Abstract :
WITH THE COMPLETION of its present construction program the United States Coast Guard will maintain a fleet of 13 turbine-electric a-c vessels having complete automatic control from the pilot house. They also are provided with either automatic or manual control from the engine room. Propulsion motors and generators are of minimum size because the use of regulated stability and automatic synchronizing permits the machines to be designed with very little inherent torque margin. Most of the vital propulsion auxiliaries are driven by motors taking power from a transformer connected to the propulsion bus and operate at from 90 to 15 cycles with facilities for transfer to a 60-cycle bus.