The DN120 lays cables in shallow water. The Sunfish and Moonfish burry them at the pre-set depth.

The Sunfish and the Moonfish were indispensable for the Race Bank project. But, obviously, they were not alone.

“Export cables may look very solid, but applying too much force while pulling them is absolutely advised against. To be able to pull the cable ashore from the cable-laying vessel, we wanted to position it very close to the coast. With its laden draught of 6.5 metre, the Isaac Newton was no option as it would get no closer than about eight kilometres off the coast. That’s why we decided to use the DN120, originally a rock installation pontoon but built according to Jan De Nul’s philosophy and thus relatively easy to convert into a cable-laying platform on the one hand and a transport and control platform for the Sunfish and Moonfish, which would subsequently dig in the cables, on the other. We succeeded in bringing the DN120 up to two km off the coastline, just outside the vegetation area. As such, the DN120, the Sunfish and the Moonfish bridged the distance from the coast to where the Isaac Newton could take over, about eight kilometres off the coast.

Patrik Lowie: “We cleared the entire deck of the DN120 and installed the necessary equipment. A large carousel for winding and unwinding the cable, an automated anchoring system to enable the DN120 to move in a straight line, a system for the remote control of the Moonfish because also the operators controlling the Moonfish through a so-called ‘control umbilical’ operated from the DN120. Bear in mind that the Moonfish is an amphibious but semi-submersible vehicle working half the time below water. On the Sunfish, operators could stay on board, on the Moonfish this was never an option."

Related articles

Divisions work together to win projects

"In fact, we are able to win such projects at the time everything is still on the drawing board,” explains Patrik Lowie. “The trick is to simulate and visualise all possible situations beforehand. Looking at this from a distance, one…

Read more
Isaac Newton: with 63 km of cable in one go the world's largest cable-laying vessel

“We are a work in progress, getting better by the day,” says Rutger Standaert. On his business card, he carries the title of ‘Technical Superintendent New Building Design’ or, in short, one of the naval architects at Jan De Nul.…

Read more
Nature reserve The Wash

Special rules apply in the vast bay where the electricity generated by the offshore wind farm Race Bank comes ashore via two heavy export cables. The Wash really is a unique nature reserve, a series of vast salt marshes that, under the influence of strong…

Read more
A particularly voluminous report helped to convince the customer

In our Marine Environmental Department, in short Mared, about twenty people are investigating all kinds of environmental aspects. Ine Moulaert explains: “Nowadays, whenever any of our business units wants to win a project, we almost always conduct…

Read more
Testing 10 biological oils

In connection with the Race Bank project, Alain Pieters from the R&D department was asked whether the seals of the trencher Moonfish would not be affected by the use of biodegradable oil. “The client wanted to avoid that, in the event of a…

Read more
Flexibility is the operative word in the drawing office

The ship building department drawing office is an indispensable part of Jan De Nul’s engineering services. One of its main activities is designing equipment for our vessels. As among Jan De Nul’s shipbuilders, flexibility is the operative…

Read more
Integration is the way forward

Wouter Vermeersch is responsible for Jan De Nul’s offshore cable division. He confirms that business is going well and that the future looks promising: “Thanks to the increasing integration between the various business units of Jan De Nul,…

Read more
Homemade machines

Dries Lammens was among Jan De Nul’s engineers who were present when the requirements set to the Sunfish and Moonfish were put on the table. “A project for which so far no equipment existed but for which it must be created is no doubt a challenge,”…

Read more