Largest turbine installation vessel

The largest turbine installation vessels are the sister ships Pacific Osprey and Pacific Orca, both of which have a gross tonnage of 24,586. The ships are operated by Swire Blue Ocean (DNK), and were built in 2012 by Samsung Heavy Industries in South Korea.

Turbine installation vessels are unusual ships designed for the construction and maintenance of offshore wind farms. They have a shallow draft, a low, flat deck, and – most notably – the ability to raise themselves up out of the water on huge extendable legs. This last feature (which gives these vessels their alternative name, "jack-up ships") transforms them from a ship into a stable platform for an onboard construction crane. These legs typically extend around 40 m (131 ft), which is more than long enough to reach the seafloor in the shallow seas where wind turbines are deployed, such as the North Sea.

These ships use technology originally developed for offshore oil and gas exploration. The first purpose-built Turbine Installation Vessel was the MPI Mayflower (later Resolution), built in 2004.