Electrically powered small unmanned aerial systems face limited range and endurance due to the inherently low energy density of current level of technology batteries. Hybrid gas-electric systems are under development and show promising signs of increased range and endurance, however piston based hybrid systems must overcome several challenges to be effective. Turboelectric power systems leverage the high energy density of hydrocarbon fuels in conjunction with the high power density of electric propulsion systems while mitigating some of the typical issues encountered with piston-based hybrid systems. In this study, a 7.3kW turboelectric power system for a small unmanned aircraft is realized through several phases of design, including an airframe integration phase. Though previous literature suggests a range of anticipated electrical efficiencies, the driving factoring contributing to power system losses are not well discussed. Thus, there exists a critical need to develop and validate a design approach that assesses compatibility of components of the electrical system and how component selection affects efficiency. Several overall system models were developed and evaluated for a general turboelectric power system over a range of operating conditions. System level design implications is discussed in detail, enabling optimization of the components during the design phase. An active throttle controller was designed, realized, and evaluated for the system described. The function of the throttle controller ranges from starting and stopping of the turbine to regulation of turbine throttle via feedback control. Switching between power sources and the difficulties associated with this will also be discussed in detail. The turboelectric system was installed on a Mugin 4500 fixed-wing unmanned aerial system and evaluated in terms of thermal management and operability. Results of this study will demonstrate feasibility of turboelectric power systems as an alternative to traditional all-electric propulsion systems and serve as a stepping-stone for future studies on small-scale turboelectric propulsion and power.