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Updated July 29, 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’s proposed FY2022 budget requests $434.4
The five in-service TAGOS ships are Small Waterplane
million for the procurement of the first TAGOS(X). The
Area Twin Hull (SWATH) ships. In a SWATH ship, the
issue for Congress is whether to approve, reject, or modify
upper part of the ship sits on top of two struts that extend
the Navy’s funding requests and acquisition strategy for the
down to a pair of submerged hulls that look like submarine
program.
hulls (Figure 2). The struts have a narrow cross section at
the waterline (i.e., they have a small waterplane area). The
TAGOS Ships in the Navy
SWATH design has certain limitations, but has features
TAGOS ships (Figure 1 and Figure 2) support Navy
(including very good stability in high seas) that are useful
antisubmarine warfare (ASW) operations. As stated in the
for SURTASS operations.
Navy’s FY2021 budget submission, TAGOS ships “use the
Surveillance Towed-Array Sensor System (SURTASS) to
Figure 2. USNS Effective (TAGOS-21) in Dry Dock
gather undersea acoustic data. They also carry electronic
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 Surveil ance
Ships,” Military Sealift Command, accessed May 25, 2021.
Current TAGOS Ships
Source: Detail from briefing slide entitled “TAGOS(X) Concept of
The Navy currently operates five aging TAGOS ships—
Operations (CONOPS),” slide 13 in Industry Day briefing for
four Victorious (TAGOS-19) class ships (TAGOS 19
TAGOS(X) program, June 26, 2019, accessed May 26, 2021, at
through 22) that entered service between 1991 and 1993,
GovTribe.com.
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
Navy, or SCN, appropriation account) in annual amounts of
$437.1 million, $427.9 million, $418.7 million, and $399.4
Quantity, Schedule, and Design
million.
The Navy wants to build seven TAGOS(X) ships as
replacements for its five in-service TAGOS ships. The
Research and Development Funding
Navy’s FY2021 budget submission called for procuring the
Research and development work on the TAGOS(X)
first four TAGOS(X)s at a rate of one per year in FY2022-
program is funded through the Navy’s research and
FY2025. The Navy’s notional design for the TAGOS(X)
development account in Project 3261 (TAGOS Design and
(Figure 4) employs a SWATH design that would be larger
Total Ship Integration) within Program Element (PE)
and faster than the in-service TAGOS ships. Table 1
0204313N (Ship-Towed Array Surveillance Systems). PE
compares the TAGOS-19 and TAGOS-23 designs to the
0204313N is line 211 in the Navy’s FY2022 research and
Navy’s notional TAGOS(X) design.
development account.
Figure 4. Notional Navy Design for TAGOS(X)
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.
In January 2020, the Navy released a request for proposals
(RFP) for contracts to perform initial industry studies for
the program. On July 2, 2020, the Navy awarded four
contracts for these studies to BMT Designers and Planners
of Arlington, VA (with a contract value $2.37 million);
Bollinger Shipyards of Lockport, LA ($2.78 million);
Source: Artist’s rendering accompanying press released entitled
Thoma-Sea Marine Constructors of Houma, LA ($2.26
“Halter Marine Secures Contract for Industrial Studies for T-AGOS
million); and VT Halter Marine of Pascagoula, MS ($2.17
Program,” Halter Marine, July 20, 2020.
million). The Navy will use the industry studies to inform
its understanding of TAGOS(X) design-cost tradeoffs in
Table 1. TAGOS Ship Designs
support of the RFP that the Navy will release for the DD&C
contract.
TAGOS-
TAGOS-
TAGOS(X)
19
23
(notional)
Issues for Congress
Potential issues for Congress for the TAGOS(X) program
Length
235 feet
281 feet
356 feet
include the following:
Maximum speed
10 knots
12 knots
20 knots
whether the Navy has accurately identified the required
Ful load
3,384 tons
5,330 tons
8,500 tons
number and capabilities (and resulting size and cost) of
displacement
TAGOS(X) ships needed to perform future missions;
Accommodations
~48
54
68
whether the Navy’s estimated procurement cost for
Sources: “Ocean Surveil ance Ships - T-AGOS,” U.S. Navy, and
TAGOS(X)s is accurate; and
“Ocean Surveil ance Ships,” Military Sealift Command, accessed May
the impact of the TAGOS(X) program on U.S. shipyards
26, 2021, and briefing slide entitled “T-AGOS Class Comparison,”
and associated supplier firms.
slide 22 from Industry Day briefing for TAGOS(X) program, June 26,
2019, accessed May 26, 2021, at GovTribe.com.
FY2022 Procurement Funding
The Navy’s proposed FY2022 budget requests $434.4
The Navy’s desire to replace the five in-service TAGOS
million for the procurement of the first TAGOS(X).
ships with seven larger and faster TAGOS(X)s can be
viewed as a response by the Navy to the submarine
The House Appropriations Committee’s report (H.Rept.
modernization efforts of countries such as China and
117-88 of July 15, 2021) on the FY2022 DOD
Russia. For more on China’s submarine modernization
Appropriations Act (H.R. 4432) recommends approving the
effort, see CRS Report RL33153, China Naval
Navy’s FY2022 procurement funding request for the
Modernization: Implications for U.S. Navy Capabilities—
TAGOS(X) program. Section 8104 of H.R. 4432 as
Background and Issues for Congress, by Ronald O'Rourke.
reported by the committee establishes U.S. content
requirements for three shipbuilding programs, including the
Procurement Cost
TAGOS(X) program.
The Navy estimates that TAGOS(X) ships will cost about
$400 million each to procure. The Navy’s FY2021 budget
submission projected procurement funding for the
Ronald O'Rourke, Specialist in Naval Affairs
TAGOS(X) program for FY2022-FY2025 in the Navy’s
IF11838
shipbuilding account (the Shipbuilding and Conversion,
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Navy TAGOS(X) Ocean Surveillance Shipbuilding Program: Background and Issues for Congress
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