TS State of Maine is the training ship of the Maine Maritime Academy. Originally commissioned by the United States Navy as USNS Tanner (T-AGS-40), the ship assumed her present name and role in June 1997.

Several ships have borne the name State of Maine since the Maine Maritime Academy was founded in 1941. Previous vessels included the former USS Comfort (AH-6), which served in the role from 1953 to 1963; USS Ancon (AGC-4); and USNS Upshur (T-AP-198).

USNS Tanner (T-AGS-40), was built for the United States Navy as a fast oceanographic research vessel by Bethlehem Steel Corporation at its Sparrows Point Yard in Maryland in 1990. The vessel was the second oceanographic research ship to bear the name of Zera Luther Tanner, a noted oceanographer and inventor of a patented sounding machine. The vessel experienced catastrophic engine failure in 1993 and was laid up by the Navy and eventually transferred ownership to the Maritime Administration (MARAD).

The ship lay idle in the James River Reserve Fleet until 1996 when she began a conversion process, which removed her underwater sonar domes and equipment. The two original engines were removed and a new power plant was installed. The newer engine is significantly less powerful than the old engines. The sister ship, Maury (T-AGS-39), now the third vessel of the name TS Golden Bear, retained the original and more powerful enterprise engines.

The vessel was modified to increase the accommodations from 108 to 302 persons. New lifesaving equipment and upgrades to existing equipment were accomplished as well as enhancements to the habitability requirements of the vessel. She was delivered to Maine Maritime Academy on 6 June 1997 and sailed her maiden training cruise the following week.

State of Maine was called into active duty by the Maritime Administration (MARAD) following Hurricane Katrina and provided living quarters for oil rig workers, who were working to repair damaged rigs, and for Federal Law Enforcement Officers assisting in New Orleans.

The ship is normally docked at her pier in Castine when not on a training cruise or in drydock. State of Maine is classed with the American Bureau of Shipping, and all inspections of her hull and equipment are undertaken by this classification society. The ship entered drydock for scheduled maintenance and inspections following the summer cruise of 2007. She also entered drydock following the Summer Cruise of 2012, keeping within the inspection schedule required by US Coast Guard Regulations. Most recently, she entered drydock at the conclusion of her 2017 summer cruise. She was observed in the dry dock at South Boston MA undergoing repairs during the first week of July 2022 before she returned to service in November of 2022.

She made her final voyage in summer 2024.

As a National Security Multi-Mission Vessel, the State of Maine will be replaced by the State of Maine V which has completed initial construction and is scheduled to be delivered to begin service at the Academy in 2025.

State of Maine's sister ship is TS Golden Bear, the training ship of the California Maritime Academy. Golden Bear was formerly USNS Maury.

• "State of Maine History". Maine Maritime Academy. Retrieved 2013-07-22.
• Photo gallery of USS Tanner at NavSource Naval History
•  This article includes information collected from the Naval Vessel Register, which, as a U.S. government publication, is in the public domain. The entry can be found here.

• U.S. Maritime Administration

44°23.17′N 68°47.79′W / 44.38617°N 68.79650°W / 44.38617; -68.79650