Guangzhou Shipyard International (GSI) has begun sea trials of a 71,000-tonne semi-submersible heavy transport vessel under construction for COSCO Shipping Specialized Carriers in China.
The vessel departed the shipyard on 8 October 2026 and headed to a designated offshore testing area for a programme expected to last approximately two weeks.
Developed jointly by GSI and Shanghai Merchant Ship Design & Research Institute (SDARI), the vessel measures 243.10 m in length, 49.00 m in beam and 14.5 m in depth. It features a 9,850 m² cargo deck, a maximum submergence depth of 27.5 m and a DP-2 dynamic positioning system.
The design is intended for transporting large and heavy cargo across international waters, with the semi-submersible configuration allowing the vessel to submerge and refloat during cargo operations.
Before departure, the vessel completed its mooring trials, with key equipment including the main engines, auxiliary engines, steering gear, anchoring equipment, ballast system and dynamic positioning system successfully commissioned on the first attempt.
During construction, the project team established dedicated groups for ballast tank closure and electrical automation work. The programme included closure work across 103 ballast tanks and integrated testing of the vessel’s control and automation systems.
The vessel also received a score of 93.2 in its readiness assessment before proceeding to sea trials.
The current trials will cover main engine operation, speed measurements, steering and anchoring tests. The programme will also include full-cycle testing of the vessel’s submergence and refloating operations to verify its core semi-submersible capabilities.
Following completion of the sea trials, the vessel will move towards the remaining stages of testing and delivery preparations.
