Combined energy management and calculus of variations approach for optimizing hypersonic vehicle trajectories

An efficient performance analysis method is developed to evaluate potential hydrogen fueled turbojet, ramjet and scramjet propulsion for advanced technology hypersonic aircraft. An algorithm, based on energy management and calculus of variations, is developed for determining optimal trajectories. The methodology applies both techniques simultaneously in obtaining the optimal trajectory. Many mission, flight, and vehicle-related requirements and constraints are satisfied in the process. In addition, powered hypersonic flight produces unique performance characteristics not encountered at subsonic speeds. With the analysis method, two potential hypersonic vehicles are evaluated, both for maximizing payload and minimizing time to climb, and the resulting optimal trajectories are presented.