A nearly 300-meter passenger vessel operating in a high-traffic cruise terminal required the installation of a new bow thruster to support maneuverability and safe port operations. Due to the vessel’s size, operational schedule, and the need to avoid drydocking, the work had to be performed underwater while the ship remained afloat. Subsea Global Solutions was engaged to execute the installation using commercial diving techniques, ensuring minimal disruption to the vessel’s operational timeline.

The Challenge

The installation of a new bow thruster on a vessel of this size presented several technical and operational challenges. All work had to be conducted within the confines of the thruster tunnel, requiring precise underwater alignment, welding, and rigging in limited visibility conditions. The project involved multiple phases spread across several operational windows, demanding consistent coordination with shipboard engineering staff and strict isolation procedures to ensure diver safety. Additionally, the installation required certified welding, nondestructive testing, and protective coatings to meet class and operational requirements, all while maintaining schedule certainty within an active cruise port environment.

Scope of Work & Solution

Subsea Global Solutions executed a phased underwater installation of the bow thruster system over multiple shifts. The scope included Installation of an internal cofferdam, thruster unit, and stay plate/strut, as well as a bolts & keeper bar, and filling of the unit with oil. Epoxy coatings were applied to protect newly welded components, followed by magnetic particle inspection (MPI) to verify weld integrity. Divers also removed blade chalks and pad eyes to prepare the thruster for commissioning, installed port and starboard tunnel gratings, and completed anode installation where structural conditions allowed. Throughout the project, Subsea Global Solutions maintained daily coordination meetings with vessel personnel, completed full photo documentation, and ensured all work was performed in accordance with safety, quality, and class requirements.

Conclusion

The underwater bow thruster installation was completed successfully, restoring the vessel’s maneuvering capability without the need for drydock. Subsea Global Solutions delivered the project safely, efficiently, and in alignment with the vessel’s operational schedule, demonstrating the value of experienced commercial diving teams for complex underwater installations on large passenger vessels. The completed work supported the vessel’s return to service with minimal operational impact.

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Underwater Tunnel Thruster Exchange & Repair Services

Subsea Global Solutions delivers expert underwater tunnel thruster exchange and repair services designed to reduce vessel downtime and eliminate the need for drydocking. Our experienced diver-technicians are equipped to perform complete thruster removals, installations, inspections, and repairs underwater using proven, class-approved methodologies. From damage assessment and component replacement to alignment, sealing, and functional verification, our teams ensure thruster systems are restored to safe, efficient operation. Available worldwide and on short notice, Subsea Global Solutions provides shipowners and operators with a reliable, cost-effective solution to maintain maneuverability and operational readiness.