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Updated June 1, 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
TAGOS(X) program for FY2022-FY2025 in the Navy’s
shipbuilding account (the Shipbuilding and Conversion,
Quantity, Schedule, and Design
Navy, or SCN, appropriation account) in annual amounts of
The Navy wants to build seven TAGOS(X) ships as
$437.1 million, $427.9 million, $418.7 million, and $399.4
replacements for its five in-service TAGOS ships. The
million.
Navy’s FY2021 budget submission called for procuring the
first four TAGOS(X)s at a rate of one per year in FY2022-
Research and Development Funding
FY2025. The Navy’s notional design for the TAGOS(X)
Research and development work on the TAGOS(X)
(Figure 4) employs a SWATH design that would be larger
program is funded through the Navy’s research and
and faster than the in-service TAGOS ships. Table 1
development account in Project 3261 (TAGOS Design and
compares the TAGOS-19 and TAGOS-23 designs to the
Total Ship Integration) within Program Element (PE)
Navy’s notional TAGOS(X) design.
0204313N (Ship-Towed Array Surveillance Systems). PE
0204313N is line 211 in the Navy’s FY2022 research and
Figure 4. Notional Navy Design for TAGOS(X)
development account.
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
attended. In January 2020, the Navy released a request for
Source: Artist’s rendering accompanying press released entitled
proposals (RFP) for contracts to perform initial industry
“Halter Marine Secures Contract for Industrial Studies for T-AGOS
studies for the program. On July 2, 2020, the Navy awarded
Program,” Halter Marine, July 20, 2020.
four contracts for these studies to BMT Designers and
Planners of Arlington, VA (with a contract value $2.37
Table 1. TAGOS Ship Designs
million); Bollinger Shipyards of Lockport, LA ($2.78
million); Thoma-Sea Marine Constructors of Houma, LA
TAGOS-
TAGOS-
TAGOS(X)
($2.26 million); and VT Halter Marine of Pascagoula, MS
19
23
(notional)
($2.17 million). The Navy will use the industry studies to
inform its understanding of TAGOS(X) design-cost
Length
235 feet
281 feet
356 feet
tradeoffs in support of the RFP that the Navy will release
Maximum speed
10 knots
12 knots
20 knots
for the DD&C contract.
Ful load
3,384 tons
5,330 tons
8,500 tons
Issues for Congress
displacement
Potential issues for Congress for the TAGOS(X) program
Accommodations
~48
54
68
include the following:
Sources: “Ocean Surveil ance Ships - T-AGOS,” U.S. Navy, and
whether the Navy has accurately identified the required
“Ocean Surveil ance Ships,” Military Sealift Command, accessed May
number and capabilities (and resulting size and cost) of
26, 2021, and briefing slide entitled “T-AGOS Class Comparison,”
TAGOS(X) ships needed to perform future missions;
slide 22 from Industry Day briefing for TAGOS(X) program, June 26,
2019, accessed May 26, 2021, at GovTribe.com.
whether the Navy’s estimated procurement cost for
TAGOS(X)s is accurate; and
The Navy’s desire to replace the five in-service TAGOS
the impact of the TAGOS(X) program on the U.S.
ships with seven larger and faster TAGOS(X)s can be
shipbuilding industrial base, including both shipyards
viewed as a response by the Navy to the submarine
and supplier firms.
modernization efforts of countries such as China and
Russia. For more on China’s submarine modernization
FY2022 Procurement Funding
effort, see CRS Report RL33153, China Naval
The Navy’s proposed FY2022 budget requests $434.4
Modernization: Implications for U.S. Navy Capabilities—
million for the procurement of the first TAGOS(X).
Back ground and Issues for Congress, by Ronald O'Rourke.
Procurement Cost
Ronald O'Rourke, Specialist in Naval Affairs
The Navy estimates that TAGOS(X) ships will cost about
IF11838
$400 million each to procure. The Navy’s FY2021 budget
submission projected procurement funding for the
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Navy TAGOS(X) Ocean Surveil ance Shipbuilding Program: Background and Issues for Congress
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