheaper than fielding MUSVs.

Moton said some lessons learned from Sea Hunter and Sea Hawk, particularly on autonomy and reliability, are transferrable to the LUSV program of record and would inform that effort.

“Whether or not we will buy more MUSVs will be certainly informed by what we’re learning at RIMPAC,” he said, adding that a “completely healthy conversation” is happening within the Navy and with industry about whether an MUSV would be value-added to the future fleet.

Moton said the Pentagon hadn’t made decisions yet on which payloads to invest in, so feedback from RIMPAC participants would be shared with Navy resource sponsors and with the research and development community to inform their prioritization of funds.

Fitzpatrick said four separate payloads are being used on the four USVs, and they’re largely based on existing sensors and processors that exist within the Navy inventory and could be altered to be compatible with an unmanned vessel. Sea Hawk, for example, is carrying a towed array sonar, which the Navy had to alter so it could unreel itself into the water during USV operations.

Capt. Scot Searles, the unmanned maritime systems program manager, told reporters that RIMPAC was — for both the unmanned vessel itself and for the payloads — providing both performance data as well as a look at “is the fleet using it the way we thought they would, and is it effective in its use?”

Ultimately, he said, the program office wants to “make sure the capability is going to answer what the call was for in the first place.”

In that respect, the medium and large USVs within Searles’ portfolio are quite different than another USV Moton and PEO USC have been developing.

Whereas MUSV and LUSV are meant to be trucks that could employ a range of payloads — sensors, jammers, even missiles down the road — the Navy just declared initial operational capability for the Unmanned Influence Sweep System within the Littoral Combat Ship’s mine countermeasures mission package.

“UISS is the first USV that we’ve IOCed,” Moton said during the roundtable. “It’s the first unmanned craft there. Clearly it’s got a different mission: it’s under local control of the asset that it’s operating from, whether it’s an LCS or a vessel of opportunity or the pier. So it’s a different autonomy problem, it’s executing a mine warfare mission” in a traditional sweep pattern and not straying too far from its host platform, he said.

Reaching that milestone for any USV is important in building trust and confidence in the unmanned systems that will be so important to the future fleet, he said.

“This craft, having it IOC, which means it’s through test, which means we have numbers fielded, which means we have trained crews, which means we have logistics set up … It’s just a huge milestone to get that done for our first surface MCM platform,” Moton said.

Megan Eckstein is the naval warfare reporter at Defense News. She has covered military news since 2009, with a focus on U.S. Navy and Marine Corps operations, acquisition programs and budgets. She has reported from four geographic fleets and is happiest when she’s filing stories from a ship. Megan is a University of Maryland alumna.

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