Spread mooring system consists of a group of mooring lines attached to the bow or stern of the vessel and anchors on the seabed. The connection is relatively simple because the vessel is positioned in a fixed heading and does not allow the vessel to “weathervane”, which means to rotate in the horizontal plane due to wind, waves or current. The lack of weathervane capabilities means an increase of environmental loads, and therefore an increasing in number of mooring lines.
The spread moored system typically has a larger number of legs with increased component size than an equivalent turret moored. The spread moored system is easily expandable as it is more flexible to riser addition during the life of a field.