Abstract

Driven by the recent development in advanced air mobility and the need to transition to more sustainable aviation, this thesis provides a framework for the optimal flight management strategy that minimizes the direct operating cost (DOC) of a hybrid-electric aircraft in steady cruise flight. Specifically, this thesis solves the minimum DOC problem for a hybrid-electric aircraft flying in a constant wind field. Polynomial equations whose positive real roots are the solutions of the minimum DOC problem are obtained using Pontryagin’s minimum principle. The optimal solutions are simulated using the shooting method. The results of the shooting method are also validated using MATLAB's built-in boundary-value problem solver. Furthermore, this thesis studies the specific case of hydrogen hybrid-electric aircraft based on data found in the literature and compares it to kerosene-fuel hybrid-electric aircraft. Additionally, the optimal energy management strategy of the hybrid-electric aircraft is investigated through the simulations of multiple scenarios for two different aircraft.