HMS Girdle Ness was a Beachy Head-class repair ship constructed for the Royal Navy that entered service in 1945.

After trials of the missile were completed, Girdle Ness was placed in reserve before becoming an accommodation ship as part of the shore establishment HMS Cochrane at Rosyth.

Following setbacks in the Pacific theatre of operations which led to the loss of naval bases, the Royal Navy required more depot and repair ships for the fleet to replace shore facilities.

[1] As part of the war construction programme, the Royal Navy ordered a series of vessels based on standard mercantile designs and modified them to fit their expected roles.

[7] She was built by the Burrard Dry Dock Co. Ltd. at their yard in Vancouver, British Columbia, Canada, as one of twenty-one Beachy Head-class repair ships.

During her conversion the entire superstructure was removed and most of the forward part of the hull gutted to provide space for the missile launcher and its attendant magazines.

One of the reasons why Girdle Ness was chosen for conversion was a result of a 1950 Admiralty Ship Design Policy Committee recommendation.

The following equipment was installed:[10][page needed] Seaslug was first tested at RAE Aberporth, on the Welsh coast of Cardigan Bay.

The ship's badge, a golden girdle as a trefoil knot on a blue field, is now held by the National Maritime Museum, Greenwich.