Asso's Trenching Fleet to depend on Sonardyne for Underwater Guidance

Submarine cable installation and repair specialist Asso Group has chosen underwater vehicle guidance technology from Sonardyne for its expanding trenching fleet.

The company, based in Greece and with operations globally, will install Sonardyne’s subsea Lodestar attitude and heading reference sensors (AHRS) on its trenching machines working across interconnector and offshore wind cable installation, protection and repair.

Asso Subsea specializes in hard soil conditions using its in-house designed fleet of shallow to deepwater trenchers. Its largest system, the nearly 13 m-long AssoTrencher IV, can cut trenches up to 2.3 m deep for burying power and telecommunications cables, including interconnectors and offshore wind inter array and export cables, in down to 800 m water depth.

Using Lodestar’s on its trenchers will allow technicians to complete cable laying and burial operations efficiently, by maintaining a high level of situational awareness of the platform’s dynamics, which is key when to keeping the vehicles on course in geotechnically challenging, zero visibility environments.

In addition to AHRS, some wind farm project specifications can also require the use of an inertial navigation system (INS) on trenchers, in order to ascertain an accurate as laid position of their subsea cables.

Last year, Asso won a contract to install the 66 kV export and inter-array cables on Vattenfall’s 350 MW Vesterhav Nord and Syd projects. The company was also awarded a contract, in consortium with Prysmian Group, to install the export cable system for the Gruissan floating offshore windfarm in southern France.