Kongsberg Maritime Wins Contract to Power India’s Next-Generation Acoustic Research Vessel

New Delhi : Kongsberg Maritime has secured a significant contract to supply its advanced rim-drive propulsion systems for a new acoustic research vessel being built for India’s Naval Physical and Oceanographic Laboratory (NPOL), marking a major step forward in India’s underwater research and naval science capabilities.

According to a company press release, the vessel is currently under construction at Garden Reach Shipbuilders & Engineers (GRSE) in Kolkata and is being developed to support specialised oceanographic and acoustic research missions for India’s Defence Research and Development Organisation (DRDO). Once delivered, the ship will form a critical part of India’s long-term strategy to enhance indigenous underwater sensing, sonar evaluation, and acoustic signature analysis.

Ultra-Quiet Propulsion for Sensitive Acoustic Missions

The contract centres on the supply of Kongsberg Maritime’s rim-drive thrusters, a propulsion technology specifically chosen to meet exceptionally stringent underwater radiated noise requirements. For acoustic research vessels, propulsion noise can directly interfere with sonar measurements and underwater data collection, making ultra-silent operation a decisive factor in system selection.

Unlike conventional propulsion systems, the rim-drive design eliminates the traditional gearbox and places an electric motor directly into the propeller hub. This architecture dramatically reduces vibration, mechanical noise, and cavitation, while also improving efficiency and manoeuvrability. The result is a propulsion solution ideally suited for low-speed, high-precision scientific operations in acoustically sensitive environments.

Comprehensive Thruster and Control Package

Under the contract, Kongsberg Maritime will deliver a complete propulsion and control package comprising two RD-AZ2600 rim-drive azimuth thrusters, two RD-TT1600 rim-drive tunnel thrusters, and the company’s MCON integrated control system. Together, these systems will provide the vessel with high redundancy, precise dynamic positioning capability, and smooth, low-noise handling across a wide range of operating conditions.

The azimuth thrusters feature a six-bladed propeller housed within a nozzle, optimised to enhance low-speed thrust while minimising underwater noise. The absence of blade tips reduces cavitation, a key source of acoustic disturbance. A permanent-magnet motor built into the nozzle removes the need for separate cooling systems, simplifying installation and reducing maintenance demands. With no mechanical gears apart from the steering gear, the overall design offers high reliability and low lifecycle costs.

Crossing the 100-Unit Global Milestone

This project also represents an important commercial and technological milestone for Kongsberg Maritime, taking the company beyond 100 rim-drive propulsion units delivered worldwide. The rim-drive technology was first introduced commercially a decade ago and has since become a benchmark solution for research vessels, naval platforms, and specialised commercial ships requiring silent and efficient propulsion.

Nils Reidar Valle, Senior Vice President, Naval & Workboats at Kongsberg Maritime, said the contract highlights both the maturity of the technology and its relevance for advanced defence research. He noted that the rim-drive azimuth thruster is the quietest in its class, capable of meeting the most demanding acoustic research standards, and described the 100-unit milestone as clear evidence of the company’s sustained commitment to innovation.

GRSE and International Collaboration

A spokesperson for GRSE described the vessel as a prestigious national project, underlining the shipyard’s confidence in Kongsberg Maritime as a technology partner capable of meeting the strictest operational and acoustic requirements. The collaboration reflects GRSE’s growing role in delivering complex, high-technology vessels for both the Indian Navy and defence research establishments.

Strengthening India’s Strategic Research Capability

The advanced acoustic research vessel will be equipped with state-of-the-art laboratories, sensor suites, and data acquisition systems to support oceanographic surveys, sonar trials, and detailed acoustic signature studies. Such capabilities are vital for improving underwater situational awareness, validating indigenous sonar systems, and supporting future naval platform development.

With the integration of Kongsberg Maritime’s rim-drive thrusters, the vessel is expected to combine operational flexibility, extreme acoustic discretion, and minimal environmental impact, aligning closely with India’s strategic and scientific objectives in the maritime domain.

Delivery of the propulsion systems will be synchronised with the vessel’s construction schedule at GRSE, ensuring seamless integration as the project progresses toward completion.