HMS Hermes was a Centaur-class

Centaur class aircraft carrier

The Centaur class of aircraft carriers of the British Royal Navy was the last of the light fleet carrier designs started during the closing years of World War II.-Ships In Class:HMS Centaur...

 British aircraft carrier

Aircraft carrier

An aircraft carrier is a warship designed with a primary mission of deploying and recovering aircraft, acting as a seagoing airbase. Aircraft carriers thus allow a naval force to project air power worldwide without having to depend on local bases for staging aircraft operations...

, the last of the postwar conventional aircraft carrier

Aircraft carrier

An aircraft carrier is a warship designed with a primary mission of deploying and recovering aircraft, acting as a seagoing airbase. Aircraft carriers thus allow a naval force to project air power worldwide without having to depend on local bases for staging aircraft operations...

s commissioned into the Royal Navy

Royal Navy

The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

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She was laid down by Vickers-Armstrong at Barrow-in-Furness

Barrow-in-Furness

Barrow-in-Furness is an industrial town and seaport which forms about half the territory of the wider Borough of Barrow-in-Furness in the county of Cumbria, England. It lies north of Liverpool, northwest of Manchester and southwest from the county town of Carlisle...

 during WW 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...

 as HMS Elephant. Construction was suspended in 1945 but work was resumed in 1952 to clear the slipway

Slipway

A slipway, boat slip or just a slip, is a ramp on the shore by which ships or boats can be moved to and from the water. They are used for building and repairing ships and boats. They are also used for launching and retrieving small boats on trailers and flying boats on their undercarriage. The...

 and the hull was launched on 16 February 1953. The vessel remained unfinished until 1957, when she entered service on 18 November 1959 as HMS Hermes after extensive modifications which included installation of a massive Type 984 'searchlight' 3D radar

3D radar

3D radar provides for radar coverage on three dimensions unlike the more common 2D radar. While the normal 2D radar provides range and azimuth, the 3D radar provides elevation information with range and azimuth...

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Hermes cost £18 million, with another £1 million for electronic equipment and £10 million for aircraft in 1959.
A 1966 review indicating that Hermes was surplus to operational requirements and was offered to the Royal Australian Navy

Royal Australian Navy

The Royal Australian Navy is the naval branch of the Australian Defence Force. Following the Federation of Australia in 1901, the ships and resources of the separate colonial navies were integrated into a national force: the Commonwealth Naval Forces...

 as a replacement for HMAS Melbourne.