HNLMS ''Onverschrokken'' (A856), also known as HNLMS ''Mercuur'' (A856), was an of the Royal Netherlands Navy (RNN). Soon after being taken into service of the RNN, the ship was put into reserve alongside the rest of the minesweepers of the ''Onversaagd'' class.Roetering (1997), p. 131. Later, in 1973 she was renamed as HNLMS ''Mercuur'' (A856) and used as submarine support ship till her decommissioning in 1987. Nowadays, she is a

museum ship A museum ship, also called a memorial ship, is a ship that has been preserved and converted into a museum open to the public for educational or memorial purposes. Some are also used for training and recruitment purposes, mostly for the small num ...

that can be visited in

Vlissingen Vlissingen (; zea, label= Zeelandic, Vlissienge), historically known in English as Flushing, is a municipality and a city in the southwestern Netherlands on the former island of Walcheren. With its strategic location between the Scheldt river ...

History

The former submarine support ship ex HNLMS ''Mercuur'' was originally built as HNLMS ''Onverschrokken'', as part of the ''Aggressive''-class wooden ocean minesweepers with the

yard number __NOTOC__ M ...

MSO 483. These minesweepers were built in the early 1950s in the

United States The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 U.S. state, states, a Washington, D.C., federal district, five ma ...

and were equipped with an AN/SQQ-14 minehunting

sonar Sonar (sound navigation and ranging or sonic navigation and ranging) is a technique that uses sound propagation (usually underwater, as in submarine navigation) to navigate, measure distances ( ranging), communicate with or detect objects on ...

to locate moored or bottom

naval mine A naval mine is a self-contained explosive device placed in water to damage or destroy surface ships or submarines. Unlike depth charges, mines are deposited and left to wait until they are triggered by the approach of, or contact with, any ve ...

s. To do this it had electromagnetic cables to set off mines and other cables to cut through their mooring lines, while they were also equipped with devices which could produce magnetic and acoustical charge to let mines explode. The ''Aggressive'' class was a large ship class with more than 80 ships. The reason for this many minesweepers was that the United States was in need of minesweepers for clearing mines that were laid during the

Korean War {{Infobox military conflict , conflict = Korean War , partof = the Cold War and the Korean conflict , image = Korean War Montage 2.png , image_size = 300px , caption = Clockwise from top: ...

by various countries. Most of the minesweepers served for many years in

United States Navy The United States Navy (USN) is the maritime service branch of the United States Armed Forces and one of the eight uniformed services of the United States. It is the largest and most powerful navy in the world, with the estimated tonnage ...

and other allied navies. One of these allied navies that employed ''Aggressive'' class in their navy was the Royal Netherlands Navy (RNN). The

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

was loaned six ''Aggressive''-class minesweepers as part the United States' financial and material aid under the

Mutual Defense Assistance Program The Mutual Defense Assistance Act was a United States Act of Congress signed by President Harry S. Truman on 6 October 1949. For US Foreign policy, it was the first U.S. military foreign aid legislation of the Cold War era, and initially to Euro ...

, among these minesweepers was HNLMS ''Onverschrokken''. The ship arrived in the Netherlands on 22 July 1954 and was given the pendant M886. The ships of the ''Onverschokken'' class, including ''Onverschokken'' itself, visited many harbors in Netherlands to search and clear sea mines that were left over after the

Second World War World War II or the Second World War, often abbreviated as WWII or WW2, was a world war that lasted from 1939 to 1945. It involved the World War II by country, vast majority of the world's countries—including all of the great power ...

. Besides these important tasks she could also be seen frequently as part of the Dutch navy delegation that took part in multinational (NATO and bi- or tri-national)

exercises Exercise is a body activity that enhances or maintains physical fitness and overall health and wellness. It is performed for various reasons, to aid growth and improve strength, develop muscles and the cardiovascular system, hone athletic sk ...

off the European coast during the Cold War. In 1965 her role changed from minesweeper to escort ship and at the same time her registration changed from M886 to A856. ''Mercuur'', which was in service for decades, was barely able to perform her tasks at the beginning of the 1970s due her age and therefore the RNN came to the decision to turn the ''Onverschrokken'' into a torpedo support ship. In this role she would support submarines by performing torpedo tests and act as target ship. After her re-design ''Onverschrokken'' was renamed ''Mercuur'' like her predecessor. ''Mercuur'' was decommissioned in 1987 after her

successor Successor may refer to: * An entity that comes after another (see Succession (disambiguation)) Film and TV * ''The Successor'' (film), a 1996 film including Laura Girling * ''The Successor'' (TV program), a 2007 Israeli television program Mus ...

, which was also named ''Mercuur'', was completed. After her decommissioning the ship was loaned in 1988 to the Nautisch Kwartier Amsterdam Foundation. However, this was for a short duration since the foundation could not build a use-case for and she was therefore returned. In 1992 the Foundation for the Conservation of Maritime Monuments (SBMM) agreed to loan the ''Mercuur'' docked the ship for decades in the harbor of

Scheveningen Scheveningen is one of the eight districts of The Hague, Netherlands, as well as a subdistrict (''wijk'') of that city. Scheveningen is a modern seaside resort with a long, sandy beach, an esplanade, a pier, and a lighthouse. The beach is ...

, where she was turned into a museumship and frequently visited by people all around. a new loan and a mooring place was found in Scheveningen. In February 2015, the Dutch Ministry of Defense commissioned all museum ships to be investigated for the presence of asbestos. When traces were found on board of ''Mercuur'', the Dutch Ministry of Defense ordered the ship to be closed in anticipation of further decision-making. The Ministry of Defense also decided that it no longer wanted to be the owner and decided that the ship would either be donated to the SBMM, demolished or remediation would take place. Upon acquisition in ownership, a new phase would start for the exploitation of the Mercuur. A number of volunteers decided, partly in view of their age, to stop their efforts and not to start a new phase again. This deprived the SBMM of the possibility of continuing the exploitation with the prospect of success. Based on this, in consultation between the SBMM and the Ministry of Defense, ''Mercuur'' was brought to

Den Helder Den Helder () is a municipality and a city in the Netherlands, in the province of North Holland. Den Helder occupies the northernmost point of the North Holland peninsula. It is home to the country's main naval base. From here the Royal TESO ...

in December 2015 with the intention to start the tender for remediation and demolition. In early 2016, contacts were made between the SBMM and the Maritime Heritage Vlissingen Foundation (SMEV) to see whether the ship could serve as a

after the asbestos removal. In 2016 the Stichting Maritiem Erfgoed Vlissingen prevented the destruction of the ''Mercuur'' when it made a deal with the RNN to get time to develop a business-plan for her as museum ship. After the plan was accepted she was towed to Vlissingen, the RNN helped there with removing the asbestos from the ship and converting her into a museum ship. This conversion was completed in 2017 after which she was towed once again to a different location, this time the dry dock named Dok van Perry where she would spend all her future time from now. The Defense Materiel Organization (DMO) officially transferred HNLMS ''Mercuur'' on 1 September 2017 to the Stichting Maritiem Erfgoed Vlissingen (SMEV) which will take care of her as museum ship.

Citations

References

* * {{DEFAULTSORT:Onverschrokken Onversaagd-class minesweepers 1953 ships Ships built by Peterson Builders Museum ships in the Netherlands