The Achelous class repair ship was a class of ship built by the US Navy during World War II

World War II

World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

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As the US gained experience in amphibious operations

Amphibious warfare

Amphibious warfare is the use of naval firepower, logistics and strategy to project military power ashore. In previous eras it stood as the primary method of delivering troops to non-contiguous enemy-held terrain...

, it was realized that some sort of mobile repair facility would be useful for repairing the damage that frequently occurred to smaller vessels such as LCVP

LCVP

The Landing Craft, Vehicle, Personnel or Higgins boat was a landing craft used extensively in amphibious landings in World War II. The craft was designed by Andrew Higgins of Louisiana, United States, based on boats made for operating in swamps and marshes...

's (Landing Craft Vehicle/Personnel). The Auxiliary Repair Light (ARL) ship was designed to meet this need, and the Achelous class was the only class to receive this designation.

Description

Achelous class vessels were based on the same hull

Hull (watercraft)

A hull is the watertight body of a ship or boat. Above the hull is the superstructure and/or deckhouse, where present. The line where the hull meets the water surface is called the waterline.The structure of the hull varies depending on the vessel type...

 as LST's (Landing Ship, Tank) which at the time were being produced in large numbers. This hull was thought to be ideal for a ship specializing in the repair of light craft, since it was not overly large and had a shallow draught

Draft (hull)

The draft of a ship's hull is the vertical distance between the waterline and the bottom of the hull , with the thickness of the hull included; in the case of not being included the draft outline would be obtained...

 which would enable it to maneuver into small harbors, rivers and inlets where it could service damaged boats and effect other repairs on location.

The conversion from an LST to an Achelous class ARL was done mainly by converting the large interior tank

Tank

A tank is a tracked, armoured fighting vehicle designed for front-line combat which combines operational mobility, tactical offensive, and defensive capabilities...

 deck into a number of different shops and storerooms. Two large cargo booms were added forward, and a large 60-ton A-frame boom added amidships. The wheelhouse/chart room deck was expanded, and a conning tower added. The first nine units of the class sealed the bow doors of the LST hull.

The ship's company consisted of the usual LST crew of deck, engineering and communications departments but in addition it had a supply department, plus a repair department consisting of machinery and engine repair, carpentry, electronics repair, and hull repair divisions, giving a ship's complement of approximately 250 officers and men in total. After the first nine units were built, the later units had a revised armament as well as retaining the opening bow doors.

Operational history

During World War II, the Achelous class vessels worked mostly on repairing damaged landing craft, but many continued in service after the war, working again on landing craft during the Korean War

Korean War

The Korean War was a conventional war between South Korea, supported by the United Nations, and North Korea, supported by the People's Republic of China , with military material aid from the Soviet Union...

 and on river craft during the Vietnam War

Vietnam War

The Vietnam War was a Cold War-era military conflict that occurred in Vietnam, Laos, and Cambodia from 1 November 1955 to the fall of Saigon on 30 April 1975. This war followed the First Indochina War and was fought between North Vietnam, supported by its communist allies, and the government of...

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In all, 39 Achelous class repair ships were built between 1943 and 1945.