The following is the Aug. 25, 2023, Congressional Research Service Report, Navy Large Unmanned Surface and Undersea Vehicles: Background and Issues for Congress.
From the report
Among the Navy’s programs for developing and acquiring unmanned surface vehicles (USVs) and unmanned underwater vehicles (UUVs) of various sizes are programs for developing two large USVs—the Large Unmanned Surface Vehicle (LUSV) and Medium Unmanned Surface Vehicle (MUSV)—and a program for a large UUV called the Extra-Large Unmanned Undersea Vehicle (XLUUV). The Navy wants to develop and acquire LUSVs, MUSVs, and XLUUVs as part of an effort to shift the Navy to a more distributed fleet architecture, meaning a mix of ships that spreads the Navy’s capabilities over an increased number of platforms and avoids concentrating a large portion of the fleet’s overall capability into a relatively small number of high-value ships (i.e., a mix of ships that avoids “putting too many eggs into one basket”). The Navy’s proposed FY2024 budget requests $117.4 million in research and development (R&D) funding for the LUSV program, $85.8 million in R&D funding for the MUSV program, $176.3 million in R&D funding for LUSV/MUSV enabling capabilities, $104.3 million in R&D funding for the XLUUV program, and $71.2 million in additional R&D funding for core technologies for UUVs including but not limited to XLUUV.
LUSV. The Navy envisions LUSVs as being 200 feet to 300 feet in length and having full load displacements of 1,000 tons to 2,000 tons, which would make them the size of a corvette. (i.e., a ship larger than a patrol craft and smaller than a frigate). The Navy wants LUSVs to be low-cost, high-endurance, reconfigurable ships with ample capacity for carrying various modular payloads—particularly anti-surface warfare (ASuW) and strike payloads, meaning principally anti-ship and land-attack missiles. Each LUSV could be equipped with a vertical launch system (VLS) with 16 to 32 missile-launching tubes. Although referred to as unmanned vehicles, LUSVs might be more accurately described as optionally or lightly manned ships, because they might sometimes have a few onboard crew members, particularly in the nearer term as the Navy works out LUSV enabling technologies and operational concepts. The Navy has been using LUSV prototypes to develop LUSV operational concepts. The Navy’s FY2024 budget submission programs the procurement of production LUSVs through the Navy’s shipbuilding account, with the first LUSV to be procured in FY2025 at a cost of $315.0 million, the next two in FY2026 at a combined cost of $522.5 million (i.e., an average of about $261.3 million each), the next three in FY2027 at a combined cost of $722.7 million (i.e., an average of $240.9 million each), and another three in FY2028 at a combined cost of $737.2 million (i.e., an average of about $245.7 million each).
MUSV. The Navy defines MUSVs as being 45 feet to 190 feet long, with displacements of roughly 500 tons, which would make them the size of a patrol craft. The Navy wants MUSVs, like LUSVs, to be low-cost, high-endurance, reconfigurable ships that can accommodate various payloads. Initial payloads for MUSVs are to be intelligence, surveillance, and reconnaissance (ISR) payloads and electronic warfare (EW) systems. The Navy’s FY2024 budget submission states: “While there are no MUSV[s] funded [for procurement] in the FY 2024-FY 2028 FYDP [Future Years Defense Program], the structure of the [MUSV] contract awarded to L3 Harris in July 2020 allows for [procurement] options to be added should funding become available. Delivery of the initial [MUSV] prototype is planned in Q4 [i.e., the fourth quarter of] FY 2024 followed by Developmental and Operational Testing. The prototyping efforts with the FY 2019 MUSV will inform procurement of additional MUSV units and transition to an ACAT [Acquisition Category] program with formalized requirements through a Capability Development Document [CDD] and procurement funding as part of a decision in future budgets.”
XLUUV. XLUUVs are roughly the size of a subway car. The Navy wants to use XLUUVs to, among other things, covertly deploy the Hammerhead mine, a planned mine that would be tethered to the seabed and armed with an antisubmarine torpedo, broadly similar to the Navy’s Cold War-era CAPTOR (encapsulated torpedo) mine. Five “operationally relevant prototype” XLUUVs were procured in FY2019. An additional XLUUV test and training asset has also been procured. The Navy’s FY2024 budget submission programs the procurement of additional XLUUVs through the Other Procurement, Navy (OPN) account, with the one XLUUV to be procured in FY2026 at a cost of $113.3 million, another one in FY2027 at a cost of $115.6 million, and another one in FY2028 at a cost of $117.9 million. The Navy’s FY2024 budget submission states: “Fabrication and award of additional Orca XLUUV systems is planned to be no earlier than FY26. Transition to an Acquisition Category (ACAT) Program and production may occur as early as FY26, pending successful completion of Government testing.”
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