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

Summary: The Navy in FY2021 and beyond wants to develop and procure three types of large unmanned 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 is requesting $579.9 million in FY2021 research and development funding for these large UVs and their enabling technologies.

Summary: 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.

Summary: 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.

Summary: 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 payloadsâparticularly 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 concepts. 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 these large UVs, particularly the LUSV. In response, the Navy's FY2021 budget submission proposes to modify 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 is proposing to use 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.

Summary: 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.

Summary: 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 does not include funding for the procurement of additional XLUUVs in FY2021 or FY2022.

Summary: 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 in FY2021 on the programs.

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 is requesting $579.9 million 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 FY2021 funding requests for these large UVs. The Navy's proposals for developing and procuring them pose a number of oversight issues for Congress. Congress's decisions on these issues could substantially affect Navy capabilities and funding requirements and the shipbuilding and UV industrial bases.

In addition to the large UVs covered in this report, the Navy also wants to develop and procure smaller USVs and UUVs, as well as unmanned aerial vehicles (UAVs) of various sizes. Other U.S. military services are developing, procuring, and operating their own types of UVs. Separate CRS reports address some of these efforts.

UVs are one of several new capabilitiesâalong with directed-energy weapons, hypersonic weapons, artificial intelligence, and cyber capabilitiesâthat the Navy says it is pursuing to meet emerging military challenges, particularly from China. UVs can be equipped with sensors, weapons, or other payloads, and can be operated remotely, semi-autonomously, or (with technological advancements) autonomously. They can be individually less expensive to procure than manned ships and aircraft because their designs do not need to incorporate spaces and support equipment for onboard human operators. UVs can be 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."

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 will include 45 UVs, and that its projected inventory of 4,075 aircraft at the end of FY2021 will include 57 UVs. 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.

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.

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.

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, 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.

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 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."

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, and a platform ratio of 2-1-0-0) 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, and a platform ration of 1-2-3-4) 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 architectureâwhich concentrates much of the fleet's capability into a relatively limited number of individually larger and more expensive surface shipsâis 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. 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.

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 have shifted their thinking, with comments from Navy officials like the one quoted above and Navy briefing slides like Figure 3 indicating 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 neededâas the observers have long arguedâto 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 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). 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." While Navy officials have provided few details in public about DMO, 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."

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 challenges from countries such as China.

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 called Ghost Fleet, and its LUSV development effort within Ghost Fleet is called Overlord.

As shown in Figure 4 , the Navy has identified five key enabling groups of technologies for its USV and UUV programs. 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).

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 prototype medium displacement USV ( Figure 5 ). A second Sea Hunter prototype will reportedly be added around the end of FY2020, and LUSVs and MUSVs will then be added as they become available.

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 6 shows a detail from a Navy briefing slide showing images of prototype LUSVs and silhouettes of a notional LUSV and a notional MUSV. 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.

The Navy wants LUSVs to be low-cost, high-endurance, reconfigurable ships based on commercial ship designs, with ample capacity for carrying various modular payloadsâparticularly anti-surface warfare (ASuW) and strike payloads, meaning principally anti-ship and land-attack missiles.

The Navy wants LUSVs to be capable of operating with human operators in the loop, or semi-autonomously (with human operators on the loop), 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 optionally or lightly manned ships, because they might sometimes have a few onboard crew members, particularly in the nearer term as the Navy works out LUSV enabling technologies and operational concepts. 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.

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 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.

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.

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.

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 adjustments, 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)

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.

In response to the markups from the congressional defense committees, the Navy's FY2021 budget submission proposes to modify 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 is proposing to use 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.

A January 13, 2020, press report stated that the Navy plans to submit a report on the Navy's concepts of operations for LUSVs and MUSVs in April 2020.

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 middle tier acquisition authority. 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. 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 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. Consequently, XLUUVs instead will transported to a forward operating port and then launched from pier. The Navy wants XLUUVs to be equipped with a modular payload bay for carrying mines and other payloads.

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. (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. Boeing has partnered with the Technical Solutions division of Huntington Ingalls Industries (HII) to build Orca XLUUVs. (A separate division of HIIâNewport News Shipbuilding (NNS) of Newport News, VAâis 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.

Boeing's Orca XLUUV design will be informed by (but likely differ in certain respects from) the design of Boeing's Echo Voyager UUV ( Figure 7 , Figure 8 , and Figure 9 ). 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.

Table 1 shows FY2021-FY2025 requested and programmed funding for the large UV programs covered in this report.

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 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 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? 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?

Another potential oversight issue for Congress concerns the amount of technical, schedule, and cost risk in these programs. 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?

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 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?

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 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?

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 targetsâand 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 Gulfânot least the South China Sea, where the U.S. has recently confronted both China and Russiaâ¦.

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 glider in the sea approximately 100 kilometers off the Philippines in December 2016. The winged, torpedo-shaped unit was within sight of its handlers aboard the U.S. Navy oceanographic vessel Bowditch, who gaped in astonishment as it was summarily hoisted aboard a Chinese warship less than a kilometer distant. The U.S. responded with a diplomatic demarche and congressional opprobrium, and the glider was returned within the weekâ¦.

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 deployedâ¦.

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 vehiclesâ¦.

Nearly 100,000 ships transit the strategically vital Singapore Strait annually, where more than 75 collisions or groundings occurred last year alone. In such congested international sea lanes, declaring a foreign navy's autonomous vessel wayward or unresponsive would easily serve as convenient rationale for towing it into territorial waters for impoundment, or for boarding it straightawayâ¦.

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.

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 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?

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?

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.


FY2020 National Defense Authorization Act: P.L. 116-92 (H.R. 2500, S. 1790)

Summary: The Administration's FY2020 NDAA request would have authorized $568.1 billion designated as base budget funds to cover the routine, recurring costs to man, train, and operate U.S. forces. The request would have authorized an additional $173.8 billion designated as Overseas Contingency Operations (OCO) funds, of which $97.9 billion was requested for base programs. As enacted, the FY2020 NDAA authorizes a total of $729.9 billion for national defense-related activities, which is $12.0 billion (1.6%) less than the Administration requested.

This report provides an overview of the FY2020 National Defense Authorization Act ( H.R. 2500 , S. 1790 , P.L. 116-92 ) and serves as a portal to other CRS products providing additional context, detail, and analysis concerning particular aspects of that legislation.

Enacted annually to cover every defense budget since FY1962, the NDAA authorizes funding for the Department of Defense (DOD) activities at the same level of detail at which budget authority is provided by the corresponding defense, military construction, and other appropriations bills. While the NDAA does not provide budget authority, historically it has provided a fairly reliable indicator of congressional sentiment on funding for particular programs. The bill also incorporates provisions of law governing military compensation, the DOD acquisition process, and aspects of DOD policy toward other countries, among other subjects.

Of the $761.8 billion requested by the Trump Administration for National Defense-related activities in FY2020, $750.0 billion is discretionary spending, of which approximately $741.9 billion falls within the scope of the annual NDAA. This includes $718.4 billion for DOD operations and $23.2 billion for defense-related work by the Energy Department involving nuclear energy, mostly related to nuclear weapons and nuclear power plants for warships. Other funding for defense-related activities, such as counter-intelligence work of the Federal Bureau of Investigation (FBI), falls mostly under the jurisdiction of other congressional committees. (See Figure 1 .)

The following overview reviews the strategic and budgetary context within which Congress debated the FY2020 NDAA. Subsequent sections of the report summarize the bill's treatment of major components of the Trump Administration's FY2020 budget request as well as provisions attached to the final bill that deal with other issues.

As enacted, the FY2020 NDAA authorizes a total of $729.9 billion for national defense-related activities, which is $12.0 billion (1.6%) less than the Administration requested. The request included $568.1 billion to be designated as base budget funds to cover the routine, recurring costs to man, train, and operate U.S. forces. The request also included an additional $173.8 billion to be designated as Overseas Contingency Operations (OCO) funds to cover costs associated with the aftermath of the terrorist attacks of September 11, 2001, and other activities.

OCO-designated funds are exempt from the binding caps on defense spending set by the Budget Control Act of 2011 ( P.L. 112-25 ) and the Administration's request included $97.7 billion to be designated as OCO funding but intended to pay base budget expenses. ( Table 1 .)

The Senate Armed Services Committee reported its version of the FY2020 NDAA ( S. 1790 , S.Rept. 116-48 ) on June 11, 2019 and the Senate passed the bill on June 27, 2019. The House Armed Services Committee (HASC) reported its version ( H.R. 2500 , H.Rept. 116-120 ) on June 19, 2019 and the House passed the bill on July 12, 2019.

On September 17, 2019, the House took up the Senate-passed S. 1790 , amended it by eliminating the Senate-passed provisions and replacing them with the provisions of the House-passed H.R. 2500 , and then passed the amended bill by voice vote. House and Senate conferees worked to produce a conference version of S. 1790 . The conference report ( H.Rept. 116-333 ) was agreed to by the House on December 11, 2019 by a vote of 377-48 and agreed to by the Senate on December 17, 2019 by a vote of 86-8. ( Table 2 .)

According to the Administration, the FY2020 budget request for DOD reflects a shift in strategic emphasis based on the 2018 National Defense Strategy (NDS), which called for "increased and sustained investment" to counter evolving threats from China and Russia. This would mark a change from the focus of U.S. national security policy for nearly the past three decades and a renewed emphasis on competition between nuclear-armed superpowers, which had been the cornerstone of U.S. strategy for more than four decades after the end of World War II.

During the Cold War, U.S. national security policy and the design of the U.S. military establishment were strategically focused on competing with the Union of Soviet Socialist Republics and containing the global spread of communism. In the years following the collapse of the Soviet Union, U.S. policies were designedâand U.S. forces were trained and equippedâlargely with a focus on dealing with potential regional aggressors such as Iraq, Iran, and North Korea and on recalibrating relations with China and Russia.

After the terrorist attacks of September 11, 2001, U.S. national security policy and DOD planning focused largely on countering terrorism and insurgencies in the Middle East while containing, if not reversing, North Korean and Iranian nuclear weapons programs. However, as a legacy of the Cold War, U.S. and allied military forces had overwhelming military superiority over these adversaries and, accordingly, operations were conducted in relatively permissive environments.

The 2014 Russian invasion of the Crimean peninsula and subsequent proxy war in eastern Ukraine fostered a renewed concern in the United States and Europe about an aggressive and revanchist regime in Moscow. Meanwhile, China began building and militarizing islands in the South China Sea in order to lay claim to key shipping lanes. Together, these events highlighted anew the salience in the U.S. national security agenda of dealing with other great powers , that is, states able and willing to use military force unilaterally to accomplish their objectives. At the same time, the challenges that had surfaced at the end of the Cold Warâfragile states, genocide, terrorism, and nuclear proliferation, to name a fewâremained serious threats to U.S. interests.

In some cases, adversaries appear to be collaborating to achieve shared or compatible objectives and to take advantage of social and economic tools to advance their agendas. Some states are also collaborating with non-state proxies (including, but not limited to, militias, criminal networks, corporations, and hackers) and deliberately blurring the lines between conventional and irregular conflict and between civilian and military activities. In this complex security environment, it is arguably more difficult than in past eras to manage these myriad problems.

The Trump Administration's December 2017 National Security Strategy (NSS), the 11-page unclassified summary of the January 2018 National Defense Strategy (NDS), and the 2019 National Intelligence Strategy explicitly reorient U.S. national security strategy (including defense strategy) toward a primary focus on great power competition with China and Russia and on countering their military capabilities.

In addition to explicitly making the great power competition the primary U.S. national security concern, the NDS also argues for a focus on bolstering the competitive advantage of U.S. forces, which, the document contends, has eroded in recent decades vis-Ã -vis the Chinese and Russian threats. The NDS also maintains that, contrary to what was the case for most of the years since the end of the Cold War, U.S. forces now must assume that their ability to approach military objectives will be vigorously contested.

The Trump Administration's strategic orientation as laid out in the NSS and NDA is consistent with the strategy outlined in comparable documents issued by prior Administrations, in identifying five significant external threats to U.S. interests: China, Russia, North Korea, Iran, and terrorist groups with global reach. In a break from previous Administrations, however, the NDS views retaining the U.S. strategic competitive edge relative to China and Russia as a higher priority than countering violent extremist organizations. Accordingly, the new orientation for U.S. strategy is sometimes referred to a " 2+3 " strategy, meaning a strategy for countering two primary challenges (China and Russia) and three additional challenges (North Korea, Iran, and terrorist groups).

In the four decades since the end of U.S. military involvement in Vietnam, annual outlays by the federal government have increased by a factor of nine. The fastest growing segment of federal spending during that period has been mandatory spending for entitlement programs such as Social Security, Medicare, and Medicaid. (See Figure 2 .)

The Budget Control Act (BCA) of 2011 (P.L. 112-25) was intended to reduce spending by $2.1 trillion over the period FY2012-FY2021, compared to projected spending over that period. One element of the act established binding annual limits (or caps) to reduce discretionary federal spending through FY2021 by $1.0 trillion. Separate annual caps on discretionary appropriations for defense-related activities and nondefense activities are enforced by a mechanism called sequestration .

Sequestration provides for the automatic cancellation of previous appropriations, to reduce discretionary spending to the BCA cap for the year in question. The caps on defense-related spending apply to discretionary funding for DOD and for defense-related activities of other agencies, comprising the national defense budget function which is designated budget function 050 .

Compliance with the BCA defense caps would have required DOD to reduce its planned spending by tens of billions of dollars per year through FY2021. Congress repeatedly has raised the annual spending caps to reduce their impact on projected spending. Nevertheless, the defense cap in effect when the Trump Administration submitted its FY2020 budget request was $576 billionâ$97.9 billion less than the Administration requested for base budget spending.

To avoid breaking that cap, the Administration designated as OCO funding a total of $97.9 billion to fund base budget activities. In marking up their respective versions of the FY2020 NDAA, the Armed Services Committees of the House and Senate each treated those funds as part of the base budget. The issue became moot after the defense spending cap was raised by the Bipartisan Budget Act of 2019 (P.L. 116-37), enacted on August 2, 2019.

The total FY2020 DOD requestâincluding both base budget and OCO fundingâcontinued an upswing that began with the FY2016 budget, which marked the end of a relatively steady decline in real (that is, inflation-adjusted) DOD purchasing power. Measured in constant dollars, DOD funding peaked in FY2010, after which the drawdown of U.S. troops in OCO operations drove a reduction in DOD spending. ( Figure 3 .)

The enacted version of the FY2020 NDAA â like the House and Senate versions of the bill -- approves the Administration's proposal for a relatively modest net increase in the number of active-duty military personnel. It also authorizes the Administration's proposed reduction in the end-strength of the Selected Reserveâthose members of the military reserve components and the National Guard who are organized into operational units that routinely drill, usually on a monthly basis. ( Ta b le 3 .)

Section 609 of the enacted FY2020 NDAA authorizes a 3.1% increase in military basic pay, as was requested by the Administration. It is the same increase that would have occurred if neither Congress nor the President had taken any action on the subject. By law, military personnel receive an annual increase in basic pay that is indexed to the annual increase in the Labor Department's Employment Cost Index (ECI) unless either (1) Congress passes a law to provide otherwise; or (2) the President specifies an alternative pay adjustment.

The initial Senate version of the NDAA was silent regarding the pay raise.

The initial House version of the bill would have:

Mandated a 3.1% raise (Section 606); and Authorized the same 3.1% raise, even if the President had specified a different increase (Section 607). This provision was not included in the final version of the bill.

Following the death of a servicemember, certain beneficiaries may be eligible for survivor benefits from both DOD (under the Survivors Benefit Program or SBP) and the Department of Veterans Affairs (under the Dependency and Indemnity Compensation or DIC). However, by law, surviving spouses who receive both annuities must have their SBP payments reduced by the amount of DIC they receive. Critics refer to this offset as aÂ  widows' tax .

Section 622 of the enacted version of the FY2020 NDAA phases out the DIC offset requirement over a period of three years. Section 630A of the initial House-passed version would have repealed the offset, outright. The initial Senate-passed version was silent on the issue.

A DOD policy adopted on April 12, 2019, prohibits entry into military service of any person who identifies as transgender. The policy allows transgender individuals to apply for a waiver of that prohibition.

The enacted version of the bill does not challenge the Administration's policy. However, Section 596 of the NDAA conference report requires DOD to report on the number of requested waivers to the transgender ban that have been denied. Section 596 of the House-passed version of the bill would have established a similar reporting requirement.

Section 530B of the House-passed version of the bill, which was not included in the conference report, would have nullified the transgender ban, extending to gender identity the same legal protection against discrimination that current law provides for race and sex.

The Senate version of the NDAA contained no provisions relevant to this issue.

Section 731 of the NDAA conference report authorizes the Secretary of Defense to pay a claim for the death or personal injury of a servicemember resulting from medical malpractice by a DOD health care provider. This addresses a legal doctrine rooted in the Supreme Court's 1950 ruling, in the case of Feres v. United States , that the federal government is immunized from liability "for injuries to servicemen where the injuries arise out of or are in the course of activity incident to service." Many lower federal courts have concluded that this principle, known as the Feres doctrine, generally prohibits military servicemembers from asserting malpractice claims against the United States based on the negligent actions of health care providers employed by the military.

Section 729 of the House version of the NDAA bill would have overturned the Feres doctrine by amending the Federal Tort Claims Act to allow servicemembers to pursue tort claims against the United States for medical malpractice committed by health care provider in a Military Treatment Facility (MTF).

The Senate bill had no provision covering this subject.

In general, the conference report on the FY2020 NDAA supported the Trump Administration's budget request for nuclear and other long-range strike weapons. This program continues an across the board modernization of the nuclear triad: ballistic missile-launching submarines, long-range bombers, and intercontinental ballistic missiles (ICBMs).

However, the Trump program also included proposals to diversify the arsenal of nuclear weapons that the triad might deliver. The conference report did not include provisions of the House version of the bill that would have limited some of those efforts.

The NDAA conference report authorizes $29.6 million requested to deploy on some Trident II submarine-launched missiles nuclear warheads with significantly less explosive power than those now in service. According to unclassified sources, each of the several W-76 warheads currently carried by a single Trident II currently has an explosive power (or yield) approximately equal to that of 100 thousand tons of TNT (100 kilotons). The intended yield of the new "low-yield" warhead is reported to be about 10 kilotons. The atomic weapons detonated at Hiroshima and Nagasaki were roughly 15 kilotons and 20 kilotons, respectively.

As requested, the enacted NDAA authorizes $10 million in the Energy Department's national security budget to modify existing warheads and $19.6 million to install them in deployed missiles.

The Trump Administration contends that a low-yield warhead would discourage potential adversaries from thinking that, if they used relatively small nuclear weapons in a regional conflict, the United States would shrink from retaliating (or threatening to respond) if the only nuclear weapons at its disposal were the considerably more destructive warheads currently in the U.S. arsenal. Critics of the proposal contend that deployment of new, low-yield weapons could increase the risk of nuclear war by making it easier for U.S. officials to consider their use in a limited conflict.

The House bill would have denied all funds requested for the program and included a provision (Section 1646) that would have barred the use of any funds for this purpose. A floor amendment to strike this provision was rejected by the House on a near-party-line vote of 201-221. The provision was not included in the enacted bill.

As enacted, the FY2020 NDAA authorizes more than 97% of the $682.4 million requested to develop a fleet of new ICBMs to replace the 400 Minuteman missiles currently deployed in silos located in Montana, North Dakota, and Wyoming. This total includes $552.4 million of the $570.4 million requested to continue development of the new missile, designated the Ground Based Strategic Defense (GBSD). It also includes, in the Energy Department's national security budget, $112.0 million â the entire amount requested -- to develop a new warhead (designated W87-1) to equip the new missile, in lieu of the W78 warhead carried by the Minuteman.

Section 1672 of the enacted bill prohibits any reduction in the number of deployed U.S. ICBMs, currently 400 missiles.

The Senate version of the bill would have authorized $22 million more than was requested for GBSD. Section 1664 of the Senate bill would have prohibited any reduction in the number of ICBMs

The House bill would have imposed a reduction of $140.0 million on the $682.4 million request for R&D related to a new ICBMâa cut of about 20%. This included a net reduction of $81.0 million for GBSD and a reduction of $59.0 million for the warhead. The House rejected by a vote of 164-264 an amendment to the House version of the bill that would have delayed the GBSD program and required an independent study of options to extend the service life of the currently deployed Minuteman missiles.

The NDAA conference report authorizes $712.4 million as requested to continue expanding the Energy Department's capacity for manufacturing so-called plutonium pits â the nuclear triggers that initiate the explosion of a thermonuclear bomb or missile warhead. This includes $241.1 million to begin construction of a new pit production facility at the Energy Department's Savannah River Site, near Aiken, GA. The new facility would put the Energy Department on track to meet a goal of being able to produce 80 pits per year by 2030, a goal set the by Trump Administration in 2018.

The House bill would have denied authorization of the $241.1 million requested for the Savanah River facility. Section 3114 of the House bill would have repealed a provision of law that codifies the 80 pit per year goal.

In general, the NDAA conference report support's the Administration requests to expand the U.S. arsenal of guided missiles that could accurately strike targets at ranges of 100 miles and more with conventional (that is, nonnuclear) warheads. ( Table 5 .)

As U.S. strategy has focused more sharply on Russia and China as potential adversaries, DOD has placed increasing emphasis on developing such weapons, partly because those two countries are developing defenses intended to keep U.S. forces at a distance.

The enacted version of the FY2020 NDAA authorizes the bulk of the Administration's $14.1 billion request for National Security Space operations, which includes funds for DOD's satellite acquisition, space launches, and other space-oriented activities. The requested amount is 17% higher than the amount appropriated for these activities in FY2019âa rate of increase more than triple the Administration's proposed 4.9% increase in the overall DOD budget.

The final bill authorizes most of the funds requested for DOD's most expensive acquisition programs for space systems, as the House and Senate versions would have done. (See Table 6 .)

As proposed by the Administration, the FY2020 NDAA establishes the U.S. Space Force as a separate armed service within the Department of the Air Force (a status analogous to that of the Marine Corps as a separate service within the Department of the Navy). The bill authorizes $72.4 million, as requested, to fund operation of the new organization.

The new organization is to be headed by a four-star general (designated Chief of Space Operations) who is to report directly to the Secretary of the Air Force. After one year, that officer is to become a member of the Joint Chiefs of Staff (JCS), in which capacity he or she may provide advice to the President, without going through the Air Force chain of command, after first informing the Secretary of Defense and the Chairman of the Joint Chiefs of Staff. Similarly, as a member of the JCS, the Chief of Space Operations may make recommendations to Congress, after informing the Secretary of Defense.

The enacted NDAA authorizes the Secretary of the Air Force to transfer into the new organization all military personnel currently assigned to the Air Force Space Command and other Air Force military personnel. The Administration had proposed transferring into the Space Force personnel currently assigned to all of DOD's space-oriented organizations.

The earlier House and Senate versions of the FY2020 NDAA each would have approved some elements of the proposed consolidation, though neither bill would have afforded the new space organization the degree of bureaucratic independence that the Administration proposed. The Senate bill would have authorized the requested $72.4 million for a Space Force within the Air Force to be overseen by a less senior civilian political appointee (an assistant secretary rather than an undersecretary). The House bill would have authorized $15.0 million for the new organization, which would have been designated a Space Corps and which would have had no civilian political overseer.

The enacted FY2020 NDAA approves the broad thrusts â and most of the detailsâ of the Administration's FY2020 anti-missile defense budget request. The request reflected the results of the Administration's Missile Defense Review, published in January 2019. That study reaffirmed ongoing DOD efforts to (1) expand and improve a network of interceptor missiles that could protect U.S. territory against a relatively small number of intercontinental ballistic missiles (ICBMs) and (2) deploy systems to defense U.S. allies and U.S. forces stationed abroad against attack by missiles of shorter range. ( Table 7 .)

Many of the enacted bill's differences with the budget request were linked to delays in the development of a more reliable warhead, designated the Redesigned Kill Vehicle (RKV), to be carried by the homeland defense system's interceptor missiles. On August 21, 2019, after the House and Senate each had passed their respective versions of the FY2020 NDAA, DOD cancelled the RKV project.

New Interceptor Missile and Additional Radars

The enacted bill authorizes a total of $602.7 million of the $843.8 million requested to develop an improved missile defense for U.S. territory that would include a new interceptor missile carrying the planned new warhead (RKV). The largest component of the net reduction from the request is a transfer of $140.0 million, associated with the RKV project, to develop improvements to the currently deployed homeland defense system. The bill also authorizes $173.4 million ($101.0 less than requested) for development work on a new radar to be located in Hawaii.

The House bill would have authorized $150.0 million less than requested for development of the new interceptor. The Senate bill would have authorized the amount requested.

The enacted bill authorizes a total of $53.8 million, distributed over several funding lines, to test the Navy's Standard missile against an ICBM. The Standard, which is part of the Navy's Aegis anti-missile system, was designed to intercept missiles of shorter range than ICBMs. However, new versions of the Standard theoretically would be capable of ICBM intercepts. Section 1680 of the FY2018 NDAA ( P.L. 115-91 ) directed DOD to conduct a test of Aegis against an ICBM-range target.

The House version of the bill would have eliminated the planned ICBM intercept test of Aegis, authorizing $12.1 million of the amount requested.

The Army presented its FY2020 budget request for weapons acquisition as "a bold shift" intended to place greater emphasis on shaping the force to deal with potential threats from Russia and China, as called for by the Administration's FY2018 National Defense Strategy. Compared with the five-year defense plan (FYDP) that had accompanied the Army's FY2019 budget request, the FY2020 FYDP would reduce previously planned spending for many systems currently in production to make funds available for accelerated development of successor weapons, better adapted to the newly emphasized "peer competitors."

The enacted version of the FY2020 NDAA largely supported the Army's revised spending plans for ground combat vehicles, anti-aircraft defenses, and long-range precision strike weapons. The versions passed initially by the House and Senate would have done likewise. (See Table 8 .)

The Army's modernization plan would reconstitute the service's short-range anti-aircraft defenses which had atrophied after the Soviet Union collapsed and DOD focused on counter-terrorism and related missions in the aftermath of 9/11. In this period, the Patriot missileâdesigned in the 1970s to intercept aircraftâwas adapted to intercept long-range ballistic missiles as the shortest-range component of a layered defense.

Since the turn of the century, DOD has focused more attention on other types of aerial threats which (because of their relatively short range or for other reasons) would challenge or thwart existing U.S. anti-missile/anti-aircraft defenses. These threats include unguided, short-range rockets and mortar shells used by insurgents; swarms of relatively small, armed drone aircraft; and technologically sophisticated cruise missiles, such as are deployed by Russia and China.

The conference report on the bill â like the House and Senate versions â generally support this renewed focus on anti-aircraft defense, which includes:

M-SHORAD (Maneuver-Short Range Air Defense), a variant of the Stryker combat vehicle equipped with and array of guns and guided missiles to protect maneuvering combat units against aerial threats; and IFPC (Indirect Fire Protection Capability), an array of sensors, missile launchers and various types of missiles to protect fixed sites.

The Navy's $23.8 billion shipbuilding budget request for FY2020 reflects a 2016 plan to increase the size of the fleet to 355 ships, a target some 15% higher than the force goal set by the previous Navy plan. The enacted version of the FY2020 NDAA â like the versions of the bill passed by the House and the Senate â generally supports the Navy program. The House-passed bill would have cut a total of $1.6 billion from the shipbuilding request, most of which the House Armed Services Committee justified as reflecting "excess cost growth." (See Table 9 .)

As enacted, the NDAA authorized the $2.35 billion requested for construction of two nuclear-powered aircraft carriers. The funding will be split between two carriersâcosting roughly $12 billion apieceâfor which a contract was signed in January 2019. One of the ships is slated for delivery to the Navy in 2028 and the other in 2032.

As a general rule, Congress requires DOD to budget for the entire cost of any weapon in a single year, with limited exceptions. However, in the case of certain high-priced items, such as carriers, Congress allows DOD to use incremental funding âspreading the cost of a ship or other item across the budgets of several fiscal years.

The enacted FY2020 NDAA would rein in spending on the Navy's plan to speed development of several types of relatively large, unmanned surface ships and submarines that could supplement the current force by distributing its firepower and sensor network across a larger number of platforms.

The FY2020 budget request includes a total of $628.8 million to develop these items, of which more than halfâ$372.5 millionâis to jump-start the acquisition of Large Unmanned Surface Vehicles (LUSVs), based on commercial ship designs and able to carry modular payloads including various types of anti-ship and land attack missiles. Reportedly, the Navy envisions LUSVs as being as long as 300 feet in length and displacing 2,000 tons, in which case they would be roughly half the size of the Perry -class missile frigates the Navy used in the 1980s and 1990s.

The conference report on the FY2020 NDAA authorizes the full amounts requested to develop a smaller unmanned surface vessel (designated MUSV) and a relatively large robot submarine with a payload volume of up to 2,000 cubic feet. However, it authorizes $196.5 millionâslightly more than half the requestâfor the LUSV project, funding one of the two vessels requested. The joint explanatory statement accompanying the conference report on the bill did not discuss conferees' rationale for the cut. The Senate Armed Services Committee, in its report on the original, Senate-passed version of the bill had questioned the Navy's plan to develop and procure these ships on an accelerated schedule, given their technological and operational novelty.

The FY2020 budget request sought to fund the procurement of 385 aircraft across the military services; this is 71 aircraft more than the total included in the projected FY2020 budget request published in early 2018. Generally speaking, the enacted version of the bill, like the versions passed earlier by the House and Senate -- authorizes the Administration's requests, subject to relatively minor additions and reductions reflecting routine congressional oversight.

One major departure from the request is an increase in the number of F-35 Joint Strike Fighters authorized.

To construct a barrier along the U.S.-Mexican border, which Congress has not explicitly authorized as military construction, the Trump Administration used various budget transfer and reprogramming authorities to make available a total of $6.1 billion comprising DOD program savings and unobligated funds from prior fiscal years. In addition, its FY2020 budget request sought $7.2 billion in barrier-related military construction funding, of which $3.6 billion would replenish prior year funds that were transferred to barrier construction and $3.6 billion that would fund new barrier construction in FY2020.

The enacted version of the FY2020 NDAA reduces from $8.0 billion (in FY2019) to $5.5 billion the total amount of DOD funding that could be transferred. It authorizes none of the $7.2 billion request in connection with the border barrier project.

The Senate bill would have reduced transfer authority by a smaller amount, the House bill by a larger amount. In addition, Sections 1046 and 2801 of the House bill would have prohibited the use of defense funds appropriated between FY2015 and FY2020 for barrier construction. ( Table 11 .)

PFAS (per- and polyfluoroalkyl substances) are a large, diverse group of fluorinated compounds that have been used for several decades in numerous commercial, industrial, and U.S. military applications including use as an ingredient in aqueous film forming foam (AFFF) for extinguishing petroleum-based liquid fuel fires. Releases of certain PFAS have been detected in drinking water sources, other environmental media, and dairy milk at various locations, some of which have been associated with the use of AFFF at U.S. military installations. The House and Senate versions of the FY2020 NDAA each contained multiple provisions related to PFAS that would require DOD, the U.S. Environmental Protection Agency, and other agencies to address potential risks of these chemicals under existing laws or new authorities.

The conference agreement includes PFAS provisions related to drinking water and agricultural water sources, reporting of releases on the Toxics Release Inventory, data calls and significant new use notices under the Toxic Substances Control Act, environmental remediation at active and decommissioned U.S. military installations and National Guard facilities, DOD use and disposal of AFFF, and other purposes. The conference agreement does not include provisions regarding PFAS standards under the Clean Water Act or Safe Drinking Water Act, or liability for PFAS releases under the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA often referred to as "Superfund").

Paid Parental Leave for Federal Employees

Sections 1121-1126 of the initial House-passed bill would have provided 12 weeks of paid leave to federal government employees covered by Title V, Chapter 63 of the U.S. Code for reasons covered by the Family and Medical Leave Act of 1993 (FMLA), as amended ( P.L. 103-3 ). That legislation provides entitlement for such leave in the event of the employee's own serious health condition and certain family-related situations including the birth, adoption, or fostering of a child; the serious illness of certain family members; and military family needs. The bill would have permitted the Office of Personnel Management to increase the amount of such paid leave to a total of 16 weeks. The same paid leave entitlement would have been provided to Legislative Branch employees covered by the Congressional Accountability Act (CAA) of 1995. Conforming amendments would have been included to extend benefits to Government Accountability Office (GAO) employees and certain TSA employees.

The initial Senate-passed bill included no provision related to this subject.

Sections 7601-7606 of the enacted version of the bill entitle federal employees (as described above) to 12 weeks of paid parental leave in connection with the birth, adoption, or fostering of a child. Federal civil service employees must meet the FMLA 12-months-of-service requirements before becoming eligible for the paid parental leave benefit; by contrast the FMLA eligibility requirements for Legislative Branch employees covered by the CAA and for GAO employees do not apply to the paid parental leave benefit. In addition, use of the paid parental leave benefit by federal civil service employees is conditioned upon an agreement from the employee that he or she will return to work for the employing agency for 12 workweeks following the conclusion of that leave. Should an employee fail to do so and if certain conditions enumerated in the bill do not apply, the employing agency may recoup its contributions to the employee's health care premiums made during the period of leave. No such requirement is provided for Legislative Branch employees covered by the CAA nor for GAO employees.

Following, in numerical order, are CRS products cited in this report, including those cited in tables by only their reference number:

CRS Report RS20643, Navy Ford (CVN-78) Class Aircraft Carrier Program: Background and Issues for Congress , by Ronald O'Rourke

CRS Report RL30563, F-35 Joint Strike Fighter (JSF) Program , by Jeremiah Gertler

CRS Report RL32109, Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress , by Ronald O'Rourke

CRS Report RL32418, Navy Virginia (SSN-774) Class Attack Submarine Procurement: Background and Issues for Congress , by Ronald O'Rourke

CRS Report RL32665, Navy Force Structure and Shipbuilding Plans: Background and Issues for Congress , by Ronald O'Rourke

CRS Report RL33640, U.S. Strategic Nuclear Forces: Background, Developments, and Issues , by Amy F. Woolf

CRS Report RL33745, Navy Aegis Ballistic Missile Defense (BMD) Program: Background and Issues for Congress , by Ronald O'Rourke

CRS Report R41129, Navy Columbia (SSBN-826) Class Ballistic Missile Submarine Program: Background and Issues for Congress , by Ronald O'Rourke

CRS Report R41909, Multiyear Procurement (MYP) and Block Buy Contracting in Defense Acquisition: Background and Issues for Congress , by Ronald O'Rourke

CRS Report R42972, Sequestration as a Budget Enforcement Process: Frequently Asked Questions , by Megan S. Lynch

CRS Report R43049, U.S. Air Force Bomber Sustainment and Modernization: Background and Issues for Congress , by Jeremiah Gertler

CRS Report R43240, The Army's Armored Multi-Purpose Vehicle (AMPV): Background and Issues for Congress , by Andrew Feickert

CRS Report R43543, Navy LPD-17 Flight II and LHA Amphibious Ship Programs: Background and Issues for Congress , by Ronald O'Rourke

CRS Report R43546, Navy John Lewis (TAO-205) Class Oiler Shipbuilding Program: Background and Issues for Congress , by Ronald O'Rourke

CRS Report R43838, Renewed Great Power Competition: Implications for DefenseâIssues for Congress , by Ronald O'Rourke

CRS Report R44039, The Defense Budget and the Budget Control Act: Frequently Asked Questions , by Brendan W. McGarry

CRS Report R44274, The Family and Medical Leave Act: An Overview of Title I , by Sarah A. Donovan

CRS Report R44442, Energy and Water Development Appropriations: Nuclear Weapons Activities , by Amy F. Woolf

CRS Report R44463, Air Force B-21 Raider Long-Range Strike Bomber , by Jeremiah Gertler

CRS Report R44835, Paid Family Leave in the United States , by Sarah A. Donovan

CRS Report R44891, U.S. Role in the World: Background and Issues for Congress , by Ronald O'Rourke and Michael Moodie

CRS Report R44968, Infantry Brigade Combat Team (IBCT) Mobility, Reconnaissance, and Firepower Programs , by Andrew Feickert

CRS Report R44972, Navy Frigate (FFG[X]) Program: Background and Issues for Congress , by Ronald O'Rourke

CRS Report R45349, The 2018 National Defense Strategy: Fact Sheet , by Kathleen J. McInnis

CRS Report R45519, The Army's Optionally Manned Fighting Vehicle (OMFV) Program: Background and Issues for Congress , by Andrew Feickert

CRS Report R45757, Navy Large Unmanned Surface and Undersea Vehicles: Background and Issues for Congress , by Ronald O'Rourke

CRS Report R45793, PFAS and Drinking Water: Selected EPA and Congressional Actions , by Elena H. Humphreys and Mary Tiemann

CRS Report R45937, Military Funding for Southwest Border Barriers , by Christopher T. Mann

CRS Report R45986, Federal Role in Responding to Potential Risks of Per- and Polyfluoroalkyl Substances (PFAS) , coordinated by David M. Bearden

CRS Report R45996, Precision-Guided Munitions: Background and Issues for Congress , by John R. Hoehn

CRS Report R45998, Contaminants of Emerging Concern under the Clean Water Act , by Laura Gatz

CRS Report R46107, FY2020 National Defense Authorization Act: Selected Military Personnel Issues , coordinated by Bryce H. P. Mendez

CRS In Focus IF10541, Defense Primer: Ballistic Missile Defense , by Stephen M. McCall

CRS In Focus IF10999, Defense's 30-Year Aircraft Plan Reveals New Details , by Jeremiah Gertler

CRS In Focus IF11102, Military Medical Malpractice and the Feres Doctrine , by Bryce H. P. Mendez and Kevin M. Lewis

CRS In Focus IF11143, A Low-Yield, Submarine-Launched Nuclear Warhead: Overview of the Expert Debate , by Amy F. Woolf

CRS In Focus IF11203, Proposed Civilian Personnel System Supporting "Space Force , " by Alan Ott

CRS In Focus IF11219, Regulating Drinking Water Contaminants: EPA PFAS Actions , by Mary Tiemann and Elena H. Humphreys

CRS In Focus IF11244, FY2020 National Security Space Budget Request: An Overview , by Stephen M. McCall and Brendan W. McGarry

CRS In Focus IF11326, Military Space Reform: FY2020 NDAA Legislative Proposals , by Stephen M. McCall

CRS In Focus IF11353, Defense Primer: U.S. Precision-Guided Munitions , by John R. Hoehn

CRS In Focus IF11367, Army Future Vertical Lift (FVL) Program , by Jeremiah Gertler

CRS Insight IN10931, U.S. Army's Initial Maneuver, Short-Range Air Defense (IM-SHORAD) System , by Andrew Feickert

CRS Insight IN11052, The Defense Department and 10 U.S.C. 284: Legislative Origins and Funding Questions , by Liana W. Rosen

CRS Legal Sidebar LSB10242, Can the Department of Defense Build the Border Wall? , by Jennifer K. Elsea, Edward C. Liu, and Jay B. Sykes

CRS Legal Sidebar LSB10305, The Feres Doctrine: Congress, the Courts, and Military Servicemember Lawsuits Against the United States , by Kevin M. Lewis

CRS Legal Sidebar LSB10316, Eliminating the SBP-DIC Offset for Surviving Spouses of Military Servicemembers: Current Proposals and Related Issues , by Mainon A. Schwartz