MV ''Rocknes'' was a -long rock discharge vessel that hit shallow water and suddenly capsized south of

Bergen Bergen (, ) is a city and municipalities of Norway, municipality in Vestland county on the Western Norway, west coast of Norway. Bergen is the list of towns and cities in Norway, second-largest city in Norway after the capital Oslo. By May 20 ...

, Norway on 19 January 2004, killing 18 members of its 30-person crew. At the time of its sinking, it was the world's largest dynamically positioned flexible fall pipe rock dumping vessel.M.V. Rocknes
. Retrieved on 2008-08-07. The ship was repaired during 2004 and 2005 and renamed ''Nordnes''. ''Rocknes'' was owned by Kvitnes Shipping Company Ltd. of St. Johns, a part of the Hartmann group of Cadenberge, Germany. The ship was on a long-term charter to

Van Oord ACZ Royal Van Oord is a Dutch maritime contracting company that specializes in dredging, land reclamation and constructing man made islands. Royal Van Oord has undertaken many projects throughout the world, including land reclamation, dredging and bea ...

, an international contractor specializing in dredging, rock dumping, and offshore and coastal construction.

Conversion

Conversion of the ship was commissioned on 3 May 2003 in response to the increasing demand for offshore rock dumping. The ship was converted from the self unloading bulk carrier MV ''Kvitnes'' at Keppel Verolme Shipyard,

Botlek image.html" ;"title="image.html" ;"title="Satellite image">Satellite image of the Rhine–Meuse–Scheldt delta">Rhine–Meuse delta showing the Botlek (r). Botlek is an industrial port area of Rotterdam, the Netherlands. It specialises in pet ...

, The

Netherlands , Terminology of the Low Countries, informally Holland, is a country in Northwestern Europe, with Caribbean Netherlands, overseas territories in the Caribbean. It is the largest of the four constituent countries of the Kingdom of the Nether ...

. The actual conversion was led by a design team formed by Van Oord ACZ. Post-conversion, the ship remained a capable bulk carrier, albeit with a reduction of in cargo capacity and a loss of of sailing speed. Conversion was scheduled for a maximum of 112 days, and was completed in 124 days.

Design challenges

Its large size (largest in the world of its type at the time of construction) created design challenges. In order to create an economically feasible vessel of this size, the vessel must be designed with a high

deadweight tonnage Deadweight tonnage (also known as deadweight; abbreviated to DWT, D.W.T., d.w.t., or dwt) or tons deadweight (DWT) is a measure of how much weight a ship can carry. It is the sum of the weights of cargo, fuel, fresh water Fresh water or ...

and a relatively high sailing speed to allow large quantities of rock, with densities ranging from per cubic meter or per cubic yard, to be rapidly transported to deeper waters farther from shore. Because of the density of the rock, the ship must include large void spaces located ahead of, astern of, and to either side of the

cargo hold 120px, View of the hold of a container ship A ship's hold or cargo hold is a space for carrying cargo in a ship or airplane compartment. Description Cargo in holds may be either packaged in crates, bales, etc., or unpackaged (bulk cargo). Acc ...

s in the hull to provide sufficient stability. The holds themselves are loaded from above through hatches by shore-based equipment. They are designed with sloping sides and bottoms to allow them to be self- trimming and self-unloading via a

conveyor belt A conveyor belt is the carrying medium of a belt conveyor system (often shortened to a belt conveyor). A belt conveyor system consists of two or more pulleys (sometimes referred to as drums), with a closed loop of carrying medium—the conveyor b ...

running the length of the holds along the centerline of the ship at their lowest point. The conveyors transport the rock to the forward part of the ship, into a rock hopper, then into flexible fall pipes that extend out of the ship's bottom through a

moon pool A moon pool is an equipment deployment and retrieval feature used by oil platforms, marine drilling platforms, drillships, diving support vessels, fishing vessels, oceanography, marine research and underwater exploration or research vessels, and ...

. The ends of the fall pipes are fitted with purpose-built, state of the art

remotely operated vehicle A remotely operated underwater vehicle (ROUV) or remotely operated vehicle (ROV) is a free-swimming submersible craft used to perform underwater observation, inspection and physical tasks such as valve operations, hydraulic functions and other g ...

s (ROVs) which ensure that the fall pipes are accurately guided along the cable or pipeline, ensuring highly precise deposition of protective rock ballast. These ROVs can also be used for

dredging Dredging is the excavation of material from a water environment. Possible reasons for dredging include improving existing water features; reshaping land and water features to alter drainage, navigability, and commercial use; constructing d ...

trench A trench is a type of digging, excavation or depression in the ground that is generally deeper than it is wide (as opposed to a swale (landform), swale or a bar ditch), and narrow compared with its length (as opposed to a simple hole or trapping ...

ing, and jetting tools. The large quantity of heavy equipment mounted above the main deck of the ship raises its

center of gravity In physics, the center of mass of a distribution of mass in space (sometimes referred to as the barycenter or balance point) is the unique point at any given time where the weighted relative position of the distributed mass sums to zero. For ...

and reduces its transverse stability.

Sinking

MV ''Rocknes'' hit shallow water and suddenly

capsize Capsizing or keeling over occurs when a boat or ship is rolled on its side or further by wave action, instability or wind force beyond the angle of positive static stability or it is Turtling (sailing), upside down in the water. The act of reco ...

d in four minutes south of

, Norway, while on her way to

Emden Emden () is an Independent city (Germany), independent town and seaport in Lower Saxony in the north-west of Germany and lies on the River Ems (river), Ems, close to the Germany–Netherlands border, Netherlands border. It is the main town in t ...

in Germany, killing 18 of 30 crew. She remained afloat upside-down.Smit International corporate website: Salvage project details o
Rocknes
, February 2004, visited 12 February 2012

Salvage

The Dutch salvaging company

Smit International Smit Internationale N.V. (or Smit International) is a Dutch company operating in the maritime sector. Founded in 1842 by Fop Smit, it provided towing services in the Port of Rotterdam. Within its first decades, it branched into shipbuild ...

was hired to salvage the ship. As she had remained afloat upside down, a plan was designed to parbuckle the vessel, an exceptional approach for a ship of this size. Cables were attached from the 9000-ton vessel to two barges that had been specially prepared for this operation. She was towed into the harbour of Bergen, still capsized and after repairs the bulk-carrier was put back in operation.

In the media

The sinking of ''Rocknes'' was broadcast on

Discovery Channel Discovery Channel, known as The Discovery Channel from 1985 to 1995, and often referred to as simply Discovery, is an American cable channel that is best known for its ongoing reality television shows and promotion of pseudoscience. It init ...

in an episode of ''

Blueprint for Disaster ''Blueprint for Disaster'' is a Canadian documentary television series that premiered in 2004 on Discovery Channel Canada. Produced by Temple Street Productions, the program investigates why and how various disasters have happened. Toronto-based ...

'' (in Europe broadcast under the name ''Minutes from Disaster''). The sinking of the ''Rocknes'' also features in season 1 of '' Disasters at Sea''.

References

{{DEFAULTSORT:Rocknes 2004 disasters in Europe Maritime incidents in 2004 Merchant ships of Antigua and Barbuda Merchant ships of the Netherlands Ships built in Hamburg 2001 ships Bulk carriers January 2004 in Europe