The tool, which is able to cut lines at depths of up to 4,000 metres (13,123 feet) – twice the maximum operational range of existing subsea communication ... s second island chain, a defence ...

The RT-1 'Rock Trencher' will set a new standard in subsea trenching. CTC Marine Projects, a subsidiary of DeepOcean ASA, is building the world's largest and most powerful rock trenching vehicle.