Hybrid-Electric distributed propulsion (HEDP) is becoming widely accepted and new tools will be required for future development. This Phase I SBIR proposal creates a turbo-electric, hybrid electric propulsion system sizing and weight synthesis tool specifically designed for use in an MDAO framework. It will offer significant flexibility regarding placement of the propulsive devices for top-level hybrid design, including over-wing, under-wing, split-wing, fuselage pylon-mounted, and other configurations. The user will supply power required, fan speed, fan torque, TOGW estimation, desired power split between engines and batteries, and selection for propulsion system locations. Sizing and weight analysis for electric motors, generators, speed controllers, gearboxes, cables, transformers, batteries, and cooling systems will be considered including structural considerations for heavily modified aircraft components for each system. The outputs will be hybrid electric propulsion system weight, sizes for the sub-system components, and revised HEDP specific TOGW calculation. The overall goal of this proposal is to provide a tool within a framework for top-level and conceptual hybrid electric propulsion studies. Additionally, the fidelity of the current NASA models is based on empirical-data and extrapolations. This proposed tool will employ physic-based models with empirical corrections, when needed. A Phase II and future commercialization plan have been identified.