VESSEL REVIEW | Altera – Large cable layer with shallow-water capability

N-Sea said it designed and procured the deck spread using lessons learned from previous offshore wind and interconnector cable installation and repair projects.

Subsea Cable Assets provided Altera with a turnkey cable lay spread. Its scope included the carousel, the loading tower, the tensioning equipment, cable routing hardware, and related control systems.

MacArtney meanwhile supplied a vertical tensioner rated at three tonnes for the loading tower, a 15-tonne main-deck tensioner with breakback functionality, quadrant handling, the carousel drive system, and cable lay controls. There are cable spread options for 3.3-metre and five-metre minimum bend radii, together with infield and export modes.

The offshore knuckle boom crane is positioned aft on the starboard side and is rated at 25 tonnes at a reach of 25 metres, or 15 tonnes at 37 metres. A separate auxiliary crane forward on the port side is arranged to reach the carousel.