USNS Vindicator (T-AGOS-3) was a United States Navy Stalwart-class modified tactical auxiliary general ocean surveillance ship that was in service from 1984 to 1993.

The Navy placed the ship in non-commissioned service in the Military Sealift Command on the day of her delivery as USNS Vindicator (T-AGOS-3).

Designed to collect underwater acoustical data in support of Cold War anti-submarine warfare operations using Surveillance Towed Array Sensor System (SURTASS) sonar equipment, Vindicator spent the final years of the Cold War searching for Soviet Navy submarines.

On 30 June 1993, the Navy removed Vindicator from service and simultaneously struck her from the Naval Vessel Register and leased her to the United States Coast Guard.

During 1994, manned by many former crew members of the by-then-decommissioned Tamaroa, Vindicator took part in Operation Able Manner, a joint U.S. Coast Guard-U.S. Navy effort to interdict would-be Haitian migrants to the United States.

[8] Budget cuts in early 2001 resulted in termination of the lease, and she was decommissioned again on 1 May 2001 and returned to the Military Sealift Command.

After a $4,000,000 conversion into an oceanographic research ship, she was commissioned into NOAA service on 3 September 2004 as NOAAS Hiʻialakai (R 334), co-sponsored by Margaret "Maggie" Awamura Inouye, the wife of United States Senator from Hawaiʻi Daniel Inouye, and University of Hawaiʻi Professor Emerita Isabella A.

[13] Hiʻialakai made her longest cruise — a 103-day voyage — during a 2015 assessment of coral reefs in the National Marine Sanctuary of American Samoa.