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May 27, 2021
Navy TAGOS(X) Ocean Surveillance Shipbuilding Program:
Background and Issues for Congress
Introduction
service in 2000. As of the end of FY2020, all five were
The Navy wants to procure in FY2022 the first of a planned
homeported at Yokohama, Japan.
new class of seven TAGOS(X) ocean surveillance ships.
The Navy estimates that TAGOS(X) ships will cost about
The five in-service TAGOS ships are Small Waterplane
$400 million each. The issue for Congress is whether to
Area Twin Hull (SWATH) ships. In a SWATH ship, the
approve, reject, or modify the Navy’s funding requests and
upper part of the ship sits on top of two struts that extend
acquisition strategy for the program.
down to a pair of submerged hulls that look like submarine
hulls (Figure 2). The struts have a narrow cross section at
TAGOS Ships in the Navy
the waterline (i.e., they have a small waterplane area). The
TAGOS ships (Figure 1 and Figure 2) support Navy
SWATH design has certain limitations, but has features
antisubmarine warfare (ASW) operations. As stated in the
(including very good stability in high seas) that are useful
Navy’s FY2021 budget submission, TAGOS ships “use the
for SURTASS operations.
Surveillance Towed-Array Sensor System (SURTASS) to
gather undersea acoustic data. They also carry electronic
Figure 2. USNS Effective (TAGOS-21) in Dry Dock
equipment to process and transmit that data via satellite to
shore stations for evaluation.” Figure 3 shows a simplified
diagram of a TAGOS(X) ship with its SURTASS arrays
trailing below and behind the ship.
In the designation TAGOS (also written as T-AGOS), the T
means they are operated by the Military Sealift Command
(MSC); the A means they are auxiliary (i.e., support) ships;
the G means they have a general or miscellaneous mission;
and the OS means the mission is ocean surveillance. In the
program designation TAGOS(X), the X means that the new
TAGOS ship’s precise design has not yet been determined.
Figure 1. USNS Impeccable (TAGOS-23)
Source: U.S. Navy photograph 070913-N-2638R-004 posted at
Wikimedia Commons, accessed May 25, 2021.
Figure 3. TAGOS(X) Ship with SURTASS Arrays
Source: U.S. Navy photograph accompanying “Ocean Surveillance
Ships,” Military Sealift Command, accessed May 25, 2021.
Source: Detail from briefing slide entitled “TAGOS(X) Concept of
Current TAGOS Ships
Operations (CONOPS),” slide 13 in Industry Day briefing for
The Navy currently operates five aging TAGOS ships—
TAGOS(X) program, June 26, 2019, accessed May 26, 2021, at
four Victorious (TAGOS-19) class ships (TAGOS 19
GovTribe.com.
through 22) that entered service between 1991 and 1993,
and one Impeccable (TAGOS-23) class ship that entered
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Navy TAGOS(X) Ocean Surveillance Shipbuilding Program: Background and Issues for Congress
TAGOS(X) Program
in the Navy’s shipbuilding account (the Shipbuilding and
Conversion, Navy, or SCN, appropriation account) in
Quantity, Schedule, and Design
annual amounts of $437.1 million, $427.9 million, $418.7
The Navy wants to build seven TAGOS(X) ships as
million, and $399.4 million.
replacements for its five in-service TAGOS ships. The
Navy’s FY2021 budget submission calls for procuring the
Research and Development Funding
first four TAGOS(X)s at a rate of one per year in FY2022-
Research and development work on the TAGOS(X)
FY2025. The Navy’s notional design for the TAGOS(X)
program is funded through the Navy’s research and
(Figure 4) employs a SWATH design that would be larger
development account in Project 3261 (TAGOS Design and
and faster than the in-service TAGOS ships. Table 1
Total Ship Integration) within Program Element (PE)
compares the TAGOS-19 and TAGOS-23 designs to the
0204313N (Ship-Towed Array Surveillance Systems). PE
Navy’s notional TAGOS(X) design.
0204313N is line 213 in the Navy’s FY2021 research and
development account. For FY2021, the Navy requested
Figure 4. Notional Design for TAGOS(X)
$10.9 million for Project 3261. As part of its action on the
Navy’s FY2021 budget, Congress approved this request.
Acquisition Strategy
The Navy wants to use a single shipbuilder to build all
seven TAGOS(X)s. The Navy intends to competitively
award in FY2022 a firm fixed-price contract for the detailed
design and construction (DD&C) of the lead ship, with
options for building up to six additional ships.
On June 26 and 27, 2019, the Navy held an industry day for
the TAGOS(X) program to brief the program to interested
firms. Representatives from 11 shipyards and 27 other firms
Source: Artist’s rendering accompanying press released entitled
attended. In January 2020, the Navy released a request for
“Halter Marine Secures Contract for Industrial Studies for T-AGOS
proposals (RFP) for contracts to perform initial industry
Program,” Halter Marine, July 20, 2020.
studies for the program. On July 2, 2020, the Navy awarded
four contracts for these studies to BMT Designers and
Table 1. TAGOS Ship Designs
Planners of Arlington, VA (with a contract value $2.37
million); Bollinger Shipyards of Lockport, LA ($2.78
TAGOS-
TAGOS-
TAGOS(X)
million); Thoma-Sea Marine Constructors of Houma, LA
19
23
(notional)
($2.26 million); and VT Halter Marine of Pascagoula, MS
($2.17 million). The Navy will use the industry studies to
Length
235 feet
281 feet
356 feet
inform its understanding of TAGOS(X) design-cost
Maximum speed
10 knots
12 knots
20 knots
tradeoffs in support of the RFP that the Navy will release
for the DD&C contract.
Full load
3,384 tons
5,330 tons
8,500 tons
displacement
Issues for Congress
Accommodations
~48
54
68
Potential issues for Congress for the TAGOS(X) program
include the following:
Sources: “Ocean Surveillance Ships - T-AGOS,” U.S. Navy, and
“Ocean Surveillance Ships,” Military Sealift Command, accessed May
whether the Navy has accurately identified the required
26, 2021, and briefing slide entitled “T-AGOS Class Comparison,”
number and capabilities (and resulting size and cost) of
slide 22 from Industry Day briefing for TAGOS(X) program, June 26,
TAGOS(X) ships needed to perform future missions;
2019, accessed May 26, 2021, at GovTribe.com.
whether the Navy’s estimated procurement cost for
The Navy’s desire to replace the five in-service TAGOS
TAGOS(X)s is accurate; and
ships with seven larger and faster TAGOS(X)s can be
the impact of the TAGOS(X) program on the U.S.
viewed as a response by the Navy to the submarine
shipbuilding industrial base, including both shipyards
modernization efforts of countries such as China and
and supplier firms.
Russia. For more on China’s submarine modernization
effort, see CRS Report RL33153, China Naval
FY2022 Procurement Funding
Modernization: Implications for U.S. Navy Capabilities—
The Navy’s proposed FY2022 budget is scheduled to be
Background and Issues for Congress, by Ronald O'Rourke.
submitted to Congress on May 28, 2020.
Procurement Cost
As mentioned earlier, the Navy estimates that TAGOS(X)
Ronald O'Rourke, Specialist in Naval Affairs
ships will cost about $400 million each to procure. The
IF11838
Navy’s FY2021 budget submission projects procurement
funding for the TAGOS(X) program for FY2022-FY2025
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Navy TAGOS(X) Ocean Surveillance Shipbuilding Program: Background and Issues for Congress
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