Waterjets represent the most successful and efficient means of propulsion for high-speed applications.



The advantages of waterjets are not only that they produce higher efficiency, but that they also result in lower vessel resistance due to the absence of underwater appendages, such as shafts, rudders and shaft struts. The absence of any parts below the waterline also makes waterjets an ideal solution for shallow water operation.
Wärtsilä offers a variety of waterjet propulsion solutions. The range is based upon both axial and non-axial pump designs.

The axial pump design is the optimum solution for vessel design speeds of up to 55 knots. It delivers the best power to weight ratio, and the smallest transom mounting flange dimensions available on the market.
Wärtsilä’s successful axial pump design is available in a pre-assembled unit for smaller jet units of up to approx. 4500 kW. It is designed to suit the needs of smaller boat builders. The inlet duct is included in the Wärtsilä kit and the unit is delivered on a skid with all auxiliary systems pre-mounted.
The larger jets beyond 4500 kW manufactured today, include 26,000 kW installed power per jet. Waterjets based on our axial pump design are installed in many key applications, such as the US forces’ Joint High Speed Vessel (JHSV) programme, and Littoral Combat Ship (LCS) programme.
The E-series waterjets are based on a non-axial pump design. This jet design serves applications that require extremely high power densities, notably for ship design speeds of up to 70 knots or more.