A hybrid electric aircraft simulation system and test bed is proposed to provide a dedicated development environment for the rigorous study and advancement of hybrid electric powered aircraft. The new test bed and simulation system will provide a dedicated platform and set of analysis tools to study, design, and test hybrid electric powered propulsion components and systems for use in commercial, general aviation, military, and UAV systems. The test bed will allow various hybrid electric propulsion system technologies to be tested to determine performance, reliability, safety, and cost. These include various motors, motor controllers,gas turbines, batteries, fuel cells, super capacitors, propeller, and fan technologies. Additionally, the platform could be used to investigate performance characteristics unique to hybrid electric propulsion, determine the most accurate methods for measuring energy used and remaining, and research redundancy possibilities unique to hybrid electric aircraft. Studies performed during Phase I demonstrated that pure electric aircraft are limited in range and endurance by the specific energy of current battery technology. Although there is a great deal of effort being put into advanced batteries, the most practical solution in the near term is to utilize a hybrid electric system. The proposed Phase II program builds upon the Phase I results by developing a detailed propulsion system simulator model for hybrid electric propulsion systems, with the ultimate goal of a bench test model of the propulsion system. Using a detailed multi-platform/mission trade study, a coupled parallel, uncoupled series, and split series-parallel hybrid system architecture will be compared to determine the most advantageous and efficient. The propulsion system simulator will also be used to perform a sensitivity analysis of each architecture to determine critical performance aspects for individual components.