https://crsreports.congress.gov
Updated December 21, 2022
Navy Next-Generation Attack Submarine (SSN[X]) Program:
Background and Issues for Congress
Introduction
The Navy wants to begin procuring a new class of nuclear-
powered attack submarine (SSN), called the Next-
Generation Attack Submarine or SSN(X), in the mid-2030s.
The SSN(X) would be the successor to the Virginia-class
SSN design, which the Navy has been procuring since
FY1998. The Navy’s proposed FY2023 budget requests
$237.0 million in research and development funding for the
SSN(X) program.
Submarines in the U.S. Navy
The U.S. Navy operates nuclear-powered ballistic missile
submarines (SSBNs), nuclear-powered cruise missile and
special operations forces (SOF) submarines (SSGNs), and
nuclear-powered attack submarines (SSNs). The SSNs are
general-purpose submarines that can perform a variety of
peacetime and wartime missions.
Virginia-Class Program
As mentioned above, the Navy has been procuring
Virginia-class SSNs (Figure 1) since FY1998. Since
FY2011, the Navy has been procuring them at a rate of two
boats per year. When procured at a rate of two boats per
year, Virginia-class SSNs equipped with the Virginia
Payload Module (VPM) have a current estimated
procurement cost of about $3.6 billion per boat. (Most
Virginia-class boats procured in FY2019 and subsequent
years are to be built with the VPM, an additional mid-body
section equipped with four large-diameter, vertical launch
tubes.) For additional information on Navy submarine
programs, see CRS Report RL32418, Navy Virginia (SSN-
774) Class Attack Submarine Procurement: Background
and Issues for Congress, by Ronald O'Rourke, and CRS
Report R41129, Navy Columbia (SSBN-826) Class Ballistic
Missile Submarine Program: Background and Issues for
Congress, by Ronald O'Rourke.
Submarine Construction Industrial Base
U.S. Navy submarines are built by General Dynamics’
Electric Boat Division (GD/EB) of Groton, CT, and
Quonset Point, RI, and Huntington Ingalls Industries’
Newport News Shipbuilding (HII/NNS), of Newport News,
VA. These are the only two shipyards in the country
capable of building nuclear-powered ships. GD/EB builds
submarines only, while HII/NNS also builds nuclear-
powered aircraft carriers. The submarine construction
industrial base also includes hundreds of supplier firms, as
well as laboratories and research facilities, in numerous
states. Much of the material procured from supplier firms
for building submarines comes from sole-source suppliers.
SSN(X) Program
Program Designation
In the designation SSN(X), the “X” means that the exact
design of the boat has not yet been determined.
Procurement Schedule
The Navy wants to shift from procuring Virginia-class
boats to procuring SSN(X)s in the mid-2030s.
Figure 1. Virginia-Class Attack Submarine (SSN)
Source: Cropped version of photograph accompanying Dan Ward,
“Opinion: How Budget Pressure Prompted the Success of Virginia-
Class Submarine Program,” USNI News, November 3, 2014. The
caption states that it shows USS Minnesota (SSN-783) under
construction in 2012, and credits the photograph to the U.S. Navy.
Design of the SSN(X)
The Navy states that the SSN(X)
will be designed to counter the growing threat posed
by near peer adversary competition for undersea
supremacy. It will provide greater speed, increased
horizontal payload capacity, improved acoustic
superiority, and higher operational availability.
SSN(X) will conduct full spectrum undersea
warfare and be able to coordinate with a larger
contingent of off-hull vehicles, sensors, and
friendly forces. It will retain and improve multi-
mission... capability and sustained combat presence
in denied waters.
(Budget-justification book for FY2023 Research,
Development, Test, and Evaluation, Navy account,
Vol. 3 [Budget Activity 5], p. 1305.)
Navy officials have stated that the Navy wants the SSN(X)
to be an “apex predator.” More specifically, they have
stated that the Navy wants the SSN(X) to incorporate the
speed and payload the Navy’s fast and heavily armed
Seawolf (SSN-21) class SSN design, the acoustic quietness
