Navy TAGOS(X) Ocean Surveillance Shipbuilding Program: Background and Issues for Congress [Updated October 19, 2021] [open pdf - 800KB]
From the Document: "The Navy wants to procure in FY2022 the first of a planned new class of seven TAGOS(X) ocean surveillance ships. The Navy's proposed FY2022 budget requests $434.4 million for the procurement of the first TAGOS(X). [...] TAGOS ships support Navy antisubmarine warfare (ASW) operations. As stated in the Navy's FY2021 budget submission, TAGOS ships 'use the Surveillance Towed-Array Sensor System (SURTASS [Surveillance Towed-Array Sensor System]) to gather undersea acoustic data. They also carry electronic equipment to process and transmit that data via satellite to shore stations for evaluation.'"
CRS In Focus, IF11838
Congressional Research Service: https://crsreports.congress.gov/