Offshore industry leader Allseas has selected Dutch maritime design firm Vuyk Engineering to design its new semi-submersible Heavy Transport Vessel (HTV), named Grand Tour.
This vessel is purpose-built to facilitate seamless topsides transfers to Allseas’ flagship vessel, Pioneering Spirit, marking a significant advancement in integrated offshore transport and installation capabilities. Construction of the Grand Tour will take place at Guangzhou Shipyard International, with delivery expected in the first quarter of 2028.
Vuyk Engineering has optimized the vessel to carry payloads of up to 60,000 tonnes. What sets the Grand Tour apart is its ability to load and transport topsides weighing up to 40,000 tonnes at the stern, designed to fit precisely into the bow slot of Pioneering Spirit.
This configuration enables safe and efficient offshore handovers. The vessel’s semi-submersible hull, featuring a 57m beam, provides enhanced stability and allows access to shallow-draft fabrication yards around the world.
With a strong track record in designing semi-submersible transport vessels, Vuyk also brings expertise in integrating alternative fuel technologies aimed at reducing emissions. The Grand Tour reflects Vuyk’s commitment to delivering future-ready solutions tailored to the evolving needs of the offshore energy sector.
Floris Toetenel, Director at Vuyk Engineering, highlighted the long-standing relationship with Allseas and expressed pride in continuing that legacy through the concept and basic design of the new HTV. He noted that the vessel builds on Vuyk’s experience with Pioneering Spirit and embodies a shared commitment to innovation, efficiency, and sustainability.
Key design features of the Grand Tour include a 180 x 57m cargo deck capable of supporting direct skidding, /roll-off, and /float-off operations. The vessel will be equipped with a methanol-ready propulsion system, an air lubrication system, and podded propulsion to reduce fuel consumption. A high-capacity ballast system will ensure precise load transfers during operations.
The Grand Tour Heavy Transport Vessel (HTV) boasts impressive specifications that reflect its advanced engineering and purpose-built design for offshore transport and installation.
Measuring 229.9m in overall length, the vessel offers substantial capacity and stability for heavy-duty operations. Its moulded beam of 57m and moulded depth of 14.8m contribute to its robust structure, while a summer draught of 11.1m ensures it can access a wide range of global fabrication yards.
Equipped with a DP2 positioning system, the vessel is capable of maintaining precise station-keeping during complex offshore operations. Propulsion is provided by four thrusters rated at 3,500kW each, supported by a retractable thruster of 2,600kW and two tunnel thrusters of 2,000kW each, offering excellent maneuverability and control.
The Grand Tour has a deadweight capacity of 73,000 tonnes at an 11-metre draught, making it suitable for transporting extremely heavy topsides and modules. Its deck space spans 10,260 square metres, designed to accommodate various loading methods including skidding, /roll-off, and /float-off operations. Notably, the vessel can transport up to 40,000 tonnes at the stern, specifically engineered to align with the bow slot of Pioneering Spirit for seamless offshore handovers.
