The U.S. Navy has built a 133 foot long scale model of a future warship, the Sea Jet, to test performance of main electric drives, and to test the use of an all water jet propulsion system. The water jet system, called AWJ-21, was designed by Rolls Royce Naval Marine. Water jet systems have been used as auxiliary propulsion systems for decades. But the U.S. Navy wants to replace the conventional rudders and (screw) propeller completely with a water jet system.
The tests will be conducted in an Idaho Lake. After the AWJ-21 tests are completed, the Sea Jet will have the water jet system removed, and another new propulsion system, RIMJET, installed and tested. RIMJET is a conventional propeller mounted in a pod installed outside the ship. Each pod contains an electric motor, the drive mechanism, and the propeller. The purpose of both these tests is to find out if the new systems will make the ships quieter and more nimble, especially in coastal waters. The navy wants to begin building all electric ships within the next decade. This is especially urgent with the recent development of more efficient laser cannon, which needs large amounts of electricity for their “ammunition.”