Navy DDG-51 and DDG-1000 Destroyer
Programs: Background and Issues for
Congress

Updated February 24, 2021
Congressional Research Service
https://crsreports.congress.gov
RL32109




Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress

Summary
The Navy began procuring Arleigh Burke (DDG-51) class destroyers, also known as Aegis
destroyers, in FY1985, and a total of 87 have been procured through FY2021, including 2 in
FY2021. From FY1989 through FY2005, DDG-51s were procured in annual quantities of two to
five ships per year. Since FY2010, they have been procured in annual quantities of one to three
ships per year. The first DDG-51 entered service in 1991. The DDG-51 design has been modified
and updated periodically over the years.
DDG-51s are being procured in FY2018-FY2022 under a multiyear procurement (MYP) contract
that Congress approved as part of its action on the Navy’s FY2018 budget. DDG-51s procured in
FY2017 and subsequent years are being built to a design called the Flight III design, which
incorporates a new and more capable radar called the SPY-6 radar or the Air and Missile Defense
Radar (AMDR).
The Navy refers to its cruisers and destroyers collectively as large surface combatants (LSCs).
The Navy’s current force-level goal, released in December 2016, calls for achieving and
maintaining a fleet of 355 ships, including 104 LSCs. On December 9, 2020, the outgoing Trump
Administration released a document that can be viewed as its own vision for future Navy force
structure and/or a draft version of the FY2022 30-year Navy shipbuilding plan. The document
presents an envisioned Navy force-level goal for achieving by 2045 a Navy with a more
distributed fleet architecture, including 382 to 446 manned ships and 143 to 242 large unmanned
vehicles. Within the total of 382 to 446 manned ships, the document calls for maintaining a force
of 73 to 88 LSCs. In determining its Navy force-level goals and shipbuilding plans, the Biden
Administration can choose to adopt, revise, or set aside this document.
Issues for Congress include the future LSC force-level goal, annual DDG-51 procurement
quantities for FY2022 and subsequent fiscal years, and how the Navy proposes to transition
several years from now from procurement of DDG-51s to procurement of a successor destroyer
design now in development called the DDG(X). Regarding annual DDG-51 procurement
quantities and the transition to DDG(X) procurement, recent documents have shown the
following:
 The Navy’s FY2020 budget submission and FY2020 30-year shipbuilding plan
projected DDG-51s being procured during the period FY2022-FY2025 in annual
quantities of 2-3-3-2, with FY2025 being the final year of DDG-51 procurement
and the year that the first DDG(X) would be procured.
 The Navy’s FY2021 budget submission projected DDG-51s being procured
during the period FY2022-FY2025 in annual quantities of 2-1-2-1, and for DDG-
51 procurement to end with the procurement of two final ships that would be
procured in either FY2026 (both ships) or FY2026 and FY2027 (one ship each
year). Under this budget submission, DDG(X) procurement might begin around
FY2028.
 The December 9, 2020, document released by the outgoing Trump
Administration projected DDG-51s being procured during the period FY2022-
FY2026 in annual quantities of 2-2-2-2-2. The document did not specify the final
year of DDG-51 procurement, but press reports suggest that the Navy wants to
procure the first DDG(X) around FY2028.
For more on the DDG(X) program, see CRS In Focus IF11679, Navy DDG(X) Future Large
Surface Combatant Program: Background and Issues for Congress
, by Ronald O'Rourke.
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Contents
Introduction ..................................................................................................................................... 1
Background ..................................................................................................................................... 1

Navy’s Force of Large Surface Combatants (LSCs) ................................................................. 1
LSC Definition .................................................................................................................... 1
LSC Force Levels ............................................................................................................... 1

DDG-51 Program ...................................................................................................................... 2
Overview ............................................................................................................................. 2
Design Changes .................................................................................................................. 3
Multiyear Procurement (MYP) ........................................................................................... 3
Shipbuilders, Combat System Lead, and Radar Makers ..................................................... 4
Modernization of In-Service Ships ..................................................................................... 4

DDG-1000 Program .................................................................................................................. 4
Surface Combatant Construction Industrial Base ..................................................................... 5
Issues for Congress .......................................................................................................................... 5
Future LSC Force-Level Goal ................................................................................................... 5
DDG-51 Procurement Quantities and Transition to DDG(X) ................................................... 6
Potential Impact of COVID-19 Pandemic ................................................................................ 6
Cost, Technical, and Schedule Risk in Flight III DDG-51 Effort ............................................. 7
October 2019 CBO Report .................................................................................................. 7
June 2020 GAO Report ....................................................................................................... 7

Legislative Activity for FY2022 ...................................................................................................... 9
Legislative Activity for FY2021 .................................................................................................... 10
Summary of Congressional Action on FY2021 Funding Request .......................................... 10
FY2021 National Defense Authorization Act (H.R. 6395/S. 4049/P.L. 116-283) .................. 10

House ................................................................................................................................ 10
Senate (Committee Report) ............................................................................................... 12
Senate (Floor Consideration) ............................................................................................ 14
Conference ........................................................................................................................ 15
FY2021 DOD Appropriations Act (H.R. 7617/S. XXXX/Division C of H.R. 133/P.L.
116-260) ............................................................................................................................... 17
House ................................................................................................................................ 17
Senate ................................................................................................................................ 17
Conference ........................................................................................................................ 18

Figures
Figure 1. DDG-51 Class Destroyer ................................................................................................. 3

Figure A-1. DDG-1000 Class Destroyer ....................................................................................... 20

Tables
Table 1. Congressional Action on FY2021 Funding Request........................................................ 10
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Table A-1. Estimated Combined Procurement Cost of DDG-1000, DDG-1001, and DDG-
2002 ............................................................................................................................................ 25

Appendixes
Appendix. Additional Background Information on DDG-1000 Program ..................................... 20

Contacts
Author Information ........................................................................................................................ 30

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Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress

Introduction
This report presents background information and potential oversight issues for Congress on the
Navy’s Arleigh Burke (DDG-51) and Zumwalt (DDG-1000) class destroyer programs. The Navy
began procuring DDG-51s, also known as Aegis destroyers, in FY1985, and a total of 87 have
been procured through FY2021, including 2 in FY2021. The Navy procured three DDG-1000
class destroyers in FY2007-FY2009 and plans no further procurement of DDG-1000s.
Key issues for Congress concern the Navy’s future force-level goal for large surface combatants
(or LSCs, meaning cruisers and destroyers), annual DDG-51 procurement quantities for FY2022
and subsequent fiscal years, and how the Navy proposes to transition several years from now
from procurement of DDG-51s to procurement of a successor destroyer design now in
development called the DDG(X). Decisions that Congress makes on these issues could
substantially affect Navy capabilities and funding requirements, and the U.S. shipbuilding
industrial base.
For more on the DDG(X) program, see CRS In Focus IF11679, Navy DDG(X) Future Large
Surface Combatant Program: Background and Issues for Congress
, by Ronald O'Rourke.
Background
Navy’s Force of Large Surface Combatants (LSCs)
LSC Definition
Decades ago, the Navy’s cruisers were considerably larger and more capable than its destroyers.
In the years after World War II, however, the Navy’s cruiser designs in general became smaller
while its destroyer designs in general became larger. As a result, since the 1980s there has been
substantial overlap in size and capability of Navy cruisers and destroyers. (The Navy’s new
Zumwalt [DDG-1000] class destroyers, in fact, are considerably larger than the Navy’s cruisers.)
In part for this reason, the Navy now refers to its cruisers and destroyers collectively as large
surface combatants (LSCs)
, and distinguishes these ships from the Navy’s small surface
combatants (SSCs)
, the term the Navy now uses to refer collectively to its frigates, Littoral
Combat Ships (LCSs), mine warfare ships, and patrol craft. The Navy’s annual 30-year
shipbuilding plan, for example, groups the Navy’s surface combatants into LSCs and SSCs.1
LSC Force Levels
Current Force-Level Goal
The Navy’s current force-level goal, released in December 2016, calls for achieving and
maintaining a fleet of 355 ships, including 104 LSCs.2

1 The Navy sometimes also uses the term Cru-Des (an abbreviation of cruiser-destroyer, pronounced “crew-dez”) to
refer collectively to its cruisers and destroyers.
2 For more on the 355-ship force-level goal, see CRS Report RL32665, Navy Force Structure and Shipbuilding Plans:
Background and Issues for Congress
, by Ronald O'Rourke.
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Potential New Force-Level Goal
The Navy and the Department of Defense (DOD) have been working since 2019 to develop a
successor for the 355-ship force-level goal. On December 9, 2020, the outgoing Trump
Administration released a document that can be viewed as its own vision for future Navy force
structure and/or a draft version of the FY2022 30-year Navy shipbuilding plan. The document
presents an envisioned Navy force-level goal for achieving by 2045 a Navy with a more
distributed fleet architecture, including 382 to 446 manned ships and 143 to 242 large unmanned
vehicles. Within the total of 382 to 446 manned ships, the document calls for maintaining a force
of 73 to 88 LSCs. In determining its Navy force-level goals and shipbuilding plans, the Biden
Administration can choose to adopt, revise, or set aside this document.3
Actual Force Level as of End of FY2020
As of the end of FY2020, the Navy’s force of LSC’s included 91 LSCs, including 22 Ticonderoga
(CG-47) class cruisers,4 68 DDG-51s, and one Zumwalt (DDG-1000) class destroyer.
DDG-51 Program
Overview
The DDG-51 program was initiated in the late 1970s.5 The first DDG-51 was procured in FY1985
and entered service in 1991. A total of 87 DDG-51s have been procured through FY2021,
including 2 in FY2021. From FY1989 through FY2005, DDG-51s were procured in annual
quantities of two to five ships per year. Since FY2010, they have been procured in annual
quantities of one to three ships per year. (The Navy did not procure any DDG-51s during the
period FY2006-FY2009. Instead, the Navy in FY2007-FY2009 procured three Zumwalt [DDG-
1000] class destroyers, which are discussed later in this report.) The DDG-51 program is one of
the longest-running shipbuilding programs in Navy history, and the DDG-51 class, in terms of
number of hulls, is one of the Navy’s largest classes of ships since World War II.
DDG-51s (Figure 1) are multi-mission destroyers with an emphasis on air defense (which the
Navy refers to as anti-air warfare, or AAW) and blue-water (mid-ocean) operations. DDG-51s,
like the Navy’s 22 Ticonderoga (CG-47) class cruisers, are equipped with the Aegis combat
system, an integrated ship combat system named for the mythological shield that defended Zeus.
CG-47s and DDG-51s consequently are often referred to as Aegis cruisers and Aegis destroyers,
respectively, or collectively as Aegis ships. The Aegis system has been updated several times over
the years. Many DDG-51s (and also some CG-47s) have a capability for conducting ballistic
missile defense (BMD) operations.6

3 For more on the December 9, 2020 document, see CRS Report RL32665, Navy Force Structure and Shipbuilding
Plans: Background and Issues for Congress
, by Ronald O'Rourke.
4 A total of 27 CG-47s (CGs 47 through 73) were procured for the Navy between FY1978 and FY1988; the ships
entered service between 1983 and 1994. The first five ships in the class (CGs 47 through 51), which were built to an
earlier technical standard in certain respects, were judged by the Navy to be too expensive to modernize and were
removed from service in 2004-2005, leaving 22 ships in operation (CGs 52 through 73).
5 The program was initiated with the aim of developing a surface combatant to replace older destroyers and cruisers
that were projected to retire in the 1990s. The DDG-51 was conceived as an affordable complement to the Navy’s
Ticonderoga (CG-47) class Aegis cruisers. For an early discussion of the DDG-51 program, see Alva M. Bowen and
Ronald O’Rourke, “DDG-51 and the Future Surface Navy,” U.S. Naval Institute Proceedings, May 1985: 176-189.
6 For more on Navy BMD programs, see CRS Report RL33745, Navy Aegis Ballistic Missile Defense (BMD) Program:
Background and Issues for Congress
, by Ronald O'Rourke.
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Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress

Figure 1. DDG-51 Class Destroyer

Source: U.S. Navy file photograph.
Design Changes
The DDG-51 design has been modified and updated periodically over the years. The first 28
DDG-51s (i.e., DDGs 51 through 78) are called Flight I/II DDG-51s. In FY1994, the Navy
shifted DDG-51 procurement to the Flight IIA DDG-51 design, which incorporated certain
changes, including the addition of a helicopter hangar. A total of 47 Flight IIA DDG-51s (i.e.,
DDG-79 through DDG-124, plus DDG-127)7 were procured through FY2016.
In FY2017, the Navy shifted DDG-51 procurement to the Flight III DDG-51 design, which
incorporates a new and more capable radar called the SPY-6 radar or the Air and Missile Defense
Radar (AMDR), as well as associated changes to the ship’s electrical power and cooling systems.
DDGs 125 and higher, except for DDG-127 noted above, are to be Flight III DDG-51s.
Multiyear Procurement (MYP)
As part of its action on the Navy’s FY2018 budget, Congress granted the Navy authority to use a
multiyear procurement (MYP) contract for DDG-51s planned for procurement in FY2018-
FY2022. This is the fourth MYP contract for the DDG-51 program—previous DDG-51 MYP
contracts covered DDG-51s procured in FY2013-FY2017, FY2002-FY2005, and FY1998-
FY2001.

7 The hull-number discontinuity regarding DDG-127 is an administrative consequence of the ship having been funded
as a Congressional addition to the Navy’s proposed FY2016 shipbuilding request.
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Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress

Shipbuilders, Combat System Lead, and Radar Makers
DDG-51s are built by General Dynamics/Bath Iron Works (GD/BIW) of Bath, ME, and
Huntington Ingalls Industries/Ingalls Shipbuilding (HII/Ingalls) of Pascagoula, MS. Lockheed is
the lead contractor for the Aegis system installed on all DDG-51s. The SPY-6—the primary radar
for the Aegis system on Flight III DDG-51s—is made by Raytheon.
Modernization of In-Service Ships
The Navy is modernizing existing DDG-51s (and some CG-47s) so as to maintain their mission
and cost-effectiveness out to the end of their projected service lives. Older CRS reports provide
additional historical and background information on the DDG-51 program.8
DDG-1000 Program
As noted earlier, in FY2007-FY2009, during the time when the Navy was not procuring DDG-
51s, the Navy instead procured three Zumwalt (DDG-1000) class destroyers. The Navy plans no
further procurement of DDG-1000s.
DDG-1000s are multi-mission destroyers with an originally intended emphasis on naval surface
fire support (NSFS) and operations in littoral (i.e., near-shore) waters. Consistent with that
mission orientation, the ship was designed with two new-design 155mm guns called Advanced
Gun Systems (AGSs). The AGSs were to fire a new 155mm, gun-launched, rocket-assisted
guided projectile called the Long-Range Land-Attack Projectile (LRLAP, pronounced LUR-lap).
In November 2016, however, it was reported that the Navy had decided to stop procuring LRLAP
projectiles because the projected unit cost of each projectile had risen to at least $800,000.9 The
Navy to date has not announced a replacement munition for the AGSs.10
In the meantime, it was reported in December 2017 that, due to shifts in the international security
environment and resulting shifts in Navy mission needs, the mission orientation of the DDG-
1000s will be shifted from an emphasis on NSFS to an emphasis on surface strike, meaning the
use of missiles to attack surface ships and perhaps also land targets.11 Under this new plan, the
mix of missiles carried in the 80 vertical launch system (VLS) tubes of each DDG-1000 may now
feature a stronger emphasis on anti-ship and land-attack cruise missiles. The two AGSs on each
DDG-1000 will, for the time being at least, remain for the most part dormant, pending a final
decision on whether to procure a replacement munition for the AGSs (which would require
modifying the AGSs and their below-deck munition-handling equipment, since both were

8 See CRS Report 94-343, Navy DDG-51 Destroyer Procurement Rate: Issues and Options for Congress, by Ronald
O’Rourke (April 25, 1994; out of print and available to congressional clients directly from the author), and CRS Report
80-205, The Navy’s Proposed Arleigh Burke (DDG-51) Class Guided Missile Destroyer Program: A Comparison With
An Equal-Cost Force Of Ticonderoga (CG-47) Class Guided Missile Destroyers
, by Ronald O’Rourke (November 21,
1984; out of print and available to congressional clients directly from the author).
9 Christopher P. Cavas, “New Warship’s Big Guns Have No Bullets,” Defense News, November 6, 2016; Sam
LaGrone, “Navy Planning on Not Buying More LRLAP Rounds for Zumwalt Class,” USNI News, November 7, 2016;
Ben Guarino, “The Navy Called USS Zumwalt A Warship Batman Would Drive. But at $800,000 Per Round, Its
Ammo Is Too Pricey to Fire,” Washington Post, November 8, 2016.
10 See Sam LaGrone, “No New Round Planned For Zumwalt Destroyer Gun System; Navy Monitoring Industry,” USNI
News
, January 11, 2018; Richard Abott, “Navy Still Has No Plans For DDG-1000 Gun Ammo,” Defense Daily,
January 12, 2018: 1-2.
11 Megan Eckstein, “New Requirements for DDG-1000 Focus on Surface Strike,” USNI News, December 4, 2017. See
also Richard Abott, “Navy Will Focus Zumwalt On Offensive Surface Strike,” Defense Daily, December 5, 2017;
David B. Larter, “The Navy’s Stealth Destroyers to Get New Weapons and a New Mission: Killing Ships,” Defense
News
, February 15, 2018.
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designed specifically for LRLAP), or instead pursue another option, such as removing the AGSs
and their below-deck equipment and replacing them with additional VLS tubes.
For additional background information on the DDG-1000 program, see the Appendix.
Surface Combatant Construction Industrial Base
All cruisers and destroyers procured since FY1985 have been built at GD/BIW and HII/Ingalls.
Both yards have long histories of building larger surface combatants. Construction of Navy
surface combatants in recent years has accounted for virtually all of GD/BIW’s ship-construction
work and for a significant share of HII/Ingalls’ ship-construction work. (HII/Ingalls also builds
amphibious ships for the Navy and cutters for the Coast Guard.) Navy surface combatants are
overhauled, repaired, and modernized at GD/BIW, HII/Ingalls, and other U.S. shipyards.
Lockheed Martin and Raytheon are generally considered the two leading Navy surface combatant
radar makers and combat system integrators. Lockheed is the lead contractor for the DDG-51
combat system (the Aegis system), while Raytheon is the lead contractor for the DDG-1000
combat system, the core of which is called the Total Ship Computing Environment Infrastructure
(TSCE-I). Lockheed has a share of the DDG-1000 combat system, and Raytheon has a share of
the DDG-51 combat system. Lockheed, Raytheon, and Northrop competed to be the maker of the
AMDR to be carried by the Flight III DDG-51. On October 10, 2013, the Navy announced that it
had selected Raytheon to be the maker of the AMDR, now called the SPY-6 radar.
The surface combatant construction industrial base also includes hundreds of additional firms that
supply materials and components. The financial health of Navy shipbuilding supplier firms has
been a matter of concern in recent years, particularly since some of them are the sole sources for
what they make for Navy surface combatants. Several Navy-operated laboratories and other
facilities support the Aegis system and other aspects of the DDG-51 and DDG-1000 programs.
Issues for Congress
Future LSC Force-Level Goal
One issue for Congress concerns the future LSC force-level goal. In connection with this issue, it
can be noted that, compared to the Navy’s current force-level goal for a fleet of 355 ships,
including 104 LSCs, the December 9, 2020, shipbuilding document released by the outgoing
Trump Administration calls for a larger total number of manned ships (382 to 446) but a smaller
number of LSCs (73 to 88). This is because the December 9, 2020, shipbuilding document
proposes shifting the Navy to a more distributed force architecture that would feature
 a smaller proportion of larger ships (such as large-deck aircraft carriers, cruisers,
destroyers, large amphibious ships, and large resupply ships);
 a larger proportion of smaller ships (such as frigates, corvettes, smaller
amphibious ships, smaller resupply ships, and perhaps smaller aircraft carriers);
and
 a new third tier of surface vessels about as large as corvettes or large patrol craft
that will be either lightly manned, optionally manned, or unmanned, as well as
large unmanned underwater vehicles (UUVs).
Navy and DOD leaders believe that shifting to a more distributed fleet architecture is
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Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress

operationally necessary, to respond effectively to the improving maritime anti-
access/area-denial (A2/AD) capabilities of other countries, particularly China;
technically feasible as a result of advances in technologies for unmanned
vehicles (UVs) and for networking widely distributed maritime forces that
include significant numbers of UVs; and
affordable—no more expensive, and possibly less expensive, than the current
fleet architecture, for a given aggregate level of Navy capability.12
Reducing the LSC force-level goal from 104 ships to a smaller number could affect issues such as
when to retire older LSCs and how many new LSCs to procure each year (see next section).
DDG-51 Procurement Quantities and Transition to DDG(X)
Another issue for Congress concerns annual DDG-51 procurement quantities in FY2022 and
subsequent fiscal years, and how the Navy proposes to transition several years from now from
procurement of DDG-51s to procurement of a successor destroyer design now in development
called the DDG(X). Navy plans for transitioning from procurement of DDG-51s to procurement
of DDG(X)s have been an oversight focus for the defense committees in their reviews and
markups of the Navy’s proposed FY2020 and FY2021 budgets. Decisions regarding annual
DDG-51 procurement quantities and the transition to DDG(X) procurement will affect Navy
capabilities and funding requirements and the U.S. shipbuilding industrial base. Recent
documents have shown the following:
 The Navy’s FY2020 budget submission and FY2020 30-year shipbuilding plan
projected DDG-51s being procured during the period FY2022-FY2025 in annual
quantities of 2-3-3-2, with FY2025 being the final year of DDG-51 procurement
and the year that the first DDG(X) would be procured.
 The Navy’s FY2021 budget submission projected DDG-51s being procured
during the period FY2022-FY2025 in annual quantities of 2-1-2-1, and for DDG-
51 procurement to end with the procurement of two final ships that would be
procured in either FY2026 (both ships) or FY2026 and FY2027 (one ship each
year). Under this budget submission, DDG(X) procurement might begin around
FY2028.
 The December 9, 2020, document released by the outgoing Trump
Administration projected DDG-51s being procured during the period FY2022-
FY2026 in annual quantities of 2-2-2-2-2. The document did not specify the final
year of DDG-51 procurement, but press reports suggest that the Navy wants to
procure the first DDG(X) around FY2028.
For more on the DDG(X) program, see CRS In Focus IF11679, Navy DDG(X) Future Large
Surface Combatant Program: Background and Issues for Congress
, by Ronald O'Rourke.
Potential Impact of COVID-19 Pandemic
One issue for Congress concerns the potential impact of the COVID-19 pandemic on the
execution of U.S. military shipbuilding programs, including the DDG-51 program. For additional

12 For additional discussion about shifting the Navy to a more distributed architecture, see CRS Report RL32665, Navy
Force Structure and Shipbuilding Plans: Background and Issues for Congress
, by Ronald O'Rourke.
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Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress

discussion of this issue, see CRS Report RL32665, Navy Force Structure and Shipbuilding Plans:
Background and Issues for Congress
, by Ronald O'Rourke.
Cost, Technical, and Schedule Risk in Flight III DDG-51 Effort
Another issue for Congress concerns cost, technical, and schedule risk for the Flight III DDG-51.
October 2019 CBO Report
An October 2019 Congressional Budget Office (CBO) report on the cost of the Navy’s
shipbuilding programs stated the following about the Flight III DDG-51:
To meet combatant commanders’ goal of improving future ballistic missile defense
capabilities beyond those provided by existing DDG-51s—and to replace 15 Ticonderoga
class cruisers when they are retired in the 2020s—the Navy is substantially modifying the
design of the DDG-51 Flight IIA destroyer to create a Flight III configuration. That
modification will incorporate the new Air and Missile Defense Radar (AMDR) or SPY-6,
which will be larger and, recent testing indicates, nearly 100 times more powerful than the
radar on current DDG-51s. For the AMDR to operate effectively in the new Flight III
configuration, however, the ships must have a greater capacity to generate electrical power
and cool major systems.
With those improvements incorporated into the design of the Flight III and the associated
increases in the ships’ displacement, CBO estimates that the average cost per ship over the
entire production run would be $1.8 billion—about 7 percent more than the Navy’s
estimate of $1.7 billion. Costs could be higher or lower than CBO’s estimate, however,
depending on the eventual cost and complexity of the AMDR and the associated changes
to the ship’s design to integrate the new radar. Completion of the first Flight III ship is
several years away.13
June 2020 GAO Report
A June 2020 Government Accountability Office (GAO) report assessing selected DOD
acquisition programs stated the following in its assessment of the Flight III DDG-51:
Current Status
Flight III ships include considerable changes to DDG 51’s design to incorporate the
AN/SPY-6(V)1 radar and restore ship weight and stability safety margins. The program
delayed the start of power and integration testing for the AN/SPY-6(V)1 radar from
January 2019 to April 2020 due to software-related deficiencies that, according to program
officials, are now resolved. Despite this delay, the Navy plans to deliver equipment,
complete testing and installation on the ship, and activate the combat system for shipboard
testing by January 2022. Further, it expects both the radar and software developed for the
ship’s combat system to be delivered before the power and integration testing is completed
at the combat system development site, limiting opportunities to fix any issues prior to
activation.
The Navy plans to complete an integrated test and evaluation master plan for the ship,
AN/SPY-6(V)1 radar, and the Aegis combat system by the time of combat system
activation in January 2022. The plan, according to Navy officials, will not include the use
of an unmanned self-defense test ship, although DOD’s Director, Operational Test and
Evaluation and the Navy previously disagreed on whether an unmanned ship was necessary

13 Congressional Budget Office, An Analysis of the Navy’s Fiscal Year 2020 Shipbuilding Plan, October 2019, p. 24.
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to validate the end-to-end performance of Flight III ships—including the self-defense
capability—during operational testing.
The Navy continues construction on the lead Flight III ship, DDG 125, with plans for
delivery in fiscal year 2023. Construction of the second ship is planned to start in April
2020. Officials report that the Navy has procured 11 ships using multiyear procurement
authority and plans to award a contract for a 12th ship in fiscal year 2020. The current
acquisition strategy includes 22 ships but, according to Navy officials, the total number of
Flight III ships depends on the Navy’s plans for its future large surface combatant ships.
Program Office Comments
We provided a draft of this assessment to the program office for review and comment. The
program office provided technical comments, which we incorporated where appropriate.
The program stated it has delivered 67 ships and is on track for delivery and initial
capability of the first Flight III ship. According to the program, it rebaselined the radar test
and delivery schedule to better align production and testing and is on track to complete
radar testing prior to the start of shipboard testing. Further, the program said the
development of the radar and software are on track to support integration.14
Regarding the AMDR specifically, the report stated the following:
Technology Maturity, Design Stability, and Production Readiness
In April 2019, the Navy approved AMDR to procure its 10th low-rate initial production
radar in fiscal year 2020. According to the program, it has mature critical technologies, a
stable design, and production processes in control. However, we continue to disagree that
the technologies are fully mature. While the Navy continues to demonstrate some
technologies through land-based testing at its Pacific Missile Range Facility (PMRF) and
plans to integrate AMDR with the Aegis combat system at a separate land-based site for
simulation and testing, AMDR’s critical technologies cannot be assessed as fully mature
until the Navy integrates AMDR and Aegis on the lead DDG 51 Flight III ship in 2022
during the Aegis Light Off (ALO) event. Following ALO, the Navy will operationally test
AMDR and Aegis in a realistic, at-sea environment on the lead DDG 51 Flight III ship in
2023. While AMDR’s design is currently stable, it remains at risk for disruption until the
Navy completes this testing. In part, this risk is driven by the fact that the Navy is procuring
more than two-thirds of its 22 total radars prior to completing operational testing. Any
deficiencies the Navy discovers during at-sea testing could require revisions to existing
design drawings or retrofitting to already built radars, which would likely increase costs or
delay radar deliveries.
In order to support initial radar integration and testing with Aegis beginning in 2020, the
Navy plans to install production radar components at the Aegis combat system land-based
test site in New Jersey. Program officials said this is the first opportunity for AMDR and
Aegis contractors to integrate the systems to test interfaces and software compatibility. The
land-based tests will inform software development and integration of AMDR and Aegis in
support of ALO on the lead DDG 51 Flight III ship in 2022.
AMDR is well into low-rate initial production but has yet to demonstrate statistical control
of its critical manufacturing processes—an approach inconsistent with acquisition best
practices. In December 2019, the program exercised contract options that brought the
number of low-rate production units purchased to nine. However, the contractor continues
to experience cost and schedule growth on production radars due to issues with its Digital
Receiver Exciter (DREX)—a critical technology—and price variances on component
materials, which could affect the program’s procurement cost estimate if issues are not
resolved. Officials said a DREX subcomponent does not meet its vibration specifications,

14 Government Accountability Office, Defense Acquisitions Annual Assessment[:] Drive to Deliver Capabilities Faster
Increases Importance of Program Knowledge and Consistent Data for Oversight
, GAO-20-439, June 2020 p. 145.
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despite a recent contractor redesign. The program is exploring multiple mitigation options.
The contractor reported that these issues have delayed delivery of the first radar to at least
August 2020, 4 months later than the contract’s delivery date. Program officials said they
could mitigate the issue by delivering the radar to the ship without the DREX unit and
installing the unit later with minimal impact to the schedule. However, delays have already
consumed schedule margin and may threaten the first DDG 51 Flight III installation in
2020 as well as AMDR/DDG 51 Flight III operational testing in 2023.
Software and Cybersecurity
AMDR has completed six of its nine software deliveries to support core radar capabilities,
but additional development remains to add capabilities, integrate cybersecurity measures,
and integrate AMDR with Aegis. Software is incrementally released every 4 months for
testing before the final build is delivered to the end user every 10-12 months. Program
officials said this aligns with Aegis software development, which is being developed
concurrently. AMDR and Aegis software development will continue through 2021 while
both systems integrate and test software.
The Navy has conducted some initial cybersecurity testing with AMDR but will not fully
test cybersecurity capabilities with Aegis until at least 2023. However, the program reports
some cost growth due to implementing cybersecurity controls. If cybersecurity issues arise
during testing, additional software development may cause further cost growth or disrupt
operational testing.
Other Program Issues
The program is developing an Advanced Distributed Radar (ADR) capability that leverages
existing Navy technologies. The ADR capability increased the program’s cost estimate,
and the Navy projects it will require additional development funds through 2027. ADR is
expected to improve AMDR capability through radar enhancements. ADR will be
integrated on existing AMDR systems through software upgrades. The Navy plans to
finalize ADR requirements and begin development in 2020. Full ADR capability will not
be fielded until after the first AMDR-equipped DDG 51 Flight III is fielded in 2024.
Program Office Comments
We provided a draft of this assessment to the program office for review and comment. The
program office provided technical comments, which we incorporated where appropriate. It
stated that AMDR design is stable but software deficiencies might be discovered during
testing; AMDR’s demonstrated performance exceeded its performance thresholds during
land-based testing; and initial radar and Aegis integration began in 2016 and is on track to
support ALO and operational testing. The program office also said the contract type for the
low-rate initial production units minimizes the impact of component price variances and
some radar components have been delivered to support DDG 51 Flight III construction
schedules. According to the program office, initial cybersecurity updates are on track to
complete in 2021.15
Legislative Activity for FY2022
The Navy’s proposed FY2022 budget will be submitted to Congress later this year.

15 Government Accountability Office, Weapon Systems Annual Assessment[:] Limited Use of Knowledge-Based
Practices Continues to Undercut DOD’s Investments
, GAO-20-439, June 2020, p. 116.
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Legislative Activity for FY2021
Summary of Congressional Action on FY2021 Funding Request
Table 1
summarizes congressional action on the Navy’s FY2021 procurement funding requests
for the DDG-51 and DDG-1000 programs.
Table 1. Congressional Action on FY2021 Funding Request
Millions of dollars, rounded to nearest tenth
Authorization
Appropriation

Request
HASC
SASC
Conf.
HAC
SAC
Conf.
DDG-51 procurement
3,040.3
3,040.3
3,010.3
3,010.3
2,931.2
3,255.3
3,219.8
DDG-51 advance procurement (AP)
29.3
29.3
464.3
334.3
29.3
159.3
159.3
DDG-51 cost to complete
9.6
9.6
9.6
9.6
9.6
9.6
9.6
DDG-1000 procurement
78.2
78.2
78.2
78.2
78.2
78.2
78.2
Source: Table prepared by CRS based on Navy’s FY2021 budget submission, committee and conference
reports, and explanatory statements on FY2021 National Defense Authorization Act and FY2021 DOD
Appropriations Act.
Notes: 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.
FY2021 National Defense Authorization Act (H.R. 6395/S. 4049/P.L.
116-283)

House
The House Armed Services Committee, in its report (H.Rept. 116-442 of July 9, 2020) on H.R.
6395, recommended the funding levels shown in the HASC column of Table 1.
H.Rept. 116-442 states:
DDG–51 multiyear procurement
The committee continues to support the 355-ship fleet codified in the National Defense
Authorization Act for Fiscal Year 2018 (P.L. 116-115–91) as an essential part of the
National Defense Strategy and its emphasis on near-peer competitors such as Russia and
China. DDG–51 destroyers are the backbone of the surface fleet, providing multi-mission
flexibility and increasing capability with the introduction of Flight III and the AN/SPY–6
radar. With plans for the future Large Surface Combatant toward the end of this decade,
and the current multiyear procurement of DDG–51s running through fiscal year 2022, it is
imperative that another 10-ship multiyear contract is awarded for fiscal year 2023 to ensure
that Flight III capability will be available to the fleet. Such efforts will further strengthen
the defense industrial base, maximize savings, and provide the shipyards a clear projection
of work. Therefore, the committee encourages the Secretary of Defense and the Secretary
of the Navy to make all necessary steps that will allow for another multiyear contract for
DDG–51 Flight IIIs beginning in fiscal year 2023. (Page 17)
H.Rept. 116-442 also states:
National Surface Warship Engineering and Design Capability
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The Committee notes the President’s Fiscal Year 2021 Budget does not forecast funding
for any new surface shipbuilding programs throughout the Future Years’ Defense Plan
(FYDP). The Committee is aware of testimony from senior naval officials suggesting that
the DDG–51 Flight III design is effectively complete and that the ship will continue its
procurement throughout the FYDP, with a potential additional multiyear procurement for
DDG Flight III beginning in fiscal year 2023. The Committee also recognizes that when
the detailed design for FFG(X) is completed in 2022, there will be no active national
surface combatant engineering and design efforts underway that will allow for the
preservation of this critical and strategic domestic defense capability.
The design and development talent needed to create and sustain surface warship programs,
like the DDG–51 and its successors, requires unique and increasingly scarce maritime
systems and technological expertise. In the rapidly evolving threat environment, engineers
and designers must also support the essential integration of complex next generation
technologies such as autonomous and unmanned vehicles, hypersonic missiles, directed
energy weapons, larger radars and other vital technologies.
The Committee believes this engineering and design capability must be maintained in order
to produce the Large Surface Combatant, Next Generation Amphibious warship, and
potential unmanned surface vessels across the shipbuilding industrial base. Moreover, the
Committee believes that the challenges confronting future surface ship combatants such as
production and operations costs, energy management, and the flexibility to accommodate
current and evolving technologies are addressable via a robust and properly sequenced
engineering and design activity. The Committee notes similar actions have been
successfully taken to ensure the health of the nuclear engineering and design industrial base
with positive results that enabled the next generation of nuclear-powered aircraft carriers
and submarines to be designed and produced efficiently.
Therefore, not later than 180 days after enactment, the Committee directs the Secretary of
the Navy to assess the current and future workloads of the surface ship engineering and
design industrial base and provide recommendations for the sustainment of this critical
national capability. Such recommendations should be informed by both the current
program of record but should also include industry’s perspective on how to best fortify and
retain the capability and capacity resident in several locations nationwide. (Page 18)
H.Rept. 116-442 also states:
Variable Depth Sonar for DDG–51 destroyers
The committee recognizes and supports the Navy’s efforts to leverage mature technologies
and systems for the DDG–51 and small surface combatant programs. The committee
continues to encourage the Secretary of the Navy to emphasize commonality across Navy
platforms, commonality with existing platform equipment, and reduced acquisition and
lifecycle and sustainment costs in developing a best value solution for the platform.
However, the committee also believes it is critical that the Navy increase technical
capabilities, particularly in the area of anti-submarine warfare (ASW). Given ongoing
efforts by adversarial nations to increase the capability, lethality, and size of their
respective submarine fleets, the committee recognizes the critical role the DDG–51 and
small surface combatants will play in performing ASW missions around the globe. As such,
it is imperative that the platform be deployed with the most capable ASW technology
available.
Therefore, the committee directs the Secretary of the Navy to provide a briefing to the
House Committee on Armed Services not later than February 1, 2021, on the feasibility of
backfitting the AN/SQS–62 Variable Depth Sonar system on surface combatants. The
briefing shall include:
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(a) an explanation of the current DDG–51 ASW performance capabilities, including any
plans for ensuring the DDG–51s are part of a broader implementation of low-frequency
active capabilities aboard tactical surface ships;
(b) an analysis of commonality with program of record ASW systems, particularly those
recently developed as part of the littoral combat ship ASW Mission Package, to include
common hardware, spares, training, and logistics;
(c) an acquisition plan, including schedule, for AN/SQS–62 backfit into DDG–51s;
(d) the program schedule to fully incorporate AN/SQS–62 into the ASW mission packages
associated with the littoral combat ship; and
(e) an assessment of options to forward fit AN/SQS–62 into frigate. (Pages 20-21)
Senate (Committee Report)
The Senate Armed Services Committee, in its report (S.Rept. 116-236 of June 24, 2020) on S.
4049, recommended the funding levels shown in the SASC column of Table 1. The
recommended reduction of $30.0 million in DDG-51 procurement funding is for “Available prior-
year funds.” The recommended increase of $435.0 million in DDG-51 advance procurement (AP)
funding is for “LLTM [long leadtime material] for FY[20]22 DDG–51s” ($260.0 million) and
“Surface ship supplier stability” ($175.0 million). (Page 458) Regarding the recommended
changes from requested funding levels, S.Rept. 116-236 states:
Arleigh Burke-class destroyers
The budget request included $3.0 billion in line number 10 of Shipbuilding and
Conversion, Navy (SCN), for procurement of Arleigh Burke-class destroyers.
The committee notes the available prior year funds in this line number.
Therefore, the committee recommends a decrease of $30.0 million in line number 10 of
SCN.
Surface ship supplier stability
The budget request included $29.3 million in line number 11 of Shipbuilding and
Conversion, Navy (SCN), for DDG–51 advance procurement.
The committee believes that expanding the capabilities of the second- and third-tier
contractors in the surface ship industrial base should lead to greater industrial base stability,
cost savings, and improved efficiency as production increases to build greater quantities of
surface combatants.
The committee also notes that the Navy future years defense program includes procurement
of two Arleigh Burke-class destroyers in fiscal year 2022, which would be procured using
a multiyear procurement contract. The committee understands that advance procurement
of long lead time material could reduce component costs and enable improved ship
construction intervals.
Therefore, the committee recommends an increase of $435.0 million in line number 11 for
DDG–51 advance procurement.
The committee directs the Secretary of the Navy to notify the congressional defense
committees, in writing, within 30 days of obligating funds provided for surface ship
supplier stability. The notification shall include: obligation date, contractor name or names,
location, description of the shortfall to be addressed, actions to be undertaken, desired end
state, usable end items to be procured, period of performance, dollar amount, projected
associated savings, including business case analysis, if applicable, contract name, and
contract number. (Page 31)
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Section 1025 of S. 4049 as reported by the committee states (emphasis added):
SEC. 1025. SENSE OF CONGRESS ON ACTIONS NECESSARY TO ACHIEVE A 355-
SHIP NAVY.
It is the sense of Congress that to achieve the national policy of the United States to have
available, as soon as practicable, not fewer than 355 battle force ships—
(1) the Navy must be adequately resourced to increase the size of the Navy in accordance
with the national policy, which includes the associated ships, aircraft, personnel,
sustainment, and munitions;
(2) across fiscal years 2021 through 2025, the Navy should start construction on not
fewer than

(A) 12 Arleigh Burke-class destroyers;
(B) 10 Virginia-class submarines;
(C) 2 Columbia-class submarines;
(D) 3 San Antonio-class amphibious ships;
(E) 1 LHA-class amphibious ship;
(F) 6 John Lewis-class fleet oilers; and
(G) 5 guided missile frigates;
(3) new guided missile frigate construction should increase to a rate of between two and
four ships per year once design maturity and construction readiness permit;
(4) the Columbia-class submarine program should be funded with additions to the Navy
budget significantly above the historical average, given the critical single national mission
that these vessels will perform and the high priority of the shipbuilding budget for
implementing the National Defense Strategy;
(5) stable shipbuilding rates of construction should be maintained for each vessel class,
utilizing multi-year or block buy contract authorities when appropriate, until a deliberate
transition plan is identified; and
(6) prototyping of potential new shipboard sub systems should be accelerated to build
knowledge systematically, and, to the maximum extent practicable, shipbuilding
prototyping should occur at the subsystem-level in advance of ship design.
S.Rept. 116-236 also states:
DDG–51 destroyer multi-year procurement
The committee continues to support the national policy of achieving at least a 355-ship
fleet, as codified in the National Defense Authorization Act for Fiscal Year 2018 (P.L. 116-
115–91), which is integral to the National Defense Strategy and its emphasis on near-peer
competition with Russia and China.
The committee views DDG–51 destroyers as the backbone of the surface fleet, providing
multi-mission flexibility and increasing capability with introduction of Flight III and the
AN/SPY–6 radar.
With plans for construction of a new class of Large Surface Combatants (LSCs) toward the
end of this decade and the current multi-year procurement of DDG–51s ending in fiscal
year 2022, the committee believes that it is imperative that the Navy award another DDG–
51 multi-year contract beginning in fiscal year 2023.
This contract is critical to ensuring that Flight III capability continues to be delivered to
the fleet and the industrial base is maintained to support the LSC acquisition strategy.
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Accordingly, the committee urges the Secretary of Defense and the Secretary of the Navy
to make all necessary plans to award another multi-year contract for DDG–51 Flight III
destroyers in fiscal year 2023, including long lead material purchases in fiscal year 2022.
(Page 49)
S.Rept 116-236 also states the following regarding the Future Surface Combatant (FSC), also
known as the Large Surface Combatant (LSC), which is a next-generation cruiser- or destroyer-
like ship that the Navy wants to begin procuring around FY2028 as the successor to the DDG-51
Flight III design (emphasis added):
Ship concept advanced design
The budget request included $21.5 billion in Research, Development, Test, and Evaluation
(RDT&E), Navy, of which $126.4 million was for PE 63563N ship concept advanced
design.
The committee lacks sufficient clarity on the capability requirements to support the
following ship design efforts: Future Surface Combatant (project 2196, $19.1 million),
next generation medium amphibious ship (project 4044, $30.0 million), and next
generation medium logistics ship (project 4045, $30.0 million).
The committee supports the Conditions Based Maintenance + (CBM+) initiative, which
improves the cost, schedule, and performance outcomes in ship maintenance availabilities
using analytic tools. The committee understands that additional funds ($16.0 million) could
accelerate the implementation of the CBM+ initiative. Accordingly, the committee
recommends a decrease of $63.1 million, for a total of $63.3 million, in RDT&E, Navy,
for PE 63563N.
Large Surface Combatant preliminary design
The budget request included $21.5 billion in Research, Development, Test, and Evaluation
(RDT&E), Navy, of which $70.2 million was for PE 63564N ship preliminary design and
feasibility studies.
The committee lacks sufficient clarity on the Large Surface Combatant (LSC) capability
requirements and the program’s compliance with section 131 of the National Defense
Authorization Act for Fiscal Year 2020 (Public Law 116–92) to support the start of
preliminary design for the LSC program or completion of the Capabilities Development
Document (project 0411).
Accordingly, the committee recommends a decrease of $41.3 million, for a total of $29.0
million, in RDT&E, Navy, for PE 63564N. Additionally, the committee directs the
Secretary of the Navy to submit a report with Navy’s fiscal year 2022 budget request that
details the plan to comply with the requirements of section 131 of the National Defense
Authorization Act for Fiscal Year 2020. (Pages 98-99)
Senate (Floor Consideration)
On June 29, 2020, the chairman of the Senate Armed Services Committee, Senator Inhofe,
proposed Senate Amendment 2301, an amendment in the nature of a substitute. This amendment
would, among other things, amend S. 4049 to add Section 5121, which states:
SEC. 5121. LIMITATION ON ALTERATION OF NAVY FLEET MIX.
(a) Sense of Congress.--It is the sense of Congress that--
(1) the United States shipbuilding and supporting vendor base constitute a national security
imperative that is unique and must be protected;
(2) a healthy and efficient industrial base continues to be a fundamental driver for achieving
and sustaining a successful shipbuilding procurement strategy;
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(3) without consistent and continuous commitment to steady and predictable acquisition
profiles, the industrial base will struggle and some elements may not survive; and
(4) proposed reductions in the future-years defense program to the DDG-51 Destroyer
procurement profile without a clear transition to procurement of the next Large Surface
Combatant would adversely affect the shipbuilding industrial base and long-term strategic
objectives of the Navy.
(b) Limitation.--
(1) In general.--The Secretary of the Navy may not deviate from the 2016 Navy Force
Structure Assessment to implement the results of a new force structure assessment or new
annual long-range plan for construction of naval vessels that would reduce the requirement
for Large Surface Combatants to fewer than 104 such vessels until the date on which the
Secretary of the Navy submits to the congressional defense committees the certification
under paragraph (2) and the report under subsection (c).
(2) Certification.--The certification referred to in paragraph (1) is a certification, in
writing, that each of the following conditions have been satisfied:
(A) The large surface combatant shipbuilding industrial base and supporting vendor base
would not significantly deteriorate due to a reduced procurement profile.
(B) The Navy can mitigate the reduction in anti-air and ballistic missile defense capabilities
due to having a reduced number of DDG-51 Destroyers with the advanced AN/SPY-6 radar
in the next three decades.
(c) Report.--Not later than 90 days after the date of the enactment of this Act, the Secretary
of the Navy shall submit to the congressional defense committees a report that includes--
(1) a description of likely detrimental impacts to the large surface combatant industrial base
and the Navy's plan to mitigate any such impacts if the fiscal year 2021 future-years defense
program were implemented as proposed;
(2) a review of the benefits to the Navy fleet of the new AN/SPY-6 radar to be deployed
aboard Flight III variant DDG-51 Destroyers, which are currently under construction, as
well as an analysis of impacts to the fleet's warfighting capabilities, should the number of
such destroyers be reduced; and
(3) a plan to fully implement section 131 of the National Defense Authorization for Fiscal
Year 2020 (P.L. 116-92), including subsystem prototyping efforts and funding by fiscal
year.
Conference
The conference report (H.Rept. 116-617 of December 3, 2020) on H.R. 6395/P.L. 116-283 of
January 1, 2021, recommends the funding levels shown in the authorization conference column of
Table 1. The recommended reduction of $30.0 million for DDG-51 procurement is for “Available
prior-year funds.” The recommended increase of $305.0 million for DDG-51 advance
procurement (AP) is for “LLTM [long leadtime materials] for FY22 DDG–51s” ($130.0 million)
and “Surface ship supplier stability” ($175.0 million). (PDF page 4276 of 4517)
Section 121 of the conference version of H.R. 6395 states:
SEC. 121. LIMITATION ON ALTERATION OF THE NAVY FLEET MIX.
(a) LIMITATION.—
(1) IN GENERAL.—The Secretary of the Navy may not deviate from the large surface
combatant requirements included in the 2016 Navy Force Structure Assessment until the
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date on which the Secretary submits to the congressional defense committees the
certification under paragraph (2) and the report under subsection (b).
(2) CERTIFICATION.—The certification referred to in paragraph (1) is a certification, in
writing, that the Navy can mitigate the reduction in multi-mission large surface combatant
requirements, including anti-air and ballistic missile defense capabilities, due to having a
reduced number of DDG–51 Destroyers with the advanced AN/SPY–6 radar in the next
three decades.
(b) REPORT.—Not later than 90 days after the date of the enactment of this Act, the
Secretary of the Navy shall submit to the congressional defense committees a report that
includes—
(1) a description of likely detrimental impacts to the large surface combatant industrial
base, and a plan to mitigate such impacts, if the fiscal year 2021 future-years defense
program is implemented as proposed;
(2) a review of the benefits to the Navy fleet of the new AN/SPY–6 radar to be deployed
aboard Flight III variant DDG–51 Destroyers, which are currently under construction, as
well as an analysis of impacts to the warfighting capabilities of the fleet should the number
of such destroyers be reduced; and
(3) a plan to fully implement section 131 of the National Defense Authorization for Fiscal
Year 2020 (Public Law 116–92; 133 Stat. 1237), including subsystem prototyping efforts
and funding by fiscal year.
Regarding Section 121, H.Rept. 116-617 states:
Limitation on alteration of the Navy fleet mix (sec. 121)
The Senate amendment contained a provision (sec. 5121) that would express the sense of
Congress on the importance of the Navy shipbuilding industrial base, limit deviations to
the Navy’s 2016 requirement for large surface combatants, and require a report on large
surface combatants.
The House bill contained no similar provision.
The House recedes with an amendment that would remove the sense of Congress and
modify the limitation on deviations to the Navy’s 2016 requirement for large surface
combatants.
The conferees believe that prototyping critical subsystems is essential to maturing new
technologies and reducing technical risks for lead ships in new classes of naval vessels.
The conferees understand Navy officials are considering design changes to the Zumwalt-
class of destroyers to increase the combat capability, potentially including the integration
of a different missile launcher, radar, and combat system. The conferees view these
potential changes to the Zumwalt-class as opportunities to mature technology and reduce
technical and integration risks for the next Large Surface Combatant class of vessels, as
required by section 131(a)(2) of the National Defense Authorization Act for Fiscal Year
2020 (Public Law 116-92), while also providing more capable Zumwalt-class destroyers
to fleet commanders.
Accordingly, the conferees direct the Secretary of the Navy to submit to the congressional
defense committees not later than March 1, 2021, a report on potential Zumwalt-class
capability upgrades. This report shall include:
(1) Navy plans or options under review to upgrade Zumwalt-class destroyers, including,
but not limited to, missile launchers, radars, and combat systems;
(2) The extent to which the plans or options under review identified in paragraph (1) could
provide opportunities to mature technology and reduce technical and integration risks for
the next Large Surface Combatant class of vessels;
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(3) The extent to which the plans or options under review identified in paragraph (1) are
included in the Navy’s plans to comply with section 131 of the National Defense
Authorization Act for Fiscal Year 2020 (Public Law 116-92); and
(4) Any related matters the Secretary deems appropriate. (PDF pages 3729-3730 of 4517)
H.Rept. 116-617 also states:
Sense of Congress on actions necessary to achieve a 355-ship Navy
The Senate amendment contained a provision (sec. 1025) that would express the sense of
Congress on actions necessary to implement the national policy of the United States to
have available, as soon as practicable, not fewer than 355 battle force ships.
The House bill contained no similar provision.
The Senate recedes. (PDF page 4024 of 4517)
FY2021 DOD Appropriations Act (H.R. 7617/S. XXXX/Division C of
H.R. 133/P.L. 116-260)

House
The House Appropriations Committee, in its report (H.Rept. 116-453 of July 16, 2020) on H.R.
7617, recommended the funding levels shown in the HAC column of Table 1. The recommended
reduction of $109.025 million for DDG-51 procurement is for “Excess funds.” (Page 184)
H.Rept. 116-453 states:
DDG–51 MULTI YEAR PROCUREMENT
The Committee continues to support the Navy’s stated goal of a 355-ship fleet, which is an
essential part of the National Defense Strategy and its emphasis on near-peer competitors.
The Committee recognizes that DDG–51 Destroyers are the backbone of the surface fleet,
providing multi-mission flexibility and increasing capability with the introduction of the
Flight III variant. The Committee understands the Navy has plans to develop and procure
a future Large Surface Combatant in the near future, and notes that the current multi-year
procurement of DDG–51s will end in fiscal year 2022. The Committee believes that a
follow-on DDG–51 multiyear procurement contract awarded for fiscal year 2023 will
ensure that Flight III capability will be available to the fleet and the domestic industrial
base will be sustained until the award of the Large Surface Combatant contract. The
Committee encourages the Secretary of the Navy to review the potential benefits of
awarding a multi-year contract for DDG–51 Flight IIIs in fiscal year 2023. (Page 185)
Senate
The Senate Appropriations Committee, in the explanatory statement for S. XXXX that the
committee released on November 10, 2020, recommended the funding levels shown in the SAC
column of Table 1. The recommended increase of $215.0 million for DDG-51 procurement is for
“Program increase: Surface combatant shipyard infrastructure,” and the recommended increase of
$130.0 million for DDG-51 advance procurement (AP) is for “Program increase: Long lead time
material only for 3rd DDG–51 in fiscal year 2022.” (Page 114)
The explanatory statement for the bill released by the committee on November 10, 2020, states:
DDG–51 Flight III Acquisition Strategy.—The Committee notes that the current multi-
year procurement contract for the DDG–51 Flight III destroyer ends in fiscal year 2022,
and that with submission of the fiscal year 2021 President’s budget request the Navy further
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delayed the detailed design and construction schedule of the planned follow-on program,
the future Large Surface Combatant [LSC], until no sooner than fiscal year 2026. The
Committee notes that despite this delay to LSC, the Navy is planning to procure only four
DDG–51 Flight III destroyers from fiscal years 2023–2025, well below the current 2.4
DDG–51 destroyers per year MYP acquisition, and that the Navy in each of the last two
budget submissions has reduced the procurement profile for DDG–51 Flight III destroyers.
The Committee finds this inconsistent with previously stated shipbuilding objectives and
believes that the lack of a predictable and stable acquisition strategy for large surface
combatants undercuts naval maritime superiority and injects risk into the industrial base.
The Assistant Secretary of the Navy (Research, Development and Acquisition) is directed
to provide to the congressional defense committees, with submission of the fiscal year 2022
President’s budget request, the Navy’s fully funded strategy for large surface combatants.
The Committee recommends an additional $130,000,000 in advance procurement only for
an additional DDG–51 Flight III destroyer in fiscal year 2022. (Page 117)
Conference
The explanatory statement for the final version of the FY2021 DOD Appropriations Act (Division
C of H.R. 133/P.L. 116-260 of December 27, 2020, the Consolidated Appropriations Act, 2021)
provides the funding levels shown in the appropriation conference column of Table 1. The net
increase of $179.573 million for DDG-51 procurement includes a reduction of $35.427 million
for “Excess funds” and an increase of $215.0 million for “Program increase—surface combatant
shipyard infrastructure.” The increase of $130.0 million for DDG-51 advance procurement (AP)
is for “Program increase—long lead time material only for third DDG-51 in fiscal year 2022.”
(PDF page 204 of 469)
The explanatory statement for Division C of H.R. 133 states:
DDG-51 FLIGHT III ACQUISITION STRATEGY
It is noted that the current multi-year procurement (MYP) contract for the DDG-51 Flight
III destroyer ends in fiscal year 2022 and that with the submission of the fiscal year 2021
President’s budget request the Navy further delayed the detailed design and construction
schedule of the planned follow-on program, the future Large Surface Combatant (LSC),
until no earlier than fiscal year 2026. It is further noted that despite this delay to LSC, the
Navy is planning to procure only four DDG-51 Flight III destroyers from fiscal years 2023
to 2025, well below the current 2.4 DDG-51 destroyers per year MYP acquisition, and that
in each of the last two budget submissions the Navy has reduced the procurement profile
for DDG-51 Flight III destroyers. This is inconsistent with previously stated shipbuilding
objectives, and the lack of a predictable and stable acquisition strategy for large surface
combatants undercuts naval maritime superiority and injects risk into the industrial base.
The Assistant Secretary of the Navy (Research, Development and Acquisition) is directed
to provide to the congressional defense committees, with submission of the fiscal year 2022
President's budget request, the Navy's fully funded strategy for large surface combatants.
The agreement recommends an additional $130,000,000 in advance procurement only for
an additional DDG-51 Flight III destroyer in fiscal year 2022. (PDF pages 209-210 of 469)
The explanatory statement for Division C of H.R. 133 also states:
FUTURE SURFACE COMBATANT FORCE
The fiscal year 2021 President’s budget request includes $46,453,000 in program element
0603564N for requirements development, prototyping, and preliminary contract design of
a new Large Surface Combatant (LSC) class to succeed the current DDG-51 Flight III
destroyer. Additionally, $19,020,000 is included in program element 0603563N for
requirements and concept analysis of an LSC. Despite repeated delays to the LSC program,
the Navy has reduced the acquisition profile for DDG-51 Flight III destroyers in recent
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budget submissions, and has not delineated a clear acquisition path for large surface
combatants following the conclusion of the current DDG-51 Flight III destroyer multi-year
procurement contract in fiscal year 2022. Absent a clear understanding of future Navy LSC
force structure requirements and acquisition strategies, the proposed increase in funding
for LSC, to include $17,100,000 in preliminary design efforts, is not supported.
Further, it is noted that information provided by the Navy in response to Senate Report
116-103 regarding the Navy's Surface Capability Evolution Plan (SCEP) was incomplete.
The Assistant Secretary of the Navy (Research, Development and Acquisition) is directed
to provide to the congressional defense committees, with the fiscal year 2022 President's
budget request, the updated acquisition strategies for each element of the Navy's SCEP, as
previously requested, and the Assistant Secretary of the Navy (Financial Management and
Comptroller) is directed to provide, with the fiscal year 2022 President's budget request,
updated cost estimates for each element of the SCEP, and to certify full funding in the
budget request for each respective acquisition strategy of the SCEP elements. (PDF pages
322-323 of 469)


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Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress

Appendix. Additional Background Information on
DDG-1000 Program
This appendix presents additional background information on the DDG-1000 program.
Overview
The DDG-1000 program was initiated in the early 1990s.16 DDG-1000s (Figure A-1) are multi-
mission destroyers with an originally intended emphasis on naval surface fire support (NSFS) and
operations in littoral (i.e., near-shore) waters. (NSFS is the use of naval guns to provide fire
support for friendly forces operating ashore.)
Figure A-1. DDG-1000 Class Destroyer

Source: U.S. Navy photo 151207-N-ZZ999-435, posted December 8, 2015, with a caption that reads in part:
“The future USS Zumwalt (DDG 1000) is underway for the first time conducting at-sea tests and trials in the
Atlantic Ocean Dec. 7, 2015.”
DDG-1000s were originally intended to replace, in a technologically more modern form, the
large-caliber naval gun fire capability that the Navy lost when it retired its Iowa-class battleships
in the early 1990s,17 to improve the Navy’s general capabilities for operating in defended littoral

16 The program was originally designated DD-21, which meant destroyer for the 21st century. In November 2001, the
program was restructured and renamed DD(X), meaning a destroyer whose design was in development. In April 2006,
the program’s name was changed again, to DDG-1000, meaning a guided missile destroyer with the hull number 1000.
17 The Navy in the 1980s reactivated and modernized four Iowa (BB-61) class battleships that were originally built
during World War II. The ships reentered service between 1982 and 1988 and were removed from service between
1990 and 1992.
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waters, and to introduce several new technologies that would be available for use on future Navy
ships. The DDG-1000 was also intended to serve as the basis for a planned cruiser called CG(X)
that was subsequently canceled.18
DDG-1000s are to have reduced-size crews of 175 sailors (147 to operate the ship, plus a 28-
person aviation detachment), compared to roughly 300 on the Navy’s Aegis destroyers and
cruisers, so as to reduce its operating and support (O&S) costs. The DDG-1000 design
incorporates a significant number of new technologies, including an integrated electric-drive
propulsion system19 and automation technologies enabling its reduced-sized crew.
With an estimated full load displacement of 15,656 tons, the DDG-1000 design is substantially
larger than the Navy’s Aegis cruisers and destroyers, which have displacements of up to about
9,700 tons, and are larger than any Navy destroyer or cruiser since the nuclear-powered cruiser
Long Beach (CGN-9), which was procured in FY1957.
The first two DDG-1000s were procured in FY2007 and split-funded (i.e., funded with two-year
incremental funding) in FY2007-FY2008; the Navy’s FY2021 budget submission estimates their
combined procurement cost at $9,409.2 million. The third DDG-1000 was procured in FY2009
and split-funded in FY2009-FY2010; the Navy’s FY2021 budget submission estimates its
procurement cost at $3,866.4 million.
The first DDG-1000 was commissioned into service on September 7, 2016. Its delivery date was
revised multiple times. In the Navy’s FY2021 budget submission, the ship’s delivery date was
revised to March 2020. The ship’s actual delivery date reportedly was April 2020.20 This created
an unusual situation in which a ship was commissioned into service more than three years prior to
its delivery date.
The delivery dates for the second and third ships have also been revised multiple times.21 In the
Navy’s FY2021 budget submission, the delivery dates for the two ships were revised to
September 2020 and September 2022, respectively. In January 2021, it was reported that the
delivery date of the second ship had been delayed from September 2020 to sometime in
FY2022.22

18 For more on the CG(X) program, see CRS Report RL34179, Navy CG(X) Cruiser Program: Background for
Congress
, by Ronald O'Rourke.
19 For more on integrated electric-drive technology, see CRS Report RL30622, Electric-Drive Propulsion for U.S. Navy
Ships: Background and Issues for Congress
, by Ronald O'Rourke.
20 See Aidan Quigley, “Final Delivery of Zumwalt-class Destroyer Monsoor Delayed,” Inside Defense, January 21,
2021.
21 The revised delivery dates for the three ships reflect Section 121 of the FY2017 National Defense Authorization Act
(S. 2943/P.L. 114-328 of December 23, 2016), a provision that establishes standards for determining vessel delivery
dates and which also required the Secretary of the Navy to certify that the delivery dates for certain ships, including the
three DDG-1000s, had been adjusted in accordance with the provision. The Navy’s original plan for the DDG-1000
program was to install certain elements of each DDG-1000’s combat system after delivering the ship and
commissioning it into service. Section 121 of P.L. 114-328 in effect requires the Navy to defer the delivery date of a
DDG-1000 until those elements of the combat system are installed. By the time P.L. 114-328 was enacted, DDG-1000,
per the Navy’s original plan, had already been commissioned into service without those elements of its combat system.
22 See Aidan Quigley, “Final Delivery of Zumwalt-class Destroyer Monsoor Delayed,” Inside Defense, January 21,
2021.
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Program Origin
The program known today as the DDG-1000 program was announced on November 1, 2001,
when the Navy stated that it was replacing a destroyer-development effort called the DD-21
program, which the Navy had initiated in the mid-1990s, with a new Future Surface Combatant
Program aimed at developing and acquiring a family of three new classes of surface
combatants:23
a destroyer called DD(X) for the precision long-range strike and naval gunfire
mission;
a cruiser called CG(X) for the air defense and ballistic missile mission; and
a smaller combatant called the Littoral Combat Ship (LCS) to counter
submarines, small surface attack craft (also called “swarm boats”), and mines in
heavily contested littoral (near-shore) areas.24
On April 7, 2006, the Navy announced that it had redesignated the DD(X) program as the DDG-
1000 program. The Navy also confirmed in that announcement that the first ship in the class,
DDG-1000, would be named Zumwalt, in honor of Admiral Elmo R. Zumwalt, the Chief of Naval
operations from 1970 to 1974. The decision to name the first ship after Zumwalt was made by the
Clinton Administration in July 2000, when the program was still called the DD-21 program.25
New Technologies
The DDG-1000 incorporates a significant number of new technologies, including a wave-
piercing, tumblehome hull design for reduced detectability,26 a superstructure on the first two
ships, but not the third that is made partly of large sections of composite (i.e., fiberglass-like)
materials rather than steel or aluminum, an integrated electric-drive propulsion system,27 a total-
ship computing system for moving information about the ship, automation technologies enabling
its reduced-sized crew, a dual-band radar (that was later changed to a single-band radar), a new
kind of vertical launch system (VLS) for storing and firing missiles, and two copies of a new
155mm gun called the Advanced Gun System (AGS).

23 The DD-21 program was part of a Navy surface combatant acquisition effort begun in the mid-1990s and called the
SC-21 (Surface Combatant for the 21st Century) program. The SC-21 program envisaged a new destroyer called DD-21
and a new cruiser called CG-21. When the Navy announced the Future Surface Combatant Program in 2001,
development work on the DD-21 had been underway for several years, while the start of development work on the CG-
21 was still years in the future. The current DDG-1000 destroyer CG(X) cruiser programs can be viewed as the
descendants, respectively, of the DD-21 and CG-21. The acronym SC-21 is still used in the Navy’s research and
development account to designate the line item (i.e., program element) that funds development work on both the DDG-
1000 and CG(X).
24 For more on the LCS program, see CRS Report RL33741, Navy Littoral Combat Ship (LCS) Program: Background
and Issues for Congress
, by Ronald O'Rourke.
25 For more on Navy ship names, see CRS Report RS22478, Navy Ship Names: Background for Congress, by Ronald
O'Rourke.
26 A tumblehome hull slopes inward, toward the ship’s centerline, as it rises up from the waterline, in contrast to a
conventional flared hull, which slopes outward as it rises up from the waterline.
27 For more on integrated electric-drive technology, see CRS Report RL30622, Electric-Drive Propulsion for U.S. Navy
Ships: Background and Issues for Congress
, by Ronald O'Rourke.
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Shipbuilders and Combat System Prime Contractor
GD/BIW is the builder for all three DDG-1000s, with some portions of each ship being built by
HII/Ingalls for delivery to GD/BIW. Raytheon is the prime contractor for the DDG-1000’s
combat system (its collection of sensors, computers, related software, displays, and weapon
launchers).
Under a DDG-1000 acquisition strategy approved by the Under Secretary of Defense for
Acquisition, Technology, and Logistics (USD AT&L) on February 24, 2004, the first DDG-1000
was to have been built by HII/Ingalls, the second ship was to have been built by GD/BIW, and
contracts for building the first six were to have been equally divided between HII/Ingalls28 and
GD/BIW.
In February 2005, Navy officials announced that they would seek approval from USD AT&L to
instead hold a one-time, winner-take-all competition between HII/Ingalls and GD/BIW to build
all DDG-1000s. On April 20, 2005, the USD AT&L issued a decision memorandum deferring this
proposal, stating in part, “at this time, I consider it premature to change the shipbuilder portion of
the acquisition strategy which I approved on February 24, 2004.”
Several Members of Congress also expressed opposition to the Navy’s proposal for a winner-
take-all competition. Congress included a provision (§1019) in the Emergency Supplemental
Appropriations Act for 2005 (H.R. 1268/P.L. 109-13 of May 11, 2005) prohibiting a winner-take-
all competition. The provision effectively required the participation of at least one additional
shipyard in the program but did not specify the share of the program that is to go to the additional
shipyard.
On May 25, 2005, the Navy announced that, in light of Section 1019 of P.L. 109-13, it wanted to
shift to a “dual-lead-ship” acquisition strategy, under which two DDG-1000s would be procured
in FY2007, with one to be designed and built by HII/Ingalls and the other by GD/BIW.
Section 125 of the FY2006 defense authorization act (H.R. 1815/P.L. 109-163) again prohibited
the Navy from using a winner-take-all acquisition strategy for procuring its next-generation
destroyer. The provision again effectively requires the participation of at least one additional
shipyard in the program but does not specify the share of the program that is to go to the
additional shipyard.
On November 23, 2005, the USD AT&L granted Milestone B approval for the DDG-1000,
permitting the program to enter the System Development and Demonstration (SDD) phase. As
part of this decision, the USD AT&L approved the Navy’s proposed dual-lead-ship acquisition
strategy and a low rate initial production quantity of eight ships (one more than the Navy
subsequently planned to procure).
On February 14, 2008, the Navy awarded contract modifications to GD/BIW and HII/Ingalls for
the construction of the two lead ships. The awards were modifications to existing contracts that
the Navy has with GD/BIW and HII/Ingalls for detailed design and construction of the two lead
ships. Under the modified contracts, the line item for the construction of the dual lead ships is
treated as a cost plus incentive fee (CPIF) item.
Until July 2007, it was expected that HII/Ingalls would be the final-assembly yard for the first
DDG-1000 and that GD/BIW would be the final-assembly yard for the second. On September 25,

28 At the time of the events described in this section, HII was owned by Northrop Grumman and was called Northrop
Grumman Shipbuilding (NGSB).
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2007, the Navy announced that it had decided to build the first DDG-1000 at GD/BIW, and the
second at HII/Ingalls.
On January 12, 2009, it was reported that the Navy, HII/Ingalls, and GD/BIW in the fall of 2008
began holding discussions on the idea of having GD/BIW build both the first and second DDG-
1000s, in exchange for HII/Ingalls receiving a greater share of the new DDG-51s that would be
procured under the Navy’s July 2008 proposal to stop DDG-1000 procurement and restart DDG-
51 procurement.29
On April 8, 2009, it was reported that the Navy had reached an agreement with HII/Ingalls and
GD/BIW to shift the second DDG-1000 to GD/BIW, and to have GD/BIW build all three ships.
HII/Iingalls will continue to make certain parts of the three ships, notably their composite
deckhouses. The agreement to have all three DDG-1000s built at GD/BIW was a condition that
Secretary of Defense Robert Gates set forth in an April 6, 2009, news conference on the FY2010
defense budget for his support for continuing with the construction of all three DDG-1000s
(rather than proposing the cancellation of the second and third).
Reduction in Procurement to Three Ships
Navy plans for many years called for ending DDG-51 procurement in FY2005, to be followed by
procurement of up to 32 DDG-1000s and some number of CG(X)s. In subsequent years, the
planned total number of DDG-1000s was reduced to 16 to 24, then to 7, and finally to 3.
At the end of July 2008, in a major reversal of its destroyer procurement plans, the Navy
announced that it wanted to end procurement of DDG-1000s and resume procurement of DDG-
51s. In explaining this reversal, which came after two DDG-1000s had been procured, the Navy
stated that it had reevaluated the future operating environment and determined that its destroyer
procurement now needed to emphasize three missions: open-ocean antisubmarine warfare
(ASW), countering anti-ship cruise missiles (ASCMs), and countering ballistic missiles. Although
the DDG-1000 could perform the first two of these missions and could be modified to perform
the third, the Navy concluded that the DDG-51 design could perform these three missions
adequately and would be less expensive to procure than the DDG-1000 design.
The Navy’s proposal to stop procuring DDG-1000s and resume procuring DDG-51s was
presented in the Navy’s proposed FY2010 budget, which was submitted to Congress in 2009.
Congress, in acting on the Navy’s FY2010 budget, approved the idea of ending DDG-1000
procurement and restarting DDG-51 procurement, and procured a third DDG-1000 as the final
ship in the class.
In retrospect, the Navy’s 2008 reversal in its destroyer procurement plans can be viewed as an
early indication of the ending of the post-Cold War era (during which the Navy focused its
planning on operating in littoral waters against the land- and sea-based forces of countries such as
Iran and North Korea) and the shift in the international security environment to renewed great
power competition (during which the Navy is now focusing its planning more on being able to
operate in mid-ocean waters against capable naval forces from near-peer competitors such as
China and Russia).30

29 Christopher P. Cavas, “Will Bath Build Second DDG 1000?” Defense News, January 12, 2009: 1, 6.
30 For additional discussion, see CRS Report R43838, Renewed Great Power Competition: Implications for Defense—
Issues for Congress
, by Ronald O'Rourke, and CRS Report RL33153, China Naval Modernization: Implications for
U.S. Navy Capabilities—Background and Issues for Congress
, by Ronald O'Rourke.
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Increase in Estimated Procurement Cost
As shown in Table A-1 below, the estimated combined procurement cost for all three DDG-
1000s, as reflected in the Navy’s annual budget submission, has grown by $4,298.5 million, or
47.9%, since the FY2009 budget (i.e., the budget for the fiscal year in which the third DDG-1000
was procured).

Table A-1. Estimated Combined Procurement Cost of DDG-1000, DDG-1001, and
DDG-2002
In millions, rounded to nearest tenth, as shown in annual Navy budget submissions
Estimated combined
Change from prior
Cumulative change
Budget
procurement cost
year’s budget
from FY2009 budget
submission
(millions of dollars)
submission
submission
FY09
8,977.1


FY10
9,372.5
+395.4 (+4.4%)
+395.4 (+4.4%)
FY11
9,993.3
+620.8 (+6.6%)
+1,016.2 (+11.3%)
FY12
11,308.8
+1,315.5 (+13.2%)
+2,331.7 (+26.0%)
FY13
11,470.1
+161.3 (+1.4%)
+2,493.0 (+27.8%)
FY14
11,618.4
+148.3 (+1.3%)
+2,641.3 (+29.4%)
FY15
12,069.4
+451.0 (+3.9%)
+3,092.3 (+34.4%)
FY16
12,288.7
+219.3 (+1.8%)
+3,311.6 (+36.9%)
FY17
12,738.2
+449.5 (+3.7%)
+3,761.1 (+41.9%)
FY18
12,882.0
+143.8 (+1.1%)
+3,904.0 (+43.5%)
FY19
13,032.2
+150.2 (+1.2%)
+4,055.1 (+45.1%)
FY20
13,195.5
+163.3 (+1.3%)
+4,218.4 (+47.0%)
FY21
13,275.6
+80.1 (+ 0.6%)
+4,298.5 (+47.9%)
Source: Table prepared by CRS based on data in annual Navy budget submissions.
Some of the cost growth in the earlier years in the table was caused by the truncation of the DDG-
1000 program from seven ships to three, which caused some class-wide procurement-rated costs
that had been allocated to the fourth through seventh ships in the program to be reallocated to the
three remaining ships.
The Navy states that the cost growth shown through FY2015 in the table reflects, among other
things, a series of incremental, year-by-year movements away from an earlier Navy cost estimate
for the program, and toward a higher estimate developed by the Cost Assessment and Program
Evaluation (CAPE) office within the Office of the Secretary of Defense (OSD). As one
consequence of a Nunn-McCurdy cost breach experienced by the DDG-1000 program in 2010
(see discussion below), the Navy was directed to fund the DDG-1000 program to CAPE’s higher
cost estimate for the period FY2011-FY2015, and to the Navy’s cost estimate for FY2016 and
beyond. The Navy states that it implemented this directive in a year-by-year fashion with each
budget submission from FY2010 through FY2015, moving incrementally closer each year
through FY2015 to CAPE’s higher estimate. The Navy stated in 2014 that even with the cost
growth shown in the table, the DDG-1000 program as of the FY2015 budget submission was still
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about 3% below the program’s rebaselined starting point for calculating any new Nunn-McCurdy
cost breach on the program.31
Technical Risk and Test and Evaluation Issues
June 2020 GAO Report
A June 2020 GAO report assessing selected major DOD weapon acquisition programs stated the
following of the DDG-1000 program:
Technology Maturity, Design Stability, and Production Readiness
The DDG 1000 program has fully matured most, but not all, of its nine original current
critical technologies and reports a stable design. According to the Navy, the vertical launch
system, infrared signature, and total ship computing environment are each continuing to
approach maturity. The Navy expects to fully mature these systems as it completes ship
construction, certification, and testing over the next 2 years. In addition to these nine
technologies, the Navy has now added three critical technologies to meet its new mission:
a communication system, an intelligence system, and the seeker on an offensive strike
missile. These technologies are planned to be mature when they are integrated onto the
ship, but this integration will not occur until several years after the ship undergoes testing.
The Navy plans to complete operational testing of the lead ship in September 2021.
As of January 2020, the DDG 1000 program continues to finish construction on all three
ships while still maturing the remaining critical technologies and further defining the ship’s
new mission. The Navy planned to complete delivery of the DDG 1000 with its combat
systems in April 2020—a delay of 6 months from last year’s review. In total, the lead ship
is now 2 years late compared to the Navy’s original plans to complete this milestone.
The Navy plans to complete delivery of the DDG 1001 with its combat systems in
September 2020. Navy program officials stated that by leveraging lessons learned from
DDG 1000 combat system activation, they can complete DDG 1001 combat systems
delivery in less than 3 years. Lastly, the Navy plans to deliver DDG 1002 with its combat
systems in September 2022—a 9-month delay from last year’s estimate.
Software and Cybersecurity
As we reported last year, the Navy plans to complete software development for the class
in September 2020—a delay of 24 months since our 2018 assessment largely due to
optimistic schedules for development. As a result, the Navy has had to delay some testing
that the ship must complete before it is ready to deploy. In addition, although the lead ship
was delivered in 2016, the program is still continuing to deliver software builds that achieve
some of the promised automation. Since the software is not as capable and does not enable
as much automation as originally planned, among other things, the Navy has permanently
added 31 sailors to the crew compared to initial estimates, increasing life-cycle costs.
The program plans to complete a cybersecurity vulnerability evaluation in fiscal year 2021
connected with section 1647 of the National Defense Authorization Act for Fiscal Year
2016. The program expects that this evaluation, along with the remainder of a 2-year
regimen of certifications and several different tests in September 2020, will demonstrate
the full functionality of the ship’s systems, including cybersecurity capability. According
to program officials, no cybersecurity issues have been identified to date.
Other Program Issues

31 Source: Navy briefing for CRS and the Congressional Budget Office (CBO) on the DDG-1000 program, April 30,
2014.
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In January 2018, the Navy changed the ship class’s primary mission from land attack to
offensive surface strike and updated its requirements document to reflect this new mission
in July 2018. To begin to enable the new surface strike mission over the next 5 or more
years, the Navy is requesting $160 million for four new systems for the ships: two missile
systems, a communications system, and an intelligence system. One missile system is
planned to be installed on all three ships by September 2021 at a cost of $66 million. The
second missile system is not planned to be installed on any of the ships for at least 5 years
and needs significant development at a cost of $45 million—additional funds will be
needed to purchase and install the system. The communications system will be installed on
all three ships by fiscal 2023 and costs $22 million. Lastly, the intelligence system is not
planned to be installed on any of the ships for at least 5 years and needs significant
development at a cost of $40 million—additional funds will be needed to purchase and
install the system.
The cost to develop and install these four systems is in addition to the program’s
procurement cost as it is accounted for in other procurement and research and development
funding. According to Navy officials, the Navy may continue to add capability to support
the new mission.
Program Office Comments
We provided a draft of this assessment for program office review and comment. The
program office provided technical comments, which we incorporated where appropriate.
The office stated that it is making good progress in delivering DDG 1000 class ships to the
fleet. After our date for assessing new information from programs, the office stated that in
March 2020 the DDG 1000 had achieved sufficient combat system installation and
activation for the Navy to take delivery and transition to the next phase of developmental
and integrated at-sea testing. Further, the office said that in 2019, the DDG 1000 spent
more than 100 days at sea to maintain crew proficiency, support fleet operations, conduct
testing and provide an early opportunity for the ship to engage in operational scenarios. It
also said the DDG 1001 completed its combat availability in March 2020 with a successful
sea trial and is transitioning to combat systems activation. The office also said the final
ship of the class, DDG 1002, is under construction and 93 percent complete, and that
integration of the new systems will add offensive capability against targets afloat and
ashore across the DDG 1000 class.32
Procurement Cost Cap
Section 123 of the FY2006 defense authorization act (H.R. 1815/P.L. 109-163 of January 6, 2006)
limited the procurement cost of the fifth DDG-1000 to $2.3 billion, plus adjustments for inflation
and other factors. Given the truncation of the DDG-1000 program to three ships, this unit
procurement cost cap appears moot.
2010 Nunn-McCurdy Breach, Program Restructuring, and
Milestone Recertification
On February 1, 2010, the Navy notified Congress that the DDG-1000 program had experienced a
critical cost breach under the Nunn-McCurdy provision. The Nunn-McCurdy provision (10
U.S.C. 2433a) requires certain actions to be taken if a major defense acquisition program exceeds
(i.e., breaches) certain cost-growth thresholds and is not terminated. Among other things, a
program that experiences a cost breach large enough to qualify under the provision as a critical

32 Government Accountability Office, Defense Acquisitions Annual Assessment[:] Drive to Deliver Capabilities Faster
Increases Importance of Program Knowledge and Consistent Data for Oversight
, GAO-20-439, June 2020, p. 122.
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cost breach has its previous acquisition system milestone certification revoked. (In the case of the
DDG-1000 program, this was Milestone B.) In addition, for the program to proceed rather than be
terminated, DOD must certify certain things, including that the program is essential to national
security and that there are no alternatives to the program that will provide acceptable capability to
meet the joint military requirement at less cost.33
The Navy stated in its February 1, 2010, notification letter that the DDG-1000 program’s critical
cost breach was a mathematical consequence of the program’s truncation to three ships.34 Since
the DDG-1000 program has roughly $9.3 billion in research and development costs, truncating
the program to three ships increased to roughly $3.1 billion the average amount of research and
development costs that are included in the average acquisition cost (i.e., average research and
development cost plus procurement cost) of each DDG-1000. The resulting increase in program
acquisition unit cost (PAUC)—one of two measures used under the Nunn-McCurdy provision for
measuring cost growth35—was enough to cause a Nunn-McCurdy critical cost breach.
In a June 1, 2010, letter (with attachment) to Congress, Ashton Carter, the DOD acquisition
executive (i.e., the Under Secretary of Defense for Acquisition, Technology and Logistics), stated
that he had restructured the DDG-1000 program and that he was issuing the certifications
required under the Nunn-McCurdy provision for the restructured DDG-1000 program to
proceed.36 The letter stated that the restructuring of the DDG-1000 program included the
following:
 A change to the DDG-1000’s design affecting its primary radar.
 A change in the program’s Initial Operational Capability (IOC) from FY2015 to
FY2016.
 A revision to the program’s testing and evaluation requirements.
Regarding the change to the ship’s design affecting its primary radar, the DDG-1000 originally
was to have been equipped with a dual-band radar (DBR) consisting of the Raytheon-built X-
band SPY-3 multifunction radar (MFR) and the Lockheed-built S-band SPY-4 Volume Search
Radar (VSR). (Raytheon is the prime contractor for the overall DBR.) Both parts of the DBR
have been in development for the past several years. An attachment to the June 1, 2010, letter
stated that, as a result of the program’s restructuring, the ship is now to be equipped with “an
upgraded multifunction radar [MFR] and no volume search radar [VSR].” The change eliminates
the Lockheed-built S-band SPY-4 VSR from the ship’s design. The ship might retain a space and
weight reservation that would permit the VSR to be backfitted to the ship at a later point. The
Navy states that

33 For more on the Nunn-McCurdy provision, see CRS Report R41293, The Nunn-McCurdy Act: Background,
Analysis, and Issues for Congress
, by Moshe Schwartz and Charles V. O'Connor.
34 Source: Letter to congressional offices dated February 1, 2010, from Robert O. Work, Acting Secretary of the Navy,
to Representative Ike Skelton, provided to CRS by Navy Office of Legislative Affairs on February 24, 2010.
35 PAUC is the sum of the program’s research and development cost and procurement cost divided by the number of
units in the program. The other measure used under the Nunn-McCurdy provision to measure cost growth is average
program unit cost (APUC), which is the program’s total procurement cost divided by the number of units in the
program.
36 Letter dated June 1, 2010, from Ashton Carter, Under Secretary of Defense (Acquisition, Technology and Logistics)
to the Honorable Ike Skelton, with attachment. The letter and attachment were posted on InsideDefense.com
(subscription required) on June 2, 2010.
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As part of the Nunn-McCurdy certification process, the Volume Search Radar (VSR)
hardware was identified as an acceptable opportunity to reduce cost in the program and
thus was removed from the current baseline design....
Modifications will be made to the SPY-3 Multi-Function Radar (MFR) with the focus of
meeting ship Key Performance Parameters. The MFR modifications will involve software
changes to perform a volume search functionality. Shipboard operators will be able to
optimize the SPY-3 MFR for either horizon search or volume search. While optimized for
volume search, the horizon search capability is limited. Without the VSR, DDG 1000 is
still expected to perform local area air defense....
The removal of the VSR will result in an estimated $300 million net total cost savings for
the three-ship class. These savings will be used to offset the program cost increase as a
result of the truncation of the program to three ships. The estimated cost of the MFR
software modification to provide the volume search capability will be significantly less
than the estimated procurement costs for the VSR.37
Regarding the figure of $300 million net total cost savings in the above passage, the Navy during
2011 determined that eliminating the SPY-4 VSR from the DDG-1000 increased by $54 million
the cost to integrate the dual-band radar into the Navy’s new Gerald R. Ford (CVN-78) class
aircraft carriers.38 Subtracting this $54 million cost from the above $300 million savings figure
would bring the net total cost savings to about $246 million on a Navy-wide basis.
A July 26, 2010, press report quotes Captain James Syring, the DDG-1000 program manager, as
stating the following: “We don’t need the S-band radar to meet our requirements [for the DDG-
1000],” and “You can meet [the DDG-1000’s operational] requirements with [the] X-band [radar]
with software modifications.”39
An attachment to the June 1, 2010, letter stated that the PAUC for the DDG-1000 program had
increased 86%, triggering the Nunn-McCurdy critical cost breach, and that the truncation of the
program to three ships was responsible for 79 of the 86 percentage points of increase. (The
attachment stated that the other seven percentage points of increase are from increases in
development costs that are primarily due to increased research and development work content for
the program.)
Carter also stated in his June 1, 2010, letter that he had directed that the DDG-1000 program be
funded, for the period FY2011-FY2015, to the cost estimate for the program provided by the Cost
Assessment and Program Evaluation (CAPE) office (which is a part of the Office of the Secretary
of Defense [OSD]), and, for FY2016 and beyond, to the Navy’s cost estimate for the program.
The program was previously funded to the Navy’s cost estimate for all years. Since CAPE’s cost
estimate for the program is higher than the Navy’s cost estimate, funding the program to the
CAPE estimate for the period FY2011-FY2015 will increase the cost of the program as it appears
in the budget for those years. The letter states that DOD “intends to address the [resulting]
FY2011 [funding] shortfall [for the DDG-1000 program] through reprogramming actions.”
An attachment to the letter stated that the CAPE in May 2010 estimated the PAUC of the DDG-
1000 program (i.e., the sum of the program’s research and development costs and procurement

37 Source: Undated Navy information paper on DDG-51 program restructuring provided to CRS and CBO by Navy
Office of Legislative Affairs on July 19, 2010.
38 Source: Undated Navy information paper on CVN-78 cost issues, provided by Navy Office of Legislative Affairs to
CRS on March 19, 2012.
39 Cid Standifer, “Volume Radar Contracted For DDG-1000 Could Be Shifted To CVN-79,” Inside the Navy, July 26,
2010. See also Joseph Trevithick and Tyler Rogoway, “Navy's Troubled Stealth Destroyers May Have Radars
Replaced Before Ever Sailing On A Mission,” The Drive, October 15, 2020.
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costs, divided by the three ships in the program) as $7.4 billion per ship in then-year dollars
($22.1 billion in then-year dollars for all three ships), and the program’s average procurement unit
cost (APUC), which is the program’s total procurement cost divided by the three ships in the
program, as $4.3 billion per ship in then-year dollars ($12.8 billion in then-year dollars for all
three ships). The attachment stated that these estimates are at a confidence level of about 50%,
meaning that the CAPE believes there is a roughly 50% chance that the program can be
completed at or under these cost estimates, and a roughly 50% chance that the program will
exceed these cost estimates.
An attachment to the letter directed the Navy to “return for a Defense Acquisition Board (DAB)
review in the fall 2010 timeframe when the program is ready to seek approval of the new
Milestone B and authorization for production of the DDG-1002 [i.e., the third ship in the
program].”
On October 8, 2010, DOD reinstated the DDG-1000 program’s Milestone B certification and
authorized the Navy to continue production of the first and second DDG-1000s and commence
production of the third DDG-1000.40


Author Information

Ronald O'Rourke

Specialist in Naval Affairs



Disclaimer
This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan
shared staff to congressional committees and Members of Congress. It operates solely at the behest of and
under the direction of Congress. Information in a CRS Report should not be relied upon for purposes other
than public understanding of information that has been provided by CRS to Members of Congress in
connection with CRS’s institutional role. CRS Reports, as a work of the United States Government, are not
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copy or otherwise use copyrighted material.


40 Christopher J. Castelli, “Pentagon Approves Key Milestone For Multibillion-Dollar Destroyer,” Inside the Navy,
November 22, 2010.
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