A model of an autonomous power system that generates and distributes power at 240 Hz has been developed. This high-frequency ac power system (HFAC) includes several gas turbine-generator units, two propulsion power trains, several power distribution and conversion units, a super-capacitor energy storage module, a high-power pulse load, and multiple service loads. Four case studies are considered. These are: partial loss of generation, application of a large step load, power restoration to a vital load, and operation of energy storage. Preliminary analysis shows that the power system remains under control during the four events. Some benefits of the HFAC architecture are highlighted first and analysis results of the case studies follow.