Navy DDG-51 and DDG-1000 Destroyer
Programs: Background and Issues for
Congress
Updated August 8, 2023
Congressional Research Service
https://crsreports.congress.gov
RL32109

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

Summary
The Arleigh Burke (DDG-51) class destroyer program is one of the longest-running shipbuilding
programs in Navy history. The Navy began procuring DDG-51s, also known as Aegis destroyers,
in FY1985, and a total of 92 have been procured through FY2023, including three in FY2023.
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 in FY2006-FY2009. Instead, the Navy in FY2007-
FY2009 procured three Zumwalt [DDG-1000] class destroyers. The Navy plans no further
procurement of DDG-1000s.)
The Navy’s proposed FY2024 budget requests the procurement of two more DDG-51s in
FY2024. The Navy’s FY2024 five-year (FY2024-FY2028) shipbuilding plan includes 10 DDG-
51s, to be procured at a rate of two ships per year.
As part of its FY2023 budget submission, the Navy requested authority for using a multiyear
procurement (MYP) contract for DDG-51s scheduled for procurement in FY2023-FY2027.
Congress, as part of its action on the Navy’s proposed FY2023 budget, approved this request.
Four previous MYP contracts for the DDG-51 program covered DDG-51s procured in FY1998-
FY2001, FY2002-FY2005, FY2013-FY2017, and FY2018-FY2022.
The first DDG-51 entered service in 1991, and a total of 72 have been delivered as of March
2023. The DDG-51 design has been updated multiple times over the years; the version currently
being procured, called the Flight III DDG-51 design, incorporates a new and more capable radar
called the SPY-6 radar.
DDG-51s currently cost about $2.2 billion each to procure. The budget estimates the combined
procurement cost of the two DDG-51s requested for procurement in FY2024 at $4,432.8 million
(i.e., about $4.4 billion). The two ships have received $233.6 million in prior-year Economic
Order Quantity (EOQ) funding, which is a kind of advance procurement (AP) funding that can
occur under an MYP contract. The Navy’s proposed FY2024 budget requests the remaining
$4,199.2 million needed to complete the two ships’ estimated combined procurement cost. The
Navy’s proposed FY2024 budget also requests $284.0 million in EOQ funding for DDG-51s to be
procured under the FY2023-FY2027 MYP contract, and $225.9 million in cost-to-complete
funding to cover cost growth on DDG-51s procured in prior fiscal years.

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Appendixes
Appendix. Additional Background Information on DDG-1000 Program ..................................... 16

Contacts
Author Information ........................................................................................................................ 28

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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 92 have
been procured through FY2023, including three in FY2023. The Navy’s FY2024 budget requests
the procurement of two DDG-51s in FY2024.
Potential issues for Congress for the DDG-51 program in FY2024 include the Navy’s future
force-level goal for large surface combatants (or LSCs, meaning cruisers and destroyers), 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) Next-Generation
Destroyer 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 Level as of End of FY2022
As of the end of FY2022, the Navy’s LSC force included 90 ships, including 17 Ticonderoga
(CG-47) class cruisers,2 72 DDG-51s, and one Zumwalt (DDG-1000) class destroyer.

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 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). Of the remaining 22, five were
retired in FY2022, leaving 17 in service at the end of FY22.
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Current and Potential Future LSC Force-Level Goal
Current LSC Force-Level Goal Within 355-Ship Plan of December 2016
The Navy’s current force-level goal, released in December 2016, calls for achieving and
maintaining a fleet of 355 ships, including 104 LSCs.3
Successor Force-Level Goal to Replace 355-ship Goal of 2016
The Navy and the Department of Defense (DOD) have been working since 2019 to develop a
successor for the 355-ship force-level goal. The Navy’s FY2023 30-year (FY2023-FY2052)
shipbuilding plan, released on April 20, 2022, includes a table summarizing the results of studies
that have been conducted on the successor force-level goal. These studies outline potential future
fleets with 63 to 96 LCSs.4
DDG-51 Program
Overview
The DDG-51 program was initiated in the late 1970s.5 It is one of the longest-running
shipbuilding programs in Navy history, and the DDG-51 class is one of the Navy’s numerically
largest classes of ships since World War II. The first DDG-51 was procured FY1985, and a total
of 92 have been procured through FY2023, including three in FY2023. 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 in FY2006-FY2009. Instead, the Navy in FY2007-FY2009
procured three Zumwalt [DDG-1000] class destroyers, which are discussed later in this report.
The first DDG-51 entered service in 1991, and a total of 72 have been delivered as of March
2023. The remaining 20 DDG-51s are in various stages of construction. Earlier DDG-51s, known
as the Flight I/II DDG-51s, generally have an estimated service life (ESL) of 35 years, meaning
that retirement of these ships could begin in the late 2020s. An exception to the 35-year ESL for
the Flight I/II DDG-51s is the very first ship in the class—DDG-51 itself—which has been
certified for a 40-year life. Additional Flight I/II DDG-51s might eventually receive similar
certifications, depending on their condition and Navy mission needs. Later DDG-51s, known as
the Flight IIA and Flight III DDG-51s, have an estimated service life of 40 years.
DDG-51s (Figure 1 and Figure 2) 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 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

3 For additional discussion, see CRS Report RL32665, Navy Force Structure and Shipbuilding Plans: Background and
Issues for Congress, by Ronald O'Rourke.
4 For additional discussion, see CRS Report RL32665, Navy Force Structure and Shipbuilding Plans: Background and
Issues for Congress, by Ronald O'Rourke.
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.
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Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress

several times over the years. Many DDG-51s (and also some CG-47s) have a capability for
conducting ballistic missile defense (BMD) operations.6
Figure 1. DDG-51 Class Destroyer

Source: Cropped version of photograph at Huntington Ingalls Industries, “Delbert Black (DDG 119) Completes
Builder’s Trials,” February 26, 2020, accessed November 17, 2021, at https://newsroom.huntingtoningalls.com/
file/delbert-black-ddg119-builders-trials.
Design Changes
The DDG-51 design has been modified and updated periodically over the years. The first 28
DDG-51s (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 (DDGs 79
through 124 and DDG-127) were procured in FY1994-FY2016. In FY2017, the Navy shifted
DDG-51 procurement to the current Flight III DDG-51 design, which incorporates a new and
more capable radar called the SPY-6 radar (previously known as the Air and Missile Defense
Radar, or AMDR), as well as associated changes to the ship’s electrical power and cooling
systems. DDGs 125 and higher, except for DDG-127 as noted above, are to be Flight III DDG-
51s.
Multiyear Procurement (MYP)
As part of its FY2023 budget submission, the Navy requested authority for using a multiyear
procurement (MYP) contract for DDG-51s scheduled for procurement in FY2023-FY2027.7
Congress, as part of its action on the Navy’s proposed FY2023 budget, approved this request.8

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.
7 For more on MYP contracting, see CRS Report R41909, Multiyear Procurement (MYP) and Block Buy Contracting
in Defense Acquisition: Background and Issues for Congress, by Ronald O'Rourke.
8 See Section 125 of the FY2023 National Defense Authorization Act (NDAA) (H.R. 7776/P.L. 117-263 of December
(continued...)
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Four previous MYP contracts for the DDG-51 program covered DDG-51s procured in FY1998-
FY2001, FY2002-FY2005, FY2013-FY2017, and FY2018-FY2022.
Figure 2. DDG-51 Class Destroyer

Source: Cropped version of undated photograph of USS Jason Dunham (DDG-109) at “Bath Iron Works,”
accessed November 17, 2021, at https://www.gd.com/our-businesses/marine-systems/bath-iron-works.
Shipbuilders, Combat System Lead, and Radar Maker
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.9

23, 2022) and Section 8010 of the FY2023 DOD Appropriations Act, (Division C of H.R. 2617/P.L. 117-328 of
December 29, 2022).
9 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
(continued...)
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FY2024 Procurement Funding Request
The Navy’s proposed FY2024 budget requests the procurement of two more DDG-51s in
FY2024. The budget estimates the combined procurement cost of the two ships at $4,432.8
million (i.e., about $4.4 billion). The two ships have received $233.6 million in prior-year
Economic Order Quantity (EOQ) funding, which is a kind of advance procurement (AP) funding
that can occur under an MYP contract. The Navy’s proposed FY2024 budget requests the
remaining $4,199.2 million needed to complete the two ships’ estimated combined procurement
cost. The Navy’s proposed FY2024 budget also requests $284.0 million in EOQ funding for
DDG-51s to be procured under the FY2023-FY2027 MYP contract, and $225.9 million in cost-
to-complete funding to cover cost growth on DDG-51s procured in prior fiscal years.
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)10 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 $800,000.11
In December 2017, it was reported that, due to shifts in the international security environment and
resulting shifts in Navy mission needs, the mission orientation of the DDG-1000s would 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.12
As noted in the Appendix, the DDG-1000 program’s originally scheduled date for achieving
Initial Operating Capability (IOC) was FY2015. The date for achieving IOC, however, has been
repeatedly delayed. In February 2022, it was reported that the date had been delayed from
September 2021 to December 2021, but that the December 2021 date was not achieved, and that
the Navy was reevaluating the timeline for achieving IOC.13
To further optimize the three ships for conducting surface strike missions, the Navy reportedly
plans to remove their AGSs and associated below-deck equipment and replace them with large-
diameter vertical launch tubes capable of storing and firing the Navy’s new hypersonic

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).
10 NSFS is the use of naval guns to provide fire support for friendly forces operating ashore.
11 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.
12 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.
13 Audrey Decker, “Zumwalt’s Initial Operational Capability Delayed Again,” Inside Defense, February 25, 2022.
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Conventional Prompt Strike (CPS) missile, with a goal of having the first CPS-equipped DDG-
1000 class ship ready for testing by 2025. Each DDG-1000 class ship reportedly is to be equipped
with four of the large-diameter tubes, with each tube capable of holding three CPS missiles, for a
total of 12 CPS missiles per ship.14
The Navy reportedly also wants to replace some of the combat system equipment on the three
ships with equipment more similar to, and interoperable with, combat system equipment on other
U.S. Navy surface combatants. The Navy refers to this as the Zumwalt Enterprise Upgrade
Solution (ZEUS).15
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 of these shipyards 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
SPY-6 radar 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 SPY-6.

14 See, for example, Mallory Shelbourne, “Navy Planning for December 2025 Hypersonic Missile Test off USS
Zumwalt,” USNI News, February 1, 2023; Kyle Mizokami, “The Navy’s Stealth Destroyers Are Getting a Serious
Upgrade: 12 Hypersonic Missiles Each,” Popular Mechanics, December 1, 2022; Sam LaGrone, “Navy Details
Hypersonic Missile Plan for Zumwalt Destroyers, Virginia Submarines,” USNI News, November 3, 2022; Sam
LaGrone, “HII Set to Install First Hypersonic Missiles on USS Zumwalt, USS Michael Monsoor During Repair
Period,” USNI News, August 12, 2022; Sam LaGrone, “Latest Zumwalt Hypersonic Missile Installation Plan Calls For
Removing Gun Mounts,” USNI News, March 16, 2022; Joseph Trevithick, “The Navy’s Stealth Destroyers Will Have
Their Deck Guns Replaced With Hypersonic Missiles,” The Drive, November 2, 2021; Rich Abott, “Navy Plans to
Field 12 Hypersonic Missiles on Each Zumwalt Destroyer, Replacing Gun,” Defense Daily, June 8, 2021; Jason
Sherman, “Navy Plans to Pack Each DDG-1000 with 12 Long-Range Hypersonic Strike Missiles,” Inside Defense,
June 8, 2021; Jason Sherman, “Navy to Rip Out DDG-1000 Advanced Gun System Mounts to Make Room for
Hypersonic Weapons,” Inside Defense, May 26, 2021; Sam LaGrone, “CNO: Hypersonic Weapons at Sea to Premiere
on Zumwalt Destroyers in 2025,” USNI News, April 28, 2021; David B. Larter, “What Should Become of the Zumwalt
Class? The US Navy Has Some Big Ideas,” Defense News, March 25, 2021; Joseph Trevithick, “Navy Wants Triple-
Packed Hypersonic Missile Modules On Its Stealthy Zumwalt Destroyers,” The Drive, March 19, 2021; Paul McLeary,
“Exclusive[:] Eying China, CNO Plans Hypersonics & Lasers On Zumwalt Destroyers,” Breaking Defense, February
26, 2021. For more on the CPS program, see CRS Report R41464, Conventional Prompt Global Strike and Long-
Range Ballistic Missiles: Background and Issues, by Amy F. Woolf.
15 See, for example, Kyle Mizokami, “The Navy’s Stealth Destroyers Are Getting a Serious Upgrade: 12 Hypersonic
Missiles Each,” Popular Mechanics, December 1, 2022; Mallory Shelbourne, “Navy Exploring ‘Surface Strike’
Upgrades for Zumwalt Destroyers,” USNI News, November 28, 2022; Justin Katz, “Navy Eyeing ‘ZEUS,’ an Upgrade
Program for the Zumwalt Destroyers,” Breaking Defense, November 22, 2022.

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The surface combatant construction industrial base also includes hundreds of additional firms that
supply materials and components. 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 for the DDG-51 concerns the future LSC force-level goal. As noted
above, studies conducted on the Navy’s next force-level goal outline potential future fleets with
63 to 96 LCSs. Reducing the LSC force-level goal from the current required figure of 104 ships
to a smaller number—particularly a number closer to 63 ships—could affect issues such as when
to retire older LSCs and how many new LSCs to procure each year. An August 1, 2022, press
report stated
In little more than five months, the shape of America’s future Navy fleet changed. Between
February and July, U.S. Navy leadership went from advocating for a modest fleet of 60
cruisers and destroyers to supporting a more robust vision of 96 large surface combatants
by 2045.
Nobody really knows what, exactly, pushed the Navy to favoring large combatants—a
rating traditionally comprised of high-value cruisers and destroyers. Neither the U.S.
Department of Defense, the Secretary of the Navy, nor America’s Chief of Naval
Operations, Admiral Mike Gilday, has offered taxpayers any real detail on what spurred
the Navy, after years of fretting over the relevance of large surface combatants, to redirect
at least $70 billion in future funding towards building bigger ships.
The shift was abrupt. In February, at the annual WEST 2022 conference in San Diego,
Gilday sketched out a future fleet of 60 large and 50 small combatants, breaking from the
traditional 355-ship fleet goal of maintaining a 2:1 ratio of large combatants (cruisers and
destroyers) to small vessels (frigates and Littoral Combat Ships). Last month, Gilday
changed his tune, releasing a “2022 Navigation Plan,” aiming for a fleet of 96 large
combatants by 2045.
Both targets are out of step with the 30-year shipbuilding plan detailed in April’s “Report
to Congress on the Annual Long-Range Plan for Construction of Naval Vessels for Fiscal
Year 2023,” which suggested to Congress that the Navy was intent upon fielding a fleet of
between 70 to 80 large surface combatants by 2045....
Given the public reporting to date, it is tough to tell what, exactly, is driving the Navy’s
sudden interest in large surface combatants. Industry press has been less than dogged in its
efforts to understand the dramatic—if not unprecedented—oscillation in the U.S. Navy’s
demand for large surface combatants.
That failure is unfortunate, as America’s public and policymaker communities need clarity
more than ever....
While the Navy’s growing appetite for large surface combatants—whatever they might
turn out to be—is welcome news for the large surface combatant industrial base, the Navy’s
inability to fix on a consistent plan is a public relations and strategic disaster....
With no viable strategic or tactical justification forthcoming from Navy leadership, the
Navy’s free-form approach to the future of the surface fleet does little more than bemuse
rivals and irk everybody else. The Navy has little room to make sudden whipsaw changes.
After repeated operational fiascoes, the U.S. Navy has little credibility right now, and an
unexplained strategic change leaves pro-Navy advocates confused, and an already
impatient Congress frustrated....
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The embrace of big ships in Gilday’s new force structure turns distributed lethality on its
head. Rather than working to grow the small-surface combatant fleet and using those
vessels to smear sensors and shooters all over the sea, the surface Navy is, with DDG(X),
re-inventing the battleship and, apparently, returning to the traditional World War II-era
battle group, leaving distributed lethality for crew-less things.
That’s fine. But, as originally articulated, the Distributed Maritime Operations concept was
set to push the fleet towards a 2:1 ratio of smaller crewed ships to bigger crewed surface
combatants. If the mechanics behind Distributed Maritime Operations are shifting to feed
the Navy’s craving for larger vessels, that shift—particularly if it is sacrificing smaller
crewed vessels for robots—is worth a bit of public discussion.16
Section 121 of the FY2021 National Defense Authorization Act (H.R. 6395/P.L. 116-283 of
January 1, 2021) 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
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.
Shipbuilding Industrial-Base Capacity and DDG-51 Procurement
Rate
Another issue for Congress concerns the shipbuilding industrial base’s capacity for building
DDG-51s, and the impact this could have on the DDG-51 procurement rate, specifically on the
question of whether to procure two or three DDG-51s per year. A March 21, 2023, press report
stated:

16 Craig Hooper, “Battleships Are Back! Navy Abruptly Boosts DDG/CG Building Targets For 2045,” Forbes, August
1, 2022.
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The Navy is keeping a two-ship-per-year cadence for its destroyer line because that’s a
realistic goal for industry to work toward, according to the Pentagon’s top budget officer.
Despite Congress’ push for the Navy to start buying three Arleigh Burke-class Flight III
destroyers per year, the Fiscal Year 2024 budget request unveiled last week showed the
service buying two destroyers. That’s because U.S. shipyards are not yet able to build two
destroyers per year, let alone three, Mike McCord said last week.
“I’m not hating on DDGs – my only point was that last year Congress added a third and
the reason we didn’t budget for three is, again, we don’t see the yards being able to produce
three a year. We don’t see them being able to produce two a year. And that’s just data. It’s
not what we wish to be true. But everybody’s struggling with skilled labor. Everybody’s
struggling with supply chain. So it’s not getting better very fast from the data that I’ve seen
– whether with submarines or DDGs. So two a year seems to be a reasonable place,”
McCord told USNI News at the McAleese Conference.
During the [FY2024] budget rollout last week, McCord said industry is currently building
1.5 destroyers per year, a number Chief of Naval Operations Adm. Mike Gilday has also
cited when arguing that the shipyards have limited capacity.
McCord also argued that asking for more destroyers than industry can build takes away
leverage from the Navy to negotiate with shipbuilders on price.
“If you keep sort of placing orders for things faster than they can be delivered, it’s good
for the books, the balance sheets of the companies. But are you really, as the buyer, are you
in the best place you’d like to be with any leverage or are you actually short of leverage
when, you produce on time or you don’t produce on time. It doesn’t matter to me – I’m
going to keep writing you checks,” McCord told USNI News.
The comptroller said both he and Susanna Blume, the director of the Cost Assessment and
Program Evaluation (CAPE) Office of the Secretary of Defense, don’t think putting more
funding toward an extra destroyer is a wise use of resources that will help shipbuilders
deliver it to the Navy quicker.
“It’s just sort of piling up in the orders book and we’re still going to have the same problems
of the yards producing faster until we get through the supply chain and the workforce
issues,” McCord said. “It is not to say that we would not be interest[ed] in a more robust
production world where in having three DDGs or moving to three submarines, but it
doesn’t seem to be … realistic.”
General Dynamics Bath Iron Works, one of the yards that build the destroyers, has spent
the last several years digging through a backlog of work at its Maine yard that the COVID-
19 pandemic exacerbated. HII’s Ingalls Shipbuilding, the other yard that builds the Arleigh
Burke destroyers, has performed better. Ingalls is also winding down the Coast Guard’s
Legend-class National Security Cutter production line, which could open up more capacity
at its yard in Pascagoula, Miss.
A spokeswoman for Ingalls Shipbuilding told USNI New in a statement that the yard is
ready to support building three destroyers per year should the Navy go this route.
“Our shipbuilders will position to support whatever destroyer cadence the Navy needs and
we have started by building, testing and taking the first Flight III ship to sea, which will be
delivered later this year. We are a committed partner to not only our customers but to our
network of nearly 1,200 suppliers as well. Together, we can build three DDGs a year if that
is what the Navy and our country need,” Kimberly Aguillard said in a statement.
A spokesperson for Bath Iron Works told USNI News that it’s “working to aggressively
recover schedule” at the shipyard.
“We support the call for a consistent demand signal that gives shipyards and suppliers the
predictability to make major investments in workforce and facilities, both to expand
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destroyer production and to ensure that capability remains intact well into the future,”
David Hench said in a statement. “Those capital investments are currently underway in
Bath, and we are confident there will be significant schedule improvement so we can meet
the Navy’s expectations by the time construction begins on the anticipated multi-year
contract.”
Lawmakers have urged the Navy to work toward buying three destroyers per year and
added a third destroyer on top of the Navy’s request for two in FY 2023. Congress also
included a provision in the FY 2023 policy bill that would allow the Navy to ink a multi-
year procurement deal for as many as 15 Flight III destroyers. If the multi-year procurement
contracts are for fewer than 15 destroyers, the Navy must include at least one “pre-priced
option” so it has the opportunity to buy 15 ships, according to the bill language.17
Transition of Procurement from DDG-51s to DDG(X)s
Another issue for Congress concerns 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. DON’s
prepared statement for the April 26, 2022, hearing on DON investment programs before the
Seapower subcommittee of the Senate Armed Services Committee states
The Navy is committed to a smooth and successful transition from DDG 51 to DDG(X)
starting around FY 2030.18 The transition will preserve the critical shipbuilding and
supplier industrial base by executing a collaborative design process with current DDG 51
shipyards and transitioning to a proven limited competition model between these shipyards
at the right point in ship construction.19
The Navy’s FY2024 budget submission states that “early DDG(X) production transition will
overlap DDG 51 FLT III production ensuring stability in the Large Surface Combatant industrial
base.”20
For more on the DDG(X) program, see CRS In Focus IF11679, Navy DDG(X) Next-Generation
Destroyer Program: 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.
A June 2023 Government Accountability Office (GAO) report assessing selected DOD
acquisition programs stated the following in its assessment of the Flight III DDG-51:

17 Mallory Shelbourne, “OSD Comptroller Says U.S. Shipyards Can’t Build 3 Destroyers a Year,” USNI News, March
21 (updated March 22), 2023.
18 Under the Navy’s proposed FY2024 budget, procurement of the first DDG(X) has been deferred from FY2030 to
FY2032.
19 Statement of Frederick J. Stefany, Principal Civilian Deputy, Assistant Secretary of the Navy (Research,
Development and Acquisition), Performing the Duties of the Assistant Secretary of the Navy (Research, Development
and Acquisition), and Vice Admiral Scott Conn, Deputy Chief of Naval Operations, Warfighting Requirements and
Capabilities (OPNAV N9), and Lieutenant General Karsten S. Heckl, Deputy Commandant, Combat Development and
Integration, Commanding General, Marine Corps Combat Development Command, before the Subcommittee on
Seapower of the Senate Armed Services Committee on Department of the Navy Fiscal Year 2023 Budget Request for
Seapower, April 26, 2022, PDF page 10 of 37.
20 Department of Defense Fiscal Year (FY) 2024 Budget Estimates, Navy, Justification Book, Volume 2 of 5, Research,
Development, Test & Evaluation, Navy, March 2023, p. 453.
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Current Status
The program reported that the first eight DDG 51 Flight III ships are under construction,
with an additional six under contract, and the Navy plans to deliver the lead ship—DDG
125—in June 2023. Program officials noted that there is a risk to the delivery schedule due
to first-time integration of the new electrical power system and combat system. They said
that they plan to use recently completed sea trials and further testing to mitigate these risks.
The program pushed back the planned start of sea trials from September 2022 to December
2022 due to these first-time integration challenges and continues to assess cost and
schedule effects, according to program officials. We previously reported on risks to
program cost and schedule due to power system updates after tests on Flight IIA ships
showed the initial system did not meet requirements. The program mitigated this risk with
a replacement power system on Flight IIA ships, according to program officials.
The program experienced additional cost growth for the first two Flight III ships over the
past year and reported receiving $168 million in fiscal year 2023 to cover the government’s
portion of cost overruns for certain contracts. Program officials told us that the cost growth
is primarily due to first time build challenges and is capped by the price ceiling on the
contract.
The Navy purchased a total of 14 Flight III ships thus far and received authority to enter
into one or more multiyear contracts to procure up to 15 ships starting in fiscal year 2023,
according to program officials. Competition for these procurement contracts is ongoing.
This plan aligns with the Navy’s current long-range planning for force structure
requirements.
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.
According to the program, the Arleigh Burke class destroyer is one of the Navy’s longest-
running production lines, which delivered 72 ships. Production continues with a number
of ships under contract, in various stages of production, and in preconstruction activities,
according to the program. It added that, in addition to ongoing progress to deliver the final
few Flight IIA destroyers, the program continues toward Flight III delivery, test and
evaluation, and deployment.21
Regarding the AMDR specifically, the report stated the following:
Technology Maturity, Design Stability, Production Readiness
As we reported last year, AMDR fully matured its critical technologies in December 2021
and its overall design remains stable. The Navy plans to start operational testing of AMDR
and Aegis at sea on DDG 125 in November 2023.
Since last year, AMDR’s low-rate initial production contract’s estimated price increased.
According to program officials, this increase was due to earlier optimistic cost estimating
by the contractor, supply chain challenges, and issues with the Digital Receiver Exciter
(DREX) and Transmit/Receive Integrated Microwave Modules (TRIMM). We previously
reported on manufacturing issues with the DREX and TRIMM that required the program
to complete some redesign and rework. According to program officials, the contractors
addressed these issues and took into account the actual costs from the low-rate initial
production contract when preparing to award the follow-on contract, which was awarded
in March 2022.

21 Government Accountability Office, Weapon Systems Annual Assessment[:] Programs Are Not Consistently
Implementing Practices That Can Help Accelerate Acquisitions, GAO-23-106059, June 2023, p. 163.
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The program continued delivery of radar arrays in 2022. It briefly held up delivery of two
arrays after discovering cracking in the material used to fabricate them. Program officials
stated that they determined the arrays were within standards but added an inspection step
for all future radars to ensure this component continues to meet standards. Program
officials told that us they believe this step provides reasonable assurance for future
performance.
Program officials also plan to take remedial actions to investigate and address any further
issues found with inverter modules after a single module grounded out, causing it to burn
during initial testing. According to program officials, these modules are a critical part of
the power supply system. Program officials told us that they do not expect this issue to
affect deliveries or program costs.
Software and Cybersecurity
AMDR is using a hybrid Agile and incremental software development approach.
According to the program office, software is released at various intervals—every 4 weeks
for interim releases and builds every year.
The program completed several cybersecurity exercises and, according to officials, plans
to include cybersecurity testing during operational testing in 2024. Program officials
continue to track a risk from cyber threats related to countermeasures seeking to defeat the
radar. They plan to address this risk as part of upcoming cybersecurity testing through
2025.
Other Program Issues
AMDR officials plan to complete operational testing in August 2024, the same month as
the planned full-rate production decision. This schedule leaves little time for the program
to address any deficiencies discovered during testing. We previously reported that any
deficiencies discovered during testing could result in costly and time-intensive revisions
for the program. Program officials acknowledge this issue and plan to continue testing
radar performance and power requirements in advance of operational testing to mitigate
the risk of late discovery of issues in these areas.
AMDR officials stated that the radar performed well as an informal participant in the
August 2022 Pacific Dragon exercise, where the radar tracked live missile and aircraft
activity. Despite performing well, the program identified some issues during this exercise
and plans to run separate high-fidelity performance test scenarios prior to the start of
operational testing.
Program officials stated that they made adjustments and conducted additional power
system testing with all four arrays in fall 2022. This testing was in response to a risk that
prior testing could not adequately model expected operational conditions. We previously
reported that the program planned full-array power testing by the end of fiscal year 2022.
According to program officials, these interim tests should improve performance during
operational testing and reduce risk to meeting power requirements.
The program updated its baseline in January 2023. The update designated two EASR
variants as subprograms of the AMDR program. As we previously reported, the Navy plans
to install the two EASR variant systems on several classes of Navy ships. The program is
tracking related risks, and program officials told us that they plan tests in February and
March 2023 to help mitigate these risks.
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 office stated that it is on track to support DDG 125’s schedule and that it
successfully completed full-array power testing and supported the ship’s December 2022
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sea trial. It also stated that integrated live-radar and combat system testing continues to
support various classes of Navy ships.22
Legislative Activity for FY2024
Summary of Congressional Action on FY2024 Funding Request
The Navy’s proposed FY2024 budget requests the procurement of two DDG-51s in FY2024. The
budget estimates the combined procurement cost of the two ships at $4,432.8 million (i.e., about
$4.4 billion). The two ships have received $233.6 million in prior-year Economic Order Quantity
(EOQ) funding, which is a kind of advance procurement (AP) funding that can occur under an
MYP contract. The Navy’s proposed FY2024 budget requests the remaining $4,199.2 million
needed to complete the two ships’ estimated combined procurement cost. The Navy’s proposed
FY2024 budget also requests $284.0 million in EOQ funding for DDG-51s to be procured under
the FY2023-FY2027 MYP contract, and $225.9 million in cost-to-complete funding to cover cost
growth on DDG-51s procured in prior fiscal years.
The Navy’s proposed FY2024 budget also requests $410.4 million in continued procurement
funding for the DDG-1000 program. The Navy’s FY2024 budget submission states that $234
million of the $410.4 million is for modifying the third ship in the program (DDG-1002) during
its construction to include large-diameter vertical launch tubes capable of storing and firing the
Navy’s new hypersonic Conventional Prompt Strike (CPS) missile.23 (Costs to modify the first
two DDG-1000 class ships—DDG-1000 and DDG-1001—for the CPS are budgeted in the Other
Procurement, Navy [OPN] appropriation account.)
Table 1 summarizes congressional action on the Navy’s FY2024 procurement funding requests
for the DDG-51 and DDG-1000 programs.
Table 1. Congressional Action on FY2024 Funding Request
Millions of dollars, rounded to nearest tenth
Authorization
Appropriation

Request
HASC
SASC
Final
HAC
SAC
Final
DDG-51 procurement
4,199.2
4,199.2
4,199.2

4,199.2
4,499.2

Quantity
(2)
(2)
(2)

(2)
(2)

DDG-51 advance procurement (EOQ AP)
284.0
439.0
284.0

284.0
1,641.3

DDG-51 cost to complete
225.9
225.9
225.9

225.9
325.9

DDG-1000 procurement
410.4
410.4
410.4

318.7
410.4

Sources: Table prepared by CRS based on Navy’s FY2024 budget submission, committee and conference
reports, and explanatory statements on FY2024 National Defense Authorization Act and FY2024 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.

22 Government Accountability Office, Weapon Systems Annual Assessment[:] Programs Are Not Consistently
Implementing Practices That Can Help Accelerate Acquisitions, GAO-23-106059, June 2023, p. 140.
23 Department of Defense, Fiscal Year (FY) 2024 Budget Estimates, Navy Justification Book Volume 1 of 1,
Shipbuilding and Conversion, Navy, March 2023, pp. 178-179.
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FY2024 National Defense Authorization Act (H.R. 2670/S. 2226)
House
The House Armed Services Committee, in its report (H.Rept. 118-125 of June 30, 2023) on H.R.
2670, recommended the funding levels shown in the HASC column of Table 1. The
recommended increase of $155.0 million in DDG-51 advance procurement (AP) funding is for
“Explosion welding” ($5.0 million) and “Program increase” ($150.0 million). (Page 445)
Section 862 of H.R. 2670 would permit the DOD Industrial Base Fund to be used to provide
support for the workforce for LSCs.
H.Rept. 118-125 states:
DDG 51 degaussing
The committee is concerned about the threat posed by magnetic mines, particularly as it
pertains to adversaries’ anti-access/area denial strategies. For the past several years,
Congress required the Navy to review the threat and funded lightweight advanced
degaussing systems to counter magnetic mines. However, the committee remains
concerned about the Navy’s lack of a comprehensive plan to ensure that Arleigh Burke-
class destroyers are adequately protected.
Therefore, the committee directs the Secretary of the Navy to provide a briefing to the
House Committee on Armed Services not later that December 15, 2023, on the Navy’s plan
to modernize the DDG 51 to effectively mitigate the threat from magnetic mines. The
report should include at a minimum the following information: (1) an assessment of the
threat from magnetic influence mines; and (2) a cost estimate to install lightweight
advanced degaussing systems on all DDG 51 class destroyers. (Pages 19-20)
Senate
The Senate Armed Services Committee, in its report (S.Rept. 118-58 of July 12, 2023) on S.
2226, recommended the funding levels shown in the SASC column of Table 1.
S.Rept. 118-58 states:
Large surface combatants
The U.S. Navy needs to make progress toward the goal of a 355-ship fleet. DDG–51
destroyers will be an integral part of any plan to achieve that goal because they provide
significant multi-mission capability, including strategic land strike; anti-aircraft, anti-
surface ship, and anti-submarine warfare; and ballistic missile defense.
In addition to falling short of its stated goal of 355 ships, the Department of the Navy
remains short of sufficient large surface combatants. The U.S. Navy will have an inventory
of 85 large surface combatants in fiscal year 2023. This number is projected to decline to
as few as 77 large surface combatants in the fiscal year 2031 and does not return to the
current level of 85 ships before the fiscal year 2038. This is well short of the 120 ships
identified in the analysis that led to the Department goal of 355 ships later codified in law.
Section 125 of the James M. Inhofe National Defense Authorization Act for Fiscal Year
2023 (Public Law 117–263) provided new multi-year contract authority for up to 15 DDG–
51s over five years and authorized the U.S. Navy to procure 3 DDG–51s in fiscal year
2023.
The U.S. Navy continues to work towards developing the next generation destroyer
(DDG(X)), which will have the size and power capabilities to house next-generation
weapons while maintaining this multi-mission capability. The committee continues to
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encourage the U.S. Navy, per section 130 of the James M. Inhofe National Defense
Authorization Act for Fiscal Year 2023 (Public Law 117–263), to pursue a collaborative
design, development, and acquisition strategy for DDG(X). Early collaboration between
the U.S. Navy, shipbuilders, and major component producers allows for greater design
maturity and cost efficiency. Part of this strategy, as Navy officials have stated in
congressional testimony, should be to continue to build DDG–51 Flight III destroyers
concurrently with the DDG(X) at the beginning of DDG(X) production to keep Flight III
capability flowing to the fleet, while sustaining a fragile shipbuilding industrial base. The
committee believes a consistent demand signal to the shipbuilding industrial base is critical
to driving the hiring and training of the shipbuilding workforce at all levels. (Page 23)
FY2024 DOD Appropriations Act (H.R. 4365/S. 2587)
House
The House Appropriations Committee, in its report (H.Rept. 118-121 of June 27, 2023) on H.R.
4365, recommended the funding levels shown in the HAC column of Table 1. The recommended
reduction of $91.745 million for DDG-1000 procurement is for “TSCE [Total Ship Computing
Environment] modernization previously funded” ($56.730 million) and “Mission systems
activation unjustified growth” ($35.015 million). (Page 145)
Senate
The Senate Appropriations Committee, in its report (S.Rept. 118-81 of July 27, 2023) on S. 2587,
recommended the funding levels shown in the SAC column of Table 1.
The recommended increase of $300 million for DDG-51 procurement funding is for “Program
increase: Large surface combatant shipyard infrastructure.” (Page 135)
The recommended increase of $1,357.3 million for DDG-51 advance procurement (AP) funding
is for “Program increase: Advance procurement for additional FY25 DDG 51” ($1,280.0 million)
and “Realignment of fiscal year 2023 funds for advance procurement of additional FY25 DDG
51” ($77.3 million). (Page 135). (Section 8045 of S. 2587 would rescind $77.3 million in FY2023
DDG-51 advance procurement [AP] funding.)
The recommended increase of $100.0 million in DDG-51 cost to complete funding is for
“Program increase: FY 2021 DDG 51s SEWIP [Surface Electronic Warfare Improvement
Program] Block III.” (Page 135)

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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.24 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,25 to improve the Navy’s general capabilities for operating in defended littoral
waters, and to introduce several new technologies that would be available for use on future Navy

24 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.
25 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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ships. The DDG-1000 was also intended to serve as the basis for a planned cruiser called CG(X)
that was subsequently canceled.26
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 system27 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 FY2024 budget submission estimates their
combined procurement cost at $9,450.8 million. The third DDG-1000 was procured in FY2009
and split-funded in FY2009-FY2010; the Navy’s FY2024 budget submission estimates its
procurement cost at $4,342.4 million.
The first DDG-1000 was commissioned into service on September 7, 2016. Its delivery date was
revised multiple times and reportedly was April 2020.28 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.29 In the
Navy’s FY2024 budget submission, the delivery dates for the two ships are listed as October 2023
and December 2026, respectively.
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:30

26 For more on the CG(X) program, see CRS Report RL34179, Navy CG(X) Cruiser Program: Background for
Congress, by Ronald O'Rourke.
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.
28 See Aidan Quigley, “Final Delivery of Zumwalt-class Destroyer Monsoor Delayed,” Inside Defense, January 21,
2021.
29 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.
30 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-
(continued...)
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• 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.31
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.32
New Technologies
The DDG-1000 incorporates a significant number of new technologies, including a wave-
piercing, tumblehome hull design for reduced detectability,33 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,34 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).
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/Ingalls35 and
GD/BIW.

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).
31 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.
32 For more on Navy ship names, see CRS Report RS22478, Navy Ship Names: Background for Congress, by Ronald
O'Rourke.
33 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.
34 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.
35 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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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,
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.36
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

36 Christopher P. Cavas, “Will Bath Build Second DDG 1000?” Defense News, January 12, 2009: 1, 6.
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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).37
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 submissions, has grown by $4,816.1 million (i.e.,
about $4.8 billion), or 53.6%, since the FY2009 budget (i.e., the budget for the fiscal year in
which the third DDG-1000 was procured). Within the increase from the FY2023 figure to the
FY2024 figure, the Navy’s FY2024 budget submission states $234 million is for modifying the
third ship in the program (DDG-1002) during its construction to include large-diameter vertical
launch tubes capable of storing and firing the Navy’s new hypersonic Conventional Prompt Strike
(CPS) missile.38 (Costs to modify the first two DDG-1000 class ships—DDG-1000 and DDG-
1001—for the CPS are budgeted in the Other Procurement, Navy [OPN] appropriation account.)

37 For additional discussion, see CRS Report R43838, 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.
38 Department of Defense, Fiscal Year (FY) 2024 Budget Estimates, Navy Justification Book Volume 1 of 1,
Shipbuilding and Conversion, Navy, March 2023, pp. 178-179.
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Table A-1. Estimated Combined Procurement Cost of DDGs 1000, 1001, and 1002
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%)
FY22
13,305.9
+30.3 (+0.2+%)
+4,328.8 (+48.2%)
FY23
13,378.7
+72.8 (+0.5%)
+4,401.6 (+49.0%)
FY24
13,793.2
+414.5 (+3.1%)
+4,816.1 (+53.6%)
Source: Table prepared by CRS based on data in annual Navy budget submissions.
Note: The Navy’s FY2024 budget submission states $234 mil ion of the increase shown for FY2024 is for
modifying the third ship in the program (DDG-1002) during its construction to include large-diameter vertical
launch tubes capable of storing and firing the Navy’s new hypersonic Conventional Prompt Strike (CPS) missile.
(Costs to modify the first two DDG-1000 class ships—DDG-1000 and DDG-1001—for the CPS are budgeted in
the Other Procurement, Navy [OPN] appropriation account.)
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 stated in 2014 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.39
Technical Risk and Test and Evaluation Issues
June 2023 GAO Report
A June 2023 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 yet to mature a total of four critical technologies despite
completing construction of the third and final ship of the class in 2021. Three of these
immature technologies, which involve the ships’ signature, computing, and radar
capabilities, were planned since program start. According to the program, the Navy intends
to demonstrate full maturity for these technologies during operational testing.
However, two more recently identified critical technologies—one of which the Navy has
yet to mature—face installation delays. As we reported in our last assessment, a
communication system and an intelligence system were added to the program in 2020 to
enable the new surface strike mission. The program office stated that the Chief of Naval
Operations directed a delayed installation of these systems on Zumwalt class ships to shift
the program’s focus to integrating the Navy’s new Conventional Prompt Strike (CPS)
hypersonic weapon system. We evaluate the CPS program in a separate assessment in this
report.
The Navy plans to complete operational testing on DDG 1000 in December 2023—a 12-
month delay compared with the schedule during last year’s assessment. According to the
program office, weather, limited ship availability for testing, and test range and asset
limitations contributed to this delay.
Further, the Navy delayed initial operational capability for DDG 1000 an additional 4
months during the past year. Initial operational capability is now planned for April 2023—
over 6 years later than the program’s approved acquisition program baseline date.
The other two ships continue to face delivery delays. DDG 1001 final delivery was delayed
12 months to September 2023. While the program is working toward the completion of
combat systems installation and activation for the DDG 1002, program officials stated that
DDG 1002 final delivery moved from fiscal year 2024 to early fiscal year 2025.
Other Program Issues
The Navy requested approximately $160 million in research, development, test and
evaluation funds across fiscal years 2022 and 2023 to support the CPS hypersonic weapon
system’s incorporation into DDG 1000 class ships. According to the program, it continued
engineering design planning to support CPS integration initiated last year. This includes
plans to replace the ship’s advanced gun system with the CPS hypersonic weapon. The
Navy plans to install the hypersonic weapon system on the DDG 1000 during a
maintenance period in fiscal year 2024.
According to the program, the start of the maintenance period and hypersonic weapon
system installation on DDG 1000 will not be affected if operational testing—now
scheduled to take place immediately prior to the maintenance period—is not completed as
planned. The program stated that, in the event that operational testing is delayed until a

39 Source: Navy briefing for CRS and the Congressional Budget Office (CBO) on the DDG-1000 program, April 30,
2014.
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date during DDG 1000’s scheduled maintenance period, the DDG 1001 would be used for
the testing instead.
However, the CPS program office noted that significant scope and challenges associated
with the first-time integration of CPS may present risks to achieving DDG 1000’s
installation schedule. In reviewing CPS program office information on critical
technologies, we found that significant work remains for the program to demonstrate
technology maturity. DDG 1000 program officials stated that they are closely monitoring
the delivery of CPS hypersonic weapon missile tubes and both program offices are working
to mitigate any risks to ensure the timely integration of CPS into Zumwalt class ships.
However, if the hypersonic weapon is not ready for integration on the DDG 1000 at the
time of the aforementioned maintenance period, the Navy may have to extend the duration
of the planned maintenance period or wait for the next scheduled period to incorporate the
system on the ship.
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 program office stated that it is making significant progress in construction, testing,
activation, and sustainment of the Zumwalt class ships. It noted that DDG 1000 completed
radar signature and anti-air warfare testing as well as a special trial conducted by the Navy
Board of Inspection and Survey. It added that the DDG 1000 participated in operations
from August 2022 to November 2022. For DDG 1001, the program office stated that the
ship participated in aviation and survivability test events and fleet exercises. Further, the
program office noted that DDG 1002 is currently undergoing combat systems installation
and activation at Huntington Ingalls Industries’ Pascagoula, MS shipyard. According to the
program office, the Zumwalt class is on track to be the first platform to field a long-range
precision hypersonic capability by integrating the CPS weapon system.40
January 2023 DOT&E Report
A January 2023 report from DOD’s Director, Operational Test and Evaluation (DOT&E)—
DOT&E’s annual report for FY2022—stated the following regarding the DDG-1000 program:
TEST ADEQUACY
DDG 1000 testing to date was conducted in accordance with the DOT&E-approved test
plan, observed by DOT&E, and progressed towards an adequate collection of data to
support operational effectiveness and suitability assessments. FY22 testing assessed Anti-
Submarine Warfare (ASW), SUW [surface warfare], and Anti-Air Warfare (AAW).
• ASW: USS Michael Monsoor executed Torpedo Defense testing in October 2021 in
Nanoose Bay, Canada. Testing of the ship’s ASW capability against a submarine was
postponed.
• SUW: USS Zumwalt executed SUW testing in November and December 2021 in the
Southern California operational area. The SUW operational test (OT) is complete and
adequate for DOT&E to make an assessment.
• AAW: USS Zumwalt performed six integrated developmental/operational test events and
an OT event in 2Q/3QFY22 [second quarter/third quarter of FY2022] that were adequate
to support DOT&E’s AAW assessment. The Navy intends to conduct additional AAW OT
events in FY24. The Navy continues to develop the combat system modeling and

40 Government Accountability Office, Weapon Systems Annual Assessment[:] Programs Are Not Consistently
Implementing Practices That Can Help Accelerate Acquisitions, GAO-23-106059, June 2023, p. 144.
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simulation (M&S) test bed, which is required to complete OT. The Navy expects to
commence AAW M&S testing in FY24.
Cyber survivability testing is planned in FY23 on USS Zumwalt. Strike Warfare
operational testing is targeted in FY23 and FY24 on USS Michael Monsoor. The Navy is
developing an OASuW [Offensive Anti-Surface Warfare] operational test strategy for
DOT&E approval in the next TEMP [Test and Evaluation master Plan] revision.
The Navy has not funded or planned an adequate ship survivability assessment against
underwater threat weapons, to include a demonstration of residual mission capability after
such engagements, through a full-ship shock trial. This assessment was not complete prior
to initial deployment of USS Zumwalt in 4QFY22 [fourth quarter of FY2022]. DOT&E
issued an Early Fielding Report in November 2022.
The Navy has not updated vulnerability and recoverability M&S meant to support the
LFT&E [Live Fire Test and Evaluation] survivability assessment of the DDG 1000 class
to reflect the ship as built. Further, the Navy does not intend to update, validate, or accredit
LFT&E survivability assessments prior to completing their LFT&E program in FY23.
DOT&E will not be able to provide an assessment of the Zumwalt class’s vulnerability to
threat weapons without the results from validated survivability M&S that models the ship
design as built.
In FY22, the Navy completed a series of Failure and Recoverability Mode (FARM) tests
aboard USS Michael Monsoor to assess the capability of the class’s mission systems to
recover from system failures and to determine the effectiveness of damage control
response. The scope of these tests were limited due to ongoing installation of Zumwalt-
class mission systems and communication systems, as well as software updates and
availability of auxiliary equipment due to ongoing maintenance.
Despite the test limitations, FARM testing provided valuable insight into how integrated
systems and software respond to non-standard operating environments that can result from
battle damage.
PERFORMANCE
EFFECTIVENESS
Not enough data are yet available to provide a preliminary assessment of DDG 1000
operational effectiveness. The AAW live missile events conducted on the DDG 1000 and
previously on the Self Defense Test Ship highlighted performance limitations that may
restrict operational effectiveness in the AAW mission. Final assessment of Zumwalt-class
offensive surface strike effectiveness will be reported in a classified report following the
completion of the live missile events in FY27. DOT&E issued an Early Fielding Report in
November 2022 due to the Navy’s deployment of USS Zumwalt in 4QFY22.
SUITABILITY
Not enough data are yet available to provide a preliminary assessment of Zumwalt-class
operational suitability.
SURVIVABILITY
Due to vulnerability and recoverability M&S not yet being validated or reflecting the ship
as-built, data are insufficient to assess Zumwalt-class survivability against threat weapons.
Further, no data are yet available to assess DDG 1000 in a cyber-contested environment.
FARM testing aboard DDG 1001 identified equipment responses that were previously
unknown. The Navy will evaluate potential changes as part of class modernization and
sustainment.
RECOMMENDATIONS
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The Navy should:
1. Complete IOT&E [Initial Operational Test and Evaluation] in accordance with the
DOT&E-approved test plan.
2. Complete revision of the TEMP that includes an adequate test strategy for the delivered
OASuW capability.
3. Complete development and validate the combat system M&S test bed, to include debris,
missile, radar, and electronic warfare models.
4. Document the risk to the warfighter associated with incomplete component shock
qualification and lack of full-ship shock trial prior to deployment.
5. Work with DOT&E to develop an updated LFT&E strategy in FY23 to evaluate the as-
built survivability of the DDG 1000 class with the next TEMP update, including updated
survivability M&S and remaining shipboard testing.
6. Sufficiently fund modernization and sustainment of the DDG 1000 class to include
improvements determined from FARM testing.41
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
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.42
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.43 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

41 Department of Defense, Director, Operational Test and Evaluation, FY2022 Annual Report, January 2023, pp. 173-
174.
42 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.
43 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.
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acquisition unit cost (PAUC)—one of two measures used under the Nunn-McCurdy provision for
measuring cost growth44—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.45 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
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.46
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

44 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.
45 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.
46 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.
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the cost to integrate the dual-band radar into the Navy’s new Gerald R. Ford (CVN-78) class
aircraft carriers.47 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.”48
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
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-1000.49

47 Source: Undated Navy information paper on CVN-78 cost issues, provided by Navy Office of Legislative Affairs to
CRS on March 19, 2012.
48 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.
49 Christopher J. Castelli, “Pentagon Approves Key Milestone For Multibillion-Dollar Destroyer,” Inside the Navy,
November 22, 2010.
Congressional Research Service

27

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

Author Information

Ronald O'Rourke

Specialist in Naval Affairs

Disclaimer
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Congressional Research Service
RL32109 · VERSION 268 · UPDATED
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