Navy DDG-51 and DDG-1000 Destroyer
Programs: Background and Issues for
Congress
Updated June 4, 2021
Congressional Research Service
https://crsreports.congress.gov
RL32109

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

Summary
The Navy began procuring Arleigh Burke (DDG-51) class destroyers, also known as Aegis
destroyers, in FY1985, and a total of 87 have been procured through FY2021, including two in
FY2021. From FY1989 through FY2005, DDG-51s were procured in annual quantities of two to
five ships per year. Since FY2010, they have been procured in annual quantities of one to three
ships per year.
DDG-51s are being procured in FY2018-FY2022 under a multiyear procurement (MYP) contract
that Congress approved as part of its action on the Navy’s FY2018 budget. DDG-51s procured in
FY2017 and subsequent years are being built to a design cal ed the Flight III design, which
incorporates a new and more capable radar cal ed the SPY-6 radar.
The Navy’s proposed FY2022 budget requests the procurement of one DDG-51 in FY2022,
rather than the two DDG-51s that are cal ed for FY2022 under the FY2018-FY2022 DDG-51
MYP contract, and that were projected for FY2022 under the Navy’s FY2021 budget submission.
A key issue for Congress for the DDG-51 program in FY2022 is whether to fund the procurement
of one DDG-51, two DDG-51s, or some other number of DDG-51s (such as zero or three).
When procured at a rate of two per year, DDG-51s cost roughly $2.0 bil ion each. Due to the
reduced production economies of scale that would occur at a production rate of one ship per year,
the one DDG-51 requested for procurement in FY2022 has an estimated cost of $2,401.7 mil ion
(i.e., about $2.4 bil ion). Under the Navy’s proposed FY2022 budget, the one requested DDG-51
would receive $384.9 mil ion in prior-year Economic Order Quantity (EOQ) funding—a type of
advance procurement (AP) funding that occurs under an MYP contract. Taking this prior-year
EOQ funding into account, the Navy’s proposed FY2022 budget requests the remaining $2,016.8
mil ion (i.e., about $2.0 bil ion) needed to complete the ship’s estimated procurement cost of
$2,401.7 mil ion. The Navy’s proposed FY2022 budget also requests $45.8 mil ion in cost-to-
complete funding to pay for cost growth on DDG-51s procured in prior years, bringing the total
amount of procurement funding requested for the DDG-51 program to $2,062.5 mil ion (i.e.,
about $2.1 bil ion)
Procuring one DDG-51 rather than two DDG-51s in FY2022 would prevent the Navy from
fulfil ing its obligations in the final year of the FY2018-FY2022 DDG-51 MYP contract. Navy
officials state that as a result, the Navy would need to pay a $33 mil ion penalty to the DDG-51
shipbuilders (unless the Navy and the shipbuilders were to reach an agreement to amend the
terms of the MYP contract).
Navy officials have stated that requesting procurement of one DDG-51 rather than two DDG-51s
was an affordability measure—a means of helping the Navy remain within its budget topline
while meeting funding needs for other Navy programs. Procuring a second DDG-51 in FY2022 is
the number one item on the Navy’s FY2022 Unfunded Priorities List (UPL)—the service’s list of
programs it would prefer to be funded in FY2022, if additional funding were to become available.
The UPL states that procuring two DDG-51s rather than one DDG-51 in FY2022 would require
an additional $1,659.2 mil ion (i.e., about $1.7 bil ion) in shipbuilding funding. That figure is not
the cost of the second DDG-51—the second DDG-51’s procurement cost would be roughly $2.0
bil ion. Adding the second DDG-51, however, would reduce the estimated procurement cost of
the first DDG-51 due to the resulting increased production economies of scale. The figure of
$1,659.2 mil ion is thus the net increase in shipbuilding funding that would be needed to procure
two DDG-51s rather than one DDG-51 in FY2022.
Congressional Research Service

link to page 26 Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress

Contacts
Author Information ....................................................................................................... 22

Congressional Research Service

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

Introduction
This report presents background information and potential oversight issues for Congress on the
Navy’s Arleigh Burke (DDG-51) and Zumwalt (DDG-1000) class destroyer programs. The Navy
began procuring DDG-51s, also known as Aegis destroyers, in FY1985, and a total of 87 have
been procured through FY2021, including two in FY2021. The Navy procured three DDG-1000
class destroyers in FY2007-FY2009 and plans no further procurement of DDG-1000s.
The Navy’s proposed FY2022 budget requests the procurement of one DDG-51 in FY2022,
rather than the two DDG-51s that are cal ed for FY2022 under the FY2018-FY2022 DDG-51
multiyear procurement (MYP) contract, and that were projected for FY2022 under the Navy’s
FY2021 budget submission. Procuring a second DDG-51 in FY2022 is the number 1 item on the
Navy’s FY2022 Unfunded Priorities List (UPL)—the service’s list of programs it would prefer to
be funded in FY2022, if additional funding were to become available. A key issue for Congress
for the DDG-51 program in FY2022 is whether to fund the procurement of one DDG-51, two
DDG-51s, or some other number of DDG-51s (such as zero or three).
Other issues for Congress concern the Navy’s future force-level goal for large surface combatants
(or LSCs, meaning cruisers and destroyers), the DDG-51 procurement rate in FY2023 and
subsequent fiscal years, and how the Navy proposes to transition several years from now from
procurement of DDG-51s to procurement of a successor destroyer design now in development
cal ed the DDG(X). Decisions that Congress makes on these issues could substantial y affect
Navy capabilities and funding requirements, and the U.S. shipbuilding industrial base.
For more on the DDG(X) program, see CRS In Focus IF11679, Navy DDG(X) Future Large
Surface Combatant Program: Background and Issues for Congress, by Ronald O'Rourke.
Background
Navy’s Force of Large Surface Combatants (LSCs)
LSC Definition
Decades ago, the Navy’s cruisers were considerably larger and more capable than its destroyers.
In the years after World War II, however, the Navy’s cruiser designs in general became smal er
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

1 T he Navy sometimes also uses the term Cru-Des (an abbreviation of cruiser-destroyer, pronounced “crew-dez”) to
refer collectively to its cruisers and destroyers.
Congressional Research Service

1

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

LSC Force Levels
Current Force-Level Goal
The Navy’s current force-level goal, released in December 2016, cal s for achieving and
maintaining a fleet of 355 ships, including 104 LSCs.2
Potential New Force-Level Goal
The Navy and the Department of Defense (DOD) have been working since 2019 to develop a
successor for the 355-ship force-level goal. On December 9, 2020, the outgoing Trump
Administration released a document that can be viewed as its own vision for future Navy force
structure and/or a draft version of the FY2022 30-year Navy shipbuilding plan. The document
presents an envisioned Navy force-level goal for achieving by 2045 a Navy with a more
distributed fleet architecture, including 382 to 446 manned ships and 143 to 242 large unmanned
vehicles. Within the total of 382 to 446 manned ships, the document cal s for maintaining a force
of 73 to 88 LSCs. In determining its Navy force-level goals and shipbuilding plans, the Biden
Administration can choose to adopt, revise, or set aside this document.3
Actual Force Level as of End of FY2020
As of the end of FY2020, the Navy’s force of LSC’s included 91 LSCs, including 22 Ticonderoga
(CG-47) class cruisers,4 68 DDG-51s, and one Zumwalt (DDG-1000) class destroyer.
DDG-51 Program
Overview
The DDG-51 program was initiated in the late 1970s.5 The first DDG-51 was procured in FY1985
and entered service in 1991. A total of 87 DDG-51s have been procured through FY2021,
including two in FY2021. From FY1989 through FY2005, DDG-51s were procured in annual
quantities of two to five ships per year. Since FY2010, they have been procured in annual
quantities of one to three ships per year. (The Navy did not procure any DDG-51s during the
period FY2006-FY2009. Instead, the Navy in FY2007-FY2009 procured three Zumwalt [DDG-
1000] class destroyers, which are discussed later in this report.) The DDG-51 program is one of
the longest-running shipbuilding programs in Navy history, and the DDG-51 class, in terms of
number of hulls, is one of the Navy’s largest classes of ships since World War II.

2 For more on the 355-ship force-level goal, see CRS Report RL32665, Navy Force Structure and Shipbuilding Plans:
Background and Issues for Congress, by Ronald O'Rourke.
3 For more on the December 9, 2020 document, see CRS Report RL32665, Navy Force Structure and Shipbuilding
Plans: Background and Issues for Congress, by Ronald O'Rourke.
4 A total of 27 CG-47s (CGs 47 through 73) were procured for the Navy between FY1978 and FY1988; the ships
entered service between 1983 and 1994. T he first five ships in the class (CGs 47 through 51), which were built to an
earlier technical standard in certain respects, were judged by the Navy to be too expensive to modernize and were
removed from service in 2004-2005, leaving 22 ships in operation (CGs 52 through 73).
5 T he 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. T he DDG-51 was conceived as an affordable complement to the Navy’s
T iconderoga (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.
Congressional Research Service

2

link to page 7

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

DDG-51s (Figure 1) are multi-mission destroyers with an emphasis on air defense (which the
Navy refers to as anti-air warfare, or AAW) and blue-water (mid-ocean) operations. DDG-51s,
like the Navy’s 22 Ticonderoga (CG-47) class cruisers, are equipped with the Aegis combat
system, an integrated ship combat system named for the mythological shield that defended Zeus.
CG-47s and DDG-51s consequently are often referred to as Aegis cruisers and Aegis destroyers,
respectively, or collectively as Aegis ships. The Aegis system has been updated several times over
the years. Many DDG-51s (and also some CG-47s) have a capability for conducting bal istic
missile defense (BMD) operations.6
Figure 1. DDG-51 Class Destroyer

Source: U.S. Navy file photograph.
Design Changes
The DDG-51 design has been modified and updated periodical y over the years. The first 28
DDG-51s (DDGs 51 through 78) are cal ed 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 Flight III DDG-51 design, which incorporates a new and more
capable radar cal ed the SPY-6 radar or the Air and Missile Defense Radar (AMDR), as wel 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.

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.
Congressional Research Service

3

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

Multiyear Procurement (MYP)
As part of its action on the Navy’s FY2018 budget, Congress granted the Navy authority to use a
multiyear procurement (MYP) contract for DDG-51s planned for procurement in FY2018-
FY2022. This is the fourth MYP contract for the DDG-51 program—previous DDG-51 MYP
contracts covered DDG-51s procured in FY2013-FY2017, FY2002-FY2005, and FY1998-
FY2001.
Shipbuilders, Combat System Lead, and Radar Makers
DDG-51s are built by General Dynamics/Bath Iron Works (GD/BIW) of Bath, ME, and
Huntington Ingal s Industries/Ingal s Shipbuilding (HII/Ingal s) of Pascagoula, MS. Lockheed is
the lead contractor for the Aegis system instal ed on al 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.7
FY2022 Procurement Funding Request
The Navy’s proposed FY2022 budget requests the procurement of one DDG-51 in FY2022,
rather than the two DDG-51s that are cal ed for FY2022 under the FY2018-FY2022 DDG-51
MYP contract, and that were projected for FY2022 under the Navy’s FY2021 budget submission.
When procured at a rate of two per year, DDG-51s cost roughly $2.0 bil ion each. Due to the
reduced production economies of scale that would occur at a production rate of one ship per year,
the one DDG-51 requested for procurement in FY2022 has an estimated cost of $2,401.7 mil ion
(i.e., about $2.4 bil ion).
Under the Navy’s proposed FY2022 budget, the one requested DDG-51 would receive $384.9
mil ion in prior-year Economic Order Quantity (EOQ) funding—a type of advance procurement
(AP) funding that occurs under an MYP contract.8 Taking this prior-year EOQ funding into
account, the Navy’s proposed FY2022 budget requests the remaining $2,016.8 mil ion (i.e., about
$2.0 bil ion) needed to complete the ship’s estimated procurement cost of $2,401.7 mil ion. The
Navy’s proposed FY2022 budget also requests $45.8 mil ion in cost-to-complete funding to pay
for cost growth on DDG-51s procured in prior years, bringing the total amount of procurement
funding requested for the DDG-51 program to $2,062.5 mil ion (i.e., about $2.1 bil ion)
Procuring one DDG-51 rather than two DDG-51s in FY2022 would prevent the Navy from
fulfil ing its obligations in the final year of the FY2018-FY2022 DDG-51 MYP contract. Navy
officials state that as a result, the Navy would need to pay a $33 mil ion penalty to the DDG-51

7 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 Com parison With
An Equal-Cost Force Of Ticonderoga (CG-47) Class Guided Missile Destroyers, by Ronald O’Rourke (November 21,
1984; out of print and available to congressional clients directly from the author).
8 For more on EOQ funding with MYP contracts, see CRS Report R41909, Multiyear Procurement (MYP) and Block
Buy Contracting in Defense Acquisition: Background and Issues for Congress, by Ronald O'Rourke.
Congressional Research Service

4

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

shipbuilders9 (unless the Navy and the shipbuilders were to reach an agreement to amend the
terms of the MYP contract).
Navy officials have stated that requesting procurement of one DDG-51 rather than two DDG-51s
was an affordability measure—a means of helping the Navy remain within its budget topline
while meeting funding needs for other Navy programs. Procuring a second DDG-51 in FY2022 is
the number one item on the Navy’s FY2022 Unfunded Priorities List (UPL)—the service’s list of
programs it would prefer to be funded in FY2022, if additional funding were to become available.
The UPL states that procuring two DDG-51s rather than one DDG-51 in FY2022 would require
an additional $1,659.2 mil ion (i.e., about $1.7 bil ion) in shipbuilding funding. That figure is not
the cost of the second DDG-51—the second DDG-51’s procurement cost would be roughly $2.0
bil ion. Adding the second DDG-51, however, would reduce the estimated procurement cost of
the first DDG-51 due to the resulting increased production economies of scale. The figure of
$1,659.2 mil ion is thus the net increase in shipbuilding funding that would be needed to procure
two DDG-51s rather than one DDG-51 in FY2022.
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 original y 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. Consistent with that mission
orientation, the ship was designed with two new-design 155mm guns cal ed Advanced Gun
Systems (AGSs). The AGSs were to fire a new 155mm, gun-launched, rocket-assisted guided
projectile cal ed 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 $800,000.10
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 wil be shifted
from an emphasis on NSFS to an emphasis on surface strike, meaning the use of missiles to attack
surface ships and perhaps also land targets.11
In April and May 2021, it was reported that the Navy plans to remove the AGSs on the three ships
and replace them with vertical launch tubes for the Navy’s new hypersonic Conventional Prompt
Strike (CPS) missile, with a goal of fielding CPSs on a DDG-1000 class ship by 2025.12

9 See, for example, Christopher P. Cavas, “ Updated: Fleet Growth Stymied by Navy Budget Request ,” USNI News,
May 28 (updated May 30), 2021.
10 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, “T he Navy Called USS Zumwalt A Warship Batman Would Drive. But at $800,000 Per Round, Its
Ammo Is T oo Pricey to Fire,” Washington Post, November 8, 2016.
11 Megan Eckstein, “New Requirements for DDG-1000 Focus on Surface Strike,” USNI News, December 4, 2017. See
also Richard Abott, “Navy Will Focus Zumwalt On Offensive Surface Strike,” Defense Daily, December 5, 2017;
David B. Larter, “T he Navy’s Stealth Destroyers to Get New Weapons and a New Mission: Killing Ships,” Defense
News, February 15, 2018.
12 See, for example, Sam LaGrone, “ CNO: Hypersonic Weapons at Sea to Premiere on Zumwalt Destroyers in 2025 ,”
USNI News, April 28, 2021; Jason Sherman, “ Navy to Rip Out DDG-1000 Advanced Gun System Mounts to Make
Congressional Research Service

5

link to page 16 Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress

For additional background information on the DDG-1000 program, see the Appendix.
Surface Combatant Construction Industrial Base
Al cruisers and destroyers procured since FY1985 have been built at GD/BIW and HII/Ingal s.
Both of these shipyards have long histories of building larger surface combatants. Construction of
Navy surface combatants in recent years has accounted for virtual y al of GD/BIW’s ship-
construction work and for a significant share of HII/Ingal s’ ship-construction work. (HII/Ingal s
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/Ingal s, and other U.S.
shipyards.
Lockheed Martin and Raytheon are general y 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 cal ed the Total Ship Computing Environment Infrastructure
(TSCE-I). Lockheed has a share of the DDG-1000 combat system, and Raytheon has a share of
the DDG-51 combat system. Lockheed, Raytheon, and Northrop competed to be the maker of the
AMDR to be carried by the Flight III DDG-51. On October 10, 2013, the Navy announced that it
had selected Raytheon to be the maker of the AMDR, now cal ed the SPY-6 radar.
The surface combatant construction industrial base also includes hundreds of additional firms that
supply materials and components. The financial health of Navy shipbuilding supplier firms has
been a matter of concern in recent years, particularly since some of them are the sole sources for
what they make for Navy surface combatants. Several Navy-operated laboratories and other
facilities support the Aegis system and other aspects of the DDG-51 and DDG-1000 programs.
Issues for Congress
Number of DDG-51s to Procure in FY2022
A key issue for Congress for the DDG-51 program in FY2022 is whether to fund the procurement
of one DDG-51, two DDG-51s, or some other number of DDG-51s (such as zero or three).
Supporters of procuring one DDG-51 might argue that in a situation of finite defense resources,
funding the procurement of two DDG-51s could require reducing funding for other Navy or DOD
programs by about $1.7 bil ion, which could reduce Navy or DOD capabilities in other ways; that
the Navy’s new fleet architecture may result in a reduction in the force-level goal for large
surface combatants; and that the DDG-51 industrial base (both shipyards and supplier firms) wil
be adequately supported by their existing backlog of DDG-51s and other Navy shipbuilding
work.
Supporters of procuring two DDG-51s might argue that it would help accelerate the introduction
of Flight III DDG-51s, with their SPY-6 radars, into the fleet; that it would improve production

Room for Hypersonic Weapons,” Inside Defense, May 26, 2021. See also Paul McLeary, “ Exclusive[:] Eying China,
CNO Plans Hypersonics & Lasers On Zumwalt Destroyers,” Breaking Defense, February 26, 2021; Joseph T revithick,
“Navy Wants T riple-Packed Hypersonic Missile Modules On Its Stealthy Zumwalt Destroyers,” The Drive, March 19,
2021; David B. Larter, “ What Should Become of the Zumwalt Class? T he US Navy Has Some Big Ideas,” Defense
News, March 25, 2021.
For more on the CPS program, see CRS Report R41464, Conventional Prom pt Global Strike and Long -Range Ballistic
Missiles: Background and Issues, by Amy F. Woolf.
Congressional Research Service

6

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

economies of scale in the DDG-51 program; and that it would more strongly support the DDG-51
industrial base. The second DDG-51’s position at the top of the Navy’s FY2022 UPL, they might
argue, shows that the second ship is a high-priority item for the Navy to fund with offsetting
reductions that Congress might be able to identify in reviewing and marking up DOD’s proposed
FY2022 budget.
Future LSC Force-Level Goal
Another issue for Congress concerns the future LSC force-level goal. In connection with this
issue, it can be noted that, compared to the Navy’s current force-level goal for a fleet of 355
ships, including 104 LSCs, the December 9, 2020, shipbuilding document released by the
outgoing Trump Administration cal s for a larger total number of manned ships (382 to 446) but a
smal er number of LSCs (73 to 88). This is because the December 9, 2020, shipbuilding
document proposes shifting the Navy to a more distributed force architecture that would feature
 a smal er proportion of larger ships (such as large-deck aircraft carriers, cruisers,
destroyers, large amphibious ships, and large resupply ships);
 a larger proportion of smal er ships (such as frigates, corvettes, smal er
amphibious ships, smal er resupply ships, and perhaps smal er aircraft carriers);
and
 a new third tier of surface vessels about as large as corvettes or large patrol craft
that wil be either lightly manned, optional y manned, or unmanned, as wel as
large unmanned underwater vehicles (UUVs).
Navy and DOD leaders believe that shifting to a more distributed fleet architecture is
 operationally necessary, to respond effectively to the improving maritime anti-
access/area-denial (A2/AD) capabilities of other countries, particularly China;
 technically feasible as a result of advances in technologies for unmanned
vehicles (UVs) and for networking widely distributed maritime forces that
include significant numbers of UVs; and
 affordable—no more expensive, and possibly less expensive, than the current
fleet architecture, for a given aggregate level of Navy capability.13
Reducing the LSC force-level goal from 104 ships to a smal er number could affect issues such as
when to retire older LSCs and how many new LSCs to procure each year.
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

13 For additional discussion about shifting the Navy to a more distributed architecture, see CRS Report RL32665, Navy
Force Structure and Shipbuilding Plans: Background and Issues for Congress, by Ronald O'Rourke.
Congressional Research Service

7

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

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.
Future DDG-51 Procurement Rate and Transition to DDG(X)
Another issue for Congress concerns the DDG-51 procurement rate in FY2023 and subsequent
fiscal years, and how the Navy proposes to transition several years from now from procurement
of DDG-51s to procurement of a successor destroyer design now in development cal ed the
DDG(X). Navy plans for transitioning from procurement of DDG-51s to procurement of
DDG(X)s were an oversight focus for the defense committees in their reviews and markups of the
Navy’s proposed FY2020 and FY2021 budgets. Decisions regarding the future DDG-51
procurement rate and the transition to DDG(X) procurement wil affect Navy capabilities and
funding requirements and the U.S. shipbuilding industrial base. Recent documents have shown
the following:
 The Navy’s FY2020 budget submission and FY2020 30-year shipbuilding plan
projected DDG-51s being procured during the period FY2022-FY2025 in annual
quantities of 2-3-3-2, with FY2025 being the final year of DDG-51 procurement
and the year that the first DDG(X) would be procured.
 The Navy’s FY2021 budget submission projected DDG-51s being procured
during the period FY2022-FY2025 in annual quantities of 2-1-2-1, and for DDG-
51 procurement to end with the procurement of two final ships that would be
procured in either FY2026 (both ships) or FY2026 and FY2027 (one ship each
year). Under this budget submission, DDG(X) procurement might begin around
FY2028.
 The December 9, 2020, document released by the outgoing Trump
Administration projected DDG-51s being procured during the period FY2022-
FY2026 in annual quantities of 2-2-2-2-2. The document did not specify the final
year of DDG-51 procurement, but press reports suggest that the Navy wants to
procure the first DDG(X) around FY2028.
For more on the DDG(X) program, see CRS In Focus IF11679, Navy DDG(X) Future Large
Surface Combatant Program: Background and Issues for Congress, by Ronald O'Rourke.
Congressional Research Service

8

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

Potential Impact of COVID-19 Pandemic
Another issue for Congress concerns the potential impact of the COVID-19 pandemic on the
execution of U.S. military shipbuilding programs, including the DDG-51 program. For additional
discussion of this issue, see CRS Report RL32665, Navy Force Structure and Shipbuilding Plans:
Background and Issues for Congress, by Ronald O'Rourke.
Cost, Technical, and Schedule Risk in Flight III DDG-51 Effort
Another issue for Congress concerns cost, technical, and schedule risk for the Flight III DDG-51.
A June 2020 Government Accountability Office (GAO) report assessing selected DOD
acquisition programs stated the following in its assessment of the Flight III DDG-51:
Current Status
Flight III ships include considerable changes to DDG 51’s design to incorporate the
AN/SPY-6(V)1 radar and restore ship weight and stability safety margins. The program
delayed the start of power and integration testing for the AN/SPY-6(V)1 radar from
January 2019 to April 2020 due to software-related deficiencies that, according to program
officials, are now resolved. Despite this delay, the Navy plans to deliver equipment,
complete testing and installation on the ship, and activate the combat system for shipboard
testing by January 2022. Further, it expects both the radar and software developed for the
ship’s combat system to be delivered before the power and integration testing is completed
at the combat system development site, limiting opportunities to fix any issues prior to
activation.
The Navy plans to complete an integrated test and evaluation master plan for the ship,
AN/SPY-6(V)1 radar, and the Aegis combat system by the time of combat system
activation in January 2022. The plan, according to Navy officials, will not include the use
of an unmanned self-defense test ship, although DOD’s Director, Operational Test and
Evaluation and the Navy previously disagreed on whether an unmanned ship was necessary
to validate the end-to-end performance of Flight III ships —including the self-defense
capability—during operational testing.
The Navy continues construction on the lead Flight III ship, DDG 125, with plans for
delivery in fiscal year 2023. Construction of the second ship is planned to start in April
2020. Officials report that the Navy has procured 11 ships using multiyear procurement
authority and plans to award a contract for a 12th ship in fiscal year 2020. The current
acquisition strategy includes 22 ships but, according to Navy officials, the total number of
Flight III ships depends on the Navy’s plans for its future large surface combatant ships.
Program Office Comments
We provided a draft of this assessment to the program office for review and co mment. The
program office provided technical comments, which we incorporated where appropriate.
The program stated it has delivered 67 ships and is on track for delivery and initial
capability of the first Flight III ship. According to the program, it rebaselined the radar test
and delivery schedule to better align production and testing and is on track to complete
radar testing prior to the start of shipboard testing. Further, the program said the
development of the radar and software are on track to support integration.14
Regarding the AMDR specifical y, the report stated the following:
Technology Maturity, Design Stability, and Production Readiness

14 Government Accountability Office, Defense Acquisitions Annual Assessment[:] Drive to Deliver Capabilities Faster
Increases Im portance of Program Knowledge and Consistent Data for Oversight, GAO-20-439, June 2020 p. 145.
Congressional Research Service

9

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

In April 2019, the Navy approved AMDR to procure its 10th low-rate initial production
radar in fiscal year 2020. According to the program, it has mature critical technologies, a
stable design, and production processes in control. However, we continue to disagree that
the technologies are fully mature. While the Navy continues to demonstrate some
technologies through land-based testing at its Pacific Missile Range Facility (PMRF) and
plans to integrate AMDR with the Aegis combat system at a separate land-based site for
simulation and testing, AMDR’s critical technologies cannot be assessed as fully mature
until the Navy integrates AMDR and Aegis on the lead DDG 51 Flight III ship in 2022
during the Aegis Light Off (ALO) event. Following ALO, the Navy will operationally test
AMDR and Aegis in a realistic, at-sea environment on the lead DDG 51 Flight III ship in
2023. While AMDR’s design is currently stable, it remains at risk for disruption until the
Navy completes this testing. In part, this risk is driven by the fact that the Navy is procuring
more than two-thirds of its 22 total radars prior to completing operational testing. Any
deficiencies the Navy discovers during at-sea testing could require revisions to existing
design drawings or retrofitting to already built radars, which would likely increase costs or
delay radar deliveries.
In order to support initial radar integration and testing with Aegis beginning in 2020, the
Navy plans to install production radar components at the Aegis combat system land -based
test site in New Jersey. Program officials said this is the first opportunity for AMDR and
Aegis contractors to integrate the systems to test interfaces and software compatibility. The
land-based tests will inform software development and integration of AMDR and Aegis in
support of ALO on the lead DDG 51 Flight III ship in 2022.
AMDR is well into low-rate initial production but has yet to demonstrate statistical control
of its critical manufacturing processes—an approach inconsistent with acquisition best
practices. In December 2019, the program exercised contract options that brought the
number of low-rate production units purchased to nine. However, the contractor continues
to experience cost and schedule growth on production radars due to issues with its Digital
Receiver Exciter (DREX)—a critical technology—and price variances on component
materials, which could affect the program’s procurement cost estimate if issues are not
resolved. Officials said a DREX subcomponent does not meet its vibration specifications,
despite a recent contractor redesign. The program is exploring multiple mitigation options.
The contractor reported that these issues have delayed delivery of the first radar to at least
August 2020, 4 months later than the contract’s delivery date. Program officials said they
could mitigate the issue by delivering the radar to the ship without the DREX unit and
installing the unit later with minimal impact to the schedule. However, delays have already
consumed schedule margin and may threaten the first DDG 51 Flight III installation in
2020 as well as AMDR/DDG 51 Flight III operational testing in 2023.
Software and Cybersecurity
AMDR has completed six of its nine software deliveries to support core radar capabilities,
but additional development remains to add capabilities, integrate cybersecurity measures,
and integrate AMDR with Aegis. Software is incrementally released every 4 months for
testing before the final build is delivered to the end user every 10-12 months. Program
officials said this aligns with Aegis software development, which is being developed
concurrently. AMDR and Aegis software development will continue through 2021 while
both systems integrate and test software.
The Navy has conducted some initial cybersecurity testing with AMDR but will not fully
test cybersecurity capabilities with Aegis until at least 2023. However, the program reports
some cost growth due to implementing cybersecurity controls. If cybersecurity issues arise
during testing, additional software development may cause further cost growth or disrupt
operational testing.
Other Program Issues
Congressional Research Service

10

link to page 15 Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress

The program is developing an Advanced Distributed Radar (ADR) capability that leverages
existing Navy technologies. The ADR capability increased the program’s cost estimate,
and the Navy projects it will require additional development funds through 2027. ADR is
expected to improve AMDR capability through radar enhancements. ADR will be
integrated on existing AMDR systems through software upgrades. The Navy plans to
finalize ADR requirements and begin development in 2020. Full ADR capability will not
be fielded until after the first AMDR-equipped DDG 51 Flight III is fielded in 2024.
Program Office Comments
We provided a draft of this assessment to the program office for review and comment. The
program office provided technical comments, which we incorporated where appropriate. It
stated that AMDR design is stable but software deficiencies might be discovered during
testing; AMDR’s demonstrated performance exceeded its performance thresholds during
land-based testing; and initial radar and Aegis integration began in 2016 and is on track to
support ALO and operational testing. The program office also said the contract type for the
low-rate initial production units minimizes the impact of component price variances and
some radar components have been delivered to support DDG 51 Flight III cons truction
schedules. According to the program office, initial cybersecurity updates are on track to
complete in 2021.15
Legislative Activity for FY2022
Summary of Congressional Action on FY2022 Funding Request
Table 1 summarizes congressional action on the Navy’s FY2022 procurement funding requests
for the DDG-51 and DDG-1000 programs.
Table 1. Congressional Action on FY2022 Funding Request
Mil ions of dol ars, rounded to nearest tenth
Authorization
Appropriation

Request
HASC
SASC
Conf.
HAC
SAC
Conf.
DDG-51 procurement
2,016.8

DDG-51 advance procurement (AP)
0.0

DDG-51 cost to complete
45.8

DDG-1000 procurement
56.6

Source: Table prepared by CRS based on Navy’s FY2022 budget submission, committee and conference
reports, and explanatory statements on FY2022 National Defense Authorization Act and FY2022 DOD
Appropriations Act.
Notes: HASC is House Armed Services Committee; SASC is Senate armed Services Committee; HAC is
House Appropriations Committee; SAC is Senate Appropriations Committee; Conf. is conference agreement.

15 Government Accountability Office, Weapon Systems Annual Assessment[:] Limited Use of Knowledge-Based
Practices Continues to Undercut DOD’s Investments, GAO-20-439, June 2020, p. 116.
Congressional Research Service

11

link to page 16

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

Appendix. Additional Background Information on
DDG-1000 Program
This appendix presents additional background information on the DDG-1000 program.
Overview
The DDG-1000 program was initiated in the early 1990s.16 DDG-1000s (Figure A-1) are multi-
mission destroyers with an original y 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 original y intended to replace, in a technological y more modern form, the
large-caliber naval gun fire capability that the Navy lost when it retired its Iowa-class battleships
in the early 1990s,17 to improve the Navy’s general capabilities for operating in defended littoral

16 T he program was originally designated DD-21, which meant destroyer for the 21st century. In November 2001, the
program was restructured and renamed DD(X), meaning a destroyer whose design was in development. In April 2006,
the program’s name was changed again, to DDG-1000, meaning a guided missile destroyer with the hull number 1000.
17 T he Navy in the 1980s reactivated and modernized four Iowa (BB-61) class battleships that were originally built
during World War II. T he ships reentered service between 1982 and 1988 and were removed from service between
1990 and 1992.
Congressional Research Service

12

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

waters, and to introduce several new technologies that would be available for use on future Navy
ships. The DDG-1000 was also intended to serve as the basis for a planned cruiser cal ed CG(X)
that was subsequently canceled.18
DDG-1000s are to have reduced-size crews of 175 sailors (147 to operate the ship, plus a 28-
person aviation detachment), compared to roughly 300 on the Navy’s Aegis destroyers and
cruisers, so as to reduce its operating and support (O&S) costs. The DDG-1000 design
incorporates a significant number of new technologies, including an integrated electric-drive
propulsion system19 and automation technologies enabling its reduced-sized crew.
With an estimated full load displacement of 15,656 tons, the DDG-1000 design is substantial y
larger than the Navy’s Aegis cruisers and destroyers, which have displacements of up to about
9,700 tons, and are larger than any Navy destroyer or cruiser since the nuclear-powered cruiser
Long Beach (CGN-9), which was procured in FY1957.
The first two DDG-1000s were procured in FY2007 and split-funded (i.e., funded with two-year
incremental funding) in FY2007-FY2008; the Navy’s FY2021 budget submission estimates their
combined procurement cost at $9,450.8 mil ion. The third DDG-1000 was procured in FY2009
and split-funded in FY2009-FY2010; the Navy’s FY2021 budget submission estimates its
procurement cost at $3,855.1 mil ion.
The first DDG-1000 was commissioned into service on September 7, 2016. Its delivery date was
revised multiple times. In the Navy’s FY2021 budget submission, the ship’s delivery date was
revised to March 2020. The ship’s actual delivery date reportedly was April 2020.20 This created
an unusual situation in which a ship was commissioned into service more than three years prior to
its delivery date. The delivery dates for the second and third ships have also been revised multiple
times.21 In the Navy’s FY2022 budget submission, the delivery dates for the two ships were
revised to March 2022 and April 2024, 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 cal ed 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:22

18 For more on the CG(X) program, see CRS Report RL34179, Navy CG(X) Cruiser Program: Background for
Congress, by Ronald O'Rourke.
19 For more on integrated electric-drive technology, see CRS Report RL30622, Electric-Drive Propulsion for U.S. Navy
Ships: Background and Issues for Congress, by Ronald O'Rourke.
20 See Aidan Quigley, “Final Delivery of Zumwalt-class Destroyer Monsoor Delayed,” Inside Defense, January 21,
2021.
21 T he 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. T he Navy’s original plan for the DDG-1000
program was to install certain elements of each DDG-1000’s combat system after delivering the ship and
commissioning it into service. Section 121 of P.L. 114-328 in effect requires the Navy to defer the delivery date of a
DDG-1000 until those elements of the combat system are installed. By the time P.L. 114-328 was enacted, DDG-1000,
per the Navy’s original plan, had already been commissioned into service without those elements of its combat system.
22 T he 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. T he SC-21 program envisaged a new destroyer called DD-21
Congressional Research Service

13

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

 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 bal istic missile mission; and
 a smaller combatant called the Littoral Combat Ship (LCS) to counter
submarines, smal surface attack craft (also cal ed “swarm boats”), and mines in
heavily contested littoral (near-shore) areas.23
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 stil cal ed the DD-21 program.24
New Technologies
The DDG-1000 incorporates a significant number of new technologies, including a wave-
piercing, tumblehome hull design for reduced detectability,25 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,26 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 cal ed the Advanced Gun System (AGS).
Shipbuilders and Combat System Prime Contractor
GD/BIW is the builder for al three DDG-1000s, with some portions of each ship being built by
HII/Ingal s 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/Ingal s, the second ship was to have been built by GD/BIW, and

and a new cruiser called CG-21. When the Navy announced the Future Surface Combatant Program in 2001,
development work on the DD-21 had been underway for several years, while the start of development work on the CG-
21 was still years in the future. T he current DDG-1000 destroyer CG(X) cruiser programs can be viewed as the
descendants, respectively, of the DD-21 and CG-21. T he 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).
23 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.
24 For more on Navy ship names, see CRS Report RS22478, Navy Ship Names: Background for Congress, by Ronald
O'Rourke.
25 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.
26 For more on integrated electric-drive technology, see CRS Report RL30622, Electric-Drive Propulsion for U.S. Navy
Ships: Background and Issues for Cong ress, by Ronald O'Rourke.
Congressional Research Service

14

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

contracts for building the first six were to have been equal y divided between HII/Ingal s27 and
GD/BIW.
In February 2005, Navy officials announced that they would seek approval from USD AT&L to
instead hold a one-time, winner-take-al competition between HII/Ingal s and GD/BIW to build
al 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-al 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-
al 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/Ingal s 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-al 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/Ingal s for
the construction of the two lead ships. The awards were modifications to existing contracts that
the Navy has with GD/BIW and HII/Ingal s 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/Ingal s 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/Ingal s.
On January 12, 2009, it was reported that the Navy, HII/Ingal s, and GD/BIW in the fal of 2008
began holding discussions on the idea of having GD/BIW build both the first and second DDG-
1000s, in exchange for HII/Ingal s 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.28
On April 8, 2009, it was reported that the Navy had reached an agreement with HII/Ingal s and
GD/BIW to shift the second DDG-1000 to GD/BIW, and to have GD/BIW build al three ships.

27 At the time of the events described in this section, HII was owned by Northrop Grumman and was called Northrop
Grumman Shipbuilding (NGSB).
28 Christopher P. Cavas, “Will Bath Build Second DDG 1000?” Defense News, January 12, 2009: 1, 6.
Congressional Research Service

15

link to page 21 Navy DDG-51 and DDG-1000 Destroyer Programs: Background and Issues for Congress

HII/Iingal s wil continue to make certain parts of the three ships, notably their composite
deckhouses. The agreement to have al three DDG-1000s built at GD/BIW was a condition that
Secretary of Defense Robert Gates set forth in an April 6, 2009, news conference on the FY2010
defense budget for his support for continuing with the construction of al three DDG-1000s
(rather than proposing the cancel ation of the second and third).
Reduction in Procurement to Three Ships
Navy plans for many years cal ed 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 final y 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 bal istic 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).29
Increase in Estimated Procurement Cost
As shown in Table A-1 below, the estimated combined procurement cost for al three DDG-
1000s, as reflected in the Navy’s annual budget submission, has grown by $4,328.8 mil ion, or
48.2%, since the FY2009 budget (i.e., the budget for the fiscal year in which the third DDG-1000
was procured).
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 al ocated to the fourth through seventh ships in the program to be real ocated to the
three remaining ships.

29 For additional discussion, see CRS Report R43838, Renewed Great Power Competition: Implications for Defense—
Issues for Congress, by Ronald O'Rourke, and CRS Report RL33153, China Naval Modernization: Im plications for
U.S. Navy Capabilities—Background and Issues for Congress, by Ronald O'Rourke.
Congressional Research Service

16

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

Table A-1. Estimated Combined Procurement Cost of DDG-1000, DDG-1001, and
DDG-2002
In mil ions, 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%)
Source: Table prepared by CRS based on data in annual Navy budget submissions.
The Navy states that the cost growth shown through FY2015 in the table reflects, among other
things, a series of incremental, year-by-year movements away from an earlier Navy cost estimate
for the program, and toward a higher estimate developed by the Cost Assessment and Program
Evaluation (CAPE) office within the Office of the Secretary of Defense (OSD). As one
consequence of a Nunn-McCurdy cost breach experienced by the DDG-1000 program in 2010
(see discussion below), the Navy was directed to fund the DDG-1000 program to CAPE’s higher
cost estimate for the period FY2011-FY2015, and to the Navy’s cost estimate for FY2016 and
beyond. The Navy states that it implemented this directive in a year-by-year fashion with each
budget submission from FY2010 through FY2015, moving incremental y 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 stil
about 3% below the program’s rebaselined starting point for calculating any new Nunn-McCurdy
cost breach on the program.30
Technical Risk and Test and Evaluation Issues
June 2020 GAO Report
A June 2020 GAO report assessing selected major DOD weapon acquisition programs stated the
following of the DDG-1000 program:

30 Source: Navy briefing for CRS and the Congressional Budget Office (CBO) on the DDG-1000 program, April 30,
2014.
Congressional Research Service

17

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

Technology Maturity, Design Stability, and Production Readiness
The DDG 1000 program has fully matured most, but not all, of its nine original current
critical technologies and reports a stable design. According to the Navy, the vertical launch
system, infrared signature, and total ship computing environment are each continuing to
approach maturity. The Navy expects to fully mature these systems as it completes ship
construction, certification, and testing over the next 2 years. In addition to these nine
technologies, the Navy has now added three critical technologies to meet its new mission:
a communication system, an intelligence system, and the seeker on an offensive strike
missile. These technologies are planned to be mature when they are integrated onto the
ship, but this integration will not occur until several years after the ship undergoes testing.
The Navy plans to complete operational testing of the lead ship in September 2021.
As of January 2020, the DDG 1000 program continues to finish construction on all three
ships while still maturing the remaining critical technologies and further defining the ship’s
new mission. The Navy planned to complete delivery of the DDG 1000 with its combat
systems in April 2020—a delay of 6 months from last year’s review. In total, the lead ship
is now 2 years late compared to the Navy’s original plans to complete this milestone.
The Navy plans to complete delivery of the DDG 1001 with its combat systems in
September 2020. Navy program officials stated that by leveraging lessons learned from
DDG 1000 combat system activation, they can complete DDG 1001 combat systems
delivery in less than 3 years. Lastly, the Navy plans to deliver DDG 1002 with its combat
systems in September 2022—a 9-month delay from last year’s estimate.
Software and Cybersecurity
As we reported last year, the Navy plans to complete software development for the class
in September 2020—a delay of 24 months since our 2018 assessment largely due to
optimistic schedules for development. As a result, the Navy has had to delay some testing
that the ship must complete before it is ready to deploy. In addition, although the lead ship
was delivered in 2016, the program is still continuing to deliver software builds that achieve
some of the promised automation. Since the software is not as capable and does not enable
as much automation as originally planned, among other things, the Navy has permanently
added 31 sailors to the crew compared to initial estimates, increasing life-cycle costs.
The program plans to complete a cybersecurity vulnerability evaluation in fiscal year 2021
connected with section 1647 of the National Defense Authorization Act for Fiscal Year
2016. The program expects that this evaluation, along with the remainder of a 2-year
regimen of certifications and several different tests in September 2020, will demonstrate
the full functionality of the ship’s systems, including cybersecurity capability. According
to program officials, no cybersecurity issues have been identified to date.
Other Program Issues
In January 2018, the Navy changed the ship class’s primary mission from land attack to
offensive surface strike and updated its requirements document to reflect this new mission
in July 2018. To begin to enable the new surface strike mission over the next 5 or more
years, the Navy is requesting $160 million for four new systems for the ships: two missile
systems, a communications system, and an intelligence system. One missile system is
planned to be installed on all three ships by September 2021 at a cost of $66 million. The
second missile system is not planned to be installed on any of the ships for at least 5 years
and needs significant development at a cost of $45 million —additional funds will be
needed to purchase and install the system. The communications system will be installed on
all three ships by fiscal 2023 and costs $22 million. Lastly, the intelligence system is not
planned to be installed on any of the ships for at least 5 years and needs significant
development at a cost of $40 million—additional funds will be needed to purchase and
install the system.
Congressional Research Service

18

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

The cost to develop and install these four systems is in addition to the program’s
procurement cost as it is accounted for in other procurement and research and development
funding. According to Navy officials, the Navy may continue to add capability to support
the new mission.
Program Office Comments
We provided a draft of this assessment for program office review and comment. The
program office provided technical comments, which we incorporated where appropriate.
The office stated that it is making good progress in delivering DDG 1000 class ships to the
fleet. After our date for assessing new information from programs, the office stated that in
March 2020 the DDG 1000 had achieved sufficient combat system installation and
activation for the Navy to take delivery and transition to the next phase of developmental
and integrated at-sea testing. Further, the office said that in 2019, the DDG 1000 spent
more than 100 days at sea to maintain crew proficiency, support fleet operations, conduct
testing and provide an early opportunity for the ship to engage in operational scenarios. It
also said the DDG 1001 completed its combat availability in March 2020 with a successful
sea trial and is transitioning to combat systems activation. The office also said the final
ship of the class, DDG 1002, is under construction and 93 percent complete, and that
integration of the new systems will add offensive capability against targets afloat and
ashore across the DDG 1000 class.31
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 bil ion, 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 wil provide acceptable capability to
meet the joint military requirement at less cost.32
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.33 Since

31 Government Accountability Office, Defense Acquisitions Annual Assessment[:] Drive to Deliver Capabilities Faster
Increases Im portance of Program Knowledge and Consistent Data for Oversight, GAO-20-439, June 2020, p. 122.
32 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.
33 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.
Congressional Research Service

19

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

the DDG-1000 program has roughly $9.3 bil ion in research and development costs, truncating
the program to three ships increased to roughly $3.1 bil ion the average amount of research and
development costs that are included in the average acquisition cost (i.e., average research and
development cost plus procurement cost) of each DDG-1000. The resulting increase in program
acquisition unit cost (PAUC)—one of two measures used under the Nunn-McCurdy provision for
measuring cost growth34—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.35 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 original y
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 overal 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

34 PAUC is the sum of the program’s research and development cost and procurement cost divided by the number of
units in the program. T he 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.
35 Letter dated June 1, 2010, from Ashton Carter, Under Secretary of Defense (Acquisition, T echnology and Logistics)
to the Honorable Ike Skelton, with attachment. The letter and attachment were posted on InsideDefense.com
(subscription required) on June 2, 2010.
Congressional Research Service

20

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

software modification to provide the volume search capability will be significantly less
than the estimated procurement costs for the VSR.36
Regarding the figure of $300 mil ion 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 mil ion
the cost to integrate the dual-band radar into the Navy’s new Gerald R. Ford (CVN-78) class
aircraft carriers.37 Subtracting this $54 mil ion cost from the above $300 mil ion savings figure
would bring the net total cost savings to about $246 mil ion 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.”38
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 al 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 wil 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] shortfal [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 bil ion per ship in then-year dollars
($22.1 bil ion in then-year dollars for al 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 bil ion per ship in then-year dollars ($12.8 bil ion in then-year dollars for al
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 wil
exceed these cost estimates.
An attachment to the letter directed the Navy to “return for a Defense Acquisition Board (DAB)
review in the fal 2010 timeframe when the program is ready to seek approval of the new

36 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.
37 Source: Undated Navy information paper on CVN-78 cost issues, provided by Navy Office of Legislative Affairs to
CRS on March 19, 2012.
38 Cid Standifer, “Volume Radar Contracted For DDG-1000 Could Be Shifted T o CVN-79,” Inside the Navy, July 26,
2010. See also Joseph T revithick and T yler Rogoway, “ Navy's T roubled Stealth Destroyers May Have Radars
Replaced Before Ever Sailing On A Mission,” The Drive, October 15, 2020.
Congressional Research Service

21

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

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-1000.39

Author Information

Ronald O'Rourke

Specialist in Naval Affairs

Disclaimer
This document was prepared by the Congressional Research Service (CRS). CRS serves as nonpartisan
shared staff to congressional committees and Members of Congress. It operates solely at the behest of and
under the direction of Congress. Information in a CRS Report should n ot be relied upon for purposes other
than public understanding of information that has been provided by CRS to Members of Congress in
connection with CRS’s institutional role. CRS Reports, as a work of the United States Government, are not
subject to copyright protection in the United States. Any CRS Report may be reproduced and distributed in
its entirety without permission from CRS. However, as a CRS Report may include copyrighted images or
material from a third party, you may need to obtain the permission of the copyright holder if you wish to
copy or otherwise use copyrighted material.

39 Christopher J. Castelli, “Pentagon Approves Key Milestone For Multibillion-Dollar Destroyer,” Inside the Navy,
November 22, 2010.
Congressional Research Service
RL32109 · VERSION 241 · UPDATED
22