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Updated September 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 Surveil ance Shipbuilding Program: Background and Issues for Congress
TAGOS(X) Program
$437.1 million, $427.9 million, $418.7 million, and $399.4
million.
Quantity, Schedule, and Design
The Navy wants to build seven TAGOS(X) ships as
Research and Development Funding
replacements for its five in-service TAGOS ships. The
Research and development work on the TAGOS(X)
Navy’s FY2021 budget submission called for procuring the
program is funded through the Navy’s research and
first four TAGOS(X)s at a rate of one per year in FY2022-
development account in Project 3261 (TAGOS Design and
FY2025. The Navy’s notional design for the TAGOS(X)
Total Ship Integration) within Program Element (PE)
(Figure 4) employs a SWATH design that would be larger
0204313N (Ship-Towed Array Surveillance Systems). PE
and faster than the in-service TAGOS ships. Table 1
0204313N is line 211 in the Navy’s FY2022 research and
compares the TAGOS-19 and TAGOS-23 designs to the
development account.
Navy’s notional TAGOS(X) design.
Acquisition Strategy
Figure 4. Notional Navy Design for TAGOS(X)
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);
Thoma-Sea Marine Constructors of Houma, LA ($2.26
Source: Artist’s rendering accompanying press released entitled
million); and VT Halter Marine of Pascagoula, MS ($2.17
“Halter Marine Secures Contract for Industrial Studies for T-AGOS
million). The Navy will use the industry studies to inform
Program,” Halter Marine, July 20, 2020.
its understanding of TAGOS(X) design-cost tradeoffs in
support of the RFP that the Navy will release for the DD&C
Table 1. TAGOS Ship Designs
contract.
TAGOS-
TAGOS-
TAGOS(X)
Issues for Congress
19
23
(notional)
Potential issues for Congress for the TAGOS(X) program
include the following:
Length
235 feet
281 feet
356 feet
Maximum speed
10 knots
12 knots
20 knots
whether the Navy has accurately identified the required
number and capabilities (and resulting size and cost) of
Ful load
3,384 tons
5,330 tons
8,500 tons
TAGOS(X) ships needed to perform future missions;
displacement
whether the Navy’s estimated procurement cost for
Accommodations
~48
54
68
TAGOS(X)s is accurate; and
Sources: “Ocean Surveil ance Ships - T-AGOS,” U.S. Navy, and
the impact of the TAGOS(X) program on U.S. shipyards
“Ocean Surveil ance Ships,” Military Sealift Command, accessed May
and associated supplier firms.
26, 2021, and briefing slide entitled “T-AGOS Class Comparison,”
slide 22 from Industry Day briefing for TAGOS(X) program, June 26,
FY2022 Procurement Funding
2019, accessed May 26, 2021, at GovTribe.com.
The Navy’s proposed FY2022 budget requests $434.4
million for the procurement of the first TAGOS(X). The
The Navy’s desire to replace the five in-service TAGOS
House and Senate Armed Services Committees’ reports
ships with seven larger and faster TAGOS(X)s can be
(H.Rept. 117-118 of September 10, 2021 and S.Rept. 117-
viewed as a response by the Navy to the submarine
39 of September 22 [legislative day, September 21], 2021,
modernization efforts of countries such as China and
respectively) on the FY2022 National Defense
Russia. For more on China’s submarine modernization
Authorization Act (H.R. 4350/S. 2792) and the House
effort, see CRS Report RL33153, China Naval
Appropriations Committee’s report (H.Rept. 117-88 of July
Modernization: Implications for U.S. Navy Capabilities—
15, 2021) on the FY2022 DOD Appropriations Act (H.R.
Back ground and Issues for Congress, by Ronald O'Rourke.
4432) recommend approving this request. Section 8104 of
Procurement Cost
H.R. 4432 as reported by the House Appropriations
Committee establishes U.S. content requirements for three
The Navy estimates that TAGOS(X) ships will cost about
shipbuilding programs, including the TAGOS(X) program.
$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
shipbuilding account (the Shipbuilding and Conversion,
IF11838
Navy, or SCN, appropriation account) in annual amounts of
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Navy TAGOS(X) Ocean Surveil ance Shipbuilding Program: Background and Issues for Congress
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