Optimal Trajectory Generation and Design Trades for Hypersonic Vehicles

A method for determining the optimum trajectory flight path for an air-breathing single-stage-to-orbit vehicle is presented. A calculus of variations direct method of steepest descent is employed to determine angle-of-attack, bank angle, and engine power setting time histories. Trajectory profiles resulting from using both nominal and off-nominal vehicle system parameters and environmental conditions are addressed. Design and/or control trades which will become apparent from trajectory study results are identified. Considerations affecting the application of analysis algorithm features to the on-board guidance strategy are also discussed.