Navy Large Unmanned Surface and Undersea
December 19, 2022
Vehicles: Background and Issues for Congress
Ronald O'Rourke
The Navy wants to develop and procure three types of large unmanned vehicles (UVs) called
Specialist in Naval Affairs
Large Unmanned Surface Vehicles (LUSVs), Medium Unmanned Surface Vehicles (MUSVs),

and Extra-Large Unmanned Undersea Vehicles (XLUUVs). The Navy’s proposed FY2023
budget requests $549.3 million in research and development funding for these large UVs and

LUSV/MUSV-enabling technologies, and $60.7 million in additional funding for core
technologies for XLUUV and other Navy UUVs.
The Navy wants to acquire these large UVs 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 and the Department of Defense (DOD) have been working since
2019 to develop a new Navy force-level goal reflecting this new fleet mix. The Navy’s FY2023 30-year (FY2023-FY2052)
shipbuilding plan, released on April 20, 2022, includes a table summarizing the results of studies that have been conducted on
the new force-level goal. These studies outline potential future fleets with 27 to 153 large USVs and 18 to 51 large UUVs.
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 UVs, 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. Under the Navy’s FY2023 five-year (FY2023-FY2027) shipbuilding plan,
procurement of LUSVs through the Navy’s shipbuilding account is programmed to begin in FY2025.
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 FY2023 five-year (FY2023-FY2027) shipbuilding plan
does not include the procurement of any MUSVs during the period FY2023-FY2027.
XLUUVs are roughly the size of a subway car. The first five XLUUVs were funded in FY2019 and are being built by
Boeing. 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. Under the Navy’s FY2023 five-year (FY2023-FY2027) shipbuilding plan,
procurement of additional XLUUVs through the Other Procurement, Navy (OPN) account is scheduled to begin in FY2024.
In marking up the Navy’s proposed FY2020-FY2022 budgets, the congressional defense committees expressed concerns over
whether the Navy’s acquisition strategies provided enough time to adequately develop concepts of operations and key
technologies for these large UVs, particularly the LUSV, and included legislative provisions intended to address these
concerns. In response to these markups, the Navy has restructured its acquisition strategy for the LUSV program so as to
comply with these legislative provisions and provide more time for developing operational concepts and key technologies
before entering into serial production of deployable units.
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Contents
Introduction ..................................................................................................................................... 1
Background ..................................................................................................................................... 1

Navy USVs and UUVs in General ............................................................................................ 1
UVs in the Navy ................................................................................................................. 1
March 2021 Campaign Framework Document for UVs ..................................................... 2
Smaller and Larger Navy USVs and UUVs ........................................................................ 2
Large UVs and Navy Ship Count ....................................................................................... 2
Large UVs as Part of More Distributed Navy Fleet Architecture ....................................... 2
Acquisition Strategies and Enabling Technologies ............................................................. 3
LUSV, MUSV, and LXUUV Programs in Brief ........................................................................ 5
LUSV Program ................................................................................................................... 5
MUSV Program ................................................................................................................ 12
XLUUV Program .............................................................................................................. 15
Issues for Congress ........................................................................................................................ 19
Analytical Basis for Fleet Architecture Including Large UVs ................................................ 19
Concept of Operations (CONOPS) ......................................................................................... 19

Overview ........................................................................................................................... 19
December 2021 Blog Posts ............................................................................................... 19
Navy Efforts to Develop CONOPs ................................................................................... 22
Potential Oversight Questions ........................................................................................... 26
Acquisition Strategies and Technical, Schedule, and Cost Risk ............................................. 26
Overview ........................................................................................................................... 26
April 2022 GAO Report.................................................................................................... 27
Press Reports and Blog Post ............................................................................................. 27

Cost Growth and Schedule Delay in XLUUV Program .......................................................... 32
Industrial Base Implications .................................................................................................... 34
Potential Implications for Miscalculation or Escalation at Sea ............................................... 34

Legislative Activity for FY2023 .................................................................................................... 35
Summary of Congressional Action on FY2023 Funding Request .......................................... 35
FY2023 National Defense Authorization Act (H.R. 7900/S. 4543/H.R. 7776) ...................... 36
House ................................................................................................................................ 36
Senate ................................................................................................................................ 37
House-Senate Agreement .................................................................................................. 37

FY2023 DOD Appropriations Act (H.R. 8236/S. 4663) ......................................................... 37
House ................................................................................................................................ 37
Senate ................................................................................................................................ 37


Figures
Figure 1. Prototypes Supporting the LUSV and MUSV Programs ................................................. 4
Figure 2. Sea Hunter Prototype Medium Displacement USV ......................................................... 5
Figure 3. USV Prototypes ................................................................................................................ 6
Figure 4. LUSV Prototype ............................................................................................................... 6
Figure 5. LUSV Prototype ............................................................................................................... 7
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Figure 6. Rendering of L3Harris Design Concept for MUSV ...................................................... 15
Figure 7. Boeing Echo Voyager UUV ........................................................................................... 17
Figure 8. Boeing Echo Voyager UUV ........................................................................................... 18
Figure 9. Boeing Echo Voyager UUV ........................................................................................... 18

Tables
Table 1. Congressional Action on FY2023 Large UV Funding Request ....................................... 36

Contacts
Author Information ........................................................................................................................ 38

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Introduction
This report provides background information and potential issues for Congress for three types of
large unmanned vehicles (UVs) that the Navy wants to develop and procure in FY2023 and
beyond:
 Large Unmanned Surface Vehicles (LUSVs);
 Medium Unmanned Surface Vehicles (MUSVs); and
 Extra-large Unmanned Undersea Vehicles (XLUUVs).
The Navy wants to acquire these large UVs 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 FY2023 budget requests $549.3
million in research and development funding for these large UVs and LUSV/MUSV-enabling
technologies, and $60.7 million in additional funding for core technologies for XLUUV and other
Navy UUVs.
The issue for Congress is whether to approve, reject, or modify the Navy’s acquisition strategies
and funding requests for these large UVs. The Navy’s proposals for developing and procuring
them pose a number of oversight issues for Congress. Congress’s decisions on these issues could
substantially affect Navy capabilities and funding requirements and the shipbuilding and UV
industrial bases.
In addition to the large UVs covered in this report, the Navy also wants to develop and procure
smaller USVs and UUVs, as well as unmanned aerial vehicles (UAVs) of various sizes. Other
U.S. military services are developing, procuring, and operating their own types of UVs. Separate
CRS reports address some of these efforts.1
Background
Navy USVs and UUVs in General
UVs in the Navy
UVs are one of several new capabilities—along with directed-energy weapons, hypersonic
weapons, artificial intelligence, cyber capabilities, and quantum technologies—that the Navy and
other U.S. military services are pursuing to meet emerging military challenges, particularly from
China.2 UVs can be equipped with sensors, weapons, or other payloads, and can be operated
remotely, semi-autonomously, or (with technological advancements) autonomously. They can be
individually less expensive to procure than manned ships and aircraft because their designs do not
need to incorporate spaces and support equipment for onboard human operators. UVs can be

1 See, for example, CRS Report R45519, The Army’s Optionally Manned Fighting Vehicle (OMFV) Program:
Background and Issues for Congress
, by Andrew Feickert, and CRS In Focus IF11150, Defense Primer: U.S. Policy on
Lethal Autonomous Weapon Systems
, by Kelley M. Sayler.
2 For a CRS report on advanced military technologies, see CRS In Focus IF11105, Defense Primer: Emerging
Technologies
, by Kelley M. Sayler.
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particularly suitable for long-duration missions that might tax the physical endurance of onboard
human operators, or missions that pose a high risk of injury, death, or capture of onboard human
operators—so-called “three D” missions, meaning missions that are dull, dirty, or dangerous.3
The Navy has been developing and experimenting with various types of UVs for many years, and
has transitioned some of these efforts (particularly those for UAVs) into procurement programs.
Even so, some observers have occasionally expressed dissatisfaction with what they view as the
Navy’s slow pace in transitioning UV development efforts into programs for procuring UVs in
quantity and integrating them into the operational fleet.
March 2021 Campaign Framework Document for UVs
On March 16, 2021, the Department of the Navy released a “campaign framework” (i.e., overall
strategy) document for developing and acquiring Navy and Marine UVs of various types and
integrating them into U.S. naval operations.4
Smaller and Larger Navy USVs and UUVs
In addition to the large UVs covered in this report, the Navy also wants to develop and procure
smaller USVs and UUVs that can be deployed from manned Navy ships and submarines to
extend the operational reach of those ships and submarines. The large UVs covered in this CRS
report, in contrast, are more likely to be deployed directly from pier to perform missions that
might otherwise be assigned to manned ships and submarines.
Large UVs and Navy Ship Count
Because the large UVs covered in this report can be deployed directly from pier to perform
missions that might otherwise be assigned to manned ships and submarines, the top-level count of
the desired future number of ships in the Navy now increasingly includes two figures—one for
manned ships, and another for larger USVs and UUVs.
Large UVs as Part of More Distributed Navy Fleet Architecture
The Navy wants to acquire these large UVs 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 and the Department of Defense (DOD) have
been working since 2019 to develop a new Navy force-level goal reflecting this new fleet mix.
The Navy’s FY2023 30-year (FY2023-FY2052) shipbuilding plan, released on April 20, 2022,

3 See, for example, Ann Diab, “Drones Perform the Dull, Dirty, or Dangerous Work,” Tech.co, November 12, 2014;
Bonnie Robinson, “Dull, Dirty, Dangerous Mission? Send in the Robot Vehicle,” U.S. Army, August 20, 2015;
Bernard Marr, “The 4 Ds Of Robotization: Dull, Dirty, Dangerous And Dear,” Forbes, October 16, 2017.
4 Department of the Navy, Department of the Navy Unmanned Campaign Framework, March 16, 2021, 37 pp. See also
Megan Eckstein, “Navy, Marines Unveil How They Will Buy and Operate Future Pilotless Aircraft and Crewless
Ships,” USNI News, March 16, 2021; Gina Harkins, “Why You Should Trust Drone Ships and Unmanned Tech,
According to the Navy,” Military.com, March 16, 2021; Stew Magnuson, “Just In: Navy, Marine Corps Unmanned
Framework Calls For ‘Capabilities’ Over Platforms,” National Defense, March 16, 2021; Seapower Staff, “Navy,
Marine Corps Release Unmanned Campaign Plan,” Seapower, March 16, 2021; Jordan Wolman, “Looking to the
Future of Combat and Competition, Navy Releases Much-Anticipated Campaign Plan on Unmanned Systems,” Inside
Defense
, March 16, 2021.
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includes a table summarizing the results of studies that have been conducted on the new force-
level goal. These studies outline potential future fleets with 27 to 153 large USVs and 18 to 51
large UUVs.5
Acquisition Strategies and Enabling Technologies
Acquisition Strategies Restructured Following Congressional Markups
In marking up the Navy’s proposed FY2020-FY2022 budgets, the congressional defense
committees expressed concerns over whether the Navy’s acquisition strategies provided enough
time to adequately develop concepts of operations and key technologies for these large UVs,
particularly the LUSV, and included legislative provisions intended to address these concerns.6 In
response to these markups, the Navy restructured its acquisition strategy for the LUSV program
so as to comply with these legislative provisions and provide more time for developing
operational concepts and key technologies before entering into serial production of deployable
units. Land-based testing of propulsion equipment intended for the LUSV and MUSV forms a
key element of the restructured acquisition strategy.
Prototypes
The LUSV and MUSV programs are building on USV prototypes and other development work
done by the DOD’s Strategic Capabilities Office (SCO). SCO’s effort to develop USVs is called
Ghost Fleet, and its LUSV development effort within Ghost Fleet was called Overlord. A January
12, 2022, press report stated
Project Overlord, an experimental unmanned surface vehicle program, has completed its
work and has been shut down by the Strategic Capabilities Office, a secretive research and
development organization within the Pentagon, a Navy official revealed today.
Its conclusion is a significant milestone, marking a period of transition between the
Pentagon’s research and development enterprise and a complete entry into the Navy’s fleet.
Overlord, which produced four vessels in total that will be transferred to the Navy’s
developmental squadrons, ended in December with a capstone demonstration, Capt. Pete
Small, program manager for unmanned maritime systems, told attendees at the Surface
Navy Association’s national symposium.
“What did we gain out of that?” Small said referring to Project Overlord. “The first thing
we gained is the platforms. We’re getting those free of charge… It’s something on the order
of $370 million” over three years invested by the SCO into unmanned vessels.
That includes not just the platforms, but the technology and capabilities held within the
ships, such as the control software. With the SCO’s activities complete, the Overlord
vessels will be transferred to the Surface Warfare Development Squadron this month.7

5 For additional discussion, see CRS Report RL32665, Navy Force Structure and Shipbuilding Plans: Background and
Issues for Congress
, by Ronald O'Rourke.
6 In the William M. (Mac) Thornberry National Defense Authorization Act for Fiscal Year 2021 (H.R. 6395 /P.L. 116-
283 of January 1, 2021), these provisions included Sections 122 and 227.
7 Justin Katz, “SCO Ends Project Overlord, Shifts Unmanned Vssels to Navy,” Breaking Defense, January 12, 2022.
See also PEO Unmanned and Small Combatants (PEO USC) Public Affairs, “Strategic Capabilities Office Transfers
Overlord Unmanned Surface Vessels to U.S. Navy,” Naval Sea Systems Command, March 3, 2022.
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Figure 1 shows USV prototypes that have supported or are scheduled to support the LUSV and
MUSV programs. Figure 2 shows one of those prototypes, the Sea Hunter medium displacement
USV.
Figure 1. Prototypes Supporting the LUSV and MUSV Programs

Source: Slide 4 of Navy briefing entitled “PMS 406 Maritime Unmanned Systems, CAPT Pete Small,” briefing to
Surface Navy Association (SNA) annual symposium, January 12, 2022.
Surface Development Squadron
In May 2019, the Navy established a surface development squadron to help develop operational
concepts for LUSVs and MUSVs. The squadron was initially to consist of a Zumwalt (DDG-
1000) class destroyer and one Sea Hunter prototype. A second Sea Hunter prototype was
reportedly to be added around the end of FY2020, and LUSVs and MUSVs would then be added
as they become available.8

8 See, for example, Megan Eckstein, “Navy Stands Up Surface Development Squadron for DDG-1000, Unmanned
Experimentation,” USNI News, May 22, 2019; David B. Larter, “With Billions Planned in Funding, the US Navy
Charts Its Unmanned Future,” Defense News, May 6, 2019. See also Michael Fabey, “USN Seeks Path for Unmanned
Systems Operational Concepts,” Jane’s Navy International, May 16, 2019.
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Figure 2. Sea Hunter Prototype Medium Displacement USV

Source: Photograph credited to U.S. Navy accompanying John Grady, “Panel: Unmanned Surface Vessels Wil be
Significant Part of Future U.S. Fleet,” USNI News, April 15, 2019.
LUSV, MUSV, and LXUUV Programs in Brief
LUSV Program
Overview
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.9 Although referred to as UVs, 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.
Under the Navy’s FY2023 five-year (FY2023-FY2027) shipbuilding plan, procurement of
LUSVs through the Navy’s shipbuilding account is programmed to begin in FY2025. The plan
calls for the procurement of one LUSV in FY2025 at a cost of $315.0 million, two LUSVs in
FY2026 at a combined cost of $522.5 million (an average of 261.3 million each), and three
LUSVs in FY2027 at a combined cost of $722.7 million (an average of $240.9 million each).

9 Source: Navy FY2022 program briefing on LUSV and MUSV programs for CRS and CBO, July 14, 2021.
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LUSV Prototypes
Figure 3, Figure 4, and Figure 5 show photographs of LUSV prototypes.
Figure 3. USV Prototypes

Source: Photograph from briefing slide entitled “UMS [unmanned maritime systems] at Sea,” slide 4 of 5
(including cover slide) of Navy briefing entitled “PMS 406 Unmanned Maritime Systems, Program Overview,
August 2021, prepared for Sea-Air-Space Exposition. The briefing slide states that the photograph shows
“Overlord USVs Ranger & Nomad on the West Coast.”
Figure 4. LUSV Prototype

Source: Cropped version of photograph accompanying Mallory Shelbourne, “6 Companies Awarded Contracts
to Start Work on Large Unmanned Surface Vehicle,” USNI News, September 4, 2020. The caption to the
photograph states in part: “A Ghost Fleet Overlord test vessel takes part in a capstone demonstration during the
conclusion of Phase I of the program in September.” The photo is credited to the U.S. Navy.
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Figure 5. LUSV Prototype

Source: Cropped version of photograph accompanying Mallory Shelbourne, “6 Companies Awarded Contracts
to Start Work on Large Unmanned Surface Vehicle,” USNI News, September 4, 2020. The caption to the
photograph states in part: “A Ghost Fleet Overlord test vessel takes part in a capstone demonstration during the
conclusion of Phase I of the program in September.” The photo is credited to the U.S. Navy.
Navy Description
The Navy states that
LUSVs will provide affordable, high endurance ships able to accommodate various
payloads for unmanned missions and augment the Navy’s manned surface force. LUSVs
will be capable of semiautonomous operation, with operators in-the-loop or on-the-loop.
USV Command and Control (C2) will be maintained via an afloat element (i.e., embarked
on a United States Navy (USN) combatant/other assigned afloat asset) or via an ashore
element (C2 station ashore)....
LUSV is a key enabler of the Navy’s Distributed Maritime Operations (DMO) concept,
which includes being able to forward deploy and team with individual manned combatants
or augment battle groups. LUSV will complement the Navy’s manned combatant force by
delivering increased readiness, capability and needed capacity at lower procurement and
sustainment costs and reduced risk to sailors. While unmanned surface vehicles are new
additions to the fleet units, LUSV will combine robust and proven commercial vessel
specifications with existing military payloads to rapidly and affordably expand the capacity
and capability of the surface fleet....
The Large Unmanned Surface Vessel (LUSV) development is supported by research and
development prototype vessels (Overlord prototype vessels already purchased) intended to
demonstrate successful integration of government furnished Command, Control,
Communications, Computers and Intelligence (C4I), combat systems, and the reliability of
automated hull, mechanical, and electrical (HM&E) systems. The program leverages years
of investment and full scale demonstration efforts in autonomy, endurance, command and
control, payloads and testing from the Defense Advanced research Projects Agency
(DARPA) Anti-Submarine Warfare Continuous Trail Unmanned Vessel (ACTUV), Office
of Naval Research (ONR) Medium Displacement Unmanned Surface Vehicle
(MDUSV)/Sea Hunter (FY 2017 to FY 2021), and Office of the Secretary of Defense
Strategic Capabilities Office (OSD- SCO) Ghost Fleet Overlord Large USV
experimentation effort (FY 2018 - FY 2021). The combination of fleet-ready C2 solutions
developed by the Ghost Fleet Overlord program and man-in-the-loop or man-on-the-loop
control will reduce the risk of fleet integration of unmanned surface vehicles and allow
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autonomy and payload technologies to develop in parallel with fielding vehicles with
standardized interfaces.10
The Navy states further that
The major change between FY 2022 and FY 2023 is the delay in planned Detail Design
and Construction (DD&C) for the initial production LUSV to FY 2025. The Navy
instituted a comprehensive system engineering framework and supporting land and sea
based prototyping plan, which will be completed prior to commencing the formal program
of record and LUSV production....
The supporting land and sea based prototyping plan will use the four Overlord Prototype
vessels (vessels procured in FY20 will be delivered in FY22) and various land based testing
facilities to mature enabling technologies and qualify representative machinery. In support
of the updated developmental and prototyping plan, the Navy is aligning Detail Design and
Construction for the initial production LUSVs with the risk reduction and qualification
plans described in the program System Engineering Framework (Work Breakdown
Structure (WBS)). In addition, the outcome of the Offensive Surface Fires Analysis of
Alternatives (OSF AoA) is supporting the refinement of program requirements leading to
the validation of a Capability Development Document, acquisition strategy, and timing for
procurement. The Navy’s new plan does not include procurement of any additional
prototype vessels.
The LUSV will be capable of weeks-long deployments and trans-oceanic transits and
operate aggregated with Carrier Strike Groups (CSGs), Amphibious Ready Groups
(ARGs), Surface Action Groups (SAGs), and individual manned combatants. The LUSV
will be capable of autonomous navigation, transit planning, and COLREGS-compliant11
maneuvering and will be designed with automated propulsion, electrical generation, and
support systems. LUSV missions will be conducted with operators in-the-loop (with
continuous or near-continuous observation or control) or on-the-loop (autonomous
operation that prompts operator action/intervention from sensory input or autonomous
behaviors). LUSVs with integrated payload capability and prototypes employing non-
organic payloads will not be capable of autonomous payload engagement or execution of
a complete detect-to-engage sequence. The vessel will be incapable of payload activation,
deactivation, or engagement without the deliberate action of a remote, off-hull human
operator in the command and control loop. The program will integrate current Navy combat
systems programs of record that have been adapted to enable remote monitoring and
operational control from an off-hull command and control point, and will not be equipped
with components that would enable payload engagement from onboard the vessel. USV
Command and Control (C2) will be maintained via an afloat element (i.e., embarked on a
United States Navy (USN) combatant), or via the ashore element (C2 station ashore).
The LUSV program is continuing to execute a comprehensive land and sea-based
prototyping strategy to develop and deliver incremental capability increases, demonstrate
key autonomy and automation enablers, and improve reliability of representative
machinery....
The LUSV Performance Specification that will be released under the Detail Design and
Construction (DD&C) solicitation will heavily leverage the results of the prototype USV
developmental effort, land based testing plan, LUSV industry design studies, and continued
engagement with industry....

10 Department of Defense, Fiscal Year (FY) 2023 Budget Estimates, Navy Justification Book Volume 2 of 5, Research,
Development, Test & Evaluation, Navy
, April 2022, pp. 11-12 (PDF pages 107-108 of 1608).
11 This is a reference to the October 1972 multilateral convention on international regulations for preventing collisions
at sea, commonly known as the collision regulations (COLREGs) or the “rules of the road” (28 UST 3459; TIAS
8587), to which the United States and more than 150 countries are parties.
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The Navy is also executing a comprehensive reliability plan with the intent to discover and
implement reliability enhancements into USV machinery plants... as well as provide a
means to qualify LUSV-representative machinery plants prior to award of the initial
production LUSVs.... Additionally, the Navy is executing a parallel effort to qualify the
main engines for the prototype MUSV (same as on 3 of 4 Overlord prototype USVs), which
concludes in FY 2023. In FY 2021, the Navy worked with the American Bureau of
Shipping (ABS) to develop USV machinery plant standards, which will provide potential
vendors a path to prove reliability of proposed architectures and equipment for production
LUSVs.
As part of the long term reliability plan in FY 2022, the Navy extended the LUSV Studies
Contracts to include government oversight of a robust and comprehensive industry-led
main machinery and electrical distribution qualification plan to provide. The plan provides
the opportunity to qualify representative machinery from multiple manufacturers through
the execution of testing at vendor sites, ultimately providing increased flexibility and
options for vendors in the competitive LUSV DD&C contract. In parallel, the Navy is
continuing to test ancillary equipment and develop solutions for government-furnished
engineering operations autonomy modules and machinery control systems at the Land
Based Test Site at Naval Surface Warfare Center, Philadelphia.12
An August 3, 2021, press report states
For the foreseeable future, the LUSVs will require a small crew detachment aboard to carry
out tasks not conducive to machines.
“We do envision accommodations for a small detachment of personnel. Those people are
not intended to be driving or operating the boat directly, but we provide those
accommodations as a risk manager for operations, that can’t be automated or haven’t been
automated yet, like refueling,” Capt. Pete Small, Navy Program Manager for USVs, said
Monday at the Sea Air Space 2021 symposium.
“They could still be aboard also for force protection or other measures that are required as
we continue to refine concepts of operations.”...
“The current way we operate them is that we pilot the USVs into and out of port in manual
mode with a small crew on board. This is consistent with the Navy’s plans for medium
USV and large USV,” Small said last week at a virtual conference hosted by the
Association for Unmanned Vehicle Systems International (AUVSI).
“Once the USVs is in the open ocean, we make the transition to autonomous mode and
continue with operations that include remote mission planning, command and control and
supervision.”
In terms of how manning evolves for LUSV, “we’re going to flesh that out over the next
several years,” Small said.13
Analysis of Alternatives (AOA)
The Navy is conducting an analysis of alternatives (AOA) to compare the cost-effectiveness of
the LUSV to a range of alternative surface platforms, including modified naval vessel designs
such as amphibious ships, expeditionary fast transport (EPF) ships, and expeditionary sea base
(ESB) ships, modified commercial vessel designs such as container ships and bulk carriers, new

12 Department of Defense, Fiscal Year (FY) 2023 Budget Estimates, Navy Justification Book Volume 2 of 5, Research,
Development, Test & Evaluation, Navy
, April 2022, pp. 13-14 (PDF pages 109-110 of 1608).
13 Sam LaGrone, “Navy: Large USV Will Require Small Crews for the Next Several Years,” USNI News, August 3,
2021.
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naval vessel designs, and new commercial vessel designs.14 A January 21, 2022, press report
stated that “originally, the Navy was aiming to accomplish the [AOA] by October 2021. Late last
year, the target slipped to early this year.” The press report quoted a Navy official as saying that
the AOA is now expected to be completed by the end of April 2022.15 A March 22, 2022, press
report similarly stated that the Navy expected the study to be completed by the end of April
2022.16
September 4, 2020, Contract Awards
On September 4, 2020, DOD announced the following six contract awards for industry studies on
the LUSV:
Huntington Ingalls Inc., Pascagoula, Mississippi (N00024-20-C-6319); Lockheed Martin
Corp., Baltimore, Maryland (N00024-20-C-6320); Bollinger Shipyards Lockport LLC,
Lockport, Louisiana (N00024-20-C-6316); Marinette Marine Corp., Marinette, Wisconsin
(N00024-20-C-6317); Gibbs & Cox Inc., Arlington, Virginia (N0002420C6318); and
Austal USA LLC, Mobile, Alabama (N00024-20-C-6315), are each being awarded a firm-
fixed price contract for studies of a Large Unmanned Surface Vessel with a combined value
across all awards of $41,985,112.
Each contract includes an option for engineering support, that if exercised, would bring the
cumulative value for all awards to $59,476,146.
—The contract awarded to Huntington Ingalls Inc. [HII] is $7,000,000;
—the contract awarded to Lockheed Martin Corp. is $6,999,978;
—the contract awarded to Bollinger Shipyards Lockport LLC, is $6,996,832;
—the contract awarded to Marinette Marine Corp. is $6,999,783;
—the contract awarded to Gibbs & Cox Inc. is $6,989,499; and
—the contract awarded to Austal USA LLC is $6,999,020.

14 The Navy stated in 2021 that
As directed in the FY 2021 National Defense Authorization Act [Section 227(e) of H.R. 6395/P.L.
116-283 of January 1, 2021], the Navy is conducting a Distributed Offensive Surface Fires AoA
[analysis of alternatives] to compare the currently planned large unmanned surface vessel (LUSV)
with an integrated missile launcher payload against a broad range of alternative surface platforms
and capabilities to determine the most appropriate vessel to deliver additional missile capability and
capacity to the surface force.
(Statement of Frederick J. Stefany, Acting Assistant Secretary of the Navy for Research,
Development and Acquisition (ASN (RD&A)) and Vice Admiral James W. Kilby, Deputy Chief of
Naval Operations, Warfighting Requirements and Capabilities (OPNAV N9) and Lieutenant
General Eric M. Smith, Deputy Commandant, Combat Development and Integration, Commanding
General, Marine Corps Combat Development Command, before the Subcommittee on Seapower of
the Senate Armed Services Committee on Department of the Navy Fiscal Year 2022 Budget
Request for Seapower, June 8, 2021, p. 14.)
See also Jason Sherman, “Navy Considering Alternatives to LUSV, Packing Amphibs, Commercial Designs More with
Long-Range Missiles,” Inside Defense, April 9, 2021.
15 Jason Sherman, “Navy Now Eyeing April for LUSV Analysis of Alternatives Completion,” Inside Defense, January
21, 2022.
16 Megan Eckstein, “US Navy Considers Alternatives to Unmanned Boats with Missiles,” Defense News, March 22,
2022.
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Work will be performed in various locations in the contiguous U.S. in accordance with
each contract and is expected to be complete by August 2021, and if option(s) are exercised,
work is expected to be complete by May 2022.
Fiscal 2020 research, development, test and evaluation (Navy) funds in the amount
$41,985,112 will be obligated at time of award and will not expire at the end of the current
fiscal year.
These contracts were competitively procured via Federal Business Opportunities (now
beta.SAM.gov) with eight offers received. The Naval Sea Systems Command,
Washington, D.C., is the contracting activity.17
A September 4, 2020, press report about the contract awards stated
“These contracts were established in order to refine specifications and requirements for a
Large Unmanned Surface Vessel and conduct reliability studies informed by industry
partners with potential solutions prior to release of a Detail Design and Construction
contract,” Navy spokesman Capt. Danny Hernandez told USNI News in a statement.
“The studies effort is designed to provide robust collaboration with government and
industry to assist in maturation of platform specifications, and ensure achievable technical
requirements are in place for a separate LUSV DD&C competition.”…
“The LUSV studies will support efforts that facilitate requirements refinement,
development of an affordable and effective platform; provide opportunities to continue
maturing the performance specifications and conduct analysis of alternative design
approaches; facilitate reliability improvements and plans for government-furnished
equipment and mechanical and electrical systems; and support development of cost
reduction and other affordability initiatives,” Hernandez said.18
July 29, 2022, Contract Modifications
On July 29, 2022, the Navy awarded modifications to the six contracts discussed above, as
follows:
Huntington Ingalls Inc., Pascagoula, Mississippi, is awarded a $13,071,106 firm-fixed-
price modification to previously awarded contract N00024-20-C-6319 for continued
studies of a large unmanned surface vessel. This contract modification includes options
which, if exercised, would bring the cumulative value of this contract modification to $
15,071,106. Work will be performed in Pascagoula, Mississippi, and is expected to be
completed by September 2024. If all options are exercised, work will continue through
September 2024....
Lockheed Martin Corp., Baltimore, Maryland, is awarded an $11,320,904 firm-fixed-price
modification to previously awarded contract N00024-20-C-6320 for continued studies of
a large unmanned surface vessel. This contract modification includes options which, if
exercised, would bring the cumulative value of this contract modification to $15,070,904.
Work will be performed in Moorestown New Jersey, and is expected to be completed by
September 2024. If all options are exercised, work will continue through September
2024....

17 Department of Defense, “Contracts For Sept. 4, 2020,” accessed September 8, 2020. The announcement is posted as
a single, unbroken paragraph. In reprinting the text of the announcement, CRS broke the announcement into the smaller
paragraphs shown here to make the announcement easier to read.
18 Mallory Shelbourne, “6 Companies Awarded Contracts to Start Work on Large Unmanned Surface Vehicle,” USNI
News
, September 4, 2020. See also Paul McLeary, “Navy Awards Study Contracts On Large Unmanned Ship—As
Congress Watches Closely,” Breaking Defense, September 4, 2020.
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Marinette Marine Corp., Marinette, Wisconsin, is awarded a $10,212,620 firm-fixed-price
modification to previously awarded contract N00024-20-C-6317 for continued studies of
a large unmanned surface vessel. Work will be performed in Marinette, Wisconsin, and is
expected to be completed by September 2024....
Bollinger Shipyards Lockport LLC, Lockport, Louisiana, is awarded a $9,428,770 firm-
fixed-price modification to previously awarded contract N00024-20-C-6316 for continued
studies of a large unmanned surface vessel. This contract modification includes options
which, if exercised, would bring the cumulative value of this contract modification to
$13,958,770. Work will be performed in Lockport, Louisiana, and is expected to be
completed by September 2024. If all options are exercised, work will continue through
September 2024....
Austal USA LLC, Mobile, Alabama, is awarded a $9,115,310 firm-fixed-price
modification to previously awarded contract N00024-20-C-6315 for continued studies of
a large unmanned surface vessel. This contract modification includes options which, if
exercised, would bring the cumulative value of this contract modification to $13,285,309.
Work will be performed in Mobile, Alabama, and is expected to be completed by
September 2024. If all options are exercised, work will continue through September,
2024....
Gibbs & Cox Inc., Arlington, Virginia, is awarded an $8,981,231 firm-fixed-price
modification to previously awarded contract N00024-20-C-6318 for continued studies of
a large unmanned surface vessel. This contract modification includes options which, if
exercised, would bring the cumulative value of this contract modification to $15,071,231.
Work will be performed in Arlington, Virginia, and is expected to be completed by
September 2024.19
MUSV Program
Overview
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 is pursuing the MUSV program as a rapid
prototyping effort under what is known as Section 804 middle tier acquisition authority.20 The
Navy’s FY2023 five-year (FY2023-FY2027) shipbuilding plan does not include the procurement
of any MUSVs during the period FY2023-FY2027.
April 2022 Reported Remarks of Chief of Naval Operations
An April 28, 2022, press report states

19 Department of Defense, “Contracts For July 29, 2022,” accessed August 29, 2022. See also Rich Abott, “Navy
Continues Six LUSV Study Contracts,” Defense Daily, August 5, 2022.
20 This is a reference to Section 804 of the FY2016 National Defense Authorization Act (S. 1356/P.L. 114-92 of
November 25, 2015), which provided rapid prototyping authority. For more on this authority, see “Middle Tier
Acquisition (Section 804),” MITRE, undated, accessed May 11, 2022, at https://aida.mitre.org/middle-tier/; and
“Acquisition Process, Middle Tier Acquisition (Section 804),” AcqNotes, updated February 13, 2022, accessed May
11, 2022, at http://acqnotes.com/acqnote/acquisitions/middle-tier-acquisitions.
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The Navy is rethinking its planned portfolio of unmanned surface vehicles following
testing of a variety of USVs in the Middle East, the service’s top officer said on
Thursday[April 28]....
On Thursday, Chief of Naval Operations Adm. Mike Gilday said the service might be
rethinking buying the MUSV after a series of exercises and experiments in U.S. 5th Fleet
with Combined Task Force 59, which stood up in September.
“I don’t know if we’ll have a medium unmanned or not. The stuff that [Vice Adm. Brad]
Cooper’s doing right now with CTF [combined task force] 59—using small unmanned
[vehicles] on the scene in the air to sense the environment … in order to yield a common
operational picture for allies and partners, as well as 5th Fleet headquarters, has changed
my thinking on the direction of unmanned,” Gilday said during a Thursday U.S. Naval
Institute-CSIS Maritime Security Dialogue.
“We are learning so fast and fielding these capabilities out to the fleet, or potentially
fielding them quickly inside the [Future Years Defense Plan], we may be able to close
capability gaps with small expendable unmanned [vehicles] off of any platform,” Gilday
said, “rather than thinking that we have to build, you know, a large [USV]. There may be
room for that. I’m not saying that we don’t need an MUSV. I’m saying it’ll cause us to
consider numbers [of such platforms that may be needed].”...
... the Navy might be able to get the sensor capability it wanted from MUSV through fused
data from networked commercial systems to get an accurate maritime awareness picture
more affordably. The 5th fleet started experimenting late last year with a 23-foot Saildrone
Explorer out of Jordan and MARTAC’s Mantas T12 USV out of Bahrain. Those ongoing
deployments are continuing to refine the Navy’s concepts for unmanned systems.21
Another April 28, 2022, press report similarly stated
Chief of Naval Operations Adm. Michael Gilday today cast doubt on whether the Medium
Unmanned Surface Vessel will have a place in the service’s fleet in the near future, citing
work done by US 5th Fleet as having “changed my thinking on the direction of unmanned”
ships.
During a virtual event at the US Naval Institute and co-hosted by Center for Strategic and
International Studies, Gilday was discussing what platforms and capabilities the service is
developing for the 2030s and beyond.
“Flight III DDGs [destroyers] will pave the way” for surface fleet capabilities, he said.
“2030 is when we’re looking at DDG(X)… By that time, I think we’ll be in a better place
with [the Large Unmanned Surface Vessel]. I don’t know if we’ll have a medium
unmanned [surface vessel] or not.”
The Navy’s top admiral said the work done by Vice Adm. Brad Cooper, US 5th Fleet chief,
has led him to believe the service may be able to “close capability gaps with small
expendable unmanned” vessels off of any platform. Cooper leads Task Force 59, a special
panel inside the Navy, designed specifically to experiment with and test unmanned
platforms.
Gilday followed those remarks with a hedge, however, suggesting the program’s fate is not
predetermined.

21 Sam LaGrone, “Navy Rethinking Medium Unmanned Surface Vehicle After Middle East Tests, Says CNO Gilday,”
USNI News, April 28, 2022.
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“There may be room for [larger unmanned platforms],” he added. “I’m not saying we don’t
need an MUSV. I’m saying that it’ll cause us to consider numbers [of such platforms that
may be needed] and what potential payloads they’re going to have.”22
Navy Description
The Navy states that
The MUSV is defined as having a reconfigurable mission capability which is accomplished
via modular payloads with an initial capability to support Battlespace Awareness through
supporting Intelligence, Surveillance and Reconnaissance (ISR) and Information
Operations (IO) mission areas....
MUSVs will support the Navy’s ability to produce, deploy and disburse ISR/IO capabilities
in sufficient quantities and provide/improve distributed situational awareness in maritime
Areas of Responsibility (AORs). MUSVs will be capable of weeks-long deployments and
trans-oceanic transits, and operate aggregated with Carrier Strike Groups (CSGs) and
Surface Action Groups (SAGs), as well as have the ability to deploy independently. The
MUSV will be a key enabler of the Navy’s Distributed Maritime Operations (DMO)
concept.
In FY 2020, the Navy conducted a full and open competition for a MUSV prototype,
conducting source selection activities Q1-Q3 of FY20. In July 2020, the Navy announced
they had awarded a Detail Design & Fabrication (DD&F) contract to L3 Harris for the
delivery of the first MUSV prototype for $35M. The contract contains options for up to 8
additional MUSVs (9 total) for a total contract price of $281M. L3 Harris will be the system
integrator, while also supplying the autonomy and perception systems. Subcontractors
Gibbs & Cox and Incat Crowther will provide vessel design and modification services,
while the vessel will be produced by Swiftships Shipyard. All work will be performed in
various sites along the Louisiana Gulf Coast.23
Contract Award
As noted in the above-quoted passage, on July 13, 2020, the Navy announced that it had awarded
“a $34,999,948 contract to L3[Harris] Technologies, Inc. for the development of a single Medium
Unmanned Surface Vehicle (MUSV) prototype, with options to procure up to eight additional
MUSVs. The award follows a full and open competitive procurement process. Funding is in place
on this contract for the initial prototype. With all options exercised, the contract is valued at
$281,435,446 if additional funding is provided in future budget years.”24 The Navy reportedly
stated that there were five competitors for the contract, but did not identify the other four.25
Figure 6 shows a rendering of L3Harris’s design concept. L3Harris states that
will integrate the company’s ASView™ autonomy technology into a purpose-built 195-
foot commercially derived vehicle from a facility along the Gulf Coast of Louisiana. The

22 Justin Katz, “Gilday: ‘I Don’t Know’ If Navy’s Future Fleet Will Include Medium USVs,” Breaking Defense, April
28, 2022. See also Rich Abott, “CNO Unsure If Navy Will Need MUSVs, Explains Retiring Ground-Based Growlers,”
Defense Daily, April 28, 2022.
23 Department of Defense, Fiscal Year (FY) 2023 Budget Estimates, Navy Justification Book Volume 2 of 5, Research,
Development, Test & Evaluation, Navy
, April 2022, p. 1399 (PDF page 1495 of 1608).
24 PEO Unmanned and Small Combatants Public Affairs, “Navy Awards Contract for Medium Unmanned Surface
Vehicle Prototype,” Naval Sea Systems Command, July 13, 2020.
25 Rich Abott, “L3Harris Wins $35 Million MUSV Prototype Contract,” Defense Daily, July 13, 2020. See also Sam
LaGrone, “Navy Awards Contract for First Vessel In Its Family of Unmanned Surface Vehicles,” USNI News, July 14
(updated July 15), 2020; Paul McLeary, “Navy Inks Deal For New Unmanned Fleet,” Breaking Defense, July 13, 2020.
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MUSV will provide intelligence, surveillance and reconnaissance to the fleet while
maneuvering autonomously and complying with international Collision Regulations, even
in operational environments.…
L3Harris will be the systems integrator and provide the mission autonomy and perception
technology as the prime contractor on the program. The program team includes Gibbs &
Cox and Incat Crowther who will provide the ship design and Swiftships will complete the
construction of the vehicle.26
Figure 6. Rendering of L3Harris Design Concept for MUSV

Source: L3Harris Technologies, “L3Harris Technologies Awarded Medium Unmanned Surface Vehicle Program
from US Navy,” August 18, 2020. See also Richard R. Burgess, “Navy’s Medium USV to Be Based on Commercial
Vehicle,” Seapower, August 19, 2020.
XLUUV Program
Overview
The XLUUV program, also known as the Orca program, was established to address a Joint
Emergent Operational Need (JEON). The Navy defines XLUUVs as UUVs with a diameter of
more than 84 inches, meaning that XLUUVs are to be too large to be launched from a manned
Navy submarine.27 Consequently, XLUUVs instead will transported to a forward operating port
and then launched from a pier. The Department of the Navy’s March 16, 2021, unmanned
campaign framework document states that the XLUUV will be designed “to accommodate a
variety of large payloads….”28 The Navy testified on March 18, 2021, that mines will be the
initial payload for XLUUVs.29 More specifically, the Navy wants to use XLUUVs to, among
other things, covertly deploy the Hammerhead mine, a planned mine that would be tethered to the

26 L3Harris Technologies, “L3Harris Technologies Awarded Medium Unmanned Surface Vehicle Program from US
Navy,” August 18, 2020. See also Audrey Decker, “First MUSV Platform Will Feature Broad Payload Area,” Inside
Defense,
January 20, 2022.
27 Navy submarines equipped with large-diameter vertical launch tubes can launch missiles or other payloads with
diameters of up to about 83 inches.
28 Department of the Navy, Department of the Navy Unmanned Campaign Framework, March 16, 2021, p. 16.
29 Richard R. Burgess, “Navy’s Orca XLUUV to Have Mine-Laying Mission, Adm. Kilby Says,” Seapower, March 18,
2021.
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seabed and armed with an antisubmarine torpedo, broadly similar to the Navy’s Cold War-era
CAPTOR (encapsulated torpedo) mine.30
The first five XLUUVs were funded in FY2019 through the Navy’s research and development
appropriation account. The Navy conducted a competition for the design of the XLUUV, and
announced on February 13, 2019, that it had selected Boeing to fabricate, test, and deliver the first
four Orca XLUUVs and associated support elements.31 (The other bidder was a team led by
Lockheed Martin.) On March 27, 2019, the Navy announced that the award to Boeing had been
expanded to include the fifth Orca.32 Boeing has partnered with the Technical Solutions division
of Huntington Ingalls Industries (HII) to build Orca XLUUVs.33 (Another division of HII—
Newport News Shipbuilding (NNS) of Newport News, VA—is one of the Navy’s two submarine
builders.)
Under the Navy’s FY2023 five-year (FY2023-FY2027) shipbuilding plan, procurement of
additional XLUUVs through the Other Procurement, Navy (OPN) account is scheduled to begin
in FY2024. The plan calls for the procurement of one XLUUV in FY2024 at a cost of $113.6
million, one XLUUV in FY2025 at a cost of $107.6 million, two XLUUVs in FY2026 at a
combined cost of $226.6 million (an average cost of $113.3 million each), and two XLUUVs in
FY2027 at a combined cost of $231.1 million (an average cost of $115.6 million each).
Navy Description
The Navy states that
The Orca XLUUV effort is established to address a Joint Emergent Operational Need
(JEON). Orca XLUUV is a multi-phased accelerated acquisition effort to rapidly deliver
capability to the Fleet. Phase 1 was a competitively sourced design effort. Phase 2 down
selected to one of the Phase 1 vendors in FY 2019 for fabrication and testing of the vehicle
and support elements. Testing and delivery of the vehicles and support elements has been
delayed to FY22-23 due to contractor challenges and supplier issues. The Navy is working
with Boeing to mitigate schedule delays and execute risk reduction testing through the
addition of a designated test and training asset. The Navy is updating facilities at the Naval
Base Ventura County site for testing, training, and work-ups, in coordination with large
unmanned surface vessel testing for cost efficiencies. Fabrication awards of additional
Orca XLUUV systems are planned for FY24 and out, gradually ramping up quantities in
future fiscal years, depending on the progress from the first five systems. XLUUV will
have a modular payload bay, with defined interfaces that current and future payloads must
adhere to for employment from the vehicle. The Orca XLUUV effort will integrate the
currently required payload, and potential future payloads will be developed, evaluated, and
preliminarily integrated leveraging the Core Technologies Program Element 0604029N.

30 For a discussion of the Hammerhead mine, see, for example, David Hambling, “With Hammerhead Mine, U.S. Navy
Plots New Style Of Warfare To Tip Balance In South China Sea,” Forbes, October 22, 2020. See also Kyle Mizokami,
“The Navy’s ‘Ghost Fleet’ of Robo-Subs Will Drop Deadly Surprises for Enemies,” Popular Mechanics, June 2, 2022;
Rich Abott, “Navy Orca XLUUV To Carry 34-Foot Payload Module, Buying 6th Test Vessel,” Defense Daily, May 31,
2022; Dan Parsons, “Navy’s 85-Foot Orca Unmanned Submarine Will Be A Minelayer First,” The Drive, May 27,
21022; Audrey Decker, “Navy’s XLUUV Will Fill ‘Specific Mission’ in INDOPACOM,” Inside Defense, November
22, 2021.
31 Department of Defense, Contracts for Feb. 13, 2019.
32 Department of Defense, Contracts for March 27, 2019.
33 See, for example, Hugh Lessig, “Shipbuilder Lends a Hand with Rise of Robot Submarines,” Defense News, May 26,
2019.
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Additional XLUUV technologies/capabilities risk reduction will occur in parallel,
leveraging the competitive Industrial base.34
Boeing Echo Voyager
Boeing’s Orca XLUUV design will be informed by (but will differ in certain respects from) the
design of Boeing’s Echo Voyager UUV (Figure 7, Figure 8, and Figure 9).35 Echo Voyager is
roughly the size of a subway car—it is 51 feet long and has a rectangular cross section of 8.5 feet
by 8.5 feet, a weight in the air of 50 tons, and a range of up to 6,500 nautical miles. It can
accommodate a modular payload section up to 34 feet in length, increasing its length to as much
as 85 feet. A 34-foot modular payload section provides about 2,000 cubic feet of internal payload
volume; a shorter (14-foot) section provides about 900 cubic feet. Echo Voyager can also
accommodate external payloads.36
Figure 7. Boeing Echo Voyager UUV

Source: Boeing photograph posted at https://www.boeing.com/defense/autonomous-systems/echo-voyager/
index.page#/gallery.

34 Department of Defense, Fiscal Year (FY) 2023 Budget Estimates, Navy Justification Book Volume 2 of 5, Research,
Development, Test & Evaluation, Navy
, April 2022, p. 1297 (PDF page 1393 of 1608).
35 See, for example, Hugh Lessig, “Shipbuilder Lends a Hand with Rise of Robot Submarines,” Defense News, May 26,
2019.
36 Source: Boeing product sheet on Echo Voyager, accessed May 31, 2019, at https://www.boeing.com/resources/
boeingdotcom/defense/autonomous-systems/echo-voyager/echo_voyager_product_sheet.pdf.
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Figure 8. Boeing Echo Voyager UUV

Source: Boeing photograph posted at https://www.boeing.com/defense/autonomous-systems/echo-voyager/
index.page#/gallery.
Figure 9. Boeing Echo Voyager UUV

Source: Navy briefing entitled “Unmanned Maritime Systems,” Howard Berkof, Deputy Program Manager,
Unmanned Maritime Systems, PMS 406, Distribution A: Approved for public release; distribution unlimited,
October 23, 2019, slide 5.
The Navy states that the XLUUV
is based off Boeing’s Echo Voyager, but incorporates significant changes to support
military mission requirements. This has resulted in challenges in establishing the
manufacturing process, building up the industrial base, and aligning material purchases to
produce the first group of prototype vehicles. Orca represents the leading edge of
autonomous maritime vehicle technology and will have extended range and a
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reconfigurable, modular payload bay to support multiple payloads and a variety of
missions.37
Issues for Congress
The Navy’s proposals for developing and procuring the large UVs covered in this report pose a
number of oversight issues for Congress, including those discussed below.
Analytical Basis for Fleet Architecture Including Large UVs
One potential oversight issue for Congress concerns the analytical basis for the Navy’s desire to
shift to a more distributed fleet architecture that includes large UVs. Potential oversight questions
for Congress include the following:
 What analyses led to the Navy’s decision to shift toward a more distributed
architecture that includes large UVs?
 What did these analyses reveal about the comparative costs, capabilities, and
risks of more distributed architectures that do not include large UVs?
 How well developed and tested are the operational concepts associated with the
various options for more distributed architectures that have been analyzed?
As discussed earlier, the Navy is conducting an analysis of alternatives (AOA), which Navy
officials reportedly expected to complete by the end of April 2022, to compare the cost-
effectiveness of the LUSV to a range of alternative surface platforms, including modified naval
vessel designs such as amphibious ships, expeditionary fast transport (EPF) ships, and
expeditionary sea base (ESB) ships, modified commercial vessel designs such as container ships
and bulk carriers, new naval vessel designs, and new commercial vessel designs.
Concept of Operations (CONOPS)
Overview
Another potential oversight issue for Congress concerns the Navy’s concept of operations
(CONOPS) for these large UVs, meaning the Navy’s understanding at a detailed level of how it
will operate and support these UVs in conjunction with manned Navy ships in both combat
operations and at other times, and consequently how, exactly, these UVs will fit into the Navy’s
overall force structure and operations.
December 2021 Blog Posts
Some observers have raised questions regarding the Navy’s CONOPs for operating and
supporting large UVs, particularly large USVs. A December 10, 2021, blog post, for example,
states
The U.S. Navy is moving forward with its plans for a more distributed fleet in which
intelligent unmanned or autonomous platforms will play a significant role. Unfortunately,

37 Statement of Fredrick J. Stefany, Acting Assistant Secretary of the Navy for Research, Development and Acquisition
(ASN [RD&A]) and Vice Admiral James W. Kilby, Deputy Chief of Naval Operations for Warfare Systems and
Lieutenant General Eric M. Smith, Deputy Commandant Combat Development and Integration & Commanding
General, Marine Corps Combat Development Command, before the House Armed Services Committee Subcommittee
on Seapower and Projection Forces, on Department of the Navy Unmanned Systems, March 18, 2021, p. 12.
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many of the details about these novel systems are left to the imagination—often a poor
substitute for filling in the blanks. It may be that the blanks cannot be satisfactorily filled
when describing the infrastructure for sustaining these unmanned systems. Rightly or
wrongly, the Navy focuses most of its discussion on the direct offensive contributions of
unmanned systems for combat with major powers on warfighting impact and metrics such
as effects on targets, capacity, and tempo. Less discussion focuses on the indirect
sustainment tasks....
Our concern ... is with offboard air, surface, and subsurface unmanned vehicles that will
operate with some degree of autonomy. It matters logistically whether these offboard
systems are expendable or recoverable because recoverable systems must not only be
launched, but also retrieved, refueled (or recharged), and maintained during the potentially
long pre-combat period....
... most of the Navy’s discussions are couched in terms of operations after bullets have
started flying, omitting details about what happens during the days, weeks, and months
before combat begins. Because of that, there is little discussion of the infrastructure to
support those pre-combat operations—infrastructure that would seem to include
“motherships” and overseas land support bases for the unmanned systems if the Navy is
employing tens to hundreds of these systems. Explanations from the Navy as to how this
will happen are sparse, and one might be excused for thinking there is no significant cost
or preparation required at all.
This leads to a fundamental tradeoff without a good solution. If the Navy wants to develop
small quantities of intelligent, precision offensive unmanned systems, then those systems
should be regarded as valuable and require their own (costly) defensive measures.
Otherwise they become effectively expendable. Conversely, if the Navy wants to
emphasize quantity over quality with inexpensive mass (such as “swarms”), it needs to
recognize that there is great advantage to the side that owns the nearby land where even
larger quantities of such unmanned systems can be generated. In swarm warfare, quantity
trumps quality. Either way, there is an infrastructure tail that cannot be ignored....
The Navy can sustain small numbers of unmanned systems today. If that is the future that
the Navy envisions, with only small quantities of systems that may be superb in quality
and capability, it should say so. But the illusion created by the Navy’s strategy, whether
intentional or not, is that the number of offboard unmanned systems in use will not be
small. Furthermore, unless the offboard systems have exceedingly long range and
endurance, launching and recovering them must be done with some proximity to their
operational locations, presumably at risk of attack from the adversary.
This begs the question: What part of the Navy force structure and budget will be used for
large-scale sustainment of unmanned systems at sea? There are some possibilities, but none
look particularly attractive....
Unmanned or autonomous platforms have some roles to play (especially in surveillance
and reconnaissance), but the quantities that are required for naval operations must be
married with a sustainment plan—and maybe a shipbuilding plan—to support that level of
operations both during combat and in the days, weeks, and months before combat
operations ratchet up. A meaningful concept of operations must address this.38
A December 28, 2021, blog post states
Two subjects are nearly inescapable in commentary about the U.S. Navy today. The first
is the much-maligned, 15-year saga of the littoral combat ship (LCS), which has provided

38 Gregory V. Cox, “The U.S. Navy’s Plans for Unmanned and Autonomous Systems Leave Too Much Unexplained,”
War on the Rocks, December 10, 2021.
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an unfortunate case study for interest group capture, misalignment of ends and means, cost
overruns, and engineering failures.
The second subject is more hopeful: proposals for unmanned surface vessels that will
deliver cost savings and increase the size of the fleet....
Very little commentary, however, explicitly connects the two subjects. This is unfortunate
because, while the LCS is not unmanned, it is further on the unmanned spectrum than any
other U.S. Navy vessel in operational use, making it the closest real-world test case for
future surface fleet architecture....
... replacing sailors [on the LCS] with technology reduced maintenance at the operator
level, but increased it at the regional maintenance center and original equipment
manufacturer levels. This raised costs overall, meaning fewer platforms could be
purchased. Second, minimal manning made platforms less resilient. Fewer sailors meant
fewer problems spotted, and less capacity to fix them while underway. Hence, if fielded in
anything approximating combat conditions, the LCS would not remain effective for long.
We argue that these two challenges are as—if not more—likely to occur on unmanned
ships as they did on minimally manned ones....
Through direct experience operating their equipment while underway, LCS sailors have
developed “tribal knowledge” of their systems. They have also acquired onsite knowledge
by observing contractors and regional maintenance center engineers. As sailors transition
to shore tours at regional maintenance facilities and training groups, designing programs
to train the next generation of LCS sailors, the Navy achieves some self-sufficiency, an
experiential economy of scale that can help recoup the costs of overreliance on original
equipment manufacturers and contractors.
Yet it is difficult to see how this optimistic scenario could occur with fully unmanned
platforms. First, with no sailors aboard, the underway experimentation and practice that
produced tribal knowledge in the LCS case can’t happen. Nor will sailors be present to
observe and learn from contractors who repair equipment. Without the economy of scale
that began developing in the LCS case, maintenance costs will remain beholden to third-
party contractors.
Second, while contractors can fly out to a manned platform that is underway, they cannot
do so for an unmanned vessel. Without accommodations and life-support systems,
unmanned vessels will have to return to port for repairs, or else be sustained at sea and in
theater by amphibious ships, submarines, or expeditionary sea bases....
The minimal-manning construct of the LCS undermined its utility for distributed maritime
operations in two ways. First, removing humans from the ship placed higher demands on
contractor support. This drove up production and life-cycle costs, driving down the
quantity of platforms that could be purchased. Second, the platform’s minimal manning
made it less resilient to routine wear and tear, and consequently, the Navy both
decommissioned four LCS hulls early and had to withdraw others from routine operations
repeatedly to conduct repairs. We conclude with three recommendations to help future
unmanned surface vessels avoid a similar fate.
First, unmanned system development requires a different approach to project management
than was used for the LCS....
... unlike with the LCS, where adding personnel to the original manning concept helped
resolve failed integration points, fully unmanned platforms will lack this backstop. As a
result, there is an even higher premium on ensuring that the integration points of the ship’s
networks and mechanical systems function properly before widespread fielding. Agile
project management, a development style based on shorter timelines and multiple delivery
dates, might help address the issue. The Navy’s program executive office, Integrated
Warfare Systems, is currently working to incorporate agile continuous delivery processes.
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In this approach, the product timeline is less definitive, changes to the product are frequent
and expected, and the end user helps guide each iteration. The shipbuilding version of this
would include the use of land-based testing sites, as it will for the Navy’s new
Constellation-class frigate....39
Second, even with perfect equipment, unmanned vessels will face attacks with a
redundancy chain that is always one link shorter than it would be with sailors present....
With a distributed fleet architecture, the Navy should only use unmanned vessels for those
mission areas where the ability to survive the first few salvos matters little to the extended
fight.
Third, while purchasing and fielding a great number of vessels is necessary for distributed
maritime operations, so is preventing them all from being sunk outright. Unmanned vessels
should not be considered expendable if they are expected to provide quantity, so some
proportion of them will have to be repaired in combat conditions.... This suggests that, if
future fleet architecture depends heavily on unmanned vessels, the Navy will eventually
bear the costs of more manned support vessels as well.40
Navy Efforts to Develop CONOPs
As mentioned earlier, in May 2019, the Navy established a surface development squadron to help
develop operational concepts for LUSVs and MUSVs. The squadron was initially to consist of a
Zumwalt (DDG-1000) class destroyer and one Sea Hunter prototype medium displacement USV.
A second Sea Hunter prototype reportedly was to be added around the end of FY2020, and
LUSVs and MUSVs would then be added as they become available.41 A September 9, 2020, press
report states
Development squadrons working with unmanned underwater and surface vehicles are
moving out quickly to develop concepts of operations and human-machine interfaces, even
as they’re still using prototypes ahead of the delivery of fleet USVs and UUVs, officials
said this week.
Capt. Hank Adams, the commodore of Surface Development Squadron One
(SURFDEVRON), is planning an upcoming weeks-long experiment with sailors in an
unmanned operations center (UOC) ashore commanding and controlling an Overlord USV
that the Navy hasn’t even taken ownership of from the Pentagon, in a bid to get a head start
on figuring out what the command and control process looks like and what the supervisory
control system must allow sailors to do.
And Cmdr. Rob Patchin, commanding officer of Unmanned Undersea Vehicles Squadron
One (UUVRON-1), is pushing the limits of his test vehicles to send the program office a
list of vehicle behaviors that his operators need their UUVs to have that the commercial
prototypes today don’t have.
The two spoke during a panel at the Association for Unmanned Vehicle Systems
International (AUVSI) annual defense conference on Tuesday, and made clear that they

39 For more on the Constellation-class frigate program, see CRS Report R44972, Navy Constellation (FFG-62) Class
Frigate Program: Background and Issues for Congress
, by Ronald O'Rourke.
40 Jonathan Panter and Johnathan Falcone, “The Unplanned Costs of an Unmanned Fleet,” War on the Rocks,
December 28, 2021.
41 See, for example, Megan Eckstein, “Navy Stands Up Surface Development Squadron for DDG-1000, Unmanned
Experimentation,” USNI News, May 22, 2019; David B. Larter, “With Billions Planned in Funding, the US Navy
Charts Its Unmanned Future,” Defense News, May 6, 2019. See also Michael Fabey, “USN Seeks Path for Unmanned
Systems Operational Concepts,” Jane’s Navy International, May 16, 2019.
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want to have the fleet trained and ready to start using UUVs and USVs when industry is
ready to deliver them.42
An October 30, 2020, press report stated
The Navy is set to complete and release a concept of operations for the medium and large
unmanned surface vehicles in “the next few months,” a Navy spokesman told Inside
Defense.
Alan Baribeau, a spokesman for Naval Sea Systems Command, said the Navy extended
the due date to allow for more flexibility during the COVID-19 pandemic and allow for
sufficient time for review and staffing….
The CONOPS is currently undergoing flag-level review after completing action officer-
level review as well as O6-level review, Baribeau said.43
A December 15, 2021, press report stated
The Navy has announced new plans for a “purpose-built” facility at its warfare center in
Port Hueneme, Calif., dedicated to testing its latest unmanned surface and subsurface
vehicles.
“These facilities will be the focal point of Navy learning and experimentation on the
capabilities, operations and sustainment of unmanned maritime vehicle prototypes to
inform future programs,” Capt. Pete Small, the Navy officer leading the program office for
unmanned maritime systems, said in a Dec. 14 statement.
Some of the systems in Small’s portfolio that are destined for Port Heuenme include the
Extra Large Unmanned Undersea Vehicle (XLUUV), as well as prototypes for the Medium
and Large Unmanned Surface Vehicles.44
A May 16, 2022, press report stated
The Pacific Fleet has stood up Unmanned Surface Vessel Division One to expedite the
integration of unmanned surface vessels.
The unit will manage unmanned surface vessel experimentation for medium and large
unmanned surface vessels like the Sea Hunter and the Sea Hawk, both of which will
participate in anti-submarine warfare missions. The Pacific Fleet’s Naval Surface Force
held a ceremony May 13 establishing the command at Naval Base San Diego.
“To meet the challenges of the 21st Century, we must continue to innovate the surface
force,” Cmdr. Jeremiah Daley, the commanding officer of the unit, said in a Navy news
release. “USVDIV One will accelerate the delivery of credible and reliable unmanned
systems in conjunction with increasingly capable manned platforms into the fleet.”
Vice Adm. Roy Kitchener, commander of Naval Surface Forces, was also present at the
ceremony and described the command as a “catalyst for innovation as we employ
unmanned surface capabilities in the Pacific Fleet.”
“The implementation of unmanned systems will increase decision speed and lethality to
enhance our warfighting advantage,” Kitchener said.
The creation of the division follows the Navy’s first fleet exercise for unmanned systems
on the West Coast, called “Unmanned Integrated Battle Problem 21,” last year. Both the

42 Megan Eckstein, “USV, UUV Squadrons Testing Out Concepts Ahead of Delivery of Their Vehicles,” USNI News,
September 9, 2020.
43 Aidan Quigley, “Navy Finishing Unmanned Surface Vehicles Concept of Operations ‘in Next Few Months,’” Inside
Defense
, October 30, 2020.
44 Justin Katz, “Navy Starts Building Hub for Surface, Subsurface Drones,” Breaking Defense, December 15, 2021.
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Sea Hunter and the Sea Hawk were involved in the April 2021 exercise, however, the Navy
remained tight-lipped about specifics.
Rear Adm. Jim Aiken, who oversaw the exercise, told reporters such details were classified
and related to intelligence, surveillance and reconnaissance. However, he did share that
one scenario in the exercise required drones to extend the sight of a warship to shoot a
missile from long range.
More recently, U.S. 5th Fleet hosted International Maritime Exercise 2022 and Cutlass
Express 2022 in January and February, combined exercises that included 9,000 personnel,
50 ships and approximately 80 unmanned systems from 60 regional navies. The exercises
was designed to advance experimentation with unmanned vehicles and artificial
intelligence.45
A September 14, 2022, press report states
The U.S. Navy managed to retrieve a trio of unmanned vessels from Iranian would-be
thieves recently, but the incidents highlight the need to protect maritime drones that may
in the future be valuable, armed, or sensitive.
In the span of a week, Iranian forces tried to steal U.S. unmanned surface vessels in the
Persian Gulf and Red Sea, and in both instances U.S. helicopters and ships stopped the
Iranians and retrieved the drones. The 5th Fleet’s Task Force 59 is using these Saildrone
Explorers as part of its experimentation into how to incorporate unmanned vessels into
fleet operations ... .
This was also not the first time that a U.S. naval drone has been captured. In 2016, China
took an “ocean glider,” an underwater drone that was being used by an oceanographic ship
in international waters near the Philippines. China returned the drone several days later.
As this technology becomes more prevalent at sea, the Navy will need to consider how it
will respond in similar circumstances. The recent incidents with Iran and the Navy’s
experimental task force raised some of those questions in this “real-world test,” said Peter
Singer, a strategist at New America and author of “Ghost Fleet.”
“What do you do if an adversary harasses your system or even tries to take them? What are
your best responses? What are the lines that are uncrossable, crossable, etc.,” he said. “With
a future system you may have [classified systems], and so you're going to have to work out
like why I'd want to protect them. But then there’s the ‘Okay, how do I ensure if I lose the
system, that the enemy doesn't get any kind of advantage from it?”
Chief of Naval Operations Adm. Mike Gilday appeared to agree with that sentiment
Wednesday, saying the Navy is learning from what is happening to these drones.
“Well, we did have a response plan and we actually put it into effect when the Iranians
grabbed two of those Saildrones,” Gilday said. “That is going to be a challenge for us
though, I will say, in the future ... We’re learning from what happened over the past month
in the Middle East and we’ll be applying that as we design and grow” the unmanned surface
fleet.
Gilday said the Navy might make larger unmanned vessels “initially minimally manned”
and part of a group of ships like a carrier strike group or an amphibious ready group, “so
they wouldn’t be out there alone and unafraid, if you will.”
In a statement to Defense One, a Navy official said the service follows international law in
the operation of all its platforms at sea, “including the obligation to operate with due regard
for the rights of other states. We expect other nations to do the same. Our policy and

45 Diana Stancy Correll, “Navy Creates Unmanned Surface Vessel Division to Expedite Integration of Unmanned
Systems,” Defense News, May 16, 2022. See also Joshua Emerson Smith and Andrew Dyer, “Navy ramps up research
and development of unmanned war vessels,” San Diego Union-Tribune, May 16, 2022.
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procedures for defending unmanned systems against unlawful uses of force are the same
as those applicable to defending any U.S. property at sea.”
If the Navy wants to use their drones, especially spread out across large distances, they will
have to accept that some will be lost, said Bryan Clark, a senior fellow at the Hudson
Institute.
“If you were looking at this in the Indo-Pacific, you know, if this was the South China Sea,
then these Saildrones would be operating far enough away where you wouldn't be able to
get to them before the Chinese can take them and drag them off to one of their islands or
back home to China,” Clark said. “So it seems like you try to operate in a more distributed
manner, if you really want to exploit these vehicles, you're going to have to accept the fact
that they are going to periodically get captured or lost.”
Perhaps some of the bigger questions to contend with in the future of unmanned technology
is not the drones themselves but the actions of humans, Singer said.
“Like how much of this is actually a technology problem and how much of it is certain
states just not respecting the norms of behavior at sea, and us not having a good response
for it, whether it’s manned or unmanned,” he said....
One of the ways the Navy can protect the technology on the drones is to have tamper-
resistant features that would disable hardware or erase software to ensure no one could use
important parts, Clark said. However, the person probably would still be able to get at the
basic drone functions like its engine.
Another way may be to place sailors on the larger drone ships for periods of time to defend
it if a warship is not close enough to respond, Clark said.
“Because otherwise they just sort of take up a destroyer guarding an unmanned vessel, as
opposed to letting the destroyer do its job,” he said.46
A September 29, 2022, press report states
Twice in the last month, Iran has attempted to abduct US unmanned surface vessels
produced by Saildrone. But the company’s CEO says he was unfazed by the events, instead
calling the experience “valuable” and stressing the need for any organization operating
unmanned ships to be anticipate hostile interference.
“It’s incredibly valuable experience to truly understand what happens in the field with real
adversaries,” Richard Jenkins told Breaking Defense in a Sept. 21 interview. “Whether
that’s an actual country, whether it’s just a hurricane or a physical adversary, you have to
experience it to understand the features.”
“And if someone takes it, good luck. Keep it, it’s worthless. We’ve got hundreds of them,”
he added.
The company’s eponymously named USV became the subject of headlines in late August
and September when Iranian navy and paramilitary personnel twice attempted to confiscate
drones while they were operating in the Middle East. In both cases, the USVs were
ultimately recovered by the US Navy.
In statements following each incident, US Navy officials said the Saildrones were
“unarmed and taking unclassified” photos of the environment when the Iranians
approached. And to Jenkins, that the drones didn’t possess anything of value is a feature,
not a bug of the product.

46 Caitlin M. Kenney, “Iran’s Attempted Drone Thefts Highlight Challenges of Protecting Unmanned Vessels at Sea,”
Defense One, September 14, 2022.
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“You have to plan ahead so that there is no classified information… no security breach, IP
leak that the person who stole it could glean from” the vessel, he said. “I think it’d be a
very different problem if you had a lot of [Vertical Launch Systems] or other hardware
onboard. I think as soon as you weaponize unmanned systems, you actually make it a target
of theft.”
If a drone is stolen or destroyed, Jenkins said his company simply deploys another to
replace it.47
An October 17, 2022, press report stated
“The drones retain nothing of intrinsic value on them. This is part of one of the beauties of
American technology. There is nothing classified or written on the platform. What is
retained is minimal, and it’s all unclassified. So there’s no intrinsic value to get in these
platforms,” Vice Adm. Brad Cooper, commander of 5th Fleet, told reporters during a media
roundtable on Oct. 12....
... he underscored the Navy is likely going to stick with the current model where the USVs
do not retain any information they gather, but rather immediately relay it elsewhere,
limiting the value from stealing them.48
Potential Oversight Questions
Potential oversight questions for Congress include the following:
 How fully has the Navy developed its CONOPS for these large UVs? What
activities is the Navy undertaking to develop its CONOPS for them?
 What is the Navy’s CONOPS for operating and sustaining these large UVs,
including both combat operations and day-to-day, noncombat operations?
 How sensitive are the performance requirements that the Navy has established
for these large UVs to potential changes in their CONOPS that may occur as the
Navy continues to develop the CONOPS? How likely is it, if at all, that the Navy
will have to change the performance requirements for these large UVs as a
consequence of more fully developing their CONOPS? How do the Navy’s
acquisition strategies for these large UVs address the possibility that the UVs’
performance requirements might need to evolve as the CONOPs are developed?
Acquisition Strategies and Technical, Schedule, and Cost Risk
Overview
Another potential oversight issue for Congress concerns the amount of technical, schedule, and
cost risk in these programs, particularly given that these platforms potentially are to operate at sea
unmanned and semi-autonomously or autonomously for extended periods of time, and the
acquisition strategies that the Navy wants to use for these programs. Potential oversight questions
for Congress include the following:
 How much technical, schedule, and cost risk of this kind do these programs pose,
particularly given the enabling technologies that need to be developed for them?

47 Justin Katz, “Saildrone CEO Says Iranian Interference Was Valuable Experience, Not a Surprise,” Breaking Defense,
September 29, 2022.
48 Rich Abott, “5th Fleet USVs Keep Unclassified Tech, ‘No Intrinsic Value’ To Limit Capture Damage,” Defense
Daily
, October 17, 2022.
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 Are the Navy’s risk-mitigation and risk-management efforts for these programs
appropriate and sufficient? Are the Navy’s proposed changes to the LUSV’s
acquisition strategy appropriate and sufficient in terms of complying with
Congress’s legislative provisions and providing enough time to develop
operational concepts and key technologies before entering into serial production
of deployable units?
 At what point would technical problems, schedule delays, or cost growth in these
programs require a reassessment of the Navy’s plan to shift from the current fleet
architecture to a more distributed architecture?
 To what degree, if any, can these large UV programs contribute to new
approaches for defense acquisition that are intended to respond to the new
international security environment?
April 2022 GAO Report
An April 2022 Government Accountability Office (GAO) report on uncrewed maritime systems
(i.e., Navy UVs) stated
While the Navy’s shipbuilding plan outlines spending more than $4 billion on uncrewed
systems over the next 5 years, its plan does not account for the full costs to develop and
operate these systems.
Once conceived, the Navy must build these vehicles with the information technology and
the artificial intelligence capabilities needed to replace crews. While the Navy has
established strategic objectives for these efforts, it has not established a management
approach that orients its individual uncrewed maritime efforts toward achieving these
objectives. As such, the Navy is not measuring its progress, such as building the robust
information technology needed to operate the vehicles. GAO has previously found that
portfolio management—a disciplined process that ensures new investments are aligned
with an organization’s strategic needs within available resources—enables agencies to
implement strategic objectives and manage investments collectively. However, if it
continues with its current approach, the Navy is less likely to achieve its objectives. In
addition, the Navy has yet to:
• establish criteria to evaluate prototypes and
• develop improved schedules for prototype efforts.
With detailed planning, prototyping has the potential to further technology development
and reduce acquisition risk before the Navy makes significant investments. Since uncrewed
systems are key to the Navy’s future, optimizing the prototyping phase of this effort is
necessary to efficiently gaining information to support future decisions.49
Press Reports and Blog Post
A January 28, 2022, press report stated
The U.S. Navy is unlikely to pursue a formal program for unmanned surface vessels in the
next five years, instead focusing on the enabling technologies first, several leaders said this
month.
The Navy in fiscal 2020 laid out an aggressive plan to buy a handful of prototype medium
and large USVs and then quickly transition into a program of record using shipbuilding

49 Government Accountability Office, Uncrewed Maritime Systems[:] Navy Should Improve Its Approach to Maximize
Early Investments
, GAO-22-104567, April 2022, highlights page (PDF page 2 of 54).
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funds. The service acknowledged it would adjust the program-of-record USV design over
time to incorporate lessons learned as prototypes hit the water.
Leaders argued this strategy was necessary because the technology was key to the Navy’s
Distributed Maritime Operations concept, and because there was no time to waste in
building and fielding the vessels.
After two years of Congress pushing back against this quick move into unmanned
programs, the Navy has quietly acknowledged a change in strategy.
“We are focused on prototyping and maturing the fundamentals, the building blocks,” Rear
Adm. Casey Moton, the program executive officer for unmanned and small combatants,
said earlier this month at the Surface Navy Association’s [SNA’s] annual conference.
Though Moton said there’s a lot of interest in the future large and medium USV
programs—previously slated to begin as early as 2023—his team is more “focused on the
system engineering pillars that we need to field any such platform.”...
Rear Adm. Paul Schlise, the director of surface warfare on the chief of naval operations’
staff (OPNAV N96), told Defense News following his presentation at a separate SNA panel
that he wouldn’t move into a program of record until all those separate pillars were more
mature. One key pillar is the development and maturation of hull, mechanical and electrical
systems that can support unmanned vessel operations.
Schlise said lawmakers were “crystal clear” in the fiscal 2021 defense authorization bill
that they didn’t want to invest in programs of record until it’s clear hull, mechanical and
electrical systems would work for weeks or months at a time without sailors around to
perform routine maintenance or emergency repairs....
Asked how long that would take and when the Navy will begin a program of record, Schlise
said he hopes by the end of the five-year Future Years Defense Program that the service
will “have gotten pretty confident in what we can and can’t do. And maybe we’ll learn this
is going to take a little bit longer. I don’t have an absolute clairvoyant picture.”50
A February 16, 2022, press report stated
Aircraft carriers will deploy alongside large unmanned vessels within five years, if the
Navy’s top officer gets his way.
In 2027 or 2028—“and earlier if I can”—Adm. Mike Gilday said he wants to begin to
deploy large and medium-sized unmanned vessels as part of carrier strike groups and
amphibious ready groups.
For the first deployments, such vessels “may not necessarily be completely unmanned; they
may be minimally manned,” the chief of naval operations told reporters in a Wednesday
[February 16] conference call. “But I want to be in a position where we can crawl-walk-
run” and “put us in a position where we can scale [i.e., increase the numbers of these UVs]
in the 2030s.”
One key to this, Gilday said, is doing as much testing and prototyping as possible at land-
based facilities and simulators....
Another vital component, Gilday said, are the flexible and reliable wireless networks that
will connect uncrewed vessels to the rest of a strike group.51
Another February 16, 2022, press report states

50 Megan Eckstein, “US Navy Adopts New Strategy Prioritizing ‘the Building Blocks’ of Unmanned Tech,” Defense
News
, January 28, 2022.
51 Bradley Peniston, “Navy Chief Sees Robot Ships Alongside Aircraft Carriers Within Five Years,” Defense One,
February 16, 2022.
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“We’re moving in an evolutionary instead of a revolutionary manner, in order to deliver a
platform [that] is going to be reliable and that’s actually going to perform as intended,”
[Chief of Naval Operations Admiral Mike] Gilday said [February 16]. “We could actually
learn greatly from our land-based engineering test sites … specifically up in Philadelphia,
Pennsylvania, where we can take an engineering configuration that we want to use on a
specific platform.”
While the Navy is proving those systems to Congress, Gilday wants to get other types of
smaller vehicles into the fleet sooner....
While the mechanical reliability of the platforms is a major point of concern, so are the
networks that transmit the targeting data. The service plans to use its existing networks to
transmit surveillance data and targeting information the same way a smartphones
transitions from lower to different networks as a user moves from Wi-Fi to a cellular data
network.
“The software on the phone shifts you to a [cell] network automatically. You don’t care,
the phone doesn’t care, you’re just getting, you’re just getting the information you want
when you want it. It’s that same type of idea where software would decide,” Gilday said.
“The system would then containerize it in a way that could ride on any one of those
lightning bolts. It could move on any one of those systems to get to the endpoint system.
It’s leveraging the fact that every shooter doesn’t necessarily have to sense the target that
you’re going to that it is going to fire at. That it can be set the target it can be… radio
silent.”
The Navy has tested the software-defined system in San Diego and Gilday said there are
plans to test a battle group with the concept later this year or in early 2023.
The new tack from the Navy will get new unmanned systems to the fleet faster and inform
the larger systems that are developing more slowly.
“We thought that was important, or I thought that was important from a risk-reduction
standpoint so that we could begin to mature and then hopefully scale unmanned capabilities
at a faster pace,” he said.52
A March 10, 2022, press report stated
Public discussions between the Navy and Congress over unmanned technology in recent
years have been circular: The service asks for funding to develop new technology, hesitant
lawmakers balk at pouring millions into unproven tech, then the Navy re-ups its requests
the next year, insistent the investment remains necessary.
The routine has left Congress wary of the Navy’s ideas and the service struggling to refine
its pitch.
But during a year filled with international exercises, with a new task force stood up by the
chief of naval operations and amid significant programmatic advances, the Navy hopes to
break the cycle by changing its messaging strategy around unmanned systems: More
showing, less telling.
It’s a slow shift, but analysts told Breaking Defense there are signs that the Navy has taken
cues on what it will take to sway opinions in Congress towards backing more aggressive
funding of unmanned technology.
“I think the new strategy by the Navy to focus on the core enabling technologies is the right
strategy. [It] will bring about that comfort level from Congress that will enable the funding
and allow industry to begin to scale these programs working hand in glove with the Navy,”

52 Sam LaGrone, “CNO Gilday Taking a More ‘Realistic’ Approach to Unmanned Systems in the Fleet,” USNI News,
February 16 (updated February 17), 2022.
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said Michael Robbins, a spokesman for the Association for Uncrewed Vehicles Systems
International, a non-profit group focused on promoting unmanned systems technology.
Recently Chief of Naval Operations Adm. Michael Gilday acknowledged that the Navy
took lessons from past missteps.
“I think we’ve learned a lot, as I said, from those other classes of ships. I think that
Congress is holding our feet to the fire on those lessons, and I’m 100% in support of that,”
he told reporters last month.
When asked about the service’s messaging to lawmakers, Gilday highlighted Congress’
insistence on land-based testing, a process in which the Navy attempts to install and operate
a new technology ashore before tampering with an operational warship. It’s a simple
concept, but the Navy has infuriated lawmakers in the past when expensive programs
suffered costly setbacks after skipping this step.
The Navy has learned the importance of “moving in an evolutionary, instead of a
revolutionary, manner in order to deliver a platform and it’s going to be reliable and its
actually going to perform as intended,” he said.
In other words, small changes with proven results over time are going to instill more
confidence in lawmakers than grand proposals with questionable visions....
Opinions about unmanned technology, like any issue in Washington, DC, are not uniform
on Capitol Hill. But the budget cuts and restrictive language in the last handful of National
Defense Authorization Acts show that lawmakers have been erring on the side of caution
when pitched on the biggest projects the Navy proposes.
The most ambitious efforts have usually been predicated more so on promises from service
leadership rather than proven results, lawmakers complain.
“For a long time, unmanned has been the promise of the future that will always remain in
the future. And that’s just where we are right now,” said Chris Brose, formerly the staff
director on the Senate Armed Services Committee and current chief strategy officer of the
defense contractor Anduril. “The new prioritization of trying to get capability out to the
fleet fast to solve problems that unmanned systems can solve now… That to me is just a
welcome improvement.”
For example, in just the past year, the service has established two task forces focused on
unmanned technology: one at the CNO’s level and one based at US 5th Fleet based in
Bahrain. The Strategic Capabilities Office has transferred ownership of a flagship
unmanned surface vessel program to the Navy’s fleet. And the service has also publicized
a variety of international exercises featuring unmanned US assets.
That is not an exhaustive list of Navy unmanned activities, but they are some of the more
public events the service has flaunted in recent months to get its message across to the
public and lawmakers.
“The Navy has been really focused on fielding entire systems using programs of record to
move large projects forward and that’s received… significant push back from Congress,”
said Robbins.
“What we’re hearing now is a different strategy from the Navy that is focused, not so much
on programs of record, but instead focusing on the various enabling technologies to build
these programs. I think that is a direct result of feedback from Congress,” he continued.53

53 Justin Katz, “Show, Don’t Tell: Navy Changes Strategy to Sell Unmanned Systems to Skeptical Congress,” Breaking
Defense
, March 10, 2022. See also Megan Eckstein, “Unmanned or Minimally Manned Vessels Could Deploy
Alongside Strike Groups as Soon as 2027,” Defense News, February 17, 2022; Justin Katz, “From 7 Classified ‘Spirals’
to Coming Robotic Ships: Gilday on Navy’s Unmanned Task Force,” Breaking Defense, February 17, 2022.
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A June 14, 2022, press report states
Boeing Co. is expected to deliver Orca—an underwater drone the size of a subway car
that’s envisioned to lay mines and perform other missions for the US Navy—as much as
three years later than planned.
As the Navy works to incorporate pilotless ships in its future fleet, budget documents show
the first of five operational Orca drones may be delivered in September 2023, rather than
December 2020, “due to contractor challenges and supplier issues.”...
“The Navy is working with Boeing to mitigate schedule delays and execute risk reduction”
by paying for a prototype that’s being used for testing and training, the service said. The
test drone was christened April 28 and began its first in-water testing....
Boeing has “worked diligently to stand up a new industrial base and supply chain for
titanium composites, pressure vessel manufacturing” at efficient production rates and
“batteries necessary to enter production” on the Orca system, the Naval Sea Systems
Command said in a statement.
The command didn’t address why these production challenges weren’t anticipated before
Boeing’s award over Lockheed. Nor did it address what cost growth the delays and
production issues have caused....
Orca’s technical issues are likely to be repeated as the service pursues unmanned systems,
according to Shelby Oakley, a Government Accountability Office acquisition director who
has followed the issue. “The Navy is in the beginning phases of developing uncrewed
systems and, like all new technical endeavors, is likely to face some challenges,” she said.
“The Navy can improve the development by changing its management approach and better
planning its strategy for transitioning its prototyping efforts,” she said. “We are currently
in the process of reviewing the challenges facing” the Orca program “and plan to report on
the Navy’s path forward this summer.”54
A June 24, 2022, blog post states
As the U.S. Navy pivots to autonomous technologies for its future hybrid fleet of crewed
and uncrewed ships, defense professionals and military officers (inspired in no small part
by the novels Ghost Fleet and 2034) are keenly aware that every automated system is at
risk of intrusion. The focus on cyber attacks, however, obscures a more fundamental cyber
reliability problem. When computers replace people in the role of monitoring engineering
systems, identifying equipment failures becomes more difficult. Leaving those problems
unfixed makes vessels fail earlier, and fixing them puts ships and people at risk. In short,
automated systems can introduce system-wide vulnerability even if nobody hacks them.
Uncrewed vessels will require computers and internal networks to control and monitor hull,
mechanical, and electrical systems. Critically, these systems—especially those managing
the electrical power generation and cooling—will themselves power the computers and
networks monitoring them. Without human operators to identify or fix potential points of
failure early, small problems may compound, triggering feedback loops. Moreover,
uncrewed systems will require near-real-time off-ship communications for command and
control, and for monitoring how equipment failures impact the overall force’s readiness.
Combined with uncrewed vessels’ expected role as forward sensors, this will make them
persistent radiofrequency emitters, exposing them and nearby units to enemy surveillance
and targeting.
Integrating hull, mechanical, and electrical systems with computerized controls is therefore
an inherent obstacle to achieving a high-endurance, hybrid fleet resilient to cyber attacks,

54 Anthony Capaccio and Julie Johnsson, “US Navy’s Giant Underwater ‘Orca’ Drone Is Running Years Late,”
Bloomberg, June 14, 2022.
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one that will affect force structure, crisis stability, and force employment. Since uncrewed
vessels will most likely support forward sensing, mine countermeasures, and anti-
submarine warfare, these may be among the first capabilities that a future fleet loses, even
before a battle begins. In addition, since situational awareness will degrade faster than the
capacity to launch missiles for air defense, anti-surface warfare, and land attack, human
decision-makers may face pressure to expend missiles before they lose the ability to use
them. During crises, this could increase the risk of conflict. When war has started, it could
limit a commander’s flexibility....
The success of distributed maritime operations will depend on robust networks among
vessels that maintain stable propulsion, power, and cooling. But current plans to achieve
this architecture rest on an aspirational version of uncrewed vessel technology. Even with
ongoing—and well-funded—land-based testing requirements aimed at resolving reliability
problems in automated systems, some of the drawbacks associated with removing people
from ships are likely to remain long-term features of the Navy’s future hybrid fleet.
Crewed warships will thus have to fix uncrewed vessels, step in to fill their roles, or face
tough choices to employ weapons systems with incomplete information. The aspirational
vision of uncrewed technologies thus makes crewed vessels more important, at the same
time that it forces their premature retirement. And this is perhaps the most dangerous
feedback loop of all.55
Cost Growth and Schedule Delay in XLUUV Program
Another oversight issue for Congress concerns cost growth and schedule delay in the XLUUV
program. A September 2022 GAO report on the XLUUV program states
The Navy is attempting to rapidly deliver five Extra Large Unmanned Undersea Vehicles
(XLUUV) to the fleet for deploying undersea mines without the need for sailors. However,
the XLUUV effort is at least $242 million or 64 percent over its original cost estimate and
at least 3 years late. The contractor originally planned to deliver the first vehicle by
December 2020 and all five vehicles by the end of calendar year 2022. The Navy and the
contractor are in the process of revising the delivery dates. But both expect the contractor
to complete and deliver all five vehicles between February and June 2024.
The contractor did not demonstrate its readiness to fabricate XLUUV because it was not
required to do so. For acquisition programs, DOD and Navy typically conduct a production
readiness review. While XLUUV is a prototype and not an acquisition program, the Navy
plans to field the vehicles quickly. Key differences between the XLUUV and the
contractor’s prototype, the Echo Voyager, required the contractor to redesign critical
components. Rather than address issues before starting fabrication, the contractor did not
identify the full impact of these issues until after fabrication began. Then, significant delays
were exacerbated by the COVID-19 pandemic. Further, the Navy has begun assessing the
possibility of adding more capability and vehicles to this effort. If the Navy forgoes a
production readiness review for its next XLUUV purchase, it risks beginning fabrication
without information to assess the contractor’s cost, schedule, and performance targets.
The Navy determined that XLUUV was critical to fulfilling an emergent need, which,
under DOD policy, generally requires a capability be provided within 2 years. However,
the Navy did not develop a sound business case, including cost and schedule estimates, to
ensure that it could deliver the vehicles quickly to the fleet because XLUUV is a research
and development effort. According to DOD urgent capability acquisition best practices, an
acquiring organization should make cost and schedule trade-off decisions to get solutions

55 Jonathan Panter and Johnathan Falcone, “Feedback Loops and Fundamental Flaws in Autonomous Warships,” War
on the Rocks
, June 24, 2022.
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to the fleet faster. Without more complete cost and schedule estimates, the Navy does not
have the information it needs for decision-making and, thus, could continue experiencing
cost overruns and schedule delays as it builds the XLUUV.56
An October 14, 2022, press report quoted a Boeing official as stating that the company’s efforts
to stand up new manufacturing and assembly lines for the XLUUV program were “performed
during the COVID-19 pandemic, so [there were] heavy travel restrictions that we were under,
global parts and raw material shortages and then most recently, a lot of that further exacerbated
by, Russia's invasion of Ukraine.” The article quoted the official as stating that “the most
significant challenges we’ve encountered that led to the schedule delays that are driving the
program [were those associated with] our design of the new battery and the associated battery
management system” for the XLUUV compared to those used on the Boeing Echo Voyager.57
A November 29, 2022, press report stated:
[Rear Adm. Casey Moton, the program executive officer for unmanned and small
combatants] said the Orca [XLUUV] program has seen significant production delays, but
he remains confident the Navy will learn from the initial prototypes being built now and
then move into a program of record....
Moton attributed the delays in part to pandemic and post-pandemic challenges: production
delays, shortages in parts and forgings, supply chain backups for key components like
lithium ion batteries.
A Boeing spokesperson told Defense News “the Orca program is a development program
involving groundbreaking technology.”
“There is no other commercially available XLUUV anywhere,” the spokesperson added.
“Supply chain challenges combined with high quality requirements have affected timeline
and schedule. The Navy has been informed and involved in the entire development
program, including the analysis and thought process behind any delays.”
Despite the delays, Moton said Boeing is very close to achieving full integration on the test
asset system, called XLE0, which will deliver to the Navy in early 2023. Boeing said it
christened this vehicle in April and will relaunch it by the end of the year to allow for sea
trials and delivery next year.
The test asset will reduce risk on the following five Orca prototypes, the last of which GAO
says will now deliver in mid-2024.
Moton said he couldn’t discuss the timing of a program of record for Orca because that’s
part of ongoing FY24 budget negotiations. But he said the test asset and five prototypes
will give the Navy a good understanding of the XLUUV program’s anticipated cost and
schedule.58

56 Government Accountability Office, Extra Large Unmanned Undersea Vehicle[:] Navy Needs to Employ Better
Management Practices to Ensure Swift Delivery to the Fleet
, GAO-22-105974, highlights page (PDF page 2 of 31). See
also Anthony Capaccio and Julie Johnsson, “US Navy’s Giant Underwater ‘Orca’ Drone Is Running Years Late,”
Bloomberg, June 14, 2022.
57 Audrey Decker, “Boeing Says XLUUV Delays Primarily Caused by Battery Redesign,” Inside Defense, October 14,
2022.
58 Megan Eckstein, “What’s Ahead for Navy Unmanned Underwater Vehicle Programs?” Defense News, November 29,
2022.
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Industrial Base Implications
Another oversight issue for Congress concerns the potential industrial base implications of these
large UV programs as part of a shift to a more distributed fleet architecture, particularly since
UVs like these can be built and maintained by facilities other than the shipyards that currently
build the Navy’s major combatant ships. Potential oversight questions for Congress include the
following:
 What portion of these UVs might be built or maintained by facilities other than
shipyards that currently build the Navy’s major combatant ships?59
 To what degree, if any, might these large UV programs change the current
distribution of Navy shipbuilding and maintenance work, and what implications
might that have for workloads and employment levels at various production and
maintenance facilities?
Potential Implications for Miscalculation or Escalation at Sea
Another oversight issue for Congress concerns the potential implications of large UVs,
particularly large USVs, for the chance of miscalculation or escalation in when U.S. Navy forces
are operating in waters near potential adversaries. Some observers have expressed concern about
this issue. A June 28, 2019, opinion column, for example, states
The immediate danger from militarized artificial intelligence isn't hordes of killer robots,
nor the exponential pace of a new arms race.
As recent events in the Strait of Hormuz indicate, the bigger risk is the fact that autonomous
military craft make for temping targets—and increase the potential for miscalculation on
and above the high seas.
While less provocative than planes, vehicles, or ships with human crew or troops aboard,
unmanned systems are also perceived as relatively expendable. Danger arises when they
lower the threshold for military action.
It is a development with serious implications in volatile regions far beyond the Gulf—not
least the South China Sea, where the U.S. has recently confronted both China and Russia….
As autonomous systems proliferate in the air and on the ocean, [opposing] military
commanders may feel emboldened to strike these platforms, expecting lower repercussions
by avoiding the loss of human life.
Consider when Chinese naval personnel in a small boat seized an unmanned American
underwater survey glider60 in the sea approximately 100 kilometers off the Philippines in
December 2016. The winged, torpedo-shaped unit was within sight of its handlers aboard
the U.S. Navy oceanographic vessel Bowditch, who gaped in astonishment as it was
summarily hoisted aboard a Chinese warship less than a kilometer distant. The U.S.
responded with a diplomatic demarche and congressional opprobrium, and the glider was
returned within the week….
In coming years, the Chinese military will find increasingly plentiful opportunities to
intercept American autonomous systems. The 40-meter prototype trimaran Sea Hunter, an

59 For an opinion piece addressing this issue, see Collin Fox, “Distributed Manufacturing for Distributed Lethality,”
Center for International Maritime Security (CIMSEC), February 26, 2021.
60 A glider is a type of UUV. The glider in question was a few feet in length and resembled a small torpedo with a pair
of wings. For a press report about the seizure of the glider, see, for example, Sam LaGrone, “Updated: Chinese Seize
U.S. Navy Unmanned Vehicle,” USNI News, December 16, 2016.
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experimental submarine-tracking vessel, recently transited between Hawaii and San Diego
without human intervention. It has yet to be used operationally, but it is only a matter of
time before such vessels are deployed….
China’s navy may find intercepting such unmanned and unchaperoned surface vessels or
mini-submarines too tantalizing to pass up, especially if Washington’s meek retort to the
2016 glider incident is seen as an indication of American permissiveness or timidity.
With a captive vessel, persevering Chinese technicians could attempt to bypass anti-tamper
mechanisms, and if successful, proceed to siphon off communication codes or proprietary
artificial intelligence software, download navigational data or pre-programmed rules of
engagement, or probe for cyber vulnerabilities that could be exploited against similar
vehicles….
Nearly 100,000 ships transit the strategically vital Singapore Strait annually, where more
than 75 collisions or groundings occurred last year alone. In such congested international
sea lanes, declaring a foreign navy’s autonomous vessel wayward or unresponsive would
easily serve as convenient rationale for towing it into territorial waters for impoundment,
or for boarding it straightaway….
A memorandum of understanding signed five years ago by the U.S. Department of Defense
and the Chinese defense ministry, as well as the collaborative code of naval conduct created
at the 2014 Western Pacific Naval Symposium, should be updated with an expanded right-
of-way hierarchy and non-interference standards to clarify how manned ships and aircraft
should interact with their autonomous counterparts. Without such guidance, the risk of
miscalculation increases.
An incident without any immediate human presence or losses could nonetheless trigger
unexpected escalation and spark the next conflict.61
Legislative Activity for FY2023
Summary of Congressional Action on FY2023 Funding Request
Table 1
summarizes congressional action on the Navy’s FY2023 funding request for the LUSV,
MUSV, and XLUUV programs and their enabling technologies. Funding for UUV core
technologies (line 78) develops technologies for various Navy UUVs, including but not limited to
XLUUV.


61 Evan Karlik, “US-China Tensions—Unmanned Military Craft Raise Risk of War,” Nikkei Asian Review, June 28,
2019. See also David B. Larter, “The US Navy Says It’s Doing Its Best to Avoid a ‘Terminator’ Scenario in Quest for
Autonomous Weapons,” Defense News, September 12, 2019; David Axe, “Autonomous Navies Could Make War More
Likely,” National Interest, August 17, 2020.
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Table 1. Congressional Action on FY2023 Large UV Funding Request
Millions of dollars, rounded to the nearest tenth


Authorization
Appropriation
HASC-
Research and development
SASC
funding
Request HASC SASC agreement
HAC
SAC
Enacted
PE 0603178N, Large Unmanned
146.8
146.8
146.8
146.8
146.8
122.3

Surface Vessels (LUSVs) (line 28)
PE 0605512N Medium Unmanned
104.0
104.0
104.0
104.0
104.0
86.4

Surface Vehicles (MUSVs) (line 94)
PE 0605513N, Unmanned Surface
181.6
166.6
181.6
181.6
181.6
181.6

Vehicle Enabling Capabilities (line 95)
PE 0604536N, Advanced Undersea
116.9
116.9
154.3a
116.9
116.9
94.9

Prototyping (line 89) [XLUUV]
Subtotal above
549.3
534.3
586.7
549.3
549.3
485.2

PE 0604029N, UUV Core
60.7
60.7
60.7
60.7
60.7
60.7

Technologies (line 78)
TOTAL
610.0
595.0
647.4
610.0
610.0
545.9

Sources: Table prepared by CRS based on FY2023 Navy budget submission, committee and conference reports,
and explanatory statements on the FY2023 National Defense Authorization Act and the FY2023 DOD
Appropriations Act.
Notes: PE is program element (i.e., a line item in a DOD research and development account). HASC is House
Armed Services Committee; SASC is Senate Armed Services Committee; HAC is House Appropriations
Committee; SAC is Senate Appropriations Committee. Funding for UUV core technologies (line 78) develops
technologies for various Navy UUVs, including but not limited to XLUUV.
a. The SASC-recommended increase of $37.4 mil ion for line 89 is for the Mark 68 Clandestine Delivered
Mine (CDM), which is a system other than the XLUUV.
FY2023 National Defense Authorization Act (H.R. 7900/S. 4543/H.R.
7776)

House
The House Armed Services Committee, in its report (H.Rept. 117-397 of July 1, 2022) on H.R.
7900, recommended the funding levels shown in the HASC column of Table 1. The
recommended reduction of $15.0 million for line 95 is for “Program decrease.” (Page 475)
H.Rept. 117-397 states
Department of the Navy Unmanned Campaign Framework
The committee notes that the Department of the Navy’s (DoN) Unmanned Campaign
Framework serves as DoN’s holistic approach to developing and deploying unmanned
systems. As discussed in the Framework, the Navy and Marine Corps must align their
unmanned systems vision to execute Distributed Maritime Operations (DMO) and Littoral
Operations in a Contested Environment (LOCE) and, to ensure success, the Navy and
Marine Corps must tightly couple requirements, resources, and acquisition policies to
develop, build, integrate and deploy effective unmanned systems faster.
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The committee believes the current Unmanned Campaign Framework overlooks smaller
autonomous, unmanned options that can provide operationally critical payloads with
intelligence, surveillance and reconnaissance (ISR) and electronic warfare (EW) systems.
The committee believes Navy should more closely examine small, low-cost, high-
endurance, reconfigurable ships that can accommodate various payloads. These platforms
could assist the Navy in accelerating its shift to a more distributed fleet architecture that
can respond effectively to the improving maritime anti-access/area-denial (A2/AD)
capabilities of adversaries, particularly China, while leveraging advances in technologies
that enable widely distributed maritime forces that include significant numbers of UVs.
The committee believes Navy should better leverage the diversity of platforms offered by
the private sector and should use OTA acquisition strategies for small and medium UMS
programs Specifically, Navy should better access the exceptionally varied and rapidly
expanding Commercial of the Shelf (COTS) UMS platforms and service models that could
include Contactor Owned, Contractor Operated—COCO, and Government Owned,
Contractor Operated UMS (GOCO) service models. Therefore, the committee directs the
Secretary of the Navy to brief the House Committee on Armed Services by March 1, 2023
as to the Department of the Navy (DoN) latest iteration of the Unmanned Campaign
Framework including an updated acquisition strategy, plan and budget. (Page 257)
Senate
The Senate Armed Services Committee, in its report (S.Rept. 117-130 of July 18, 2022) on S.
4543, recommended the funding levels shown in the SASC column of Table 1. The
recommended increase of $37.4 million for line 89 is for “Mk68” (i.e., the Mark 68 Clandestine
Delivered Mine [CDM], which is a system other than the XLUUV).62 (Page 446)
House-Senate Agreement
The joint explanatory statement for H.R. 7776 recommended the funding levels shown in the
HASC-SASC agreement column of Table 1.
FY2023 DOD Appropriations Act (H.R. 8236/S. 4663)
House
The House Appropriations Committee, in its report (H.Rept. 117-388 of June 24, 2022) on H.R.
8236, recommended the funding levels shown in the HAC column of Table 1.
Senate
The explanatory statement for S. 4663 released by the Senate Appropriations Committee on July
28, 2022, recommended the funding levels shown in the SAC column of Table 1.
The recommended net reduction of $24.517 million for line 28 includes a recommended
reduction of $2.517 million for “LUSV acquisition documentation ahead of need,” a
recommended reduction of $32.0 million for “OUSV4 [Optionally Unmanned Surface Vessel 4]
ICS [Integrated Combat System] hardware procurement ahead of need,” and a recommended
increase of $10.0 million for “Program increase: Additive manufacturing of unmanned maritime
systems.” (Page 186)

62 For a press report about Navy programs for mines, including the Mark 68 CDM, see Megan Eckstein, “Navy Hosts
Virtual Industry Day to Keep Hammerhead Mine on Accelerated Acquisition Path,” USNI News, April 13, 2020.
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The recommended reduction of $17.557 million for line 94 includes a recommended reduction of
$13.657 million for “MUSV ship qualification testing ahead of need,” and a recommended
reduction of $3.9 million for “MUSV certification ahead of need.” (Page 187)
The recommended reduction of $22.008 million for line 89 is for “XLUUV testing delay.”
(Page 187)


Author Information

Ronald O'Rourke

Specialist in Naval Affairs



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Congressional Research Service
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