Using a world first installation system, Clough Stena (Asia) Joint Venture (CSAJV) is well underway to completing the Amoco Orient Petroleum Company`s (AOPC) floating production facilities in the South China Sea Liuhua 11-1 field. In order to overcome the installation difficulties created by 320 metre water depth, massive volume and weight of materials and 700 tonne tensioning loads, CSAJV developed the world`s first vertical lay and tension system (VL and T) and undertook a major vessel conversion. The diving support vessel Essar Stena 1 was converted for the Liuhua 11-1 installation project to provide a deepwater mooring installation vessel. It was subsequently renamed the CSO Venturer. The vessel, together with the new VL and T system are said to have proved themselves capable of successfully laying and tensioning mooring components in the deep waters of the South China Sea. fig., photos.