Another UT design for Island Offshore

This latest delivery will act principally as an accommodation vessel connected to an offshore platform, but it is also equipped for subsea construction and ROV operation , and for transporting liquid and bulk supplies.

The 99.8m length version was specified for Island Crown, built at Vard Brevik, as well as a four-genset diesel electric propulsion system, Azipull main thrusters and twin tunnel thrusters with a swing up azimuth thruster at the bow. This arrangement provides the high level of redundancy required for DP2 class, while the increased length contributes to lower motion in the seaway.

The ship features accommodation for about 40 personnel. The hotel block is placed aft of the main superstructure, with a hospital and services at main deck level and two decks of twin cabins, day and meeting rooms above.

To transfer workers between the ship and platform, a transfer gangway is positioned at the port aft corner of the deck. Island Crown can link to different types of platform, ofa variety of heights above water level. The access system comprises a telescopic tower and staircase which takes care of the initial height differences; and the gangway itself, linking the top of the tower and the docking point. The gangway is hydraulically positioned but free to pivot, allowing for relative motion. Normally, the vessel will maintain a fixed distance from the platform under DP, at a heading that as far as possible minimises the energy required by the thrusters to keep station.

Island Crown is designed according to SPS (special purpose ship) rules which set limits on stability and angle of heel under various scenarios. Two enclosed lifeboats and two MOB boats can cater for up to 100 people. For service and construction roles, Island Crown is equipped with a long boom crane on the starboard side with capacity between 10t at 40m to 100t at 10m.