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Updated August 30, 2022
Navy TAGOS-25 (Previously TAGOS[X]) Ocean Surveillance
Shipbuilding Program: Background and Issues for Congress
Introduction
22) that entered service in 1991-1993, and one Impeccable
The first of a planned class of seven new TAGOS-25 class
(TAGOS-23) class ship that entered service in 2000. As of
ocean surveillance ships was procured in FY2022 at a cost
the end of FY2021, all five were homeported at Yokohama,
of $434.4 million. The Navy wants to procure the second
Japan. The ships use a Small Waterplane Area Twin Hull
ship in FY2025. The Navy’s proposed FY2023 budget
(SWATH) design, in which the ship’s upper part sits on two
requests no FY2023 procurement funding for the program.
struts that extend down to a pair of submerged, submarine-
like hulls (Figure 2). The struts have a narrow cross section
Meaning of TAGOS Designation
at the waterline (i.e., they have a small waterplane area).
In the designation TAGOS (also written as T-AGOS), the T
The SWATH design has certain limitations, but it has
means the ships are operated by the Military Sealift
features (including very good stability in high seas) that are
Command (MSC); the A means they are auxiliary (i.e.,
useful for SURTASS operations.
support) ships; the G means they have a general or
miscellaneous mission; and the OS means the mission is
Figure 2. USNS Effective (TAGOS-21) in Dry Dock
ocean surveillance. The TAGOS-25 program was
previously known as the TAGOS(X) program, with the (X)
meaning that the precise design for the ship had not yet
been determined. Some Navy budget documents may
continue to refer to the program that way.
TAGOS Ships in the Navy
TAGOS ships (Figure 1 and Figure 2) support Navy
antisubmarine warfare (ASW) operations. As stated in the
Navy’s FY2023 budget submission, TAGOS ships “use
Surveillance Towed-Array Sensor System (SURTASS)
equipment to gather undersea acoustic data. The ships 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-25 ship with its
SURTASS arrays.
Source: U.S. Navy photograph 070913-N-2638R-004 posted at
Figure 1. USNS Impeccable (TAGOS-23)
Wikimedia Commons, accessed May 25, 2021.
Figure 3. TAGOS Ship with SURTASS Arrays
Source: U.S. Navy photograph accompanying “Ocean Surveil ance
Source: Detail from slide 13, entitled “TAGOS(X) Concept of
Ships,” Military Sealift Command, accessed May 25, 2021.
Operations (CONOPS),” in Industry Day briefing for TAGOS(X)
program, June 26, 2019, accessed May 26, 2021, at GovTribe.com.
Current TAGOS Ships
The Navy’s five aging TAGOS ships include four
Victorious (TAGOS-19) class ships (TAGOS 19 through
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Navy TAGOS-25 (Previously TAGOS[X]) Ocean Surveillance Shipbuilding Program: Background and Issues for Congress
TAGOS-25 Program
design and construction (DD&C) of the lead ship, with
options for building up to six additional ships.
Quantity, Schedule, and Design
The Navy wants to procure seven TAGOS-25 class ships as
In January 2020, the Navy released a request for proposals
replacements for its five in-service TAGOS ships. The first
(RFP) for contracts to perform initial industry studies for
TAGOS-25 class ship was procured in FY2022. The
the program. On July 2, 2020, the Navy awarded four
Navy’s FY2023 budget submission calls for procuring the
contracts for these studies to BMT Designers and Planners
second in FY2025, the third and fourth in FY2026, and the
of Arlington, VA (with a contract value $2.37 million);
fifth in FY2027. The Navy’s notional design for the
Bollinger Shipyards of Lockport, LA ($2.78 million);
TAGOS-25 class (Figure 4) employs a SWATH design that
Thoma-Sea Marine Constructors of Houma, LA ($2.26
would be larger and faster than the in-service TAGOS ships
million); and VT Halter Marine of Pascagoula, MS ($2.17
(see Table 1).
million).
Figure 4. Notional Navy Design for TAGOS-25
The Navy used the industry studies to inform its
understanding of TAGOS-25 design-cost tradeoffs in
support of the RFP for the DD&C contract. The Navy
posted the RFP for the DD&C contract on November 19,
2021, and amended it on December 21, 2021. Responses to
the RFP were due by April 19, 2022.
Issues for Congress
Potential issues for Congress for the TAGOS-25 program
include the following:
whether the Navy has accurately identified the required
number and capabilities (and resulting size and cost) of
Source: Artist’s rendering accompanying press released entitled
TAGOS-25s needed to perform future missions;
“Halter Marine Secures Contract for Industrial Studies for T-AGOS
whether the Navy’s estimated procurement cost for
Program,” Halter Marine, July 20, 2020.
TAGOS-25s is accurate;
Table 1. TAGOS Ship Designs
whether to accelerate the procurement of the second
ship in the program from FY2025 to FY2024 or
TAGOS-
TAGOS-
TAGOS-25
FY2023; and
19
23
(notional)
the impact of the TAGOS-25 program on U.S. shipyards
Length
235 feet
282 feet
356 feet
and associated supplier firms.
Maximum speed
10 knots
13 knots
20 knots
FY2023 Procurement Funding
Displacement
3,384 tons
5,370 tons
8,500 tons
The Navy’s proposed FY2023 budget requests no FY2023
procurement funding for the TAGOS-25 program, which is
Accommodations
~48
54
68
line 23 in the Navy’s FY2023 Shipbuilding and
Sources: “Ocean Surveil ance Ships - T-AGOS,” U.S. Navy, and (for
Conversion, Navy (SCN) appropriation account. The House
TAGOS-25) slide 22, entitled “T-AGOS Class Comparison,” from
Armed Services Committee’s report (H.Rept. 117-397 of
Industry Day briefing for TAGOS(X) program, June 26, 2019,
July 1, 2022, page 432) on the FY2023 National Defense
accessed May 26, 2021, at GovTribe.com.
Authorization Act (NDAA) (H.R. 7900), the Senate Armed
Services Committee’s report (S.Rept. 117-130 of July 18,
The Navy’s desire to replace the five in-service TAGOS
2022, page 407) on the FY2023 NDAA (S. 4543), the
ships with seven larger and faster TAGOS-25s can be
House Appropriations Committee’s report (H.Rept. 117-
viewed as a response by the Navy to the submarine
388 of June 24, 2022, page 140) on the FY2023 DOD
modernization efforts of countries such as China and
Appropriations Act (H.R. 8236), and the Senate
Russia. For more on China’s submarine modernization
Appropriations Committee’s explanatory statement for the
effort, see CRS Report RL33153, China Naval
FY2023 DOD Appropriations Act (S. 4663), released on
Modernization: Implications for U.S. Navy Capabilities—
July 28, 2022 (page 112), all recommend no FY2023
Background and Issues for Congress, by Ronald O'Rourke.
procurement funding for the TAGOS-25 program.
Procurement Cost
Section 8100 of H.R. 8236 and Section 8101 of S. 4663
The Navy estimates in its FY2023 budget submission that
would require that all auxiliary equipment for TAGOS-25
the seven TAGOS-25s will cost an average of $426.3
ships, including pumps and propulsion shafts, be
million each in then-year dollars to procure.
manufactured in the United States.
Acquisition Strategy
Ronald O'Rourke, Specialist in Naval Affairs
The Navy wants to use a single shipbuilder to build all
seven TAGOS-25s. The Navy intends to competitively
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award in FY2022 a firm fixed-price contract for the detailed
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Navy TAGOS-25 (Previously TAGOS[X]) Ocean Surveillance Shipbuilding Program: Background and Issues for Congress
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