Norway’s Ulstein Group has announced the introduction of the X-Stern, intended to increase operability through positive effects on station keeping, wave response, comfort and safety in harsh conditions.

An offshore vessel with the X-Stern has increased operability in harsh conditions

An offshore vessel with the X-Stern has increased operability in harsh conditions

The X-Stern is said to encompass several characteristics of the company’s X-Bow, which was introduced to maintain ship speed in poor weather while maintaining crew comfort and cutting fuel consumption. The X-Stern has been developed for North Sea conditions, allowing ships to stay on position in harsh weather with the stern towards waves, wind and current. For vessels where the best possible motion characteristics are vital, the X-Stern can be positioned towards the weather instead of the bow.

According to Ulstein, the X-Stern leads to reduced pitch and wave drift forces, as well as eliminating slamming. Positive effects are reduced power and fuel consumption while on DP, or the possibility of operating in a wider sector with the same power consumption. It is said to offer additional ice operation capabilities. Its gentle displacement reduces acceleration, pitch and heave, it improves comfort and safety, and the operational window is increased. Ulstein says there will be no sea on deck, and reduced ice build-up in cold climates, due to the stern shape and enclosed nature of the aft deck.

“We work strategically in order to come up with safer, smarter and greener solutions,” said Tore Ulstein, deputy CEO and head of markets and innovations. “We discuss operational challenges with our customers, and work on how to transfer these challenges into technical solutions which can be turned into commercial products. The X-Stern is patent-pending in several countries, including the USA and in the EU.”