Dutch ocean going minesweeper Hr. Ms. Onverschrokken (1952-1970) and torpedo work ship Mercuur (A856) 1970-1987

Lying as museum ship at Scheveningen, Netherlands on 27 July 2007

Call signs in American service first Am483 and later MSO 583. Laid down at the shipyard of the Peterson Builders Incorporation, Sturgeon Bay, Wisconsin, USA on 19 February 1952, launched on 17 January 1953 and commissioned on 22 July 1953 as Hr. Ms. Onverschrokken (M886). She and her sister ships were built in the USA and handed over to the Netherlands according to the Mutual Defense Assistance Program. Since 1 January 1969 classified as headquarters-support ship for minesweepers squadrons.

Displacement 790 tons and as dimensions 55,00 x 10,70 x 3,70 metres. Original diesel motors supplying 1.600 hp allowing via 2 screws a speed of 15,5 knots. Her crew numbered 67 men. The armament consisted of 1-4cm machinegun.

Since 1970 was she no longer used as a minesweeper and was in 1972 she rebuilt as a torpedo work ship and at the same time renamed Mercuur. She assisted at torpedo launching tests executed by submarine by afterwards picking up the torpedo and taken at board preparing for the next test launching. Further more served she as target during torpedo tests. In 1987 was she stricken when the new Mercuur (A900) built by Damen Schelde Naval Shipbuilding her replaced. She was temporarily handed over by the Stichting Nautisch Kwartier Amsterdam, however given back to the Royal Netherlands Navy after some time. She was then handed over to the Stichting Behoud Maritieme Monumenten and was lying since 1992 at Scheveningen, Netherlands until December 2015 when she was towed back to Den Helder, Netherlands after she was given back to the Royal Netherlands Navy on 15 December. At the moment it’s not know what her fate will be.