Explorer-class surveillance ship

The Explorer-class ocean surveillance ship is a planned class of United States Navy special mission-support ship. Also known as the T-AGOS 25 program, the ships are planned to replace five other ocean surveillance ships and is speculated to be in response to modernized submarines from Russia and China.^[2] The ships will be SWATH catamarans, and carry SURTASS towed array sonar for anti-submarine warfare,^[1] as well as collecting acoustic data for the IUSS submarine detection system.^[2]

Class overview
Name	Explorer class
Builders	Austal USA, Mobile, Alabama
Operators	United States Navy
Preceded by	Impeccable class
Cost	US$789.6 million for first ship (FY2025) US$3.2 billion for 7 ships (FY2023)[1]
Planned	7
Building	0
Completed	0
Cancelled	0
Active	0
General characteristics
Displacement	8,500 tons
Length	356 ft (109 m)
Crew	68
Sensors & processing systems	SURTASS passive and active low frequency sonar arrays

History

On 18 May 2023, the Navy awarded US$3.2 billion to the Austal USA shipyard in Mobile, Alabama to construct seven Explorer-class vessels. On May 30, 2024, the Navy awarded an additional $516 million to account for cost growth on the procurement of the first ship.^[1] On 10 January 2025, Secretary of the Navy Carlos Del Toro named the first two ships the USNS Don Walsh (T-AGOS 25) and the USNS Victor Vescovo (T-AGOS 26) after undersea explorers Don Walsh and Victor Vescovo, both of whom dove to the deepest known point on Earth's seabed, Challenger Deep.^[3]

Similar ship classes

The Explorer class is similar in construction to the earlier Victorious and the Impeccable-class ocean surveillance ships, with all three classes of ship using SWATH type hulls. The Explorer class is designed to replace both classes of ship.^[4]