There is an effort at the moment to include helicopter drones in the arsenal of national navies. The rotor-blade design allows for more classes of ships .
The Power Systems division of Rolls-Royce has been selected to supply a further four of its mtu naval generator sets for the USS Congress (FFG-63), the second ship in the U.S. Navy’s Constellation Class Guided-Missile Frigate program, previously known as the FFG(X) program.