Kongsberg supplies rim-drive thrusters for India Research Vessel

Kongsberg Maritime has secured a contract to supply rim-drive thrusters for a new advanced acoustic research vessel for India’s Naval Physical and Oceanographic Laboratory (NPOL). Garden Reach Shipbuilders & Engineers (GRSE) is building the vessel for the Defence Research and Development Organisation (DRDO).

The vessel will support oceanographic and acoustic research missions. Kongsberg Maritime’s rim-drive thrusters were selected to meet extremely strict underwater noise limits, which are essential for acoustic research.

The rim-drive design removes the traditional gearbox. An electric motor is integrated directly into the propeller hub. This configuration delivers ultra-quiet operation, high efficiency, and precise manoeuvrability.

The propulsion package includes two RD-AZ2600 azimuth thrusters, two RD-TT1600 tunnel thrusters, and the MCON control system.

The contract marks an important milestone for Kongsberg Maritime. It brings the company beyond 100 rim-drive propulsion units delivered worldwide. Kongsberg Maritime launched the technology commercially ten years ago. Since then, it has become a benchmark for silent propulsion in research, naval, and specialised vessels.

Nils Reidar Valle, Senior Vice President, Naval & Workboats at Kongsberg Maritime, said the company is proud to support NPOL and GRSE. He highlighted that the rim-drive azimuth thruster delivers exceptionally low underwater noise for demanding research missions.

A GRSE spokesperson described the project as prestigious and said Kongsberg Maritime is a strong partner for vessels with strict technical requirements.

The azimuth thruster features a six-bladed propeller housed in a nozzle. This design improves low-speed thrust and reduces underwater noise. The motor integrates directly with the propeller and eliminates blade tips, which lowers cavitation. A permanent magnet motor built into the nozzle removes the need for additional cooling and simplifies installation and maintenance. The system uses no gears except for steering, reducing maintenance needs.

The research vessel will include advanced laboratories and equipment for oceanographic studies, sonar testing, and acoustic signature analysis. The rim-drive thrusters will enable quiet operations with minimal environmental impact.

Kongsberg Maritime will deliver the propulsion systems in line with the vessel’s construction schedule at GRSE.