Navy Large Unmanned Surface and Undersea Vehicles: Background and Issues for Congress

Navy Large Unmanned Surface and Undersea
March 25, 2021
Vehicles: Background and Issues for Congress
Ronald O'Rourke
The Navy in FY2021 and beyond wants to develop and procure three types of large unmanned
Specialist in Naval Affairs
vehicles (UVs). These large UVs are called Large Unmanned Surface Vehicles (LUSVs),

Medium Unmanned Surface Vehicles (MUSVs), and Extra-Large Unmanned Undersea Vehicles
(XLUUVs). The Navy requested $579.9 million in FY2021 research and development funding

for these large UVs and their enabling technologies. As part of its action on the Navy’s proposed
FY2021 budget, Congress provided $238.9 million.
The Navy wants to acquire these large UVs as part of an effort to shift the Navy to a more distributed fleet architecture.
Compared to the current fleet architecture, this more distributed architecture is to include proportionately fewer large surface
combatants (i.e., cruisers and destroyers), proportionately more small surface combatants (i.e., frigates and Littoral Combat
Ships), and the addition of significant numbers of large UVs. The Navy wants to employ accelerated acquisition strategies for
procuring these large UVs, so as to get them into service more quickly. The Navy’s desire to employ these accelerated
acquisition strategies can be viewed as an expression of the urgency that the Navy attaches to fielding large UVs for meeting
future military challenges from countries such as China.
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. The Navy wants LUSVs to be low-cost, high-endurance, reconfigurable ships based on commercial ship designs, with
ample capacity for carrying various modular payloads—particularly anti-surface warfare (ASuW) and strike payloads,
meaning principally anti-ship and land-attack missiles. 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 co ncepts.
The Navy defines MUSVs as being 45 feet to 190 feet long, with displacements of roughly 500 tons . 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
acquisition authority. The first MUSV prototype was funded in FY2019 and the Navy wants fund the second prototype in
FY2023. On July 13, 2020, the Navy announced that it had awarded “a $34,999,948 contract to L3 Technologies, Inc. for the
development of a single Medium Unmanned Surface Vehicle (MUSV) prototype, with options to procure up to eight
additional MUSVs.”
The first five XLUUVs were funded in FY2019; they are being built by Boeing. The Navy wants procure additional
XLUUVs at a rate of two per year starting in FY2023. The Navy’s FY2021 budget submission did not request funding for the
procurement of additional XLUUVs in FY2021 or FY2022.
The Navy’s large UV programs pose a number of oversight issues for Congress, including issues relating to the analytical
basis for the more distributed fleet architecture; the Navy’s accelerated acquisition strategies for these programs; technical,
schedule, and cost risk in the programs; the proposed annual procurement rates for the programs; the industrial base
implications of the programs; potential implications for miscalculation or escalation at sea; the personnel implications of the
programs; and whether the Navy has accurately priced the work it is proposing to do on the programs.
In marking up the Navy’s proposed FY2020 and FY2021 budgets, some of the congressional defense committees expressed
concerns over whether the Navy’s accelerated acquisition strategies provided enough time to adequately develop concepts of
operations and key technologies for these large UVs, particularly the LUSV. In response to the markups to its FY2020
budget, the Navy’s FY2021 budget proposed modifying the acquisition strategy for the LUSV program so as to provide more
time for developing operational concepts and key technologies before entering into serial production of d eployable 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
Navy USV and UUV Categories ............................................................................. 2
Large UVs and Navy Ship Count ............................................................................ 4
Part of More Distributed Navy Fleet Architecture ...................................................... 4
Accelerated Acquisition Strategies and Enabling Technologies .................................... 6
LUSV, MUSV, and LXUUV Programs in Brief .............................................................. 8
Navy Vision and Schedule for USVs and UUVs ........................................................ 8
LUSV Program .................................................................................................... 9
MUSV Program ................................................................................................. 16
XLUUV Program ............................................................................................... 18
FY2021-FY2025 Funding.................................................................................... 20
Issues for Congress ....................................................................................................... 21
Analytical Basis for More Distributed Fleet Architecture ............................................... 21
Concept of Operations (CONOPS) ............................................................................. 21
Accelerated Acquisition Strategies and Funding Method................................................ 23
Technical, Schedule, and Cost Risk ............................................................................ 23
Annual Procurement Rates ........................................................................................ 25
Industrial Base Implications ...................................................................................... 26
Potential Implications for Miscalculation or Escalation at Sea ........................................ 26
Personnel Implications ............................................................................................. 27
Annual Funding ...................................................................................................... 28
Legislative Activity for FY2022 ...................................................................................... 28
Legislative Activity for FY2021 ...................................................................................... 28

Summary of Congressional Action on FY2021 Funding Request..................................... 28
FY2021 National Defense Authorization Act (H.R. 6395/S. 4049/P.L. 116-283) ................ 29
House ............................................................................................................... 29
Senate .............................................................................................................. 30
Conference ........................................................................................................ 36
FY2021 DOD Appropriations Act (H.R. 7617/S. XXXX/Division C of H.R. 133/P.L.
116-260) .............................................................................................................. 40
House ............................................................................................................... 40
Senate .............................................................................................................. 40
Conference ........................................................................................................ 41

Figures
Figure 1. Navy USV Systems Vision .................................................................................. 3
Figure 2. Navy UUV Systems Vision ................................................................................. 3
Figure 3. Enabling Technologies for USVs and UUVs .......................................................... 7
Figure 4. Sea Hunter Prototype Medium Displacement USV.................................................. 7

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Figure 5. Navy USV Systems Vision .................................................................................. 8
Figure 6. Navy UUV Systems Vision ................................................................................. 9
Figure 7. Prototype and Notional LUSVs and MUSVs ........................................................ 10
Figure 8. LUSV Prototype .............................................................................................. 10
Figure 9. LUSV prototype .............................................................................................. 11
Figure 10. Rendering of L3Harris Design Concept for MUSV.............................................. 17
Figure 11. Boeing Echo Voyager UUV ............................................................................. 19
Figure 12. Boeing Echo Voyager UUV ............................................................................. 20
Figure 13. Boeing Echo Voyager UUV ............................................................................. 20

Tables
Table 1. FY2021-FY2025 Requested and Programmed Funding for Large UVs ...................... 21
Table 2. Congressional Action on FY2021 Large UV Funding Request.................................. 28

Contacts
Author Information ....................................................................................................... 42

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Navy Large Unmanned Surface and Undersea Vehicles

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 FY2021 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 new fleet
architecture (i.e., a new combination of ships and other platforms) that is more widely distributed
than the Navy’s current fleet architecture. The Navy requested $579.9 mil ion in FY2021 research
and development funding for these large UVs and their enabling technologies.
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
substantial y 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
smal er USVs and UUVs, as wel 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 intel igence, and cyber capabilities—that the Navy says it is pursuing to meet
emerging military chal enges, 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.3 They can be individual y less expensive to procure

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 Report R45392, U.S. Ground Forces Robotics and
Autonom ous System s (RAS) and Artificial Intelligence (AI): Considerations for Congress
, coordinated by Andrew
Feickert .
2 See, for example, Department of the Navy, Highlights of the Department of the Navy FY 2021 Budget, inside front
cover (“T he Bottom Line”). For a CRS report on Navy lasers, electromagnetic railguns, an d the gun-launched guided
projectile (also known as the hypervelocity projectile), see CRS Report R44175, Navy Lasers, Railgun, and Gun-
Launched Guided Projectile: Background and Issues for Congress
, by Ronald O'Rourke. For a CRS report on
advanced military technologies, see CRS In Focus IF11105, Defense Prim er: Em erging Technologies, by Kelley M.
Sayler.
3 For more on autonomous UVs, see CRS In Focus IF11150, Defense Primer: U.S. Policy on Lethal Autonomous
Weapon System s
, by Kelley M. Sayler.
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than manned ships and aircraft because their designs do not need to incorporate spaces and
support equipment for onboard human operators. UVs can be 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. Consequently UVs
are sometimes said to be particularly suitable for so-cal ed “three D” missions, meaning missions
that are “dull, dirty, or dangerous.”4
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.
The Department of the Navy states, for example, that its inventory of 4,094 aircraft at the end of
FY2019 included 99 UAVs, that its projected inventory of 3,912 aircraft at the end of FY2020
wil include 45 UVs, and that its projected inventory of 4,075 aircraft at the end of FY2021 wil
include 57 UVs.5 Even so, some observers have occasional y 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., overal
strategy) document for developing and acquiring Navy and Marine UVs of various types and
integrating them into U.S. naval operations.6
Navy USV and UUV Categories
As shown in Figure 1 and Figure 2, the Navy organizes its USV acquisition programs into four
size-based categories that the Navy cal s large, medium, smal , and very smal , and its UUV
acquisition programs similarly into four size-based categories that the Navy cal s extra-large,
large, medium, and smal . The large UVs discussed in this CRS report fal into the top two USV
categories in Figure 1 and the top UUV category in Figure 2.
The smal er UVs shown in the other categories of Figure 1 and Figure 2, which are not covered
in this report, 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.

4 See, for example, Ann Diab, “ Drones Perform the Dull, Dirty, or Dangerous Work,” T ech.co, November 12, 2014;
Bonnie Robinson, “ Dull, Dirty, Dangerous Mission? Send in the Robot Vehicle,” U.S. Army, August 20, 2015;
Bernard Marr, “ T he 4 Ds Of Robotization: Dull, Dirty, Dangerous And Dear,” Forbes, October 16, 2017.
5 Department of the Navy, Highlights of the Department of the Navy FY 2021 Budget, Figure 3.7 on page 3-7.
6 Department of the Navy, Department of the Navy Unmanned Campaign Framework, March 16, 2021, 37 pp. See also
Megan Eckstein, “ Navy, Marines Unveil How T hey Will Buy and Operate Future Pilotless Aircraft and Crewless
Ships,” USNI News, March 16, 2021; Gina Harkins, “ Why You Should T rust Drone Ships and Unmanned T ech,
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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Figure 1. Navy USV Systems Vision

Source: Slide 3 of briefing by Captain Pete Smal , Program Manager, Unmanned Maritime Systems (PMS 406),
entitled “Unmanned Maritime Systems Update,” January 15, 2019, accessed May 22, 2019, at
https://www.navsea.navy.mil/Portals/103/Documents/Exhibits/SNA2019/UnmannedMaritimeSys-Smal .pdf?ver=
2019-01-15-165105-297.
Figure 2. Navy UUV Systems Vision

Source: Slide 2 of briefing by Captain Pete Smal , Program Manager, Unmanned Maritime Systems (PMS 406),
entitled “Unmanned Maritime Systems Update,” January 15, 2019, accessed May 22, 2019, at
https://www.navsea.navy.mil/Portals/103/Documents/Exhibits/SNA2019/UnmannedMaritimeSys-Smal .pdf?ver=
2019-01-15-165105-297.
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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, some observers have
a raised a question as to whether the large UVs covered in this report should be included in the
top-level count of the number of ships in the Navy. Department of Defense (DOD) officials since
late 2019 have sent mixed signals on this question, but most recently have indicated that a new
Navy force-level goal that wil replace the Navy’s current 355-ship force-level goal (see next
section) wil include large unmanned vehicles (UVs).7
Part of More Distributed Navy Fleet Architecture
The Navy and DOD since 2019 have been working to develop a new Navy force-level goal to
replace the Navy’s current 355-ship force-level goal. This new Navy force-level goal is expected
to introduce a change in fleet architecture, meaning basic the types of ships that make up the
Navy and how these ships are used in combination with one another to perform Navy missions.
This new fleet architecture is expected to be more distributed than the fleet architecture reflected
in the 355-ship goal or previous Navy force-level goals. In particular, the new fleet architecture is
expected to feature
 a smal er proportion of larger ships (such as large-deck aircraft carriers, cruisers,
destroyers, large amphibious ships, and large resupply ships);
 a larger proportion of smal er ships (such as frigates, corvettes, smal er
amphibious ships, smal er resupply ships, and perhaps smal er aircraft carriers);
and
 a new third tier of surface vessels about as large as corvettes or large patrol craft
that wil be either lightly manned, optional y manned, or unmanned, as wel as
large unmanned underwater vehicles (UUVs).
Navy and DOD leaders believe that shifting to a more distributed fleet architecture is

7 In December 2019, it was reported that the Office of Management and Budget (OMB) had directed the Navy to
include in its FY2021 budget submission a legislative proposal to formally change the definition of which ships count
toward the quoted size of the Navy (known as the number of battle force ships) to include not only manned ships, but
also large UVs that operate essentially as unmanned ships. (See Justin Katz, “ OMB: Pentagon Must Submit Proposal to
‘Redefine’ Battleforce Ships to Include Unmanned Vehicles,” Inside Defense, December 20, 2019; Joseph T revithick,
“White House Asks Navy T o Include New Unmanned Vessels In Its Ambitious 355 Ship Fleet Plan,” The Drive,
December 20, 2019; Paul McCleary, “ Navy T o Slash 24 Ships in 2021 Plan, Bolster Unmanned Effort,” Breaking
Defense
, December 20, 2019, David B. Larter, “ Pentagon Proposes Big Cuts to US Navy Destroyer Construction,
Retiring 13 Cruisers,” Defense News, December 24, 2019.)
In January 2020, Admiral Michael Gilday, the Chief of Naval Operations, stated that the top-level expression of the
ship force-level goal resulting from the Navy’s next FSA would not include UVs. (See, for example, Sam LaGrone,
“CNO Gilday Calls for Budget Increase t o Reach 355 Ship Fleet; New Battle Force Count Won’t Include Unmanned
Ships,” USNI News, January 14, 2020; Rich Abott, “CNO: Ship Count Will Not Include Unmanned; Bigger T opline
Needed For Fleet Goal,” Defense Daily, January 15, 2020; John M. Doyle, “CNO W ants Larger Slice of Defense
Budget to Modernize, Meet China T hreat,” Seapower, January 15, 2020; Rich Abott, “CNO: Ship Count Will Not
Include Unmanned; Bigger T opline Needed For Fleet Goal,” Defense Daily, January 15, 2020.)
In September 2020, Secretary of Defense Mark Esper signaled that the stated ship-force level goal will include large
UVs. (See, for example, Megan Eckstein, “ Esper: Unmanned Vessels Will Allow the Navy to Reach 355 -Ship Fleet ,”
USNI News, September 18, 2020.)
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operationally necessary, to respond effectively to the improving maritime anti-
access/area-denial (A2/AD) capabilities of other countries, particularly China;8
technically feasible as a result of advances in technologies for UVs and for
networking widely distributed maritime forces that include significant numbers
of UVs; and
affordable—no more expensive, and possibly less expensive, than the current
fleet architecture, so as to fit within expected future Navy budgets.
Shifting to a more distributed force architecture, Navy and Marine Corps officials have
suggested, wil support the implementation of the Navy and Marine Corps’ new overarching
operational concept, cal ed Distributed Maritime Operations (DMO), and a supporting Marine
Corps operational concept cal ed Expeditionary Advanced Base Operations (EABO). While Navy
officials have provided few details in public about DMO,9 the Navy does state in its FY2021
budget submission that
MUSV and LUSV are key enablers 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. Fielding of MUSV and LUSV will provide the Navy
increased capability and necessary capacity at lower procurement and sustainment costs,
reduced risk to sailors and increased readiness by offloading missions from manned
combatants.10

8 See, for example, David B. Larter, “With China Gunning for Aircraft Carriers, US Navy Says It Must Change How It
Fights,” Defense News, December 6, 2019; Arthur H. Barber, “Redesign the Fleet,” U.S. Naval Institute Proceedings,
January 2019. Some observers have long urged the Navy to shift to a more distributed fleet architecture, on the grounds
that the Navy’s current architecture—which concentrates much of the fleet’s capability into a relatively limited number
of individually larger and more expensive surface ships—is increasingly vulnerable to attack by the improving A2/AD
capabilities (particularly anti-ship missiles and their supporting detection and targeting systems) of potential
adversaries, particularly China. Shifting to a more distributed architecture, these observers have argued, would

complicate an adversary’s targeting challenge by presenting the adversary with a larger number of Navy units
to detect, identify, and track;

reduce the loss in aggregate Navy capability that would result from the destruction of an individual Navy
platform;

give U.S. leaders the option of deploying USVs and UUVs in wartime to sea locations that would be
tactically advantageous but too risky for manned ships; and

increase the modularity and reconfigurability of the fleet for adapt ing to changing mission needs.
For more on China’s maritime A2/AD capabilities, see CRS Report RL33153, China Naval Modernization:
Im plications for U.S. Navy Capabilities—Background and Issues for Congress
, by Ronald O'Rourke.
9 T hen-Chief of Naval Operations Admiral John Richardson, in explaining DMO, stated in December 2018 that “Our
fundamental force element right now in many instances is the [individual] carrier strike group. We’re going to scale up
so our fundamental force element for fighting is at the fleet[ -wide] level, and the [individual] strike groups plug into
those [larger] numbered fleets. And they will be, the strike groups and the fleet together, will be operating in a
distributed maritime operations way.” (Chief of Naval Operations Admiral John Richardson, as quoted in Megan
Eckstein, “ Navy Planning for Gray-Zone Conflict; Finalizing Distributed Maritime Operations for High-End Fight,”
USNI News, December 19, 2018.)
10 Department of Defense Fiscal Year (FY) 2021 Budget Estimates, Navy Justification Book Volume 2 of 5, Research,
Development, T est & Evaluation, February 2020, PDF page 90 of 1,538. T he statement also appears on PDF page 324
of 1,538. For more on the more distributed force architecture, DMO, and EABO, see CRS Report RL32665, Navy
Force Structure and Shipbuilding Plans: Background and Issues for Congress
, by Ronald O'Rourke. See also Kevin
Eyer and Steve McJessy, “ Operationalizing Distributed Maritime Operations,” Center for International Maritime
Security (CIMSEC), March 5, 2019; Christopher H. Popa et al., Distributed Maritim e Operations and Unm anned
System s Tactical Em ploym ent
, Naval Postgraduate School, June 2018, 171 pp. (Sy stems Engineering Capstone Report);
Lyla Englehorn, Distributed Maritim e Operations (DMO) Warfare Innovation Continuum (WIC) Workshop Septem ber
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On December 9, 2020, the outgoing Trump Administration released a document that can be
viewed as its own vision for future Navy force structure and/or a draft version of the FY2022 30-
year Navy shipbuilding plan. The document presents an envisioned Navy force-level goal for
achieving by 2045 a Navy with a more distributed fleet architecture, including 382 to 446 manned
ships, 119 to 166 LUSVs and MUSVs, and 24 to 76 XLUUVs. In establishing its force-level
goals and shipbuilding plans for the Navy, the Biden Administration can choose to adopt, revise,
or set aside this document.11
Accelerated Acquisition Strategies and Enabling Technologies
The Navy wants to employ accelerated acquisition strategies for procuring large UVs, so as to get
them into service more quickly. The Navy’s desire to employ these accelerated acquisition
strategies can be viewed as an expression of the urgency that the Navy attaches to fielding large
UVs for meeting future military chal enges from countries such as China.12
The LUSV and MUSV programs are building on USV development work done by the Strategic
Capabilities Office (SCO) within the Office of the Secretary of Defense (OSD). SCO’s effort to
develop USVs is cal ed Ghost Fleet, and its LUSV development effort within Ghost Fleet is
cal ed Overlord.
As shown in Figure 3, the Navy has identified five key enabling groups of technologies for its
USV and UUV programs.13 Given limitations on underwater communications (most radio-
frequency electromagnetic waves do not travel far underwater), technologies for autonomous
operations (such as artificial intel igence) wil be particularly important for the XLUUV program
(and other UUV programs).14
In May 2019, the Navy established a surface development squadron to help develop operational
concepts for LUSVs and MUSVs. The squadron wil initial y consist of a Zumwalt (DDG-1000)
class destroyer and one Sea Hunter prototype medium displacement USV (Figure 4). A second
Sea Hunter prototype wil reportedly be added around the end of FY2020, and LUSVs and
MUSVs wil then be added as they become available.15

2017 After Action Report, Naval Postgraduate School, December 2017, 99 pp.
11 For more on the December 9, 2020, document, see CRS Report RL32665, Navy Force Structure and Shipbuilding
Plans: Background and Issues for Congress
, by Ronald O'Rourke.
12 A number of other DOD acquisition programs are also employing rapid or accelerated acquisition strategies of one
kind or another, in some cases using special acquisition authorities that Congress has granted to DOD. For additional
discussion, see CRS Report R45068, Acquisition Reform in the FY2016-FY2018 National Defense Authorization Acts
(NDAAs)
, by Moshe Schwartz and Heidi M. Peters.
13 For additional discussion of some of the enabling technologies shown in Figure 3, see Pete Small, “Empowering the
Unmanned Maritime Revolution,” Undersea Warfare, Spring 2019: 12 -13.
14 For more on the use of artificial intelligence in defense programs, see CRS Report R45178, Artificial Intelligence
and National Security
, by Kelley M. Sayler.
15 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 3. Enabling Technologies for USVs and UUVs

Source: Slide 4 of briefing by Captain Pete Smal , Program Manager, Unmanned Maritime Systems (PMS 406),
entitled “Unmanned Maritime Systems Update,” January 15, 2019, accessed May 22, 2019, at
https://www.navsea.navy.mil/Portals/103/Documents/Exhibits/SNA2019/UnmannedMaritimeSys-Smal .pdf?ver=
2019-01-15-165105-297.
Figure 4. 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.
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LUSV, MUSV, and LXUUV Programs in Brief
Navy Vision and Schedule for USVs and UUVs
Figure 5 and Figure 6 show the Navy’s vision and schedule for building, testing, and conducting
fleet experiments with USVs and UUVs, including the LUSV, the MUSV, and the XLUUV, along
with supporting efforts such as the Overlord and Sea Hunter prototype USVs, as wel as smal er
USVs and UUVs that are not covered in this report. In the two figures, the numbers inside the
smal green triangles represent quantities of the systems in question, a downward-pointing green
triangle indicates the start of construction, and an upward-pointing triangle indicates the
completion of construction. For example, Figure 5 shows that under the Navy’s USV vision, a
single MUSV would start construction in 2020 and complete construction near the end of 2022,
and that the next MUSV would start construction in 2023 and complete construction in 2025.
Figure 5. Navy USV Systems Vision

Source: Captain Pete Smal , “PMS 406 Unmanned Maritime Systems,” briefing at NDIA Undersea Warfare
Conference, March 24, 2021, slide 3.
Notes: GFE means government-furnished equipment, meaning equipment that the government wil provide to
the firm that is building the USV, for incorporation into the USV.
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Figure 6. Navy UUV Systems Vision

Source: Captain Pete Smal , “PMS 406 Unmanned Maritime Systems,” briefing at NDIA Undersea Warfare
Conference, March 24, 2021, slide 4.
Notes: DDS is dry deck shelter, which is a module that can be attached to the top surface of a submarine for
the purpose of carrying a special payload. PHS is payload handling system. IPOE is intel igence preparation of the
operational environment. MCM is mine countermeasures. TTL&R is torpedo tube launch and recovery. INC is
increment (i.e., version). DIU is Defense Innovation Unit, which is a DOD organization. NSW is naval special
warfare.
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. Figure
7
shows a detail from a Navy briefing slide showing images of prototype LUSVs and silhouettes
of a notional LUSV and a notional MUSV. Figure 8 and Figure 9 show ships that have been used
as LUSV prototypes. In unclassified presentations on the program, the Navy has used images of
offshore support ships used by the oil and gas industry to il ustrate the kinds of ships that might
be used as the basis for LUSVs.16


16 Sam LaGrone, “Navy Wants 10-Ship Unmanned ‘Ghost Fleet’ to Supplement Manned Force,” USNI News, March
13, 2019.
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Figure 7. Prototype and Notional LUSVs and MUSVs

Source: Detail from Navy briefing slide entitled Unmanned Maritime Systems, slide 5 in a Navy briefing entitled
“Designing & Building the Surface Fleet: Unmanned and Smal Combatants,” by Rear Admiral Casey Moton at a
June 20, 2019, conference of the American Society of Naval Engineers (ASNE).
Figure 8. LUSV Prototype

Source: Cropped version of photograph accompanying Mal ory 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 9. LUSV prototype

Source: Cropped version of photograph accompanying Mal ory 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.
The Navy wants LUSVs to be low-cost, high-endurance, reconfigurable ships based on
commercial ship designs, with ample capacity for carrying various modular payloads—
particularly anti-surface warfare (ASuW) and strike payloads, meaning principal y anti-ship and
land-attack missiles.17
The Navy wants LUSVs to be capable of operating with human operators in the loop,18 or semi-
autonomously (with human operators on the loop),19 or fully autonomously, and to be capable of
operating either independently or in conjunction with manned surface combatants. Although
referred to as UVs, LUSVs might be more accurately described as optional y 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.20
LUSVs are to feature both built-in capabilities and an ability to accept modular payloads, and are
to use existing Navy sensors and weapon launchers. The Navy states:
Building upon the Department of Defense’s Strategic Capabilities Office (SCO) funded
and Navy executed experimentation with USVs in Project Overlord, the Navy’s LUSV will
be a high-endurance vessel based on commercial specifications, capable of weeks -long
deployments and trans-oceanic transits. With a large payload capacity, the LUSV will be
designed to conduct a variety of warfare operations initially in conjunction with manned

17 T he Navy states that the LUSV “provides distributed fires” and will include an “offensive missile capability.” See
slide 5 of briefing by Captain Pete Small, Program Manager, Unmanned Maritime Systems (PMS 406), entitled
“Unmanned Maritime Systems Update,” January 15, 2019, accessed May 22, 2019, at https://www.navsea.navy.mil/
Portals/103/Documents/Exhibits/SNA2019/UnmannedMaritimeSys-Small.pdf?ver=2019-01-15-165105-297.
18 T he Navy states that having the operator in the loop can be understood as referring to continuous or near-continuous
observation and/or control of the UV by the operator. (Source: Navy email to CRS dated June 4, 2019.)
19 T he Navy states that having the operator on the loop can be understood as referring to a UV that is operating semi -
autonomously, with the UV controlling its own actions much of the time, but with a human operator potentially
intervening from time to time in response to either a prompt from the UV or data sent from the UV or other sources.
(Source: Navy email to CRS dated June 4, 2019.)
20 See, for example, David B. Larter, “US Navy Looks to Ease into Using Unmanned Robot Ships with a Manned
Crew,” Defense News, January 29, 2019.
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surface combatants while under the positive control of a man-in-the-loop for employment
of weapons systems.
The Navy is taking an iterative, systems engineering approach to obtaining this technology
and has designed an integration and experimentation plan that will validate high reliability
mechanical and electrical systems, autonomous navigation and maneuvering, integration
of combat system, and platform command and control capabilities prior to employment
opportunities.
LUSV Design Studies contracts were awarded in September 2020 to six Industry teams 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
follow on development contract. Both Industry and the Navy are using these collaborative
interactions to significantly advance the knowledge base that will feed into the LUSV
program.21
FY2020 Legislative Activity
In marking up the Navy’s proposed FY2020 budget, some of the congressional defense
committees expressed concerns over whether the Navy’s accelerated acquisition strategies
provided enough time to adequately develop concepts of operations and key technologies for
large UVs, particularly the LUSV. In its report (S.Rept. 116-48 of June 11, 2019) on the FY2020
National Defense Authorization Act (S. 1790), the Senate Armed Services Committee stated
The committee is concerned that the budget request’s concurrent approach to LUSV
design, technology development, and integration as well as a limited understandin g of the
LUSV concept of employment, requirements, and reliability for envisioned missions pose
excessive acquisition risk for additional LUSV procurement in fiscal year 2020. The
committee is also concerned by the unclear policy implications of LUSVs, including ill-
defined international unmanned surface vessel standards and the legal status of armed or
potentially armed LUSVs.
Additionally, the committee notes that the Navy’s “Report to Congress on the Annual
Long-Range Plan for Construction of Naval Vessels for Fiscal Year 2020” acknowledges
similar issues: “Unmanned and optionally-manned systems are not accounted for in the
overall battle force[.] ... The physical challenges of extended operations at sea across the
spectrum of competition and conflict, the concepts of operations for these platforms, and
the policy challenges associated with employing deadly force from autonomous vehicles
must be well understood prior to replacing accountable battle force ships.”
The committee believes that further procurement of LUSVs should occur only after the
lessons learned from the current SCO initiative have been incorporated into the next
solicitation to enable incremental risk reduction.
In addition, the committee believes that the LUSV program, which appears likely to exceed
the Major Defense Acquisition Program cost threshold, would benefit from a more rigorous
requirements definition process, analysis of alternatives, and deliberate acquisition
strategy.22
S.Rept. 116-48 also stated

21 Statement of Fredrick J. Stefany, Acting Assistant Secretary of the Navy for Research, Develop ment 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 Unm anned Systems, March 18, 2021, p. 14.
22 S.Rept. 116-48, p. 80.
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While recognizing the need for prototypes to reduce acquisition risk, the committee is
concerned that the acquisition strategies for the Large USV, Medium USV, Orca UUV,
and Snakehead UUV could lead to procurement of an excessive number of systems before
the Navy is able to determine if the USVs and UUVs meet operational needs.
Therefore, the committee directs the Secretary of the Navy to submit a rep ort to the
congressional defense committees, not later than November 1, 2019, that provides
acquisition roadmaps for the Large USV, Medium USV, Orca UUV, and Snakehead
UUV.23
In its report (S.Rept. 116-103 of September 12, 2019) on the FY2020 DOD Appropriations Act
(S. 2474), the Senate Appropriations Committee stated that
the Committee is concerned that for several unmanned programs the Navy is pursuing
acquisition strategies that would limit future competitive opportunities by awarding
system-level prototypes early in the acquisition process and failing to articulate capability,
requirements or technology roadmaps to encourage industrial innovation. The Assistant
Secretary of the Navy (Research, Development and Acquisition) is directed to submit to
the congressional defense committees with the fiscal year 2021 President’s budget request
such acquisition roadmaps for each unmanned acquisition program that include no less
than mission requirements, program requirements for each increment, key technologies,
acquisition strategies, test strategies, sub-system and system-level prototyping plans, and
cost estimates.24
S.Rept. 116-103 also stated
The Committee fully supports additional investments in unmanned and autonomous
technologies, systems and sub-systems, including surface and sub-surface vessels.
However, the Committee is concerned with the proposed acquisition and funding strategies
for the MUSV and LUSV in this budget request, to include the Future Years Defense
Program. Therefore, the Committee recommends several adjustme nts, as detailed
elsewhere in this report, and directs the Assistant Secretary of the Navy (Research,
Development and Acquisition) to review the acquisition strategies for these programs to
address congressional concerns, as appropriately balanced with warfighter needs. (Page
194)25

23 S.Rept. 116-48, p. 106. T he report stated further on pages 106-107 that
Each roadmap shall: (1) Identify the applicable requirements document (e.g., T op Level
Requirements); (2) Describe the threshold and objective values for each characteristic, key
performance parameter (KPP), or other measure in the applicable requirements document; (3)
Identify increments of vessels in each program; (4) For each such increment, identify specific
entrance and exit criteria that build toward the specified requirements (e.g., characteristic, KPP, or
other measure), including demonstrated hardware and software functionality; (5) Identify the
quantity of vessels needed in each increment to perform the required testing or meet operational
needs; (6) Describe the concept of operations for each increment; (7) Identify the key pieces of
hardware and software needed for each increment, including communications security material,
off-board line-of-sight and satellite communications, and military datalinks; (8) Describe the extent
to which each increment of vessels will be equipped with weapons, enumerate such weapons, and
describe the associated target detect -to-engage sequence of events for each such weapon; (9)
Provide the subsystem-level prototyping plan for each increment, including for each such effort the
planned cost, schedule, and performance; and (10) Provide the acquisition plan for each increment,
including the planned cost, schedule, and performance.
24 S.Rept. 116-103, p. 191.
25 S.Rept. 116-103, p. 194.
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The explanatory statement for the final version of the FY2020 DOD Appropriations Act (Division
A of H.R. 1158/P.L. 116-93 of December 20, 2020) stated
The Secretary of the Navy is directed to comply with the full funding policy for LUSVs in
future budget submissions. Further, the agreement recommends $50,000,000 for the design
of future LUSVs without a vertical launch system [VLS] capability in fiscal year 2020.
Incremental upgrade capability for a vertical launch system may be addressed in future
fiscal years. It is directed that no funds may be awarded for the conceptual design of future
LUSVs until the Assistant Secretary of the Navy (Research, Development and Acquisition)
briefs the congressional defense committees on the updated acquisition strategy for
unmanned surface vessels.26
FY2021 Budget Submission
In response to the markups from the congressional defense committees, the Navy’s FY2021
budget submission proposed modifying the acquisition strategy for the LUSV program so as to
provide more time for developing operational concepts and key technologies before entering into
serial production of deployable units. Under the Navy’s proposed modified LUSV acquisition
strategy, the Navy proposed using research and development funding to acquire two additional
prototypes in FY2021 and one more additional prototype in FY2022 before shifting in FY2023 to
the use of procurement funding for the procurement of deployable LUSVs at annual procurement
rates in FY2023-FY2025 of 2-2-3. The Navy’s FY2021 budget submission states
Major changes [in the LUSV program] from [the] FY 2020 President’s Budget request to
[the] FY 2021 President’s Budget request [include the following]:
(1) The program will award Conceptual Design (CD) contracts to multiple vendors in
FY20. The CD effort will support refinement of a LUSV Performance Specification that
does not include the Vertical Launch System (VLS). The final Performance Specification
will define a LUSV with reservations in the design to support integration of a variety of
capabilities and payloads. This effort, which was originally planned to award in Q2 [the
second quarter of] FY 2020 will be delayed until early Q4 [the fourth quarter of] FY 2020
in order to support amendment of the CD Request for Proposals (RFP), Performance
Specification, and associated artifacts.
(2) The delay in award of the LUSV CD effort will delay follow-on activities (RFP
[Request for Proposals], [and] source selection) leading up to the award of the LUSV Detail
Design and Construction (DD&C) contract. DD&C award will be delayed one year, from
FY 2021 to FY 2022. The DD&C award will deliver a non-VLS LUSV prototype based
on the Performance Specification developed during the CD effort.
(3) In lieu of the FY 2020 President’s Budget request plan of awarding the LUSV DD&C
contract in FY21, the Navy is planning to procure up to two additional Overlord prototypes,
building on the lessons learned through the Ghost Fleet program and advances in C4I and
combat system prototyping efforts.
(4) The Navy plans to transition LUSV to a program of record in FY 2023 and align [the
program’s] procurement funding to the Shipbuilding and Conversion, Navy (SCN)
account.27

26 Explanatory statement for Division A of H.R. 1158, PDF page 274 of 414.
27 See also Justin Katz, “Navy Says It Will Adjust to LUSV Restrictions; New Plan Will Be Part of Next Budget,”
Inside Defense, January 16, 2020; Vivienne Machi, “ FY ’21 Budget Request to Include ‘Adjustment’ to LUSV
Procurement Schedule, PEO Says,” Defense Daily, January 16, 2020.
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A January 13, 2020, press report stated that the Navy planned to submit a report on the Navy’s
concepts of operations for LUSVs and MUSVs in April 2020.28
September 4, 2020 Contract Award
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 Ingal s Inc. is $7,000,000;

the contract awarded to Lockheed Martin Corp. is $6,999,978;

the contract awarded to Bol inger 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.
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 Oppo rtunities (now
beta.SAM.gov) with eight offers received. The Naval Sea Systems Command,
Washington, D.C., is the contracting activity.29
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.

28 Mallory Shelbourne, “Navy to Submit Report in April on Unmanned CONOPS Development,” Inside Defense,
January 13, 2020. See also David B. Larter, “Fleet Commander Directs US Navy’s Surface Force to Develop Conce pts
for Unmanned Ships,” Defense News, January 2, 2020; David B. Larter, “ Unclear on Unmanned: T he US Navy’s Plans
for Robot Ships Are on the Rocks,” Defense News, January 10, 2021; David B. Larter, “ Unclear on Unmanned, Part 2:
On Capitol Hill, the US Navy Has a Credibility Problem,” Defense News, January 11, 2021; David B. Larter, “ Unclear
on Unmanned, Part 3: A New Year’s Resolution to Slow Down,” Defense News, January 11, 2021.
29 Department of Defense, “ Contracts For Sept. 4, 2020,” accessed September 8, 2020. T he 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.
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“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.30
MUSV Program
The Navy defines MUSVs as being 45 feet to 190 feet long, with displacements of roughly 500
tons. 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 intel igence,
surveil ance 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.31 The first MUSV prototype was funded in FY2019 and the
Navy wants fund the second prototype in FY2023.
The MUSV program is building on development work by the Defense Advanced Research
Projects Agency (DARPA) under its Anti-Submarine Warfare Continuous Trail Unmanned Vessel
(ACTUV) effort and the Office of Naval Research (ONR) under its Medium Displacement USV
effort. As shown in Figure 1, this work led to the design, construction, and testing of the
prototype Sea Hunter medium displacement USV, which has a reported length of 132 feet (about
40.2 meters) and a displacement of about 140 tons.32 The Navy’s MUSV program is also to
employ a fleet-ready command and control (C2) solution for USVs that was developed by the
Strategic Capabilities Office for the LUSV program. The Navy states that
MUSV is an unmanned sensor-ship, built to carry modular payloads, and standardized for
easy integration with current Navy systems. Inexpensive compared to manned combatants,
they can be built in numbers, quickly adding capacity to the Fleet. MUSV delivers a
distributed sensor network that can navigate and operate with man in/on the loop oversight,
and will be capable of weeks -long deployments and trans -oceanic transits. The Navy
awarded a design and fabrication contract to L3Harris to develop the first MUSV prototype
in accordance with Interim Top Level Requirements approved in 2019. The MUSV
prototype is targeted for delivery in FY 2023.33

30 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.
31 T his is a reference to Section 804 of the FY2016 National Defense Authorization Act ( S. 1356/P.L. 114-92 of
November 25, 2015). T he rapid prototyping authority provided by that section is now codified at 10 U.S.C. 2302 note.
For more on this authority, see “ Middle T ier Acquisition (Section 804),” MIT RE, undated, accessed May 24, 2019, at
https://aida.mitre.org/middle-tier/; and “ Acquisition Process, Middle T ier Acquisition (Section 804),” AcqNotes,
updated March 26, 2019, accessed May 24, 2019, at http://acqnotes.com/acqnote/acquisitions/middle-tier-acquisitions.
32 See, for example, Megan Eckstein, “ Sea Hunter Unmanned Ship Continues Autonomy T esting as NAVSEA Moves
Forward with Draft RFP ,” USNI News, April 29, 2019; Evan Milberg, “ DARPA “ Sea Hunter,” World’s Largest
Autonomous Ship, T ransferred to U.S. Navy ,” Com posites Manufacturing Magazine, February 12, 2018; Sydney J.
Freedberg Jr., “ DSD [Deputy Secretary of Defense] Work Embraces DARPA’s Robot Boat, Sea Hunter,” Breaking
Defense
, April 7, 2016.
33 Statement of Fredrick J. Stefany, Acting Assistant Secretary of the Navy for Research, Develop ment and Acquisition
(ASN [RD&A]) and Vice Admiral James W. Kilby, Deputy Ch ief of Naval Operations for Warfare Systems and
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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 al options exercised, the contract is valued at $281,435,446 if additional funding
is provided in future budget years.”34 The Navy reportedly stated that there were five competitors
for the contract, but did not identify the other four.35 Figure 10 shows a rendering of L3Harris’s
design concept.
Figure 10. 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.
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
MUSV will provide intelligence, surveillance and reconnaissance to t he 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.
L3Harris is a world leader in actively powered Unmanned Surface Vehicle (USV) systems,
with over 115 USVs delivered worldwide. L3Harris’ USVs are actively serving the Navy,
universities, research institutions and commercial businesses.36

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. 15.
34 PEO Unmanned and Small Combatants Public Affairs, “ Navy Awards Contract for Medium Unmanned Surface
Vehicle Prototype,” Naval Sea Systems Command, July 13, 2020.
35 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.
36 L3Harris T echnologies, “L3Harris T echnologies Awarded Medium Unmanned Surface Vehicle Program from US
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XLUUV Program
The XLUUV program, also known as the Orca program, was established to address a Joint
Emergent Operational Need (JEON). As shown in Figure 2, 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.37 Consequently, XLUUVs instead wil transported to a forward
operating port and then launched from pier. The Department of the Navy’s March 16, 2021,
unmanned campaign framework document states that the XLUUV wil be designed “to
accommodate a variety of large payloads….”38 The Navy testified on March 18, 2021, that mines
wil be the initial payload for XLUUVs.39
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.40 (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.41 Boeing has partnered with the Technical Solutions division
of Huntington Ingal s Industries (HII) to build Orca XLUUVs.42 (A separate division of HII—
Newport News Shipbuilding (NNS) of Newport News, VA—is one of the Navy’s two submarine
builders.)
The Navy wants procure additional XLUUVs at a rate of two per year starting in FY2023. The
Navy’s FY2021 budget submission does not include funding for the procurement of additional
XLUUVs in FY2021 or FY2022. The Navy is proposing to fund the procurement of XLUUVs in
FY2023 and subsequent years through the Other Procurement, Navy (OPN) appropriation
account.
In June 2020, it was reported that a study of future Navy force-level requirements led by the Cost
Assessment and Program Evaluation (CAPE) office within the Office of the Secretary of Defense
(OSD) recommended a future Navy with, among other things, up to 50 XLUUVs.43
Boeing’s Orca XLUUV design wil be informed by (but wil differ in certain respects from) the
design of Boeing’s Echo Voyager UUV (Figure 11, Figure 12, and Figure 13).44 Echo Voyager 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

Navy,” August 18, 2020.
37 Navy submarines equipped with large-diameter vertical launch tubes can launch missiles or other payloads with
diameters of up to about 83 inches.
38 Department of the Navy, Department of the Navy Unmanned Campaign Framework, March 16, 2021, p. 16.
39 Richard R. Burgess, “ Navy’s Orca XLUUV to Have Mine-Laying Mission, Adm. Kilby Says,” Seapower, March 18,
2021.
40 Department of Defense, Contracts for Feb. 13, 2019.
41 Department of Defense, Contracts for March 27, 2019.
42 See, for example, Hugh Lessig, “Shipbuilder Lends a Hand with Rise of Robot Submarines,” Defense News, May 26,
2019.
43 David B. Larter, “ T o Compete with China, An Internal Pentagon Study Looks to Pour Money into Robot
Submarines,” Defense News, June 1, 2020.
44 See, for example, Hugh Lessig, “Shipbuilder Lends a Hand with Rise of Robot Submarines,” Defense News, May 26,
2019.
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about 900 cubic feet. Echo Voyager can also accommodate external payloads.45 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
reconfigurable, modular payload bay to support multiple payloads and a variety of
missions.46
Figure 11. Boeing Echo Voyager UUV

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

45 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.
46 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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Figure 12. Boeing Echo Voyager UUV

Source: Boeing photograph posted at https://www.boeing.com/defense/autonomous-systems/echo-voyager/
index.page#/gal ery.
Figure 13. 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.
FY2021-FY2025 Funding
Table 1 shows FY2021-FY2025 requested and programmed funding for the large UV programs
covered in this report.
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Table 1. FY2021-FY2025 Requested and Programmed Funding for Large UVs
Mil ions of dol ars, rounded to nearest tenth
FY21-
FY25
Program
FY21
FY22
FY23
FY24
FY25
total
LUSV research and development funding
238.6
377.2
144.5
198.7
134.9
1,093.9
(Quantity—prototype LUSVs)
(2)
(1)
(0)
(0)
(0)
(3)
LUSV (procurement funding
0
0
455.0
373.6
536.6
1,365.2
(Quantity—deployable LUSVs)
(0)
(0)
(2)
(2)
(3)
(7)
MUSV research and development funding
26.3
30.0
43.0
43.9
44.7
187.9
(Quantity—prototype MUSVs)
(0)
(0)
(1)
(0)
(0)
(1)
LUSV and MUSV enabling technologies
199.1
122.8
192.8
77.9
80.9
673.9
research and development funding
XLUUV research and development funding
115.9
43.0
78.5
77.0
7.7
322.1
(Quantity)
(0)
(0)
(0)
(0)
(0)
(0)
XLUUV procurement funding
0
0
158.5
162.6
232.8
552.9
(Quantity)
(0)
(0)
(2)
(2)
(2)
(6)
Source: Navy FY2021 budget submission. LUSV is Project 3066 within PE (Program Element) 0603178N (line 27
in the Navy’s FY2021 research and development account). MUSV is Project 3428 within PE 0603178N (line 27).
LUSV and MUSV enabling technologies is Project 3067 within PE 0603178N (line 27). XLUUV is Project 3394
within PE 0604536N (line 89).
Note: Totals may not add due to rounding.
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 More Distributed Fleet Architecture
One potential oversight issue for Congress concerns the analytical basis for the Navy’s desire to
shift to a more distributed fleet architecture featuring a significant contribution from large UVs.
Potential oversight questions for Congress include the following:
 What Navy analyses led to the Navy’s decision to shift toward a more distributed
architecture?
 What did these analyses show regarding the relative costs, capabilities, and risks
of the Navy’s current architecture and the more distributed architecture?
 How wel developed, and how wel tested, are the operational concepts
associated with the more distributed architecture?
Concept of Operations (CONOPS)
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
wil operate these UVs in conjunction with manned Navy ships in various operational scenarios,
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and consequently how, exactly, these UVs wil fit into the Navy’s overal force structure and
operations. 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 using these large UVs in 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 al , that the Navy
wil have to change the performance requirements for these large UVs as a
consequence of more fully developing their 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 wil initial y consist of a
Zumwalt (DDG-1000) class destroyer and one Sea Hunter prototype medium displacement USV
(Figure 4). A second Sea Hunter prototype wil reportedly be added around the end of FY2020,
and LUSVs and MUSVs wil then be added as they become available.47 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
want to have the fleet trained and ready to start using UUVs and USVs when industry is
ready to deliver them.48
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.

47 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.
48 Megan Eckstein, “ USV, UUV Squadrons T esting Out Concepts Ahead of Delivery of T heir Vehicles,” USNI News,
September 9, 2020.
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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.49
Accelerated Acquisition Strategies and Funding Method
Another potential oversight issue for Congress concerns the accelerated acquisition strategies that
the Navy wants to use for these large UV programs. Potential oversight questions for Congress
include the following:
 What are the potential costs, benefits, and risks of pursuing these accelerated
strategies rather than a more traditional acquisition approach that would spend
more time developing the technologies and operational concepts for these UVs
prior to putting them into serial production? How are those considerations
affected by the shift in the international security environment from the post-Cold
War era to the new era of renewed major power competition?50
 Are the Navy’s proposed changes to the LUSV’s accelerated acquisition strategy
appropriate and sufficient?
 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?
Technical, Schedule, and Cost Risk
Another potential oversight issue for Congress concerns the amount of technical, schedule, and
cost risk in these programs, particularly given that these platforms potential y are to operate at sea
unmanned and semi-autonomously or autonomously for extended periods of time. Potential
oversight questions for Congress include the following:
 How much risk of this kind do these programs pose, particularly given the
enabling technologies that need to be developed for them?
 In addition to the Navy’s proposed changes to the LUSV’s acquisition strategy,
what is the Navy doing to mitigate or manage cost, schedule, and technical risks
while it seeks to deploy these UVs on an accelerated acquisition timeline? Are
these risk-mitigation and risk-management efforts appropriate and sufficient?
 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?
A June 1, 2020, press report states
The U.S. military is banking on unmanned surface and subsurface vessels to boost its
capacity in the face of a tsunami of Chinese naval spending. But before it can field the
systems, it must answer some basic questions.

49 Aidan Quigley, “ Navy Finishing Unmanned Surface Vehicles Concept of Operations ‘in Next Few Months,’” Inside
Defense
, October 30, 2020.
50 For more on this shift, see CRS Report R43838, Renewed Great Power Competition: Implications for Defense—
Issues for Congress
, by Ronald O'Rourke.
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How will these systems deploy? How will they be supported overseas? Who will support
them? Can the systems be made sufficiently reliable to operate alone and unafraid on the
open ocean for weeks at a time? Will the systems be able to communicate in denied
environments?
As the Navy goes all-in on its unmanned future, with billions of dollars of investments
planed, how the service answers those questions will be crucial to the success or failure of
its unmanned pivot.51
A June 23, 2020, press report states
The Navy’s transition from prototype to program of record for its portfolio of unmanned
surface and undersea systems is being aided by industry, international partners and
developmental squadrons, even as the program office seeks to ease concerns that the
transition is happening too fast, the program executive officer for unmanned and smal
combatants said today.
Rear Adm. Casey Moton said he’s aware of concerns regarding how unmanned systems –
particularly the Large Unmanned Surface Vessel – will be developed and used by the fleet,
but he’s confident in his team’s path forward.
“From my standpoint we are making a lot of great progress in working out the technical
maturity, answering those kinds of questions (about how to employ and sustain the vessels)
and getting the requirements right before we move into production,” he said in a virtual
event today co-hosted by the U.S. Naval Institute and the Center for Strategic and
International Studies.52
An August 17, 2020, press report states
As the U.S. Navy pushes forward with developing its large unmanned surface vessel,
envisioned as a kind of external missile magazine that will tag along with larger manned
surface combatants, a growing consensus is forming that the service need s to get its
requirements and systems right before making a big investment.…
In an exclusive July 16 interview with Defense News, Chief of Naval Operations Adm.
Michael Gilday said that while the [congressional] marks [on the program] were
frustrating, he agreed with Congress that requirements must be concrete right up front.
“The approach has to be deliberate,” Gilday said. “We have to make sure that the systems
that are on those unmanned systems with respect to the [hull, mechanical and electrical
system], that they are designed to requirement, and perform to requirement. And most
importantly, are those requirements sound?
“I go back to [a question from years ago relating to the development of the Navy’s Littoral
Combat Ship (LCS)]: Do I really need a littoral combat ship to go 40 knots? That’s going
to drive the entire design of the ship, not just the engineering plant but how it’s built. That
becomes a critical factor. If you take your eye off the ball with respect to requirements, you
can find yourself drifting. That has to be deliberate.”
Gilday has called for the Navy to pursue a comprehensive “Unmanned Campaign Plan”
that creates a path forward for developing and fielding unmanned systems in the air, on the
sea and under the water. Right now, the effort exists in a number of different programs that
may not all be pulling in the same direction, he said.

51 David B. Larter, “ US Navy Embraces Robot Ships, But Some Unresolved Issues Are Holding T hem Back,” Defense
News
, June 1, 2020. See also Bryan Clark, “ Pentagon Needs T o Go Faster—And Slower—On Unmanned Systems,”
Forbes, June 11, 2020.
52 Megan Eckstein, “ Program Office Maturing USVs, UUVs With Help From Industry, International Partners,” USNI
News
, June 23, 2020.
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“What I’ve found is that we didn’t necessarily have the rigor that’s required across a
number of programs that would bring those together in a way that’s driven toward
objectives with milestones,” Gilday told Defense News. “If you took a look at [all the
programs], where are there similarities and where are there differences? Where am I
making progress in meeting conditions and meeting milestones that we can leverage in
other experiments?
“At what point do I reach a decision point where I drop a program and double down on a
program that I can accelerate?”53
A September 8, 2020, press report states:
Several Navy program officials and resource sponsors today outlined how they’ll spend
the next couple years giving Congress enough confidence in unmanned surface and
underwater vehicles to allow the service to move from prototyping into programs of record.
Across the entire family of USVs and UUVs, the Navy has pro totypes in the water today
for experimentation and in tandem is making plans to design and buy the next better vehicle
or more advanced payloads, with the idea that the service will iterate its way to achieve
congressional confidence and authorization to move forward on buying these unmanned
systems in bulk.
Rear Adm. Casey Moton, the program executive officer for unmanned and small
combatants, spoke today at the Association for Unmanned Vehicle Systems International
(AUVSI) annual defense conference and provided an update on the status of his portfolio
of UUVs and USVs, some of which have run into trouble with lawmakers not convinced
of their technical maturity and their tactical utility.
Anticipating audience questions, he said in his speech, “what about Congress? What about
the marks and the report language and the questions? So I’m going to put some of that into
context from my perspective. I believe the discussion with Congress has not been about if
unmanned vessels will be part of the Navy. ‘If’ has not been the focus. I don’t even believe
right now that ‘if’ is a major question. The focus has been on ‘how,’ with a healthy dose
of ‘what,’ in terms of requirements and mission type. And of course, ‘how many’ is a
question. How many, I will not focus on today. How many is dependent on Navy and
[Office of the Secretary of Defense] force structure work. But for PEO USC, how many is
ultimately important, but our focus now in this prototyping and experimentation and
development phase is on the how, and working with our requirements sponsors and the
fleet on the what.”
The most ambitious part of the Navy’s current plan calls for the start of a Large USV
program of record in Fiscal Year 2023, despite the LUSV being the piece of the family of
USVs that Congress takes issue with the most. The Navy intends for these ships to be
armed with vertical launch system cells to fire off defensive and offensive missiles—with
sailors onboard manned ships overseeing targeting and firing decisions, since there would
be no personnel on the LUSV.54
Annual Procurement Rates
Another oversight issue for Congress concerns the Navy’s planned annual procurement rates for
the LUSV and XLUUV programs during the period FY2021-FY2025. Potential oversight

53 David B. Larter, “ In Developing Robot Warships, US Navy Wants to Avoid Another Littoral Combat Ship,” Defense
News
, August 17, 2020. See also Loren T hompson, “ U.S. Navy Mounts Campaign T o Convince Congress T hat
Unmanned Vessels Are Critical T o Winning Future Wars,” Forbes, August 17, 2020.
54 Megan Eckstein, “ Navy Pushing to Maintain 2023 USV Program of Record T imeline,” USNI News, September 8,
2020.
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questions for Congress include, What factors did the Navy consider in arriving at them, and in
light of these factors, are these rates too high, too low, or about right?
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 implications would the more distributed architecture have for required
numbers, annual procurement rates, and maintenance workloads for large surface
combatants (i.e., cruisers and destroyers) and smal surface combatants (i.e.,
frigates and Littoral Combat Ships)?
 What portion of these UVs might be built or maintained by facilities other than
shipyards that currently build the Navy’s major combatant ships?55
 To what degree, if any, might the more distributed architecture and 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 glider56 in the sea approximately 100 kilometers off the Philippines in

55 For an opinion piece addressing this issue, see Collin Fox, “ Distributed Manufacturing for Distributed Lethality,”
Center for International Maritime Security (CIMSEC), February 26, 2021.
56 A glider is a type of UUV. T he 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 th e glider, see, for example, Sam LaGrone, “ Updated: Chinese Seize
U.S. Navy Unmanned Vehicle,” USNI News, December 16, 2016.
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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
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 impo undment,
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.57
Personnel Implications
Another oversight issue for Congress concerns the potential personnel implications of
incorporating a significant number of large UVs into the Navy’s fleet architecture. Potential
questions for Congress include the following:
 What implications might these large UVs have for the required skil s, training,
and career paths of Navy personnel?
 Within the Navy, what wil be the relationship between personnel who crew
manned ships and those who operate these large UVs?

57 Evan Karlik, “US-China T ensions—Unmanned Military Craft Raise Risk of War,” Nikkei Asian Review, June 28,
2019. See also David B. Larter, “ T he US Navy Says It’s Doing Its Best to Avoid a ‘T erminator’ 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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Annual Funding
Another oversight issue for Congress concerns the funding amounts for these programs that the
Navy has requested for these programs for FY2021. Potential oversight questions for Congress
include the following:
 Has the Navy accurately priced the work on these programs that it is proposing to
do in FY2021?
 To what degree, if any, has funding been requested ahead of need? To what
degree, if any, is the Navy insufficiently funding elements of the work to be done
in FY2021?
 How might the timelines for these programs be affected by a decision to reduce
(or add to) the Navy’s requested amounts for these programs?
Legislative Activity for FY2022
The Navy’s proposed FY2022 budget wil be submitted to Congress later this year.
Legislative Activity for FY2021
Summary of Congressional Action on FY2021 Funding Request
Table 2
summarizes congressional action on the Navy’s FY2021 funding request for the LUSV,
MUSV, and XLUUV programs and their enabling technologies.
Table 2. Congressional Action on FY2021 Large UV Funding Request
Mil ions of dol ars, rounded to the nearest tenth


Authorization
Appropriation

Request
HASC
SASC
Conf.
HAC
SAC
Conf.
Navy research and development account
MUSVs and LUSVs (Line 27, Projects 3066, 3067, 3428)
464.0
270.4
0
259.2
259.2
91.2
93.7
MUSVs (Line 27A)
0
0
0
0
0
55.4
55.4
XLUUV (Line 89, Project 3394)
115.9
105.9
95.9
92.6
80.2
115.9
89.8
TOTAL
579.9
376.3
95.9
351.8
339.4
262.5
238.9
Sources: Table prepared by CRS based on FY2021 Navy budget submission, committee and conference reports,
and explanatory statements on the FY2021 National Defense Authorization Act and the FY2021 DOD
Appropriations Act.
Notes: LUSV is Project 3066 within PE (Program Element) 0603178N (line 27 in the Navy’s FY2021 research
and development account). MUSV is Project 3428 within PE 0603178N (line 27). LUSV and MUSV enabling
technologies is Project 3067 within PE 0603178N (line 27). XLUUV is Project 3394 within PE 0604536N (line
89). HASC is House Armed Services Committee; SASC is Senate Armed Services Committee; HAC is House
Appropriations Committee; SAC is Senate Appropriations Committee; Conf. is conference agreement.
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FY2021 National Defense Authorization Act (H.R. 6395/S. 4049/P.L.
116-283)

House
The House Armed Services Committee, in its report (H.Rept. 116-442 of July 9, 2020) on H.R.
6395, recommended the funding levels shown in the HASC column of Table 2. A recommended
reduction of $238.6 mil ion (the entire requested amount) for LUSV is for “Two additional
Overlord vessels [being] excess to need.” A recommended increase of $45.0 mil ion is for
converting two Navy Expeditionary Fast Transport ships (EPF) into LUSV prototypes. (Page
391) A recommended reduction of $10 mil ion for XLUUV is for “XLUUV late test and
evaluation award.” (Page 393)
Regarding the recommended funding for converting two EPFs into LUSV prototypes, H.Rept.
116-442 states
Expeditionary Fast Transport conversion to an unmanned surface vessel
The committee recognizes that unmanned surface vessels will play an essential role in
future fleets of the Navy and supports the development of this capability in a manner that
responsibly fields this new capability. The committee continues to believe that the Navy’s
current acquisition strategy incorporates an excessive amount of concurrency and is overly
focused on the hull. The desire to move immed iately from development into serial
production will only yield similar misfortunes as past shipbuilding programs with similar
strategies. The committee believes the Navy should be primarily focused on the autonomy
piece of this capability and ensuring that technologies that will need to be developed to
support autonomous operations are mature before being incorporated on a purpose built
vessel. A strategy that includes prototyping and test-of-ship systems such as propulsion,
Command, Control, Communications, Computers and Intelligence, and other major Hull,
Mechanical and Engineering systems prior to hull form decisions is a more prudent strategy
that may actually field this capability sooner. The committee is also concerned with what
level of manning if any will be required for these vessels. In briefings, the Navy has stated
that initially these vessels will need to be minimally manned rather than fully unmanned in
order to maximize Concept of Operations (CONOPS) development. The committee
believes that the Navy should modify existing mature manned ships to support autonomous
operations in order to develop CONOPS rather than procuring new ships that will need to
support manned operations, but will eventually be fully unmanned.
Therefore, the committee recommends $45.0 million in PE 0603178N for the conversion
of two Expeditionary Fast Transport (EPF) ships to support autonomous operations and
accelerate CONOPS development. (Pages 43-44)
Section 230 of H.R. 6395 as reported by the committee states
SEC. 230. LIMITATIONS RELATING TO LARGE UNMANNED SURFACE VESSELS
AND ASSOCIATED OFFEN SIVE WEAPON SYSTEMS.
(a) LIMITATION ON AVAILABILITY OF FUNDS FOR LUSV.—
(1) LIMITATION.—None of the funds authorized to be appropriated by this Act or
otherwise made available for fiscal year 2021 for the Department of the Navy for the
procurement of a large unmanned surface vessel may be obligated or expended until a
period of 60 days has elapsed following the date on which the Secretary of the Navy
submits to the congressional defense committees the certification described in paragraph
(2).
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(2) CERTIFICATION DESCRIBED.—The certification described in this paragraph is a
written statement of the Secretary of the Navy certifying, with respect to any large
unmanned surface vessel to be procured by the Secretary, the following:
(A) A hull system, a mechanical system, and an electrical system have been developed for
the vessel and each system—
(i) has attained a technology readiness level of seven or greater; and
(ii) can be operated autonomously for a minimum of 30 days.
(B) A command control system has been developed for the vessel and the system—
(i) can be operated autonomously;
(ii) includes autonomous detection; and
(iii) has attained a technology readiness level of seven or greater.
(C) A detailed plan has been developed for measuring and demonstrating the reliability of
the vessel.
(D) All payloads expected to be carried on the vessel have attained a technology readiness
level of seven or greater.
(b) LIMITATION ON LUSV WEAPON INTEGRATION.—
The Secretary of the Navy may not integrate any offensive weapon system into a large
unmanned surface vessel until the date on which the Secretary of the Defense certifies to
the congressional defense committees that any large unmanned surface vessel that employs
offensive weapons will comply with the law of armed conflict. Such certification shal
include a detailed explanation of how such compliance will be achieved.
Senate
The Senate Armed Services Committee, in its report (S.Rept. 116-236 of June 24, 2020) on S.
4049, recommended the funding levels shown in the SASC column of Table 2. The
recommended reductions to zero funding line 27 is for “Excess procurement ahead of satisfactory
testing.” (Page 504) The recommended reduction of $20 mil ion for line 89 is for “Orca UUV
[XLUUV] testing delay and uncertified test strategy” ($10.0 mil ion) and “Snakehead UUV
uncertified test strategy” ($10 mil ion). (Page 507)
Section 122 of S. 4049 as reported by the committee states
SEC. 122. LIMITATION ON NAVY MEDIUM AND LARGE UNMANNED SURFACE
VESSELS.
(a) MILESTONE B APPROVAL REQUIREMENTS.—Milestone B approval may not be
granted for a covered program unless such program accomplishes prior to and incorporates
into such approval—
(1) qualification by the Senior Technical Authority of—
(A) at least two different main propulsion engines and ancillary equipment, including the
fuel and lube oil systems; and
(B) at least two different electrical genera tors and ancillary equipment;
(2) final results of test programs of engineering development models or prototypes for
critical systems specified by the Senior Technical Authority in their final form, fit, and
function and in a realistic environment; and
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(3) a determination by the milestone decision authority of the minimum number of vessels,
discrete test events, performance parameters to be tested, and schedule require d to
complete initial operational test and evaluation and demonstrate operational suitability and
operational effectiveness.
(b) QUALIFICATION REQUIREMENTS.—The qualification required in subsection
(a)(1) shall include a land-based operational demonstration of such equipment in the
vessel-representative form, fit, and function for not less than 1,080 continuous hours
without preventative maintenance, corrective maintenance, emergent repair, or any other
form of repair or maintenance.
(c) REQUIREMENT TO USE QUALIFIED ENGINES AND GENERATORS.—The
Secretary of the Navy shall require that covered programs use only main propulsion
engines and electrical generators that are qualified under sub section (a)(1).
(d) LIMITATION.—The Secretary of the Navy may not release a detail design or
construction request for proposals or obligate funds from a procurement account for a
covered program until such program receives Milestone B approval and the milestone
decision authority notifies the congressional defense committees, in writing, of the actions
taken to comply with the requirements under this section.
(e) DEFINITIONS.—In this section:
(1) The term ‘‘covered program’’ means a program for—
(A) medium unmanned surface vessels; or
(B) large unmanned surface vessels.
(2) The term ‘‘Milestone B approval’’ has the meaning given the term in section 2366(e)(7)
of title 10, United States Code.
(3) The term ‘‘milestone decision authority’’ means the official within the Department of
Defense designated with the overall responsibility and authority for acquisition decisions
for the program, including authority to approve entry of the program into the next phase of
the acquisition process.
(4) The term ‘‘Senior Technical Authority’’ has the meaning given the term in section
8669b of title 10, United States Code.
Regarding Section 122, S.Rept. 116-236 states
Limitation on Navy medium and large unmanned surface vessels (sec. 122)
The committee recommends a provision that would require that certain technical conditions
be met prior to Milestone B approval for medium and large unmanned surface vessels.
The committee notes that the budget request provides for the prototyping and testing of
Medium and Large Unmanned Surface Vessels (MUSVs and LUSVs), including
procurement of up to two additional LUSVs in conjunction with a Strategic Capabilities
Office (SCO) initiative. The committee understands that the four LUSVs procured by the
SCO beginning in fiscal year 2018, at a cost of more than $510 million, are sufficient to
achieve the objectives of the SCO initiative, which is scheduled to be completed in the
fourth quarter of fiscal year 2021.
The committee further notes that the budget request includes plans to award the LUSV
Detail Design and Construction (DD&C) contract in fiscal year 2022 and transition LUSV
to a program of record in fiscal year 2023.
The committee remains concerned that the budget request’s concurrent approach to LUSV
design, technology development, and integration as well as a limited understanding of the
LUSV concept of employment, requirements, and reliability for envisioned missions pose
excessive acquisition risk for additional LUSV procurement in fiscal year 2021. The
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committee is also concerned by the unclear policy implications of LUSVs, including ill-
defined international unmanned surface vessel standards and the legal status of armed or
potentially armed LUSVs.
Additionally, the committee notes that the Navy’s most recent shipbuilding plan, ‘‘Report
to Congress on the Annual Long-Range Plan for Construction of Naval Vessels for Fiscal
Year 2020,’’ acknowledges similar issues: ‘‘Unmanned and optionally-manned systems
are not accounted for in the overall battle force[.] ... The physical challenges of extended
operations at sea across the spectrum of competition and conflict, the concepts of
operations for these platforms, and the policy challenges associated with employing deadly
force from autonomous vehicles must be well understood prior to replacing accountable
battle force ships.’’
The committee believes that further procurement of MUSVs and LUSVs should occur only
after the lessons learned from the current SCO initiative have been incorporated into the
system specification and additional risk reduction actions are taken.
A specific area of technical concern for the committee is the Navy requirement for MUSVs
and LUSVs to operate continuously at sea for at least 30 days without preventative
maintenance, corrective maintenance, or emergent repairs. The committee is unaware of
any unmanned vessel of the size or complexity envisioned for MUSV or LUSV that has
demonstrated at least 30 days of such operation.
The committee understands that the SCO prototype vessels that are intended to provide
risk reduction for this program have demonstrated between 2 to 3 days of continuous
operation. The committee also understands that the SCO vessels are approximately 25
percent the size by tonnage of a LUSV, which may limit the applicability of lessons learned
and risk reduction from the SCO vessels to the MUSV and LUSV programs. Among other
critical subsystems, the committee views the main engines and electrical generators as key
USV mechanical and electrical subsystems whose reliability is critical to ensuring
successful operations at sea for at least 30 continuous days.
Accordingly, this provision would require at least two main engines and electrical
generators, including ancillary equipment, to be formally qualified by the Navy, including
a successful demonstration of at least 30 days of continuous operation prior to the LUSV
or MUSV Milestone B approval and would require the use of such engines and generators
in future USVs. The provision would also require the Senior Technical Authority and
Milestone Decision Authority to take additional actions related to reducing the technical
risk of these programs prior to a Milestone B approval.
The committee views the qualification of these critical subsystems as an essential
prototyping step necessary to provide a solid technical foundation for the MUSV and
LUSV programs. Rather than delaying these programs, the committee believes that
qualified engines and generators will enable the delivery of capable, reliable, and
sustainable USVs that meet the needs of fleet commanders faster than the plan contained
in the budget request. (Pages 9-10)
Section 237 of S. 4049 as reported by the committee states
SEC. 237. LIMITATION ON CONTRACT AWARDS FOR CERTAIN UNMANNED
VESSELS.
(a) LIMITATION.—None of the funds authorized to be appropriated for fiscal year 2021
by section 201 for research, development, test, and evaluation may be used for the award
of a contract for a covered vessel until the date that is 30 days after the date on which the
Under Secretary of Defense for Research and Engineering submits to the congressional
defense committees a report and certification described in subsection (c) for such contract
and covered vessel.
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(b) COVERED VESSELS.—For purposes of this section, a covered vessel is one of the
following:
(1) A large unmanned surface vessel (LUSV).
(2) A medium unmanned surface vehicle (MUSV).
(3) A large displacement unmanned undersea vehicle (LDUUV).
(4) An extra-large unmanned undersea vehicle (XLUUV).
(c) REPORT AND CERTIFICATION DESCRIBED.—A report and certification
described in this subsection regarding a contract for a covered vessel is —
(1) a report—
(A) submitted to the congressional defense committees not later than 60 days after the date
of the completion of an independent technical risk assessment for such covered vessel; and
(B) on the findings of the Under Secretary with respect to such assessment; and
(2) a certification, submitted to the congressional defense committees with the report
described in paragraph (1), that certifies that—
(A) the Under Secretary has determined, in conjunction with the Senior Technical
Authority designated under section 8669b(a)(1) of title 10, United States Code, for the class
of naval vessels that includes the covered vessel, that the critical mission, hull, mechanical,
and electrical subsystems of the covered vessel—
(i) have been demonstrated in vessel representative form, fit, and function; and
(ii) have achieved performance levels equal to or greater than applicable Department of
Defense threshold requirements for such class of vessels; and
(B) such contract is necessary to meet Department research, development, test, and
evaluation objectives for such covered vessel that cannot otherwise be met through further
land-based subsystem prototyping or other demonstration approaches.
(d)
CRITICAL
MISSION,
HULL,
MECHANICAL,
AND
ELECTRICA L
SUBSYSTEMS DEFINED.—In this section, the term ‘‘critical mission, hull, mechanical,
and electrical subsystems’’, with respect to a covered vessel, includes the following
subsystems:
(1) Command, control, communications, computers, intelligence, surveillance, and
reconnaissance.
(2) Autonomous vessel navigation, vessel control, contact management, and contact
avoidance.
(3) Communications security, including cryptopgraphy, encryption, and decryption.
(4) Main engines, including the lube oil, fuel oil, and other supporting systems.
(5) Electrical generation and distribution, including supporting systems.
(6) Military payloads.
(7) Any other subsystem identified as critical by the Senior Technical Authority designated
under section 8669b(a)(1) of title 10, United States Code, for the class of naval vessels that
includes the cov red vessel.
Regarding Section 237, S.Rept. 116-236 states
Limitation on contract awards for certain unmanned vessels (sec. 237)
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The committee recommends a provision that would require the submission of a
certification by the Under Secretary of Defense for Research and Engineering to the
congressional defense committees prior to the Department of Defense’s contracting for
certain vessels.
The committee is concerned that an excessive number of unmanned surface an d undersea
vessels (USVs and UUVs) are being acquired prematurely using Research, Development,
Test, and Evaluation funds and that these vessels may include subsystems that lack
sufficient technical reliability and technological maturity to allow the vesse ls to meet
threshold requirements.
The committee seeks to avoid contracting for USVs and UUVs when the technical
reliability and technological maturity of subsystems critical to propulsion and electrical
distribution or the military purposes of the vessels are either unknown or known to be
insufficient. For example, the committee notes the Navy requirement for Medium and
Large USVs (MUSV and LUSV) to operate continuously at sea for at least 30 days without
preventative maintenance, corrective maintenance, or emergent repairs. The committee is
unaware of any unmanned vessel of the size or complexity envisioned for MUSV or LUSV
that has demonstrated at least 30 days of such operation.
The committee understands that the Strategic Capabilities Office (SCO) proto type vessels
intended to provide risk reduction for the Navy’s LUSV program have demonstrated a
maximum of 2 to 3 days of continuous operation. The committee also understands that the
SCO vessels are approximately 25 percent the size by tonnage of a Navy LUSV. As a
result, the committee is concerned that the applicability of lessons learned and risk
reduction from the SCO vessels to the Navy MUSV and LUSV programs will be limited.
The committee views prior and successful land-based prototyping of individual critical
subsystems as essential to providing a solid technical foundation for USV and UUV
programs. Rather than delaying these programs, the committee believes that a deliberate
engineering-based subsystem prototyping approach will enable the delivery of capable,
reliable, and sustainable USVs and UUVs that meet the needs of fleet commanders faster
than the plan contained in the budget request, which assumes that several unproven or
nonexistent subsystems will rapidly materialize to meet the Navy’s requirements for these
vessels. (Pages 76-77)
S.Rept. 116-236 also states
Testbed for autonomous ship systems
The budget request included $122.3 million in Research, Development, Test, and
Evaluation (RDT&E), Navy, for PE 62123N Force Protection Applied Research.
The committee notes that a key technology gap for long -duration autonomous ship
operation lies in the robustness and resiliency of the hull and machinery plant. The
committee also notes that autonomous ships will be expected to operate for months
between human-assisted maintenance and that autonomous machinery must be robust and
resilient in order to avoid failure, repair damage, or redirect platforms as needed. The
committee notes the development of digital-twin technologies that allow for predictive or
automated maintenance and improved operations and logistics and help fill a critical gap
that has been identified in autonomous systems.
Therefore, the committee recommends an increase of $3.0 million, in RDT&E, Navy, for
PE 62123N for the development of a testbed for autonomous ship systems. (Page 95)
S.Rept. 116-236 also states
Unmanned surface vessel development
The budget request included $21.5 billion in Research, Development, Test, and Evaluation
(RDT&E), Navy, of which $464.0 million was for PE 63178N Medium and Large
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Unmanned Surface Vehicles and $38.4 million was for PE 63573N Advanced Surface
Machinery Systems.
The committee notes that the budget request provides for the prototyping and testing of
Medium and Large Unmanned Surface Vessels (MUSVs and LUSVs), including
procurement of up to two additional LUSVs in conjunction with a Strategic Capabilities
Office (SCO) initiative. The committee understands that the 4 LUSVs procured by the SCO
beginning in fiscal year 2018, at a cost of more than $510 million, are sufficient to achieve
the objectives of the SCO initiative, which is scheduled to be completed in the fourth
quarter of fiscal year 2021.
The committee believes that further procurement of MUSVs and LUSVs should occur only
after the lessons learned from the current SCO initiative have been incorporated into the
system specification and additional risk reduction actions are taken.
A specific area of technical concern for the committee is the Navy requirement for MUSVs
and LUSVs to operate continuously at sea for at least 30 days without preventative
maintenance, corrective maintenance, or emergent repairs. The committee is unaware of
any unmanned vessel of the size or complexity envisioned for MUSV or LUSV that has
demonstrated at least 30 days of such operation.
The committee understands that the SCO prototype vessels that are intended to provide
risk reduction for these programs have demonstrated between 2 to 3 days of continuous
operation. The committee also understands that the SCO vessels are approximately 25
percent the size by tonnage of a LUSV, which may limit the applicability of lessons learned
and risk reduction from the SCO vessels to the MUSV and LUSV programs. Among other
critical subsystems, the committee views the main engines and electrical generators in
particular as key USV mechanical and electrical subsystems whose reliability is critical to
ensuring successful operations at sea for at least 30 continuous days.
The committee also notes that additional funding is necessary to accelerate completion of
the Integrated Power and Energy Systems test facility (ITF) to achieve full test capability
in fiscal year 2023, consistent with section 131 of the National Defense Authorization Act
for Fiscal Year 2020 (Public Law 116–92), as well as the qualification of silicon carbide
power modules.
Accordingly, the committee recommends a decrease of $464.0 million, for a total of $0, in
RDT&E, Navy, for PE 63178N, and an increase of $200.0 million, for a total of $238.4
million in RDT&E, Navy, for PE 63573N.
The committee’s intent is that the increased funding in PE 63178N be used for: the USV
main engine and electrical generator qualification testing directed elsewhere in this Act
($70.0 million); USV autonomy development, which may include conversion of existing
vessels ($45.0 million); accelerating ITF testing ($75.0 million); and accelerating the
qualification of silicon carbide power modules ($10.0 million). (Pages 97-98)
S.Rept. 116-236 also states
Advanced undersea prototyping
The budget request included $21.5 billion in Research, Development, Test, and Evaluation
(RDT&E), Navy, of which $115.9 million was for PE 64536N advanced undersea
prototyping.
The committee notes that the Snakehead and Orca [XLUUV] test strategies require updates
to enable certification by the Director of Operational Test and Evaluation in accordance
with the Senate report accompanying the Department of Defense Appropriations Bill,
2020, incorporated into the Consolidated Appropriations Act, 2020 (S. Rept. 116–103).
Additionally, the committee is aware of Orca testing delays.
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Accordingly, the committee recommends a decrease of $20.0 million, for a total of $95.9
million, in RDT&E, Navy, for PE 64536N. (Page 100)
A September 14, 2020, letter and enclosure from the Office of Budget Management (OMB) to the
chairmen and ranking members of the Senate and House Armed Services Committee about
concerns that the Administration has with certain provisions in S. 4049 stated in part:
The Administration strongly objects to the absence of authorization language and funding
to procure critical prototype vessels. The Administration believes that rigorous land-and
sea-based testing is needed for a successful Large Unmanned Surface Vessel Program
(LUSV), providing a lethal, distributed new capability to the fleet. These funds are critical
to reduce risk and conduct integration and testing to ensure DOD is postured to transition
LUSV to a program of record in FY 2023. The Administration urges Congress to fuly
support this critical capability at the levels in the FY 2021 President’s Budget Request.58
Conference
The conference report (H.Rept. 116-617 of December 3, 2020) on H.R. 6395/P.L. 116-283 of
January 1, 2021, recommends the funding levels shown in the authorization conference column of
Table 2. The recommended reduction of $204.8 mil ion for line 27 is for “LUSV additional
prototypes’ ($159.3 mil ion) and “Unmanned surface vehicle enabling capabilities—payload
program reduction” ($45.5 mil ion). (PDF pages 4322-4323 of 4517) The recommended
reduction of $23.256 mil ion for line 89 is for “Excess scope adjustments.” (PDF page 4326 of
4517)
Section 122 of the conference version of H.R. 6395 states:
SEC. 122. LIMITATIONS ON NAVY MEDIUM AND LARGE UNMANNED
SURFACE VESSELS.
(a) MILESTONE B APPROVAL REQUIREMENTS.—Milestone B approval may not be
granted for a covered program unless such program accomplishes prior to and incorporates
into such approval—
(1) qualification by the Senior Technical Authority of—
(A) at least one representative main propulsion system, including the fuel and lube oil
systems; and
(B) at least one representative electrical generation and distribution system;
(2) final results of test programs of engineering development models or prototypes showing
that critical systems designated pursuant to subparagraph (C) of section 8669b(c)(2) of title
10, United States Code, are demonstrated as required by subparagraph (I) of that section;
and (3) a determination by the milestone decision authority of the minimum number of
vessels, discrete test events, performance parameters to be tested, and schedule required to
complete initial operational test and evaluation and demonstrate operational suitability and
operational effectiveness.
(b) QUALIFICATION REQUIRES OPERATIONAL DEMONSTRATION.—The
qualification required in subsection (a)(1) shall include a land-based operational
demonstration of the systems concerned in the vessel-representative form, fit, and function

58 Letter dated September 14, 2020, from Russell T . Vought, Director, Office of Management and Budget, to Senator
James M. Inhofe, Senator Jack Reed, Representative Adam Smith, and Representative Mac T hornberry with respect to
the National Defense Authorization Act (NDAA) for FY2021, PDF page 9 of 14, accessed September 17, 2020, at
https://www.whitehouse.gov/omb/legislative/letters/.
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for not less than 720 continuous hours without preventative maintenance, corrective
maintenance, emergent repair, or any other form of repair or maintenance.
(c) USE OF QUALIFIED SYSTEMS.—The Secretary of the Navy shall require that
covered programs use only main propulsion systems and electrical generation and
distribution systems that are qualified under subsection (a)(1).
(d) LIMITATION ON CONTRACT AWARD OR FUNDING.—
(1) IN GENERAL.—The Secretary may not award a detail design or construction contract,
or obligate funds from a procurement account, for a covered program until such program
receives Milestone B approval and the milestone decision authority notifies the
congressional defense committees, in writing, of the actions taken to comply with the
requirements under this section.
(2) EXCEPTION.—The limitation in paragraph (1) does not apply to advanced
procurement for government-furnished equipment.
(e) DEFINITIONS.—In this section:
(1) COVERED PROGRAM.—The term ‘‘covered program’’ means a program for—
(A) medium unmanned surface vessels; or
(B) large unmanned surface vessels.
(2) MILESTONE B APPROVAL.—The term ‘‘Milestone B approval’’ has the meaning
given the term in section 2366(e)(7) of title 10, United States Code.
(3) MILESTONE DECISION AUTHORITY.—The term ‘‘milestone decision authority’’
means the official within the Department of Defense designated with the overal
responsibility and authority for acquisition decisions for an acquisition program, including
authority to approve entry of the program into the next phase of the acquisition process.
(4) SENIOR TECHNICAL AUTHORITY.—The term ‘‘Senior Technical Authority’’ has
the meaning provided for in section 8669b of title 10, United States Code.
Regarding Section 122, H.Rept. 116-617 states:
Limitations on Navy medium and large unmanned surface vessels (sec. 122)
The Senate amendment contained a provision (sec. 122) that would require that certain
technical conditions be met prior to Milestone B approval for medium and large unmanned
surface vessels.
The House bill contained no similar provision.
The House recedes with an amendment that would reduce the minimum number of certain
systems to be qualified and the period of continuous operation of such systems to satisfy
qualification requirements, as well as allow the Secretary of the Navy to release certain
requests for proposals and contract for certain government furnished equipment prior to
Milestone B approval for medium and large unmanned surface vessels. (PDF page 3730 of
4517)
Section 227 of the conference version of H.R. 6395 states:
SEC. 227. LIMITATION ON CONTRACT AWARDS FOR CERTAIN UNMANNED
VESSELS.
(a) LIMITATION.—Not less than 30 days before awarding a contract using any funds from
the Research, Development, Test, and Evaluation, Navy account for the purchase of a
covered vessel, the Secretary of the Navy shall submit to the congressional defense
committees a report and certification described in subsection (c) for such contract and
covered vessel.
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(b) COVERED VESSELS.—For purposes of this section, a covered vessel is one of the
following:
(1) A large unmanned surface vessel (LUSV).
(2) A medium unmanned surface vehicle (MUSV).
(c) REPORT AND CERTIFICATION DESCRIBED.—A report and certification
described in this subsection regarding a contract for a covered vessel is —
(1) a report—
(A) submitted to the congressional defense committees not later than 60 days after the date
of the completion of an independent technical risk assessment for such covered vessel;
(B) on the findings and recommendations of the Senior Technical Authority for the class
of naval vessels that includes the covered vessel with respect to such assessment; and
(C) that includes such assessment; and
(2) a certification, submitted to the congressional defense committees with the report
described in paragraph (1), that certifies that—
(A) the Secretary has determined, in conjunction with the Senior Technical Authority for
the class of naval vessels that includes the covered vessel, that the critical mission, hul,
mechanical, and electrical subsystems of the covered vessel—
(i) have been demonstrated in vessel representative form, fit, and function; and
(ii) have achieved performance levels equal to or greater than applicable Depart
ment of Defense threshold requirements for such class of vessels or have maturation plans
in place to achieve such performance levels prior to transition to a program of record,
including a detailed description of such achieved performance or maturation plans; and
(B) such contract is necessary to meet Department research, development, test, and
evaluation objectives for such covered vessel that cannot otherwise be met through further
land based subsystem prototyping or other demonstration approaches.
(d) LIMITATION ON WEAPON INTEGRATION.—
(1) IN GENERAL.—The Secretary may not integrate any offensive weapon system into a
covered vessel until the date that is 30 days after the date on which the Secretary of the
Defense certifies to the congressional defense committees that such covered vessel—
(A) will comply with applicable laws, including the law of armed conflict, with a detailed
explanation of how such compliance will be achieved; and
(B) has been determined to be the most appropriate surface vessel to meet applicable of
fensive military requirements.
(2) COMPLETION OF ANALYSIS OF ALTERNATIVES REQUIRED.—A
determination under paragraph (1)(B) shall be made only after the completion of an
analysis of alternatives that—
(A) is described in subsection (e)(1); and
(B) supports such determination.
(e) SUBMITTAL OF ANALYSIS OF ALTERNATIVES TO CONGRESS.—
(1) ANALYSIS OF ALTERNATIVES REQUIRED.—Not later than one year after the
date of the enactment of this Act, the Secretary shall s ubmit to the congressional defense
committees an analysis of alternatives regarding covered vessels with an integrated
offensive weapon system and the most appropriate surface vessels to meet applicable
offensive military requirements.
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(2) CONTENTS.—The analysis submitted under paragraph (1) shall include, at a
minimum, the following elements:
(A) Identification of capability needs applicable to such covered vessels, including
offensive strike capability and capacity from the Mark–41 vertical launch system.
(B) Projected threats.
(C) Projected operational environments.
(D) Projected operational concepts.
(E) Projected operational requirements.
(F) Status quo (baseline) and surface vessel alternatives able to meet the capability needs
identified in subparagraph (A), including—
(i) modified naval vessel designs, including amphibious ships, expeditionary fast
transports, and expeditionary sea bases;
(ii) modified commercial vessel designs, including container ships and bulk carriers;
(iii) new naval vessel designs; and
(iv) new commercial vessel designs.
(G) Vessel design, performance, and measures of effectiveness of the baseline and each
alternative, including a description of critical mission, hull, mechanical, and electrical
subsystems.
(H) Estimated research, development, test, and evaluation cost of baseline and each
alternative.
(I) Estimated lead vessel and average follow-on vessel procurement costs of baseline and
each alternative.
(J) Life-cycle costs of baseline and each alternative.
(K) Life-cycle cost per baseline vessel and each alternative vessel.
(L) Life-cycle cost per specified quantity of baseline vessels and alternative vessels.
(M) Technology readiness assessment of baseline and each alternative.
(N) Analysis of alternatives, including relative cost and capability performance of base line
and alternative vessels.
(O) Trade-off analysis.
(P) Sensitivity analysis.
(Q) Conclusions and recommendations, which if the Secretary of Defense deems it
appropriate, shall include the determination required under subsection (d)(1)(B).
(f) DEFINITIONS.—In this section:
(1) The term ‘‘critical mission, hull, mechanical, and electrical subsystems’’, with respect
to a covered vessel, includes the following subsystems:
(A) Command, control, communications, computers, intelligence, surveillance, and
reconnaissance.
(B) Autonomous vessel navigation, vessel control, contact management, and contact
avoidance.
(C) Communications security, including cryptopgraphy, encryption, and decryption.
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(D) Main engines, including the lube oil, fuel oil, and other supporting systems.
(E) Electrical generation and distribution, including supporting systems.
(F) Military payloads.
(G) Any other subsystem identified as critical by the Senior Technical Authority for the
class of naval vessels that includes the covered vessel.
(2) The term ‘‘Senior Technical Authority’’ means, with respect to a class of naval vessels,
the Senior Technical Authority designated for that class of naval vessels under section
8669b of title 10, United States Code.
Regarding Section 227, H.Rept. 116-617 states:
Limitation on contract awards for certain unmanned vessels (sec. 227)
The House bill contained a provision (sec. 230) that would prohibit the procurement of any
large unmanned surface vessels in fiscal year 2021 until a certification regarding
technology maturity has been submitted to the Congress, as well as prohibit the inclusion
of offensive weapons systems in such vessels until the Secretary of Defense certifies how
these systems will comply with the Law of Armed Conflict.
The Senate amendment contained a similar provision (sec. 237) that would require the
submission of a certification by the Under Secretary of Defense for Research and
Engineering prior to contracting for certain vessels.
The House recedes with an amendment that would change the submitter of the certification
to the Secretary of the Navy, remove unmanned underwater vehicles as covered vessels,
and add a limitation on the integration of offensive weapons into covered vessels until an
analysis of alternatives is conducted and a Secretary of Defense certification is made. (PDF
page 3763 of 4517)
FY2021 DOD Appropriations Act (H.R. 7617/S. XXXX/Division C of
H.R. 133/P.L. 116-260)

House
The House Appropriations Committee, in its report (H.Rept. 116-453 of July 16, 2020) on H.R.
7617, recommended the funding levels shown in the HAC column of Table 2. A recommended
reduction of $159.3 mil ion for LUSV is for “LUSV additional prototypes.” (Page 266) A
recommended reduction of $45.5 mil ion for LUSV and MUSV enabling technologies is for
“Unmanned surface vehicle enabling capabilities—payload program reduction.” (Page 266) The
recommended reduction of $35.626 mil ion for line 89 is for “Test and evaluation delays.” (Page
268)
Senate
The Senate Appropriations Committee, in the explanatory statement for S. XXXX that the
committee released on November 10, 2020, recommended the funding levels shown in the SAC
column of Table 2. The recommended reduction of $372.842 mil ion to line 27 reflects a
restructuring of funding for the LUSV and MUSV programs and their enabling technologies
involving seven changes to requested funding levels, including three transfers of funding totaling
$55.402 mil ion to a newly created line 27A for MUSVs. (Pages 185-186) The committee
recommended a reduction of $23.256 mil ion to line 89 for “Restoring acquisition accountability:
Excess scope adjustments.” (Page 187).
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The committee’s explanatory statement states:
Unmanned Surface Vessels.—The fiscal year 2021 President’s budget request includes
$437,740,000 for the procurement of two Large Unmanned Surface Vessels [LUSVs] and
containerized payloads, as well as for the development of a modified combat system and
enabling capabilities to prototype and demonstrate technologies in support o f a LUSV
program of record in fiscal year 2023 that includes an integrated Vertical Launch System
[VLS] payload. Additionally, the fiscal year 2021 President’s budget request includes
$26,302,000 to complete detailed design and oversight of a prototype Med ium Unmanned
Surface Vessel [MUSV] that carries non-kinetic payloads, and the Navy has budgeted
funds for the procurement of an additional MUSV in fiscal year 2023. Subsequent to the
budget submission, the Navy revised its fiscal year 2021 acquisition and budget requests
for both the LUSV and MUSV programs and requested that funds be appropriated for the
first year of a two-year Comprehensive Reliability Plan [CRP] for both programs in lieu of
additional LUSV platforms and payloads, while maintaining the Na vy’s previously
planned fiscal year 2023 establishment of a LUSV program of record with an integrated
VLS.
The Committee notes that the mission requirements and concepts of operations for the
LUSV and MUSV programs remain an evolving work in progress, and that concerns
previously expressed by the appropriations committees with respect to a VLS payload on
a LUSV have not been sufficiently addressed. However, the Committee does believe that
demonstrating the reliability of some key technologies of unmanned su rface vessels is
critical to acquisition success of any such platforms.
As such, the Committee recommends fully funding the MUSV program in fiscal year 2021,
to include the Navy’s requested realignment of $29,100,000 from LUSV to the MUSV
program in support of a MUSV CRP. The Committee also recommends full funding for
the development of enabling capabilities such as autonomy, command and control, sensors,
and experimentation. The Committee recommends no funding for additional LUSVs, a
LUSV combat system, combat system modifications, or LUSV payloads in fiscal year
2021. The Committee notes that the Navy will take possession of two prototype LUSVs
from the Strategic Capabilities Office at the end of fiscal year 2021 and that in fiscal year
2020, Congress appropriated funding for two additional LUSVs to the Navy that are also
scheduled to deliver to the Navy at the end of fiscal year 2021. The Committee believes
that the Navy has sufficient prototypes on-hand to define LUSV and MUSV missions,
program requirements, and concepts of operations in alignment with key stakeholders.
Finally, Congress in fiscal year 2020 appropriated funding for concept design studies to
inform future detail design and construction of a LUSV and recommends an additional
$10,000,000, as requested by the Navy, in fiscal year 2021 for these efforts. The Committee
notes that this does not constitute endorsement of integrating VLS on LUSVs. (Pages 191-
192)
Conference
The explanatory statement for the final version of the FY2021 DOD Appropriations Act (Division
C of H.R. 133/P.L. 116-260 of December 26, 2020, the Consolidated Appropriations Act, 2021)
provides the funding levels shown in the appropriation conference column of Table 2. The
reduction of $370.342 mil ion to line 27 reflects a restructuring of funding for the LUSV and
MUSV programs and their enabling technologies involving eight changes to requested funding
levels, including two transfers of funding totaling $55.402 mil ion to a newly created line 27A for
MUSVs. (PDF page 310 of 469) The reduction of $26.046 mil ion to line 89 is for “Test and
evaluation delays.” (PDF page 313 of 469)

Congressional Research Service
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Navy Large Unmanned Surface and Undersea Vehicles


Author Information

Ronald O'Rourke

Specialist in Naval Affairs



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Congressional Research Service
R45757 · VERSION 34 · UPDATED
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