Allseas has started construction of its new semi-submersible heavy transport vessel Grand Tour at Guangzhou Shipyard International (GSI) in China.

Construction began on 16 September, with delivery scheduled for Q1 2028. Grand Tour will have a carrying capacity of up to 60,000 tonnes.

The vessel will measure 230 m in length and 57 m in width. It is designed to transport large offshore structures, including next-generation 2 GW offshore wind converter platforms.

Grand Tour is also designed to fit inside the bow slot of Pioneering Spirit, allowing structures transported by the vessel to be transferred directly for installation.

According to Allseas, the arrangement combines the transport and installation stages and is intended to support the movement of offshore structures from fabrication yards to installation sites.

The addition of Grand Tour is expected to expand Allseas’ heavy transport capabilities when the vessel enters service in 2028.