Rolls-Royce system on US Navy Sea Jet

The US Navy?s Office of Naval Research unveiled its new advanced electric-ship demonstrator ship, ?Sea Jet?, for the first time. The ship will test Rolls-Royce patented AWJ-21 water jet technology over the next six months on Lake Pend Oreille at the Navy?s Acoustic Research Department in Bayview, Idaho.

The AWJ-21 is designed to increase ship speed, making hulls sleeker by working without rudders, shafts and propeller struts. Unlike conventional water jets, the system works completely underwater, reducing noise and surface wake and improving stealth.

The lightweight and compact AWJ-21 allows ships to operate in shallow waters. Its integrated steering and reversing system improves manoeuvrability at low speeds.

Pat Marolda, Rolls-Royce President ? Naval, said: “This is a significant milestone in our development of an advanced water jet technology which offers new parameters in performance, bringing real benefits to the US Navy.”

The 133ft-long ship, known as an Advanced Electric Ship Demonstrator, is based on an advanced destroyer hull form and was built by Dakota Creek Industries, Anacortes, Washington in modules which were then assembled at Idaho.

Rolls-Royce also took the role of prime contractor for ship construction and system integration of the diesel/battery electric drive propulsion system.

Following demonstration of the AWJ-21, the RIMJET propulsor from General Dynamics Electric Boat will be installed in ?Sea Jet? for evaluation. The RIMJET is a novel type of podded propulsion system that relies on a permanent magnet motor to drive the propeller.