Navy Large Unmanned Surface and Undersea 
June 21, 2019 
Vehicles: Background and Issues for Congress 
Ronald O'Rourke 
The Navy wants to develop and procure three new types of unmanned vehicles (UVs) in FY2020 
Specialist in Naval Affairs 
and beyond—Large Unmanned Surface Vehicles (LUSVs), Medium Unmanned Surface 
  
Vehicles (MUSVs), and Extra-Large Unmanned Undersea Vehicles (XLUUVs). The Navy is 
requesting $628.8 million in FY2020 research and development funding for these three UV 
 
programs and their enabling technologies. 
The Navy wants to acquire these three types of UVs (which this report refers to collectively as 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 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 emphasis that the Navy placed on UV programs in its FY2020 budget submission and the Navy’s desire to 
employ accelerated acquisition strategies in acquiring these large UVs together 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 LUSV program is a proposed new start project for FY2020. The Navy wants to procure two LUSVs per year in FY2020-
FY2024. 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. The Navy reportedly envisions LUSVs as being 200 feet to 300 feet in 
length and having a full load displacement of about 2,000 tons.  
The MUSV program began in FY2019. The Navy plans to award a contract for the first MUSV in FY2019 and wants to 
award a contract for the second MUSV in FY2023. 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 defines MUSVs as having a length of 
between 12 meters (about 39 feet) and 50 meters (about 164 feet). The Navy wants to pursue the MUSV program as a rapid 
prototyping effort under what is known as Section 804 acquisition authority. 
The XLUUV program, also known as Orca, was established to address a Joint Emergent Operational Need (JEON). The 
Navy wants to procure nine XLUUVs in FY2020-FY2024. The Navy announced on February 13, 2019, that it had selected 
Boeing to fabricate, test, and deliver the first four Orca XLUUVs and associated support elements. On March 27, 2019, the 
Navy announced that the award to Boeing had been expanded to include the fifth Orca. 
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 and funding method 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; the personnel implications of the programs; and whether the Navy has 
accurately priced the work it is proposing to do in FY2020 on the programs. 
Congressional Research Service 
 
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Contents 
Introduction ..................................................................................................................................... 1 
Background ..................................................................................................................................... 1 
Navy USVs and UUVs in General ............................................................................................ 1 
UVs in the Navy ................................................................................................................. 1 
Navy USV and UUV Categories......................................................................................... 2 
Large UVs and Navy Ship Count ....................................................................................... 2 
Part of More-Distributed Navy Fleet Architecture ............................................................. 4 
Highlighted in FY2020 Navy Budget ................................................................................. 8 
Accelerated Acquisition Strategies and Enabling Technologies ......................................... 9 
Large Navy USV and UUV Programs in Brief ........................................................................ 11 
Large Unmanned Surface Vehicle (LUSV) ........................................................................ 11 
Medium Unmanned Surface Vehicle (MUSV) ................................................................. 13 
Extra Large Unmanned Undersea Vehicle (XLUUV)....................................................... 14 
FY2020-FY2024 Funding ................................................................................................. 17 
Issues for Congress ........................................................................................................................ 18 
Analytical Basis for More-Distributed Fleet Architecture ...................................................... 18 
Accelerated Acquisition Strategies and Funding Method ....................................................... 18 
Technical, Schedule, and Cost Risk ........................................................................................ 19 
Annual Procurement Rates ...................................................................................................... 19 
Industrial Base Implications .................................................................................................... 19 
Personnel Implications ............................................................................................................ 19 
FY2020 Funding ..................................................................................................................... 20 
Legislative Activity for FY2020 .................................................................................................... 20 
Summary of Congressional Action on FY2020 Funding Request .......................................... 20 
FY2020 National Defense Authorization Act (H.R. 2500/S. 1790) ........................................ 20 
House ................................................................................................................................ 20 
Senate ................................................................................................................................ 21 
FY2020 DOD Appropriations Act (H.R. 2968) ...................................................................... 22 
House ................................................................................................................................ 22 
 
Figures 
Figure 1. Navy USV Systems Vision .............................................................................................. 3 
Figure 2. Navy UUV Systems Vision .............................................................................................. 4 
Figure 3. Navy Briefing Slide on Surface Combatant Force Architecture ...................................... 5 
Figure 4. Proposed USV and UUV Annual Procurement Quantities .............................................. 9 
Figure 5. Enabling Technologies for USVs and UUVs .................................................................. 11 
Figure 6. Sea Hunter Medium Displacement USV ....................................................................... 15 
Figure 7. Boeing Echo Voyager UUV ........................................................................................... 16 
Figure 8. Boeing Echo Voyager UUV ........................................................................................... 16 
Figure 9. Boeing Echo Voyager UUV ........................................................................................... 17 
  
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Tables 
Table 1. FY2020-FY2024 Requested and Programmed Funding for Large UVs ......................... 18 
Table 2. Congressional Action on FY2020 Large UV Funding Request ....................................... 20 
  
Contacts 
Author Information ........................................................................................................................ 23 
 
Congressional Research Service 
Navy Large Unmanned Surface and Undersea Vehicles:  
 
Introduction 
This report provides background information and potential issues for Congress for three types of 
unmanned vehicles (UVs) that the Navy wants to develop and procure in FY2020 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 three types of 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 
distributed1 than the Navy’s current fleet architecture. The Navy is requesting $628.8 million in 
FY2020 research and development funding for these three UV programs and their enabling 
technologies, and the Navy’s FY2020 budget submission programs a total of $4,518.8 million 
(i.e., about $4.5 billion) for the programs and their enabling technologies during the period 
FY2020-FY2024. 
The issue for Congress is whether to approve, reject, or modify the Navy’s acquisition strategies 
and FY2020 funding requests for these three types of UVs. The Navy’s proposals for developing 
and procuring them pose a number of oversight issues for Congress. Congress’s decisions on 
these issues could substantially affect Navy capabilities and funding requirements and the 
shipbuilding and UV industrial bases. 
In this CRS report, the term large UVs refers to the three programs listed above. In addition to the 
large UVs covered in this report, the Navy also wants to develop and procure smaller USVs and 
UUVs, as well as unmanned aerial vehicles (UAVs) of various sizes. Other U.S. military services 
are developing, procuring, and operating their own types of UVs. Separate CRS reports address 
some of these efforts.2 
Background 
Navy USVs and UUVs in General 
UVs in the Navy 
UVs are one of several new capabilities—along with directed-energy weapons, hypersonic 
weapons, artificial intelligence, big data analytics, and cyber capabilities—that the Navy says it is 
pursuing to meet emerging military challenges, particularly from China.3 UVs can be equipped 
                                                 
1 As discussed later in this report, the more-distributed architecture, when compared to the current 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. 
2 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 
Autonomous Systems (RAS) and Artificial Intelligence (AI): Considerations for Congress, coordinated by Andrew 
Feickert.  
3 See, for example, Department of the Navy, Highlights of the Department of the Navy FY 2020 Budget, pp. 1-5, 1-8. 
For a CRS report on Navy lasers, electromagnetic railguns, and 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. 
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with sensors, weapons, or other payloads, and can be operated remotely, semi-autonomously, or 
(with technological advancements) autonomously.4 They can be individually less expensive to 
procure than manned ships and aircraft because their designs do not need to incorporate spaces 
and support equipment for onboard human operators. UVs can be 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-called “three D” missions, meaning missions 
that are “dull, dirty, or dangerous.”5 
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 about 4,000 aircraft 
included 41 UAVs at the end of FY2018 and is projected to include 99 UAVs at the end of 
FY2019.6 Even so, some observers have occasionally expressed dissatisfaction with what they 
view as the Navy’s slow pace in transitioning UV development efforts into programs for 
procuring UVs in quantity and integrating them into the operational fleet. 
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 calls large, medium, small, and very small, and its UUV 
acquisition programs similarly into four size-based categories that the Navy calls extra-large, 
large, medium, and small. The large UVs discussed in this CRS report fall into the top two USV 
categories in Figure 1 and the top UUV category in Figure 2. 
The smaller 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. 
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. Navy officials state that they have not yet 
decided whether to modify the top-level count of the number of ships in the Navy to include these 
large UVs. 
                                                 
4 For more on autonomous UVs, see CRS In Focus IF11150, Defense Primer: U.S. Policy on Lethal Autonomous 
Weapon Systems, by Kelley M. Sayler. 
5 See, for example, Ann Diab, “Drones Perform the Dull, Dirty, or Dangerous Work,” Tech.co, November 12, 2014; 
Bonnie Robinson, “Dull, Dirty, Dangerous Mission? Send in the Robot Vehicle,” U.S. Army, August 20, 2015; 
Bernard Marr, “The 4 Ds Of Robotization: Dull, Dirty, Dangerous And Dear,” Forbes, October 16, 2017. 
6 Department of the Navy, Highlights of the Department of the Navy FY 2020 Budget, Figure 3.7 on page 3-7. 
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Navy Large Unmanned Surface and Undersea Vehicles:  
 
Figure 1. Navy USV Systems Vision 
 
Source: Slide 3 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. 
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Figure 2. Navy UUV Systems Vision 
 
Source: Slide 2 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. 
Part of More-Distributed Navy Fleet Architecture 
The Navy wants to acquire the large UVs covered in this report as part of an effort to shift the 
Navy to a new fleet architecture that is more widely distributed than the Navy’s current 
architecture. Compared to the current fleet architecture, this more-distributed architecture is to 
include proportionately fewer large surface combatants (or LSCs, meaning cruisers and 
destroyers), proportionately more small surface combatants (or SSCs, meaning frigates and 
Littoral Combat Ships), and the addition of significant numbers of large UVs. 
Figure 3 provides, for the surface combatant portion of the Navy,7 a conceptual comparison of 
the current fleet architecture (shown on the left as the “ship centric force”) and the new, more-
distributed architecture (shown on the right as the “distributed/nodal force”). The figure does not 
depict the entire surface combatant fleet, but rather a representative portion of it. 
 
                                                 
7 Other major parts of the Navy include submarines, aircraft carriers, amphibious ships, logistics (resupply) ships, and 
support ships. 
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Figure 3. Navy Briefing Slide on Surface Combatant Force Architecture 
Each sphere represents a ship or a USV 
 
Source: Il ustration accompanying Megan Eckstein, “Sea Hunter Unmanned Ship Continues Autonomy Testing 
as NAVSEA Moves Forward with Draft RFP,” USNI News, April 29, 2019. 
Notes: Each sphere represents a ship or a USV. LSC means large surface combatant (i.e., cruiser or destroyer), 
and SSC means small surface combatant (i.e., frigate or Littoral Combat Ship). As shown in the color coding, the 
LSCs and SSCs are equipped with a combination of sensors (green), command and control (C2) equipment (red), 
and payloads other than sensors and C2 equipment, meaning principally weapons (blue). LUSVs and MUSVs, in 
contrast, are equipped primarily with weapons (blue) or sensors (green). 
In the figure, each sphere represents a manned ship or USV. (Since the illustration focuses on the 
surface combatant force, it does not include UUVs.) As shown in the color coding, under both the 
current fleet architecture and the more-distributed architecture, the manned ships (i.e., the LSCs 
and SSCs) are equipped with a combination of sensors (green), command and control (C2) 
equipment (red), and payloads other than sensors and C2 equipment, meaning principally 
weapons (blue). 
Under the more-distributed architecture, the manned ships would be on average smaller (because 
a greater share of them would be SSCs), and this would be possible because some of the surface 
combatant force’s weapons and sensors would be shifted from the manned ships to USVs, with 
weapon-equipped LUSVs acting as adjunct weapon magazines and sensor-equipped MUSVs 
contributing to the fleet’s sensor network. 
As shown in Figure 3, under the Navy’s current surface combatant force architecture, there are to 
be 20 LSCs for every 10 SSCs (i.e., a 2:1 ratio of LSCs to SSCs), with no significant contribution 
from LUSVs and MUSVs. This is consistent with the Navy’s current force-level objective, which 
calls for achieving a 355-ship fleet that includes 104 LSCs and 52 SSCs (a 2:1 ratio). Under the 
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more-distributed architecture, the ratio of LSCs to SSCs would be reversed, with 10 LSCs for 
every 20 SSCs (a 1:2 ratio), and there would also now be 30 LUSVs and 40 MUSVs. A January 
15, 2019, press report states: 
The Navy plans to spend this year taking the first few steps into a markedly different future, 
which, if it comes to pass, will upend how the fleet has fought since the Cold War. And it 
all starts with something that might seem counterintuitive: It’s looking to get smaller. 
“Today,  I  have  a  requirement  for  104  large  surface  combatants  in  the  force  structure 
assessment; [and] I have [a requirement for] 52 small surface combatants,” said Surface 
Warfare Director Rear Adm. Ronald Boxall. “That’s a little upside down. Should I push 
out  here  and  have  more  small  platforms?  I  think  the  future  fleet  architecture  study  has 
intimated ‘yes,’ and our war gaming shows there is value in that.”8 
Another way of summarizing Figure 3 would be to say that the surface combatant force 
architecture (reading vertically down the figure) would change from 20+10+0+0 (i.e., a total of 
30 surface combatant platforms, all manned) for a given portion of the surface combatant force, 
to 10+20+30+40 (i.e., a total of 100 surface combatant platforms, 70 of which would be LUSVs 
and MUSVs) for a given portion of the surface combatant force. The Navy refers to the more-
distributed architecture’s combination of LSCs, SSCs, LUSVs, and MUSVs as the Future Surface 
Combatant Force (FSCF). 
Figure 3 is conceptual, so the platform ratios for the more-distributed architecture should be 
understood as notional or approximate rather than exact. The point of the figure is not that 
relative platform numbers under the more-distributed architecture would change to the exact 
ratios shown in the figure, but that they would evolve over time toward something broadly 
resembling those ratios. 
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 maritime anti-access/area-denial (A2/AD) 
capabilities (particularly anti-ship missiles and their supporting detection and targeting systems) 
of potential adversaries, particularly China.9 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 adapting to changing 
mission needs.10 
                                                 
8 David B. Larter, “US Navy Moves Toward Unleashing Killer Robot Ships on the World’s Oceans,” Defense News, 
January 15, 2019. 
9 For more on China’s maritime A2/AD capabilities, see CRS Report RL33153, China Naval Modernization: 
Implications for U.S. Navy Capabilities—Background and Issues for Congress, by Ronald O'Rourke.  
10 For additional discussion, see CRS Report RL32665, Navy Force Structure and Shipbuilding Plans: Background and 
Issues for Congress, by Ronald O'Rourke. 
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For a number of years, Navy leaders acknowledged the views of those observers but continued to 
support the current fleet architecture. More recently, however, Navy leaders appear to have 
shifted their thinking, with comments from Navy officials like the one quoted above, Navy 
briefing slides like Figure 3, and the Navy’s emphasis on USVs and UUVs in its FY2020 budget 
submission (see next section) suggesting that Navy leaders now support moving the fleet to a 
more-distributed architecture. The views of Navy leaders appear to have shifted in favor of a 
more-distributed architecture because they now appear to believe that such an architecture will 
be: 
  increasingly needed—as the observers have long argued—to respond effectively 
to the improving maritime A2/AD capabilities of other countries, particularly 
China; 
  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 
  no more expensive, and possibly less expensive, than the current architecture. 
The more-distributed architecture that Navy leaders now appear to support may differ in its 
details from distributed architectures that the observers have been advocating, but the general idea 
of shifting to a more-distributed architecture, and of using large UVs as a principal means of 
achieving that, appears to be similar. The Department of Defense (DOD) states that 
The  FY  2020  budget  request  diversifies  and  expands  sea  power  strike  capacity  through 
procurement  of  offensively  armed  Unmanned  Surface  Vessels  (USVs).  The  USV 
investment, paired with increased investment in long-range maritime munitions, represents 
a  paradigm  shift  towards  a  more  balanced,  distributed,  lethal,  survivable,  and  cost-
imposing naval force that will better exploit adversary weaknesses and project power into 
contested environments.11 
The Navy’s FY2020 30-year shipbuilding plan mentions a new overarching operational concept 
for the Navy (i.e., a new general concept for how to employ Navy forces) called Distributed 
Maritime Operations (DMO).12 A December 2018 document from the Chief of Naval Operations 
states that the Navy will “Continue to mature the Distributed Maritime Operations (DMO) 
concept and key supporting concepts” and “Design and implement a comprehensive operational 
architecture to support DMO.”13 While Navy officials have provided few details in public about 
DMO,14 the Navy does state that “MUSV and LUSV are key enablers of the Navy’s Distributed 
Maritime Operations (DMO) concept, which includes being able to forward deploy (alone or in 
                                                 
11 Department of Defense, Office of the Undersecretary of Defense (Comptroller)/Chief Financial Officer, Defense 
Budget Overview, United States Department of Defense, Fical year 2020 Budget Request, March 2019, pp. 4-5 to 4-6. 
12 U.S. Navy, Report to Congress on the Annual Long-Range Plan for Construction of Naval Vessels for Fiscal Year 
2020, March 2019, pp. 3, 4, 7, 8, 15, 17, 24. 
13 U.S. Navy, Chief of Naval Operations, A Design for Maintaining Maritime Superiority, Version 2.0, December 2018, 
pp. 8, 10. 
14 Then-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.) 
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teams/swarms), team with individual manned combatants or augment battle groups.”15 The Navy 
states in its FY2020 budget submission that a Navy research and development effort focusing on 
concept generation and concept development (CG/CD) will 
Continue CG/CD development efforts that carry-over from FY[20]19: Additional concepts 
and  CONOPs  [concepts  of  operation]  to  be  developed  in  FY[20]20  will  be  determined 
through the CG/CD development process and additional external factors. Concepts under 
consideration include Unmanned Systems in support of DMO, Command and Control in 
support of DMO, Offensive Mine Warfare, Targeting in support of DMO, and Advanced 
Autonomous/Semi-autonomous Sustainment Systems.16 
The Navy also states in its FY2020 budget submission that a separate Navy research and 
development effort for fleet experimentation activities will include activities that “address key 
DMO concept action plan items such as the examination of Fleet Command and Maritime 
Operation Center (MOC) capabilities and the employment of unmanned systems in support of 
DMO.”17 
Highlighted in FY2020 Navy Budget 
In submitting its proposed FY2020 budget to Congress, the Navy highlighted its desire to develop 
and procure UVs of various types. Figure 4, for example, shows a table that the Navy included in 
its FY2020 budget highlights book summarizing proposed annual procurement quantities of 
selected USVs and UUVs over the five-year period FY2020-FY2024. In discussing the table, the 
budget highlights book states that 
The  FY  2020  budget  requests  $447  million  to  accelerate  the  unmanned  surface 
vehicle/vessel (USV) portion of the Navy’s Future Surface Combatant (FSC) strategy. The 
increase in funding from FY 2019 to FY 2020 includes $24 million for medium and $373 
million  for  large  USVs,  leading  to  the  transition  of  USV  prototypes  and  associated 
payloads from RDT&E to procurement beginning in FY 2021…. 
In  FY  2020  the  Navy  will  invest  $359  million  towards  unmanned  undersea  vehicles 
(UUV). The increase in funding from FY 2019 to FY 2020 includes $182 million for the 
development,  fabrication,  and  testing  of  the  ORCA  Extra  Large  Unmanned  Undersea 
Vehicles  and  $68  million  to  support  the  advancement  of  Large  Diameter  Unmanned 
Undersea  Vehicles.  The  FY  2020  funding  request  also  supports  small  and  medium 
unmanned undersea vehicles and MK-18 UUVs, as well as the associated payloads.18 
                                                 
15 Department of Defense, Fiscal Year (FY) 2020 Budget Estimates, Navy Justification Book Volume 2 of 5, Research, 
Development, Test & Evaluation, Navy, Budget Activity 4, March 2019, p. 202. 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 Maritime Operations and Unmanned Systems Tactical 
Employment, Naval Postgraduate School, June 2018, 171 pp. (Systems Engineering Capstone Report); Lyla Englehorn, 
Distributed Maritime Operations (DMO) Warfare Innovation Continuum (WIC) Workshop September 2017 After 
Action Report, Naval Postgraduate School, December 2017, 99 pp. 
16 Department of Defense, Fiscal Year (FY) 2020 Budget Estimates, Navy Justification Book Volume 2 of 5, Research, 
Development, Test & Evaluation, Navy, Budget Activity 4, March 2019, p. 1385. See also pp. 1382, 1384, 1443, 1445. 
17 Department of Defense, Fiscal Year (FY) 2020 Budget Estimates, Navy Justification Book Volume 4 of 5, Research, 
Development, Test & Evaluation, Navy Budget Activity 6, March 2019, p. 290. 
18 Department of the Navy, Highlights of the Department of the Navy FY 2020 Budget, p. 5-3. 
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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. Under these accelerated acquisition strategies, the Navy wants to 
procure LUSVs and XLUUVs at the same time that it is developing the enabling technologies and 
concepts of operations for these UVs.19 
As a reflection of its accelerated acquisition strategies, the Navy, as indicated in Figure 4, is 
proposing to fund the procurement of LUSVs and XLUUVs in FY2020-FY2024 through the 
Navy’s research and development account (known formally as the Research, Development, Test 
and Evaluation, Navy, or RDT&EN, account) rather than through one of the Navy’s procurement 
accounts. More specifically, the Navy in its FY2020 budget submission is proposing to fund the 
LUSV and MUSV programs and their enabling technologies in the RDT&EN account through 
projects within Program Element (PE) 0603502N,20 which is entitled Surface and Shallow Water 
MCM (mine countermeasures), and the XLUUV program through a project called Advanced 
Undersea Prototyping—Vehicles, Propulsion, and Navigation that is within PE 0604536N, which 
is entitled Advanced Undersea Prototyping. 
Figure 4. Proposed USV and UUV Annual Procurement Quantities 
 
Source: Department of the Navy, Highlights of the Department of the Navy FY 2020 Budget, Figure 5.2 on page 5-
3. 
Regarding its accelerated acquisition strategies for large UVs, the Navy states: 
While unmanned surface vehicles are new additions to fleet units, MUSV and LUSV are 
intended to be relatively low developmental technologies that combine robust and proven 
                                                 
19 Under a more traditional acquisition strategy, the enabling technologies and concepts of operation would be 
developed more fully before starting procurement, so as to reduce the amount of overlap, or concurrency, between 
development and procurement. Reducing development-procurement concurrency is generally considered preferable or 
an acquisition best practice if time allows, because it generally reduces technical risk in a program, but it might not be 
practical for meeting an urgent operational need. The risks of development-procurement concurrency in a program can 
be mitigated by taking steps such as using existing platform designs, using existing weapons and other systems, 
employing modularity in design so that weapons and systems can be easily installed onto or removed from the 
platform, and having technological fallback options that be used if initially selected technical approaches are not 
successful. 
20 Line items in DOD research and development accounts are called program elements, or PEs. 
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commercial vessel designs with existing military payloads to rapidly and affordably expand 
the  capacity  and  capability  of  the  surface  fleet.  Both  programs  benefit  from  years  of 
investment  and  full  scale  demonstration  efforts  in  autonomy,  endurance,  command  and 
control,  payloads  and  testing  from  the  Defense  Advanced  Research  Projects  Agency 
(DARPA)  Anti-Submarine  Warfare  Continuous  Trail  Unmanned  Vessel  (ACTUV)  and 
Office  of  Naval  Research  (ONR)  Medium  Displacement  Unmanned  Surface  Vehicle 
(MDUSV)/Sea  Hunter  (FY  2017  to  FY  2021)  and  Office  of  the  Secretary  of  Defense 
Strategic  Capabilities  Office  (OSD  SCO)  Ghost  Fleet  Overlord  Large  USV 
experimentation effort (FY 2018 to FY 2021). The combination of fleet-ready C2 solutions 
developed by the Ghost Fleet Overlord program and initial man-in-the-loop or man-on-the-
loop control will reduce the risk of fleet integration of unmanned surface vehicles and allow 
autonomy  and  payload  technologies  to  develop  in  parallel  with  fielding  vehicles  with 
standardized  interfaces.  Fleet  learning  with  early  MUSV  and  LUSV  units  plus  future 
upgrades of more advanced autonomy technology will allow eventual deployment as fully 
autonomous vehicles.21 
As shown in Figure 5, the Navy has identified five key enabling groups of technologies for its 
USV and UUV programs.22 Given limitations on underwater communications (most radio-
frequency electromagnetic waves do not travel far underwater), technologies for autonomous 
operations (such as artificial intelligence) will be particularly important for the XLUUV program 
(and other UUV programs).23 
In May 2019, the Navy established a surface development squadron to help develop operational 
concepts for LUSVs and MUSVs. The squadron will initially consist of a Zumwalt (DDG-1000) 
class destroyer and one Sea Hunter medium displacement USV. A second Sea Hunter will 
reportedly be added around the end of FY2020, and LUSVs and MUSVs will then be added as 
they become available.24 
The emphasis on UV programs in the Navy’s FY2020 budget submission and the Navy’s desire 
to employ accelerated acquisition strategies in acquiring large UVs together 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.25 
                                                 
21 Department of Defense, Fiscal Year (FY) 2020 Budget Estimates, Navy Justification Book Volume 2 of 5, Research, 
Development, Test & Evaluation, Navy, Budget Activity 4, March 2019, p. 202. For a press report that provides 
additional discussion, see, for example, Megan Eckstein, “Navy Planning Aggressive Unmanned Ship Prototyping, 
Acquisition Effort,” USNI News, May 15, 2019; Paul McCleary, “232 Unmanned Ships May Be Key To Countering 
China, Russia,” Breaking Defense, April 15, 2019. 
22 For additional discussion of some of the enabling technologies shown in Figure 5, see Pete Small, “Empowering the 
Unmanned Maritime Revolution,” Undersea Warfare, Spring 2019: 12-13. 
23 For more on the use of artificial intelligence in defense programs, see CRS Report R45178, Artificial Intelligence 
and National Security, by Kelley M. Sayler. 
24 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. 
25 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. 
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Large Navy USV and UUV Programs in Brief 
Large Unmanned Surface Vehicle (LUSV)26 
The LUSV program is a proposed new start project for FY2020. As shown in Figure 4, the Navy 
wants to procure two LUSVs per year in FY2020-FY2024.  
Figure 5. Enabling Technologies for USVs and UUVs 
 
Source: Slide 4 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. 
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.27 The Navy wants LUSVs to be capable of operating with human operators 
                                                 
26 Unless otherwise indicated, information in this section is taken from Department of Defense, Fiscal Year (FY) 2020 
Budget Estimates, Navy Justification Book Volume 2 of 5, Research, Development, Test & Evaluation, Navy, Budget 
Activity 4, March 2019, pp. 202, 230-231, and 233. 
27 In addition to the general source cited in footnote 26, the Navy states elsewhere 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, 
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in the loop,28 or semi-autonomously (with human operators on the loop),29 or fully autonomously, 
and to be capable of operating either independently or in conjunction with manned surface 
combatants. Although referred to as unmanned vehicles, LUSVs might be more accurately 
described as optionally 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.30 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. 
To have the desired payload capacity and endurance, the Navy believes, as indicated in Figure 1, 
that LUSVs generally will need to be greater than 50 meters (about 164 feet) in length. More 
specifically, the Navy envisions the LUSVs it wants to procure in FY2020-FY2024 as being 200 
feet to 300 feet in length and having a full load displacement of about 2,000 tons,31 which would 
make them the size of a corvette.32 In unclassified presentations on the program, the Navy has 
used images of offshore support ships used by the oil and gas industry to illustrate the kinds of 
ships that might be used as the basis for LUSVs.33 
The Navy’s FY2019 budget submission had projected procuring the first LUSV in FY2023, but 
the Navy’s FY2020 budget submission proposes accelerating the procurement of the first LUSVs 
to FY2020. To implement this accelerated acquisition timeline, the LUSV program will build 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 called Ghost Fleet, and its LUSV 
development effort within Ghost Fleet is called Overlord. The Navy states that SCO’s Overlord 
project 
converts  existing  commercial  fast  supply  vessels  into  experimentation  LUSVs,  with  the 
end  goal  to  demonstrate  relevant  Navy  Surface  Warfare  missions  utilizing  modular 
prototype  payloads.  The  Overlord  systems  will  also  advance  the  technology  needed  for 
autonomous  operation  of  pier-launched  vessels  as  well  as  increase  the  reliability  and 
redundancy required to support an unmanned Hull, Mechanical, and Electrical (HM&E) 
                                                 
accessed May 22, 2019, at https://www.navsea.navy.mil/Portals/103/Documents/Exhibits/SNA2019/
UnmannedMaritimeSys-Small.pdf?ver=2019-01-15-165105-297, and footnote 1 to the table shown in Figure 4.) 
28 The 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.) 
29 The 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.) 
30 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. 
31 See, for example, Joseph Trevithick, “Navy’s Budget Requests Two Huge Missile-Laden Drone Ships That Displace 
2,000 Tons,” The Drive, March 12, 2019; Sam LaGrone, “Navy Wants 10-Ship Unmanned ‘Ghost Fleet’ to 
Supplement Manned Force,” USNI News, March 13, 2019; Rich Abott, “Navy Pushing 10 Unmanned Ships Over Five 
Years,” Defense Daily, March 14 2019; David B. Larter, “A classified Pentagon Maritime Drone Program Is About to 
Get Its Moment in the Sun,” Defense News, March 14, 2019; Paul McCleary, “232 Unmanned Ships May Be Key To 
Countering China, Russia,” Breaking Defense, April 15, 2019. 
32 A corvette (also known as a light frigate) is a surface combatant that is larger than a patrol craft and smaller than a 
frigate. The Navy’s Cyclone (PC-1) class patrol craft have a length of 179 feet (about 54.6 meters), and the Navy’s 
most recent frigates—the Oliver Hazard Perry (FFG-7) class ships, the last of which was retired in 2015—had a length 
of 455.25 feet (about 188.8 meters) in their final configuration. 
33 Sam LaGrone, “Navy Wants 10-Ship Unmanned ‘Ghost Fleet’ to Supplement Manned Force,” USNI News, March 
13, 2019. 
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system. The Overlord systems will be able to travel thousands of miles between port visits, 
as well as operate for weeks at a time…. 
The Navy is able to rapidly initiate the  LUSV program in  FY 2020 as a direct result of 
transitioning  the  OSD  SCO  Ghost  Fleet  Overlord  technology.  In  addition  to  the  two 
experimentation LUSVs procured in FY 2019 by the Ghost Fleet Program, the Navy will 
procure two FY 2020 experimentation LUSVs of the same configuration (from the same 
vendors on the same contracts) as the Ghost Fleet Overlord systems and modular payloads 
will be procured to fully populate the 4 Overlord (2 SCO funded in FY 2019 and 2 Navy 
funded  in  FY  2020)  experimentation  LUSVs.  While  the  Overlord  configuration  rapidly 
delivers  an  initial  LUSV  capability,  it  does  not  provide  the  integrated  and  organic 
capability  or  capacity  intended  for  the  LUSV  program.  The  Navy  intends  to  begin 
procuring [additional] LUSVs [employing a follow-on configuration] at a rate of 2 per year 
starting in FY 2021. Design contracts will be competitively awarded in FY 2020 to develop 
an  LUSV  with  an  integrated  (GFE)  [government-furnished  equipment]  launcher  system 
and  capacity  for  additional  modular  payloads.  LUSVs  of  this  [follow-on]  configuration 
will  be  procured  starting  in  FY  2021  with  competitive  detail  design  and  construction 
contract(s). Payloads will be procured separately.34 
The Navy issued a Request for Information (RFI) for the LUSV program on March 13, 2019, 
with responses due by April 26, 2019.35 The Navy plans to release a Request for Proposals (RFP) 
for concept design contracts for the LUSV program in FY2019, and to award multiple concept 
design contracts for the program in FY2020. The Navy plans to use the concept designs to inform 
the RFP that the Navy plans to release in FY2020 for the detailed design and construction 
(DD&C) contract for the LUSV with the follow-on configuration. The Navy plans to award in 
FY2021 a DD&C contract for initial LUSVs employing the follow-on configuration to one or 
more vendors. 
Although the Navy is proposing under its FY2020 budget submission to fund the acquisition of 
LUSVs through FY2024 under the Navy’s research and development account, the Navy may 
decide in a future budget submission to modify this plan so that funding for acquiring LUSVs 
shifts to the Navy’s shipbuilding account prior to FY2024. 
Medium Unmanned Surface Vehicle (MUSV)36 
The MUSV program began in FY2019. Although it is not shown in Figure 4, the Navy plans to 
award a contract for the first MUSV in FY2019 and wants to award a contract for the second 
MUSV in FY2023. 
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 
states that MUSVs “will be designed to be attritable assets [i.e., assets that can be lost in battle] if 
used in a peer or near-peer conflict.”37 The Navy wants MUSVs to be capable initially of 
                                                 
34 Department of Defense, Fiscal Year (FY) 2020 Budget Estimates, Navy Justification Book Volume 2 of 5, Research, 
Development, Test & Evaluation, Navy, Budget Activity 4, March 2019, p. 230. 
35 See, for example, Rich Abott, “Navy Issues RFI For LUSV, Using Ghose Fleet Overlord Program,” Defense Daily, 
March 15, 2019. 
36 Unless otherwise indicated, information in this section is taken from Department of Defense, Fiscal Year (FY) 2020 
Budget Estimates, Navy Justification Book Volume 2 of 5, Research, Development, Test & Evaluation, Navy, Budget 
Activity 4, March 2019, pp. 202, 258-259, and 261. 
37 Department of Defense, Fiscal Year (FY) 2020 Budget Estimates, Navy Justification Book Volume 2 of 5, Research, 
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operating with human operators in the loop, or semi-autonomously, with human operators on the 
loop. 
As shown in Figure 1, the Navy defines MUSVs as having a length of between 12 meters (about 
39 feet) and 50 meters (about 164 feet). Some Navy surface ships are equipped to embark, 
launch, and recover boats or USVs with lengths of up to 11 meters (about 36 feet). The minimum 
length of 12 meters is thus an indication that MUSVs will be too large to be deployed from these 
manned Navy surface ships, and will instead more likely be launched from pier. 
The Navy wants to pursue the MUSV program as a rapid prototyping effort under what is known 
as Section 804 acquisition authority.38 To help implement this rapid prototyping effort, the MUSV 
program will build 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 (Figure 6), which has a reported length of 132 feet (about 40.2 
meters) and a displacement of about 140 tons.39 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 in its FY2020 budget submission that 
A  development  RFP  [for  MUSV]  will  be  released  to  industry  in  FY  2019,  containing 
options for additional USVs contingent on validation of warfighting requirements. A full 
and open procurement will take place in FY 2019, awarding a single MUSV prototype at 
the end of FY 2019…. The requirements of the  MUSV will allow proposals from both 
traditional defense and commercial shipyards. Estimated delivery of the initial prototype 
will be FY 2022.40 
Extra Large Unmanned Undersea Vehicle (XLUUV)41 
The XLUUV program, also known as Orca, 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 
                                                 
Development, Test & Evaluation, Navy, Budget Activity 4, March 2019, p. 258. 
38 This is a reference to Section 804 of the FY2016 National Defense Authorization Act (S. 1356/P.L. 114-92 of 
November 25, 2015). The rapid prototyping authority provided by that section is now codified at 10 U.S.C. 2302 note. 
For more on this authority, see “Middle Tier Acquisition (Section 804),” MITRE, undated, accessed May 24, 2019, at 
https://aida.mitre.org/middle-tier/; and “Acquisition Process, Middle Tier Acquisition (Section 804),” AcqNotes, 
updated March 26, 2019, accessed May 24, 2019, at http://acqnotes.com/acqnote/acquisitions/middle-tier-acquisitions. 
39 See, for example, Megan Eckstein, “Sea Hunter Unmanned Ship Continues Autonomy Testing as NAVSEA Moves 
Forward with Draft RFP,” USNI News, April 29, 2019; Evan Milberg, “DARPA “Sea Hunter,” World’s Largest 
Autonomous Ship, Transferred to U.S. Navy,” Composites 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. 
40 Department of Defense, Fiscal Year (FY) 2020 Budget Estimates, Navy Justification Book Volume 2 of 5, Research, 
Development, Test & Evaluation, Navy Budget Activity 4, March 2019, p. 261. 
41 Unless indicated otherwise, information in this section is taken from Department of Defense, Fiscal Year (FY) 2020 
Budget Estimates, Navy Justification Book Volume 2 of 5, Research, Development, Test & Evaluation, Navy Budget 
Activity 4, March 2019, pp. 1289, 1298, and 1300. 
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Navy Large Unmanned Surface and Undersea Vehicles:  
 
manned Navy submarine.42 Consequently, XLUUVs instead will more likely be launched from 
pier. The Navy wants XLUUVs to be equipped with a modular payload bay. 
Figure 6. Sea Hunter 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. 
As shown in Figure 4, the Navy wants to procure nine XLUUVs in FY2020-FY2024. 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.43 (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.44 The 
Navy is reserving the right to conduct a new competition for the contract to build the four 
XLUUVs that the Navy wants to procure in FY2023 and FY2024.45 
Boeing’s Orca XLUUV design will be informed by (but will likely differ in certain respects from) 
the design of Boeing’s Echo Voyager UUV, 46 which is shown in Figure 7, Figure 8, and Figure 
9. 
                                                 
42 Navy submarines equipped with large-diameter vertical launch tubes can launch missiles or other payloads with 
diameters of up to about 83 inches. 
43 Department of Defense, Contracts for Feb. 13, 2019. 
44 Department of Defense, Contracts for March 27, 2019. 
45 See, for example, Justin Katz, “Additional XLUUVs in Navy Budget Request Not Guaranteed to Boeing,” Inside 
Defense, April 18, 2019. 
46 See, for example, Hugh Lessig, “Shipbuilder Lends a Hand with Rise of Robot Submarines,” Defense News, May 26, 
2019. 
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Figure 7. Boeing Echo Voyager UUV 
 
Source: Boeing photograph posted at https://www.boeing.com/defense/autonomous-systems/echo-voyager/
index.page#/gallery. 
Figure 8. Boeing Echo Voyager UUV 
 
Source: Boeing photograph posted at https://www.boeing.com/defense/autonomous-systems/echo-voyager/
index.page#/gallery. 
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Figure 9. Boeing Echo Voyager UUV 
 
Source: Photograph accompanying “Boeing Echo Voyager Takes the Plunge,” Hydrographic Catalogue, posted 
by Boeing on June 26, 2017. 
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 about 900 cubic feet. Echo Voyager can also accommodate external 
payloads.47 
Boeing has partnered with the Technical Solutions division of Huntington Ingalls Industries (HII) 
to build Orca XLUUVs.48 A separate division of HII—Newport News Shipbuilding (NNS) of 
Newport News, VA—is one of the Navy’s two submarine builders. 
FY2020-FY2024 Funding 
Table 1 shows FY2020-FY2024 requested and programmed funding for the large UV programs 
covered in this report. As shown in the table, the Navy is requesting $628.8 million in FY2020 
research and development funding for the LUSV, MUSV, and XLUUV programs and LUSV and 
MUSV enabling technologies, and the Navy’s FY2020 budget submission programs a total of 
$4,518.8 million for the programs and their enabling technologies during the period FY2020-
FY2024. 
                                                 
47 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. 
48 See, for example, Hugh Lessig, “Shipbuilder Lends a Hand with Rise of Robot Submarines,” Defense News, May 26, 
2019. 
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Table 1. FY2020-FY2024 Requested and Programmed Funding for Large UVs 
Millions of dollars, rounded to nearest tenth 
FY20-
FY24 
Program 
FY20 
FY21 
FY22 
FY23 
FY24 
total 
LUSV 
372.5 
535.4 
584.3 
607.6 
638.0 
2,737.8 
MUSV 
23.9 
26.3 
30.0 
43.0 
43.86 
167.1 
LUSV and MUSV enabling technologies 
50.4 
199.3 
177.3 
247.5 
132.0 
806.5 
XLUUV 
182.0 
126.1 
33.5 
229.9 
236.0 
807.4 
TOTAL 
628.8 
887.0 
825.1 
1,128.0 
1,049.9 
4,518.8 
Source: Navy FY2020 budget submission. LUSV is Project 3066 within PE (Program Element) 0603502N (line 34 
in the Navy’s FY2020 research and development account). MUSV is Project 3428 within PE 0603502N (line 34). 
LUSV and MUSV enabling technologies is Project 3067 within PE 0603502N (line 34). XLUUV is Project 3394 
within PE 0604536N (line 87). 
Notes: 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: 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 well developed, and how well tested, are the operational concepts 
associated with the more-distributed architecture? 
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: Are these accelerated acquisition strategies appropriate for these programs? 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, and 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?49 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? 
                                                 
49 For more on this shift, see CRS Report R43838, A Shift in the International Security Environment: Potential 
Implications for Defense—Issues for Congress, by Ronald O'Rourke. 
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Navy Large Unmanned Surface and Undersea Vehicles:  
 
Additional potential oversight questions for Congress include: Is it appropriate for these large 
UVs to be procured in FY2020 and subsequent years with research and development funding 
rather than procurement funding? What implications might the Navy’s proposed funding 
approach have for visibility to Congress of the costs of these programs? In what ways does 
funding the acquisition of these large UVs with research and development funding rather than 
procurement funding support the accelerated acquisition strategies being proposed for these 
programs? 
Technical, Schedule, and Cost Risk 
Another potential oversight issue for Congress concerns the amount of technical, schedule, and 
cost risk in these programs. Potential oversight questions for Congress include: How much risk of 
this kind do these programs pose, particularly given the enabling technologies that need to be 
developed for them? 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, and 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? 
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 FY2020-FY2024. Potential oversight 
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: 
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 small 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? 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? When funding for the procurement of 
LUSVs (or other large UVs) shifts from the Navy’s research and development account to the 
Navy’s shipbuilding account, what impact, if any, might that have on funding available in the 
Navy’s shipbuilding account for procuring manned ships? 
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: What implications might these large UVs have for the required 
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skills, training, and career paths of Navy personnel? Within the Navy, what will be the 
relationship between personnel who crew manned ships and those who operate these large UVs? 
FY2020 Funding 
Another oversight issue for Congress concerns the funding amounts for these programs that the 
Navy has requested for these programs for FY2020. Potential oversight questions for Congress 
include: Has the Navy accurately priced the work on these programs that it is proposing to do in 
FY2020? 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 FY2020? 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 FY2020 
Summary of Congressional Action on FY2020 Funding Request 
Table 2 summarizes congressional action on the Navy’s FY2020 funding request for the LUSV, 
MUSV, and XLUUV programs and their enabling technologies. 
Table 2. Congressional Action on FY2020 Large UV Funding Request 
Millions of dollars, rounded to the nearest tenth 
 
 
Authorization 
Appropriation 
 
Request 
HASC 
SASC 
Conf. 
HAC 
SAC 
Conf. 
LUSV 
372.5 
134.7 
0 
 
176.9 
 
 
MUSV 
23.9 
66.9 
23.9 
 
23.9 
 
 
LUSV and LUSV 
50.4 
50.4 
50.4 
 
50.4 
 
 
enabling technologies 
XLUUV 
182.0 
174.4 
182.0 
 
164.4 
 
 
Source: Table prepared by CRS based on FY2020 Navy budget submission, committee and conference reports, 
and explanatory statements on the FY2020 National Defense Authorization Act and the FY2020 DOD 
Appropriations Act. 
Notes: LUSV is Project 3066 within PE (Program Element) 0603502N (line 34 in the Navy’s FY2020 research 
and development account). MUSV is Project 3428 within PE 0603502N (line 34). LUSV and MUSV enabling 
technologies is Project 3067 within PE 0603502N (line 34). XLUUV is Project 3394 within PE 0604536N (line 
87). 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. 
FY2020 National Defense Authorization Act (H.R. 2500/S. 1790) 
House 
The House Armed Services Committee, in its report (H.Rept. 116-120 of June 19, 2019) on H.R. 
2500, recommended the funding levels shown in the HASC column of Table 2. The 
recommended reduction of $237.8 million for LUSV includes reductions of $29.1 million for 
“LUSV Design Contracts early to need,” $79.2 million for “LUSV GFE [government-furnished 
equipment] early to need,” $43.0 million for “LUSV program decrease,” and $86.5 million for 
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“Reduce one LUSV.” The recommended increase of $43.0 million for MUSV is for “MUSV 
program increase.” (Page 427) The recommended reduction of $7.53 million for XLUUV is for 
“ORCA XLUUV prior year carryover.” (Page 429) 
Senate 
The Senate Armed Services Committee, in its report (S.Rept. 116-48 of June 11, 2019) on S. 
1790, recommended the funding levels shown in the SASC column of Table 2. Regarding the 
recommended reduction of $372.5 million (the entire requested amount) for LUSV, S.Rept. 116-
48 states: 
Large unmanned surface vessels 
The budget request included $20.3 billion in Research, Development, Test, and Evaluation 
(RDT&E), Navy, of which $507.0 million was for PE 63502N Surface and Shallow Water 
Mine Countermeasures.  
The  committee  notes  that  the  budget  request  for  this  program  element  provides  for  the 
prototyping  and  testing  of  Large  Unmanned  Surface  Vessels  (LUSV),  including 
procurement of two additional LUSVs in conjunction with a Strategic Capabilities Office 
(SCO) initiative, in project 3066. The committee understands that the two LUSVs procured 
by the SCO beginning in fiscal year 2018, at a cost of $237 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 is 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  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. 
Accordingly, the committee recommends a decrease of $372.5 million, for a total of $134.5 
million, in RDT&E, Navy, for PE 63502N. (Page 80) 
S.Rept. 116-48 also states: 
Acquisition roadmaps for certain Navy unmanned systems 
The committee notes that the Navy's fiscal year 2020 future years defense program (FYDP) 
includes  a  substantial  increase  in  funding  for  various  unmanned  systems,  including 
unmanned  surface  vessels  (USVs)  and  unmanned  underwater  vessels  (UUVs).  The 
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committee  further  notes  that  Navy  leaders  envision  some  of  these  systems'  operating 
autonomously with the ability to employ weapons. 
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  report  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. 
Each roadmap shall: (1) Identify the applicable requirements document (e.g., Top 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. (Pages 106-107) 
FY2020 DOD Appropriations Act (H.R. 2968) 
House 
The House Appropriations Committee, in its report (H.Rept. 116-84 of May 23, 2019) on H.R. 
2968, recommended the funding levels shown in the HAC column of Table 2. 
The recommended reduction of $195.92 million for the LUSV program includes a reduction of 
$96.42 million for “limit to one LUSV,” a reduction of $79.2 million for “long lead material early 
to need,” and a reduction of $20.0 million for “excess design support.” (Page 254) 
The recommended reduction of $17.53 million for the XLUUV program includes a reduction of 
$10.0 million for “Testing early to need” and a reduction of $7.53 million for “Dual-vendor 
award acquisition strategy.” (Page 256) 
H.Rept. 116-84 states: 
RESEARCH  AND  WORKFORCE  PARTNERSHIPS  FOR  SUBMARINE  AND 
UNDERSEA VEHICLE PROGRAMS 
The Committee recognizes the need for greater partnerships between Navy research labs, 
academia, and industry. The Committee encourages the Secretary of the Navy to coordinate 
efforts with its industrial base partners to ensure that funded research projects are relevant 
to specific engineering and manufacturing needs, as well as defined systems capabilities. 
Partnerships  with  academia  should  focus  on  specific,  well-defined  short-  and  long-term 
submarine  and  autonomous  undersea  vehicle  research  needs,  accelerated  technology 
transition,  and  should  also  include  a  strong  workforce  development  component  to  help 
ensure a sustainable industrial base. (Page 264)
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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 3 · UPDATED 
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