International Dredging Review

International Dredging Review

Global Ocean Technologies Limited (GOTECH) has performed a trial run of Kongsberg Simrad’s latest deep-water multibeam echo sounder the EM 120 and achieved highly accurate survey results. The trials were held in the Atlantic Ocean west of Ireland.

This system the first EM 120 to be delivered to the hydrographic market was installed onboard the GOTECH vessel S/V Bligh. Survey accuracy of 0.2 percent was achieved at 3000 to 4000 meters depth. Following the sea trial GOTECH reported that the general performance of the system exceeds Kongsberg Simrad’s EM 12. The S/V Bligh a well-established hydrographic and geophysical survey vessel also has a full onboard suite of Kongsberg Simrad post-processing software including seabed classification and mosaicing modules.

The EM 120 has a nominal sonar frequency of 12 kHz with an angular coverage sector of up to six times water depth and 191 beams per ping as narrow as 1„a. Full electronic compensation is provided for pitch roll and yaw stabilization. With a depth range of 20 to 11000 meters the EM 120 is designed for hydrographic mapping to full ocean depth.

Global Ocean Technologies Limited based in Dublin Ireland has also recently purchased a second EM 120 system and an EM 1002 to be installed on their survey vessel S/V Siren. In addition Kongsberg Simrad is scheduled to commission an additional three systems in the coming months for customers in Germany the United States and the United Kingdom.

The EM 120 is Kongsberg Simrad’s third generation of deep water multibeam echo sounders following the EM 12 in use in the commercial market and the EM 121A installed on the United States Navy’s T-AGS 60 class hydrographic survey vessels.