The second USS ''Mercer'' (APB 39/IX 502/APL 39) is an

Benewah-class barracks ship The ''Benewah''-class barracks ship was a class of barracks ships of the United States Navy after the Second World War, in the late 1940s. Development Thirteen ships were converted into repair ships throughout the later stages of World War II ...

of the

United States Navy The United States Navy (USN) is the naval warfare, maritime military branch, service branch of the United States Department of Defense. It is the world's most powerful navy with the largest Displacement (ship), displacement, at 4.5 millio ...

. Originally classified as Barracks Craft APL 39, the ship was reclassified as Self-Propelled Barracks Ship APB 39 on 7 August 1944. Laid down on 24 August 1944 by

Boston Navy Yard The Boston Navy Yard, originally called the Charlestown Navy Yard and later Boston Naval Shipyard, was one of the oldest shipbuilding facilities in the United States Navy. It was established in 1801 as part of the recent establishment of t ...

, and launched on 17 November 1944 as ''APB 39'', sponsored by Mrs. Lillian Gaudette, the ship was named ''Mercer'', after counties in eight states, on 14 March 1945, and commissioned on 19 September 1945.

Service history

New York, 1945–1947

''Mercer'', a barracks ship built on an LST hull, commenced her career of berthing and messing large numbers of naval personnel at New York on 7 November 1945. Transferred to the Inactive Fleet in January 1946, for their first few days after they arrived in New York in March 1946 she served as quarters for the newly assigned 79 member Marine security detachment for the United Nations Organization meetings at Hunter College in The Bronx, she remained at New York until 9 September, when she got underway for

Orange, Texas Orange is a city in and the county seat of Orange County, Texas, United States. The population was 19,324 at the 2020 census. It is the easternmost city in Texas, located on the Sabine River at the border with Louisiana, and is from Houston. ...

, and remained in duty there until the spring of 1947. She then headed for

Green Cove Springs, Florida Green Cove Springs is a city in and the county seat of Clay County, Florida, United States. Green Cove Springs is a part of the Jacksonville, Florida Metropolitan Statistical Area. The population was 9,786 at the 2020 census, up from 6,908 at ...

, where she was decommissioned on 18 June 1947, but remained in service with the Florida Group, Atlantic Reserve Fleet.

Naples, Rhode Island and Argentina, 1951–1956

She was recommissioned on 12 October 1951 and after a brief overhaul sailed for

Norfolk, Virginia Norfolk ( ) is an independent city (United States), independent city in the U.S. state of Virginia. It had a population of 238,005 at the 2020 United States census, 2020 census, making it the List of cities in Virginia, third-most populous city ...

, en route to

Naples, Italy Naples ( ; ; ) is the Regions of Italy, regional capital of Campania and the third-largest city of Italy, after Rome and Milan, with a population of 908,082 within the city's administrative limits as of 2025, while its Metropolitan City of N ...

, where she served as a

receiving ship A hulk is a ship that is afloat, but incapable of going to sea. 'Hulk' may be used to describe a ship that has been launched but not completed, an abandoned wreck or shell, or a ship whose propulsion system is no longer maintained or has been r ...

until 1 July 1952. Returning to the United States on 21 July, she underwent an overhaul and reported to

Davisville, Rhode Island Davisville is a village in the town of North Kingstown and county of Washington County in the U.S. state of Rhode Island. It was formerly the home of the Davisville Naval Construction Battalion Center, which housed the United States Navy's Sea ...

, for duty as a barracks ship for Mobile

Construction Battalion United States Naval Construction Battalions, better known as the Navy Seabees, form the U.S. Naval Construction Forces (NCF). The Seabee nickname is a heterograph of the initial letters "CB" from the words "Construction Battalion". Dependi ...

s. On such duty into late 1955, ''Mercer'' was thrice deployed to

Argentia, Newfoundland Argentia ( ) is a Canadian commercial seaport and industrial park located in the Town of Placentia, Newfoundland and Labrador. It is situated on the southwest coast of the Avalon Peninsula and defined by a triangular shaped headland which re ...

from 19 March to 3 October 1953, 14 March to 18 October 1954, and 27 February to 25 July 1955. Her Seabee duty was interrupted when she sailed to

Washington, D.C. Washington, D.C., formally the District of Columbia and commonly known as Washington or D.C., is the capital city and federal district of the United States. The city is on the Potomac River, across from Virginia, and shares land borders with ...

, to berth midshipmen of the

United States Merchant Marine Academy The United States Merchant Marine Academy (USMMA or Kings Point) is a United States service academies, United States service academy in Kings Point, New York. It trains its midshipman, midshipmen (as students at the academy are called) to serv ...

taking part in President

Dwight D. Eisenhower Dwight David "Ike" Eisenhower (born David Dwight Eisenhower; October 14, 1890 – March 28, 1969) was the 34th president of the United States, serving from 1953 to 1961. During World War II, he was Supreme Commander of the Allied Expeditionar ...

's 1953 Inaugural Parade. Upon returning from her 1955 Argentina deployment, ''Mercer'' sailed to New York for a pre-inactivation overhaul, and on 7 November she sailed for Green Cove Springs where she was decommissioned 17 February 1956, and once again entered the Reserve Fleet. Eleven years later she was reactivated and taken to

Long Beach, California Long Beach is a coastal city in southeastern Los Angeles County, California, United States. It is the list of United States cities by population, 44th-most populous city in the United States, with a population of 451,307 as of 2022. A charter ci ...

for modernization.

Vietnam, 1968–1969

She was recommissioned on 11 May 1968 and on 2 June reported for duty with the Amphibious Force, Pacific Fleet, at San Diego. Within the month she was en route to her ultimate assignment,

South Vietnam South Vietnam, officially the Republic of Vietnam (RVN; , VNCH), was a country in Southeast Asia that existed from 1955 to 1975. It first garnered Diplomatic recognition, international recognition in 1949 as the State of Vietnam within the ...

where she arrived at Vung Tau on 31 July. Well into 1969 she supported

Mobile Riverine Force In the Vietnam War, the Mobile Riverine Force (MRF) (after May 1967), initially designated Mekong Delta Mobile Afloat Force, and later the Riverines, were a joint US Army and US Navy force that comprised a substantial part of the brown-water n ...

fighting

Viet Cong The Viet Cong (VC) was an epithet and umbrella term to refer to the communist-driven armed movement and united front organization in South Vietnam. It was formally organized as and led by the National Liberation Front of South Vietnam, and ...

and

People's Army of Vietnam The People's Army of Vietnam (PAVN), officially the Vietnam People's Army (VPA; , , ), also recognized as the Vietnamese Army (), the People's Army () or colloquially the Troops ( ), is the national Military, military force of the Vietnam, S ...

forces operating in South Vietnam. ''Mercer'' left Vietnam in August 1969 and then served as a Barricks Ship at Willamette Iron and Steel Works in Portland, OR. in the mid 1970s.

Sasebo, 1975–1980s

Decommissioned and reclassified as Miscellaneous Auxiliary IX 502, a messing and berthing barge, she was placed in service on 1 November 1975 at the US Naval Ship Repair Facility,

Sasebo, Japan is a core city located in Nagasaki Prefecture, Japan. It is the second-largest city in Nagasaki Prefecture, after its capital, Nagasaki. , the city had an estimated population of 230,873 in 102,670 households, and a population density of 540 per ...

1980s and 1990s

IX 502 served during the 1980s as a berthing barge at Naval Station San Diego, providing sleeping quarters, messing, and classroom accommodation for crews of ships undergoing maintenance. The ship was towed in the early 1990s to the Long Beach Naval Shipyard, California, where she served the same function until the shipyard closed in 1997.

Return to Sasebo

Reclassified as Barracks Ship (non-self propelled) ''APL 39'' on 7 March 2001, ''APL 39'' is part of the CincPacFlt Berthing and Messing Program and is berthed at SRF Det. Sasebo, Japan. It was listed for auction on 2 December 2024https://www.gsaauctions.gov/auctions/preview/307208

Awards

USS ''Mercer'' earned four

campaign star A service star is a miniature bronze or silver five-pointed star in diameter that is authorized to be worn by members of the eight uniformed services of the United States on medals and ribbons to denote an additional award or service period. T ...

s for Vietnam War service with four awards of the

Combat Action Ribbon The Combat Action Ribbon (CAR) is a United States Navy, United States Coast Guard, and United States Marine Corps military decoration awarded to United States sea service members "who have actively participated in ground or surface combat." Coast ...

, in addition to the Presidential Unit Citation and the

Navy Unit Commendation The Navy Unit Commendation (NUC) is a United States Navy and United States Coast Guard unit award that was established by order of the Secretary of the Navy James Forrestal on 18 December 1944. History Navy A navy, naval force, military m ...

References

History of the USS ''Mercer'' (APB 39)
* * {{DEFAULTSORT:Mercer (APL 39) Benewah-class barracks ships Mercer County, Illinois Mercer County, Kentucky Mercer County, Missouri Mercer County, New Jersey Mercer County, North Dakota Mercer County, Ohio Mercer County, Pennsylvania Mercer County, West Virginia Ships built in Boston 1945 ships Vietnam War auxiliary ships of the United States Atlantic Reserve Fleet, Green Cove Springs Group